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This review of 2,586 renal biopsies over the past 3 decades in Singapore documents the changing pattern of glomerulonephritis (GN) from that of a third world country to that of a developed nation. In the 1st decade, mesangial proliferative glomerulonephritis was the most common form of primary GN, just as it was in the surrounding Asian countries. In the 2nd decade, the prevalence of mesangial proliferative GN decreased with a rise in membranous, GN which is also seen in China and Thailand. In the 3rd decade, there was a dramatic increase in focal sclerosing glomerulosclerosis. This increase reflects aging and obesity in keeping with more developed countries like Australia, India, Thailand and the United States of America. IgA nephritis remains the most common GN. Apart from the geographical influence, other socioeconomic factors play a significant role in the evolution of the renal biopsy pattern. Mesangial proliferative GN remains prevalent in many Asian countries, but in Singapore the prevalence is decreasing just as it is in Japan, Korea and Malaysia. Worldwide, the prevalence of focal sclerosing glomerulosclerosis continues to increase in many countries.

Objective: The prevalence of primary glomerulonephritis in Singapore is compared with that of 28 other countries to review changing trends in the evolution of primary glomerulonephritis in Asia and other countries., Method: 2,586 renal biopsies in Singapore over the past 3 decades were reviewed and compared with data from 28 other countries., Results: In the 1st decade most Asian countries have mesangial proliferative glomerulonephritis as the most common form of primary glomerulonephritis, and in the 3rd decade there has been a dramatic increase in focal and segmental glomerulosclerosis reflecting aging and obesity in keeping with more developed countries. IgA nephritis remains the commonest glomerulonephritis in many countries. Membranous glomerulonephritis continues to be more prevalent in Western countries while mesangial proliferative glomerulonephritis remains prevalent in many Asian countries., Conclusion: Apart from geographical and genetic influences, socioeconomic factors may play a role in the evolution of the biopsy pattern in some countries. Worldwide, the prevalence of focal segmental glomerulosclerosis continues to increase. In third world countries some of the commoner forms of glomerulonephritis are related to infections, in contrast to developed countries where the antigenic exposure may be related to diet, allergens and other industrial agents., (Copyright © 2010 S. Karger AG, Basel.)

Acute post-streptococcal glomerulonephritis (PSGN) is characterized by an abrupt onset of edema, hypertension, and hematuria. Life-threatening diffuse alveolar hemorrhage (DAH) is rarely associated with acute PSGN. There have been only two reported cases worldwide, and no case has been reported previously in Korea. Here, we present a patient who clinically presented with pulmonary-renal syndrome; the renal histology revealed post-infectious glomerulonephritis of immune complex origin. A 59-yr-old woman was admitted with oliguria and hemoptysis two weeks after pharyngitis. Renal insufficiency rapidly progressed, and respiratory distress developed. Chest radiography showed acute progressive bilateral pulmonary infiltrates. The clinical presentation suggested DAH with PSGN. Three days after treatment with high-dose steroids, the respiratory distress and pulmonary infiltrates resolved. Electron microscopy of a renal biopsy specimen sample revealed diffuse proliferative glomerulonephritis with characteristic subendothelial deposits of immune complex (''hump''). The renal function of the patient was restored, and the serum creatinine level was normalized after treatment.

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.

The glomerular lesions of 90 patients with asymptomatic glomerulonephritis and proteinuria of more than 1.0 gm per day were compared with 8.3 similar patients with less than 1.0 gm proteinuria. 68% of those patients with more than Igm proteinuria had glomerular sclerosis compared to 19% of those with less than Igm proteinuria (p less than 0.001). Immunofluorescence studies revealed that 77% of patients studied had IgA deposits in the mesangial region. There was no correlation between the degree of microscopic haematuria and the severity of glomerular lesions. Patients with more than 1 gm proteinuria also had significantly higher incidence of granular casts (p less than 0.001) and the presence of casts was also significantly associated with the finding of glomerular sclerosis (p 0.005). The data suggest that 1 gm proteinuria is a useful predictive index of glomerular sclerosis in patients with asymptomatic urinary abnormalities.

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.

This study measured plasma beta 2-microglobulin (beta 2-m) in patients with mesangial IgA nephritis. Plasma beta 2-m was measured in 51 patients with IgA mesangial nephritis and in 50 normal controls using a Phadebas beta 2-m RIA kit available from Pharmacia Diagnostics (Uppsala, Sweden). The mean plasma beta 2-m in IgA nephritic patients (1.92 +/- 0.67 mg/l) was significantly different from that of healthy controls (1.33 +/- 0.41 mg/l; p less than 0.001). The mean plasma beta 2-m in non-IgA nephritic patients (1.83 +/- 0.73 mg/l) was also significantly different (p less than 0.001). Patients with IgA nephritis with glomerular sclerosis (n = 33) had significantly higher levels of beta 2-m (2.02 +/- 0.70 mg/l) than IgA nephritic patients without glomerular sclerosis (n = 18, 1.72 +/- 0.65 mg/l; p less than 0.025). In the group with IgA nephritis and glomerulosclerosis, raised beta 2-m levels were correlated with the severity of proteinuria (r = 0.41) (p less than 0.02) as well as the intensity of IgA staining on immunofluorescence (r = 0.34; p less than 0.05). Elevated beta 2-m levels in IgA nephritis may serve as a useful prognostic marker.

The pattern of glomerulonephritis (GN) consisting of 1057 renal biopsies is presented. Primary GN accounted for 91% and secondary GN 9% of which the commonest is lupus nephritis. Asymptomatic haematuria and proteinuria was the commonest mode of presentation (41%), gross haematuria 9%, nephrotic syndrome 29% while 5.5% presented with renal impairment and 4.3% with hypertension. Mesangial proliferative GN is the commonest histopathological lesion forming 66% of all primary GN. Minimal Lesion, Focal Global Sclerosis and Focal Segmental Glomerulosclerosis accounted for 7% each. Membranous GN was uncommon (3%) while Mesangiocapillary GN, Diffuse Endocapillary GN and Crescentic GN were even rarer. If the presenting feature was asymptomatic haematuria and proteinuria the likely diagnosis was IgA nephritis, and, if nephrotic syndrome it was likely to be Idiopathic Mesangial Proliferative GN but with negative staining on immunofluorescence. The course and prognosis of the various forms of GN are next discussed. Nephrotic syndrome with Minimal Lesion has an excellent prognosis while Crescenteric GN usually carries a grim prognosis. Finally, factors affecting the progression of IgA nephritis, the commonest form of GN occurring in Singapore are examined. Patients who developed renal failure ran two different courses; one was a slowly progressive course over an average of 7.7 years before reaching end stage renal failure (ESRF), while the other was a more rapid decline to ESRF within an average of 3.3 years where severe uncontrolled hypertension seemed to be the major adverse factor. 9% had renal impairment at the end of a follow up of 50 + 1/2 - 34 months while 5% progressed to ESRF. The cumulative renal survival was 91% after 6 years with no further loss up to 14 years. Unfavourable long term prognostic indices were proteinuria of more than 2 gms, hypertension, crescents on renal biopsy, severe segmental sclerosis and medial hypertrophy of blood vessels.

The protein selectivity index was measured in 68 patients (53 males, 15 females) with proteinuria due to IgA nephropathy to determine whether it bore any relationship to other clinical and pathological features of known prognostic significance. The mean age of the patients was 25 +/- 8 years with a follow-up period of 42 +/- 35 months. Forty-six presented with asymptomatic haematuria and proteinuria, 17 with macroscopic haematuria and 5 with the nephrotic syndrome. Twenty-three (34%) patients had selective proteinuria and 45 (66%) had non-selective proteinuria. Patients with non-selective proteinuria had more glomerulosclerosis (29% +/- 20 vs. 16% +/- 20, p less than 0.02), higher serum creatinine (1.47 mg/dl +/- 0.70 vs. 1.17 mg/dl +/- 0.33, p less than 0.02), lower creatinine clearance (79 ml/min +/- 28 vs. 95 ml/min +/- 25, p less than 0.02), and higher incidence of hypertension (chi 2 = 3.84, p less than 0.05) when compared to those with selective proteinuria. The protein selectivity was measured at the end of the study. Of the 5 patients with the nephrotic syndrome, 1 had poorly selective proteinuria and failed to remit and 4 had highly selective proteinuria who either remitted spontaneously (1 patient) or with treatment (3 patients). The results suggest that patients with IgA nephropathy and poorly selective proteinuria are more likely to have other features indicating a poor prognosis such as glomerulosclerosis, renal impairment and hypertension.

Fifty-two pairs of patients with idiopathic diffuse mesangial proliferative glomerulonephritis entered a controlled 3-year prospective trial of a combination regimen of cyclophosphamide, dipyridamole and warfarin. In the treatment group proteinuria decreased significantly (p less than 0.01) and renal function remained stable, but in the control group there was no change in proteinuria and creatinine clearance (Ccr) decreased significantly (p less than 0.01). The time patients with renal impairment in the control group and those in the treatment group took to reach end stage renal failure was significantly different (6.1 years versus 8.9 years, p less than 0.02). Among the patients with IgA nephritis, those in the treatment group (n = 27) had stable renal function and a significant decrease in proteinuria (p less than 0.01) but in the control group (n = 21) there was a significant fall in Ccr (p less than 0.01) and rise in serum creatinine (p less than 0.02) with no change in proteinuria. Among 23 pairs of patients in the study who were matched for renal function and degree of glomerulosclerosis, those in the treatment group had stable renal function and decrease in proteinuria (p less than 0.01) whereas those in the control group had decreased Ccr (p less than 0.01) but no change in proteinuria.