In a 27-year-old male with elevated alanine aminotransferase, low serum iron, high total iron-binding capacity, and transferrin saturation of 15%, is iron-deficiency anemia a concern?

Iron Deficiency Anemia in a 27-Year-Old Male with Transferrin Saturation of 15%

Yes, a transferrin saturation of 15% in a 27-year-old male is absolutely diagnostic of iron deficiency and warrants immediate investigation and treatment. 1

Why This Is Iron Deficiency

Your patient's transferrin saturation of 15% falls well below the diagnostic threshold of 16–20% that confirms absolute iron deficiency in adults. 1, 2 The combination of:

• Low serum iron (54 µg/dL)
• Elevated TIBC (361 µg/dL)
• Low transferrin saturation (15%)

...creates the classic triad that definitively establishes iron deficiency, reflecting depleted iron stores and the body's compensatory attempt to maximize iron-binding capacity. 1, 2

The elevated TIBC is particularly telling—it increases specifically when serum iron and stored iron are low, representing upregulated transferrin production to capture any available iron. 2 A transferrin saturation below 16% has 93% specificity for true iron deficiency. 1

Critical Next Step: Obtain Ferritin

You must measure serum ferritin immediately to quantify iron stores and guide treatment intensity. 1, 3

• If ferritin < 30 ng/mL: Confirms absolute iron deficiency with depleted stores 1, 3
• If ferritin 30–100 ng/mL: Still indicates iron deficiency requiring treatment 1
• If ferritin > 100 ng/mL with TSAT 15%: Would suggest functional iron deficiency from occult inflammation 1

Your patient's CRP is <3 mg/L (normal), which rules out significant inflammation and means ferritin will accurately reflect true iron stores rather than being falsely elevated by acute-phase response. 1, 2

Mandatory Gastrointestinal Investigation

Iron deficiency in young men is uncommon but when found warrants the same investigational algorithm as for older people—specifically, evaluation for gastrointestinal pathology including malignancy. 4 The British Society of Gastroenterology explicitly states that confirmed iron deficiency in young men has a considerably higher yield of GI pathology than in women of the same age. 4

Required workup includes:

• Upper endoscopy with duodenal biopsy to exclude celiac disease (3–5% prevalence in iron-deficiency anemia) 2
• Colonoscopy to exclude colonic sources of occult bleeding 4
• Celiac serology (tissue transglutaminase antibody) 4
• Stool for occult blood 2
• Assessment for NSAID use or other medications causing GI blood loss 2

Do not dismiss this as "just dietary" in a young male—the elevated ALT (80 U/L) raises additional concern for underlying liver pathology or celiac disease that could impair iron absorption. 4

Additional Laboratory Tests Needed

Beyond ferritin, obtain:

• Complete blood count with hemoglobin, hematocrit, MCV, and reticulocyte count to assess anemia severity and red-cell indices 1, 2
• Comprehensive metabolic panel to calculate eGFR, as the mildly elevated uric acid (5.7 mg/dL) may signal early renal dysfunction affecting iron metabolism 2
• Hepatitis panel and liver ultrasound given the elevated ALT 4

Treatment Algorithm

Step 1: Initiate Oral Iron While Investigating

Start ferrous sulfate 325 mg daily or on alternate days (alternate-day dosing improves absorption and reduces GI side effects). 1, 3 Administer on an empty stomach at least 1 hour before or 2 hours after meals. 2

Step 2: Reassess in 4–8 Weeks

Repeat iron panel (ferritin, TSAT) and CBC 4–8 weeks after starting oral iron. 1 Expect hemoglobin to rise by 1–2 g/dL if treatment is effective. 1

Step 3: Switch to IV Iron If:

• No hematologic response after 4–8 weeks of adequate oral therapy 1, 2
• GI intolerance to oral iron (nausea, constipation) 1, 3
• Malabsorption identified (celiac disease, IBD) 1, 3
• Ongoing blood loss that exceeds oral replacement capacity 1

Intravenous options include ferric carboxymaltose (up to 1,000 mg single dose), iron sucrose, or low-molecular-weight iron dextran. 2

Treatment Targets:

• Ferritin ≥ 30–45 ng/mL (without inflammation) or ≥ 100 ng/mL (if inflammation present) 1
• Transferrin saturation ≥ 20% to ensure adequate iron for erythropoiesis 1, 3

Common Pitfalls to Avoid

1. Do not rely on "normal" serum iron alone—serum iron has high day-to-day variability, diurnal fluctuation, and is affected by recent meals. It is an unreliable marker. 1, 2

2. Do not skip GI evaluation in young men—the British Society of Gastroenterology is explicit that young men with confirmed iron deficiency require the same investigational rigor as older patients because pathology yield is high. 4

3. Do not measure iron studies within 4 weeks of IV iron if you eventually use parenteral therapy—circulating iron interferes with assays and produces falsely elevated results. 1

4. Do not assume dietary insufficiency—while possible, iron deficiency in a 27-year-old male eating a typical Western diet is uncommon without an underlying pathologic cause (GI bleeding, malabsorption, or chronic disease). 4, 2

The elevated ferritin (if >100 ng/mL when you measure it) combined with low TSAT would indicate functional iron deficiency from occult inflammation, but your normal CRP makes this less likely. More probable is absolute iron deficiency with depleted stores requiring both treatment and identification of the source of loss. 1, 3