Atypical renal cyst raises diagnostic and therapeutic problems. The authors
report a case of atypical renal cyst which raised numerous diagnostic and
therapeutic problems. The authors discuss theses problems in the light of t
his case. A farmer consulted for right lumbar pain without hematuria and hy
daturia. Hydatic serology was negative. Ultrasonography and CT scan showed
atypical cyst in favour of hydatic cyst. Surgical investigations showed a n
ecrotico-hemorragic cyst, and cystectomy was performed. Histological examin
ation revealed a chronic inflammatory process without malignancy. One year
after the operation, clinical and radiological examination were normal.