Multiple minute digitate hyperkeratosis

Multiple minute digitate hyperkeratosis, also known as digitate keratoses, disseminated spiked hyperkeratosis, familial disseminated piliform hyperkeratosis, and minute aggregate keratosis is a rare cutaneous condition, with about half of cases being familial, inherited in an autosomal dominant fashion, while the other half are sporadic.^[1]

Multiple minute digitate hyperkeratosis is mostly a nonfollicular digitate keratosis that affects the limbs and trunk. There is no impact on the face or palmoplantar surfaces. The lesions consist of skin-colored, yellow, brown, or white spicules that range in length from 0.5 to 5.0 mm and diameter from 0.3 to 3.0 mm. Occasionally, flat-topped, dome-shaped, or crateriform papules are also present.^[2]

Multiple minute digitate hyperkeratosis may be sporadic or familial.^[2]

Histopathology reveals a stratum granulosum with varying thickness and localized orthokeratotic hyperkeratosis originating from a tented epidermis. Rarely, there have also been reports of superficial cutaneous lymphoplasmocytic infiltrates, parakeratosis, and epidermal invagination. A recurring characteristic that unites all of the cases that have been documented is the absence of follicular involvement.^[3]

Reduced keratohyaline granules with varying numbers of Odland bodies are seen under electron microscopy.^[3]

While improvements with various topical keratolytics and topical and oral retinoids have been reported, treatment is frequently ineffective or only temporary.^[2]

• Epidermis
• Skin lesion

• Pimentel, CL; Puig, L; García‐Muret, MP; Fernandez‐Figueras, MT; Alomar, A (2002). "Multiple minute digitate hyperkeratosis". Journal of the European Academy of Dermatology and Venereology. 16 (4). Wiley: 422–424. doi:10.1046/j.1468-3083.2002.00570_9.x. ISSN 0926-9959.
• Rubegni, P.; De Aloe, G.; Pianigiani, E.; Cherubini-Di Simplicio, F.; Fimiani, M. (2001). "Two sporadic cases of idiopathic multiple minute digitate hyperkeratosis". Clinical and Experimental Dermatology. 26 (1). Oxford University Press (OUP): 53–55. doi:10.1046/j.1365-2230.2001.00762.x. ISSN 0307-6938.