Pitted keratolysis, also known as keratolysis sulcata, is a bacterial infection of the soles of the feet or, less commonly, the palms of the hands. Pitted keratolysis is easily identified by its shallow, crater-like pits. It is generally caused by coryneform bacteria, though several other strains of bacteria have been discovered in the lesions, including Micrococcus sedentarius, Actinomyces keratolytica and Dermatophilus congolensis. The tell-tale crater-like pitting is a direct result of the proteolytic enzymes manufactured by the bacteria digesting the keratin, which is a resilient protein that gives the skin its strength and toughness. It is also important to note that pitting keratolysis is non-contagious.