Acute interstitial nephritis. A case characterized by increase in serum IgG, IgM, and IgE concentrations. Eosinophilia, and IgE deposition in renal tubules.

A case of acute interstitial nephritis with a distinct immunopathologic pattern was seen. The relevant findings included elevated levels of serum IgG, IgM, and IgE; persistent eosinophilia; prominent granular and electron-dense depositions of IgE and C3 in renal tubules, as demonstrated by direct immunofluorescent and electron microscopic procedures; persistent failure to demonstrate anti-basement membrane antibodies (both glomerular and tubular); and hypocomplementemia. The findings in our case suggest a type of acute interstitial nephritis with a somewhat different clinical outlook. In this respect, serial assays of complement components and IgE in serum and kidney tissue and determinations of circulating anti-basement membrane antibodies (both glomerular and tubular) may be of particular importance.