Overview
Definition
The most common primary glomerulonephritis worldwide, characterized by the deposition of IgA immune complexes in the glomerular mesangium.
Epidemiology
Most common in young males (teens/20s) of East Asian and Caucasian descent.
Etiology & Risk Factors
- Deposition of galactose-deficient IgA1 immune complexes in the mesangium, triggering inflammatory injury
- Often triggered by mucosal infections (URI or GI tract)
Clinical Symptoms
- Recurrent episodes of gross hematuria ('cola-colored urine') coinciding with or within 1-2 days of an upper respiratory infection ('synpharyngitic hematuria')
- Flank pain during hematuria episodes
Clinical Approach
Diagnosis
- Renal Biopsy (definitive) showing mesangial hypercellularity on LM, and granular IgA and C3 deposition in the mesangium on IF
Management
- ACE inhibitors or ARBs (first-line to target proteinuria < 1g/day)
- Systemic corticosteroids for patients at high risk of progression despite supportive care
- SGLT2 inhibitors
Complications
- End-stage renal disease (in 20-40% of cases over 20 years)
- Chronic hypertension
- Accelerated cardiovascular disease