Renal biopsies in cystic fibrosis.

Pharmacokinetic studies on antibiotics as well as other studies on renal function indicate renal malfunction in cystic fibrosis. Renal biopsies from two children, and post mortem examination from one child, with this disorder were normal by light microscopy and close to normal by immunofluorescence examination and transmission and scanning electron microscopy, even in cases with advanced disease and marked renal malfunction. Renal biopsy interpretation thus seems to be of little value in the evaluation of renal malfunction in this disorder, and this suggests that the functional abnormalities are caused by metabolic/biochemical defects.