Survival analysis of Thai patients with IgM nephropathy, focal segmental glomerulosclerosis and membranous nephrotic syndrome.

Long term outcome of 124 Thai adult nephrotic patients was determined. Nephrotic syndrome affects the young more often than the old (median age 29 years). The most common pathology was IgM nephropathy (45.2%), membranous nephropathy (31.5%) and FSGS (23.4%). Sixty-four per cent of patients with IgM nephropathy respond to corticosteroid within 4-8 weeks while twenty three per cent were late responders. However, more than half of these patients were relapsers or steroid dependent. Response to corticosteroid occurred in 48.2 per cent of patients with FSGS while the response rate of patients with membranous nephropathy was only 23.1 per cent. Survival analysis revealed that five and ten years renal survival of IgM nephropathy was 98 per cent. Five and ten years renal survival of FSGS was 83.7 per cent and 76.8 per cent while those of membranous nephropathy was 95 per cent and 63.3 per cent. The response to corticosteroid was associated with better prognosis in FSGS. Our results show that patients with IgM nephropathy and membranous nephropathy have a generally good prognosis. Renal function is usually well preserved for at least ten years. The prognosis of patients with FSGS varied and correlated with the degree of steroid responsiveness.

Antineutrophil cytoplasmic antibody (ANCA) and rapidly progressive crescentic glomerulonephritis in Thai population.

The impact of vasculitis as a cause of primary rapidly progressive crescentic glomerulonephritis (RPGN) was examined in patients with Thai ethnic by antineutrophil cytoplasmic antibody (ANCA) test. Thirty patients found in a six years study period were included. Patients' mean age was 34.8+/-16.4 years. Mean crescent score was 86.2+/-22.9%. ANCA proved positive in fifteen patients. This helps to differentiate vasculitis associated (ANCA positive) from nonvasculitis (ANCA negative) RPGN. Incidence of immune complex type RPGN (46.6%) is higher than the Caucasians while the incidence of antiglomerular basement membrane antibody (anti-GBM disease) is much lower. More vasculitis patients were treated with cyclophosphamide (n = 11) than the nonvasculitis group (n = 2). Mean renal survival time of ANCA and non-ANCA associated patients were 26.69 and 14.16 months, respectively. Renal survival of all patients is significantly worse if associated with a high entry creatinine (>6 mg/dl). Our results show that vasculitis associated RPGN is not an uncommon disease in the Thai population and can be recognized initially by ANCA test.

Heterogeneity of antibody response to glomerular basement membrane antigen in patients with different forms of glomerulonephritis.

Antibodies to collagenous and noncollagenous components of glomerular basement membrane (GBM) have been detected by immunoblotting in some sera from patients with various kinds of glomerulonephritis. A half proportion of patients with rapidly progressive glomerulonephritis (RPGN), chronic focal glomerulonephritis (CFGN), idiopathic membranous glomerulonephritis (MGN). IgA nephropathy and lupus nephritis (LE-GN) had IgG antibodies to heterogenous components in acid insoluble fraction of pepsin digested GBM. This acid insoluble fraction represented a complex of collagen and noncollagenous proteins of GBM. Following digestion of acid insoluble fraction with bacterial collagenase, the triple helical collagenous components of GBM were destroyed and released most likely of noncollagenous proteins. Antibodies to this noncollagenous proteins were found in only some patients with chronic glomerulonephritis (17.6%) and lupus nephritis (21.4%). Upon reaction with human placenta derived type IV collagen, different frequencies of antibody response were found in patients of different groups. However, all these reactive sera showed a similar immunoblotting pattern. The relationship between antibody response to antigenic components from human GBM or human placenta and pathogenesis of renal disease is unclear. However, the occurrence of spontaneous autoantibody response to some exposed GBM self antigens may mediate further renal destruction resulting in chronic ongoing stage of the disease.