mesenteric and omental mesothelial cysts are responsible for only 1 in 100,000 of adult hospital admissions , and are thus left low on the list of differential diagnoses for abdominal pain .
further evaluation of such masses is first directed at determining a tissue origin if possible .
lymphangioma accounts for the most commonly reported of such lesions , followed by enteric cyst , enteric duplication cyst , non - pancreatic pseudocyst , and mesothelial cyst .
gastrointestinal leiomyomas ( cystic spindle cell tumors ) in particular have been reported to undergo central liquefactive necrosis and hemorrhage , appearing as cystic mesenteric or omental lesions on imaging .
the pathogenesis of a mesothelial cyst involves failed coalescence of mesothelial - lined surfaces , typically involving the small bowel , mesentery , or mesocolon .
imaging usually demonstrates a fluid - filled cavity without a readily identifiable wall . unlike lymphangiomas ,
however , given the overlapping features of such cystic intra - abdominal masses on imaging , definitive diagnosis is made on thorough histopathologic analysis of the resected specimen .
a 41 year - old male presented to our emergency department with periumbilical abdominal pain and associated intermittent nausea and vomiting of several days duration .
medical history was significant only for hypertension , and he was noted to have had prior appendectomy and posterior spinal fusion .
physical examination revealed an obese abdomen with localized tenderness to palpation over the mid - abdomen without peritoneal signs .
initial emergency department laboratory workup included cbc and cmp , which revealed a hypokalemic hypochloremic metabolic alkalosis .
this patient was admitted to the general surgery service and treated conservatively with iv rehydration and empiric antibiotics .
accounting for his chronic diarrhea , chief differential diagnosis at that time included sclerosing mesenteritis , small bowel diverticulitis , and small bowel carcinoid tumor .
5-hiaa , octreotide scan , and chromogranin a were within normal limits , lowering suspicion for neuroendocrine tumor . with conservative management ,
he initially reported improvement in his abdominal pain ; however , his pain never completely resolved and he eventually reported postprandial exacerbation . on hospital day 13 , the decision was made to perform diagnostic laparoscopy with potential mass and/or small bowel resection .
the mass present on ct was identified intraoperatively in the mid - jejunal mesentery after an adhesion between two adjacent loops of jejunum was separated ( fig .
the mass was resected along with a 15  cm segment of the involved jejunum , followed by primary anastomosis .
his postoperative course was uneventful , and he was discharged shortly thereafter with resolution of his pain . on clinic follow - up , he has remained without pain .
h&e staining of the specimen demonstrated spindle cells and signs of coagulation necrosis with ghost cells showing prominent eosinophilic staining fig .
cd117 and dog1 staining were negative ( not shown ) , excluding gastrointestinal stromal tumor .
h&e staining of the specimen demonstrated spindle cells and signs of coagulation necrosis with ghost cells showing prominent eosinophilic staining fig .
cd117 and dog1 staining were negative ( not shown ) , excluding gastrointestinal stromal tumor .
mesenteric and omental cystic masses are uncommon , representing only 1 in 100,000 acute adult hospital admissions , although it is possible they occur with greater frequency but are missed or identified incidentally as most remain asymptomatic . further hindering their rapid diagnosis when symptomatic is their very nonspecific presentation including but not limited to abdominal pain which is often chronic in nature , mass , or distension .
this patient presented with the additional complaint of nausea and vomiting , and it is likely that local mass effect was involved , as concluded by other authors reporting on similar intra - abdominal cystic masses .
the exact etiology underlying the necrosis of this patient s mesothelial cyst and its contribution to his abdominal pain is unclear .
it is likely that this patient s cyst simply outgrew its own perfusion , although a possible contribution by some physiologic stressor is worth consideration .
the mainstay of treatment for symptomatic lesions is complete surgical excision , , as recurrence of incompletely excised cysts has been noted by other authors .
fortunately for this patient , surgery seems to have been curative as he remains well on follow - up .
rare etiologies of gastrointestinal upset and abdominal pain , while reasonably left low on the differential list , ought not to be excluded from it completely .
unfortunately however , it appears that mesothelial cyst and other intraabdominal cystic masses often fail to reveal themselves on physical examination and leave no characteristic clues in recent patient history , only becoming apparent nonspecifically on advanced imaging .
the routine practice of ct imaging and the low threshold employed at some institutions for its use is a matter of controversy outside the scope of this case report ; however in the case of our patient , it was diagnostically important , appropriately directed treatment towards surgical management , and led to a therapeutic outcome .
routine histopathological examination of resected tissue specimens is also of value in excluding malignancy , arriving at a specific diagnosis and confirming total resection of lesions that are likely to recur if incompletely excised .
walter beversdorf , ms-4 : writing of case report , editing , proofing , submitting .
this research did not receive any specific grant from funding agencies in the public , commercial , or not - for - profit sectors .
written informed consent was obtained from the patient for publication of this case report and accompanying images .
a copy of the written consent is available for review by the editor - in - chief of this journal on request .
 highlightsmesenteric cystic masses account for a very small fraction of abdominal pain cases.symptoms arise likely as a result of mass effect , even when these lesions are small.on detection of these lesions by imaging , it is important to exclude neuroendocrine tumors.complete surgical excision is curative of symptoms caused by local mass effect.histopathological examination of specimens is the definitive means to differentiate between such lesions , that appear similarly on imaging . 
Introduction
Presentation of case
Histopathologic examination
Discussion
Conclusion
Author contribution
Ethical approval
Conflicts of interest
Consents
Guarantor