A 90-year-old man presented with increasing fatigue over the previous two to three months. His daughter reported that he was fatigued with simple activities of daily living. The patient had not been seen by a physician for approximately 10 years. He reported a decreased appetite and mild dyspnea on exertion, but no chest pain. He had no symptoms of depressed mood. He had a history of poststreptococcal glomerulonephritis when he was a teenager, but no other medical conditions.

On physical examination, his blood pressure and pulse while sitting were normal. He had pallor and skin turgor appropriate for an older person. Cardiac and pulmonary examination findings were normal. He had no cyanosis in the extremities; however, his fingernails were deformed (Figures 1 and 2).

Question

Discussion

The answer is A: iron deficiency anemia. Spoon-shaped nails (koilonychia) are often indicative of a systemic illness. Iron deficiency anemia is the most common cause of isolated koilonychia.¹ Patients with iron overload, as in hemochromatosis, may also develop koilonychia.² A complete blood count and ferritin level should be ordered for patients with koilonychia to rule out iron abnormalities. Koilonychia can also be caused by occupational exposure to solvents or by chronic trauma,³ and it is a normal physiologic finding in infants.² Other common signs and symptoms of iron deficiency anemia include weakness and fatigue, pale skin, chest pain or palpitations, dizziness, and pica (craving for ice or dirt).

Onychomycosis, a fungal nail infection, commonly affects the toenails but can also affect the fingernails. Fungi from the skin invades the nail bed, creating the appearance of onycholysis, hyperkeratosis, and yellow streaks.² Proximal subungual onychomycosis, which appears as fungal hyphae in the deeper layers of the nail plate, is more common in patients who are immunocompromised and requires systemic treatment.

Most patients with psoriasis (80% to 90%) will develop onychodystrophy as a result of psoriatic involvement of the nail bed or nail matrix.^2,4 The classic presentation is a pitted appearance of the fingernails. Patients may also have subungual hyperkeratosis and onycholysis.⁴

Squamous cell carcinoma, a proliferating, erythematous mass, originates from the surrounding tissues and may be mistaken for onychomycosis.² There should be a high index of suspicion for squamous cell carcinoma when treatment for onychomycosis is ineffective. A biopsy confirms the diagnosis.