Gastroenteritis (Stomach Flu)
This is an inflammation of the stomach and intestines, typically caused by a viral or bacterial infection.

• Common Causes: Viruses (e.g., rotavirus, norovirus, adenovirus), bacteria (e.g., Salmonella, E. coli, Campylobacter), or parasites.

• Symptoms:

  • Diarrhea (loose, watery stools, may be frequent).

  • Vomiting.

  • Abdominal pain or cramping.

  • Fever.

  • Nausea.

  • Loss of appetite.

• Main Concern: Dehydration, especially in younger individuals, due to fluid loss from diarrhea and vomiting.

  • Signs of dehydration: Dry mouth, decreased urine output (fewer wet diapers), sunken eyes, no tears when crying, lethargy, sunken fontanelle (soft spot) in infants.

• Management:

  • Focus on fluid replacement: Oral Rehydration Solution (ORS) is crucial. Give small, frequent sips. Breastfeeding or formula feeding should continue.

  • Continue feeding with an age-appropriate diet as tolerated; avoid sugary drinks and very fatty foods.

  • Medications are usually not needed for viral gastroenteritis. Antibiotics may be used for some bacterial infections. Antidiarrheal and antiemetic medications are generally not recommended for young individuals unless prescribed by a doctor.

  • Good hygiene (handwashing) to prevent spread.

  • Severe dehydration may require intravenous (IV) fluids in a hospital setting.

Constipation
This refers to infrequent bowel movements, difficulty passing stools, or passing hard, dry stools.

• Causes: Diet low in fiber, insufficient fluid intake, withholding stools (due to previous painful experience or being busy), changes in routine, certain medications, or underlying medical conditions (less common).

• Symptoms:

  • Fewer than three bowel movements per week (can vary).

  • Stools are hard, dry, and difficult or painful to pass.

  • Straining during bowel movements.

  • Abdominal pain or discomfort, bloating.

  • Small amounts of liquid stool (overflow soiling or encopresis) may leak around a hard impacted stool.

• Management:

  • Dietary changes: Increase fiber intake (fruits, vegetables, whole grains). Increase fluid intake (water).

  • Behavioral changes: Encourage regular toilet sitting times (e.g., after meals). Promote a relaxed toileting environment. Do not punish for accidents.

  • Medications (if prescribed by a doctor): Stool softeners or laxatives may be used for a period to help clear impacted stool and establish regular bowel habits.

  • Address any underlying fear of painful defecation.

Gastroesophageal Reflux (GER) / Gastroesophageal Reflux Disease (GERD)

• GER: The passage of stomach contents back up into the esophagus (food pipe). It is common and often normal in infants (“spitting up”). Usually resolves as the individual matures.

• GERD: When GER causes troublesome symptoms or complications.

• Symptoms of GER in Infants:

  • Frequent spitting up or vomiting, especially after feeds.

  • Usually effortless and non-forceful.

  • Infant is generally comfortable and growing well (“happy spitter”).

• Symptoms suggestive of GERD (more problematic):

  • Poor weight gain or weight loss.

  • Irritability, excessive crying, especially during or after feeds.

  • Feeding refusal or aversion.

  • Arching of the back during or after feeds.

  • Respiratory problems (e.g., chronic cough, wheezing, recurrent pneumonia) due to aspiration of refluxed contents.

  • Heartburn (older individuals may complain of chest pain or a burning sensation).

  • Esophagitis (inflammation of the esophagus).

• Management of GER (simple reflux):

  • Conservative measures: Smaller, more frequent feeds. Burping well during and after feeds. Keeping the infant upright for 20-30 minutes after feeds.

  • Thickening feeds (e.g., adding rice cereal to formula, if advised by a doctor).

• Management of GERD:

  • Lifestyle and feeding modifications as above.

  • Medications (if prescribed):

    • Acid-suppressing medications (e.g., H2 blockers like ranitidine, or proton pump inhibitors – PPIs – like omeprazole) to reduce stomach acid and allow the esophagus to heal.

  • Rarely, surgery (e.g., Nissen fundoplication) may be considered for severe, refractory GERD with significant complications.

Appendicitis
(Also covered under surgical conditions, relevant here as a GI tract inflammation)
This is an inflammation of the appendix, a small, finger-like pouch attached to the large intestine.

• Symptoms:

  • Pain often starting around the navel, then moving to the right lower quadrant of the abdomen.

  • Nausea, vomiting.

  • Loss of appetite.

  • Fever.

  • Tenderness when the right lower abdomen is pressed.

  • Pain may worsen with movement, coughing, or deep breaths.

• Main Concern: Rupture of the appendix, leading to peritonitis (infection of the abdominal lining), which is a serious complication.

• Management: Surgical removal of the appendix (appendectomy). Antibiotics are also given.

Celiac Disease
An autoimmune disorder where ingestion of gluten (a protein found in wheat, barley, and rye) leads to damage in the small intestine.

• Symptoms (can be highly variable):

  • Digestive symptoms: Chronic diarrhea, abdominal pain and bloating, constipation, vomiting, pale, foul-smelling, or fatty stools (steatorrhea).

  • Non-digestive symptoms: Failure to thrive or poor weight gain, short stature, delayed puberty, iron-deficiency anemia (resistant to iron therapy), fatigue, irritability, skin rash (dermatitis herpetiformis), dental enamel defects, bone or joint pain.

• Diagnosis:

  • Blood tests for specific antibodies (e.g., anti-tissue transglutaminase IgA – tTG-IgA).

  • Genetic testing for HLA-DQ2/DQ8 (absence makes celiac disease highly unlikely).

  • Endoscopy with small intestinal biopsy is the gold standard for confirming the diagnosis (shows villous atrophy).

• Management: Lifelong strict adherence to a gluten-free diet. This involves avoiding all foods containing wheat, barley, rye, and contaminated oats. Nutritional counseling by a dietitian is essential.

Inflammatory Bowel Disease (IBD)
A term for two chronic inflammatory conditions of the gastrointestinal tract: Crohn’s disease and Ulcerative Colitis.

• Crohn’s Disease: Can affect any part of the GI tract from mouth to anus, often in patches. Inflammation can be transmural (affecting all layers of the bowel wall).

• Ulcerative Colitis (UC): Affects only the colon (large intestine) and rectum, usually starting in the rectum and extending proximally in a continuous manner. Inflammation is typically limited to the innermost lining (mucosa).

• Symptoms (vary depending on type, location, and severity):

  • Persistent diarrhea (may be bloody, especially in UC).

  • Abdominal pain and cramping.

  • Rectal bleeding.

  • Urgency to defecate.

  • Weight loss, poor growth, delayed puberty.

  • Fever, fatigue.

  • Extraintestinal manifestations (e.g., joint pain, skin rashes, eye inflammation).

• Diagnosis: Combination of clinical evaluation, blood tests (for inflammation, anemia), stool studies (to rule out infection), endoscopy (colonoscopy, upper endoscopy) with biopsies, and imaging studies (e.g., MRI, CT).

• Management (aims to induce and maintain remission, improve quality of life):

  • Medications:

    • Anti-inflammatory drugs (e.g., aminosalicylates like mesalamine).

    • Corticosteroids (for acute flare-ups).

    • Immunomodulators (e.g., azathioprine, methotrexate) to suppress the immune system.

    • Biologic therapies (e.g., anti-TNF agents like infliximab, adalimumab) that target specific inflammatory pathways.

  • Nutritional support (e.g., exclusive enteral nutrition for Crohn’s disease).

  • Surgery may be needed for complications or disease refractory to medical therapy (e.g., removal of diseased bowel segments).

Functional Abdominal Pain
Recurrent abdominal pain without an identifiable organic cause after appropriate medical evaluation.

• Very common. The pain is real, but not due to a structural or biochemical abnormality.

• May be associated with stress, anxiety, or altered gut sensitivity.

• Management:

  • Reassurance after a thorough evaluation has ruled out serious underlying disease.

  • Identifying and managing stress or anxiety triggers.

  • Cognitive-behavioral therapy (CBT) or other psychological approaches.

  • Dietary modifications (e.g., identifying food intolerances, sometimes a trial of a low-FODMAP diet under guidance).

  • Focus on coping strategies and maintaining normal activities as much as possible.