Allergic Interstitial Nephritis

Allergic Interstitial Nephritis

Etiology :

70 % of cases due to adverse effect to medications

Drugs

1.Penicillins
2.Cephalosporins
3.Sulfa drugs
4.Allopurinol
5.Rifampin
6.Quinolones.

it happens from the first dose.As compared to Aminoglycosides take 5-10 days.
Infections (viruses,bacteria or fungi).Most common causes includes

1.Leptospirosis
2.Legionella
3.CMV
4.Rickettsia
5.Streptococci

Autoimmune disease

1.SLE
2.Sjogren syndrome
3.Sarcoidosis
4.Cryoglobulinemia

Dx: 

1.Rash
2.Fever
3.Joint pain
4.Eosinophilia
5.Increased serum IgE

Best initial test-urinalysis

1.Eosinophiluria (Wright or Giemsa stain)
2.Hematuria
3.Proteinuria (<2g hrs="" p="">
Most accurate test

1.Biopsy
2.Rarely performed

Rx
1.Stop the offending agent
2.+/- corticosteroids