When Chronic Abdominal Pain Turns Acute: A Case of Right Paraduodenal Hernia

When Chronic Abdominal Pain Turns Acute: A Case of Right Paraduodenal Hernia | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report When Chronic Abdominal Pain Turns Acute: A Case of Right Paraduodenal Hernia Karam Alslaibi, Ibrahim Alnajjar, Tayseer Afifi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9122376/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 5 You are reading this latest preprint version Abstract Background Paraduodenal hernias (PDHs) are rare congenital internal hernias resulting from abnormal midgut rotation during embryologic development. They represent the most common type of internal hernia and are an uncommon but important cause of small bowel obstruction. Because clinical manifestations are often nonspecific and intermittent, diagnosis is frequently delayed, increasing the risk of strangulation and ischemia. Case Presentation: We report the case of a 43-year-old male with no significant medical or surgical history who presented with acute abdominal pain and a long-standing history of recurrent upper abdominal pain previously misdiagnosed as peptic ulcer disease. Contrast-enhanced computed tomography (CT) revealed a right paraduodenal hernia with partial small bowel rotation and features consistent with intestinal obstruction. The patient underwent urgent exploratory laparotomy, confirming herniation of jejunal loops through Waldeyer’s fossa. Surgical reduction and closure of the hernia defect were performed. The postoperative course was uneventful. Conclusion Right paraduodenal hernia should be considered in patients with recurrent unexplained abdominal pain without prior abdominal surgery. Early CT imaging and timely surgical intervention are essential to prevent complications. Clinical Trial Number: Not Applicable Paraduodenal hernia Internal hernia Small bowel obstruction Waldeyer’s fossa Case report Figures Figure 1 Figure 2 Figure 3 INTRODUCTION Paraduodenal hernias (PDHs) are rare congenital internal hernias caused by abnormal rotation and fixation of the midgut during embryological development. They account for approximately 50–55% of all internal hernias and are classified into left-sided (Landzert’s fossa) and right-sided (Waldeyer’s fossa) variants, with the right type being less common [ 1 , 2 ]. Internal hernias represent an uncommon but clinically significant cause of small bowel obstruction, particularly in patients without prior abdominal surgery. The incidence of internal hernias in the general population is low; however, they account for a meaningful proportion of unexplained bowel obstruction cases [ 3 ]. Delayed diagnosis is common because symptoms are often intermittent, nonspecific, and mimic other gastrointestinal disorders such as peptic ulcer disease, biliary colic, or functional dyspepsia [ 4 ]. Computed tomography (CT) is the imaging modality of choice and typically demonstrates clustered small bowel loops, abnormal mesenteric vessel orientation, and the characteristic “whirl sign” in cases complicated by volvulus [ 5 ]. Early recognition is crucial because surgical treatment is the definitive management and prevents life-threatening complications. We present a rare case of right paraduodenal hernia presenting as acute small bowel obstruction in a patient with a three-year history of recurrent abdominal pain previously misdiagnosed as peptic ulcer disease. CASE PRESENTATION Clinical Presentation A 43-year-old male patient with no known chronic medical illnesses and no previous surgical history presented to the emergency department with acute abdominal pain of three days’ duration. The pain was colicky in nature, progressively worsening, and radiated to the right upper quadrant. It was associated with repeated episodes of non-bilious vomiting and constipation, suggestive of mechanical intestinal obstruction. The patient denied any history of abdominal trauma, prior abdominal surgery, or similar acute episodes requiring hospitalization. Physical Examination On examination, the patient was hemodynamically stable with a blood pressure of 115/75 mmHg, a pulse rate of 105 beats per minute, and was afebrile. Abdominal examination revealed a soft but distended abdomen with localized tenderness and mild guarding in the right upper quadrant. Bowel sounds were diminished. No palpable masses, rebound tenderness, or signs of generalized peritonitis were detected. Past Medical History A detailed medical history revealed that the patient had experienced recurrent upper abdominal pain for approximately three years prior to this presentation. The episodes were intermittent and had been managed conservatively under a presumed diagnosis of peptic ulcer disease without significant clinical improvement despite medical therapy. There was no associated history of gastrointestinal bleeding, significant weight loss, chronic diarrhea, or other symptoms suggestive of inflammatory bowel disease. Laboratory Investigations Laboratory investigations demonstrated mild leukocytosis with a white blood cell count of 16.7 ×10⁹/L. Hemoglobin was 12.1 g/dL and platelet count was 270 ×10⁹/L. Biochemical parameters showed a random blood sugar of 112 mg/dL, urea level of 62 mg/dL, creatinine of 0.91 mg/dL, potassium of 3.9 mmol/L, and sodium of 142 mmol/L. These findings indicated an inflammatory response without significant metabolic disturbance or evidence of organ dysfunction. Radiological Findings Contrast-enhanced computed tomography (CT) presents preoperative findings of the abdomen as illustrated in Fig. 1 . It revealed clustered dilated small bowel loops in the right upper quadrant forming a sac-like mass. There was abnormal crowding and engorgement of mesenteric vessels with a whorled configuration, suggestive of partial small bowel rotation. Proximal small bowel dilatation with distal collapse was observed, consistent with mechanical small bowel obstruction. Inflammatory changes involving the second part of the duodenum were also noted. Importantly, there were no radiological signs of bowel ischemia, necrosis, or perforation. Based on the imaging findings and clinical presentation, a diagnosis of right paraduodenal hernia causing acute small bowel obstruction was established, and the patient was prepared for urgent surgical intervention. Surgical Management and Postoperative Course Postoperative CT illustrated in Fig. 2 demonstrated a notable absence of the retroperitoneal sac and the "whirl sign." The superior mesenteric vessels have returned to their anatomical baseline position, and there is no evidence of residual bowel obstruction or ischemia. Due to the presence of mechanical small bowel obstruction, urgent exploratory laparotomy was performed (Fig. 3 ). Intraoperatively, herniation of jejunal loops through Waldeyer’s fossa was identified, with entrapment of small bowel within a right-sided paraduodenal hernia sac. The herniated bowel appeared viable without evidence of ischemia, necrosis, or perforation. Surgical management included careful reduction of the herniated bowel loops, meticulous identification and preservation of the superior mesenteric vessels, and primary closure of the hernia defect using non-absorbable sutures (Prolene 2 − 0). The procedure was completed without intraoperative complications. The postoperative course was uneventful. A follow-up contrast-enhanced CT scan performed two days after surgery demonstrated successful reduction of the hernia with no residual bowel obstruction and no radiological evidence of postoperative complications. The patient tolerated oral intake, remained hemodynamically stable, and recovered well. He was discharged on the third postoperative day in good general condition. DISCUSSION Right paraduodenal hernias result from incomplete midgut rotation during embryogenesis, leading to the formation of a peritoneal defect through which small bowel loops herniate into abnormal retroperitoneal spaces [ 6 ]. Herniation occurs through Waldeyer’s fossa, located posterior to the superior mesenteric vessels. Although left paraduodenal hernias are more commonly reported, right-sided hernias are considered rarer but are associated with a higher risk of volvulus and vascular compromise due to their anatomical relationship with mesenteric vessels [ 7 ]. Clinical presentation is highly variable. Patients may remain asymptomatic for years or experience intermittent postprandial pain, nausea, bloating, or chronic dyspepsia. In our patient, symptoms persisted for three years and were misdiagnosed as peptic ulcer disease, illustrating the diagnostic challenge frequently encountered in internal hernias [ 8 ]. CT imaging plays a critical role in diagnosis. Characteristic findings include clustered small bowel loops in an abnormal location, encapsulation of bowel segments, displacement of mesenteric vessels, and the “whirl sign” indicating torsion [ 9 ]. In our case, CT imaging provided a definitive preoperative diagnosis and guided timely surgical intervention. Laboratory findings are usually nonspecific. Mild leukocytosis, as observed in our patient (WBC 16.7), may reflect inflammatory stress due to obstruction. Normal renal function and stable electrolytes indicated that the patient had not yet developed severe dehydration or metabolic complications. Definitive treatment is surgical. Options include reduction of herniated bowel loops and either closure or widening of the hernia defect. Care must be taken to protect the superior mesenteric vessels during repair [ 10 ]. Minimally invasive laparoscopic repair has been reported with favorable outcomes in selected stable patients [ 11 ]. Early surgical intervention prevents progression to strangulation, bowel ischemia, or perforation. Delayed treatment significantly increases morbidity and mortality [ 12 – 15 ]. In our case, primary closure with non-absorbable sutures resulted in complete symptom resolution and an excellent postoperative outcome. This case emphasizes the importance of considering internal hernias in patients with recurrent unexplained abdominal pain and no history of prior abdominal surgery. Increased awareness among clinicians and radiologists is essential to avoid misdiagnosis. CONCLUSION Right paraduodenal hernia is a rare but clinically significant cause of small bowel obstruction. Because symptoms are often chronic and nonspecific, diagnosis is frequently delayed. CT imaging is essential for early recognition, and surgical repair remains the definitive treatment. Prompt intervention leads to excellent clinical outcomes and prevents life-threatening complications. Abbreviations CT Computed Tomography PDH Paraduodenal Hernia PDHs Paraduodenal Hernias SBO Small Bowel Obstruction WBC White Blood Cell mmHg Millimeters of Mercury mg/dL Milligrams per Deciliter mmol/L Millimoles per Liter Declarations Ethics approval and consent to participate Ethical approval for this case report was obtained from the appropriate institutional review board at Shifa Medical Complex and Faculty of Medicine at the Islamic University of Gaza in accordance with local research and publication guidelines. The study was conducted in accordance with the ethical principles of the Declaration of Helsinki. All clinical information was handled confidentially, and patient identity was fully protected throughout the preparation of this report. Consent for publication Written informed consent for publication of the clinical details and accompanying images was obtained from the patient. The patient was informed about the purpose of the publication, and all reasonable efforts have been made to ensure that no identifying information is disclosed. Availability of data and materials Data are available upon reasonable request Competing Interest Authors have no conflict of interest Funding None Authors’ contribution Karam Alslaibi and Ibrahim Alnajjar were responsible for collecting the clinical data and patient information related to the case. Tayseer Afifi drafted and wrote the case report manuscript. All authors reviewed, revised, and approved the final version of the manuscript for publication. Acknowledgment Not applicable References Xu H, Nie N, Kong F, Zhong B. Large left paraduodenal hernia with intestinal ischemia: a case report and literature review. J Int Med Res. 2020;48:300060520955040. Hassani KI, Aggouri Y, Laalim SA, Toughrai I, Mazaz K. Left paraduodenal hernia: a rare cause of acute abdomen. Pan Afr Med J. 2014;17:230. Moshref LH, Alqahtani SH, Majeed ZA, Miro J. Left paraduodenal hernia: a rare cause of recurrent abdominal pain: case report. Pan Afr Med J. 2021;40:135. Schizas D, Apostolou K, Krivan S, et al. Paraduodenal hernias: a systematic review of the literature. Hernia. 2019;23:1187–97. Newsom BD, Kukora JS. Congenital and acquired internal hernias: unusual causes of small bowel obstruction. Am J Surg. 1986;152:279–85. Manojlović D, Čekić N, Palinkaš M. Left paraduodenal hernia - a diagnostic challenge: case report. Int J Surg Case Rep. 2021;85:106138. Ghahremani GG. Internal abdominal hernias. Surg Clin North Am. 1984;64:393–406. Agha RA, Franchi T, Sohrabi C, Mathew G, Kerwan A. The SCARE 2020 guideline: updating consensus surgical case report (SCARE) guidelines. Int J Surg. 2020;84:226–30. Manji R, Warnock GL. Left paraduodenal hernia: an unusual cause of small-bowel obstruction. Can J Surg. 2001;44:455–7. Blachar A, Federle MP, Dodson SF. Internal hernia: clinical and imaging findings in 17 patients with emphasis on CT criteria. Radiology. 2001;218:68–74. Shadhu K, Ramlagun D, Ping X. Para-duodenal hernia: a report of five cases and review of literature. BMC Surg. 2018;18:32. Takeyama N, Gokan T, Ohgiya Y, et al. CT of internal hernias. Radiographics. 2005;25:997–1015. Lanzetta MM, Masserelli A, Addeo G, et al. Internal hernias: a difficult diagnostic challenge. Review of CT signs and clinical findings. Acta Biomed. 2019;90:20–37. Khalaileh A, Schlager A, Bala M, Abu-Gazala S, Elazary R, Rivkind AI, Mintz Y. Left laparoscopic paraduodenal hernia repair. Surg Endosc. 2010;24:1486–9. Jeong GA, Cho GS, Kim HC, Shin EJ, Song OP. Laparoscopic repair of paraduodenal hernia: comparison with conventional open repair. Surg Laparosc Endosc Percutan Tech. 2008;18:611–5. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 22 Apr, 2026 Reviewers invited by journal 17 Apr, 2026 Editor assigned by journal 18 Mar, 2026 Submission checks completed at journal 18 Mar, 2026 First submitted to journal 14 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9122376","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":627883624,"identity":"e5fba49b-2242-46a5-8ffc-434c39a2963a","order_by":0,"name":"Karam Alslaibi","email":"","orcid":"","institution":"Shifa Medical Complex","correspondingAuthor":false,"prefix":"","firstName":"Karam","middleName":"","lastName":"Alslaibi","suffix":""},{"id":627883625,"identity":"c0b25f99-df73-44f8-b8ac-5035e6d8902d","order_by":1,"name":"Ibrahim Alnajjar","email":"","orcid":"","institution":"European Gaza Hospital","correspondingAuthor":false,"prefix":"","firstName":"Ibrahim","middleName":"","lastName":"Alnajjar","suffix":""},{"id":627883627,"identity":"e0fd953d-9d56-4598-ab69-6111a1c4b514","order_by":2,"name":"Tayseer Afifi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/UlEQVRIiWNgGAWjYDAC5oMNHxLgvAqQCHMDfi1siY0zEhgMoLwzIC2MhLQkMM5ggGlhbAOT+LXwtzE3Njxg+CNvcP7wwceV82qj+duBWn5UbMOpReIYY2MD0GGGG26kJRue3XY8d8ZhxgbGnjO3cVtzv7H9AVAL44YbPGaSjduO5TYAtTAztuHWIg+1xX7D+fPffzbOOZY7n5AWA6iWxA0HctiAzJrcDYS0GIK1GBgnz7yRZizZcOxA7kagloP4/CJ3jP1h448KOdu+84cffmyoqcudBwy6Bz8q8Hgf4jwGBoUDYNZhMHmAgHoIkG8AU3VEKR4Fo2AUjIKRBQB9LWL+H0Y3ogAAAABJRU5ErkJggg==","orcid":"","institution":"Islamic University of Gaza","correspondingAuthor":true,"prefix":"","firstName":"Tayseer","middleName":"","lastName":"Afifi","suffix":""}],"badges":[],"createdAt":"2026-03-14 12:08:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9122376/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9122376/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":107870566,"identity":"d48a61f4-94c6-4b6e-955b-306ab74d5700","added_by":"auto","created_at":"2026-04-27 07:39:56","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":547591,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003e\u003cstrong\u003ePreoperative contrast-enhanced CT scans in (A) coronal and (B, C) axial planes. The images reveal a cluster of dilated small bowel loops localized in the right upper quadrant, lateral and inferior to the descending duodenum. There is a characteristic \"whirl sign\" of the mesenteric vessels and displacement of the superior mesenteric artery (SMA) and vein (SMV) anteriorly, consistent with a right paraduodenal hernia through the fossa of Waldeyer.\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-9122376/v1/56b5500c04ec1649cdf43421.png"},{"id":107839355,"identity":"17f387c5-a9f6-4133-8190-0768720326be","added_by":"auto","created_at":"2026-04-26 17:19:22","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":759165,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003e\u003cstrong\u003eAxial post-operative CT scans demonstrating the successful surgical repair of the right paraduodenal hernia. The previously clustered small bowel loops are now normally distributed throughout the abdominal cavity. There is a notable absence of the retroperitoneal sac and the \"whirl sign.\" The superior mesenteric vessels have returned to their anatomical baseline position, and there is no evidence of residual bowel obstruction or ischemia.\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-9122376/v1/656f185b15e82a59e1b6b1e0.png"},{"id":107870410,"identity":"9649af94-e2e6-4bdf-88de-30386a5d4f9f","added_by":"auto","created_at":"2026-04-27 07:39:36","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":789466,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003e\u003cstrong\u003eIntraoperative view during exploratory laparotomy demonstrating a right paraduodenal hernia (RPH). The small bowel is seen herniating into the fossa of Waldeyer, situated behind the root of the mesentery. Note the entrapment of the proximal jejunal loops within the retroperitoneal sac.\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-9122376/v1/cb3464af29d44fb62d9c6c7d.png"},{"id":107872308,"identity":"afa055d1-bcaa-4181-b69e-c5845efd4d9a","added_by":"auto","created_at":"2026-04-27 07:56:44","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2246984,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9122376/v1/91cb1417-69b9-47e0-859b-2922916440bd.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"When Chronic Abdominal Pain Turns Acute: A Case of Right Paraduodenal Hernia","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eParaduodenal hernias (PDHs) are rare congenital internal hernias caused by abnormal rotation and fixation of the midgut during embryological development. They account for approximately 50\u0026ndash;55% of all internal hernias and are classified into left-sided (Landzert\u0026rsquo;s fossa) and right-sided (Waldeyer\u0026rsquo;s fossa) variants, with the right type being less common [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eInternal hernias represent an uncommon but clinically significant cause of small bowel obstruction, particularly in patients without prior abdominal surgery. The incidence of internal hernias in the general population is low; however, they account for a meaningful proportion of unexplained bowel obstruction cases [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Delayed diagnosis is common because symptoms are often intermittent, nonspecific, and mimic other gastrointestinal disorders such as peptic ulcer disease, biliary colic, or functional dyspepsia [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eComputed tomography (CT) is the imaging modality of choice and typically demonstrates clustered small bowel loops, abnormal mesenteric vessel orientation, and the characteristic \u0026ldquo;whirl sign\u0026rdquo; in cases complicated by volvulus [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Early recognition is crucial because surgical treatment is the definitive management and prevents life-threatening complications.\u003c/p\u003e \u003cp\u003eWe present a rare case of right paraduodenal hernia presenting as acute small bowel obstruction in a patient with a three-year history of recurrent abdominal pain previously misdiagnosed as peptic ulcer disease.\u003c/p\u003e"},{"header":"CASE PRESENTATION","content":"\u003cp\u003eClinical Presentation\u003c/p\u003e \u003cp\u003eA 43-year-old male patient with no known chronic medical illnesses and no previous surgical history presented to the emergency department with acute abdominal pain of three days\u0026rsquo; duration. The pain was colicky in nature, progressively worsening, and radiated to the right upper quadrant. It was associated with repeated episodes of non-bilious vomiting and constipation, suggestive of mechanical intestinal obstruction. The patient denied any history of abdominal trauma, prior abdominal surgery, or similar acute episodes requiring hospitalization.\u003c/p\u003e \u003cp\u003ePhysical Examination\u003c/p\u003e \u003cp\u003eOn examination, the patient was hemodynamically stable with a blood pressure of 115/75 mmHg, a pulse rate of 105 beats per minute, and was afebrile. Abdominal examination revealed a soft but distended abdomen with localized tenderness and mild guarding in the right upper quadrant. Bowel sounds were diminished. No palpable masses, rebound tenderness, or signs of generalized peritonitis were detected.\u003c/p\u003e \u003cp\u003ePast Medical History\u003c/p\u003e \u003cp\u003eA detailed medical history revealed that the patient had experienced recurrent upper abdominal pain for approximately three years prior to this presentation. The episodes were intermittent and had been managed conservatively under a presumed diagnosis of peptic ulcer disease without significant clinical improvement despite medical therapy. There was no associated history of gastrointestinal bleeding, significant weight loss, chronic diarrhea, or other symptoms suggestive of inflammatory bowel disease.\u003c/p\u003e \u003cp\u003eLaboratory Investigations\u003c/p\u003e \u003cp\u003eLaboratory investigations demonstrated mild leukocytosis with a white blood cell count of 16.7 \u0026times;10⁹/L. Hemoglobin was 12.1 g/dL and platelet count was 270 \u0026times;10⁹/L. Biochemical parameters showed a random blood sugar of 112 mg/dL, urea level of 62 mg/dL, creatinine of 0.91 mg/dL, potassium of 3.9 mmol/L, and sodium of 142 mmol/L. These findings indicated an inflammatory response without significant metabolic disturbance or evidence of organ dysfunction.\u003c/p\u003e \u003cp\u003eRadiological Findings\u003c/p\u003e \u003cp\u003eContrast-enhanced computed tomography (CT) presents preoperative findings of the abdomen as illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. It revealed clustered dilated small bowel loops in the right upper quadrant forming a sac-like mass. There was abnormal crowding and engorgement of mesenteric vessels with a whorled configuration, suggestive of partial small bowel rotation. Proximal small bowel dilatation with distal collapse was observed, consistent with mechanical small bowel obstruction. Inflammatory changes involving the second part of the duodenum were also noted. Importantly, there were no radiological signs of bowel ischemia, necrosis, or perforation. Based on the imaging findings and clinical presentation, a diagnosis of right paraduodenal hernia causing acute small bowel obstruction was established, and the patient was prepared for urgent surgical intervention.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eSurgical Management and Postoperative Course\u003c/p\u003e \u003cp\u003ePostoperative CT illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e demonstrated a notable absence of the retroperitoneal sac and the \"whirl sign.\" The superior mesenteric vessels have returned to their anatomical baseline position, and there is no evidence of residual bowel obstruction or ischemia. Due to the presence of mechanical small bowel obstruction, urgent exploratory laparotomy was performed (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Intraoperatively, herniation of jejunal loops through Waldeyer\u0026rsquo;s fossa was identified, with entrapment of small bowel within a right-sided paraduodenal hernia sac. The herniated bowel appeared viable without evidence of ischemia, necrosis, or perforation. Surgical management included careful reduction of the herniated bowel loops, meticulous identification and preservation of the superior mesenteric vessels, and primary closure of the hernia defect using non-absorbable sutures (Prolene 2\u0026thinsp;\u0026minus;\u0026thinsp;0). The procedure was completed without intraoperative complications.\u003c/p\u003e \u003cp\u003eThe postoperative course was uneventful. A follow-up contrast-enhanced CT scan performed two days after surgery demonstrated successful reduction of the hernia with no residual bowel obstruction and no radiological evidence of postoperative complications. The patient tolerated oral intake, remained hemodynamically stable, and recovered well. He was discharged on the third postoperative day in good general condition.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eRight paraduodenal hernias result from incomplete midgut rotation during embryogenesis, leading to the formation of a peritoneal defect through which small bowel loops herniate into abnormal retroperitoneal spaces [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Herniation occurs through Waldeyer\u0026rsquo;s fossa, located posterior to the superior mesenteric vessels.\u003c/p\u003e \u003cp\u003eAlthough left paraduodenal hernias are more commonly reported, right-sided hernias are considered rarer but are associated with a higher risk of volvulus and vascular compromise due to their anatomical relationship with mesenteric vessels [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eClinical presentation is highly variable. Patients may remain asymptomatic for years or experience intermittent postprandial pain, nausea, bloating, or chronic dyspepsia. In our patient, symptoms persisted for three years and were misdiagnosed as peptic ulcer disease, illustrating the diagnostic challenge frequently encountered in internal hernias [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eCT imaging plays a critical role in diagnosis. Characteristic findings include clustered small bowel loops in an abnormal location, encapsulation of bowel segments, displacement of mesenteric vessels, and the \u0026ldquo;whirl sign\u0026rdquo; indicating torsion [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. In our case, CT imaging provided a definitive preoperative diagnosis and guided timely surgical intervention.\u003c/p\u003e \u003cp\u003eLaboratory findings are usually nonspecific. Mild leukocytosis, as observed in our patient (WBC 16.7), may reflect inflammatory stress due to obstruction. Normal renal function and stable electrolytes indicated that the patient had not yet developed severe dehydration or metabolic complications.\u003c/p\u003e \u003cp\u003eDefinitive treatment is surgical. Options include reduction of herniated bowel loops and either closure or widening of the hernia defect. Care must be taken to protect the superior mesenteric vessels during repair [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Minimally invasive laparoscopic repair has been reported with favorable outcomes in selected stable patients [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eEarly surgical intervention prevents progression to strangulation, bowel ischemia, or perforation. Delayed treatment significantly increases morbidity and mortality [\u003cspan additionalcitationids=\"CR13 CR14\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. In our case, primary closure with non-absorbable sutures resulted in complete symptom resolution and an excellent postoperative outcome.\u003c/p\u003e \u003cp\u003eThis case emphasizes the importance of considering internal hernias in patients with recurrent unexplained abdominal pain and no history of prior abdominal surgery. Increased awareness among clinicians and radiologists is essential to avoid misdiagnosis.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eRight paraduodenal hernia is a rare but clinically significant cause of small bowel obstruction. Because symptoms are often chronic and nonspecific, diagnosis is frequently delayed. CT imaging is essential for early recognition, and surgical repair remains the definitive treatment. Prompt intervention leads to excellent clinical outcomes and prevents life-threatening complications.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u003cb\u003eCT\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eComputed Tomography\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u003cb\u003ePDH\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eParaduodenal Hernia\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u003cb\u003ePDHs\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eParaduodenal Hernias\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u003cb\u003eSBO\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eSmall Bowel Obstruction\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u003cb\u003eWBC\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eWhite Blood Cell\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u003cb\u003emmHg\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMillimeters of Mercury\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u003cb\u003emg/dL\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMilligrams per Deciliter\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u003cb\u003emmol/L\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMillimoles per Liter\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEthical approval for this case report was obtained from the appropriate institutional review board at Shifa Medical Complex and Faculty of Medicine at the Islamic University of Gaza in accordance with local research and publication guidelines. The study was conducted in accordance with the ethical principles of the Declaration of Helsinki. All clinical information was handled confidentially, and patient identity was fully protected throughout the preparation of this report.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent for publication of the clinical details and accompanying images was obtained from the patient. The patient was informed about the purpose of the publication, and all reasonable efforts have been made to ensure that no identifying information is disclosed.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData are available upon reasonable request\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting Interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAuthors have no conflict of interest\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contribution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eKaram Alslaibi and Ibrahim Alnajjar were responsible for collecting the clinical data and patient information related to the case. Tayseer Afifi drafted and wrote the case report manuscript. All authors reviewed, revised, and approved the final version of the manuscript for publication.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgment\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eXu H, Nie N, Kong F, Zhong B. Large left paraduodenal hernia with intestinal ischemia: a case report and literature review. J Int Med Res. 2020;48:300060520955040.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHassani KI, Aggouri Y, Laalim SA, Toughrai I, Mazaz K. Left paraduodenal hernia: a rare cause of acute abdomen. Pan Afr Med J. 2014;17:230.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMoshref LH, Alqahtani SH, Majeed ZA, Miro J. Left paraduodenal hernia: a rare cause of recurrent abdominal pain: case report. Pan Afr Med J. 2021;40:135.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSchizas D, Apostolou K, Krivan S, et al. Paraduodenal hernias: a systematic review of the literature. Hernia. 2019;23:1187\u0026ndash;97.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNewsom BD, Kukora JS. Congenital and acquired internal hernias: unusual causes of small bowel obstruction. Am J Surg. 1986;152:279\u0026ndash;85.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eManojlović D, Čekić N, Palinkaš M. Left paraduodenal hernia - a diagnostic challenge: case report. Int J Surg Case Rep. 2021;85:106138.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGhahremani GG. Internal abdominal hernias. Surg Clin North Am. 1984;64:393\u0026ndash;406.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAgha RA, Franchi T, Sohrabi C, Mathew G, Kerwan A. The SCARE 2020 guideline: updating consensus surgical case report (SCARE) guidelines. Int J Surg. 2020;84:226\u0026ndash;30.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eManji R, Warnock GL. Left paraduodenal hernia: an unusual cause of small-bowel obstruction. Can J Surg. 2001;44:455\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBlachar A, Federle MP, Dodson SF. Internal hernia: clinical and imaging findings in 17 patients with emphasis on CT criteria. Radiology. 2001;218:68\u0026ndash;74.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eShadhu K, Ramlagun D, Ping X. Para-duodenal hernia: a report of five cases and review of literature. BMC Surg. 2018;18:32.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTakeyama N, Gokan T, Ohgiya Y, et al. CT of internal hernias. Radiographics. 2005;25:997\u0026ndash;1015.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLanzetta MM, Masserelli A, Addeo G, et al. Internal hernias: a difficult diagnostic challenge. Review of CT signs and clinical findings. Acta Biomed. 2019;90:20\u0026ndash;37.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKhalaileh A, Schlager A, Bala M, Abu-Gazala S, Elazary R, Rivkind AI, Mintz Y. Left laparoscopic paraduodenal hernia repair. Surg Endosc. 2010;24:1486\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJeong GA, Cho GS, Kim HC, Shin EJ, Song OP. Laparoscopic repair of paraduodenal hernia: comparison with conventional open repair. Surg Laparosc Endosc Percutan Tech. 2008;18:611\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"international-journal-of-emergency-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ijem","sideBox":"Learn more about [International Journal of Emergency Medicine](https://intjem.biomedcentral.com/)","snPcode":"12245","submissionUrl":"https://submission.nature.com/new-submission/12245/3","title":"International Journal of Emergency Medicine","twitterHandle":"@IntJEmergMed","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Paraduodenal hernia, Internal hernia, Small bowel obstruction, Waldeyer’s fossa, Case report","lastPublishedDoi":"10.21203/rs.3.rs-9122376/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9122376/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eParaduodenal hernias (PDHs) are rare congenital internal hernias resulting from abnormal midgut rotation during embryologic development. They represent the most common type of internal hernia and are an uncommon but important cause of small bowel obstruction. Because clinical manifestations are often nonspecific and intermittent, diagnosis is frequently delayed, increasing the risk of strangulation and ischemia.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCase Presentation:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe report the case of a 43-year-old male with no significant medical or surgical history who presented with acute abdominal pain and a long-standing history of recurrent upper abdominal pain previously misdiagnosed as peptic ulcer disease. Contrast-enhanced computed tomography (CT) revealed a right paraduodenal hernia with partial small bowel rotation and features consistent with intestinal obstruction. The patient underwent urgent exploratory laparotomy, confirming herniation of jejunal loops through Waldeyer’s fossa. Surgical reduction and closure of the hernia defect were performed. The postoperative course was uneventful.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eRight paraduodenal hernia should be considered in patients with recurrent unexplained abdominal pain without prior abdominal surgery. Early CT imaging and timely surgical intervention are essential to prevent complications.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical Trial Number: Not Applicable\u003c/strong\u003e\u003c/p\u003e","manuscriptTitle":"When Chronic Abdominal Pain Turns Acute: A Case of Right Paraduodenal Hernia","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-26 17:19:18","doi":"10.21203/rs.3.rs-9122376/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"155491662264874629090830954467968483684","date":"2026-04-22T15:47:47+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-17T14:27:34+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-18T12:42:47+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-18T12:41:51+00:00","index":"","fulltext":""},{"type":"submitted","content":"International Journal of Emergency Medicine","date":"2026-03-14T11:53:37+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"international-journal-of-emergency-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ijem","sideBox":"Learn more about [International Journal of Emergency Medicine](https://intjem.biomedcentral.com/)","snPcode":"12245","submissionUrl":"https://submission.nature.com/new-submission/12245/3","title":"International Journal of Emergency Medicine","twitterHandle":"@IntJEmergMed","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"e1487583-2d26-4ede-a5c3-2d336af6f27d","owner":[],"postedDate":"April 26th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-04-26T17:19:18+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-26 17:19:18","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9122376","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9122376","identity":"rs-9122376","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}