Zoonotic Transmission of Hepatic Hydatid Cyst from Domestic Dogs: A Case Report from an Urban-Marginal Area in Ecuador

Abstract

BACKGROUND Hepatic hydatidosis, or echinococcosis, is a zoonosis with worldwide prevalence and is potentially lethal in humans. This report presents a case of hydatidosis in a 40-year-old woman that was associated with a zoonotic transmission of Echinococcus granulosus from domestic dogs in an urban-marginal area of the city of Guayaquil, Ecuador. This report shows how early diagnosis and awareness favored the correct treatment of the disease. CASE REPORT A 40-year-old woman from the aforementioned sector presented the following symptoms: malaise, pain in the upper right hypochondrium, palpable mass, jaundice, and fever. Next, the patient's fecal samples were analyzed by direct coproparasitic methods, flotation, and sedimentation with centrifugation using saline solution, whereby the presence of Entamoeba histolytica eggs was determined. Likewise, she underwent an ultrasound, in which hepatic hydatid cysts were observed. Subsequently, the cysts were treated and surgically removed, and parasitic forms of E. granulosus were identified. Later, coproparasitic analysis of her 2 domestic dogs for coproantigen ELISA were performed, by which the presence of this cestode was also identified and confirmed. CONCLUSIONS Hydatidosis is a zoonosis that can affect the population, especially in endemic areas of developed and underdeveloped countries. In this case, hepatic hydatidosis was identified in a 40-year-old woman. Additionally, the presence of E. granulosus eggs was determined in the fecal matter of her dogs, which indicated that the patient's relatives and other people around them were exposed to this zoonosis.

Figure 1.

Presence of hydatid cyst at the level of the liver (red arrow) in the patient without biliary involvement, by means of computed tomography abdominal contrast with optiray, transverse plane. Focal lesions in the right hepatic lobe, hypodense, with a single septum and transverse diameter of 110 mm.

Figures 2.

(A, B) Microscopic identification of Echinococcus granulosus eggs (red arrow) in domestic dog feces obtained by direct coproparasitic technique, observed by optical microscopy at 40× and stained with Lugol.