Medical treatment for an isolated renal multilocular hydatid cyst in an elderly: a case report.

Background: Almost all cases of renal hydatid cysts need surgical intervention for treatment. We report a case of isolated renal hydatid cyst treated successfully only with medical therapy.
Case Presentation: This case is a 79-year-old veterinarian presented with right flank pain, hydatiduria and positive echinococcus granulosus serology. A 70*50 mm cyst with daughter cysts in mid-portion of right kidney on presentation was changed into a 60*40 mm cyst without daughter cysts at last follow-up. Due to patient's refusal of surgery, our patient received medical treatment including praziquantel and albendazole. After completion of first round of treatment, recurrence occurred and the same treatment was repeated. At last, the cyst became inactive and calcified with negative serology and no clinical symptoms under medical treatment.
Conclusion: The treatment of choice in renal hydatid cyst is surgery; although there are some reports about the efficacy of medical treatments for hydatid cysts but lower rates of recurrence and higher efficacy put surgery in a superior position compared to medical approaches. Our case showed relative success of medical treatment, despite the presence of a large multilocular renal involvement. Thus, medical therapy without surgery can be considered in very particular cases with isolated renal hydatid cysts.