[Primary hydatid cyst of the spleen].

We present the case of a 63 year male patient, natural from Lima. He has been in a cattle zone seven years ago. His illness had an insidious start and a progressive course; from a month ago he had malaise associated with nausea, abdominal distention and occasional vomiting; denies weight loss. In the clinical examination was lucid and stable, and without jaundice. The abdomen was soft without signs of peritoneal irritation; in the left flank there was a large mass with defined limits, painless, attached to deeper layers. Auxiliary tests: CBC: eosinophils 5.74%; the levels coagulation, biochemistry and electrolytes were normal. Total protein, albumin, bilirubin levels, aminotransferasas (ALT an AST) and alkaline phosphatase were normals. Arco V: 248 (N<22) and positive Inmunoblot to Echinococcus granulosus. Abdominal ultrasound showed two cystic formations of 161 x 95 mm and 146 x 130 mm, that moving the left kidney and spleen. Axial tomography was interpreted as a large ovoid formation (12 x 18 x 27 cm) dependent on spleen, lobed, hypodense, with rounded focal areas with less attenuation in the peripheral area; without contrast enhancement, compatible with hydatid cyst Gharbi III. The surgical intervention was a partial cystectomy plus external drainage; the surgeon found a giant splenic hydatid cyst, occupied the left hypochondrium and the left flank; had thick walls, daughter vesicles and clear liquid inside. The cystic lesion was attached to the descending colon, stomach, and left diaphargm. We present this case because the splenic hydatid cyst is rare, even less as a single site, and their prevalence does not exceed 1 %.