Muscle-Sparing Approach for Recurrent Hydatidosis of the Thigh and Psoas: Report of a Rare Case

A 46-year-old male shepherd presented with a mildly painful mass 4.5 cm in diameter localized at the right groin and thigh, diffuse edema involving the right leg lasting for 2 weeks, and fever. The patient had had eight previous operations for diffuse hydatidosis with reported intraperitoneal seeding, but further information was unavailable. Laboratory tests are shown in Table 1. An abdominal ultrasound (US) and a Doppler US of the right leg detected the presence of multiple and partially confluent cysts localized up to the Scarpa’s triangle. A computed tomography (CT) scan detected a multi-cystic 18-cm mass originating from the psoas muscle (Figure 1, I and II). Other cysts were localized deeply and behind the muscular aponeurotic plane of the femoral quadriceps and abductor muscles (Figure 1, III and IV). All these findings were suggestive of diffuse hydatidosis and the patient was promptly operated on with a musclesparing approach, for which a written consent was obtained. Piperacillin/tazobactam was administered from the date of admission to the day of surgery. Preoperative prophylaxis with benzimidazole derivatives was not performed due to the extent of the disease, the history of recurrences, and the need to perform the operation promptly to reduce the symptoms. At surgery, the retroperitoneum was accessed and tissues surrounding the cysts were covered with sponges soaked with hypertonic saline. The cystic content was evacuated and the interior of the cyst was repeatedly washed with protoscolicides. Due to the tight adhesions with the peritoneal sac, only the lateral-lower portion of the cystic wall could be resected. No daughter cyst was found. Subsequently, the right thigh was anteriorly incised and the cysts were evacuated. The washing treatment was repeated but extensive resection was avoided to prevent any risk of unnecessary damage. Histopathological examination did not detect viable protoscolices and routine cultures performed to individuate other pathogens were negative. A CT scan performed before discharge showed the integrity of the psoas muscle (Figure 2, I and II) and the lack of residual cysts in the thigh with conservation of the muscular structures (Figure 2, III and IV). The patient was discharged after 11 days with 6 months of administration of mebendazole. Further investigations could not be performed because the patient missed the planned follow-up.