POST INFECTIOUS GN

SUMMARY

1. Usually caused by group A beta-hemolytic streptococcal infections of the skin or throat.

2. Symptoms include gross hematuria and/or edema and occur 1-6 weeks after the initial illness (average 10 days post-throat infections, 2-4 weeks after skin infections).

3. Antistreptococcal antibodies aid in the diagnosis: Anti-streptolysin O (ASO) titer, Anti-deoxyribonuclease B (anti-DNase B) titer, Anti-hyaluronidase titer.

4. PIGN is caused by an antibody-antigen reaction.

5. Renal biopsy shows immune deposits (IgG, lgM, and complement) in the subendothelial and subepithelial regions (termed "humps") + invasion of the glomerulus with neutrophils.

6. Summary of PIGN: reversible, bloody urine remote to group A streptococcal skin or throat infection (rarely, other infections); low complement for 6-8 weeks; variably positive antistreptococcal antibody titers; subendothelial and subepithelial immune "humps" on renal biopsy; treat the infection; good response in most.

Reference(s)

Wilkinson, I., Furmedge, D. and Sinharay, R. (2017). Oxford handbook of clinical medicine. Oxford: Oxford University Press. Get it on Amazon.
Feather, A., Randall, D. and Waterhouse, M. (2020). Kumar And Clark’s Clinical Medicine. 10th ed. S.L.: Elsevier Health Sciences. Get it on Amazon.
Hannaman, R. A., Bullock, L., Hatchell, C. A., & Yoffe, M. (2016). Internal medicine review core curriculum, 2017-2018. CO Springs, CO: MedStudy.
Therapeutic Guidelines. Melbourne: Therapeutic Guidelines Limited. https://www.tg.org.au [Accessed 2021].