Abdominal cocoon, also known as sclerosing encapsulating peritonitis, which is characterized by part or all of the small intestine is wrapped by the fibrous tissue membrane like the silkworm cocoon(1, 2, 7). Cryptorchidism is caused by abnormal testicular descent, one of the common diseases of the urinary system in children, which can be divided into intra-abdominal type and extra-abdominal type, the main sign is the absence of testicle in the affected scrotum(4–6).
Primary abdominal cocoon is rare, most cases are diagnosed during exploratory laparotomy. It often present with unexplained abdominal pain, abdominal distension or intestinal obstruction(8–10). Typical abdominal CT shows that the bowel is twisted and folded in the shape of accordion or banana, which is surrounded by the layer of dense linear membrane, and the mesenteric and blood vessels are often involved, twisted and deformed(7, 11, 12). The etiologies and pathogenesis are unknown, part of patients with the absence of the greater omentum which are related to the congenital developmental abnormalities, the possible reason is that the greater omentum descends and wraps the intestine to form the smooth and dense cocoon membrane(13). Cryptorchidism mainly manifests as the absence of testicle in the affected scrotum(4, 5, 14), CT could accurately show the location of cryptorchidism in the abdominal cavity(15), and this disease may be related to the obstruction of testicular descent during embryonic development(14). In this case, he was admitted to the hospital due to unexplained intermittent abdominal pain, preoperative CT showed suspicious abdominal cocoon and right cryptorchidism. The patient did not have specific clinical manifestation, it was difficult to distinguish from other gastrointestinal diseases and seriously affected the accuracy of preoperative diagnosis.
Finally, primary abdominal cocoon and right intra-abdominal cryptorchidism were not diagnosed until the operation.
At present, surgery should be the first choice for abdominal cocoon with severe acute abdomen symptoms(9, 16, 17), the main principle is to separate and peel off the cocoon membrane, loose the adhesion between the intestines to release the movement vitality. The cocoon membrane may wrap the intestine and form the huge mass, which is easily misdiagnosed as the gastrointestinal tumor. We should improve the understanding of abdominal cocoon to avoid the short bowel syndrome which is caused after mistaken resection of the intestine. Few cases of abdominal cocoon with cryptorchidism, especially intra-abdominal cryptorchidism, the related mechanism of this patient may be that the abnormally developed greater omentum wrapped the intestine and hindered the descending of the testicles. Studies had shown that abdominal cocoon had a better prognosis after surgical treatment(18), this patient recovered well during the one-year follow-up.
In conclusion, this article reports a rare patient with primary abdominal cocoon and right intra-abdominal cryptorchidism. Although the relationship between the two diseases is not yet clear, they may all related to congenital developmental abnormalities. Therefore, when treating patients with abdominal cocoon or cryptorchidism, we should pay attention to identifying whether the patient has two diseases at the same time to better save the life of the patient.