In a stable adult with mild anemia (Hb 123 g/L), normal complete blood count and renal function, modest CRP elevation, and mild right upper eyelid fullness extending to the nasolabial fold without pain or erythema, what is the most likely diagnosis and recommended next steps?

Clinical Assessment: Mild Facial Asymmetry with Mild Anemia and Elevated CRP

This clinical picture most likely represents early iron deficiency anemia with an unrelated benign facial anatomical variant or resolving mild sinusitis, and the patient requires iron studies, gastrointestinal evaluation, and ENT consultation to exclude structural pathology.

Interpretation of Laboratory Findings

Hematologic Pattern

• The mild anemia (Hgb 123 g/L, HCT 38%) with normal WBC and platelet counts suggests early iron deficiency or anemia of chronic disease. 1
• Iron-rich diet alone is insufficient—serum ferritin is the single most useful marker for confirming iron deficiency, with levels <30 μg/L indicating low body iron stores. 2, 3
• In the presence of inflammation (CRP 34.37 mg/L is elevated), ferritin up to 100 μg/L may still indicate iron deficiency, but ferritin >150 μg/L essentially excludes absolute iron deficiency. 3
• Transferrin saturation <20% would confirm insufficient circulating iron for erythropoiesis. 3

Inflammatory Markers

• The elevated CRP (34.37 mg/L) indicates active inflammation and can mask true iron deficiency by falsely elevating ferritin levels. 3, 4
• CRP has a negative correlation with hemoglobin concentration—higher CRP is associated with lower hemoglobin levels in chronic inflammatory states. 5, 4
• Normal ferritin (not provided in labs) does not exclude iron deficiency when inflammation is present. 6, 7

Renal and Coagulation Parameters

• Normal BUN, creatinine, and electrolytes appropriately exclude renal causes of anemia. 8
• Normal PT/PTT exclude coagulopathy as a cause of occult bleeding. 1

Facial Asymmetry Assessment

Differential Diagnosis

• Mild right upper eyelid fullness extending to the nasolabial fold without pain, erythema, or systemic symptoms is most consistent with normal anatomical variation or resolving sinusitis rather than acute infection or angioedema. 1
• The absence of pain on palpation, erythema, and stable vital signs argue strongly against acute bacterial sinusitis, dental abscess, or cellulitis. 1
• Normal IgE (77.39) and clinical course since admission make angioedema unlikely, as correctly noted. 1

ENT Evaluation Rationale

• ENT referral is appropriate to exclude maxillary-ethmoid sinusitis, occult dental pathology, or structural abnormalities that could explain the facial asymmetry. 1
• The inability to fully inspect the oral cavity due to patient non-cooperation necessitates specialist evaluation to exclude dental abscess or other intraoral pathology. 1

Mandatory Next Steps

Iron Deficiency Workup

1. Order serum ferritin, transferrin saturation, and repeat CRP immediately. 2, 3
2. If ferritin <30 μg/L (or <100 μg/L with elevated CRP) and transferrin saturation <20%, diagnose iron deficiency anemia. 3
3. All adults with confirmed iron deficiency require gastrointestinal evaluation regardless of hemoglobin level or symptom presence—30-50% will have an upper GI source and colonoscopy is mandatory as dual pathology occurs in ~10%. 2

Gastrointestinal Investigation Algorithm

• Upper endoscopy with small bowel biopsies: Screen for celiac disease (2-3% prevalence in iron deficiency) and evaluate for gastritis, ulcers, or malignancy. 1, 2
• Colonoscopy or CT colonography: Mandatory even if upper GI source is found, as dual pathology is common. 2
• Urinalysis (already done, normal) appropriately excludes urinary tract bleeding. 1

Iron Replacement Strategy

• Initiate oral iron supplementation (200 mg elemental iron daily) once iron deficiency is confirmed by ferritin testing. 1, 2
• Continue iron for 3-6 months after hemoglobin normalizes to replete stores. 2
• A hemoglobin rise ≥10 g/L within 2 weeks is highly suggestive of absolute iron deficiency, even if initial iron studies are equivocal. 1

ENT Consultation

• Proceed with ENT evaluation for complete oral cavity inspection, nasal endoscopy, and imaging (CT sinuses if indicated) to definitively characterize the facial asymmetry. 1
• Temporal artery examination should be performed to exclude giant cell arteritis, though the patient's age and clinical presentation make this unlikely. 1

Critical Pitfalls to Avoid

• Never assume normal hemoglobin excludes significant pathology—mild anemia or pre-anemic iron deficiency can indicate serious underlying disease including malignancy. 2
• Do not start empiric iron therapy without confirming iron deficiency with ferritin, as this can cause harm in thalassemia patients and delays proper diagnosis. 2
• Do not attribute anemia solely to "anemia of chronic disease" without excluding iron deficiency—combined deficiency is common when CRP is elevated. 3, 4
• Do not dismiss facial asymmetry as "normal variation" without ENT evaluation, especially when oral cavity inspection is incomplete. 1

Follow-Up Plan

• Repeat CBC after 1 week (as planned) to assess hemoglobin trend. 1
• If hemoglobin continues to decline or fails to improve with iron therapy, consider bone marrow evaluation or hematology referral. 8
• Monitor CRP to assess inflammatory burden and guide interpretation of ferritin levels. 5, 4