Clinical, biochemical, and epidemiological characteristics of patients infected with Histoplasma capsulatum in a non-endemic area of Mexico

Abstract

Introduction: Histoplasmosis is the most prevalent systemic mycosis in Mexico. However, since 1995, the routine registry of this disease was interrupted in the country; therefore, the current magnitude of the disease is unknown. This study aimedto describe the epidemiological, clinical, and paraclinical characteristics of the histoplasmosis infectionwhich has a wide variety of clinical manifestations -in the population that received care in Mexico's National Institute for Respiratory Diseases. Material and methods:This study used a retrospective design, and the analyzed data were collected from January 2013 to December 2016.We conducted a comparison of characteristics between patients with pulmonary or disseminated forms of histoplasmosis through χ2, Student's T, or Mann-Whitney U tests.Results: In total, 61 patients were included. The average age was 36.1 years ± 12.4; 53 (87%) were men, and the male-female ratio was 6:1. Moreover, 80% of the patients had immunosuppression; 94% had HIV; 50.8% had disseminated histoplasmosis, so it had the most common presentation;and 57% had anemia (i.e. median Hb 10 g/dL). Of the 118 fungus cultures, 74% (87) reported growth. The Histoplasma antigen was positive in 67% (14/21) of the cases, andmortality rate was estimated at 7%. Conclusions:Compared with data published in 1995, we observed a change in the epidemiology and risk factors of histoplasmosis; specifically, there was a lower proportion of occupational exposure and an increase in the number of cases in non-endemic areas (i.e. low risk of transmission). Our results generally corroborate the literature, suggesting that the acquired immunodeficiency syndrome (AIDS) pandemic, the use of immunosuppressant therapy, and the rise in the number of transplants have increased the overall risk of histoplasmosis, even in areas that were not previously identified as endemic. Generally, our studyhighlights the importance of routine registry of this disease in Mexico.

Disseminated Histoplasmosis Found in Bone Marrow in a Newly Diagnosed AIDS Patient: A Literature Review and Report of a Rare Case

“…Histoplasmosis is noted to be the most common endemic mycosis in the United States [ 2 ], but it is also noted to be the most prevalent systemic mycosis in Mexico [ 4 ]. Histoplasma is considered to be endemic in Mexico with cases found in 23 of the 32 states, and a higher number of reported cases are found in the states of Morelos, Guerrero, and Veracruz [ 4 ].…”

“…Histoplasmosis is noted to be the most common endemic mycosis in the United States [ 2 ], but it is also noted to be the most prevalent systemic mycosis in Mexico [ 4 ]. Histoplasma is considered to be endemic in Mexico with cases found in 23 of the 32 states, and a higher number of reported cases are found in the states of Morelos, Guerrero, and Veracruz [ 4 ]. However, cases of Histoplasmosis are being identified in previously low endemicity areas in Mexico, which suggests more current information needs to be obtained regarding the geographic distribution of Histoplasma.…”

“…However, cases of Histoplasmosis are being identified in previously low endemicity areas in Mexico, which suggests more current information needs to be obtained regarding the geographic distribution of Histoplasma. The endemicity of Histoplasma is significant as a risk factor for developing a disseminated infection, as the population living in higher endemic areas has an increased rate of exposure, reportedly between 60% and 90% [ 4 ].…”

“…In terms of radiographic findings, calcified lung nodules, consolidation, and hilar lymphadenopathy may be seen in people living in endemic areas. The disseminated form of histoplasmosis can present with lung nodules in a miliary distribution [ 4 ]. Regarding laboratory abnormalities, lactate dehydrogenase (LDH) elevation, aspartate aminotransferase (AST), or alanine transaminase (ALT) alterations, decreased platelet, hemoglobin, or leukocyte counts are commonly encountered [ 4 ].…”

“…The disseminated form of histoplasmosis can present with lung nodules in a miliary distribution [ 4 ]. Regarding laboratory abnormalities, lactate dehydrogenase (LDH) elevation, aspartate aminotransferase (AST), or alanine transaminase (ALT) alterations, decreased platelet, hemoglobin, or leukocyte counts are commonly encountered [ 4 ]. Although there are various clinically supportive data, isolation of Histoplasma in cultures provides definitive evidence for the infection, and a higher percentage of culture-positive cases can be found in disseminated histoplasmosis [ 4 ].…”