Introduction

Materials and methods

This is a descriptive cross-sectional study of patients who were diagnosed using VCE between January 2014 and December 2017. A detailed review of variables in the data obtained through the procedure and in the hospital’s medical history and the medical histories provided by outpatients. The data was recorded in Excel for further statistical analysis.

Table 1 contains demographic data including the numbers of inpatients and outpatients, indications for VCE, and the primary reason the patient was referred to our hospital as well as risk factors such as cigarette smoking, alcohol consumption, use of non-steroid anti-inflammatory drugs (NSAIDs), glucosamine, homeopathic medicines, anticoagulants, antiplatelet drugs, liver disease and history of chronic kidney disease (CKD). The preparation prior to VCE and findings from VCE are described in the results section.

Table 1 Demographic and clinical data plus indications for VCE at HPTU 

IBD: inflammatory bowel disease; VCE: endoscopic videocapsule.

Patients over the age of 15 years were included after signing the hospital’s informed consent form.

Results

A total of 374 VCE studies were performed in the study period: 282 were outpatients (169 women, 113 men) and 92 patients (49 women, 43 men) were inpatients. Average participant age was 56.5 with a range of 15 to 92 years.

Preparation of the small bowel was considered to be adequate in 79/92 (85.87%) of the inpatients and in 258/282 (91.49%) of the outpatients. The most frequent indication was occult digestive bleeding for both outpatients and inpatients. It was observed in 109/282 (38.65%) of the outpatients and in 50/92 (53.26%) of the inpatients. Second most frequent among outpatients was chronic anemia in 78/282 (27.65%) while second most frequent among inpatients was follow-up or diagnosis of with Crohn’s disease in 20/92 (21.74%).

Risk factors related to digestive bleeding identified in inpatients included smoking (17/92, 18.48%), antiplatelet drugs (15/92, 16.30%), NSAIDs (7/92, 7.60%) and alcohol consumption (3/92, 3.26%). An ulcer with severe inflammatory stenosis was identified in one patient who had taken glucosamine (Figure 1A). Risk factors related to digestive bleeding identified in outpatients included smoking (40/282, 14%), alcohol consumption (26/282, 9%), use of antiplatelet drugs or anticoagulants (28/282, 10%), NSAIDs (25/282, 8.8 %), glucosamine (4/282, 1.4%), homeopathic drugs (1/282), chronic liver disease (9/282, 3.1%) and CKD (13/282, 4.6%).

In order of frequency, outpatients’ symptoms were anemia in 134 patients (47.52%), chronic diarrhea in 54 patients (19.15%), manifest digestive bleeding in 45 patients (15.95%), unexplained weight loss in 23 patients (8.15%) and abdominal pain in 16 patients (5.67%). For inpatients, the most frequent symptoms were bleeding in 49 patients (53.26%), anemia in 22 patients (23.91%), diarrhea in 15 patients (16.30%), abdominal pain in 4 patients (4.35%) and recurrent oral aphthae in one patient (1.08%).

Endoscopy had been performed previously on 86/92 inpatients (93.5%) and 81/92 (88%) had undergone colonoscopy.

Eighteen of the inpatients (19.56%) underwent enteroscopy due to abnormal VCE findings. Of these, ten had vascular lesions due to angiodysplasias and underwent enteroscopy with argon plasma coagulation. Five of these had been diagnosed with Osler-Weber-Rendu syndrome. Inflammation, tumors, or other lesions were found in the other eight patients, so they underwent enteroscopy to take biopsies and mark the lesions.

Of the 159 cases of occult digestive bleeding in both groups, 73 cases (45.91%) were due to vascular causes and 53 cases (33.33%) were due to inflammatory lesions. Potential sources of bleeding were identified in more than 70% of the 93 total cases of anemia: vascular lesions in 36 cases (38.71%) followed by inflammation in 26 cases (27.95%) and tumors in six cases (6.45%). Of the 62 cases related to diagnosis and follow-up of inflammatory bowel disease, 34 cases (54.83%) had inflammatory lesions (Figures 1B-1D) and seven cases (11.29%) had vascular lesions.

Figure 1A Ulcerated enteritis with stenosis due to glucosamine consumption. 1B. Ulcerated ileitis in a patient with Crohn’s disease. 1C. Inflammatory hemi-circumferential ulcer in the ileum of a patient with Crohn’s disease. 1D. Inflammatory ulcers with active bleeding in the jejunum. 

 The most frequent location of abnormal findings in inpatients was the jejunum (43/92, 46.7%), and in these patients the most frequent lesions were angiodysplasias (32/43, 74.4%) and inflammatory lesions (18/43, 41.8%). The duodenum was the second most common location (39/92, 42.3%), but in these patients the most frequent lesions were angiodysplasias (27/39, 69.2%) followed by inflammatory lesions (17/39, 43.5%) (Table 2).

Table 2 Location and type of lesions diagnosed by VCE at HPTU 

Twelve tumors were documented. Six were benign polyps in the stomach and duodenum, one patient had a gastric neoplasia and the rest had ulcerated subepithelial lesions that were related to neuroendocrine tumors in the jejunum and ileum.

Discussion

Currently available techniques for evaluation of the small bowel include VCE, balloon enteroscopy, CT enterography, magnetic resonance enterography and intraoperative enteroscopy (which is rare). These modalities can recognize the majority of small bowel lesions and can impact therapeutic strategies by making surgical interventions unnecessary or by decreasing surgical times due to better localization of a lesion. ^1,2,3,6 Despite these advances in the study of the small bowel, the most efficient approach for management of patients suspected of bleeding in the small bowel bleeding has not been fully determined. Nevertheless, the strongest recommendation is to use VCE for diagnosis. ^1,2,6 Because of all this growth in diagnostic methods to explore the small bowel, a recently published clinical guide recommends changing the term occult digestive bleeding to small bowel bleeding, reserving the term occult digestive bleeding for bleeding that cannot be identified after evaluation of the entire gastrointestinal tract. ⁷

The work of Maeda et al. has shown that the sensitivity and negative predictive value of VCE are both 100% for presence of lesions in the small bowel and for the therapeutic approach in cases with significant lesions. In this study, the VCE never missed the relevant findings in the small bowel. A fact of great interest is that the negative findings of a VCE almost always corresponded to an inadequate indication.³ A recent systematic review and metaanalysis has shown that negative VCE indicates a low risk of rebleeding in the future. Therefore, these patients should be discharged and can be treated safely with watchful waiting. ⁸ Nevertheless, a letter to the editor about that systematic review and metaanalysis has warned that negative results of an examination should never reassure an attending physician. On the contrary, close monitoring and a low threshold for repeating endoscopy is recommended in order to identify lesions not related to the small bowel in patients with overt bleeding. ⁹ Patients who bleed again after two years may need additional diagnostic study. ⁸

Diagnostic yield evidenced in the data used in this study was good: potential causes were documented for more than 70% of the two most frequent indications, digestive bleeding and anemia. A recent metaanalysis has found that the combined diagnostic yield of VCE in patients with occult digestive bleeding (overt or hidden) was 61.7%. ¹⁰ Several factors influence the probability of finding the lesion which causes the bleeding: active bleeding, a decrease of more than 3 g of hemoglobin, and the time of the study with respect to the last day of bleeding. Depending on these factors, the yield can vary between 11% and 87%.^1,6

Inflammatory lesions were identified in 50% of the patients in our study who were suspected of having of inflammatory bowel disease or who had previous been diagnosed with IBD. Although up to 66% of patients with Crohn’s disease have small bowel compromise at diagnosis, up to 90% are in the distal ileum. ¹¹ Some studies have shown that VCE evaluation of the small bowel increases diagnoses of Crohn’s disease by 22% to 24% due to discovery of lesions not evidenced in imaging studies and not found through colonoscopy due to the impossibility of entering the ileum.^12,13 This makes the VCE an ideal complementary method for patients who have symptoms compatible with Crohn’s disease as well as for patients with elevated acute phase reactants or fecal calprotectin for whom an accurate diagnosis of the disease and/or its extension has been impossible to reach. VCE can result in reclassifying patients who had initially been diagnosed with ulcerative colitis or indeterminate colitis. When evidence of lesions in the small bowel is found, they should be managed as if they had Crohn’s disease. In addition, learning the degree of small bowel compromise can have implications for treatment, monitoring and prognosis of the disease. Finally, VCE can be used to monitor known lesions to evaluate response to treatment and determine deep remission or the need for modifications in maintenance therapy. ¹⁴

The capsule was fundamental for making diagnostic and therapeutic decisions in relation to abnormal findings. Double-balloon enteroscopy was performed in almost 20% of the inpatients with obscure gastrointestinal bleeding. Some of these were for therapeutic purposes through application of argon plasma coagulation of vascular lesions while others were diagnostic through taking of biopsies and marking of tumors for resection. For all cases of enteroscopy, VCE findings guided definition of the enteroscope entry path (antegrade or retrograde) by the topographic location in accordance with recommendations in the literature.^1,2,3,6,7

Most inpatients had previously undergone endoscopy (86/92, 93.5%) and (81/92, 88%). But many patients in the study were outpatients, including those referred from other cities, who had not. Also, diagnostic suspicion of CD compromising the small bowel was the second most common reason for examining inpatients. For these patients, VCE is used to establish the extent of the disease and compromise of the small bowel. ¹⁰ Consequently, these data differ from those reported by Dr. Galiano et al. One hundred percent of that cohort of patients had had upper gastrointestinal endoscopy and colonoscopy before the VCE study. ⁴ Despite this, we do agree with, and adhere to, recommendations for conducting baseline studies, especially for patients with occult digestive bleeding or chronic anemia with suspected gastrointestinal blood loss.

The risks inherent to VCE are low. Retention of the capsule has been described, but this occurs in only about 1% of cases. ⁴ In our series there were no complications. Patients with obstructive symptoms such as vomiting associated with distension and/or abdominal pain have the greatest risks of capsule retention, so it is recommended that their small bowels be studied with CT enterography or MR enterography depending on local experience and institutional availability. ⁶

In conclusion, of the multiple indications for VCE in our center, occult digestive bleeding and anemia were the most frequent, and the diagnostic yield exceeded 70%. For inpatients, VCE was used to study and evaluate those with suspected or known diagnoses of Crohn’s disease. In the latter case, VCE provides exceptional additional information related to diagnosis, classification, prognosis and follow-up.

VCEs are safe - there were no complications related to this procedure in this study - and it is a very useful tool for defining the route of entry and the initial approach to digestive bleeding. To date, this is the largest series published in Colombia. Multicenter studies are recommended for our country so that we can gain a better understanding of the prevalence and incidence of small bowel lesions while learning the operational characteristics of this method in our population.