Aluminiumcontaining antacids are

Commonly prescribed but should be used with care, particularly in renal failure, because they are very constipating and because of the possibility of aluminium absorption. Aluminium is also contained within multiple negatively charged sulfated groups in sucralfate, which is a basic aluminium salt of sulfated sucrose. Although aluminium can be released from sucralfate with the production of detectable levels in serum, clinical harm from this phenomenon is unlikely, except perhaps in patients...

Endocarditis

Endocarditis refers to infective lesions on the heart valves or endocardium. As the organisms involved are usually bacteria, the term bacterial endocarditis is commonly used, though the organisms can sometimes be fungal, rickettsial or chlamydial. The term infective endocarditis (IE) is thus often used. Non-infective endocarditis may also be seen in non-bacterial, thrombotic, verrucous or Loeffler's endocarditis. Acute endocarditis of duration up to six weeks is usually caused by an aggressive...

Bibliography

Arsenian MA 1993 Magnesium and cardiovascular disease. Progr Cardiovasc Dis 35 271. Casscells W 1994 Magnesium and myocardial infarction. Lancet 343 807. Cholst IN, Steinberg SF, Tropper PJ et al 1984 The influence of hypermagnesemia on serum calcium and parathyroid hormone levels in human subjects. N Engl J Med 310 1221. ISIS-4 (Fourth International Study of Infarct Survival) Collaborative Group 1995 ISIS-4 A randomised factorial trial assessing early oral captopril, oral mononitrate, and...

Acyclovir

Acyclovir is the most important of the available antiviral drugs. It has replaced vidarabine (ara-A), the first available antiviral agent for systemic use in serious infections. It is a synthetic purine nucleoside analogue, structurally related to guanosine. Its unique mechanism of action inhibits DNA synthesis and thus viral replication. It therefore does not affect the latent virus. There is a low incidence of development of resistance, but unwarranted use is unwise. The antiviral effects of...

Shock

Anaphylaxis may occur in patients who have been similarly envenomated previously (e.g. snake handlers). Investigations include full blood examination (especially for haematocrit and platelet count), coagulation screen, electrolytes, renal function, and urinalysis. These should be carried out initially and then 8 hourly until any major acute changes have resolved. Treatment principles are outlined above. Spider bites mostly are harmless, though there are some major exceptions. The Sydney...

Inherited thrombophilia includes

activated protein C resistance (Factor V deficiencies (or abnormalities) of prothrombin (the recently described mutation, G20210A variant, with G A nucleotide substitution) low factor XII (46 C T mutation) has recently been considered paradoxically to be a possible thrombophilic rather than a haemostatic risk (after all, Mr Hageman whose name was originally give to factor XII died of pulmonary embolism) probably due to a mutant variant (called C677T) of the enzyme, 5,...

Late pericarditis may be produced

Radiation pneumonitis is an acute, primary, vascular reaction, initially with pulmonary vascular congestion and alveolar oedema, and later with small vessel thrombosis and alveolar epithelial desquamation. It is of variable extent and severity, but it occurs to some degree in all patients having chest irradiation. It may resemble P. carinii pneumonia, from which it therefore needs to be distinguished. Symptoms appear some weeks after radiation and include dry cough and dyspnoea. The overlying...

Syringomyelia see also Neural tube

Syringomyelia refers to local dilatation of the central canal within the cervical and or thoracic spinal cord. It is usually associated with the Arnold Chiari malformation (q.v.), but it can follow local injury or be associated with a spinal glioma. Clinically it causes a myelopathy, with both motor and sensory deficits in one or both arms. The sensory deficit involves especially pain and temperature. There may be neck pain, extending up to the occiput. Occasionally, there is an ipsilateral...

Viral and rarely bacterial infection

occasionally Gram-positive bacteria. The most important clinical consequence of rhabdomyolysis is acute renal failure from tubular obstruction due to pigment casts. There may also be tubular cell damage and afferent-efferent arterial imbalance, as well as hypovolaemia. Rhabdomyolysis is thus similar to haemolysis, with myoglobinuria causing problems similar to those from haemoglobinuria, but with some clearly distinguishing features, as indicated in the table below. pigment casts in the urine...

Erythema nodosuma

Erythema nodosum is possibly a delayed hypersensitivity reaction to inflammatory or pharmacological stimuli. Inflammatory triggers include streptococcal infection, especially of the upper respiratory tract, TB, sarcoidosis and inflammatory bowel disease. Pharmacological triggers include particularly sulfonamides and oral contraceptives. The condition usually occurs in young women. It appears as red, tender nodules, especially on the legs. It is associated with systemic symptoms of fever,...

Normalappearing bone marrow may be

Associated with defective red cell production and thus anaemia in systemic disease and in renal disease. Systemic diseases, such as inflammation, neoplasia and trauma, cause anaemia of chronic disease. This is normochromic and normocytic, with both the serum iron and iron binding capacity low and ferritin normal. The serum erythropoietin level is often low. The anaemia is generally mild and may be multifactorial, with IL-1 causing the trapping in macrophages of the iron from senescent red blood...

Goodpastures syndrome

Goodpasture's syndrome comprises pulmonary haemorrhage and glomerulonephritis, associated with autoantibodies to basement membranes of alveoli and glomeruli. Since the renal component can sometimes occur alone, an additional pulmonary injury may be required for full expression of the symptom-complex, such as viral infection or toxic exposure (including smoking). Clinical features are usually seen in young men, and the initial presentation is usually haemoptysis. The interstitial and alveolar...

Varicella

The varicella-zoster virus (VZV) is a member of the human herpesvirus group. It undergoes latency and reactivation as do other herpesviruses. Varicella is a highly communicable illness, with an incubation period of 11 20 days following droplet or direct contact. The virus is carried by the white blood cells to the skin and A vesiculating rash appears in successive crops, especially on the face and trunk. This resolves over 7 10 days. There is associated fever, headache and malaise. In adults, a...

Cholera

Cholera is an acute diarrhoeal disease caused by the Gram-negative bacillus, Vibrio cholerae. The usual pathogen was the 01 strain, mostly confined until 1961 to Asia. Subsequently, the 7th world pandemic was caused by the El Tor biotype. More recently, the 8th world pandemic which started in Southern and Eastern India in 1992 was caused by a new serogroup, 0139-Bengal. As humans are the only natural host, infection arises from faecal contamination of water or food. The organisms multiply in...

Other mediastinal diseases include chiefly

The most common, in neurogenic tumours (especially neurofibroma) cysts (especially bronchogenic or pericardial) thymoma (more often benign than malignant) teratoma (also more often benign than malignant) However, many different types of lesions may occur in the mediastinum, and their nature depends greatly on their site.

Scombroid

Scombroid poisoning is the commonest seafood poisoning worldwide. Enteric marine flora can degrade histidine, present in high concentration in the dark meat of many fish, to form histamine, the likely toxin in this condition. This process arises when caught fish are not cooled, and it can occur within even a few hours at room temperature. Once formed, the toxin is not destroyed by subsequent freezing or by smoking. The victim may note that the fish tasted metallic or peppery. The onset of...

Waldenstroms macroglobulinaemia is a

Heavy chain disease, with gamma, alpha or mu fragments, tends to behave as a chronic haematological malignancy. 4. Benign monoclonal gammopathy (so-called) may be seen in older patients. Eventually, classical myeloma develops in about 20 of patients within about 10 years if the gammopathy is IgG, and other lymphoproliferative disorders develop in about 50 of patients if the gammopathy is IgM. 5. Cryoglobulinaemia occurs when the abnormal plasma proteins are precipitated by cold. There are three...

Sleep disorders of breathing see

periodic and other abnormalities of breathing pattern primary alveolar hypoventilation the sleep apnoea syndromes. The first two groups of disorders are also more marked during sleep and are thus considered here. 1. Periodic breathing is best known in the form of Cheyne Stokes respiration, in which cycles occur of gradually increasing tidal volume followed by decreasing tidal volume and then transient apnoea, when the cycle is repeated. It is best explained by a lag in the normal control loop...

Drug allergy

Drug allergy is uncommon and comprises only 6 of all adverse drug reactions, which overall are, of course, common. Importantly, drug allergy can occur with only small doses of drug. However, most drug reactions of a seemingly allergic nature are not in fact immune-mediated (i.e. true allergy) but due to other effects often of a chemical nature, e.g. mast cell release. drug intolerance (an adverse pharmacological effect of a drug even at low dose), drug idiosyncrasy (a non-pharmacological effect...

Diabetic neuropathy

A neuropathy may be found in about 60 of patients with either insulin-dependent or non-insulin-dependent diabetes mellitus. The precise mechanism of production of this neuropathy is unclear. Polyneuropathy is seen in about half of these cases. There is symmetrical distal mainly sensory involvement. It is often subclinical, but mild symptoms are sometimes seen. These are especially paraesthesiae of the lower limbs, occasionally with sensory loss and even weakness and decreased reflexes. The...

Tetralogy of Fallot

Tetralogy of Fallot is the commonest cyanotic congenital heart disease. It comprises pulmonary stenosis (more commonly infundibular than valvular) an over-riding dextroposed aorta right ventricular hypertrophy. There is thus a right-to-left shunt, the degree of which varies with the degree of pulmonary stenosis. The shunt causes hypoxaemia, cyanosis and secondary polycythaemia. Coagulopathy due to reduced vitamin K-dependent clotting factors and platelet dysfunction give rise to a bleeding...

Vitamin K deficiency

Vitamin K deficiency was until recently thought to cause solely decreased plasma levels of four coagulation factors or clotting proteins, namely prothrombin (factor II) and factors VII, IX and X. This coagulation abnormality is most readily demonstrated by an increased prothrombin time. Although vitamin K was discovered in 1929 (and later named K for 'koagulation'), it was not until 1974 that its unique mechanism of action was elucidated and this in turn has led to the recognition of other...

Adrenocorticotropic hormone see

Also Adrenal insufficiency, Cushing's syndrome and Ectopic hormone production) Adrenocorticotropic hormone (corticotropin, ACTH) is the main controlling factor for the adrenal production of cortisol and androgens. It is produced in the anterior pituitary by cleavage of a large and complex polypeptide (241 amino acids), called propiomelanocortin (POMC), which also includes melanocyte-stimulating hormone (MSH), beta-endorphin, met-enkephalin, beta-lipotropin, and a number of other peptides of...

Purpura see also Thrombocytopenia

Idiopathic thrombocytopenic purpura (ITP) is due to an autoimmune IgG antibody, usually directed against the platelet membrane glycoprotein, GP Ilb IIIa. Sometimes there may be circulating immune complexes, as in HIV infection. Platelets with bound antibody are vulnerable to trapping and thus destruction via phagocytosis, especially in the spleen. Platelet production in the bone marrow increases by 3 4-fold, but this is only about half the known marrow reserve, perhaps because platelet...

Conns syndrome

Conn's syndrome comprises hypertension and hypokalaemia due to excess adrenal production of aldosterone. It is caused by benign unilateral adrenal adenoma (most commonly) bilateral adrenal hyperplasia, which is probably pituitary in origin (less commonly) adrenal carcinoma (rarely) genetic variant (rarely). This is inherited as an autosomal dominant, in which an abnormal gene product presumably has combined synthetic enzyme activities, so that excess aldosterone is dependent on ACTH and not on...

Euthyroid sick syndrome

The assessment of thyroid function is difficult in the seriously ill patient. This is because a variety of abnormalities of thyroid function tests may be found which seemingly reflect hypothyroidism, even in the absence of intrinsic thyroid disease. This state has thus been referred to as the euthyroid sick syndrome, and it may reflect the neuroendocrine effects of cytokines. It can occur very early in the course of serious illness, especially sepsis. Many aspects of serious illness affect...

Is not effective in the chronic fatigue syndrome

Acyclovir is not protein-bound but is distributed evenly throughout the total body water, except in the CSF in which the level is 25 50 of that in plasma. The urinary concentration is about 10 times the plasma concentration. It has a half-life of about 3 h, which rises six-fold in severe renal failure, since it is primarily excreted in the urine. It is 60 removed by dialysis. It is probably not mutagenic nor carcinogenic. Although fetal risk has not been shown, it crosses the placenta and...

Hypothyroidism

Hypothyroidism refers to the bodily deficiency of thyroid hormone. Myxoedema refers to the florid clinical syndrome associated with this. In fact, however, most patients with hypothyroidism have only mild symptoms, and indeed many are asymptomatic. Hypothyroidism has many causes, though more than 95 are due to intrinsic thyroid disease, from inflammation, especially Hashimoto's thyroiditis iodine deficiency or excess drugs, e.g. lithium, amiodarone, other iodine-containing medications A few...

Dengue

Dengue is produced by a group B arborvirus, indistinguishable in appearance from the Yellow Fever virus. It is caused by one of four related but antigenically distinct serotypes within the genus flavovirus. It is transmitted by Aedes aegypti mosquitoes and is endemic in many tropical regions of Asia, the Pacific, Central America and West Africa, with epidemics after severe rainy seasons. The first epidemics were reported in 1779, and a global pandemic began after World War II, particularly in...

Anticholinergic cholinolytic agents

Anticholinergic effects are produced by the following agents atropine and related compounds, including the belladonna alkaloids, such as scopolamine the synthetic quaternary ammonium compounds with anti-muscarinic action, such as homatropine, ipratropium and propantheline antidepressants (tricyclics) antipsychotics (phenothiazines) antiparkinsonian drugs (especially benztropine) Anticholinergic effects comprise three actions, namely

Poliomyelitis

Poliomyelitis has become rare in developed countries since the development of a successful vaccine in 1955. In developed countries, the occasional reported illness is most likely caused by mutation towards a virulent strain in a relative or recipient. Poliomyelitis is asymptomatic in 95 of cases. In the remainder, the features are usually similar to mild influenza and gastroenteritis. It occasionally produces aseptic meningitis and most importantly paralysis from destruction of motor neurones...

Pulmonary hypertension

Pulmonary hypertension is a common association of many lung diseases. It also follows a number of non-pulmonary disorders, especially those of a cardiac nature. Pulmonary hypertension is defined as an increase in the pulmonary artery pressure (PAP) above 30 15 mmHg (mean PAP > 20-25 mmHg). Cor pulmonale refers to right ventricular hypertrophy and or dilatation secondary to pulmonary disease and in response to pulmonary hypertension. There may or may not be overt right ventricular failure. The...

Many concomitant extrahepatic syndromes

Have also been reported, most commonly in hepatitis B. There have been associated autoimmune haemolytic anaemia cryoglobulinemia especially in chronic HCV infection sicca syndrome especially in chronic HCV infection immune-mediated renal disease in chronic HBV and especially HCV infection. Hepatitis type A virus (HAV, infectious hepatitis virus) is an RNA virus transmitted by faecal contamination. The incubation period is usually 3 5 weeks, and there is a viraemia with viral shedding for up to...

Multiple sclerosis

Multiple sclerosis (MS) is a condition of chronic patchy demyelination which occurs in the white matter in zones called plaques. These are of varying site and size within the CNS. Its aetiology is unknown, but it may be an autoimmune response to viral infection, possibly via molecular mimicry with a homologous sequence within the myelin protein. It mostly occurs in young adults who are predisposed because of certain genetic haplotypes, but these influences are only partly characterized....

Amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (motor neurone disease) is a condition of degeneration of the pyramidal motor neurones from the cortex as far as the anterior horn cells of the spinal cord. It is an uncommon condition of unknown aetiology, most commonly affecting middle-aged men. Clinical features comprise a slowly progressive weakness and wasting, associated with fasciculation, hyper-reflexia and muscle cramps. The process can be distal or proximal early, but progressive proximal involvement then...

Phlebitis

Dimercaprol (2,3-dimercaptopropanol, British anti-Lewisite, BAL) was designed to combat arsenic-containing military gas in the Second World War. Later, its use was extended to other heavy metal poisoning, particularly from lead and mercury. It is an oily pungent liquid, which is given intramuscularly and metabolized and excreted within 4 6 h. The individual doses are 3 5 mg kg (3 mg kg for arsenic, 4 mg kg for lead and 5 mg kg for mercury). The urine should be alkalinized concomitantly to...

Cardiovascular diseases

Many cardiovascular disorders are encountered so commonly in Intensive Care that they are regarded as 'core' to the specialty. These conditions include myocardial ischaemia and infarction, heart failure, arrhythmias, shock and hypertension. However, numerous other cardiovascular disorders are sometimes seen, and it is these which are considered in this book. They include arteriovenous malformations

Angioedema

Hereditary angioedema (HAE) is due to a deficiency of C inhibitor (Cj INH), a serine protease like many activated coagulation factors. HAE is an autosomal dominant condition, with affected heterozygotes having 5 30 of the normal concentration of Cj INH. Clinically, there are recurrent attacks of non-pitting oedema, lasting 48 72 h and affecting skin, respiratory tract and gut. The most dramatic feature is laryngeal oedema, causing potentially fatal upper airway obstruction. The oedema is not...

Renal cortical necrosis

Renal cortical necrosis refers to infarction of the entire renal cortex with consequent acute anuric renal failure. The juxtamedullary glomeruli probably survive and are responsible for the partial recovery seen in some patients. traditionally associated with prolonged shock or severe hypovolaemia classically associated with obstetric disasters. Clinically, there may be loin pain, hypotension and anuria, preceded sometimes by haematuria. Urinalysis shows casts (as in acute tubular necrosis),...

Antinuclear antibodies

Antinuclear antibodies (ANA) are most characteristically associated with SLE, but in fact they are also diagnostically useful in other autoimmune diseases, including Sjogren's syndrome, scleroderma and mixed connective tissue disease. Several nuclear antigens are recognized by autoantibodies in SLE, with the resultant circulating immune complexes able to injure a number of organs and structures, especially renal glomeruli. Antibodies to native double-strand DNA and soluble (extractable) nuclear...

Trauma in pregnancy

Trauma in pregnancy is the commonest cause of maternal death, although only 1 in 20 cases of maternal trauma requires hospitalization. Fetal risk is greater than maternal risk, but in general fetal loss is minimized if maternal health can be maintained. Trauma during pregnancy may present special problems of assessment and management. This is not just because two patients have to be simultaneously considered, but especially because of the altered abdominal anatomy and general physiology. While...

Signs of

proptosis and lid lag, with occasionally the more severe eye involvement of exophthalmos or even ophthalmoplegia hyperdynamic circulatory state Investigations show increased T4 and T3 and suppressed TSH levels. If there is associated hypoproteinaemia and thus decreased TBG, the free T4 level needs to be measured (or calculated). Hyperthyroidism is excluded by a normal TSH level, unless the patient has a TSH-secreting pituitary tumour (see below). Treatment options include antithyroid drugs...

Visual impairment with

visual loss (sometimes permanent) Treatment is with CSF drainage, diuretics or, if refractory, corticosteroids (in moderate doses for about 3 months). CSF drainage may be by repeated lumbar puncture (e.g. 20 40 mL taken several times weekly) or a shunt (e.g. lumboperitoneal). Suitable diuretics include frusemide or acetazolamide. Glycerol orally can be effective. Weight reduction is recommended. Surgical decompression is sometimes required, e.g. optic nerve sheath decompression if vision is...

Pulmonary venoocclusive disease

Pulmonary veno-occlusive disease may be seen in a number of settings. In primary pulmonary hypertension (PPH), about 5 of patients have involvement predominantly affecting the pulmonary veins instead of the arteries, with intimal proliferation, thrombosis, obliteration and fibrosis. In these cases, it appears to be an uncommon variant of PPH. Sometimes, the condition may be seen in association with mediastinal fibrosis (see Mediastinum). It has also been reported in collagen-vascular diseases,...

Islet cell tumour

Islet cell tumours of the pancreas cause fasting hypoglycaemia, which is associated with abnormally high (i.e. non-suppressed) insulin levels and which displays Whipple's triad. Whipple's triad consists of hypoglycaemia, which displays typical clinical features (especially neuroglycopenia) with an appropriately low blood sugar with relief of symptoms with therapy which restores the blood sugar to normal. The islet cell tumour is thus an insulinoma. Most such tumours (90 ) are single, small and...

Biliary cirrhosis see also Cholangitis and

Biliary cirrhosis may be either primary or secondary. Primary biliary cirrhosis is an autoimmune disease. It is thus also associated with other autoimmune diseases, particularly scleroderma, CREST syndrome, Sjogren's syndrome and renal tubular acidosis. There is a genetic predisposition because of the association with the HLA-DR8 haplotype. Clinical features of primary biliary cirrhosis typically are manifest in women aged 30 50 y. There is the gradual onset of pruritus, fatigue and increased...

Myasthenia gravis

Myasthenia gravis is a condition of muscle weakness due to impaired neuromuscular transmission. It is caused by autoantibodies to a subunit of the acetylcholine receptor on the post-junctional muscle membrane. It occurs primarily in younger women or older men. In about 10 of cases, there is an associated thymic tumour (thymoma). There is typically a gradual onset of muscle fatigue, characteristically with increasing weakness with repetitive use. It may range in severity from mild and local to...

Erythema multiforme

Erythema multiforme is one of the toxic erythemas. It is an acute hypersensitivity reaction of skin and mucous membranes, following infections, drugs and some other stimuli. Infections may be bacterial (streptococcal, TB), viral (HSV, influenza, mumps), fungal or due to mycoplasma. Drugs most commonly include barbiturates, penicillin, sulfonamides, phenytoin. Other stimuli include collagen-vascular diseases, malignancy, graft-versus-host reaction. There is a characteristic inner lesion of a red...

Organspecific such as

primary angiitis or arteritis of the central nervous system neutrophilic dermatoses (e.g. Beh et's syndrome q.v.) chronic lymphocytic vasculitis (e.g. pyoderma gangrenosum q.v.). There a number of specific types of vasculitis, affecting mostly large vessels affecting primarily medium-sized vessels affecting primarily small vessels associated with thrombosis associated with vessel wall degeneration.

Autoimmune haemolytic anaemia

This may be either idiopathic or secondary to conditions such as lymphoma, multiple myeloma, SLE, ulcerative colitis. The direct Coombs test is positive, and there may be jaundice, hepatosplenomegaly and lymphadenopathy in severe cases. In addition to spherocytosis, there is macrocytosis and sometimes leukopenia or thrombocytopenia. The condition usually responds to corticosteroids, but sometimes splenectomy or immunosuppressive therapy may be needed.

Beta2microglobulin

Beta2-microglobulin is the beta or light-chain of the HLA-Class I molecule required for cell-cell recognition. It is a small protein of 11.5 kd and is present on most cell membranes though not on mature red blood cells. There is considerable amino acid sequence homology between beta2-microglobulin, the heavy chain of the MHC Class I antigen and the constant region of the heavy chain of IgG. Beta2-microglobulin is released during cell breakdown and is then metabolized and cleared by the kidney....

Food poisoning

Although food poisoning is a very common condition, its presentation in Intensive Care is uncommon and moreover it may take a number of unusual forms. The types of food poisoning considered in this book include Chinese-restaurant syndrome In addition, some aspects of food poisoning are of an infectious nature and are considered more generally (e.g. see Diarrhoea and Norwalk virus). Haddad LM, Shannon MW, Winchester JF (eds) 1997 Clinical Management of Poisoning and Drug Overdose. 3rd edition....

Idiosyncratic mechanisms are involved with

analgesics (especially NSAIDs, classically phenylbutazone but also indomethacin) antibiotics (ampicillin, chloramphenicol) tranquillizers (especially phenothiazines and most recently clozapine). Clinically, the neutropenia may be found coincidentally or because of an infection. Such infections may produce diminished signs because of the absence of pus, and they typically respond poorly to antibiotics. They particularly involve the skin, respiratory tract and urinary tract, and they are due to...

Bleomycin

Bleomycin is a mixture of related glycopeptides used in cancer chemotherapy, especially for squamous cell carcinomas, as well as for lymphoma and testicular cancer. It produces little bone marrow or immune suppression. Its unique action is to fragment DNA, and it is commonly used in multidrug combinations. Its side-effects include fever, stomatitis, alopecia, and rash with pruritus and vesiculation. In the Intensive Care Unit, two uncommon but important side-effects may be relevant. A fulminant...

Cardiac tumours

Cardiac tumours are relatively common, though most are asymptomatic and the diagnosis is often difficult. Cardiac tumours may be primary or secondary. histologically benign and are myxomas (see below), but occasionally a fibroma, lipoma or hamartoma (as in tuberous sclerosis) may occur. Rarely, primary tumours may be malignant, in which case they are usually sarcomas. Secondary tumours comprise at least 95 of cardiac neoplasms at autopsy and are found in about 10 of patients with terminal...

Lyme disease

Lyme disease is caused by the tick-borne spirochaete, Borrelia burgdorferi, and is the most common vector-borne disease in non-tropical developed countries. It was first observed in the town of Lyme in Connecticut in 1975, its causative agent was confirmed in 1983 and its genome sequenced in 1997, and it is now widely observed around the world. Animal reservoirs include numerous wild and domestic animals and birds, and a variety of tick species and perhaps other insect vectors become infected....

Urticaria

There are a number of urticarial conditions, but apart from hives they are uncommon. 1. Urticaria thus usually refers to hives, which are areas of transient, localized, pruritic oedema, varying in size from 1 20 cm and in number from one to more than 100. They are usually caused by food sensitivity (mostly due to the degranulating chemicals used as colouring and flavouring agents) and aspirin. The main treatment of hives and indeed of urticaria in general is with antihistamines and if severe...

Echinococcosis

Echinococcosis (hydatid disease) refers to human infection with the cysts of the dog tapeworm, Echinococcus granulosus. Other forms of echinococcus are found in other animals, e.g. foxes, in some parts of the world. The adult cestode lives in the dog's intestine, and eggs passed in the faeces are ingested by intermediate hosts, usually sheep but occasionally incidentally humans. The cycle is normally completed when dogs eat an infected carcass or offal of one of the intermediate hosts. Hydatid...

Lassa fever

Lassa fever is one of the four forms of viral haemorrhagic fever transmitted from person to person (see Ebola haemorrhagic fever). It was first recognized in 1970 in Nigeria and is known to have a rodent reservoir, with person to person spread following human ingestion of contaminated food. The pathogenesis involves viral interaction with and damage to endothelial cells and platelets, giving rise to a generalized capillary leak. The incubation period is 6 21 days, which provides sufficient time...

Gingivitis

Gingivitis is commonly of dental origin. The organisms involved are usually anaerobic upper respiratory tract flora (peptostreptococci, fusobacteria, bacteroides). In hospital patients, Gram-negative bacilli and staphylococci may also be involved. Uncommon causes include viruses or actinomyces. Gingivitis may also be associated with i.e. sublingual cellulitis seen in bleeding disorders or scurvy classically occurring with phenytoin or more recently with cyclosporin and calcium channel blockers...

Mushroom poisoning

Mushroom poisoning is a worldwide problem because of the difficulty in identifying the many species which grow in the wild. Commercially available mushrooms, however, are cultured. Poisoning also occurs because of the 'recreational' use of mushrooms for their hallucinogenic properties. In fact, only about 1 of mushrooms are poisonous. The term 'mushroom' is non-scientific and refers to the edible type of fungus, whereas the equally lay term 'toadstool' refers to any poisonous variety. Mushrooms...

Lymphomatoid granulomatosis is an

Uncommon condition with histological features resembling both Wegener's granulomatosis and lymphoma. There is a pulmonary infiltrate which is angiocentric, destructive and lymphoreticular, with atypical cells showing mitoses. Similar lesions may be found in other organs, especially skin and sometimes the mouth. Respiratory symptoms include cough, sputum and dyspnoea. The chest X-ray shows bilateral infiltrates, rounded lesions similar to metastases and cavitation. No consistently effective...

Renal cystic disease

Renal cystic disease comprises a wide variety of conditions. 1. Simple cysts are fluid-filled, epithelial-lined structures. They are clinically silent and are found in about 50 of older patients. 2. Acquired cystic disease refers to the presence of more than five cysts, accompanied by renal impairment and usually with small scarred kidneys. This process arises in the proximal tubules and occurs in about 50 of patients on long-term dialysis. These cysts can cause haematuria, loin pain and...

Renal failure

The neuropathy is similar to that produced by many toxic agents and indeed drugs. The skin pigmentation is bronze in colour and is the characteristic skin lesion, with 'rain drop' areas of hypopigmentation due to hypomelanotic macules. In addition to keratoses, there may be skin cancer, either basal cell carcinoma or squamous cell carcinoma. Although Bowen's disease, which resembles superficial basal cell carcinoma, usually arises from solar exposure, when it follows arsenic ingestion it can...

Dermatitis

Dermatitis is a very general term encompassing a number of more specific entities. 1. Atopic dermatitis (atopic eczema) is well known. It may have a complication called Kaposi's varicelliform eruption due to dissemination of HSV or VZV infection. Treatment of severe refractory disease includes several options. Both immunosuppression with a variety of agents and traditional Chinese medicinal herbs have been reported to be helpful. 2. Contact dermatitis may be due to allergy, irritation or...

Acquired immunodeficiency syndrome

Acquired immunodeficiency syndrome (AIDS) has become a well recognized entity throughout all of clinical medicine and beyond. In Intensive Care, as in many other specialties, the most common presenting features of AIDS are opportunistic infections. Patients presenting with these, even if their HIV status is unknown and provided they have no other known immunodeficiency, are generally not difficult to recognize as likely to have AIDS. These infections are often unusually chronic, recurrent or...

Acute liver failure with damage resembling hepatitis

The toxic effects of amphetamine are not simply related to excess dosage, as they can be either severe following a dose as low as 30 mg (which is only a maximum daily therapeutic dose), or not fatal at doses as high as 300 mg. Acute treatment consists of urinary acidification (e.g. with ammonium chloride, which increases excretion), sedation and blood pressure control (e.g. with sodium nitroprusside). Dantrolene and serotonin antagonists may be useful in the management of MDMA-induced...

Acute pulmonary oedema

Pulmonary oedema is defined as an increased amount of extravascular fluid (water and solute) in the lung, where it may be interstitial or alveolar or both. Pulmonary oedema is one of the commonest respiratory disorders and may follow a wide variety of local and systemic insults. Although pulmonary oedema due to left heart failure is the classical clinical picture, pulmonary oedema also occurs in a number of other common settings. In these, the left atrial pressure may be normal or even low....

Alpha1antitrypsin deficiency

Alpha1-antitrypsin deficiency was first described as a serum electrophoretic abnormality by Laurell and Eriksson in Scandinavia in 1963 and was soon recognized to be associated with chronic airway obstruction. Alpha1-antitrypsin (a1 AT) is one of the major plasma antiproteases. It is thus a member of the serpin superfamily, inhibitors controlling coagulation, fibrinolysis and complement activation. It is also an acute phase reactact. It has 392 amino acid sequence, and its molecular weight is...

Amenorrhoea

Primary amenorrhoea (i.e. failure of periods to commence) is relatively rare. Secondary amenorrhoea (i.e. the cessation of periods) is of much greater clinical importance. The commonest causes are pregnancy or the menopause, but otherwise the condition is probably due to anovulation. Failure of ovulation can be due to a variety of disorders and can occur at several levels, namely hypothalamus (this probably includes athlete's amenorrhoea, which appears to be a reversible neuro-endocrine...

An unusual variant is necrotizing sarcoid granulomatosis with pulmonary arteritis

Extrapulmonary manifestations are numerous and varied, and they may be apparent in Skin. Erythema nodosum is seen in 90 of patients with stage I disease. Sometimes, there may be skin granulomas, nodules or lupus pernio (usually in stage III disease). Eyes are involved in 25 of patients. Typically, there is uveitis with painless photophobia and lacrimation. Classically but uncommonly, there may be uveoparotid fever (with associated salivary gland enlargement, systemic symptoms, meningitis and...

Anaemia due to blood loss

Although blood loss is usually readily apparent, sometimes it may be occult, especially from the gastrointestinal tract. Blood loss whether overt or occult is most commonly from the gastrointestinal tract or in women from obstetric or gynaecological causes. In Intensive Care patients, it may be iatrogenic. Rarer causes of a similar anaemia include long-distance athletic performance paroxysmal nocturnal haemoglobinuria. In acute blood loss, the haemoglobin concentration may take up to three days...

Anaemia due to haemolysis

Haemolytic anaemia occurs when the rate of red blood cell destruction exceeds the bone marrow's productive capacity. Thus, although the normal life-span of red blood cells in the circulation is about 115 days (with thus about 1 or the equivalent of 50 mL of blood being destroyed and replaced daily), the marrow reserve is such that it can compensate for a red blood cell life-span of 30 days or less. The marrow reserve is thus considerable, being normally about 5-fold and rising to perhaps 8fold...

Angiotensin II receptor antagonists

(ARAs), i.e. losartan, irbesartan and related compounds, target the ATj receptor. They thus provide more complete angiotensin blockade than do the ACE inhibitors, because angiotensin can also be formed to some extent via pathways other than renin. Since the angiotensin receptor antagonists do not block the inactivation of bradykinin like the ACE inhibitors do, they were not expected to produce cough or angioedema, but this early promise has not been borne out in practice. On the other hand, the...

Ankylosing spondylitis

Ankylosing spondylitis is a subgroup of the spondyloarthropathies (q.v.), conditions characterized by the combination of sacroiliitis and seronegative peripheral arthropathy. Although the aetiology is unknown, it may possibly be precipitated by a number of bacterial antigens. There is also a presumed immunogenetic susceptibility, as evidenced by clustering in families and some ethnic groups. There is a strong correlation with the HLA antigen B27. Thus, 95 of patients with ankylosing spondylitis...

Antiphospholipid syndrome

The antiphospholipid syndrome (APS) is a hypercoagulable state associated with the presence of anticardiolipin antibody, lupus anticoagulant and possibly other antibodies. In the 1950s, some patients with SLE were observed to have a long clotting time but a paradoxical thrombotic tendency. In the 1970s, the responsible substance became referred to as the lupus anticoagulant (LA). Subsequently, LA was observed in other (especially autoimmune) diseases and even in some healthy people, so that it...

Antithrombotic therapy is recommended Bibliography

Burton JL 1988 Livedo reticularis, porcelain-white scars, and cerebral thromboses. Lancet 1 1263. Copeman PW 1975 Livedo reticularis signs in the skin of disturbance of blood viscosity and of blood flow. Br J Dermatol 93 519. Klein K, Pittelkow M 1992 Tissue plasminogen activator for the treatment of livedoid vasculitis. Mayo Clin Proc 67 923. Schroeter AL, Diaz-Perez JL, Winkelmann RK et al 1975 Livedo vasculitis (the vasculitis of atrophie blanche) immunohistopathologic study. Arch Dermatol...

Arsenic

Arsenic (As, atomic number 33, atomic weight 75) is a non-metallic element in the nitrogen family. Although arsenic-containing compounds have been known since antiquity and arsenic is widely distributed in nature in various forms, the element was not identified until 1649. Arsenicals are used in herbicides, pesticides and various manufacturing processes. Arsenic poisoning may be occupational, accidental or deliberate (either as a classical criminal agent or as a military poison). Toxicity from...

Atrial natriuretic factor

Atrial natriuretic factor (ANF) is a peptide which is stored in the atrial myocardial cells and released during atrial dilatation. It is one of a family of five structurally related natriuretic peptides of 22 53 amino acids, each peptide being secreted by different tissues. ANP is a natural antagonist to the renin angiotensin aldosterone system and promotes renal excretion of sodium and water. It is also a potent vasodilator and may thus play a homeostatic role in vascular control. Excess...

Barotrauma s ee also Diving

Barotrauma refers to air forced outside the normal air spaces. It thus comprises gas embolism (via pulmonary veins). More subtle abnormalities may be seen histologically or on CT scan and include pseudocysts (pneumatoceles). Barotrauma is a potential complication of mechanical ventilation, especially if inspired pressures or volumes are high or excessive PEEP is used. An alveolar distending pressure of 30 35 mmHg is the injury threshold in most animal studies, so that the end-inspiratory...

Bells palsy

Bell's palsy refers to paralysis of the facial (VII) nerve. It is produced by inflammation in the facial canal within the temporal bone, but the cause of this process is uncertain. Recently, herpes simplex virus type 1 has been implicated. There is the rapid onset of paralysis, which is sometimes complete. There is no sensory change, though there may be impaired lacrimation, salivation and taste. The differential diagnosis includes 7th nerve herpes zoster (Ramsay Hunt neoplastic or vascular...

Bence Jones protein see also Multiple

Bence Jones protein is a low molecular weight protein originally described in the urine of patients with multiple myeloma. It was noted to coagulate on gentle heating of the urine but to redissolve on boiling, only to precipitate again on cooling below 60 C. Its presence is virtually pathognomonic of multiple myeloma, though it is present in only 50 of such cases. The urine shows a positive dipstick test for protein, and there is a single band on urine electrophoresis. The protein is also...

Bronchiectasis

Bronchiectasis is defined on anatomical grounds as chronic abnormal dilatation of larger bronchi. This process comprises airway obstruction and damage following chronic inflammation, because the pooling of bronchial secretions rich in inflammatory products and in released intracellular proteases weakens the bronchial wall. In addition to severe, necrotizing lung infections, the aetiology probably also includes congenital factors. The association of bronchiectasis with congenital dextrocardia...

Bronchiolitis obliterans

Bronchiolitis obliterans (BO) (obliterative bronchiolitis, bronchiolitis fibrosa obliterans) is a rare condition and probably a very severe form of chronic obstructive bronchitis with pathological changes implied by its name, namely chronic organizing inflammation of small airways. Its pathogenesis is presumably bronchiolar epithelial injury followed by an excessively proliferative repair process. It is most usually due to the inhalation a few weeks previously of a toxic gas, for example an...

Burns respiratory complications

The respiratory complications of burns (inhalation injury) can result in significant morbidity and mortality in those initially surviving a fire. Respiratory tract injury results from the inhalation of products of combustion, which may be numerous, and has an even greater impact on mortality than the two important factors in burn injury of patient age and surface area involved. Smoke, the most obvious such product, is a suspension of carbon particles in air and other gases. The particles are...

Carbon monoxide

Carbon monoxide is a colourless, odourless, non-irritant and flammable gas with physical properties similar to nitrogen. It is produced from the incomplete combustion of carbon- containing fuels and is thus a common product in motor vehicle exhausts, faulty domestic heating and cooking devices, and in industry. In most countries, its predominant source is motor vehicle exhaust fumes, from which death can occur within 15 min if inside a confined space. Carbon monoxide is the most common lethal...

Cellmediated immunodeficiency

This is manifested as impaired delayed hypersensitivity with proneness to infections. Infections are frequent and severe and may be due to many different organisms, especially opportunists (e.g. candida, pneumocystis), Gram-negative bacteria and viruses. Primary deficiencies are sometimes inherited and include severe combined immunodeficiency disease (SCID) and its several variants the Wiskott-Aldrich syndrome, an X-linked disorder with associated eczema, thrombocytopenia and lymphoid cancers...

Chelating agents

A chelate is a complex compound with a central metal atom attached to a larger molecule (a ligand) in a ring structure. A chelating agent refers to the ligand which can attach to the metal ion at two or more points, thus forming a ring. Chelates are more stable than non-chelated compounds of comparable composition. Haemoglobin and chlorophyll are examples of chelate compounds in nature. Chelates are widely used in industrial and laboratory processes. In clinical medicine, chelating agents are...

Chemical poisoning

Chemical poisoning due to drug overdosage is a very commonly encountered problem in Intensive Care and its management principles are well known. However, many other chemical agents, generally of a non-therapeutic nature, may cause uncommon forms of poisoning following ingestion or other exposure. In particular, chemical exposure is a common environmental hazard in many parts of the world and in many industrial or accidental situations. Important poisonings or exposures described in this book...

Cholangitis

Acute cholangitis is usually associated with biliary obstruction, and this in turn is usually due to choledocholithiasis. Acute cholecystitis is due to cystic duct obstruction, and this in turn is virtually always due to cholelithiasis. However, most gallstones remain silent. The clinical features are dominated by biliary colic, i.e. severe pain in the right upper quadrant, rapid in onset, constant in nature (and thus not true colic), lasting up to one hour and associated with nausea, vomiting...

Chronic cholangitis is also usually due to biliary

Duct obstruction, but the causes include stricture or carcinoma as well as stones. Recurrent pyogenic cholangitis may also occur. This is occasionally secondary to intestinal parasites. Sclerosing cholangitis may sometimes be seen, involving both intrahepatic and extrahepatic bile ducts. This is a condition of unknown aetiology, but it is mostly associated with ulcerative colitis. It carries a 30 mortality over 5 years. The clinical features of chronic cholangitis include jaundice, fever,...

Coma

There is hyperkalaemia, myoglobinuria, increased lactate, increased creatine kinase, and the hypercapnia is out of proportion to a seemingly adequate ventilation. Treatment involves cooling, hyperventilation, oxygenation and therapy for abnormalities of electrolytes (e.g. hyperkalaemia) and acid base (e.g. metabolic acidosis). Most importantly, specific therapy is available with dantrolene, which decreases calcium ion release from the sarcoplasmic reticulum and thus decreases muscle...

Complement deficiency

The complement system is one of the four plasma enzyme cascades and together with the coagulation, fibrinolysis and kinin systems, it is involved in the bodily responses to injury. In particular, the complement system provides the major link between the process of inflammation and the immune system. It is thus involved not only in host resistance to infection, both immunological and nonspecific, but also in the mechanisms of tissue injury. The 18 plasma proteins of the complement system produce...

Creutzfeldt Jakob disease

Creutzfeldt Jakob disease (CJ disease, CJD) is an encephalopathy due to infection with a small transmissible proteinaceous particle called a prion. It is the human form of transmissible dementia, generally transmitted in nature by ingestion of infected animal tissues. It is related to the human disease, kuru, and to the animal diseases, scrapie and bovine spongiform encephalopathy (BSE, 'mad cow disease'). It is still a mystery how a variant of a normal cell membrane protein without RNA or DNA...

Cushings syndrome

Cushing's syndrome refers to adrenal cortical hyperactivity. excess adrenal stimulation intrinsic adrenal overactivity iatrogenic administration of corticosteroids in pharmacological doses. 1. Excess adrenal stimulation arises from excess ACTH, which may be secreted either by the pituitary (Cushing's disease) or ectopically. Excess pituitary secretion of ACTH causes bilateral adrenal hyperplasia and is responsible for two thirds of the cases of Cushing's syndrome. The original pituitary cause...

Damage to supporting structures occurs with

hereditary haemorrhagic telangiectasia (q.v.) amyloid (see Multiple Myeloma) hereditary connective tissue disorders Ehlers Danlos syndrome, Marfan's syndrome (q.v.), pseudoxanthoma elasticum. Miscellaneous conditions primarily include auto-erythrocyte purpura. This is an unusual and uncommon condition in middle-aged women. It is manifest as large painful subcutaneous haematomas. Its name derives from its reproduction by subcutaneous injection of the patient's own red blood cells.

Dermatology

The care of skin disorders is mostly undertaken in the ambulatory setting, and it is rare for a dermatological condition to be the cause of an admission to an Intensive Care Unit. However, their frequency in the population means that many seriously ill patients have a concomitant skin disorder. Moreover, the skin is an important target organ for a variety of complications of serious illnesses, especially drug reactions. Yet dermatological problems retain perhaps a greater air of mystery for the...

Differential diagnosis of hyponatraemia

Increased urine Na+ refers to > 20 mmol L and decreased urine Na+ refers to < 15 mmol L. Increased urine osmolality refers to > 200 mOsm kg. Increased urine Na+ refers to > 20 mmol L and decreased urine Na+ refers to < 15 mmol L. Increased urine osmolality refers to > 200 mOsm kg. Treatment is primarily with water restriction. Saline may be cautiously administered in severe cases but clearly must be more hypertonic than the urine, so that isotonic saline is generally unsuitable....

Diffuse fibrosing alveolitis

Diffuse fibrosing alveolitis (idiopathic pulmonary fibrosis, interstitial pneumonitis, cryptogenic fibrosing alveolitis, Hamman Rich syndrome) is a form of progressive diffuse inflammation distal to the terminal bronchiole. Although its aetiology is uncertain and no single pathogenetic mechanism has yet been defined, there are common histological, radiological and clinical features exhibited by most patients with this condition, justifying its consideration as a separate entity. However, it may...

Dioxins

A dioxin is a chemical compound consisting of two benzene rings connected by a pair of oxygen atoms. Since each ring contains 8 carbon atoms which can each bind to a hydrogen or other atom (the most concerning to health being chlorine), up to 75 isomers are possible. Dioxins are usually formed as a byproduct of the manufacture of herbicides based on 2,4,5-trichlorophenol and are the most toxic of artificial substances. The term dioxin particularly refers to one specific dioxin...