Diagnosis of small bowel obstruction secondary to eosinophilic enteritis using nasointestinal ileus tube and enteroscopy: a case report.

A 52-year-old female was admitted with a 15-day history of intermittent abdominal pain, which had exacerbated over the preceding 3 days. The pain was generalized and colicky, accompanied by abdominal distension and reduced bowel movements and flatus. Initial symptomatic treatment at another hospital provided transient relief without elucidating the cause. The patient reported no history of allergic or autoimmune diseases, and parasitic infection was excluded. Physical examination revealed generalized abdominal tenderness without rebound tenderness, palpable masses, or shifting dullness. Bowel sounds were hyperactive. Laboratory investigations showed a white blood cell count of 4.2 × 10⁹/L, with an eosinophil percentage of 1.9% (absolute count 0.08 × 10⁹/L). Immunological markers and tumor markers (CEA, AFP, CA19-9, CA125) were within normal limits. Abdominal CT revealed segmental small bowel wall thickening, luminal stenosis with mucosal enhancement (Fig.  1 ). Fig. 1 Abdominal computed tomography (CT) findings. Abdominal CT showed thickening of the intestinal wall in multiple segments of the small intestine, with luminal narrowing. The maximal dilated bowel diameter was approximately 3.5 cm. The narrowed intestinal segment was approximately 50 cm long (green arrows). A Axial view, ( B ) Coronal view, ( C ) Sagittal view Abdominal computed tomography (CT) findings. Abdominal CT showed thickening of the intestinal wall in multiple segments of the small intestine, with luminal narrowing. The maximal dilated bowel diameter was approximately 3.5 cm. The narrowed intestinal segment was approximately 50 cm long (green arrows). A Axial view, ( B ) Coronal view, ( C ) Sagittal view The patient’s abdominal CT scan revealed small bowel obstruction with a maximal dilated bowel diameter of approximately 3.5 cm. Enteroscopic intervention at this stage was deemed high-risk due to the potential for increasing intraluminal pressure and exacerbating the obstruction. To ensure procedural safety and optimize conditions for endoscopy, a nasointestinal ileus tube was placed for decompression as the initial management. Following 5 days of decompression, a follow-up abdominal CT scan demonstrated a marked improvement, with the maximal dilated bowel diameter reduced to approximately 2.5 cm. The patient’s symptoms of abdominal pain and abdominalbloating distension have easedbeen alleviated. The nasointestinal ileus tube was then removed, and balloon-assisted enteroscopy was subsequently performed uneventfully. Approximately 50 cm of the proximal ileum exhibited diffuse congestion, edema, and mucosal erosion, predominantly along the fold crests, with a single identifiable stricture (Fig.  2 ). Retrograde (anal-route) enteroscopy advanced approximately 200 cm, showing normal mucosa without inflammation. Fig. 2 Painless balloon-assisted enteroscopy findings. Enteroscopy revealed a 50 cm-long segment of diffuse congestion and edema in the upper ileum. A , B The inflammation proximal to the stenosis was mild. C Inflammation distal to the stenosis was more pronounced, with visible erosion, particularly at the crests of the folds. D A single tight stricture through which the endoscope barely passed Painless balloon-assisted enteroscopy findings. Enteroscopy revealed a 50 cm-long segment of diffuse congestion and edema in the upper ileum. A , B The inflammation proximal to the stenosis was mild. C Inflammation distal to the stenosis was more pronounced, with visible erosion, particularly at the crests of the folds. D A single tight stricture through which the endoscope barely passed Histopathological analysis of the ileal biopsies showed chronic mucosal inflammation, villous blunting, glandular dilatation and distortion, and a dense eosinophilic infiltrate within the lamina propria. The peak eosinophil count was more than 50 per high-power field. Given the degree of bowel wall thickening observed on CT, the inflammatory process was inferred to extend into the deeper layers, possibly the submucosa or muscularis propria (Fig.  3 ). Fig. 3 Histopathological features of the intestinal mucosa. Hematoxylin and eosin staining showed chronic inflammation of the ileal mucosa, with reduced villi, partial glandular dilation and distortion, and a dense eosinophilic infiltrate within the lamina propria. The peak eosinophil count was > 50 per high-power field. Given the degree of bowel wall thickening observed on CT, the infiltration was inferred to extend beyond the mucosa, possibly into the submucosa or muscularis propria. A Magnification ×200, ( B ) Magnification ×400 Histopathological features of the intestinal mucosa. Hematoxylin and eosin staining showed chronic inflammation of the ileal mucosa, with reduced villi, partial glandular dilation and distortion, and a dense eosinophilic infiltrate within the lamina propria. The peak eosinophil count was > 50 per high-power field. Given the degree of bowel wall thickening observed on CT, the infiltration was inferred to extend beyond the mucosa, possibly into the submucosa or muscularis propria. A Magnification ×200, ( B ) Magnification ×400 On the second day after enteroscopy, pathological findings confirmed the diagnosis of EE. Intravenous methylprednisolone was administered immediately, resulting in a significant clinical response. The patient’s abdominal pain was markedly relieved, and oral water intake was gradually resumed. After 5 days of intravenous methylprednisolone (60 mg daily), the therapy was switched to oral prednisone (initial dose 40 mg daily). The patient was discharged on day 11. The prednisone dose was tapered to 30 mg daily at 1 month after discharge, to 15 mg daily at 3 months, and was completely discontinued by 6 months. At the 12-month follow-up, the patient remained completely asymptomatic with no recurrence of abdominal pain or obstructive symptoms.

Approximately 85–90% of small bowel obstructions are attributable to adhesions, hernias, and neoplasms. The remaining etiologies include peritoneal carcinomatosis, endometriosis, and inflammatory bowel disease-related strictures [ 1 ]. Eosinophilic gastrointestinal disorders (EGIDs) are rare, with an estimated population prevalence of 1–30 per 100,000 [ 2 ]. Eosinophilic enteritis presenting primarily as SBO is exceptionally uncommon, and its diagnosis is often complicated by nonspecific clinical and imaging findings. This report details a case of ileal EE with normal peripheral eosinophil counts, which was diagnostically elusive on initial assessment. The obstruction was initially managed with a nasointestinal ileus tube, and the definitive diagnosis was subsequently established via enteroscopic biopsy. The patient responded favorably to glucocorticoid treatment, achieving sustained remission.

This case highlights that eosinophilic enteritis should be considered in the differential diagnosis of small bowel obstruction, irrespective of peripheral eosinophil counts. Enteroscopic biopsy is essential for definitive diagnosis. Initial management with a nasointestinal ileus tube effectively relieve obstruction and create optimal conditions for subsequent endoscopic evaluation. Accurate pathological diagnosis is crucial for instituting effective medical therapy, thereby improve clinical outcomes and help avoid unnecessary surgery.

Eosinophilic gastroenteritis (EGE) is a rare, heterogeneous disorder characterized by eosinophil-predominant infiltration of the gastrointestinal tract [ 3 ]. According to the Klein classification, EGE is categorized into mucosal, muscular, and serosal subtypes, with clinical manifestations varying by the depth and extent of involvement [ 4 ]. Mucosal disease often causes diarrhea, malabsorption, and protein-losing enteropathy; muscular involvement can lead to obstructive symptoms; serosal involvement may present with ascites or peritonitis [ 5 ]. This clinical heterogeneity contributes to frequent misdiagnosis. A comprehensive literature search was conducted in PubMed, Embase, the Cochrane Library, Web of Science, and CNKI from database inception to November 2025 for pathologically confirmed cases of EE presenting with SBO as the primary manifestation. The search used the terms: (eosinophilic enteritis OR eosinophilic gastroenteritis) AND (small bowel obstruction OR intestinal obstruction OR bowel obstruction) AND (case report OR clinical case OR case series). This search identified only 35 previously reported cases (Table 1 ). [ 6 – 34 ] To our knowledge, this is a rare report detailing the successful combined use of a nasointestinal ileus tube and enteroscopy to facilitate both the non-operative management and definitive diagnosis of EE presenting with SBO. Table 1 Summary of eosinophilic enteritis with small bowel obstruction: a review of published cases Author, year Age/Gender Clinical manifestations Management Nasointestinal ileus tube Enteroscopy Surgery Beatriz de Rienzo-Madero, 2023 84/M Small bowel obstruction Budesonide and Metronidazole No Yes No Cong Dai, 2024 53/M Intestinal obstruction Prednisone No Yes No Min Young Yun, 2007 51/F Small bowel obstruction Resection of the ileum No No Yes Takahiro Uenishi, 2003 37/M Acute Intestinal obstruction Resection of the ileum No No Yes José Aguilar-Jiménez, 2015 69/M High bowel obstruction Resection of the bowel No No Yes Aloisio Antonio Gomes de Matos Brasil, 2013 49/M Acute Intestinal obstruction laparoscope and Corticosteroid No Yes Yes Kian Chai Lim, 2011 31/M Duodenal obstruction Prednisone No Yes No Mark C. Rumans, 1987 60/M Biliary and Duodenal obstruction laparotomy No No Yes Clifford Atuiri, 2024 30/M Small bowel obstruction Resection of the small bowel No No Yes Karoline Kant, 2021 45/F Small bowel obstruction Resection of the small bowel No No Yes M. J. Farahvash, 1990 17/F Biliary and Duodenal obstruction laparotomy No Yes No Julian E. Losanoff, 1995 50/M Intestinal obstruction Salazopyrin and Prednisolone No No Yes Katharine Boyd, 2017 55/M Small bowel obstruction Resection of the small bowel No No Yes J. M. Álamo Martínez, 2004 50/F Intestinal obstruction Resection of the bowel No No Yes Marina Puya Gamarro, 2018 52/M Intestinal obstruction Budesonide No Yes No Yuhki Arai, 2022 5/M Intestinal obstruction Resection of the bowel No No Yes J. J. Martínez Crespo, 2002 40/M Intestinal obstruction laparotomy No No Yes J C Box, 1997 ——  bowel obstruction Resection of the bowel No No Yes J D Wig, 1995 —— Intestinal obstruction Resection of the bowel No No Yes —— Intestinal obstruction Resection of the bowel No No Yes —— Intestinal obstruction Resection of the bowel No No Yes Philip Alexander, 2003 —— Acute Intestinal obstruction Resection of the bowel No No Yes J H Marymont, 1967 —— Small bowel obstruction Resection of the small bowel No No Yes J H Caldwell, 1978 —— Intestinal obstruction Resection of the bowel No No Yes —— Intestinal obstruction Resection of the bowel No No Yes —— Intestinal obstruction Resection of the bowel No No Yes —— Intestinal obstruction Resection of the bowel No No Yes —— Intestinal obstruction Resection of the bowel No No Yes C S Wang, 1990 60/M Intestinal obstruction Resection of the bowel No No Yes T Karande, 1996 8/F Acute Intestinal obstruction laparotomy No No Yes J A Alvarez Sánchez, 1994 —— Intestinal obstruction Resection of the bowel No No Yes B Remacha Tomey, 1999 —— Intestinal obstruction Corticosteroid No Yes No Zhi guang Zhang, 2003 39/M Intestinal obstruction Prednisone No Yes No Guang ying Song, 2002 42/F Intestinal obstruction Prednisone No Yes Yes Sai nan Zhou, 2014 29/F Intestinal obstruction Resection of the ileum No No Yes Summary of eosinophilic enteritis with small bowel obstruction: a review of published cases The Talley criteria (1990) are commonly employed for diagnosis, include: (1) GI symptoms; (2) eosinophilic infiltration on biopsy (typically defined as > 20 eosinophils per high-power field) or eosinophilic ascites; (3) exclusion of parasitic infection; and (4) absence of extraintestinal eosinophilic disorders [ 35 ]. Notably, up to 26% of EGE patients have normal peripheral eosinophil counts [ 36 ], emphasizing the critical role of tissue biopsy. In this case, the normal laboratory values and nonspecific imaging findings initially raised differential diagnoses, including Crohn’s disease (CD), cryptogenic multifocal ulcerous stenosing enteritis (CMUSE), NSAID-related enteropathy, and ischemic enteropathy. These were rigorously excluded: histopathology revealed no granuloma formation (excluding CD); serological tests including ANCA were normal; the patient denied any history of NSAID use; and there were no clinical or radiological features suggestive of intestinal ischemia. The clinical, radiological, and histopathological findings were most consistent with a diagnosis of eosinophilic enteritis. While EE typically presents with abdominal pain, nausea, and vomiting, acute obstruction or perforation is rare [ 37 ]. Consequently, EE is seldom considered initially in patients presenting with severe obstructive symptoms. Among the 35 reported SBO cases, most were diagnosed post-operatively via histopathology of resected specimens; only seven prior cases was diagnosed by enteroscopy. Nasointestinal ileus tube (using long tubes, e.g., 300 cm) is an effective strategy to relieve partial SBO, potentially obviating emergent surgery [ 38 ]. In our patient, decompression not only alleviated symptoms but also enabled safer endoscopic evaluation. The use of carbon dioxide insufflation during enteroscopy further minimized the risk of distension-induced complication. Double-balloon enteroscopy has revolutionized small bowel diagnostics, yet its application in confirming EE remains infrequently reported. We propose that the synergistic use of nasoenteric decompression and enteroscopy provides a valuable diagnostic strategy for EE presenting with SBO. This approach may be considered to support the development of successful non-operative management strategies, potentially reducing patient morbidity. The spontaneous remission of eosinophilic gastroenteritis-related inflammation and obstruction is extremely rare, and intestinal rest (decompression) can only play an auxiliary role in relieving symptoms, and the anti-inflammatory effect of glucocorticoids is the core for the remission of the disease in this case. First-line therapy for subacute or chronic mucosal EE typically involves glucocorticoids [ 39 ]. Our patient exhibited an excellent response to methylprednisolone, avoiding surgical intervention. Alternative or adjunctive agents include cromolyn sodium, ketotifen, and leukotriene receptor antagonists [ 40 ]. Recent advances in biologic therapies and enhanced imaging techniques offer new avenues for managing refractory or steroid-dependent cases [ 41 ].