Malignant lymphoma of jejunum with common variable hypogammaglobulinemia and diffuse nodular hyperplasia of the small intestine. A case study and literature review

Immunogenetics of gastrointestinal cancers: A systematic review and retrospective survey of inborn errors of immunity in humans

BACKGROUND AND AIM

Humans with inborn errors of immunity (IEI), or primary immunodeficiencies, may be associated with a potential risk factor for early-onset gastrointestinal (GI) cancer.

METHODS

We systematically reviewed all cases with clinical diagnoses of both an IEI and a GI cancer in three databases (MEDLINE, SCOPUS, and EMBASE). In total, 76 publications satisfying our inclusion criteria were identified, and data for 149 cases were analyzed. We also searched our institutional cancer registry for such cases.

RESULTS

We identified 149 patients with both an IEI and a GI cancer, 95 presented gastric cancer, 13 small bowel cancer, 35 colorectal cancer, and 6 had an unspecified cancer or cancer at another site. Gastric and colon adenocarcinomas were the most common. For both gastric and colorectal cancers, age at onset was significantly earlier in patients with IEIs than in the general population, based on the SEER database. Common variable immunodeficiency (CVID) was the most common IEI associated with gastrointestinal cancer. About 12% of patients had molecular genetic diagnoses, the three most frequently implicated genes being ATM, CARMIL2, and CTLA4. Impaired humoral immunity and Epstein-Barr virus (EBV) infection were frequently reported as factors potentially underlying early-onset GI cancers in patients with IEIs. We identified one patient with CVID and early-onset gastric adenocarcinoma, recurrent diarrhea, and gastrointestinal CMV infection from a retrospective survey.

CONCLUSION

Patients with IEIs should be considered at risk of early-onset GI cancers and should therefore undergo cancer screening at an earlier age.

Long-term Prognosis of Localized Lymphoid Hyperplasia of the Rectum

Background/Aims

Although localized lymphoid hyperplasia (LLH) of the rectum is occasionally observed, its clinical implications are unclear. This study aimed to investigate the clinical course and significance of LLH of the rectum.

Methods

We identified 65 patients diagnosed with LLH of the rectum using a histopathologic examination and who received follow-up endoscopies between January 2009 and June 2015. Patients with a history of inflammatory bowel disease, lymphoma, familial adenomatous polyposis, or uncontrolled malignancy and patients who underwent scar biopsy after endoscopic resection or surgery were excluded. Endoscopic findings and clinical courses were analyzed.

Results

During the median follow-up of 31 months (interquartile range, 19 to 40 months), 81.5% (53/65) of LLHs of the rectum were resolved. Clinically significant diseases, including ulcerative colitis (UC, n=5) and mucosa-associated lymphoid tissue (MALT) lymphoma (n=1), were diagnosed in 9.2% of patients (6/65). The other six patients showed no significant changes in the lesion (n=3) or a waxing and waning appearance (n=3). According to endoscopic findings, all of the 47 polypoid types showed resolution or waxing and waning patterns. Five of the 11 nodular types (45.5%) developed into UC. One of the seven submucosal tumor (SMT)-like types (14.3%) developed into MALT lymphoma.

Conclusions

LLH of the rectum with persistent symptoms or the endoscopic appearance of the nodular or SMT-like type may lead to clinically significant disease. Risk stratification according to endoscopic findings and careful surveillance are required for these lesions.

Primary Humoral Immune Deficiencies: Overlooked Mimickers of Chronic Immune-Mediated Gastrointestinal Diseases in Adults

In recent years, the incidence of immune-mediated gastrointestinal disorders, including celiac disease (CeD) and inflammatory bowel disease (IBD), is increasingly growing worldwide. This generates a need to elucidate the conditions that may compromise the diagnosis and treatment of such gastrointestinal disorders. It is well established that primary immunodeficiencies (PIDs) exhibit gastrointestinal manifestations and mimic other diseases, including CeD and IBD. PIDs are often considered pediatric ailments, whereas between 25 and 45% of PIDs are diagnosed in adults. The most common PIDs in adults are the selective immunoglobulin A deficiency (SIgAD) and the common variable immunodeficiency (CVID). A trend to autoimmunity occurs, while gastrointestinal disorders are common in both diseases. Besides, the occurrence of CeD and IBD in SIgAD/CVID patients is significantly higher than in the general population. However, some differences concerning diagnostics and management between enteropathy/colitis in PIDs, as compared to idiopathic forms of CeD/IBD, have been described. There is an ongoing discussion whether CeD and IBD in CVID patients should be considered a true CeD and IBD or just CeD-like and IBD-like diseases. This review addresses the current state of the art of the most common primary immunodeficiencies in adults and co-occurring CeD and IBD.

Gastrointestinal Disorders Associated with Primary Immunodeficiency Diseases

There are now 354 inborn errors of immunity (primary immunodeficiency diseases (PIDDs)) with 344 distinct molecular etiologies reported according to the International Union of Immunological Sciences (IUIS) (Clin Gastroenterol Hepatol 11: p. 1050-63, 2013, Semin Gastrointest Dis 8: p. 22-32, 1997, J Clin Immunol 38: p. 96-128, 2018). Using the IUIS document as a reference and cross-checking PubMed ( www.ncbi.nlm.nih.pubmed.gov ), we found that approximately one third of the 354 diseases of impaired immunity have a gastrointestinal component [J Clin Immunol 38: p. 96-128, 2018]. Often, the gastrointestinal symptomatology and pathology is the heralding sign of a PIDD; therefore, it is important to recognize patterns of disease which may manifest along the gastrointestinal tract as a more global derangement of immune function. As such, holistic consideration of immunity is warranted in patients with clinically significant gastrointestinal disease. Here, we discuss the manifold presentations and GI-specific complications of PIDDs which could lead patients to seek advice from a variety of clinician specialists. Often, patients with these medical problems will engage general pediatricians, surgeons, gastroenterologists, rheumatologists, and clinical immunologists among others. Following delineation of the presenting concern, accurate and often molecular diagnosis is imperative and a multi-disciplinary approach warranted for optimal management. In this review, we will summarize the current state of understanding of PIDD gastrointestinal disease involvement. We will do so by focusing upon gastrointestinal disease categories (i.e., inflammatory, diarrhea, nodular lymphoid hyperplasia, liver/biliary tract, structural disease, and oncologic disease) with an intent to aid the healthcare provider who may encounter a patient with an as-yet undiagnosed PIDD who presents initially with a gastrointestinal symptom, sign, or problem.

Primary Immunodeficiencies: Diseases of Children and Adults - A Review

Primary immunodeficiencies (PIDs) belong to a group of rare congenital diseases occurring all over the world that may be seen in both children and adults. In most cases, genetic predispositions are already known. As shown in this review, genetic abnormalities may be related to dysfunction of the immune system, which manifests itself as recurrent infections, increased risk of cancer, and autoimmune diseases. This article reviews the various forms of PIDs, including their characterization, management strategies, and complications. Novel aspects of the diagnostics and monitoring of PIDs are presented.

Primary Immunodeficiency and the Gut

This article presents the most common gastrointestinal, hepatic, and pancreatic manifestations of the primary immunodeficiency diseases, including the appropriate laboratory testing, endoscopic evaluation, and recommendations for further management.

A Systematic Review on Predisposition to Lymphoid (B and T cell) Neoplasias in Patients With Primary Immunodeficiencies and Immune Dysregulatory Disorders (Inborn Errors of Immunity)

Primary immunodeficiencies and immune dysregulatory disorders (PIDDs; now referred to as inborn errors in immunity) are rare disorders with a prevalence of 41. 4 or 50.5 per 100,000 persons (1). The incidence of malignancy in PIDD patents is the second-highest cause of death in children as well as adults, after infection, and is higher in certain PIDDs compared to others. We performed a systematic review of the literature to identify reports of B cell and T cell neoplasias in PIDDs and clustered them based on their classification in the IUIS schema. As would be expected, higher susceptibility to malignancies are typically reported in patients with Common Variable Immunodeficiency (CVID), combined immunodeficiencies affecting cellular immunity, in particular, DNA repair defects, or in the context of impaired immune regulatory control. There is not much evidence of increased risk for cancer in patients with innate immune defects, indicating that not all types of infection or genetic susceptibility predispose equally to cancer risk. Viral infections, in particular EBV, HHV and HPV, have been shown to increase susceptibility to developing cancer, but also patients with defects in immune regulation, such as Autoimmune Lymphoproliferative Syndrome (ALPS), activated p110delta syndrome (APDS type 1) and IL-10 receptor deficiency among others have a higher incidence of neoplastic disease, particularly lymphomas. In fact, lymphomas account for two-thirds of all malignancies reported in PIDD patients (2), with either a combined immunodeficiency or DNA repair defect predominating as the underlying immune defect in one registry, or antibody deficiencies in another (3). The vast majority of lymphomas reported in the context of PIDDs are B cell lymphomas, though T cell lymphomas have been reported in a few studies, and tend to largely be associated with chromosomal breakage disorders (4) or Cartilage Hair Hypoplasia (5). There appears to be a much higher prevalence of T cell lymphomas in patients with secondary immunodeficiencies (6), though this could reflect treatment bias. We reviewed the literature and summarized the reports of B and T cell lymphoma in PIDD patients to survey the current state of knowledge in this area.

Gastrointestinal Disease in Patients with Common Variable Immunodeficiency: A Retrospective Observational Study

Background

Gastrointestinal (GI) symptoms are common among patients with common variable immunodeficiency disorder (CVID) yet remain poorly understood.

Aims

The aim of this study was to characterize the demographic, clinical, endoscopic and histologic features of patients with CVID and GI symptoms.

Methods

We conducted a retrospective observational study of all patients with CVID at a large Canadian tertiary care centre between January 2000 and May 2018.

Results

We included 95 patients with CVID. The mean age of patients at the time of CVID diagnosis was 38.2(±16.0). Fifty-three (56%) patients were female. Sixty-four (67%) patients had GI symptoms, with a mean age of onset for GI symptoms of 43.4(±15.1) years. The most common symptoms were bowel movement changes (n = 55 [58%]) and abdominal pain (n = 44 [46%]). Patients with GI symptoms were more likely to have anemia (n = 23 [36%] versus n = 3 [10%], P = 0.0129), iron deficiency (n = 16 [25%] versus n = 2 [7%], P = 0.0481), and have received GI antibiotics (n = 37 [58%] versus n = 0, P < 0.0001) and proton pump inhibitors for reflux (n = 24 [38%] versus n = 3 [10%], P = 0.0067). The most common GI infections were Giardia lamblia (n = 14 [15%]) and Clostridium difficile (n = 4 [4%]). Forty-three (45%) patients with GI symptoms underwent colonoscopy, esophagogastroduodenoscopy or both. The most common findings were inflammation, nodular lymphoid hyperplasia, reduced plasma cells and increased intraepithelial lymphocytes.

Conclusions

This is the largest study on CVID patients in a North American setting. The majority of patients experienced GI symptoms. Future studies should study response to treatment for GI disease among patients with CVID.

Chronic Diarrhea in Common Variable Immunodeficiency: a Case Series and Review of the Literature

Common variable immunodeficiency (CVID) is a primary immunodeficiency characterized by reduced immunoglobulin serum levels and absent or impaired antibody production. Clinical manifestations, including infections, inflammatory and autoimmune diseases, and malignancies, also involve various segments of the gastrointestinal tract. Chronic diarrhea is one of the most common gastrointestinal symptoms and may cause a wide spectrum of potentially life-threatening conditions as malabsorption and protein-energy malnutrition. We describe three female CVID adult patients presenting with chronic diarrhea, weight loss, and protein-energy malnutrition due to different underlying conditions. Our review of the literature explores the various gastrointestinal involvements in CVID and points out several histopathological findings proper of the disease, thus highlighting the relevance of the endoscopic and histological assessment in CVID patients presenting with chronic diarrhea.

Common Variable Immunodeficiency with Several Gastrointestinal Manifestations

Common variable immunodeficiency (CVID) is an immunodeficiency disorder with a high incidence of gastrointestinal (GI) manifestations and an increased risk of gastric malignancy. We report a case of a CVID with mild anemia presenting with multiple GI manifestations: gastric low-grade dysplasia (LGD), enteropathy with villous atrophy, refractory Giardia infection, nodular lymphoid hyperplasia, and inflammatory bowel-like disease. The differential diagnosis with celiac sprue could be challenging because of CVID enteropathy with villous flattening. Gastric LGD in a patient with an increased risk for gastric malignancy makes the appropriate surveillance of gastric cancer in CVID challenging.

Clinicopathological and Ileocolonoscopic Characteristics in Patients with Nodular Lymphoid Hyperplasia in the Terminal Ileum

Nodular lymphoid hyperplasia (NLH) in the small intestine is a rare benign lesion, characterized by the presence of multiple small nodules on the surface of the intestine. To define the clinicopathological and colonoscopic characteristics in Chinese patients with ileal NLH, we collected 65 patients with NLH in the terminal ileum from the endoscopic database in our hospital and clinical data from medical records. Histology and immunohistochemical staining were performed in the biopsies. The results demonstrated that the main symptoms included diarrhea (70.8%), abdominal pain (60.0%), hematochezia (46.2%), anemia (40.0%), and hypoproteinemia (21.5%). Enteroscopy revealed multiple, sporadic, granular or round-shaped nodules with diameters between 2 and 5 mm in the terminal ileum. The histology revealed the nodules consisted of mass lymphoid follicles in the lamina propria and submucosa of the terminal ileum. The follicles contained mitotically active germinal centers surrounded by well-defined lymphocyte mantles and composed predominantly of CD20⁺ B cells. The diseases found in patients with NLH included chronic diarrhea, Crohn's disease, ischemic enterocolitis and allergic purpura. The level of hemoglobin in NLH patients who had diarrhea and hematochezia remarkably decreased as compared with those in patients with chronic diarrhea. In conclusion, ileocolonoscopic screening is an important step to find the NLH in terminal ileum patients with diarrhea, abdominal pain, hematochezia, and hypoproteinemia. Histological examination is necessary for the exclusion of malignancy and chronic inflammation.

Nodular lymphoid hyperplasia complicated with ileal Burkitt's lymphoma in an adult patient with selective IgA deficiency

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Burkitt's lymphoma in adults can occur on the basis of nodular lymphoid hyperplasia.

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Nodular lymphoid hyperplasia is associated with selective IgA deficiency.

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Nodular lymphoid hyperplasia associates IgA deficiency with Burkitt's lymphoma.

Introduction

Primary lymphomas of the small intestine are rare. Burkitt's lymphoma (BL) occurs sporadically in adults. Nodular lymphoid hyperplasia (NLH) is a rare disorder characterized by diffuse nodular lesions, which represent hyperplastic lymphoid follicles, and it is often associated with immunodeficiency syndromes.

Presentation of case

We present a 38-year-old male patient in a state of surgical emergency, suspected of Crohn’s disease, who had an unusual combination of NLH and BL of the proximal ileum. Furthermore, retrospectively analyzed documentation revealed selective IgA deficiency.

Discussion

Association between NLH and intestinal lymphomas in patients with immunodeficiency syndromes was indicated before. This case report supports the notion on NLH as a transition state between immunodeficiency and intestinal lymphomas.

Conclusion

This is one of the first case reports which presents the combination of NHL and BL. The awareness of the existence of this rare combination, especially in young adult males, can improve the diagnostic accuracy and the treatment management.

Inflammatory bowel disease-like colitis pathology in a patient with common variable immune deficiency

Common variable immunodeficiency (CVID) can show variant histological patterns in the gastrointestinal system. We present a case of an 11-year-old boy who has been followed up with a diagnosis of CVID since he was 6 months old. He presented with abdominal pain and diarrhoea. Colonoscopic biopsy showed crypt destructive colitis, severe decrease and focal absence of plasma cells. Three months later he suffered from abdominal pain, vomiting and bloody diarrhoea. Macroscopic examination of small intestinal resection material revealed multiple perforation areas, ulcers. Histopathology showed mild-moderate active enteritis with aphthous ulcers, purulent peritonitis, decrease in plasma cells and loss of primary follicles in lymph nodes. Histopathological findings were consistent with inflammatory bowel disease (IBD)-like CVID. Although in 6-10% of patients with CVID an IBD-like presentation is observed, this highly aggressive form is rarely seen. We present this case because of its extraordinary presentation displaying perforating active enteropathy.

Diffuse duodenal nodular lymphoid hyperplasia: a large cohort of patients etiologically related to Helicobacter pylori infection

BACKGROUND

Nodular lymphoid hyperplasia of gastrointestinal tract is a rare disorder, often associated with immunodeficiency syndromes. There are no published reports of its association with Helicobacter pylori infection.

METHODS

From March 2005 till February 2010, we prospectively followed all patients with diffuse duodenal nodular lymphoid hyperplasia (DDNLH). Patients underwent esophagogastroduodenoscopy with targeted biopsies, colonoscopy, and small bowel video capsule endoscopy. Duodenal nodular lesions were graded from 0 to 4 based on their size and density. Patients were screened for celiac sprue (IgA endomysial antibody), immunoglobulin abnormalities (immunoglobulin levels & serum protein electrophoresis), small intestine bacterial overgrowth (lactulose hydrogen breath test), and Helicobacter pylori infection (rapid urease test, and histological examination of gastric biopsies). Patients infected with Helicobacter pylori received sequential antibiotic therapy and eradication of infection was evaluated by 14C urea breath test. Follow up duodenoscopies with biopsies were performed to ascertain resolution of nodular lesions.

RESULTS

Forty patients (Males 23, females 17; mean age ± 1SD 35.6 ± 14.6 years) with DDNLH were studied. Patients presented with epigastric pain, vomiting, and weight loss. Esophagogastroduodenoscopy showed diffuse nodular lesions (size varying from 2 to 5 mm or more) of varying grades (mean score ± 1SD 2.70 ± 0.84) involving postbulbar duodenum. Video capsule endoscopies revealed nodular disease exclusively limited to duodenum. None of the patients had immunoglobulin deficiency or small intestine bacterial overgrowth or positive IgA endomysial antibodies. All patients were infected with Helicobacter pylori infection. Sequential antibiotic therapy eradicated Helicobacter pylori infection in 26 patients. Follow up duodenoscopies in these patients showed significant reduction of duodenal nodular lesions score (2.69 ± 0.79 to 1.50 ± 1.10; p < 0.001). Nodular lesions showed complete resolution in 5 patients and significant resolution in remaining 21 patients. Patients with resistant Helicobacter pylori infection showed no significant reduction of nodular lesions score (2.71 ± 0.96 to 2.64 ± 1.15; p = 0.58). Nodules partially regressed in score in 2 patients, showed no interval change in 10 patients and progressed in 2 patients.

CONCLUSIONS

We report on a large cohort of patients with DDNLH, etiologically related to Helicobacter pylori infection.

Pathogenesis and treatment of gastrointestinal disease in antibody deficiency syndromes

Primary humoral immune deficiencies are characterized by limited antibody responses secondary to either impaired B-lymphocyte development or B-cell responses to T-lymphocyte signals. Given that the gastrointestinal tract is the largest lymphoid organ in the body, it is not surprising that intestinal diseases are common in immunodeficiency. These gastrointestinal diseases can be classified into one of 4 groups, infection, malignancy, inflammatory, and autoimmune, and can mimic other known disease processes, such as inflammatory bowel disease and celiac sprue. The exact pathogenesis of these gastrointestinal disorders in the setting of systemic immunodeficiency is still under investigation. However, studies suggest that defects in antibody deficiency alone do not result in gastrointestinal disease but rather that defects in cellular immunity are also involved. Treatment is difficult given an already immunocompromised state, and often therapy with immunomodulators is required for more severe processes.

[Gastrointestinal diseases in primary immunodeficiency disorders]

Gastrointestinal symptoms are common and often reveal primary immunodeficiency. Although they mimic gastrointestinal diseases observed in immunocompetent patients, there have diagnostic and therapeutic specificities that should be known for optimal management of these patients. This review describes the gastrointestinal diseases found in primary immunodeficiency and proposes some diagnostic and therapeutic strategies.

Gastrointestinal manifestations in patients with common variable immunodeficiency

This study focuses on endoscopic and pathologic alterations of gastrointestinal (GI) disorders of Iranian patients with common variable immunodeficiency (CVID). Nineteen of 39 CVID patients (48%) had GI complaints. The most common symptom was chronic diarrhea (28%). In endoscopic examination of small intestines, 15 patients had no abnormal finding. Duodenal biopsy revealed villous atrophy in eight and nodular lymphoid hyperplasia in three patients. There was no statistically significant difference between patients with and patients without duodenal villous atrophy regarding the presence of chronic diarrhea, anemia, and absolute CD4+T cells. In three patients, biopsies of the colon showed chronic noncrypt-destructive colitis. GI problems pose a high morbidity to CVID patients and are second only to respiratory complications. CVID patients are at increased risk of infectious and inflammatory conditions in the GI tract. Early diagnosis of these complications improves the quality of life and well-being of patients.

Clinical characteristics of a group of adults with nodular lymphoid hyperplasia: A single center experience

AIM: To describe the clinical and histological characteristics of a group of adults with small-bowel nodular lymphoid hyperplasia (NLH).

METHODS: Patients were searched for five years in pathology records of our institution. The biopsy material was reassessed using strict histopathological criteria. Clinical data were obtained from medical records.

RESULTS: Small-bowel NLH was diagnosed in 18 cases. The female: male ratio was 2∶1. The most frequent symptoms were diarrhea (72%), involuntary weight loss (72%) and abdominal pain (61%). Nine patients (50%) had immunodeficiency. Small-bowel bacterial overgrowth was found in three (17%) cases. At small-bowel NLH diagnosis, three (17%) had associated lymphoma: two intestinal and one extra-intestinal lymphomas. In two patients with villous atrophy and anti-endomysial antibodies the diagnosis of celiac disease was established. Giardia lamblia infection was found in only one patient with hypogammaglobulinemia (Herman’s syndrome).

CONCLUSIONS: NLH is uncommon in adult patients. Associated diseases are immunodeficiency and lymphoid tissue malignancies.

Familial adenomatous polyposis and duodenal lymphoma: report of a case

The occurrence of duodenal polyposis is well recognized in familial adenomatous polyposis. Lymphoid hyperplasia in association with familial adenomatous polyposis usually occurs in the terminal ileum, but it can occur in the duodenum and may be endoscopically difficult to distinguish from an adenoma. A case report is presented in which a 54-year-old male with familial adenomatous polyposis, who 20 years earlier had a subtotal colectomy and ileorectal anastomosis, presented with a large rectal villous tumor and was found to have a duodenal extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue. The role of lymphoid hyperplasia in the development of mucosa-associated lymphoid tissue lymphoma is discussed, as well as the issue of mucosa-associated lymphoid tissue lymphoma in familial adenomatous polyposis. In cases in which biopsies of polypoid lesions in patients with familial adenomatous polyposis show dense lymphoid aggregates, flow cytometry may assist in the diagnosis.

Review article: the non-inherited gastrointestinal polyposis syndromes

The non-inherited gastrointestinal polyposis syndromes represent a group of rare disorders characterized by the presence of multiple, non-adenomatous polyps on the gastrointestinal mucosa occurring in unrelated patients. We present here a review of the clinical and histo- pathological aspects of the syndromes to include the Cronkhite-Canada syndrome, hyperplastic polyposis and lipomatous polyposis. While infrequently encountered, these diseases can have devastating clinical effects that may be aggravated by delays in diagnosis and treatment. Prompt accurate diagnosis and treatment of these uncommon disorders depend on a sound working knowledge of the distinct clinical and pathological features described herein.

Terminal ileal imaging with ileoscopy versus small-bowel meal with pneumocolon

Disease of the terminal ileum can be diagnosed by ileocolonoscopy or barium radiography. We compared the diagnostic accuracy in the terminal ileum of ileocolonoscopy and small-bowel meal with pneumocolon. Consecutive patients during an 18-month period who had both ileocolonoscopy and small bowel meal with pneumocolon were identified and their colonoscopy reports, radiographs, and ileal biopsies reviewed blindly by paired gastroenterologists, radiologists, and pathologists, respectively. A gold-standard diagnosis was determined for each patient by consensus. Of 48 study subjects, 14 (29.2%) had Crohn's disease, 5 (10.4%) had lymphoid nodular hyperplasia, and 29 (60.4%) were normal. The sensitivity for a diagnosis of Crohn's ileitis was 92.9% for ileocolonoscopy and 100% for small-bowel meal, while their specificities were 100% and 97.1% respectively. The gold standard diagnosis confirmed ileocolonoscopic findings in 45 patients (93.8%) and radiographic findings in 42 patients (87.5%). Agreement between ileocolonoscopy and small bowel meal occurred in 39 cases (81.2%). By combining histology with ileocolonoscopy, the sensitivity and specificity could be increased to 100% for all diagnoses. Ileocolonoscopy and small-bowel meal with pneumocolon are complementary techniques for imaging the terminal ileum. A prospective comparative trial is now needed to more objectively assess their accuracy, cost effectiveness, and adverse effects.