Comparison of progression of renal failure in children with hypoplastic-dysplastic kidneys and chronic glomerulonephritis.

A comparative study was made on two groups of children comprising 20 patients with renal hypoplasia/dysplasia in one group and 12 patients with chronic glomerulonephritis (GN) in the other, presenting with chronic renal failure (CRF) in the Department of Paediatrics, Singapore General Hospital and National University Hospital between 1975 and 1989. The age of onset of CRF, the progression of renal failure and the presence of various clinical complications were analysed and compared. The mean age of onset of CRF was earlier in patients with renal hypoplasia/dysplasia (p less than 0.001) but the progression of renal failure in these patients were slower (p less than 0.005). Hypertension occurred more frequently in the chronic GN group (p less than 0.001) while urinary tract infection (UTI) occurred more frequently in the renal hypoplasia/dysplasia group (p less than 0.004). With the early onset of renal failure and slow deterioration of renal function in patients with renal hypoplasia/dysplasia, the provision of good conservative treatment for renal failure is most important in the management of these patients. In the chronic GN patients however, with the rapidity of deterioration of renal function, early preparation for replacement therapy becomes more imminent. However, renal replacement therapy in end-stage renal failure (ESRF) is costly and not readily available, it is more prudent to delay the onset of ESRF by providing effective conservative treatment of renal failure which includes the early recognition and treatment of hypertension in chronic GN and UTI in renal hypoplasia/dysplasia.

Vesicoureteric reflux and renal scarring in children--a local perspective.

This study was undertaken to determine the extent of primary vesicoureteric reflux and renal scarring in patients investigated for urinary tract infection in the Singapore General Hospital between 1983 and 1988. The clinical profile of patients and possible clinical features associated with renal scarring were analysed. These findings serve as a useful guide in the investigation and management of VUR in our population. The incidence of vesicoureteric reflux among patients investigated for documented urinary tract infection was high at 32.9%. The mean age at presentation was 15.2 months. Almost all patients were less than five years-old. A male predominance was noted in affected infants. High grade refluxes of Grade IV or more (International Reflux Study Classification) were found in 45.7/patients and were associated with a higher incidence of recurrent urinary tract infection (p less than 0.05). Thirty-four 99mTc-dimercaptosuccinic acid scans were done and 46.4% of refluxing kidneys showed renal scars. The incidence of renal scarring was significantly higher in patients presenting at an early age (less than 2 years), in high grade reflux and in recurrent urinary tract infection (p less than 0.05; p less than 0.01 and p less than 0.001 respectively). Therefore all children with documented urinary tract infection who are less than five years old and especially male infants should be fully investigated for early detection and treatment of vesicoureteric reflux and renal scars. Kidneys with vesicoureteric reflux at risk of scarring appeared to be those with early presentation, high grade reflux and recurrent urinary tract infection whose management should therefore be vigorous.

Acute glomerulonephritis--changing patterns in Singapore children.

This study compared the pattern of acute glomerulonephritis (AGN), a disease known to be influenced by socioeconomic and environmental factors, in children 12 years and under, for the years 1971 and 1985. All children admitted to the four major paediatric departments with haematuria and at least two of the following (oedema, hypertension or oliguria) had an initial diagnosis of AGN. A sample population from one unit from 1980 to 1984 showed that over 70% of these children had evidence of a post-streptococcal aetiology. In 1971, 411 children were admitted with AGN, as compared with only 58 in 1985. The age-sex-race standardized rates for 1971 and 1985 were 0.632 and 0.023/1,000 children 12 years and under, respectively (P less than 0.001). The mean age of presentation was lower in 1971. Over this period, Singapore saw a threefold rise in the gross national product, accompanied by rapid urbanization. On analysis of the housing pattern, only 31% of the children lived in high-rise apartments in 1971, in contrast with 86% in 1985 (P less than 0.001). The majority of non-apartment dwellers had homes in rural districts. From an epidemiological perspective, factors which could have led to the highly significant decline in prevalence of AGN in Singapore children included improvement in the socioeconomic status and health care system, and urbanization of the country.

Management of urinary tract infection and vesico-ureteric reflux in children.

Even though urinary tract infection is common in childhood, its diagnosis and management can be difficult. One must be aware of factors that may interfere with urine culture result. Besides urinary stasis, renal tract abnormalities and detrusor instability, host factors and certain strains of invading organisms (P-fimbriated E Coli) may be important in the pathogenesis of urinary trace infection. The choice of antibiotics for treatment of urinary tract infection should be guided by the age of the patient, clinical presentation and urine culture result. The management of vesico-ureteric reflux depends on its grading. Grade I and II can be treated medically by long-term low dose antibiotics because spontaneous resolution is high. For Grade III and IV, the treatment of choice is controversial. Controlled prospective studies showed that surgical reimplantation did not prevent new scar formation, progression of old scars and breakthrough infection. Endoscopic submeteric injection of Teflon is a new method to correct vesico-ureteric reflux. Despite favourable short-term results, the long-term outcome is unknown.

Febrile convulsion--a clinical survey and a review of its current concept of management.

Between February 1986 to November 1986, 335 cases of febrile convulsion were admitted to the paediatric ward, Tan Tock Seng Hospital. The study revealed 87 cases (26%) were complex febrile convulsion and 73 cases (21.8%) were recurrent febrile convulsion. 51 patients with complex febrile convulsion and 32 patients with recurrent febrile seizures were put on long term phenobarbitone. The number of patients with recurrent and complex convulsion was big. The role of anticonvulsant prophylaxis is reviewed and its efficacy discussed.

Pattern of glomerulonephritis in Singapore children--a renal biopsy perspective.

This study was aimed at determining the pattern of glomerulonephritis (GN) in Singapore children from a histopathological perspective. Fifty-seven consecutive children, aged between 10 weeks to 16 years, who underwent a renal biopsy at the Departments of Paediatrics, National University of Singapore and Singapore General Hospital over an 8 year period were studied. The main indications for biopsy were nephrotic syndrome (67%), recurrent gross haematuria (16%), nephritic syndrome (7%), and renal failure (10%). Primary GN occurred in 81%, while secondary GN was seen in 19%, the most common being lupus nephritis. Of the primary GN, minor abnormalities was the most common (22%), followed by focal global sclerosis (20%), focal segmental glomerulosclerosis (17%), diffuse mesangial proliferative GN (11%), focal mesangial proliferative GN (9%), membranous GN (7%), diffuse endocapillary GN (4%), diffuse sclerosing GN (4%), diffuse mesangial sclerosis (4%), and diffuse crescentic GN (2%). Immunofluorescent examination was performed in 50 children. IgA nephropathy was diagnosed in 17% of the patients with primary GN. Of the children with primary nephrotic syndrome due to minimal change disease or focal global sclerosis, about half had IgM mesangial deposits. Of 47 patients who were followed up, 9 developed chronic renal failure, of which 7 reached end-stage disease (4 have died, while 3 are on chronic dialysis). Three other patients died of other complications. The histopathological findings influenced the therapeutic decision in 49% of our patients. In summary, the pattern of GN in our cohort of patients tended to reflect more severe glomerular lesions, mainly due to our criteria of selection for renal biopsy.

A 10 year review of systemic lupus erythematosus in Singapore children.

A 10 year retrospective analysis of the clinical features and survival of 24 Singapore children with systemic lupus erythematosus was made. The female to male sex ratio was 11:1. The median age at diagnosis was 9.3 years (range: 3.5-17.6 years), and the median duration of follow-up was 3.6 years (range: 3 months-10 years). The common modes of presentation were prolonged fever and malar rash (both 46%). Renal involvement (71%) was frequent. There were six deaths, three from chronic renal failure, two from infection, and one from carditis. The overall survival at 5 years was 0.800 (s.e.m. = 0.090), and at 10 years 0.698 (s.e.m. = 0.103). The survival for lupus nephritis was 0.727 at 5 years (s.e.m. = 0.116), and 0.586 at 10 years (s.e.m. = 0.130). Although the 5 year survival rate is comparable with other series, there were more deaths after the first 5 years, and morbidity from the disease as well as from therapy was considerable.

Estimation of glomerular filtration rate in children using 99m-technetium DTPA. A comparison with 51-chromium EDTA clearance.

The usefulness of radionuclide imaging studies with 99m-technetium diethylenetriaminepentaacetic acid (Tc-DTPA) for quantitating the glomerular filtration rate (GFR) in children was studied. This was compared to the conventional methods for measuring GFR using 51-chromium-EDTA clearance (Cr-EDTA), creatinine clearance and a height/plasma creatinine formula. In the 22 children studied, the correlation coefficient between renal uptake of DTPA and Cr-EDTA was 0.90 (p less than 0.001). In contrast, there was a poorer correlation between Cr-EDTA and creatinine clearance (r = 0.69) or the derived GFR using height/creatinine formula (r = 0.83). The regression line between Tc-DTPA uptake and Cr-EDTA clearance was used to derive a formula for calculating the predicted GFR. This was tested in 10 additional children, and the correlation between the predicted GFR and measured GFR (using Cr-EDTA clearance studies) was 0.92 (p less than 0.001). Quantitative estimation of the GFR during renal imaging studies is a feasible and convenient method of assessing renal function.