Familial juvenile hyperuricaemic nephropathy is not such a rare genetic metabolic purine disease in Britain

Renal disease is rare today in classic adult gout, and gout is rare in renal disease--especially in the young. Here we summarise studies in 158 patients from 31 kindreds diagnosed with familial juvenile hyperuricaemic nephropathy FJHN from a total of 230 kindred members studied in Great Britain. Some patients have been followed for up to 30 years, and allopurinol has ameliorated the progression of the renal disease in all 113 surviving members provided: They have been diagnosed and treated sufficiently early. Compliance with allopurinol treatment and diet has been as important as early recognition. Hypertension has been rigorously controlled. The use of oral contraceptives has been avoided, as has pregnancy in any female with a Glomelar Filtration Rate GFR <70 ml/min. The question arising is: Why is FJHN the most prevalent genetic purine disorder diagnosed in Britain? Is it a lack of awareness which needs to be improved Europe-wide?

Renal effects of amlodipine in normotensive renal transplant recipients

Renal effects of amlodipine in normotensive renal transplant recipients. The use of cyclosporin A (CsA) has improved the success of renal transplantation, but is associated with hypertension and significant renal toxicity. Previous reports suggest that calcium channel blockers may be useful in opposing the adverse effects of CsA. We have evaluated the effects of amlodipine (5 mg, once daily for 8 weeks) on renal function in 27 normotensive renal transplant recipients with stable renal function, in a double-blind, placebo-controlled, multicentre, cross over study. Amlodipine significantly reduced serum creatinine concentration relative to placebo (mean+/-SD: 168+/-65 vs 177+/-66 micromol/l; P=0.002) and there was a strong trend towards an increase in effective renal plasma flow on amlodipine relative to placebo (238+/-92 vs 217+/-87 ml/min; P=0.055). Glomerular filtration rate and lithium clearance were unaffected. Trough CsA blood concentration was unaffected. Amlodipine was well tolerated, with a low incidence of adverse events, and did not affect blood pressure or heart rate. In conclusion, amlodipine reduced serum creatinine in normotensive renal transplant recipients after only 8 weeks treatment, and was well tolerated in concomitant administration with CsA.

Modifying effects of amlodipine on cyclosporin A-induced changes in renal function in patients with psoriasis

OBJECTIVE

To assess the benefit of amlodipine, a calcium channel blocker, on renal function and vasoactive hormones in individuals with normal kidneys and blood pressure and who were being treated with cyclosporin A for refractory psoriasis.

DESIGN

An open-label, two-stage, longitudinal study was employed.

METHODS

Patients were divided into two groups: Group I received cyclosporin A, 5 mg/kg per day for 6 months titrated down to 2.5-3.5 mg/kg per day for 6 months, then concomitant amlodipine 5 mg/day for 6 months; and Group II received concomitant cyclosporin A, 5 mg/kg per day, and amlodipine, 5 mg/day, for 6 months. Blood pressure, serum creatinine, glomerular filtration rate, urinary magnesium, plasma renin activity and urinary kallikrein excretion were measured before and after treatment.

RESULTS

Eighteen patients were enrolled, and 12 completed the study. In Group I (n = 7), 12 months of cyclosporin A therapy significantly increased systolic blood pressure and significantly decreased glomerular filtration rate, plasma renin activity and active urinary kallikrein. Amlodipine reversed these changes. In Group II (n = 5), 6 months of concomitant cyclosporin A and amlodipine significantly reduced active urinary kallikrein levels. No significant changes occurred in the other measured parameters in either group.

CONCLUSIONS

Cyclosporin A produces a sustained and significant fall in glomerular filtration rate and urinary kallikrein excretion, even in patients with normal kidneys and blood pressure. Amlodipine is potentially capable of reversing these nephrotoxic effects.

Presymptomatic detection of familial juvenile hyperuricaemic nephropathy in children

We studied 34 apparently healthy children and 2 propositi from kindreds with familial juvenile hyperuricaemic nephropathy (FJHN) - a disorder characterised by early onset, hyperuricaemia, gout, familial renal disease and a similarly low urate clearance relative to glomerular filtration rate (GFR) [fractional excretion of uric acid (FEur) 5.1+/-1.6%] in young men and women. In addition to the propositi, 17 asymptomatic children were hyperuricaemic -- mean plasma urate (368+/-30 micromol/l), twice that of controls (154+/-41 micromol/l). Eight of them had a normal GFR ( > 80 ml/min per 1.73 m2), and 11 renal dysfunction, which was severe in 5. The FEur in the 14 hyperuricaemic children with a GFR > 50 ml/min was 5.0+/-0.5% and in the 5 with a GFR < or =50 ml/min was still low (11.5+/-0.2%) compared with controls (18.4+/-5.1%). The 17 normouricaemic children (185+/-37 micromol/l) had a normal GFR (>80 ml/min) and FEur (14.0+/-5.3%). The results highlight the dominant inheritance, absence of the usual child/adult difference in FEur in FJHN and presence of hyperuricaemia without renal disease in 42% of affected children, but not vice versa. Since early allopurinol treatment may retard progression to end-stage renal failure, screening of all relatives in FJHN kindreds is essential.

Is blood pressure related to kidney size and shape?

OBJECTIVE

To examine the relationship between blood pressure and the size and shape of the kidneys in healthy volunteers from the community.

DESIGN

A cross-sectional community-based study of normal volunteers in Portsmouth City, Hampshire, UK.

SUBJECTS

Subjects numbered 185 (99 female), aged 19-66 years.

RESULTS

Blood pressure was higher in men, and in those with higher body mass index. Both systolic and diastolic blood pressure were correlated with the derived kidney volume. However, when corrected for age, sex and BMI the relationship was not statistically significant. Blood pressure correlated inversely with the width : length ratio of the left kidney.

CONCLUSIONS

Blood pressure was not correlated with kidney size in this group of adults.

A collaborative audit of the management of hypertension in general practice

We carried out an audit of the management of essential hypertension in general practice, against standards based on current guidelines. We examined the records of 882 hypertensive subjects (on medication) in whom hypertension had been diagnosed between January 1989 and December 1993, from 14 general practices in the Portsmouth and South East Hampshire Health Authority. The overall prevalence of hypertension was 3.5%. Pretreatment blood pressure had been measured on three or more occasions in 87% of patients. Pretreatment blood pressure was equal to or greater than 150/95 mmHg in 96% and 160/100 mmHg in 86.5% of patients. A thiazide diuretic was the initial drug of choice in 30% of patients, with beta-blockers being the most popular initial treatment. Ninety per cent of patients had had their blood pressure measured at least once during the preceding year. In 82.5% of patients, current blood pressure was less than 150/95 mmHg, while 44% achieved a current blood pressure less than 140/90 mmHg. We conclude that the prevalence of hypertension in this population was lower than expected, suggesting the need for improved screening. We also propose that the initial treatment choice should be a thiazide in the majority, which would result in significant cost saving. The blood pressure control was suboptimal compared to current guidelines.

Biological assay for tissue kallikrein: comparison with the synthetic substrate S2266

A highly sensitive biological assay for tissue kallikrein is described, using human kininogen as substrate; and quantitation, by radioimmunoassay, of generated kinins. Using purified human urinary kallikrein as a reference standard we have correlated the kininogenase activity of kallikrein with amidase activity as measured by cleavage of the synthetic substrate S2266.

Association of myocarditis and acute renal failure complicating meningococcal septicaemia

We report a case of meningococcal septicaemia complicated by myocarditis, cardiogenic shock and acute renal failure. Following protracted haemodynamic support and haemodialysis, there was complete recovery of cardiac and renal function.

Bartter's syndrome and diabetes mellitus

We here report a case of Bartter's syndrome occurring in association with diabetes mellitus. The patient, an insulin-dependent diabetic, presented with hypokalaemia, inappropriate kaliuresis and metabolic alkalosis. He had high plasma renin activity, relatively low plasma aldosterone, and resistance to infused angiotensin II. A high potassium diet raised total body potassium and serum potassium, did not affect plasma renin activity, but raised plasma aldosterone significantly and did not alter the resistance to angiotensin II. Indomethacin administered acutely reduced urinary potassium and kallikrein excretion and, on chronic administration, lowered plasma renin activity, urinary chloride excretion, and raised serum potassium. Salt restriction resulted in a prompt and significant reduction in urinary sodium and chloride excretion. Urinary kallikrein excretion was very high throughout, increased with sodium restriction, and decreased with sodium loading. Oral potassium supplementation partially corrected the hypokalaemia, but did not affect blood sugar control. In this patient the primary defect appears to have been primary urinary potassium wasting, rather than sodium or chloride wasting. The striking effects of indomethacin suggest that prostaglandins may play a fundamental role in the genesis of the syndrome.

Meningococcal septicaemia presenting as erythema multiforme

A 48-year-old woman presented with a three-week history of recurrent, generalised rash, flitting joint pains, frontal headache and shivering attacks. On admission she was pyrexial and exhibited a symmetrical generalised maculopapular rash with a few target lesions. The rash faded within the first 24 hours, but over the following week it recurred at intervals of 48 hours and was accompanied by fever and headache. She was started on a short course of steroids, which did not alter her symptoms or signs. Eight days after admission, the patient underwent a lumbar puncture, despite the absence of definite signs of meningeal irritation. The cerebrospinal fluid (CSF) was turbid and diagnostic of bacterial meningitis. Cultures of blood and CSF taken on the day of admission both grew Neisseria meningitidis. The patient was successfully treated; symptoms were completely resolved.

Azathioprine and allopurinol: a potentially dangerous combination

We report the association of leucopenia and anaemia in five patients given a combination of azathioprine and allopurinol. Three subjects were renal transplant recipients with mild to moderate impairment of graft function. The complication appeared between 4 and 6 weeks following initiation of the combination therapy. Discontinuation of one of the two drugs resulted in full recovery within 4-8 weeks.

Respiratory distress during total parenteral nutrition

We report on a patient who developed fatal respiratory distress two days after starting parenteral feeding for malnutrition complicating Crohn's disease. Post mortem examination revealed pulmonary collapse secondary to mediastinal leak of the infusion fluid due to an undiagnosed erosion of the vascular catheter tip through the brachiocephalic vein.

Hyperammonaemic coma in ureterosigmoid urinary diversion

We report on a patient with ureterosigmoid anastomosis, who presented with recurrent episodes of confusion, agitation and aggressive behaviour, culminating in coma. Investigations revealed profound hyperammonaemia, which responded to treatment with sodium benzoate and sodium phenylacetate. No definite cause was found for the abnormality, apart from possible urinary tract infection. The patient remains well on a protein restricted diet with mildly elevated levels of plasma ammonia.

Rabies presenting with myocarditis and encephalitis

We report a case of rabies acquired in Zambia by a 45-year-old woman who presented with a history of an influenza-like illness, abnormal behaviour and signs of myocarditis. A provisional diagnosis of systemic viral infection was made. Within 12 h of admission the patient developed features of rabies that included hydrophobia. She was artificially paralysed and ventilated electively. Empirical antibiotic therapy was given also. Signs of myocarditis and fever disappeared within 48 h. Her clinical condition remained stable but she required heavy sedation. On the ninth day after admission the patient developed features of inappropriate secretion of antidiuretic hormone and gradually became water-logged. Intake of fluid was therefore restricted. Her level of consciousness deteriorated progressively to the point where sedation was no longer required. Brain death was diagnosed 14 days after admission.

Phaeochromocytoma presenting with cardiogenic shock and acute renal failure

A patient with a 12 hour history of headache, breathlessness and hypotension developed acute renal failure necessitating haemodialysis for 12 days. During recovery she developed hypertension, tachycardia and facial flushing. Investigations revealed a right adrenal phaeochromocytoma. Whilst postural hypotension is common in phaeochromocytoma, profound shock with acute renal failure is rare. This may have been precipitated by concomitant drug therapy, myocardial necrosis or by necrosis within the tumour.

Lactase insufficiency in Chinese children detected by oral milk and lactose challenge

A study to determine the incidence of late-onset lactose intolerance was undertaken in 68 normal Chinese children in Singapore using measurements of breath hydrogen concentrations, following a lactose or milk challenge, as indicator of lactose malabsorption. Evidence of lactose malabsorption was detected in 26% of children given a lactose challenge, and in 21% of those given a milk challenge. It is concluded that late-onset lactase insufficiency is common in Chinese children in Singapore.

Comparison of the effects of atenolol, sotalol and labetalol on muscle blood flow in man

A double-blind study of the effect of three beta-adrenoceptor blocking drugs (beta-blockers) on exercise muscle blood flow (MBF) in 14 normotensive volunteers was carried out. MBF was measured by the xenon-133 clearance technique. MBF was not altered by placebo, sotalol or labetalol. Atenolol significantly reduced MBF compared with placebo, sotalol and labetalol. We conclude that sotalol and labetalol may be more useful than conventional beta-blockers for treatment of hypertension or angina in association with peripheral vascular disease.

A blind controlled trial of phase-contrast microscopy by two observers for evaluating the source of haematuria

Two observers, unaware of each other's findings and of the diagnosis, examined red cells in the urine of 109 patients by phase-contrast microscopy. All specimens were examined uncentrifuged by inverted microscopy, and 48 of the 109 were also examined under a light microscope after centrifugation. We were unable to confirm with either method the close correlation between red-cell morphology and diagnosis reported in previous studies, and our 2 observers differed in their interpretation on 38% of occasions. Proteinuria associated with the presence of casts in uncentrifuged urine examined by inverted microscopy was a better indication than red-cell morphology of renal parenchymal disease.

Enalapril in the treatment of hypertension associated with impaired renal function

This pilot study was undertaken to examine the safety and efficacy of enalapril in the treatment of hypertension associated with impaired renal function. Forty-one patients with glomerular filtration rate (GFR) < or = 50 ml/min received enalapril for up 12 weeks. Blood pressure, renal function, biochemistry and haematology were monitored weekly for 4 weeks and then monthly. Blood pressure was effectively reduced within 4 weeks; this reduction was maintained for at least 12 weeks. Renal function remained stable and there was no significant sustained alteration in any biochemical or haematological parameter. Requirement for additional antihypertensive drugs was reduced during enalapril therapy. These data suggest that enalapril may have a useful role in the management of hypertension associated with renal impairment.

The effect of captopril on autonomic reflexes in human hypertension

The effects of acute administration of captopril on heart rate, blood pressure and physiological responses to head-up tilt, hand-grip, exercise and Valsalva manoeuvre were studied in 25 hypertensive subjects (10 untreated, 15 previously treated). After chronic administration for 8-12 weeks the effect on heart rate, blood pressure and the response to head-up tilt were studied again in 15 of these subjects. After the first dose of captopril (0.5 mg/kg), both systolic and diastolic blood pressures fell significantly, with no change in heart rate. Head-up tilting produced a significant increase in heart rate without any alteration in the blood pressure; hand-grip produced a significant increase in heart rate and blood pressure. These responses and exercise-induced tachycardia were unaltered by captopril. There was a significant reduction in the Valsalva ratio. After chronic administration the hypotensive efficacy was maintained for 10-12 h after the last dose, suggesting that twice daily dosage may be sufficient. There was a significant reduction in the basal supine heart rate by captopril. Head-up tilt produced the same physiological changes as in the acute study. These findings suggest that captopril has a vagotonic effect, possibly associated with resetting of baroceptor mechanisms. This could be one explanation for the hypotensive effect of captopril even in low-renin states.

Oral treatment of peritonitis complicating continuous ambulatory peritoneal dialysis

The efficacy of oral treatment with cephradine in peritonitis associated with continuous ambulatory peritoneal dialysis (CAPD) was compared with that of intraperitoneal cefuroxime over one year. There were 29 episodes of peritonitis in each group and a primary cure was achieved in 66% of the patients treated with cephradine compared with 55% of the patients treated with cefuroxime, suggesting that oral cephradine is as effective as a treatment with intraperitoneal cefuroxime. Nineteen of the 29 episodes in each treatment group were considered suitable for out-patient management and there was no difference in the success rate of either antibiotic regimen. The results suggest that out-patient treatment with oral cephradine is an efficient way of treating CAPD peritonitis.

Loa loa: the use of a blood cell separator to reduce microfilaraemia before specific chemotherapy

Three years after returning to the U.K. a 58-year-old British engineer, who had worked in the Nigerian oilfields for 24 years, was found to have Loa loa. His midday microfilarial count ranged between 12 X 10(6) and 16 X 10(6) parasites per litre. Before starting treatment, I litre of leucocyte/platelet-rich plasma was removed by means of a blood cell separator. Six intermittent cycles of blood separation were performed during a single 4-h session around midday in order to coincide with the period of maximum microfilarial presence in the peripheral circulation. This resulted in a 50% reduction of the microfilaraemia. Where facilities for blood cell separation are available, this procedure, together with appropriate chemotherapy, should be particularly beneficial in the management of heavy filarial infections.