Duodenitis

Duodenitis is inflammation of the duodenal mucosa (bulb and second part), seen at endoscopy as erythema, oedema, friability, or erosions, and confirmed by histology as infiltration with acute or chronic inflammatory cells, villous changes, or gastric metaplasia. The endoscopic and histological findings correlate poorly with symptoms, and the finding is often incidental.

• Prevalence: duodenal erythema or erosions are found in about 5 to 15% of upper endoscopies, and are more frequent in patients with Helicobacter pylori infection and NSAID use.
• Causes:
  • Helicobacter pylori infection (with gastric metaplasia in the duodenal bulb, a major cause of duodenal inflammation and ulcers, with infection in up to 50 to 90% of duodenitis in endemic regions).
  • NSAIDs and aspirin, alcohol, smoking, and hyperacidity states (Zollinger-Ellison syndrome, G cell hyperplasia).
  • Coeliac disease (intraepithelial lymphocytosis and villous atrophy), Crohn disease, giardiasis and other infections (cytomegalovirus, strongyloidiasis, cryptosporidium, tuberculosis), eosinophilic duodenitis, and common variable immunodeficiency.
  • Medicines: olmesartan (sprue like enteropathy), mycophenolate, methotrexate, NSAIDs, and immune checkpoint inhibitors.
  • Others: ischaemia, radiation, bile reflux, graft-versus-host disease, vasculitis, and sarcoidosis.
• Many patients have no symptoms. Duodenitis is part of the spectrum of peptic disease, and may lead to duodenal ulcer. In the absence of Helicobacter pylori and NSAIDs, further workup for coeliac disease and other causes is needed.
• Complications: duodenal ulcer, upper gastrointestinal bleeding, stricture and gastric outlet obstruction (rare), malabsorption (in coeliac disease and other enteropathies), and anaemia.

• Epigastric pain or burning, often 1 to 3 hours after meals or at night, and relieved by food or antacids (as with duodenal ulcer pain), bloating, nausea, early satiety, and belching. Symptoms are non-specific and overlap with functional dyspepsia.
• Features of underlying causes: diarrhoea, weight loss, steatorrhoea, anaemia, and dermatitis herpetiformis (coeliac disease); diarrhoea and abdominal pain with extraintestinal features (Crohn disease); travel history with bloating and diarrhoea (giardiasis); atopy and food impaction (eosinophilic disease); and medicine history (NSAIDs, olmesartan).
• Bleeding: melaena, haematemesis, anaemia.
• Examination: epigastric tenderness, pallor, or normal.
• Differential diagnosis: peptic ulcer disease, functional dyspepsia, gastritis, gastro oesophageal reflux disease, biliary and pancreatic disease, coeliac disease, giardiasis, Crohn disease, gastric or duodenal cancer, ampullary disease, and Zollinger-Ellison syndrome.
• Red flags: haematemesis, melaena, weight loss, persistent vomiting, dysphagia, anaemia, a palpable mass, jaundice, age over 55 years with new dyspepsia, chronic diarrhoea, family history of gastric cancer, multiple or recurrent ulcers (consider gastrin secreting tumour), and refractory symptoms.

• Upper endoscopy with duodenal biopsies: the diagnostic test, indicated for alarm features, persistent dyspepsia in patients over 55 years, anaemia, suspected malabsorption, or failure of empirical therapy. Take at least 4 biopsies from the second part of the duodenum and 1 or 2 from the bulb for histology (villous architecture, intraepithelial lymphocytes, eosinophils, neutrophils, Helicobacter pylori, giardia, and viral inclusions), and antral and body gastric biopsies.
• Test for Helicobacter pylori (urea breath test or stool antigen test, after 2 weeks off proton pump inhibitors and 4 weeks off antibiotics, or by biopsy).
• Coeliac serology (tissue transglutaminase IgA with total IgA) on a gluten containing diet in all patients with duodenal lymphocytosis or villous atrophy, anaemia, or diarrhoea.
• Stool Giardia antigen or polymerase chain reaction, and stool tests for parasites and Strongyloides serology in people from endemic areas.
• Blood tests: full blood count, ferritin, vitamin B12, folate, iron studies, C-reactive protein, liver tests, calcium, and fasting serum gastrin (off proton pump inhibitors for 1 to 2 weeks, if possible) when ulcers are multiple, atypical, recurrent or refractory.
• Review medicines (NSAIDs, olmesartan, mycophenolate, immune checkpoint inhibitors).
• Imaging (CT or MR enterography) for suspected Crohn disease or other small bowel disease.

• Treat the cause, and relieve symptoms:
  • Stop NSAIDs where possible (use paracetamol 1 g orally 6 hourly, maximum 4 g per day), reduce alcohol, and stop smoking.
  • Acid suppression with a proton pump inhibitor: omeprazole 20 to 40 mg orally once daily (or esomeprazole 20 to 40 mg, lansoprazole 30 mg, pantoprazole 40 mg) before breakfast for 4 to 8 weeks. Healing is expected in more than 90%. Continue longer for ongoing NSAID or aspirin use, and in high risk patients.
  • Helicobacter pylori eradication when positive: a proton pump inhibitor twice daily, amoxicillin 1 g twice daily, and clarithromycin 500 mg twice daily for 14 days (where clarithromycin resistance is low), or bismuth quadruple therapy for 10 to 14 days (a proton pump inhibitor twice daily, bismuth subcitrate 120 mg 4 times daily, tetracycline 500 mg 4 times daily, and metronidazole 400 to 500 mg 3 to 4 times daily), which is preferred where resistance is high or after previous macrolide use. Test for cure at least 4 weeks after antibiotics.
  • Antacid or alginate for breakthrough symptoms (calcium carbonate 500 to 1000 mg as needed, or sodium alginate and potassium bicarbonate 10 to 20 mL after meals), and sucralfate 1 g 4 times daily for 4 to 8 weeks in selected patients.
  • Famotidine 20 mg orally twice daily or 40 mg at night as an alternative to a proton pump inhibitor, with less effect.
• Specific causes:
  • Coeliac disease: strict lifelong gluten free diet, nutrient replacement (iron, folate, B12, vitamin D, calcium), and dietitian support, with repeat serology at 6 to 12 months, and bone density assessment.
  • Giardiasis: tinidazole 2 g orally once, or metronidazole 400 mg orally 3 times daily for 5 days (child 5 mg/kg 3 times daily), or nitazoxanide 500 mg twice daily for 3 days.
  • Strongyloidiasis: ivermectin 200 micrograms/kg orally once daily for 2 days, repeated after 2 weeks in some regimens, especially before immunosuppressive therapy.
  • Medicine induced enteropathy (olmesartan and others): stop the drug (changing to another angiotensin receptor blocker or antihypertensive), with improvement over weeks to months.
  • Crohn disease: specialist treatment (corticosteroids, immunomodulators, biologics).
  • Eosinophilic duodenitis: dietary elimination, topical or systemic corticosteroids (budesonide or prednisolone 20 to 40 mg daily, tapered) in specialist care.
  • Zollinger-Ellison syndrome: high dose proton pump inhibitor (omeprazole 60 mg daily, adjusted to control acid output), and tumour localisation and surgery in specialist care.
  • Cytomegalovirus: ganciclovir 5 mg/kg IV 12 hourly in specialist care for severe disease in immunosuppressed patients.
  • Bleeding: resuscitation, intravenous pantoprazole or omeprazole 80 mg bolus then 8 mg per hour for 72 hours for high risk lesions, endoscopic haemostasis, and transfusion for haemoglobin below 70 g/L.
• Iron deficiency: ferrous sulphate 200 mg (65 mg elemental iron) orally once daily or on alternate days for 3 months after normalisation of haemoglobin. Use intravenous iron (ferric carboxymaltose 500 to 1000 mg) for malabsorption or intolerance.
• Special groups:
  • Pregnancy: avoid NSAIDs, use antacids, alginate and omeprazole 20 mg daily or famotidine for symptoms, and defer Helicobacter pylori eradication until after delivery unless there is a complicated ulcer.
  • Children: treat with a proton pump inhibitor (omeprazole 0.7 to 3.3 mg/kg per day) and test for coeliac disease and Helicobacter pylori. Eradicate Helicobacter pylori only if ulcer or erosions with symptoms are proven.
  • Elderly: review NSAID, aspirin, and anticoagulant use, give gastroprotection, and investigate for malignancy.
  • Immunosuppressed: low threshold for biopsy and testing for opportunistic infection.
  • Renal impairment: avoid NSAIDs, adjust antibiotic doses, and avoid aluminium containing sucralfate in long term use.
• Follow up: review at 4 to 8 weeks, confirm Helicobacter pylori eradication, and repeat endoscopy for ulcers, persistent symptoms, abnormal histology, or alarm features. Refer to a gastroenterologist for refractory symptoms, villous atrophy, suspected Crohn disease or Zollinger-Ellison syndrome, and unexplained anaemia.