Korean J Pathol.  2012 Apr;46(2):105-114.

Clinicopathologic Features of IgA-Dominant Postinfectious Glomerulonephritis

• Koo TY
• Kim GH
• Park MH

Abstract

BACKGROUND
IgA-dominant acute postinfectious glomerulonephritis (APIGN) is a recently recognized morphologic variant of APIGN, but its clinicopathologic features were not clearly characterized. We will present demographic, clinical and renal biopsy findings from seven patients with IgA-dominant APIGN with a literature review.
METHODS
All renal biopsy specimens (n=1,119) processed by the Department of Pathology in Hanyang University Hospital from 2005 to 2009 were reviewed. Seven patients with IgA-dominant APIGN were identified, and their clinical data analyzed.
RESULTS
All patients had renal failure, hematuria and proteinuria. One was diabetic, and none of the patients had previous renal diseases. Three had clinical infections at the time of presentation: 2 with methicillin-resistant Staphylococcus aureus and one with rickettsial infection. Light microscopically diffuse endocapillary proliferative and exudative glomerulonephritis was found in all cases. Immunofluorescence microscopy showed granular IgA deposits along peripheral capillary walls and in mesangium. Ultrastructurally, subepithelial 'humps' with mesangial deposits were noted. End-stage renal disease developed in two patients, chronic renal failure was stationary in two, and azotemia improved in three.
CONCLUSIONS
Various infections including rickettsiosis preceded IgA-dominant APIGN in both diabetics and nondiabetics. Because the prognosis of IgA-dominant APIGN is poor, early diagnosis based on renal biopsy is required.

Keyword

Postinfectious glomerulonephritis; Immunoglobulin A; Renal biopsy

MeSH Terms

Azotemia
Biopsy
Capillaries
Early Diagnosis
Glomerulonephritis
Hematuria
Humans
Immunoglobulin A
Kidney Failure, Chronic
Light
Methicillin-Resistant Staphylococcus aureus
Microscopy, Fluorescence
Prognosis
Proteinuria
Renal Insufficiency
Immunoglobulin A