Self-healing juvenile cutaneous mucinosis

Self-healing juvenile cutaneous mucinosis, a sclerodermoid disorder simulating juvenile dermatomyositis: a case-based review

Self-healing juvenile cutaneous mucinosis (SHJCM) is a rare childhood disease with characteristic cutaneous and rheumatic manifestations. Cutaneous manifestations include a combination of nodules affecting peri-articular (especially interphalangeal joints) and head and neck areas; and linearly arranged ivory white papules over an erythematous indurated skin. Despite a benign course, an abrupt onset of symptoms with extensive cutaneous involvement often leads to parental anxiety, overenthusiastic evaluation and sometimes aggressive treatment. A peculiar cutaneous distribution in SHJCM including nodular lesions and periorbital edema, arthritis and arthralgia in a few cases, may simulate juvenile dermatomyositis. It is, therefore, important for dermatologists and pediatricians to be aware of this entity. In this report, we describe two cases of SHJCM and briefly review similarly reported cases in children.

Nodular lesions of self-healing juvenile cutaneous mucinosis: a pitfall!

Self-healing juvenile cutaneous mucinosis (SHJCM) is a rare disorder of unknown origin, which occurs in children in good health. It is characterized by the multiplication of transient cutaneous papules and nodules, mainly located on the head and periarticular areas that spontaneously resolve. Histological features of SHJCM have been well described; therefore, the diagnosis is usually made easily when papules are biopsied. We report a series of 3 new cases of SHJCM presenting mainly with nodular lesions. Histological examination of these nodules showed either lesions consistent with nodular or proliferative fasciitis or nonspecific panniculitis. Mucinous deposits were present but often inconspicuous, so could be disregarded. We wanted to emphasize this misleading presentation because a biopsy for histological examination is always mandatory in cases of proliferating nodules to rule out malignant tumors. Therefore, the diagnosis always requires discussion between pathologists and clinicians to rapidly reassure the parents and avoid inappropriate therapy.

Self-healing juvenile cutaneous mucinosis: Cases highlighting subcutaneous/fascial involvement

BACKGROUND

Self-healing juvenile cutaneous mucinosis is a rare disease affecting young people characterized by transient cutaneous lesions and sometimes mild inflammatory symptoms. The deep dermal and subcutaneous features of this disorder have not yet been well described.

OBJECTIVE

The purpose of our study was to present 3 cases of self-healing juvenile cutaneous mucinosis in which the histopathologic features caused diagnostic confusion between this disorder and proliferative fasciitis.

METHODS

The study includes clinical and histologic findings of 3 patients, complemented by a literature review.

RESULTS

The histologic descriptions of nodular lesions in self-healing juvenile cutaneous mucinosis reveal features of proliferative fasciitis, including a myxoid stroma and gangliocyte-like giant cells.

LIMITATIONS

Self-healing juvenile cutaneous mucinosis is a rare condition and has not been frequently reported in medical literature. Our findings are based on the pathologic features of 3 patients.

CONCLUSIONS

Our findings further elucidate the histologic features of self-healing juvenile cutaneous mucinosis and expand the differential diagnosis for entities in which gangliocyte-like giant cells are noted.

Adult variant of self-healing papular mucinosis in a patient with rheumatoid arthritis: predominant proliferation of dermal dendritic cells expressing CD34 or factor XIIIa in association with dermal deposition of mucin

According to a recent classification, self-healing papular mucinosis (SHPM) is a subtype of papular mucinosis (also known as lichen myxedematosus), which is in turn a type of idiopathic localized cutaneous mucinosis. SHPM tends to occur in children, but there have been a few reports of an adult type. We report a 70-year-old Japanese woman who presented with reddish, rice-kernel-sized papules of a few days' duration on her right arm. She had a 25-year history of rheumatoid arthritis, which had been well treated with a low dose of corticosteroid as well as some other medications. No paraproteinemia or thyroid dysfunction were observed. The eruptions spontaneously resolved within 2.5 months of onset. Histological findings showed a well-circumscribed mucinous stroma surrounded by dermal mesenchymal cells, such as fibroblast-like cells in the middle of the dermis. Immunohistochemically, these cells were positive only for vimentin on the mucinous lesion. On the circumference of the mucinous lesion, these cells expressed either CD34 or factor XIIIa (FXIIIa). Because vimentin was common to dermal mesenchymal cells, we defined the cells expressing CD34 or FXIIIa, except for vimentin+ cells lacking CD34 or FXIIIa, as dermal dendritic cells (DDC). The findings of the present case suggest that CD34+ or FXIIIa+ DDC and tryptase-positive mast cells on the perilesional area in combination with vimentin+ cells on the mucinous lesion might have given rise to the dermal deposition of mucin in our case. These cells, which are possibly activated in an autoimmune manner associated with rheumatoid arthritis, might play important roles in the development of dermal deposition of mucin in SHPM.

Self-healing juvenile cutaneous mucinosis

Self-healing juvenile cutaneous mucinosis is an extremely uncommon disorder characterized by the acute eruption of multiple papules and subcutaneous nodules. In this report, we describe one of the youngest patients reported to date with self-healing juvenile cutaneous mucinosis and further define several of the histologic and clinical characteristics unique to the disorder. Awareness of this disease is important because, despite an ominous presentation, all reported cases have resolved spontaneously. Therefore, aggressive therapy should be avoided.

Self-healing juvenile cutaneous mucinosis

A healthy 14-month-old black girl presented with a 3-week complaint of "knots" on the face and hands. The lesions were acute in onset and asymptomatic. Multiple, firm, nontender, skin-colored to erythematous nodules were noted on the scalp, forehead, axillae, lower legs, abdomen, and hands. A skin biopsy specimen revealed a well-circumscribed accumulation of mucin in the reticular dermis. Colloidal iron stain was positive. Radiographs showed soft tissue prominence only. Serum protein electrophoresis, thyroid function tests, complete blood count, sedimentation rate, and antinuclear antibody were normal, except for lymphocytosis. Findings were consistent with self-healing juvenile cutaneous mucinosis (SHJCM). SHJCM is a condition of unknown etiology characterized by rapid onset of asymptomatic, indurated papules or nodules. Affected children may have arthralgias, but are otherwise well. Spontaneous resolution is the rule. Most skin lesions in our patient had resolved within 6 months of onset. This patient is unique because of the young age of onset.