Hereditary progressive mucinous histiocytosis: first report in a male patient.

Progressive mucinous histiocytosis is a very rare, benign, non-Langerhans' cell histiocytosis limited to the skin. In total ten patients (all women) in four families and three sporadic cases have been reported. We report here the first published case of a male patient with progressive mucinous histiocytosis. The multiple red papules on the scalp and forearms were asymptomatic and had slowly increased over approximately the past 20 years. The patient's mother had similar lesions. Histological examination revealed nodules in the dermis with histiocytes and mucin deposition. The histiocytes stained positively with CD31 and negative with CD34, CAM 5.2, PGM-1 and factor XIIIa. Ultrastructurally, the histiocytes showed numerous circular myelin bodies and zebra bodies reminiscent of those seen in lysosomal storage diseases. The genetic transmission of hereditary progressive mucinous histiocytosis remains unclear; we assume an autosomal dominant transmission with some hormonal factor that makes hereditary progressive mucinous histiocytosis more likely in women.

Cutaneous mucinosis in shar-pei dogs is due to hyaluronic acid deposition and is associated with high levels of hyaluronic acid in serum.

Cutaneous mucinosis affects primarily shar-pei dogs. Hyaluronic acid (HA) is considered to be the main component of mucin and CD44 is the major cell surface receptor of HA, necessary for its uptake and catabolism. The aims of this study were to identify the composition of the mucin in cutaneous mucinosis of shar-pei dogs, investigate the correlation between the deposition of HA and the expression of CD44, and determine whether shar-pei dogs with cutaneous mucinosis presented with elevated levels of serum HA. In skin biopsies, the mucinous material was stained intensely with Alcian blue and bound strongly by the hyaluronan-binding protein. No correlation was found between the degree of HA deposition in the dermis and the expression of CD44 in the skin of shar-pei dogs affected or unaffected by cutaneous mucinosis. A clear positive correlation was found between the existence of clinical mucinosis and the serum HA concentration. In control dogs, serum HA ranged from 155.53 to 301.62 microg L(-1) in shar-pei dogs; without mucinosis it ranged from 106.72 to 1251.76 microg L(-1) and in shar-pei dogs with severe mucinosis it ranged between 843.51 to 2330.03 microg L(-1). Altogether, the results reported here suggest that mucinosis of shar-pei dogs is probably the consequence of a genetic defect in the metabolism of HA.

Reticular erythematous mucinosis occurring in a brother and sister.

Reticular erythematous mucinosis (REM) is a rare, primary cutaneous mucinosis clinically characterized by a persistent reticular erythema on the mid chest and mid-upper back, and histologically by a mononuclear cell infiltrate and deposits of mucin in the dermis. To our knowledge, the present report of REM occurring in a Caucasian man and his sister is the first reported case of familial REM. Since a host-specific immune response to unknown antigens may be involved in the pathogenesis of this entity, human leukocyte antigen typing was determined and compared to those reported in autoimmune diseases.

Familial occurrence of axillary papular mucinosis.

Primary cutaneous mucinosis encompasses a wide range of different skin conditions with circumscribed, follicular or diffuse manifestation. For the first time, to our knowledge, we report on the occurrence of so-called "atypical" localized papular mucinosis in the axillary pits of a mother and her (identical) twin daughters presenting as asymptomatic soft minuscule papules. This unique observation allows us to define an autosomal dominant inheritance pattern with a high level of penetrance for this rare skin disease.

Cutaneous mucinosis of infancy: is it a real entity or the paediatric form of lichen myxoedematosus (papular mucinosis)?

We describe a girl presenting with a childhood dermal mucinosis in which we had the unique opportunity to find all the transitional histological features of lichen myxoedematosus (papular mucinosis), from its early focal mucin deposition in the reticular dermis to its late findings of interstitial mucin deposition, dermal fibrosis and fibroblast proliferation. Her father reported having had similar lesions when he was a child, which completely disappeared during adolescence. This case, and a re-evaluation of the literature, suggests that cases of cutaneous mucinosis of infancy that are not hamartomatous conditions such as mucinous naevi are in fact the infantile presentation of lichen myxoedematosus (papular mucinosis) and, in addition to other cases in the literature, suggests a genetic and familial factor in lichen myxoedematosus (papular mucinosis).

Hereditary progressive mucinous histiocytosis.

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.

Self-healing infantile familial cutaneous mucinosis.

Childhood cutaneous mucinoses have been rarely reported and are difficult to classify. We describe two brothers who developed multiple, extensive cutaneous lesions during the first few months of life. Histologically the lesions were composed of mucin deposits in the dermis. In the first patient, the lesions spontaneously disappeared over the years. We believe that familial self-healing cutaneous mucinosis represents a unique entity not previously reported.

Hereditary progressive mucinous histiocytosis. Immunohistochemical and ultrastructural studies in an additional family.

BACKGROUND: Hereditary progressive mucinous histiocytosis was first described in 1988. The clinical features of this probably autosomal dominant inherited disease are skin-colored or red pea-sized tumors all over the skin appearing in the first decades of life and increasing gradually in number throughout life. In contrast to other benign histiocytic skin diseases there is no spontaneous tumor resolution. OBSERVATION AND RESULTS: A 52-year-old woman and her 25-year-old daughter of a further family are reported. Both showed similar longstanding lesions without tumor regression. There was no evidence of visceral involvement. Histologic, immunohistochemical, and ultrastructural examinations revealed histiocytes from the monocyte/macrophage subset as the main constituents of the tumors. The cells contained abundant zebra and myeloid bodies and vacuoles indicating a lysosomal storage disease. Special investigations, however, such as lymphocytic storage, thin-layer chromatography of the involved tissue, lysosomal enzymes in serum, and enzymes released from cultured fibroblasts showed negative results. A pathologic accumulation of mucopolysaccharides or phospholipids in serum or urine or a basic enzyme defect could not be detected. CONCLUSIONS: Hereditary progressive mucinous histiocytosis has been previously reported in seven patients, all of whom were female. A pathologic proliferation of histiocytic cells from the monocyte/macrophage subset with lysosomal storage phenomena gives rise to the clinical symptoms. The disease does not correspond to one of the known lysosomal storage diseases. Since exact information on the stored material is still lacking, it cannot be ruled out that the disease is not primarily a true storage disease but a proliferation and accumulation of macrophages due to a hitherto unknown and persistent stimulus.