Upper and Lower Endoscopy Should Be Performed
This 51-year-old male with confirmed iron deficiency anemia (hemoglobin 11.0, MCV 75, ferritin 10) requires both upper endoscopy with duodenal biopsy and colonoscopy to identify the source of blood loss or malabsorption, as gastrointestinal pathology—including malignancy—is the primary concern in adult men with IDA. 1
Rationale for Dual Endoscopy
All adult men with iron deficiency anemia should undergo both upper and lower gastrointestinal investigation unless a clear alternative cause (such as coeliac disease or carcinoma) is identified during initial evaluation 1
Gastrointestinal blood loss is the most common cause of IDA in adult men and postmenopausal women, with asymptomatic colonic and gastric carcinoma being of prime concern 1
Dual pathology (significant bleeding sources in both upper and lower GI tracts) occurs in 1-10% of patients, with increasing likelihood in older patients 1
At age 51, this patient is at increased risk for gastrointestinal malignancy, making comprehensive evaluation essential 1, 2
Upper Endoscopy with Specific Testing
Upper endoscopy should include duodenal biopsies for coeliac disease screening, as this is a quality standard for all patients with IDA 1
Coeliac serology (tissue transglutaminase antibody) should ideally be obtained before endoscopy, but if unavailable, duodenal biopsies should still be taken 1
If coeliac serology is negative, duodenal biopsies may be omitted unless other features suggest coeliac disease, though obtaining them remains reasonable practice 1
Upper endoscopy can identify gastric cancer, peptic ulcer disease, angiodysplasia, and other upper GI sources of blood loss 1
Colonoscopy Is Essential
Colonoscopy (or CT colonography as an alternative) is mandatory to exclude colorectal cancer and polyps 1
The patient has never had colonoscopy and is at the appropriate age for screening regardless of anemia 1
Flexible sigmoidoscopy alone is insufficient unless colonoscopy resources are limited, and only if digital rectal examination is negative without changed bowel habit or rectal bleeding 1
Why Not Start with Oral Iron or H. pylori Testing Alone?
While all patients with IDA should receive iron supplementation, this should not delay or replace gastrointestinal investigation 1
Iron therapy alone without identifying the underlying cause risks missing malignancy and allows continued blood loss 1
The absence of GI symptoms does not reduce the need for investigation, as symptoms rarely correlate with investigation findings 1
Helicobacter pylori testing may be considered as part of the evaluation but should not replace endoscopic visualization 1
Concurrent Management
Oral iron supplementation should be initiated immediately (ferrous sulfate 200 mg three times daily or equivalent) to correct anemia and replenish stores, but this does not obviate the need for investigation 1, 3
Iron therapy should continue for three months after correction of anemia to replenish body stores 1
The hemoglobin should rise by 2 g/dL after 3-4 weeks; failure to respond suggests continued blood loss, malabsorption, or misdiagnosis 1
Common Pitfalls to Avoid
Do not attribute IDA to blood donation alone without completing GI investigation, as this patient donates only twice yearly and has no other obvious explanation 1
Do not assume NSAID use or aspirin is the sole cause until GI investigations are completed, as these patients have similar rates of GI malignancy 1
Do not delay investigation waiting for response to iron therapy in adult men, as this risks missing time-sensitive diagnoses like cancer 1, 2