Overview
Definition:
Eosinophilic colitis (EC) is a chronic inflammatory disorder of the colon characterized by the infiltration of eosinophils into the colonic mucosa
Eosinophilic esophagitis (EoE) is a chronic immune-mediated esophageal disease characterized by eosinophilic inflammation in the esophagus, often triggered by food allergens.
Epidemiology:
EC is less common than EoE, with incidence estimates varying
It predominantly affects infants and young children, often presenting within the first year of life
EoE is more prevalent, particularly in children and young adults with a history of atopy, asthma, or allergic rhinitis
The prevalence of EoE has been increasing significantly.
Clinical Significance:
Both EC and EoE are important diagnoses in pediatric gastroenterology, often presenting with significant gastrointestinal symptoms that can impact growth and quality of life
Differentiating them is crucial for appropriate management, as therapeutic approaches differ
Understanding the overlap and distinct features aids in accurate diagnosis and optimal patient care, vital for DNB and NEET SS examinations.
Clinical Presentation
Symptoms:
Eosinophilic Colitis: Abdominal pain
Diarrhea, often bloody
Vomiting
Failure to thrive or weight loss
Rectal bleeding
Constipation (less common)
Eosinophilic Esophagitis: Dysphagia (difficulty swallowing)
Food impaction
Chest pain or abdominal pain mimicking GERD
Vomiting
Poor feeding or failure to thrive in infants.
Signs:
Eosinophilic Colitis: Abdominal tenderness
Pallor (due to anemia from bleeding)
Dehydration
Growth deceleration
Eosinophilic Esophagitis: Esophageal strictures or rings on endoscopy (may not be present initially)
Poor weight gain
Signs of atopy (eczema, wheezing).
Diagnostic Criteria:
Eosinophilic Colitis: Clinical symptoms suggestive of colitis
Endoscopic evidence of eosinophilic infiltration of the colonic mucosa (e.g., >15 eosinophils per high-power field)
Exclusion of other causes of colonic eosinophilia
Eosinophilic Esophagitis: Symptoms related to esophageal dysfunction
Endoscopic findings of esophageal eosinophilic inflammation (e.g., >15 eosinophils per high-power field in esophageal biopsies)
Absence of other causes of esophageal eosinophilia (e.g., GERD, parasitic infections).
Diagnostic Approach
History Taking:
Detailed history of feeding patterns, introduction of solid foods, and potential allergens
Family history of atopy, asthma, or allergies
Symptoms of gastroesophageal reflux disease (GERD) or dysphagia
Characterize stool consistency and frequency, presence of blood or mucus
Assess growth trajectory and weight gain
Elicit any history of food impaction.
Physical Examination:
Assess nutritional status and growth parameters (height, weight, head circumference)
Perform a thorough abdominal examination for tenderness, masses, or organomegaly
Evaluate for signs of dehydration
Auscultate lungs for wheezing
Examine skin for eczema or other signs of atopy.
Investigations:
Eosinophilic Colitis: Complete blood count (CBC) to assess for anemia and eosinophilia (peripheral eosinophilia may be absent)
Stool studies to rule out infectious causes
Colonoscopy with biopsies of the colon (multiple biopsies from different segments, including rectum and colon)
Biopsy should demonstrate significant eosinophilic infiltration (>15 eosinophils/HPF)
Eosinophilic Esophagitis: Upper endoscopy with esophageal biopsies (multiple biopsies from different levels of the esophagus)
Histopathological examination of biopsies for eosinophilic infiltration (>15 eosinophils/HPF)
Allergy testing (skin prick tests, specific IgE blood tests) can identify triggers
Esophageal manometry may be considered in older children with dysphagia.
Differential Diagnosis:
Eosinophilic Colitis: Allergic proctocolitis, infectious colitis, inflammatory bowel disease (IBD) in older children, inflammatory conditions with secondary eosinophilia (e.g., parasitic infections)
Eosinophilic Esophagitis: Gastroesophageal reflux disease (GERD), achalasia, infectious esophagitis, eosinophilic gastroenteritis involving the esophagus, food allergies without EoE.
Management
Initial Management:
For suspected EC, immediate management involves dietary modification, often an elemental or amino acid-based formula, particularly in infants
For EoE, initial management often involves dietary elimination based on allergy testing or empirical elimination diets (e.g., removing top 6 allergens).
Medical Management:
Eosinophilic Colitis: Dietary elimination therapy is the mainstay, with elemental formulas being highly effective
Oral corticosteroids may be used for severe, refractory cases
Topical steroids or mesalamine are generally not effective
Eosinophilic Esophagitis: Dietary elimination is first-line
Topical swallowed fluticasone or budesonide is the cornerstone of medical therapy to reduce eosinophilic inflammation
Oral corticosteroids are reserved for severe cases or those refractory to topical therapy
Proton pump inhibitors (PPIs) may be used, especially if there is a suspicion of GERD overlap, but their efficacy in EoE alone is debated
Biologics (e.g., dupilumab) are emerging therapies for refractory EoE.
Surgical Management:
Surgery is rarely indicated for either condition
In rare cases of EC with toxic megacolon or perforation, surgical intervention may be necessary
For EoE, stricture dilation may be required for symptomatic esophageal strictures, performed endoscopically.
Supportive Care:
Nutritional support is critical for both conditions to ensure adequate growth and development
Monitor hydration status closely
Educate parents/caregivers on dietary management and recognition of symptoms
Regular follow-up with pediatric gastroenterology and allergy specialists is essential.
Complications
Early Complications:
Eosinophilic Colitis: Severe dehydration, electrolyte imbalance, anemia due to bleeding, toxic megacolon
Eosinophilic Esophagitis: Esophageal food impaction, dehydration (due to inability to swallow).
Late Complications:
Eosinophilic Colitis: Chronic malabsorption, failure to thrive, stricture formation (rare)
Eosinophilic Esophagitis: Esophageal strictures, esophageal remodeling, long-term dysphagia, malnutrition.
Prevention Strategies:
Early recognition and diagnosis, adherence to dietary management, prompt initiation of appropriate medical therapy
Close monitoring for growth and nutritional status
Comprehensive allergy workup and avoidance of identified triggers.
Key Points
Exam Focus:
Distinguish EC from EoE based on primary site of inflammation (colon vs
esophagus)
Recognize that peripheral eosinophilia is not always present in EC
Understand dietary elimination and topical steroids as first-line therapies for EoE
Recall the typical age groups affected and common co-morbidities (atopy).
Clinical Pearls:
In infants with unexplained rectal bleeding and fussiness, consider allergic proctocolitis or EC
Persistent dysphagia or food refusal in a child with a history of atopy should raise suspicion for EoE
Endoscopic biopsy is mandatory for diagnosis in both conditions
Recognize that symptoms can overlap significantly with other GI disorders.
Common Mistakes:
Misdiagnosing EC as infectious colitis and delaying dietary intervention
Attributing EoE symptoms solely to GERD and not performing esophageal biopsies
Inadequate biopsy sampling leading to missed diagnosis of eosinophilic infiltration
Not considering underlying atopy as a significant contributing factor in both conditions.