Acute interstitial nephritis
This is an immune reaction to drugs or infection.
It accounts for 2% of all acute renal failure but 25% of drug-induced renal failure.
Features include:
- acute renal failure
- hypertension
- systemic symptoms
- rash
- fever
- eosinophilia, raised IgE
>1% urinary eosinophils suggests diagnosis
Renal biopsy would show infiltration of the renal interstitium with:
- T lymphocytes
- macrophages
- plasma cells
Causes include:
- infections: hanta virus, leptospirosis, mycobacterium, staph, strep
- drugs: methicillin, NSAIDs, rifampacin, allopurinol, penicillin, cephalosporins, furosemide, thiazides, amphotericin, aspirin
- sarcoid
Lets move on to consider a hat-trick of causes of chronic interstitial nephritis
