An Approach to the Patient With Chronic Undiagnosed Abdominal Pain

Gastrointestinal disorders - Clinical challenges for the primary care clinician

Gastrointestinal (GI) associated symptoms are among the most common medical concerns resulting in visits to primary and specialty care. Especially challenging is the wide range of causative disorders and exposures associated with symptoms ranging from mild to life threatening - from within the GI tract as well as extra-gastrointestinal. Some of these are well described, and common, including infections, while others are newly emerging, such as cannabinoid hyperemesis syndrome. Others are well known but clinical success can remain elusive, such as food associated GI disorders - lactose intolerance and related. Although entire references have been written to address gastrointestinal diseases, in this edition of Disease a Month we will address some of the more challenging GI disorders; some of which are common but often difficult to control - food associated for example, and emerging GI illnesses such as radiation or cannabinoid hyperemesis, that lead patients to the Emergency Department, primary care clinician or specialty referral. What follows is a discussion of diverse but clinically important GI disorders, and the newer therapeutic strategies to help patients better manage their symptoms, and improve their quality of life.

Parietal abdominal pain with lower leg discrepancy: a case report

BACKGROUND

This report involves the first publication describing a case of parietal abdominal pain due to lower limb length discrepancy.

CASE PRESENTATION

A Caucasian male patient in his 50s was referred to our rehabilitation department with chronic abdominal pain that began in childhood. This chronic pain was associated with episodes of acute pain that were partially relieved by grade 3 analgesics. The patient was unable to sit for long periods, had recently lost his job, and was unable to participate in recreational activities with his children. Investigations revealed contracture and hypertrophy of the external oblique muscle and an limb length discrepancy of 3.8 cm (1.5 inches) in the left lower limb. The patient was effectively treated with a heel raise, physiotherapy, intramuscular injection of botulinum toxin, and lidocaine. The patient achieved the therapeutic goals of returning to work, and reducing analgesic use.

CONCLUSIONS

Structural misbalances, as may be caused by lower leg discrepancy, may trigger muscular compensations and pain. Complete anamnesis and clinical examination must not be trivialized and may reveal previously ignored information leading to a proper diagnosis.

Rare, Overlooked, or Underappreciated Causes of Recurrent Abdominal Pain: A Primer for Gastroenterologists

Recurrent abdominal pain is a common reason for repeated visits to outpatient clinics and emergency departments, reflecting a substantial unmet need for timely and accurate diagnosis. A lack of awareness of some of the rarer causes of recurrent abdominal pain may impede diagnosis and delay effective management. This article identifies some of the key rare but diagnosable causes that are frequently missed by gastroenterologists and provides expert recommendations to support recognition, diagnosis, and management with the ultimate aim of improving patient outcomes.

Gastroenterologist Primer: Endometriosis for Gastroenterologists

BACKGROUND AND AIM

A comprehensive understanding of endometriosis and its common gastrointestinal presentations are critical for gastroenterologists to ensure appropriate and timely screening and diagnosis. Endometriosis is a common inflammatory disease that frequently presents with gastrointestinal symptoms overlapping with irritable bowel syndrome (IBS) and other gastrointestinal disorders. Many endometriosis patients first present to a gastroenterologist or generalist, which may prolong the time to diagnosis and appropriate care.

METHOD AND RESULTS

This review describes the current literature on endometriosis presentation, overlap with gastrointestinal conditions, and standard diagnostic and treatment options for gastroenterologists to consider. For appropriate and swift treatment, gastroenterologists must consider an endometriosis diagnosis in females of menstruating age presenting with pain, bloating, altered stools, and non-gastrointestinal symptoms and refer patients for further evaluation.

Consider Hereditary Angioedema in the Differential Diagnosis for Unexplained Recurring Abdominal Pain

Health care providers are likely to encounter patients with recurrent unexplained abdominal pain. Because hereditary angioedema (HAE) is a rare disease, it may not be part of the differential diagnosis, especially for patients who do not have concurrent skin swelling in addition to abdominal symptoms. Abdominal pain is very common in patients with HAE, occurring in up to 93% of patients, with recurrent abdominal pain reported in up to 80% of patients. In 49% of HAE attacks with abdominal symptoms, isolated abdominal pain was the only symptom. Other abdominal symptoms that commonly present in patients with HAE include distension, cramping, nausea, vomiting, and diarrhea. The average time from onset of symptoms to diagnosis is 6 to 23 years. Under-recognition of HAE in patients presenting with predominant gastrointestinal symptoms is a key factor contributing to the delay in diagnosis, increasing the likelihood of unnecessary or exploratory surgeries or procedures and the potential risk of related complications. HAE should be considered in the differential diagnosis for patients with unexplained abdominal pain, nausea, vomiting, and/or diarrhea who have complete resolution of symptoms between episodes. As highly effective targeted therapies for HAE exist, recognition and diagnosis of HAE in patients presenting with isolated abdominal pain may significantly improve morbidity and mortality for these individuals.

Baseline Predictors of Discontinuation of Prescription Drug Therapy for IBS-C: Cohort Analysis at an Integrated Healthcare System

BACKGROUND

Effective prescription drug treatment of constipation-predominant irritable bowel syndrome (IBS-C) requires patients to remain on daily therapy, yet predictive factors to optimize treatment selection are unknown.

AIMS

We assessed whether common comorbidities including chronic overlapping pain conditions (COPCs), mood disorders, or concurrent medications influence the risk of discontinuing IBS-C prescription drug therapy.

METHODS

We included all IBS-C patients who initiated treatment with the secretagogues linaclotide or lubiprostone across the Michigan Medicine healthcare system between 2012 and 2016. A Cox proportional hazards model was constructed to model time-to-treatment discontinuation as a valid, quantifiable measure of IBS medication persistence using hazards ratios (HR) with 95% confidence intervals (CI).

RESULTS

Our cohort included 225 patients on linaclotide and 492 on lubiprostone (mean age 48.3 years, 86.9% women, 46.6% with at least one COPC, 60.3% with at least one mood disorder) with an average follow-up of 2.1 years. Patients with at least one COPC (HR = 0.566; 95%CI = 0.371-0.863) and also women (HR = 0.535; 95%CI = 0.307-0.934) had a lower risk of discontinuing linaclotide, while COPCs predicted a trend toward increased discontinuation of lubiprostone (HR = 1.254; 95%CI = 0.997-1.576). Age, comorbid mood disorders, and baseline use of narcotics or benzodiazepines did not significantly mediate the risk of treatment discontinuation; our findings remained stable in univariate and multivariable analyses.

CONCLUSIONS

COPCs and sex appear to influence the likelihood of discontinuation of two commonly prescribed secretagogues, while mood disorders, narcotics, and benzodiazepines may not. Routine assessment for comorbid COPCs prior to initiating therapy may optimize IBS-C treatment selection and outcomes in practice.

Diagnostic Effect of Consultation Referral from Gastroenterologists to Generalists in Patients with Undiagnosed Chronic Abdominal Pain: A Retrospective Study

This study aimed to investigate consultation outcomes from gastroenterologists to generalist physicians for the diagnostic workup of undiagnosed chronic abdominal pain. This was a single-center, retrospective, descriptive study. Patients were included who were ≥15 years old and consulted from the Department of Gastroenterology to the Department of Diagnostic Medicine, to establish a diagnosis for chronic abdominal pain, at the Dokkyo University Hospital from 1 April 2016 to 31 August 2020. We retrospectively reviewed the patients' medical charts and extracted data. A total of 12 cases were included. Eight patients (66.7%) were diagnosed with and treated for functional gastrointestinal disorders (FGID) at the Department of Gastroenterology; their lack of improvement under treatment for FGID was the reason for their referral to the Department of Diagnostic Medicine for further examination. After this consultation, new possible diagnoses were generated for eight patients (66.7%). Six of the eight patients (75.0%) were diagnosed with abdominal wall pain (anterior cutaneous nerve entrapment syndrome, n = 3; myofascial pain, n = 1; falciform pain, n = 1; and herpes zoster non-herpeticus; n = 1). Consultation referral from gastroenterologists to generalists could generate new possible diagnoses in approximately 70% of patients with undiagnosed chronic abdominal pain.

Classification algorithm for the International Classification of Diseases-11 chronic pain classification: development and results from a preliminary pilot evaluation

ABSTRACT

The International Classification of Diseases-11 (ICD-11) chronic pain classification includes about 100 chronic pain diagnoses on different diagnostic levels. Each of these diagnoses requires specific operationalized diagnostic criteria to be present. The classification comprises more than 200 diagnostic criteria. The aim of the Classification Algorithm for Chronic Pain in ICD-11 (CAL-CP) is to facilitate the use of the classification by guiding users through these diagnostic criteria. The diagnostic criteria were ordered hierarchically and visualized in accordance with the standards defined by the Society for Medical Decision Making Committee on Standardization of Clinical Algorithms. The resulting linear decision tree underwent several rounds of iterative checks and feedback by its developers, as well as other pain experts. A preliminary pilot evaluation was conducted in the context of an ecological implementation field study of the classification itself. The resulting algorithm consists of a linear decision tree, an introduction form, and an appendix. The initial decision trunk can be used as a standalone algorithm in primary care. Each diagnostic criterion is represented in a decision box. The user needs to decide for each criterion whether it is present or not, and then follow the respective yes or no arrows to arrive at the corresponding ICD-11 diagnosis. The results of the pilot evaluation showed good clinical utility of the algorithm. The CAL-CP can contribute to reliable diagnoses by structuring a way through the classification and by increasing adherence to the criteria. Future studies need to evaluate its utility further and analyze its impact on the accuracy of the assigned diagnoses.

Chronic Abdominal Pain: Gastroenterologist Approach

BACKGROUND

Abdominal pain is a common symptom of gastroenterology examination. Chronic abdominal pain is present for >3 months.

SUMMARY

Gastroesophageal reflux disease (GERD) is one of the most common gastrointestinal diseases encountered by both gastroenterologists and general practitioners. GERD is usually a chronic disease presented with a set of symptoms including heartburn and/or regurgitation, and less commonly epigastric pain. Epigastric pain syndrome is characterized by the following symptoms: epigastric pain and/or burning. It does not necessarily occur after meal ingestion, may occur during fasting, and can be even improved by meal ingestion. Duodenal ulcers tend to cause abdominal pain that is localized in the epigastric region and commence several hours after eating, often at night. Hunger provokes pain in most of the cases and decreases after meal. Gastric ulcer pain occurs immediately after eating, and consuming food increases pain. Pain is localized in the epigastrium and can radiate to the back. Abdominal pain in irritable bowel syndrome is related to defecation. A typical symptom of chronic pancreatitis is pain that radiates to the back. In Crohn's disease, inflammation causes pain. Key Messages: Pain can occur at different locations with diverse intensity and propagation and is often associated with other symptoms. For any gastroenterologist, abdominal pain is a big challenge.

Chronic Abdominal Pain in General Practice

Background and Summary: Chronic abdominal pain is a challenging complaint for both primary care providers and gastroenterologists alike, due to a broad differential diagnosis and sometimes extensive and negative workup. In the absence of red flag features that herald more acute conditions, the majority of patients with chronic abdominal pain have a benign cause or a functional disorder (e.g., irritable bowel syndrome). The costs associated with a diagnostic workup are an expensive burden to health care. A systematic approach for evaluating patients and initiating a management plan are recommended in the primary care setting. Undiagnosed abdominal pain should be investigated starting with a detailed history and physical examination. Diagnostic investigations should be limited and adapted according to the clinical features, the alarm symptoms, and the symptom severity. This review will focus on the diagnostic tools which general practitioners utilize in the evaluation of chronic abdominal pain. Key Messages: The primary role of the general practitioner is to differentiate an organic disease from a functional one, to refer to a specialist, or to provide treatment for the underlying cause of pain. The functional disorders should be considered after the organic pathology has been confidently excluded. Once a diagnosis of functional pain is established, repetitive testing is not recommended and the patient should be referred to receive psychological support (e.g., cognitive therapy) associated with available pharmacological therapeutic options.

Identification of potential biomarkers for abdominal pain in IBS patients by bioinformatics approach

Background

Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disease characterized by chronic abdominal discomfort and pain. The mechanisms of abdominal pain, as a relevant symptom, in IBS are still unclear. We aimed to explore the key genes and neurobiological changes specially involved in abdominal pain in IBS.

Methods

Gene expression data (GSE36701) was downloaded from Gene Expression Omnibus database. Fifty-three rectal mucosa samples from 27 irritable bowel syndrome with diarrhea (IBS-D) patients and 40 samples from 21 healthy volunteers as controls were included. Differentially expressed genes (DEGs) between two groups were identified using the GEO2R online tool. Functional enrichment analysis of DEGs was performed on the DAVID database. Then a protein–protein interaction network was constructed and visualized using STRING database and Cytoscape.

Results

The microarray analysis demonstrated a subset of genes (CCKBR, CCL13, ACPP, BDKRB2, GRPR, SLC1A2, NPFF, P2RX4, TRPA1, CCKBR, TLX2, MRGPRX3, PAX2, CXCR1) specially involved in pain transmission. Among these genes, we identified GRPR, NPFF and TRPA1 genes as potential biomarkers for irritating abdominal pain of IBS patients.

Conclusions

Overexpression of certain pain-related genes (GRPR, NPFF and TRPA1) may contribute to chronic visceral hypersensitivity, therefore be partly responsible for recurrent abdominal pain or discomfort in IBS patients. Several synapses modification and biological process of psychological distress may be risk factors of IBS.

Understanding the most commonly billed diagnoses in primary care: Abdominal pain

ABSTRACT

Abdominal pain affects nearly every person at some point in their lifetime. Abdominal pain may be vague or referred, often making the diagnosis elusive and challenging for NPs. This article reviews the pathophysiology of abdominal pain in relation to clinical manifestations, differential diagnoses, and treatment.

Are Classic Bedside Exam Findings Required to Initiate Enteral Nutrition in Critically Ill Patients: Emphasis on Bowel Sounds and Abdominal Distension

The general physical examination of a patient is an axiom of critical care medicine, but evidence to support this practice remains sparse. Given the lack of evidence for a comprehensive physical examination of the entire patient on admission to the intensive care unit, which most clinicians consider an essential part of care, should clinicians continue the practice of a specialized gastrointestinal system physical examination when commencing enteral nutrition in critically ill patients? In this review of literature related to gastrointestinal system examination in critically ill patients, the focus is on gastrointestinal sounds and abdominal distension. There is a summary of what these physical features represent, an evaluation of the evidence regarding use of these physical features in patients after abdominal surgery, exploration of the rationale for and against using the physical findings in routine practice, and detail regarding what is known about each feature in critically ill patients. Based on the available evidence, it is recommended that an isolated symptom, sign, or bedside test does not provide meaningful information. However, it is submitted that a comprehensive physical assessment of the gastrointestinal system still has a role when initiating or administering enteral nutrition: specifically, when multiple features are present, clinicians should consider further investigation or intervention.

Treating Chronic Abdominal Pain in Patients with Chronic Abdominal Pain and/or Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is probably the most common diagnosis in gastroenterology involving the brain-gut axis. By definition, pain is the most frequent symptom experienced by patients. It is important to understand the biopsychosocial and physiologic aspects of the disease when discussing treatment of IBS. Such therapies as lifestyle modifications, changes in diet, and cognitive behavioral therapy should be used in conjunction with pharmacotherapy rather than pharmacotherapy alone. The pathophysiologic mechanisms are reviewed in this article along with the current treatments available, in the era of growing demand for more effective treatments for the pain component of IBS.

Updates in diagnosis and management of chronic abdominal pain

Chronic abdominal pain is a common problem seen by pediatricians and pediatric gastroenterologist alike. There should not be evidence of underlying organic pathology, with diagnosis based upon the Rome IV criteria. Although it frequently occurs, routine diagnostic testing is not always necessary. Providing assurance and helpful coping strategies is key in the management of chronic abdominal pain. Sometimes other expertise is needed when developing these strategies.