Background: Multinucleated Cell Angiohistiocytoma (MCAH) is a rare disease, first described by Smith and Wilson Jones in 1985. Since then, less than 100 cases have been reported in the literature. Clinically it is characterized by papules or plaques arising from a specific anatomical area such as lower extremities, dorsum of the hands and face. Some generalized cases have been reported.
Main observations:We report a case of 77-year-old woman who presented with multiple itching. reddish to violaceous, flat to domed-shaped plaques on the lower legs with symmetrical and bilateral distribution along the saphena veins. On dermoscopy examination only a red-violaceous homogeneous area was visible. Histology showed remarkable proliferation of dilated small vessels in the upper and mid dermis and bizarre-shaped multinucleate giant cells with scalloped cytoplasm that were intermingled with numerous mononucleated spindle cells. Many mast cells containing the characteristic granules were also detected, often adjacent to the multinucleate cells. Based on the clinico-pathologic findings the diagnosis of MCAH was established.
Conclusions:To our knowledge, this is the first documented case of MCAH with a bilateral and linear pattern disposed on the lower limbs, following the saphena veins. In this patient chronic trauma induced by ambulation might have contributed to development of the lesions. (J Dermatol Case Rep. 2016; 10(4) MCAH is more frequent in elderly women than in men, suggesting that hormones can have a role in the pathogenesis of this entity. The typical clinical features consist of a cluster of red to violaceous papules or plaques, ranging in size from few millimetres to 1.5 cm, located on a single anatomical area as lower extremities, dorsum of the hands, wrists, fingers or face. The lesions can be arranged in an annular configuration or grouped in a cluster and are usually asymptomatic but may be rarely itchy. The clinical differential diagnoses may include dermatofibroma, angiofibroma, Kaposi sarcoma, pseudo-Kaposi sarcoma, granuloma anulare, lichen planus, pyogenic granuloma, giant-cell fibroblastoma, sarcoidosis and insect bite.
Case ReportWe report a 77-year-old woman who presented with a 5-year history of multiple papules on the lower extremities. The patient reported that the first lesion appeared after a holiday and it was initially diagnosed as a mosquito bite. With time the lesion did not regress and new similar lesions occurred at the same site. Treatment with argon laser, performed by another institution, was unsuccessful. Physical examination showed multiple itching reddish to violaceous, flat to domed-shaped plaques on the lower legs with an unusual DOI: http://dx.doi.org/10.3315/jdcr.2016.1237 58 symmetrical and bilateral distribution along the saphena veins (Fig. 1). The overall lesions count was 38 and the size varied from 6 to 13 mm. Clinical diagnoses included Kaposi sarcoma, dermatofibroma and angiofibroma.On dermoscopy examination we observed no specific clues for the diagnosis. Only a...
