Medication-associated lesions of the GI tract

Drug-induced mucosal alterations observed during esophagogastroduodenoscopy

Several features of drug-induced mucosal alterations have been observed in the upper gastrointestinal tract, i.e., the esophagus, stomach, and duodenum. These include pill-induced esophagitis, desquamative esophagitis, worsening of gastroesophageal reflux, chemotherapy-induced esophagitis, proton pump inhibitor-induced gastric mucosal changes, medication-induced gastric erosions and ulcers, pseudomelanosis of the stomach, olmesartan-related gastric mucosal inflammation, lanthanum deposition in the stomach, zinc acetate hydrate tablet-induced gastric ulcer, immune-related adverse event gastritis, olmesartan-asso-ciated sprue-like enteropathy, pseudomelanosis of the duodenum, and lanthanum deposition in the duodenum. For endoscopists, acquiring accurate knowledge regarding these diverse drug-induced mucosal alterations is crucial not only for the correct diagnosis of these lesions but also for differential diag-nosis of other conditions. This minireview aims to provide essential information on drug-induced mucosal alterations observed on esophagogastroduodenoscopy, along with representative endoscopic images.

Iron Pill-Induced Chemical Laryngitis

OBJECTIVE

To discuss the presentation and management of pill-induced chemical laryngitis by illustrating a rare case.

METHODS

We report a unique case of a patient with iron pill-induced laryngitis.

RESULTS

A 71-year-old male presented for evaluation of dysphonia. Five weeks prior, the patient had reportedly aspirated an iron pill. The pill was lodged in his throat for several hours before being coughed up, soft but still intact. Since that event, the patient noted complete voice loss and in clinic was found to have a very breathy and asthenic voice. Stroboscopy revealed aperiodicity with severe false fold compression and significant ulceration of the infraglottic region associated with thick exudate. Vocal folds were mobile but atrophic, with overlying crusted secretions. A sensory deficit was suspected based on scope tolerance. The patient was treated with nebulized ciprodex and humidified air with some improvement in mucosal crusting but had persistent glottic insufficiency and dysphonia, prompting bilateral hyaluronic acid injection.

CONCLUSIONS

Pill-induced laryngitis is an extremely rare phenomenon. While typically associated with bisphosphonates, this condition should be considered in any patient presenting with dysphonia and history of aspiration of a pill, including iron supplements. Regardless of the inciting medication, pill-induced laryngitis may be treated with humidified air, nebulized steroids, and antibiotics. Injection augmentation of the vocal folds may be made considered when glottic insufficiency and weak cough contribute to the presentation.

Drug-induced esophageal injuries with an atypical presentation mimicking acute coronary syndrome

Background

Pill-induced esophageal injury may cause severe complications if not diagnosed in a timely fashion. The condition is under-recognized and under-reported, and some patients present with atypical clinical or endoscopic features mimicking other common conditions. If the diagnosis is missed the patient will continue to take the offending drug, potentially worsening the illness. We present a case in which acute coronary syndrome was the initial working diagnosis leading to a delay in diagnosis of doxycycline-induced esophageal injury. The patient developed multiple esophageal ulcers and hemorrhage.

Case presentation

A 50-year-old male driver with a history of hypertension and dyslipidemia was brought to the emergency department with complaints of severe retrosternal chest pain, vomiting, diaphoresis and syncope. On initial evaluation, acute coronary syndrome was considered due to the clinical presentation and history of cardiovascular risk factors. Electrocardiogram and serum troponins were normal. On the second day of his admission, the patient developed odynophagia and bloody vomitus. Esophagogastroduodenoscopy revealed extensive esophageal ulcerations with hemorrhage. The patient was taking Doxycycline capsules for an acute febrile illness. Doxycycline is the oral medication most commonly reported to cause esophageal injury. Doxycycline was discontinued, and the patient was treated with intravenous omeprazole and oral antacid suspension. The patient improved, was discharged after 6 days of hospitalization, and reported resolution of all symptoms at an outpatient follow-up visit 3 weeks later.

Conclusion

Medication-induced esophageal injury can present with atypical symptoms mimicking acute coronary syndrome. This condition should be included in the initial differential diagnosis of patients presenting with acute chest pain, especially those taking oral medications known to cause esophageal injury.

Review article: drug-induced small bowel injury

BACKGROUND

Drug-induced gastrointestinal injury has been increasingly reported, but its exact incidence is not known. The small and large intestines represent the most affected sites of injury, accounting for 20%-40% of all gastrointestinal side effects.

AIM

To provide an updated literature review detailing medications linked to the development of small bowel injury.

METHODS

We conducted a literature search on PubMed from its inception to May 1, 2021. We included English-language original studies, meta-analyses, systematic reviews, review articles and case reports.

RESULTS

Drug-induced enteropathy can range from asymptomatic histological changes resulting in a subtle, self-limited disease to a chronic inflammatory condition mimicking inflammatory bowel disease, or bowel perforation. Endoscopy can demonstrate erythema, mucosal friability, oedema, erosions, ulcers or strictures in severe cases. Histology may include mucosal erosions and ulcerations, focal active enteritis, villous atrophy, epithelial apoptosis or necrotising enteritis. A well-established association has been found with the use of nonsteroidal anti-inflammatory drugs, immunosuppressants, chemotherapeutic agents, antibiotics, immunotherapies, etanercept and olmesartan. Possible associations have been reported with other biologic agents, medications used for glycemic control, antihypertensives, cholinesterase inhibitors, potassium and iron supplements, with conflicting data regarding contraceptives/hormonal therapy and isotretinoin.

CONCLUSION

Physicians should be aware of the manifestations of drug-induced enteropathy as early recognition can lead to prompt discontinuation of the offending therapy and, therefore, a reduced risk of future complications.

New Kids on the Block

CONTEXT.—

With the increasing development and use of iatrogenic agents, pathologists are encountering more novel foreign materials in retrieved gastrointestinal specimens. These colorful and unusual-appearing foreign materials can pose a diagnostic dilemma to those unaware of their morphology, especially if the relevant clinical history is lacking.

OBJECTIVE.—

To discuss the histopathologic features, clinical scenarios and significance, and differential diagnosis of relatively recently described, yet quickly expanding, family of iatrogenic agents that can present as foreign materials in gastrointestinal specimens-pharmaceutical fillers (crospovidone and microcrystalline cellulose), submucosal lifting agents (Eleview and ORISE), lanthanum carbonate, hydrophilic polymers, OsmoPrep, yttrium 90 microspheres (SIR-Sphere and TheraSphere), and resins (sodium polystyrene sulfonate, sevelamer, and bile acid sequestrants).

DATA SOURCES.—

We collate the findings of published literature, including recently published research papers, and authors' personal experiences from clinical sign-out and consult cases.

CONCLUSIONS.—

Correct identification of these iatrogenic agents is important because the presence of some novel agents can explain the histopathologic findings seen in the background specimen, and specific novel agents can serve as diagnostic clues to prompt the pathologist to consider other important and related diagnoses. Awareness of even biologically inert agents is important for accurate diagnosis and to avoid unnecessary and expensive diagnostic studies.

Lesions in the oral cavity and esophagus caused by prescribed drugs: A review

Almost all drugs, including some plant-based compounds, can have adverse effects, about 10% of which are expressed at the level of the digestive tract and in some cases resemble gastrointestinal diseases. Most commonly manifest as difficult and/or painful swallowing, nausea, vomiting, diarrhea and constipation. In rare cases, lesions caused by medications may be complicated by bleeding, strictures and perforations and can manifest in all segments of the gastrointestinal tract (GIT). The diagnosis is made from a detailed medical history and clinical examination inter alia. and best confirmed by proximal or distal endoscopy.

Alteration of the gut microbiome in mycophenolate-induced enteropathy: impacts on the profile of short-chain fatty acids in a mouse model

BACKGROUND

Mycophenolic acid (MPA) is the most widely used immunosuppressive drug in transplantation and for autoimmune diseases. Unfortunately, more than 30% of patients experience a typical gastrointestinal adverse effect also referred to as mycophenolate-induced enteropathy. Due to its antibacterial, antifungal, and antiviral properties, MPA exposure is associated with intestinal dysbiosis characterized by a decrease in density and diversity of the microbiome regarding the main bacterial phyla (Firmicutes and Bacteroidetes). These bacterial phyla are known for their metabolic role in maintaining the homeostasis of the digestive tract, particularly through the production of short-chain fatty acids (SCFA) that could contribute to the pathophysiology of mycophenolate-induced enteropathy. Our study aimed at deciphering short-chain fatty acids (SCFA) profile alterations associated with gastrointestinal toxicity of MPA at the digestive and systemic levels in a mouse model.

METHODS

Ten-week old C57BL/6 (SOPF) mice were randomly assigned in 2 groups of 9 subjects: control, and mycophenolate mofetil (MMF, 900 mg/kg/day). All mice were daily treated by oral gavage for 7 days. Individual faecal pellets were collected at days 0, 4 and 8 as well as plasma at day 8 for SCFA profiling. Additionally, after the sacrifice on day 8, the caecum was weighted, and colon length was measured. The proximal colon was cut for histological analysis.

RESULTS

MMF treatment induced around 10% weight loss at the end of the protocol associated with a significant decrease in caecum weight and a slight reduction in colon length. Histological analysis showed significant architectural changes in colon epithelium. Moreover, we observed an overall decrease in SCFA concentrations in faecal samples, especially regarding acetate (at day 8, control 1040.6 ± 278.161 μM versus MMF 384.7 ± 80.5 μM, p < 0.01) and propionate (at day 8, control 185.94 ± 51.96 μM versus MMF 44.07 ± 14.66 μM, p < 0.001), and in plasma samples for butyrate (at day 8, control 0.91 ± 0.1 μM versus MMF 0.46 ± 0.1 μM, p < 0.01).

CONCLUSIONS

These results are consistent with functional impairment of the gut microbiome linked with digestive or systemic defects during MMF treatment.

A prospective, randomized, placebo-controlled, double-blinded clinical trial comparing the incidence and severity of gastrointestinal adverse events in dogs with cancer treated with piroxicam alone or in combination with omeprazole or famotidine

OBJECTIVE

To assess the impact of prophylactic omeprazole and famotidine on the incidence and severity of gastrointestinal (GI) adverse events (AEs) in dogs with cancer treated with single agent piroxicam.

ANIMALS

39 dogs with a cytologic or histologic diagnosis of cancer with no history of GI disease and received piroxicam.

PROCEDURES

A prospective, randomized, placebo-controlled, double-blinded clinical trial was performed. All dogs received piroxicam (0.3 mg/kg [0.14 mg/lb], PO, q 24 h) and either omeprazole (1 mg/kg [0.45 mg/lb], PO, q 12 h), famotidine (1 mg/kg, PO, q 12 h), or placebo (lactose; PO, q 12 h). Monthly assessments of GI AEs were performed and scored by using the Veterinary Comparative Oncology Group's Common Terminology Criteria for Adverse Events (version 1.1).

RESULTS

Compared with dogs in the placebo group, more dogs in the omeprazole group (84.6% vs 36.4%) and famotidine group (80.0% vs 36.4%) experienced GI AEs by day 56. The severity of GI AEs was higher in the omeprazole group, compared with the placebo group.

CONCLUSIONS AND CLINICAL RELEVANCE

Omeprazole was not helpful in reducing the frequency or severity of GI AEs and was associated with more frequent and severer GI AEs in dogs with cancer treated with single agent piroxicam. Proton-pump inhibitors and H2-receptor antagonists should not be prescribed as prophylaxis with NSAIDs for dogs with cancer.

Keratinocyte growth factor ameliorates mycophenolate mofetil-induced intestinal barrier disruption in mice

OBJECTIVES

Although mycophenolate mofetil-induced (MMF) effectively improves long-term graft survival, the gastrointestinal (GI) side effects due to MMF-induced GI barrier damage limit its use in clinic. Keratinocyte growth factor (KGF) plays a crucial role in the intestinal protection and repair process. This study is designed to investigate the protective effect of KGF on MMF-induced intestinal mucosal barrier disruption and the potential mechanism.

METHODS

Thirty adult male C57BL/6 mice were assigned to one of the following groups: the MMF group, the MMF + KGF group, and the control group (n = 10 in each group). Animals in the MMF group received MMF (500 mg/kg) by gavage once daily for 15 consecutive days; animals in the MMF + KGF group received MMF (500 mg/kg) by gavage and KGF (5 mg/kg) by intraperitoneal injection once daily for 15 consecutive days; and control mice were given an equal volume of vehicle during the 15-day experimental period. In each group, intestinal paracellular permeability, histopathological changes and shifts in tight junction (TJ) protein were evaluated; further, proliferation and apoptosis of intestinal epithelial cells (IECs) were assessed, and intraepithelial lymphocytes (IELs) were isolated and analyzed by flow cytometry.

RESULTS

MMF caused intestinal mucosal injury, increased intestinal mucosal permeability, and altered expression of TJ protein. Moreover, MMF treatment inhibited IEC proliferation and increased apoptosis. MMF treatment resulted in a lower proportion of γδ⁺ T cells in IELs (γδ⁺ IELs). Conversely, concurrent administration of KGF with MMF effectively alleviated MMF-induced intestinal mucosal disruption, inhibited the increase in intestinal permeability, and maintained TJ protein expression. KGF also reversed the MMF-mediated inhibition of proliferation and promotion of apoptosis in IECs. In addition, KGF significantly enhanced the proportion of γδ⁺ IELs.

CONCLUSION

Our findings suggest that MMF induces intestinal epithelial barrier disruption in mice. KGF may play a protective role to ameliorate the disruption and provide a therapeutic intervention for gastrointestinal disorders induced by MMF.

Histopathologic Patterns of Colitis in Patients With Impaired Renal Function

OBJECTIVES

To characterize the histopathologic features of colitis in patients with impaired renal function.

METHODS

We retrospectively identified 413 patients who underwent colonoscopic evaluation for colitis between 2011 and 2015. Patients were divided into four groups based on estimated glomerular filtrate rates. Patients with impaired renal function were compared to overall and age-matched patients with normal renal function.

RESULTS

Compared to a preponderance of inflammatory bowel disease (33%) and lymphocytic colitis (9.6%) in patients with normal renal function, ischemic colitis (58%) was the predominant histopathologic pattern in the patients with impaired renal function. Infectious colitis was the second most common pattern (20.8%), with Clostridium difficile and cytomegalovirus infections being more frequent. Medication-induced injury was the third most common pattern, with crystal-associated injury being the exclusive pattern found in this study.

CONCLUSIONS

Colitis in patients with impaired renal function is etiologically distinct from that seen in patients with normal renal function.

Ilececum: A Comprehensive Review

For gastrointestinal endoscopists, the ileocecum is the finishing line during colonoscopy and it is identified by three endoscopic landmarks: terminal ileum, ileocecal valve, and the appendiceal orifice. Although ileal intubation is recommended during routine screening colonoscopy, it is not required in most cases of screening colonoscopy. Ileal intubation is indicated in certain circumstances such as suspected inflammatory bowel disease and GI bleeding. There is much pathology that can be observed within the ileocecum. Careful and systematic examination should be stressed during GI endoscopic training and practice. In this review, the authors demonstrate its anatomy, endoscopic findings, and pathologies.

Unique causes of esophageal inflammation: a histopathologic perspective

Gastroenterologists frequently perform endoscopic esophageal mucosal biopsies for pathologic diagnosis in patients experiencing symptoms of esophagitis. The more common causes of esophagitis diagnosed on esophageal mucosal biopsy include reflux esophagitis, eosinophilic esophagitis, and infectious esophagitis caused by Candida albicans, herpes simplex virus, and/or cytomegalovirus. However, there are several causes of esophagitis seen less frequently by pathologists that are very important to recognize. We discuss unique types of esophageal inflammation, including acute bacterial esophagitis, esophageal manifestations of dermatologic diseases, medication-induced esophageal injury, and sloughing esophagitis; and we review their clinical and histopathologic features.

Gastrointestinal complications induced by sevelamer crystals

Background

Sevelamer is a phosphate binder widely used in chronic kidney disease (CKD) patients. Sevelamer, as well as other resin-based binders, can crystallize leading to the formation of concretions. Sevelamer crystals (SC) have been associated with gastrointestinal (GI) mucosal injury. We describe three new cases of GI lesions associated with SC and review previously reported cases.

Methods

We describe three new cases of GI lesions associated with SC and review previously reported cases.

Results

We found 16 previously reported cases of SC-induced GI lesions. The mean patient age was 61 years (interquartile range 51.5–71.75), 62.5% were females and 10 patients were diabetic. In 13 cases, SC was found inside the GI mucosa. Six patients had history of major abdominal surgery. GI bleeding was the most common clinical symptom (n = 7), with three patients presenting with acute abdomen requiring surgical intervention. Although, SC-induced lesions were observed in all GI segments, intestine was involved in 81% of the cases. Endoscopic examination revealed mainly erosions and ulcerations (n = 7) and pseudoinflammatory polyps (n = 5). No association between sevelamer doses and the severity of GI lesions was found. However, diabetics patients seemed to develop GI lesions with smaller doses of sevelamer as compared with non-diabetic patients, in spite of their fewer GI comorbidities.

Conclusions

SC-induced GI lesions should be considered in CKD patients treated with sevelamer who present GI symptoms, especially lower GI bleeding, once other causes have been ruled out. Diabetics seem more prone to develop SC- associated GI lesions. Sevelamer therapy should be avoided if possible in patients with a history of major abdominal surgery or chronic constipation, because of the high risk of serious GI complications.

Role of endoplasmic reticulum stress in drug-induced toxicity

Drug‐induced toxicity is a key issue for public health because some side effects can be severe and life‐threatening. These adverse effects can also be a major concern for the pharmaceutical companies since significant toxicity can lead to the interruption of clinical trials, or the withdrawal of the incriminated drugs from the market. Recent studies suggested that endoplasmic reticulum (ER) stress could be an important event involved in drug liability, in addition to other key mechanisms such as mitochondrial dysfunction and oxidative stress. Indeed, drug‐induced ER stress could lead to several deleterious effects within cells and tissues including accumulation of lipids, cell death, cytolysis, and inflammation. After recalling important information regarding drug‐induced adverse reactions and ER stress in diverse pathophysiological situations, this review summarizes the main data pertaining to drug‐induced ER stress and its potential involvement in different adverse effects. Drugs presented in this review are for instance acetaminophen (APAP), arsenic trioxide and other anticancer drugs, diclofenac, and different antiretroviral compounds. We also included data on tunicamycin (an antibiotic not used in human medicine because of its toxicity) and thapsigargin (a toxic compound of the Mediterranean plant Thapsia garganica) since both molecules are commonly used as prototypical toxins to induce ER stress in cellular and animal models.

Histomorphological and Immunophenotypic Features of Pill-Induced Esophagitis

The aim of this study was to investigate histomorphological and immunophenotypic features in pill-induced esophagitis. We comparatively evaluated the histomorphological, immunophenotypic features of pill-induced esophagitis vs. reflux esophagitis, as well as clinical information and endoscopic findings. Fifty-two tissue pieces from 22 cases of pill-induced esophagitis, 46 pieces from 20 reflux esophagitis, and 16 pieces from 14 control samples were subjected to immunohistochemistry for inflammatory infiltrates (CD3 for T lymphocyte, CD20 for B lymphocyte, CD56 for NK cell, CD68 for macrophage, CD117 for mast cell) and eosinophil chemotaxis-associated proteins (Erk, leptin, leptin receptor, pSTAT3, phospho-mTOR). As a result, Histomorphology showed that a diffuse pattern of dilated intercellular spaces was more frequently observed in pill-induced esophagitis, while reactive atypia and subepithelial papillary elongation were more often found in reflux esophagitis (P < 0.05, respectively). Interestingly, intraepithelial eosinophilic microabscess, intraepithelial pustule and diffuse pattern of dilated intercellular spaces were observed in 14% (3 cases), 9% (2 cases) and 32% (7 cases) of pill-induced esophagitis, respectively, but in no cases of reflux esophagitis. Regarding intraepithelial inflammatory infiltrates in pill-induced esophagitis, T lymphocytes were the most common cells, followed by eosinophil; 11 and 7 in one x400 power field, respectively. Intraepithelial pSTAT3-positive pattern was more frequently observed in pill-induced esophagitis than in reflux esophagitis, at 45% (10 cases) versus 10% (2 cases), respectively (P < 0.05). Considering the distal esophageal lesion only, intraepithelial pustule, diffuse dilated intercellular spaces and stromal macrophages were more frequently found in distal pill-induced esophagitis, whereas reactive atypia and intraepithelial mast cells in reflux esophagitis (P < 0.05, respectively). In conclusion, diffuse dilated intercellular spaces, intraepithelial eosinophil microabscess, pustule, T lymphocytes, eosinophils, and pSTAT3 positivity can be added to histopathological features of pill-induced esophagitis, other than non-specific ulcer. Besides, distal pill-induced esophagitis may be histopathologically differentiated from reflux esophagitis.