Spontaneous drainage of an asymptomatic recurrent hydatid cyst of the sacrum.

STUDY DESIGN: A case report. OBJECTIVE: This is an unusual presentation of recurrent hydatid disease. Spillage of a hydatid cyst was previously reported in a symptomatic case of primary spinal hydatid disease. However, we did not find any examples of spontaneous discharge of hydatid cyst fluid in an asymptomatic case in the literature. SUMMARY OF BACKGROUND DATA: Bone hydatid cysts occur in 1% to 2.5% of all patients with hydatid cyst disease, whereas 50% of bone hydatidosis cases are spinal. Diagnosis is difficult and patients usually present with neural compression symptoms. Surgery and antihelmintic medicine administration are considered as the treatments of choice. METHODS: In this report, a 35-year-old male patient, who underwent surgical and antihelmintic medical treatment 2 years previously, had a leaking cyst without neurologic symptoms. The patient underwent excision of multiple parasacral cysts from a posterior approach. Medical antihelmintic treatment was used after surgery. RESULTS: The postoperative period was uneventful. Follow-up MRI scans were performed at 6, 12, and 18 months after surgery. The few residual anterior perisacral cysts had, in fact, become smaller. CONCLUSION: The recurrence period of spinal hydatid disease may be silent without any neurologic deficits or pain; the only clinical manifestation may be leakage from a cyst. Curative therapies remain unlikely, but periodic follow-up MR images are advisable for early diagnosis of recurrence in order to obtain effective treatment.

Echinococcosis granulosus/cysticus of the tibia.

Hydatid disease is caused by the parasitic tapeworm Echinococcus. There are three species: E. granulosus, E. alveolaris and E. voegeli. Only E. alveolaris and E. granulosus are important for human infections. These two species are totally divergent in their manner of infestation. Hydatid disease is a rare parasitic disease that primary involves the liver and the lung. Skeletal disease is rare, accounting for less than 2% of all hydatid lesions, and often presents as a clinical and radiologic diagnostic problem. The skeletal involvement is usually due to secondary extension after haematogenous spread of the infection. The vertebral column, the pelvis and the skull are most commonly involved. Treatment is also difficult because of the invasive nature of bony involvement and the spillage of fluid with subsequent contamination seeding. We present a case of primary hyatid cyst of the tibia. We point out the importance of considering osseous hydatidosis in the differential diagnosis of destructive bone lesions and the necessity of radical resection.

CT findings in skeletal cystic echinococcosis.

PURPOSE: To evaluate the CT findings of skeletal cystic echinococcosis. MATERIAL AND METHODS: CT findings of 7 patients with pathologically confirmed skeletal cystic echinococcosis were evaluated. RESULTS: There were 4 men and 3 women, aged 36-75 years. Hydatid cysts were located in the spine (n=2), a rib (n=3), the pelvis and a vertebra (n=1), the pelvis and the left femur (n=1). The size of the lesions varied from 1 cm to 15 cm. CT showed well defined, single or multiple cystic lesions with no contrast enhancement, no calcification, no daughter cysts, and no germinal membrane detachment. The cystic lesion had a honeycomb appearance in 2 cases; there was pathologic fracture in 2 cases, bone expansion in 5 cases, cortical thinning in 6 cases, cortical destruction in 6 cases, bone sclerosis in 1 case, and soft tissue extension in 6 cases. CONCLUSION: Preoperative differential diagnosis of skeletal cystic lesions should include cystic echinococcosis, especially in endemic areas, since this diagnosis may easily be missed unless kept in mind.