Can Varicella Cause Post-Infectious Glomerulonephritis (PIGN)?
Yes, varicella can cause PIGN, though it is an extremely rare complication. While Group A Streptococcus remains the most common causative agent of PIGN in children, varicella-zoster virus has been documented as a rare infectious trigger for acute glomerulonephritis 1, 2.
Evidence for Varicella-Associated Glomerulonephritis
The association between varicella and glomerulonephritis is well-documented but uncommon:
- Case reports demonstrate that varicella can trigger membranoproliferative glomerulonephritis with massive proteinuria (up to 16 g/24 hours), gross hematuria, and pyuria 1
- Most reported cases of post-varicella glomerulonephritis occur in children, though adolescent cases have been documented 1
- The mechanism appears to be immune complex-mediated hypocomplementemic glomerulonephritis in response to varicella-zoster infection 1
Clinical Context and Epidemiology
Understanding the broader landscape of PIGN helps contextualize varicella as a cause:
- Non-streptococcal organisms are emerging as important etiological agents of PIGN in high-income countries, expanding beyond the traditional post-streptococcal paradigm 2
- The spectrum of causative agents for PIGN includes multiple viral and bacterial infections beyond Group A Streptococcus 3
- Staphylococcal infections are now as common as streptococcal infections in causing PIGN, particularly in adults 4
Clinical Presentation and Prognosis
When varicella does cause glomerulonephritis, the clinical features are important to recognize:
- Proteinuria in most post-varicella glomerulonephritis cases is benign and self-limiting, though rare fatal cases of crescentic glomerulonephritis progressing to acute renal failure have been reported 1
- The clinical presentation can vary from asymptomatic microscopic hematuria to rapidly progressive glomerulonephritis requiring dialysis 3
- Acute proliferative glomerulonephritis typically manifests as immune complex hypocomplementemic disease 1
Important Caveats
Several clinical pitfalls warrant attention:
- The rarity of this complication means varicella should not be the first suspected cause when evaluating PIGN - streptococcal and staphylococcal infections remain far more common 2, 5
- Renal involvement during varicella infection is infrequent overall, making this an unusual presentation 1
- The latency period between infection and nephritis onset (characteristic of PIGN) should be considered when establishing temporal relationships 5
Practical Implications
For immunocompromised patients with nephrotic syndrome who develop varicella:
- High-dose intravenous acyclovir (10 mg/kg every 8 hours) for 7-10 days is mandatory for treatment 6
- Post-exposure prophylaxis with varicella-zoster immune globulin (VZIG) should be administered as soon as possible after exposure, effective up to 10 days post-exposure 6
- If VZIG is unavailable, prophylactic oral acyclovir (10 mg/kg four times daily for 7 days) within 7-10 days of exposure is recommended 7, 6