We reported 10 patients with
IgA-dominant PIGN encountered at a single center, each characterized by subepithelial humps. Their demographic, clinical, and renal biopsy findings were summarized and compared with the data of 32 patients with non-
IgA-dominant PIGN.
RESULTS: The mean age was 57 years. An immunocompromised background was present in 70% of patients; only one patient had
diabetes mellitus. The causative infectious agents included Staphylococcus (30%), Streptococcus (20%), and gram-negative organisms (50%). Decreased serum
complement was present in 60%. Increased serum
IgA was noted in 75%. The mean peak serum
creatinine was 5.1 mg/dL, and 20% required acute dialysis. Diffuse endocapillary-proliferative
glomerulonephritis was found in all cases, and three patients also had crescentic
glomerulonephritis. Electron microscopy revealed large subepithelial hump-shaped deposits in all cases. At the last follow-up, one patient had died, five had achieved complete recovery, three had persistent
renal insufficiency, and one was on chronic dialysis. Compared to patients with non-
IgA-dominant PIGN, increased serum
IgA was more commonly present in
IgA-dominant group (p = 0.007). There were no significant differences in other clinical parameters and outcome between the two groups.
CONCLUSIONS:
IgA-dominant PIGN resembles poststreptococcal
glomerulonephritis in its histological spectrum and ultrastructural appearance. Increasing serum
IgA may be involved in the pathogenesis of this form of PIGN. Our data suggested that
IgA-dominant PIGN was not peculiar to
staphylococcal infection and diabetic patients.