What diagnosis is suggested by a patient with red‑cell distribution width 16.4 %, mean platelet volume 12.7 fL, platelet distribution width 35.6 fL, erythrocyte sedimentation rate 49 mm/hr, C‑reactive protein 4.2 mg/L, serum iron 45 µg/dL, transferrin saturation 12 %, hemoglobin A1c 6.0 %, urine glucose 3+, urine epithelial cells 9 % and urine yeast 26 %?

Diagnosis: Iron Deficiency Anemia with Concurrent Inflammation and Uncontrolled Diabetes with Genitourinary Candidiasis

The laboratory profile indicates iron deficiency anemia occurring in the setting of active inflammation, combined with uncontrolled diabetes mellitus and urinary yeast infection.

Primary Hematologic Diagnosis

Iron deficiency anemia is confirmed by the combination of low serum iron (45 µg/dL), markedly reduced transferrin saturation (12.06%), elevated RDW (16.4%), and elevated inflammatory markers. 1, 2

Key Diagnostic Features Supporting Iron Deficiency

• Transferrin saturation of 12.06% is well below the diagnostic threshold of 15-20% and strongly supports iron deficiency, even in the presence of inflammation. 1, 2, 3

• The elevated RDW (16.4%) reflects anisocytosis—a mixed population of normal older red cells and smaller, hypochromic newer cells—which is characteristic of evolving iron deficiency. 2, 3, 4

• Serum iron of 45 µg/dL is significantly reduced, consistent with depleted iron stores available for erythropoiesis. 1

• The elevated MPV (12.7 fL) and PDW (35.6 fL) indicate reactive thrombocytosis, which frequently accompanies iron deficiency anemia as a secondary, non-clonal compensatory response. 3

Inflammation Complicating the Picture

The markedly elevated ESR (49 mm/hr) and elevated CRP (4.20 mg/L) indicate active inflammation, which modifies the interpretation of iron studies. 1

• In the presence of biochemical inflammation, ferritin levels up to 100 µg/L may still be consistent with iron deficiency, because ferritin is an acute-phase reactant that rises during inflammatory states. 1, 2, 3

• The diagnostic criteria for anemia of chronic disease require ferritin >100 µg/L and transferrin saturation <20%; however, your transferrin saturation of 12% with inflammation suggests a combination of true iron deficiency and anemia of chronic disease. 1, 5, 6, 7

• Inflammation causes functional iron deficiency by sequestering iron within macrophages of the reticuloendothelial system through hepcidin-mediated ferroportin blockade, restricting iron availability for erythropoiesis despite adequate stores. 5, 6, 7

Secondary Metabolic Diagnosis

The HbA1c of 6.0% indicates prediabetes or early diabetes mellitus, while urine glucose 3+ confirms uncontrolled hyperglycemia with glycosuria exceeding the renal threshold. 2

Genitourinary Infection

Urine yeast 26.40% with epithelial cells 9.10% indicates genitourinary candidiasis, which is strongly associated with uncontrolled diabetes and requires antifungal therapy. 2

• Persistent glycosuria creates a favorable environment for Candida overgrowth in the urinary tract, and this infection will not resolve without achieving glycemic control. 2

Diagnostic Workup Algorithm

Immediate Laboratory Tests Required

1. Obtain serum ferritin immediately to complete the iron panel, because ferritin is the single most specific test for iron deficiency and is essential to distinguish absolute iron deficiency from anemia of chronic disease. 1, 2, 3

2. Measure complete blood count with MCV, MCH, and MCHC to determine if microcytic hypochromic anemia is present, which would further support iron deficiency. 2, 3

3. Order absolute reticulocyte count to assess bone marrow response; a low or inappropriately normal count indicates impaired erythropoiesis from iron deficiency or inflammation. 1, 2

4. Perform stool guaiac testing to screen for occult gastrointestinal bleeding, the most common cause of iron deficiency in adults. 2, 3

Ferritin Interpretation Based on Inflammation

• If ferritin <30 µg/L: Confirms absolute iron deficiency despite inflammation. 1, 2, 3

• If ferritin 30-100 µg/L: Indicates a combination of true iron deficiency and anemia of chronic disease; proceed with iron supplementation. 1, 2

• If ferritin >100 µg/L: Suggests anemia of chronic disease predominates, but the very low transferrin saturation (12%) still indicates functional iron deficiency requiring treatment. 1, 5, 6

Investigation for Underlying Cause

All adult patients with confirmed iron deficiency require evaluation for gastrointestinal blood loss, including upper endoscopy and colonoscopy, to exclude malignancy—regardless of anemia severity. 2, 3

• Assess for malabsorption disorders (celiac disease, inflammatory bowel disease, prior gastric surgery) that impair iron absorption. 2, 3

• The elevated inflammatory markers (ESR 49, CRP 4.2) warrant investigation for chronic inflammatory conditions such as inflammatory bowel disease, rheumatologic disorders, or occult infection. 1

Treatment Recommendations

Iron Replacement Therapy

Initiate oral iron supplementation with ferrous sulfate 325 mg (65 mg elemental iron) once to three times daily between meals, and expect hemoglobin to rise approximately 1-2 g/dL every 2-4 weeks. 2, 3

• Continue iron therapy for 3-6 months after hemoglobin normalizes to replenish iron stores, and recheck hemoglobin, reticulocytes, and iron studies after 4-8 weeks. 2, 3

• Consider intravenous iron if oral therapy is not tolerated, produces inadequate response, or if severe anemia requires rapid correction. 1, 2

• In the presence of active inflammation, intravenously administered iron may be trapped in reticuloendothelial macrophages and less effective for erythropoiesis, while oral iron absorption is impaired by hepcidin upregulation. 5, 6, 7

Management of Underlying Inflammation

Treatment of the underlying inflammatory condition is the primary therapeutic approach and will improve both anemia of chronic disease and iron utilization. 5, 6, 7

• Once the inflammatory disorder is identified and controlled, the anemia typically resolves over time as hepcidin levels normalize and iron becomes available for erythropoiesis. 5, 6, 7

Diabetes and Infection Management

Achieve glycemic control with appropriate antihyperglycemic therapy to resolve glycosuria and prevent recurrent candidiasis. 2

Treat genitourinary candidiasis with oral fluconazole or topical antifungal therapy, and confirm clearance with repeat urinalysis after treatment. 2

Common Pitfalls to Avoid

• Do not dismiss iron deficiency based on "normal" ferritin in the setting of inflammation; use the higher cutoff of 45-100 µg/L depending on CRP elevation. 1, 2, 3

• Do not rely on RDW alone for diagnosis, as sensitivity is only 71% and specificity 54% in hospitalized patients with chronic disease. 4

• Do not overlook the need for gastrointestinal evaluation, as iron deficiency in adults often indicates ongoing blood loss requiring endoscopic investigation. 2, 3

• Do not assume anemia of chronic disease precludes iron supplementation; the very low transferrin saturation (12%) indicates functional iron deficiency that may respond to iron therapy even with inflammation present. 1, 5, 6