Triamterene-induced crystalluria and cylinduria: clinical and experimental studies

We examined the occurrence of crystals and casts in the urine of healthy subjects after administration of triamterene and the site of crystal formation in experimental animals. Twenty out of twenty healthy subjects had abundant triamterene crystals and casts in acid urine after receiving a single 100 mg dose. Casts were present in the urine from 2-11 hours after administration of the diuretic. Cast formation occurred in acidic urine and was prevented by alkalinization of the urine with potassium citrate. Animal studies showed that crystallization and cast formation occurred in the medullary and papillary collecting ducts of the rat kidney. These findings provide a possible explanation for the reported nephrotoxicity of triamterene, particularly when given to patients who are receiving non-steroidal anti-inflammatory agents.     

IgA glomerulonephritis and pregnancy

One hundred and sixteen pregnancies in 70 women with a biopsy-proven diagnosis of IgA glomerulonephritis have been analysed. Thirty percent (35) of the fetuses died, 22% (26) were premature and 44% (52) were full term. Maternal renal function declined during pregnancy in 26% (30) and in 2% (2) this was irreversible post-partum. Hypertension developed in 52% (61) of the pregnancies and in 13% (15) this was irreversible. Increased proteinuria was recorded in 62% (74) of the pregnancies. Fetal loss in pregnancies taking place after biopsy diagnosis was lower (16%) than those in which biopsy was performed either during or following the pregnancy (36%).     

Pulmonary tuberculosis in Gurkhas in Hong Kong in the period 1984-1987 and the role played by routine radiology in case detection

A retrospective study of all cases of pulmonary tuberculosis in Gurkha soldiers and their dependants in Hong Kong in the years 1984-1987 inclusive was performed. In addition all chest X-rays requested for routine purposes and taken at the British Military Hospital, Hong Kong during 1986 were analysed. These studies showed that the current regulations requiring an annual chest X-ray for all Gurkha soldiers and their dependants were neither cost effective nor productive in screening for active pulmonary tuberculosis.     

Effect of pregnancy on moderate renal failure in reflux nephropathy

During a 10 year study of women with reflux nephropathy 20 women had plasma creatinine concentrations in the range 0.2-0.4 mmol/l (2.3-4.5 mg/100 ml). Six experienced pregnancies exceeding 12 weeks' gestation. Pregnancy was associated with rapid deterioration in function in all six, resulting in end stage renal failure in four women within two years after delivery despite adequate control of blood pressure. Of the 14 women who did not have a prolonged pregnancy, four had periods of uncontrolled hypertension, all of which were related to non-compliance or loss from follow up, or both. Uncontrolled hypertension was also associated with accelerated renal failure, and all four women progressed quickly to end stage renal failure. The remaining 10 women were observed for from five to 10 years; in all 10 renal function deteriorated slowly, and none reached end stage renal failure within seven years. It is concluded that pregnancy in patients with reflux nephropathy and moderately severe renal failure has a deleterious effect on renal function.     

Use of esmolol in a parturient with hypertrophic obstructive cardiomyopathy

The physiological changes occurring during pregnancy and labour may reveal or exacerbate the symptoms of hypertrophic obstructive cardiomyopathy (HOCM). We describe the management of labour in a patient with severe HOCM during which esmolol, a short-acting beta adrenergic antagonist, was used together with extradural analgesia and invasive cardiovascular monitoring to achieve an assisted vaginal delivery with minimal haemodynamic disturbance. The effects on the infant are described and the literature on the use of esmolol in pregnancy is reviewed.      

Poor results of KTP Laser tonsillectomy compared with conventional dissection: a prospective clinical trial

The aim of this study was to compare the clinical outcome of KTP Laser tonsillectomy with conventional dissection tonsillectomy. Seventy-four Laser tonsillectomy patients (mean age 14 years, range 2–91 years) were compared prospectively with 157 conventional dissection tonsillectomy patients (mean age 18 years, range 2–71 years). KTP Laser tonsillectomy was performed using 0.6 fibre optic cable at 10 Watts continuous. Conventional dissection tonsillectomy was by standard techniques. Operating time, intra-operative bleeding, postoperative pain at 1, 7 and 14 days, incidence of delayed healing, postoperative bleeding and hospital readmission were compared. There was no significant difference in operating time between Laser and conventional tonsillectomy. At days 1, 7 and 15 the Laser group reported significantly higher pain scores than the conventional group (P < 0.0001, Mann–Whitney U test) and showed evidence of delayed healing at 14 days (P < 0.0001, χ² test). The Laser group had less intra-operative bleeding (P < 0.02) but this effect disappeared when the confounding effect of age was controlled by analysing children under 12 separately. KTP Laser tonsillectomy results in significantly more postoperative pain and delayed healing compared with conventional dissection tonsillectomy. It is no quicker than conventional dissection tonsillectomy. Blood loss was less in the Laser group but this may be accounted for by younger age. KTP Laser should not replace conventional tonsillectomy as standard technique. It may have a limited role where minimizing intra-operative blood loss is an overriding consideration.     

An outbreak of cryptosporidiosis in an urban swimming pool: why are such outbreaks difficult to detect?

OBJECTIVE: To describe an outbreak of Cryptosporidium gastroenteritis in a swimming pool in Melbourne in early 1998 that was not detected through routine surveillance, and discuss difficulties in identifying such outbreaks. METHODS: The Water Quality Study (WQS) was a large community-based study of gastroenteritis. Following suspicion of an outbreak of cryptosporidiosis within the study group, due to pool "X", a nested case control study was performed. Each case of Cryptosporidium gastroenteritis was matched with six controls and data from weekly Health Diaries from the WQS were reviewed. The Department of Human Services also instigated active surveillance among patrons at pool "X" using a systematic sample of 50 people from the pool's swim-school enrollment list. RESULTS: There were seven cases of Cryptosporidium gastroenteritis in the case control study. Five cases and eight controls swam at pool "X" during the outbreak period. The adjusted odds of developing cryptosporidial diarrhoea if an individual swam at pool "X" was 34.5 (CI 2.3-2548). DHS identified another 11 laboratory confirmed cases associated with pool "X" as well as cases not linked to pool "X". 125 cases were identified throughout Melbourne with the suspected involvement of seven swimming pools. CONCLUSIONS: Despite a high odds ratio of developing cryptosporidiosis this outbreak was not detected by routine surveillance methods. Current outbreak detection methods lack sensitivity, specificity or timeliness. IMPLICATIONS: Improved surveillance systems are required if outbreaks of gastroenteritis are to be detected early so an intervention can be instigated to reduce the amount of subsequent illness.