An 80-year-old woman is brought to the physician by her son due to fatigue. She lives alone and suffers from bilateral knee osteoarthritis, which significantly limits her mobility. Her only other medical problem is hypertension. Her medications include lisinopril, chlorthalidone, and prescription naproxen. She also takes low-dose aspirin because it is "good for the heart." Her blood pressure is 146/92 mm Hg and pulse is 78/min. The patient has conjunctival pallor. Both knees are deformed due to bony overgrowth but there is no significant effusion or erythema. Extension of both knees is limited. Her renal function, assessed 2 months ago, was normal. Which of the following is the most likely cause of pallor in this patient?

Question

An 80-year-old woman is brought to the physician by her son due to fatigue.  She lives alone and suffers from bilateral knee osteoarthritis, which significantly limits her mobility.  Her only other medical problem is hypertension.  Her medications include lisinopril, chlorthalidone, and prescription naproxen.  She also takes low-dose aspirin because it is "good for the heart."  Her blood pressure is 146/92 mm Hg and pulse is 78/min.  The patient has conjunctival pallor.  Both knees are deformed due to bony overgrowth but there is no significant effusion or erythema.  Extension of both knees is limited.  Her renal function, assessed 2 months ago, was normal.  Which of the following is the most likely cause of pallor in this patient?

Quizplus · Accepted Answer

Conjunctival pallor on physical examination is nonspecific but suggests a significant underlying anemia. Iron deficiency anemia is the most likely diagnosis in this patient given her concurrent nonsteroidal anti-inflammatory drug (NSAID) and aspirin use. Both NSAIDs and aspirin can cause gastritis and/or gastric ulcers leading to chronic gastrointestinal blood loss and depletion of iron stores. Evaluation of this patient would likely include blood counts, iron studies, and fecal occult blood testing. If iron deficiency is confirmed, especially if there is evidence of ongoing blood loss, definitive diagnosis can be obtained with upper (and usually lower) gastrointestinal endoscopy. Even mild iron deficiency should be evaluated thoroughly as low-grade gastrointestinal bleeding may herald a later catastrophic hemorrhage. Management typically includes withholding NSAIDs and aspirin and initiating antisecretory medication (proton pump inhibitors). Elderly patients may present additional challenges in evaluating acute anemia. Besides other potential comorbidities that can cause chronic anemia at baseline (eg, renal insufficiency, myelodysplastic syndromes, occult malignancy, nutritional deficiencies), a significant number of elderly patients will have a baseline anemia for which no etiology is apparent, the so-called "idiopathic anemia of ageing." They are also more likely to have additional comorbidities such as congestive heart failure or chronic lung disease, which make them poorly tolerant of even mild anemia. (Choice A) Anemia of chronic disease (anemia of chronic inflammation) is caused by suppression of red cell production by inflammatory cytokines. It commonly occurs in inflammatory arthropathies (eg, rheumatoid arthritis, lupus) but is not associated with osteoarthritis. (Choice B) Aplastic anemia is a disorder of bone marrow stem cells that is often induced by exposure to various drugs, chemicals, ionizing radiation, or viruses. It can also be idiopathic. The incidence increases with age, but it is significantly less common than iron deficiency anemia at any age. (Choice C) Although the risk of drug-induced hemolysis (eg, dapsone with G6PD deficiency) may be higher in older patients taking multiple medications, it is an uncommon cause of anemia. None of this patient's medications are strongly associated with hemolysis. (Choice D) Undiagnosed hypothyroidism is common in elderly patients and can cause a number of nonspecific symptoms including fatigue, depression, and mental status abnormalities. It can also cause anemia, but the anemia of hypothyroidism is generally mild and less likely to be apparent on examination than iron deficiency anemia. (Choice F) Although biochemical vitamin B12 deficiency, as defined by low serum B12 levels, is relatively common, overt anemia due to B12 deficiency is significantly less common. The clinician may wish to measure B12 levels, especially in a patient with macrocytic anemia. However, iron deficiency anemia is more common in elderly patients taking a combination of naproxen and aspirin. Educational objective: Nonsteroidal anti-inflammatory drugs are a common cause of iron deficiency anemia, often through chronic blood loss from the gastrointestinal tract. Iron deficiency anemia should prompt a thorough evaluation for the cause as early low-grade bleeding can herald later catastrophic hemorrhage. Elderly patients often have a low-grade chronic anemia at baseline and may not tolerate additional blood loss.

An 80-Year-Old Woman Is Brought to the Physician by Her