The biopsy specimen revealed hyperkeratosis with aggregates of eosinophil amorphous material in the upper half of the stratum corneum. The malpighian stratum and dermis were normal. A Prussian blue stain was negative for iron.
Both the clinical and the histopathologic features were compatible with a diagnosis of palmar petechiae, or black palm. Black palm is the palmar equivalent of the more common black heel, or talon noir .1,2 Other suggested names for this disorder include tache noir and posttraumatic punctate hemorrhage . A literature search revealed only 4 similar case reports. In 2 of the reports, the lesions appeared suddenly a few days after a traumatic event, namely weightlifting3 and a self-inflicted hammer blow.4 There is no description of the preceding event in the 2 cases of Nabai and Mehregan.5
Black Palmar Macules. Arch Dermatol. 1998;134(8):1019-1024. doi: