Isolated Non-Resolving Vulvar Lesion as a Presentation of Disseminated Histoplasmosis in a Woman with HIV

Disseminated histoplasmosis is most commonly caused by Histoplasma capsulatum and is a known opportunistic infection in immunocompromised patients. The clinical presentation of histoplasmosis varies from asymptomatic to a progressive disseminated form. Pulmonary and CNS involvement is common in disseminated histoplasmosis. Rarely, disseminated disease can present as vulvar lesion in the absence of pulmonary symptoms, causing a delay in diagnosis. As per our PubMed literature search, there have only been two reported cases where vulvar lesion was the only presenting symptom of disseminated disease. In our patient, a histopathological diagnosis was made with staining showing budding yeast forms of histoplasma.

LEARNING POINTS

Histoplasmosis can be a cause of isolated non-resolving vulvar lesion in immunocompromised patients.In patients at risk, we recommend work-up for disseminated histoplasmosis with urine histoplasma antigen and further imaging to rule out disseminated infection when histoplasma is identified on local biopsy samples.In patients from endemic regions and in non-resolving vulvar lesions, fungal infection should be considered.

Blood markers for vasculogenesis increase with tumor progression in patients with breast carcinoma

Recent studies show that AC133-a hematopoietic stem cell antigen, when coex-pressed with endothelial markers, identifies a population of endothelial precursor cells (EPCs) in peripheral blood that function in tumor vasculogenesis in animals. Little is known about whether EPCs contribute to human tumor vasculogenesis. We attempted to determine if, through increased peripheral expression of AC133 or endothelial markers previously associated with EPCs,VEGFR-2 and Tie-2, we could detect an EPC response in the blood of patients with breast carcinoma. Thirty patients were segregated based on their breast biopsy histology into infiltrating carcinoma, DCIS and control groups. Using Real Time PCR, we measured the expression of the aforementioned markers in reverse transcribed RNA extracts from preoperative peripheral blood specimens. The cancer patients had significantly elevated Tie-2 expression with the highest levels associated with infiltrating carcinoma. Our data suggest increased circulating EPC markers in tumor patients, but further study of this cell population is needed to better define its role in tumor vasculogenesis.