RESUMO
INTRODUCTION: Hydatidosis is a zoonosis caused by larvae of the hydatid tapeworm Echinococcus granulosus, which usually affects the liver, lung, myocardium, brain and bones. On rare occasions hydatid cysts give rise to peripheral neurological manifestations. CASE REPORT: Male, aged 72, who had received a pacemaker as a consequence of a complete auriculoventricular block. During implantation, one hepatic and two pelvic hydatid cysts were discovered. Consulted doctor about right inguinal pain, which irradiated to the lumbar region and along the inner and posterior sides of the thigh, down to the ankle. Exploration revealed a lump in the right iliac fossa and in the lower right limb, hypaesthesia in the anterior side of the thigh, paresis on bending the hip and on extension of the knee, and patellar areflexia. Computerised axial tomography revealed growth of the pelvic cysts and compression of the gluteal veins. Electromyographic exploration of the right quadriceps showed denervation and reinnervation activity. CONCLUSION: Of all cases of abdominal hydatidosis, 6.7% presented extra hepatic affectation and only 0.7% were seen to have pelvic hydatid cysts. These usually give rise to disorders due to local compression of the genital organs, the urinary tracts, and vascular and bony structures. Lesions in the lumbosacral plexus, however, have only been reported on very few occasions