Elimination of small ruminant lentivirus infection from sheep flocks and goat herds aided by health schemes in Great Britain.

Over a period of 11 years, 33 sheep or goat holdings lost their maedi-visna or caprine arthritis-encephalitis accredited status (mean 2.8 per year [0.09 per cent] of the accredited holdings in Great Britain). Of these, 22 sheep flocks and two goat herds eradicated the infection and regained their accredited status. In addition, 10 sheep flocks and two goat herds managed to eradicate infection, having joined the scheme with infected animals. In flocks and herds with a high initial prevalence of infection, the adoption of an indirect ELISA, with greater sensitivity than the agar gel immunodiffusion test, improved success rates. A strategy was devised to interpret the ELISA results depending upon the prevalence of infection at the time. Eighteen of the 33 flocks/herds (54.5 per cent) that had introductions of infection also owned non-accredited stock.

Microalbuminuria as identified by a spot morning urine specimen in non-insulin-treated diabetes: an eight-year follow-up study.

This study followed up a cohort of patients with microalbuminuria identified on a spot morning urine sample 8 years earlier and aimed to determine if a spot morning urinary albumin concentration was able to identify patients with non-insulin treated diabetes at increased risk of mortality and progression to nephropathy. In 1984, 47 of 216 patients chosen by random selection from our teaching hospital-based diabetes clinic were identified as having microalbuminuria (urinary albumin concentration 35-300 micrograms ml-1). Subjects were compared with an age-matched control group from the 1984 cohort who did not have microalbuminuria. Eight years later, 22 of 47 (46.8%) patients with microalbuminuria had died compared to 10 of 47 (21.3%) patients without albuminuria (p < 0.05). The majority of deaths were from cardiovascular disease (53.1%). Logistic regression showed microalbuminuria to be an independent predictor of mortality, not influenced by age, duration of diabetes, blood pressure, glycosylated haemoglobin or creatinine at the initial examination. Eight years later, in the group with initial microalbuminuria, eight still had microalbuminuria and five patients had developed nephropathy. In the group without albuminuria in 1984, only one patient had progressed to microalbuminuria and no patients to nephropathy. In conclusion, a spot urinary albumin concentration is of value in identifying patients with an increased risk of mortality or progression to nephropathy, and is simple to obtain at a clinic.

Prevalence of hypertension and albuminuria in a teaching hospital diabetes clinic.

The prevalence of hypertension and its relationship to nephropathy were measured in a hospital-based diabetic clinic. Six hundred patients (300 insulin treated, 300 non-insulin treated) were randomly selected from a clinic population of 1054 insulin treated and 1039 non-insulin treated subjects. Eighty-three percent of patients with insulin treated diabetes and 72% of patients with non-insulin treated diabetes were studied. Blood pressure data from the Belfast MONICA project were used for the control group. In patients with insulin treated diabetes (age 25-64 years) the prevalence of a systolic blood pressure > 160 mmHg or a diastolic blood pressure > 95 mmHg or on treatment for hypertension (WHO criteria) was 19.1% in males (NS, vs. control group) and 17.8% in females (NS); the prevalence of a systolic blood pressure > 140 mmHg and diastolic blood pressure > 90 mmHg was 17.6% in males (NS, vs. control group) and 9.5% in females (NS). In patients with non-insulin treated diabetes (age 35-65 years) the prevalence of hypertension by WHO criteria (see above) was 26.8% in males (NS, vs. control group) and 28.9% in females (NS); the prevalence of a systolic blood pressure > 140 mmHg and diastolic blood pressure > 90 mmHg was 21.4% in males (NS, vs. control group) and 17.8% in females (NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Is a random urinary albumin concentration a useful screening test in insulin-treated diabetic patients?

The debate continues on how to screen for microalbuminuria in clinical practice in patients with insulin-dependent diabetes mellitus. Our study assesses the value of a spot morning urine specimen obtained at a clinic visit. In 1984, as part of a randomised survey of our diabetes clinic, 43 of 249 patients with insulin treated diabetes mellitus, were found to have microalbuminuria (urinary albumin concentration 35-300 ug ml-1) on a spot morning urine sample. These subjects were compared with an age-matched control group from the 1984 cohort who did not have microalbuminuria. Eight years later, in the group with microalbuminuria, 10 had died compared to six in the control group (p = 0.17) with 62.5% of all deaths being from cardiovascular disease. In the group with microalbuminuria, 10 of 27 still had incipient nephropathy while five had progressed to nephropathy. In the group without microalbuminuria only three of 33 patients had progressed to microalbuminuria while none had progressed to nephropathy. In conclusion a spot morning urine sample is a useful screening test to identify patients at risk of progression to nephropathy.

Studies on the pathogenesis of hypertension in Cushing's disease and acromegaly.

The pathogenesis of the hypertension associated with Cushing's syndrome and with acromegaly is poorly understood. We have investigated the possible roles of sodium retention, activation of the renin-angiotensin system and increased sympathetic nervous system activity in untreated patients. In 11 patients with Cushing's disease, seven of whom were hypertensive, total exchangeable sodium was normal despite increased levels of the mineralocorticoid hormones, 11-deoxy-corticosterone and corticosterone. The renin-angiotensin system was also normal. Cardiac sensitivity to the beta-receptor agonist isoprenaline was increased, but this was not due to an increase in beta-adrenoceptor density. Hypertension in Cushing's disease is neither sodium-dependent nor angiotensin II-mediated, but increased cardiac sensitivity to catecholamines, by increasing cardiac output, may contribute to the pathogenesis of hypertension. In nine patients with acromegaly (three of whom were hypertensive) total exchangeable sodium was elevated. Although no correlation between blood pressure and exchangeable sodium was found, hypertension in acromegaly is probably sodium dependent. No evidence was found for a pathogenetic role for either the renin-angiotensin-aldosterone or the sympathetic nervous system.

Ascertainment and natural history of treated acromegaly in Northern Ireland.

The prevalence of known cases of acromegaly in Northern Ireland in 1984 was 6.3 per 100,000 population. The incidence of newly-diagnosed cases over the preceding 25 years was 5.5 patients per year, or 0.4 patients per 100,000 population per year. This rate would be equivalent to about 200 new cases per year in the United Kingdom. Four options have been available to most of these patients--surgical hypophysectomy (transfrontal or transsphenoidal), pituitary radiotherapy (usually external cobalt beam), drug treatment with bromocriptine, or no treatment. Choice of treatment has been mainly influenced by tumour size, with the larger pituitary adenomas having surgery initially. No single form of treatment has been successful in achieving a clinical remission or cure in more than a minority of cases. The most successful outcome has been where total pituitary ablation has been achieved. Life-table analysis for the whole group shows life expectancy which is not markedly different for that of an age-matched population from Northern Ireland. Morbidity related to long term osteoarthritis and treatment complications remain a major problem. The incidence of malignant tumours is higher than would be expected.

Renal artery stenosis in hypertensive diabetic patients.

The prevalence of secondary forms of hypertension in diabetes is unknown. One hundred and five of 465 patients randomly selected from a diabetic clinic population were found to be hypertensive. Hypertensive patients aged less than 70 years were screened for renal artery stenosis using intravenous digital subtraction angiography. Two angiograms were technically unsatisfactory. All 18 insulin-dependent patients successfully screened had normal renal arteriograms. Five of 24 non-insulin-dependent patients had unilateral renal artery stenosis but functional tests did not clearly suggest that renal artery stenosis was causing the hypertension in these cases. No patient was referred for surgery or angioplasty. We conclude that renal artery stenosis is common in hypertensive non-insulin-dependent diabetics but may not, in many cases, be the cause of the hypertension. The criteria for investigating diabetic hypertensives for renal artery stenosis should be no different from those used in the general hypertensive population.