Unusual tubular calcification of a nephrostomy tract.

Unusual tubular calcification occurred in the nephrostomy tract of a 30-year-old male, 6 months after percutaneous nephrostolithotomy. To our knowledge, this phenomena has not been previously reported. The main radiologic differential diagnoses are focal dystrophic calcification and vascular calcification. The etiology is unknown but may have been related to the patients' tendency to form renal calculi. The temporal sequence of events and the location of the nephrostomy catheter which correlated with the calcification suggests the correct diagnosis.