Geoffrey Gill

Characteristics and mortality of severe hyponatraemia – a hospital‐based study

Objective  To determine the characteristics, causes and outcome of severe hyponatraemia (< 125 mmol/l) in hospitalized patients, and to identify mortality predictors.

Investigation and management of severe hyponatraemia in a hospital setting

Aims: To evaluate the assessment and management of severe hyponatraemia in a large teaching hospital. Methods: Inpatients with serum sodium <125 mmol/l were identified prospectively from a laboratory database over a six month period. Notes were examined and data extracted. Case notes were carefully reviewed retrospectively by a consultant endocrinologist with regard to accuracy of the diagnosis and the appropriateness of investigations and management. Results: 104 patients with a serum sodium <125 mmol/l were identified. Mean (SD) age was 69 (14), 52% were female, mean hospital stay was 16 (12) days, and overall mortality 27%. Adequate investigations were rarely performed. Only 28 (26%) had plasma osmolality measured, 29 (27%) urine osmolality, 11 (10%) urinary sodium, 8 (8%) plasma cortisol, and 2 (2%) a short Synacthen test. Comparing the “ward” and “specialist review” diagnoses, there were significant discrepancies for “no cause found” (49% v 27%, p<0.001), alcohol (6% v 11% p<0.01), and syndrome of inappropriate antidiuresis (20% v 32%, p = 0.001). Treatment was often illogical with significant management errors in 33%. These included fluid restriction and intravenous saline given together (4%) and fluid restriction in diuretic induced hyponatraemia (6%). Mortality was higher in the group with management errors (41% v 20% p = 0.002). Conclusion: Severe hyponatraemia is a serious condition, but its investigation and evaluation is often inadequate. Some treatment patterns seem to be arbitrary and illogical, and are associated with higher mortality.

Gastrointestinal parasites in the immunocompromised.

Purpose of review Parasites and other infections have many effects on the gastrointestinal tract of individuals who are immunocompromised. Few reviews focus on parasitic infections, which are covered here. Recent findings The review first examines recent advances in our understanding of the taxonomy, diagnosis and treatment of pathogens such as cryptosporidia, cyclospora, isospora and microsporidia, which are recognized causes of diarrhoea in the immunocompromised, and discusses possible links between amoebiasis and HIV. The complex interactions of both intact and abnormal immune systems with helminth infections such as hookworm and strongyloidiasis, and with trematode infections such as schistosomiasis, are receiving increasing attention. These are discussed, together with the novel concept of using live helminths to treat inflammatory bowel disease. Summary Parasitic infections remain a significant problem for immunocompromised individuals in resource-poor settings, and further work is needed to develop accessible diagnostic tests and to improve our understanding and management of their pathogenic effects. New concepts about the interactions of helminths with host immunity suggest the need for collection of further epidemiological and clinical data to unravel the complexities of such immunological interactions.

The insulin dilemma in resource-limited countries. A way forward?

The International Insulin Foundation (IIF) has developed and validated a needs-assessment instrument called the Rapid Assessment Protocol for Insulin Access (RAPIA) which has been used in seven countries in four continents to analyse the constraints to delivering effective continuing care for people with diabetes. One major contributor to the difficulties in availability of insulin is a failure to use the least costly sources and types of insulin and other effective drugs for diabetes. The purchase of insulins can consume as much as 10% of government expenditure on drugs, this being highly sensitive to the selection of newer analogue insulins as first-choice options, which cost between three and 13 times more than biosynthetic human insulin. Insulin cartridges for use with injection pens further add to costs. Similar considerations apply to most of the newer treatments for people with type 2 diabetes, which may cost up to 40 times more than metformin and sulfonylureas, still considered first-line drugs by European and US guidelines. Both biosynthetic human insulin and the first-line oral hypoglycaemic drugs are available from generic manufacturers. With the present price differentials, there is thus a growing need for countries involved in tendering for sourcing insulin to be provided with the guarantees of Good Manufacturing Practice, quality and bioequivalence, which would come from a WHO Pre-Qualification Scheme as currently exists for a variety of drugs for chronic diseases, both communicable and non-communicable. The IIF has developed a position statement on the provision and choice of diabetes treatments in resource-limited settings which should be applicable wherever consideration of resources is a component of therapeutic decision making.

Evidence for affluence-related hypertension in urban Brazil

Cardiovascular diseases are a leading cause of mortality, and systemic hypertension is a major risk factor. There is an increasing prevalence of hypertension in urban areas of developing countries, due to lifestyle changes associated with economic transition and urbanisation. This study aimed to describe the prevalence and identify risk factors for hypertension in an urban area of South America (Coroa do Meio district in Aracaju, Sergipe State, north-east Brazil) and to examine intraurban hypertension prevalence differences. A cross-sectional survey of 400 adults aged 25 years and over was carried out. Information about health and lifestyle was obtained from a structured interview, followed by assessment of blood pressure (BP) and anthropometry. There were 31.8% (95% confidence interval 27.3–36.6%) participants with hypertension (defined as a systolic BP >140, diastolic BP >90 mmHg, or on antihypertensive medication). Hypertension was independently associated with older age, central obesity (greater waist-to-hip ratio), shorter height and residing in a high socio-economic residential area. Of the four neighbouring areas, hypertension prevalence was 52% in the area of highest income and education, compared with 19, 24 and 34% in the other three areas. The high prevalence of hypertension in this population, and the strong independent association with relative affluence, demonstrates the need for effective primary prevention of hypertension, targeted at modifiable risk factors.

Tropical diabetic hand syndrome

The tropical diabetic hand syndrome (TDHS) is a complication affecting patients with diabetes mellitus in the tropics. The syndrome encompasses a localized cellulitis with variable swelling and ulceration of the hands, to progressive, fulminant hand sepsis, and gangrene affecting the entire limb. TDHS is less well recognized than foot infections and not generally classified as a specific diabetes complication. Hand infection was first described in Nigeria in 1984. Since then, the majority of cases have been reported in the African continent and more recently in India. There is often a history of antecedent minor hand trauma (e.g. scratches or insect bites). Presentation to hospital is often delayed due to the patients’ unawareness of the potential risks, lack of concern because the initiating trauma might have been trivial, or decision to seek initial help from traditional healers. The first analytic study was done in Dar es Salaam, Tanzania, to characterize the epidemiology, clinical characteristics and risk factors of TDHS.

Serious hand sepsis and diabetes mellitus: specific tropical syndrome with western counterparts

Infection in the extremities of diabetic patients most commonly involves the feet and, at least in western societies, is often associated with chronic complications of diabetes. Severe hand infection, often culminating in amputation and even death, is, however, well‐described in tropical countries, where it may not be associated with any evidence of neuropathy or arterial insufficiency. Similar cases are described in the western literature but are more often associated with more severe antecedent trauma. The literature describing hand sepsis in diabetic patients both in tropical and in western practice is reviewed and we draw some conclusions about pathogenesis and treatment from the literature and from original data documenting the varying experience of hand sepsis in diabetic practice throughout Africa.

Leukocytosis as a predictor for non-infective mortality and morbidity

Leukocytosis (raised concentration of white cells in the blood) is commonly associated with infection or inflammation, but can occur in a wide variety of other conditions. Leukocytosis has also been linked with increased mortality and morbidity in a number of studies. We have systematically reviewed the relevant literature, which clearly demonstrates an association between leukocytosis and mortality-particularly due to cardiovascular or cerebrovascular causes. The mechanisms of this effect are uncertain but, when combined with other markers predictive of death, leukocytosis may contribute to modelling systems to predict in-patient mortality risk.

Long-term (20 years) outcome and mortality of Type 1 diabetic patients in Soweto, South Africa.

Aims  To assess the long‐term (20 years) mortality, with causes of death, in a cohort of Type 1 diabetic patients resident in Soweto, South Africa.

Tropical diabetic hand syndrome: Risk factors in an adult diabetes population

OBJECTIVES To determine risk factors for the tropical diabetic hand syndrome, a condition associated with significant morbidity and mortality in Africa. METHODS This was a case-control study of a Tanzanian diabetes population presenting with the syndrome during February 1998 to March 2000. A case patient was defined as any patient with diabetes presenting with hand cellulitis, ulceration, or gangrene. Control patients were randomly selected patients with diabetes who had no hand symptoms. RESULTS Thirty-one case patients and 96 control patients were identified. The median age of case patients was 52 years (range, 28--76 y); 58% were male; 4 patients (16%) died. Precipitating events included papule (n = 6), insect bites (n = 6), boils (n = 5), burns (n = 2), or trauma (n = 3). Case and control patients were similar for presence of micro- and macrovascular disease and occupation. On logistic regression analysis, independent risk factors were body mass index of 20 or less (odds ratio [OR] = 18.0; 95% confidence interval [CI] = 4.3--97.0; P < 0.001), peripheral neuropathy (OR = 23.0; 95% CI = 5.3--124.0; P < 0.001), or type I diabetes, (OR = 6.7; 95% CI = 2.0--24.0, P < 0.01). CONCLUSION The major risk factors for the tropical diabetic hand syndrome are intrinsically related to the underlying disease. Thus, prevention of hand infections may require aggressive glucose control, and education on hand care and the importance of seeing a doctor promptly at the onset of symptoms.