Two sporadic cases of adult-onset progressive mucinous histiocytosis.

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. The disorder usually begins in childhood and progresses slowly. We report two sporadic cases of adult-onset progressive mucinous histiocytosis in unrelated African-American women, aged 48 and 55 years, respectively, who developed red-brown and flesh-coloured, asymptomatic papules on the face, the arms and the legs without truncal, mucosal or visceral involvement. The lesions showed no spontaneous regression. Both patients lacked associated systemic symptoms, including polyuria, polydipsia or seizures. There was no underlying hyperlipidaemia, paraproteinaemia or lymphoproliferative disease. No family history of similar lesions could be identified. Light microscopy revealed dermal proliferation of spindle-shaped histiocytes with abundant mucin deposition. Electron microscopy demonstrated a high number of myelin figures or zebra bodies in the cytoplasm of histiocytes. On immunohistochemistry, positive staining with macrophage markers--CD68, HAM56 and lysozyme--and factor XIIIa, a transglutaminase present in dermal dendrocytes, and negative staining with Langerhans' cell markers--CD1a and S100--and CD34, a marker present in dermal dendritic cells derived from uncommitted mesenchymal cells, were observed.

Coccidioidomycosis--the airborne assault continues: an unusual presentation with a review of the history, epidemiology, and military relevance.

Despite remarkable advances in detection and therapy, coccidioidomycosis remains a persistent threat to military troops deployed in endemic areas. Pregnant women, immunocompromised hosts, and dark-skinned persons, particularly those of Filipino, African, Hispanic or Asian ancestry, are at greatest risk for disseminated coccidioidomycosis. The ethnically diverse military forces have susceptible active duty and reserve members stationed at or temporarily trained on bases located in endemic areas for Coccidioides immitis. Although the vast majority of infections with this organism are subclinical, unusual patterns of dissemination pose a diagnostic challenge. The military physician may be tasked with recognizing acute non-specific symptoms as well as bizarre, occult manifestations of coccidioidomycosis. We present a case of disseminated coccidioidomycosis in an active duty Caucasian male who presented with a right shoulder mass. Our patient is atypical in that he had disseminated disease although immunocompetent and Caucasian. Another unusual feature is that the mass was not preceded or accompanied by any other symptoms. We could find only two other reported cases of coccidioidomycosis presenting as a soft tissue mass, both in African-American patients. The epidemiology and history of coccidioidomycosis will be reviewed, with an emphasis on military populations. The insidious nature of coccidioidomycosis, the importance of early detection and treatment in decreasing morbidity and mortality, and the presence of large numbers of military members in the endemic areas make the lessons of this case particularly relevant for all flight surgeons.

Collecting duct meningeal carcinomatosis.

Collecting duct carcinoma (CDC) is an aggressive primary renal neoplasm that represents a distinct subtype of renal cell carcinoma. Histochemical (eg, mucicarmine) and immunohistochemical (eg, Ulex europaeus) studies, taken in concert with the gross and histologic findings, allow differentiation of CDC from the conventional varieties of renal cell carcinoma in most cases. Collecting duct carcinoma generally pursues a more aggressive course than conventional renal cell carcinoma. Metastases to regional lymph nodes, bone, adrenal glands, lung, and skin have been reported in CDC. We describe the case of a 26-year-old man who presented with a clinical and radiologic impression of multifocal meningioma. Biopsies of the meninges and extracranial soft tissues revealed metastatic adenocarcinoma; subsequent studies suggested metastatic CDC. Ultrasound-guided biopsy was performed on a subsequently identified renal mass, which showed features consistent with CDC. To our knowledge, this is the first reported case of meningeal carcinomatosis due to CDC. The diagnostic features of this tumor are discussed.