Internal Medicine · Year 3 · from Internal Medicine

Case 1: Iron Deficiency Anemia with Occult GI Bleeding

Patient Demographics

  • Age: 62 years
  • Sex: Male
  • Occupation: Retired firefighter

Chief Complaint

"I'm exhausted all the time and get short of breath just walking to the mailbox."

History of Present Illness

The patient presents with a 4-month history of progressive fatigue and exercise intolerance. He used to walk 2 miles daily but now becomes dyspneic after walking less than a block. He has noticed occasional lightheadedness when standing quickly and reports that his wife has commented that he "looks pale." He denies chest pain, palpitations, or syncope. He has not noticed any overt blood in his stool but admits he does not regularly inspect his bowel movements. He has also developed an unusual craving for ice, consuming several glasses of ice chips daily. Past medical history includes hypertension and osteoarthritis. He takes lisinopril and over-the-counter ibuprofen regularly for joint pain.

Vital Signs

  • Temperature: 98.4 degrees F (36.9 degrees C)
  • Blood pressure: 128/76 mmHg (sitting), 108/68 mmHg (standing)
  • Heart rate: 88 bpm (sitting), 110 bpm (standing)
  • Respiratory rate: 16/min
  • Oxygen saturation: 98% on room air

Physical Examination

General: Pale-appearing male, no acute distress at rest HEENT: Conjunctival pallor, glossitis (smooth, red tongue), angular cheilitis Cardiovascular: Tachycardic with orthostatic change, systolic flow murmur (grade 2/6 at LUSB) Pulmonary: Clear bilaterally Abdomen: Soft, non-tender, no hepatosplenomegaly, no masses Extremities: Koilonychia (spoon-shaped nails) noted on several fingers, no edema Rectal: Brown stool, guaiac positive (occult blood present) Neurologic: Alert and oriented, no focal deficits

Laboratory Findings

Complete Blood Count:

  • Hemoglobin: 7.2 g/dL (low - severe anemia)
  • Hematocrit: 22%
  • MCV: 68 fL (low - microcytic)
  • MCH: 24 pg (low)
  • MCHC: 30 g/dL (low)
  • RDW: 18.5% (elevated - anisocytosis)
  • WBC: 6,800/mcL (normal)
  • Platelets: 398,000/mcL (mildly elevated - reactive thrombocytosis)
  • Reticulocyte count: 0.8% (inappropriately low for degree of anemia)

Iron Studies:

  • Serum iron: 22 mcg/dL (low, normal 60-170)
  • TIBC: 468 mcg/dL (elevated, normal 250-370)
  • Transferrin saturation: 5% (low, calculated as iron/TIBC x 100)
  • Ferritin: 8 ng/mL (low, normal 30-300)

Peripheral Blood Smear:

  • Microcytic, hypochromic red blood cells
  • Marked anisocytosis and poikilocytosis
  • Target cells and pencil cells present
  • No schistocytes or spherocytes

Diagnosis

Severe iron deficiency anemia with likely occult gastrointestinal blood loss

Workup for Etiology

Given the patient's age, sex, and positive fecal occult blood test, gastrointestinal malignancy must be excluded:

  1. Esophagogastroduodenoscopy (EGD): Revealed 3 cm ulcerating mass in the gastric antrum; biopsies obtained
  2. Colonoscopy: Normal examination, no polyps or masses
  3. Gastric biopsy pathology: Adenocarcinoma of the stomach

Management

Immediate anemia management:

  1. Transfuse 2 units packed red blood cells (symptomatic severe anemia with hemoglobin < 7 g/dL and orthostatic hypotension)
  2. Hold ibuprofen (contributes to gastric injury and inhibits platelet function)

Iron replacement:

  1. Oral ferrous sulfate 325 mg three times daily on empty stomach (once acute bleeding controlled)
  2. Consider IV iron (iron sucrose or ferric carboxymaltose) if unable to tolerate oral iron or if rapid repletion needed before surgery

Treatment of underlying cause:

  1. Oncology referral for staging and treatment of gastric adenocarcinoma
  2. Surgical oncology consultation for potential gastrectomy
  3. PPI therapy for acid suppression

Monitoring:

  1. Reticulocyte count in 7-10 days (should peak if responding to iron)
  2. Hemoglobin in 2-4 weeks (should increase 1-2 g/dL)
  3. Continue oral iron for 3-6 months after hemoglobin normalizes to replete iron stores

Clinical Pearl

In an adult male or postmenopausal female with iron deficiency anemia, gastrointestinal blood loss must be presumed until proven otherwise, and GI malignancy must be excluded with endoscopic evaluation. The classic clinical features of iron deficiency include pica (craving for non-food substances like ice - called pagophagia), koilonychia (spoon nails), glossitis, and angular cheilitis. This patient also demonstrates the classic lab profile: low ferritin (most specific test for iron deficiency), low serum iron, high TIBC, and low transferrin saturation. The elevated platelet count (reactive thrombocytosis) is common in iron deficiency anemia due to cross-reactivity between thrombopoietin and erythropoietin.

Clinical Image

Image Description: Peripheral blood smear showing microcytic, hypochromic red blood cells characteristic of iron deficiency anemia. The red cells appear small with increased central pallor compared to normal red blood cells.

Attribution: Image from Wikimedia Commons. Licensed under CC BY-SA 4.0. Source: https://commons.wikimedia.org/wiki/File:Iron_deficiency_anemia_blood_film.jpg

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