Workup for Confirmed Iron Deficiency Anemia in a 30-Year-Old Male
A 30-year-old male with confirmed iron deficiency anemia requires urgent bidirectional endoscopy (gastroscopy and colonoscopy) to exclude gastrointestinal malignancy and other pathology, along with coeliac disease screening and urinalysis. 1
Initial Clinical Assessment
Detailed History
Take a comprehensive history focusing on:1
- Dietary patterns: Assess for vegetarian/vegan diet or inadequate iron intake
- Medication use: NSAIDs, aspirin, anticoagulants (these should not deter investigation) 1
- Gastrointestinal symptoms: Though symptoms rarely correlate with findings, document any upper or lower GI complaints 1
- Family history: Bleeding disorders, telangiectasia, coeliac disease, or GI malignancies 1
- Blood loss: Any history of overt bleeding from any source
Essential Initial Investigations
The following tests should be performed immediately: 1
Urinalysis or urine microscopy - to exclude renal tract bleeding as a source 1
Coeliac disease screening - found in 3-5% of IDA cases 1
- Serological testing with tissue transglutaminase antibody (IgA type) plus total IgA level
- Alternatively, obtain small bowel biopsies during gastroscopy 1
Complete blood count review - evaluate MCV, red cell distribution width (RDW), and blood film 1
Gastrointestinal Investigation
Bidirectional Endoscopy (First-Line)
Both gastroscopy and colonoscopy should be performed as first-line investigations in men with newly diagnosed IDA. 1 This is critical because:
- Upper GI endoscopy reveals a cause in 30-50% of patients 1
- Dual pathology (lesions in both upper and lower GI tract) occurs in 10-15% of cases 1
- GI malignancy risk necessitates urgent investigation 1
During gastroscopy: 1
- Obtain small bowel biopsies even if mucosa appears normal (to screen for coeliac disease)
- Do not accept oesophagitis, erosions, or peptic ulcer as the sole cause without also investigating the lower GI tract 1
For colonoscopy: 1
- Complete colonoscopy is preferred over barium enema as it allows visualization of angiodysplasia and tissue biopsy 1
- If colonoscopy is not suitable, CT colonography is a reasonable alternative 1
Important Caveat
Even if upper endoscopy reveals carcinoma or coeliac disease, still proceed with lower GI investigation unless the upper GI finding definitively explains the IDA, due to the 10-15% dual pathology rate. 1
If Initial Endoscopy is Negative
Further Investigation Criteria
Additional investigation is warranted if: 1
- Inadequate response to iron replacement therapy (Hb rise <10 g/L within 2 weeks)
- Recurrent IDA after initial correction
- Transfusion-dependent anemia
Small Bowel Investigation
Capsule endoscopy is the preferred test for examining the small bowel because it is highly sensitive for mucosal lesions. 1 CT/MR enterography may be considered in those not suitable for capsule endoscopy and are complementary for assessing inflammatory and neoplastic disease. 1
Small bowel radiology is rarely useful unless the history suggests Crohn's disease. 1
When to Stop Further Investigation
After a negative capsule endoscopy of acceptable quality, further GI investigation is only needed if there is ongoing IDA despite iron replacement therapy. 1
Special Considerations for Young Males
While dietary deficiency can occur, a positive dietary history should not be presumed as the cause, and full GI investigation is still required. 1 In a 30-year-old male without obvious non-GI blood loss, the threshold for complete investigation should be low given the risk of underlying pathology including malignancy. 1
Concurrent Iron Replacement
Iron replacement therapy should not be deferred while awaiting investigations unless colonoscopy is imminent (to avoid obscuring blood in stool). 1 Start with: