Update on the spectrum of histoplasmosis among hispanic patients presenting to a New York City municipal hospital: A contemporary case series

Disseminated Histoplasmosis with Underlying Sarcoidosis-Rheumatoid Arthritis Overlap Syndrome: An Example of Diagnostic Test Threshold of Detection Affecting Test Results and Patient Care

Histoplasmosis is common in many parts of the world but with areas of hyperendemicity. Disseminated histoplasmosis is the deadliest form of histoplasmosis and is most common among immunocompromised patients. Timely diagnosis is crucial to improve outcomes. We describe a patient on azathioprine and rituximab with disseminated histoplasmosis in which diagnosis was delayed in part because of negative early Histoplasma antigen testing, which was positive later in the course. This case serves as an example of the concept of “threshold of detection” in which a certain concentration of a microbe must be present for it to be detected by a diagnostic test that focuses on detection of a microbe or its components. This concept applies to many tests used to diagnose infectious diseases.

Close encounters of three kinds: Case-based report of endemic mycoses in the environs of New York city

The term "endemic mycoses" refers to a group of fungi that maintains a baseline rate of infection only in certain geographical regions due to the hospitable enviormental conditions these regions offer. In the United States, Histoplasma capsulatum, Coccidioides spp, and Blastomyces dermatitidis are the three most prevalent endemic human fungal infections. The traditional endemic regions for these pathogens are defined based on data acquired many decades ago, and case detection is subject to diagnostic delays even in classically endemic areas, a problem that is likely to be magnified in areas less familiar with these fungal infections. The present series includes an example of each of these infections diagnosed in a medical center situated in the suburbs of New York City, a location not considered endemic for any of them. Likely routes of acquisition for the three patients are considered, and the history of encounters with these pathogens in New York State is briefly recounted. Altogether, this report is intended to serve as a reminder to clinicians that traditional distribution maps for the endemic mycoses are bound to be outdated in the face of modern trends in globalization, population dynamics, and ecological change.