Fungal nail infections account for half of all causes of nail changes (onychodystrophy). The other half can be attributed to conditions such as onychogryphosis (secondary nail thickening), psoriasis and lichen planus. Health care providers vary in their ability to correctly predict fungal toenail infections which can be confirmed by simple microscopy, fungal culture, or histology. Systemic antifungals indicated for moderate to severe nail infection can result in a variety of drug-drug interactions and confer increased risk for heart and liver failure. Confirming a fungal infection can prevent unnecessary treatment with avoidable harms and guide the diagnosis of other possible causes. For more information:
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