Chronic hand infections.

Chronic infections of the hand are uncommon, and a high index of suspension is required for their early diagnosis. These can be grouped based on the microorganism. Mycobacterial infections include tuberculosis, atypical mycobacterial infections, and leprosy. Other bacterial infections include actinomycosis, cat-scratch disease, syphilis, tularemia, bacillary angiomatosis, and actinomycetoma. Fungal infections may be classified as cutaneous (affecting the skin, the paronychia or nail plate), subcutaneous (mainly lymphocutaneous sporotrichosis and dermatiaceous infections), and deep fungal infections. Each type of deep fungal infection has a "classic" presentation and this is emphasized. Finally, common chronic viral infections of the hand include warts and orf.