Keywords
hydatid cyst - uncommon location - lesser omentum
A 22-year-old male presented with right upper abdominal pain for a duration of 3 months.
There was a single spike of high-grade fever of 102°F (38.9°C). It was also associated
with early satiety. There were no features suggestive of cholangitis. Per-abdomen
examination was grossly normal. He was evaluated with an ultrasound abdomen which
revealed a cystic lesion of size 8.6 × 7 cm in segment VI and VII of liver with dependent
debris and calcific foci. Further evaluation with a triphasic contrast-enhanced computerized
tomography abdomen revealed a large cystic lesion of size 7.8 × 8.9 × 10.5 cm in relation
to the left lobe of the liver with extension into subhepatic and gastrohepatic recess
with a thin concentric membrane within the cyst ([Fig. 1A, B]). Serological testing showed elevated anti-Echinococcus antibodies (immunoglobulin G; 1:1,600 by ELISA [enzyme-linked immunosorbent assay]
method). With a provisional diagnosis of hydatid cyst, the patient was planned for
exploratory laparotomy after a preoperative course of Albendazole for 2 weeks. Intraoperatively
there was a cystic lesion seen in the lesser omentum. However, the cyst was seen to
be free from the liver surface and was in close relation to the lesser curvature of
the stomach ([Fig. 1C]). Pericystectomy was performed. A thick-walled single-layered cyst was retrieved
from within the mass; however, no daughter cysts were seen ([Fig. 1D]). The histopathological examination of the sections from the cyst showed thick,
avascular, eosinophilic laminated membrane with a few hooklets, with overall features
consistent with hydatid cyst. The postoperative course was uneventful, and the patient
was discharged on postoperative day 4. In view of the fact that the cyst was excised
in toto and there was no intraoperative spillage of the cyst contents, he was not
advised postoperative Albendazole therapy.
Fig. 1
(A) Axial CT scan image showing cystic lesion in relation to the left lobe of the liver
with extension into gastrohepatic space (white arrow) and containing a thin concentric membrane (orange arrow). (B) Coronal CT scan image showing the cystic lesion in the lesser omentum with the concentric
membrane within (orange arrow). (C) Intraoperative image showing the mass in the lesser omentum which was seen to be
free from the lower edge of the liver (blue arrow). (D) Cut section of the resected specimen showing a thick membranous cyst which was retrieved
from within the resected mass. CT, computed tomography.
Hydatid disease is a parasitic disease caused by the larval stage of the tapeworm
Echinococcus primarily affecting the liver and lung.[1] The most common location of hydatid cyst is the liver, and the most common extra-abdominal
site is lung.[2] Ours was a unique case in terms of the organ of origin from the lesser omentum,
with very few number of case reports available in the literature with hydatid cyst
arising from the lesser omentum.[3]
[4]
[5] Omental hydatid should be excised, preferably by the open laparotomy approach or
even laparoscopically. Special precautions should be taken like covering the rest
of the peritoneal cavity with betadine or 20% saline-soaked sponges to avoid dissemination
of the disease in case of inadvertent rupture of the cyst.