Neotropical echinococcosis caused by Echinococcus vogeli in rural Huila, Colombia: report of two last cases in the last 35 years

Abstract

Background: Human polycystic echinococcosis is a parasitic infection caused by the larval stage of Echinococcus vogeli which occurs in rural areas of Latin America. Echinococcosis, and even more, human polycystic echinococcosis due to E. vogeli is neglected, particularly in Colombia. Methods & Materials: Cases report diagnosed by histological, morphometric and molecular techniques. Results: Case 1: A 9-year-old female from rural Huila, was brought to our hospital, due to an umbilical hernia (5 mm), confirmed by an abdominal ultrasound. This, and a subsequent computed tomography, revealed a lesion with solid and liquid components in the umbilical region, 40 mL, consistent with an echinococcal cyst. An uncomplicated resection of the tumor was performed (sized 6x4x3.5 cms), wall of 1 mm, multilocular cysts of 1 mm. The lesion was surrounded by fibrosis with eosinophilic and lymphoplasmacytic inflammatory infiltrate and a rim of histiocytes and multinucleated giant cells. Microscopic examination of resected tissue found vesicles containing protoscolices surrounded by PAS–positive membranes. The mean lengths of the rostellar hooks was 40 μm, then suggesting the diagnosis of E. vogeli echinococcosis. Case 2: 47-year-old woman patient from rural area Curillo, Caqueta, Colombia, with right upper quadrant and epigastric abdominal pain of 4-months of evolution with subsequent severe itching, dark urine and progressive jaundice, afebrile, with occasional emesis food content. Abdominal ultrasound found liver cystic lesion that compromises segments VI, VII and VIII. Resection of hydatid cyst was performed. PCR and sequencing Ev3-ev5 was performed. Samples submitted present Alignment: 188/188 with complete mitochondrial genome of E. vogeli. Nucleotide identity: 100% nucleotide to the original sequence described in Genbank E. vogeli identity. Conclusion: More undiagnosed cases of polycystic neotropical echinococcoses in Colombia should exist. A recent historical review of echinococcosis in Colombia showed that no previous cases have been reported from Huila, and even more, before the current cases (first reported in 35 years), only 3 previous reports were made. The review described 303 cases during 2009-2013, all of them due to E. granulosus and E. multilocularis (no cases of E. vogeli nor E. oligarthrus were reported). These recent cases highlights the possible emergence of this pathogen in certain areas of Colombia.