Progressive Nodular Histiocytosis: Report of a Case and Review of the Literature

Abstract

Progressive nodular histiocytosis (PNH) is a rare condition characterized by progressive eruption of multiple yellowish-brown papules and nodules on the skin and mucous membranes. We present the case of a 37-year-old Caucasian man with gradually increased appearance of nodular lesions on the forehead and right temple. These lesions were initially diagnosed as xanthomas and did not respond to intralesional injections of triamcinolone. Additional biopsy revealed an intense dermal infiltrate of foamy mononuclear epithelioid cells with a minor admixture of plasma cells, lymphocytes, and scattered multinucleated giant cells. On immunohistochemical staining, the lesional cells were positive for CD163 and CD68 and negative for CD1a, thus confirming a mononuclear-macrophage lineage. The clinical presentation and the histological impression lead to the diagnosis of PNH. This condition could be challenging, mimicking microscopically similar lesions of the non-Langerhans cell histiocytosis group. Although uncommon, PNH stands out due to its clinical and microscopic features and should be taken into consideration in the differential diagnosis of cutaneous histiocytoses.

A Rare Case of Combined Langerhans Cell Histiocytosis and Adult-Onset Xanthogranuloma: A Case Report

“…Juvenile xanthogranuloma (JXG) is the most common form of non-Langerhans cell histiocytic disorder in childhood and rarely is found in adults as AXG, with a peak incidence in the late 20s to 30s [ 4 ]. The majority of adult patients have solitary lesions [ 5 ]. The true incidence, however, may be underestimated, as many lesions, especially those which are solitary and small (up to 90% of all patients), may go unrecognized.…”