Hereditary progressive mucinous histiocytosis

Abstract

We describe a 61-year-old woman who presented with multiple small, firm, shiny, skin-coloured papules in a symmetrical pattern on the dorsum of the hands, sides of the fingers and extensor aspect of the forearms. These had slowly increased in number over a period of 40 years, and were asymptomatic. Both laboratory results and systemic review were unremarkable. Histological examination of six papules revealed well-circumscribed but unencapsulated dermal nodules composed of epithelioid histiocytes and abundant alcian blue-positive mucin separating broad bundles of collagen. Histiocytes within the nodule stained positively with vimentin, and were focally positive for alpha1-antitrypsin and lysozyme. The interstitium was positive for tenascin. On electron microscopy, the histiocytes showed numerous circular, osmophilic myelin bodies and zebra bodies reminiscent of those seen in lysosomal storage diseases. Our patient's clinical, histological and ultrastructural features have been previously described as hereditary progressive mucinous histiocytosis, a rare familial form of eruptive histiocytoma characterized by multiple persistent papules with prominent mucinosis.

Two sporadic cases of adult‐onset progressive mucinous histiocytosis

“…No association with paraproteinaemia has been observed. Ten cases – all women – in four families and one sporadic case have been described in the literature 1–6 . An autosomal dominant pattern of inheritance has been suggested.…”

“…Progressive mucinous histiocytosis is a rare, benign, non‐Langerhans' cell histiocytosis limited to the skin. Ten cases – all women – in four families and one sporadic case have been described in the literature 1–6 . The disorder, characterized by few to numerous flesh‐coloured to red‐brown asymptomatic papules on the face, the hands, the arms and the legs, usually begins in childhood 1–6 .…”

Unusual variants of non-Langerhans cell histiocytoses

“…The disease is very rare and affects almost exclusively women; only 11 patients from 6 different families, [46][47][48][49][50][51] in addition to two sporadic cases, 52,53 have been reported. Indeed, we observed a male patient and his daughter both affected by HPMH (unpublished data).…”

“…Typical pleomorphic granules, as described by one of us, 33 wormlike bodies, or Birbeck granules are absent. [46][47][48][49][50][51][52][53] Course and prognosis…”

Progressive Mucinous Histiocytosis: Importance of Electron Microscopy to Confirm Diagnosis

“…1 HPMH is a benign, non-Langerhans cell histiocytosis that was first described in 1988 by Bork and Hoede. 2,3 HPMH is characterized by few to numerous skin-colored to red-brown pea-sized papules, with a predilection to localize on the face, hands, forearms, and legs.…”