What condition is characterized by pitting on the nails?

The condition characterized by pitting on the nails is nail psoriasis. Pitting occurs because psoriasis affects the growth cycle of the nail matrix, leading to the formation of small depressions or pits on the nail surface. This condition often manifests alongside skin psoriasis, which may cause scaly patches and inflammation. The pitting can vary in depth and size, contributing to the nail’s irregular appearance.

In contrast, nail fungus typically results in discoloration, thickening, and deterioration of the nail without the characteristic pitting associated with psoriasis. Paronychia, which involves inflammation of the skin around the nail, usually leads to swelling, redness, and possible pus, rather than changes to the nail surface. Onycholysis refers to the separation of the nail from the nail bed, which can cause the nail to appear lifted or discolored but does not involve pitting. Understanding these distinctions helps in recognizing nail health issues accurately.