Unilateral Onychodystrophy and Puffy Fingers: Think about Carpal Tunnel Syndrome

An 87-year-old man was referred to our department for evaluation of his dystrophic left fingernails that developed progressively for the past 2 years. His past medical history included hemodialysis for 10 years for chronic renal failure. Examination of his nails revealed xanthonychia, onycholysis, Beau's lines, and marked hyperkeratosis of the nail plate involving all of his left fingernails. However, his right fingernails were not affected (Figure 1). He also had edema of the left hand associated with puffy fingers but without trophic disorders (Figure 2). Mycologic exam-ination with direct microscopy and culture of his affected nails were negative. Antinuclear antibodies (ANAs), Scl-70 (anti-topoisomerase) antibodies, anti-centromere antibodies, and anti-RNA polymerase III antibodies were all negative. Capillaroscopy showed no abnormalities. An X-ray of his left hand showed no bony abnormalities. For the past 5 years, the patient had suffered from paresthesia and numbness on the left hand in the area of the median nerve. Paresthesia, pain, burning, and tingling involved mainly the thumb, plus the index and middle fingers, but not the little finger. Carpal tunnel syndrome (CTS) was suspected. Neurologic examination and electromyography (EMG) confirmed the diagnosis of CTS of the left hand explaining his unilateral onychodystrophy. The patient was then referred to a hand surgeon for his CTS.