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"Colombo, Arnaldo L"
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Epidemiology of Candidemia in Latin America: A Laboratory-Based Survey
2013
The epidemiology of candidemia varies depending on the geographic region. Little is known about the epidemiology of candidemia in Latin America.
We conducted a 24-month laboratory-based survey of candidemia in 20 centers of seven Latin American countries. Incidence rates were calculated and the epidemiology of candidemia was characterized.
Among 672 episodes of candidemia, 297 (44.2%) occurred in children (23.7% younger than 1 year), 36.2% in adults between 19 and 60 years old and 19.6% in elderly patients. The overall incidence was 1.18 cases per 1,000 admissions, and varied across countries, with the highest incidence in Colombia and the lowest in Chile. Candida albicans (37.6%), C. parapsilosis (26.5%) and C. tropicalis (17.6%) were the leading agents, with great variability in species distribution in the different countries. Most isolates were highly susceptible to fluconazole, voriconazole, amphotericin B and anidulafungin. Fluconazole was the most frequent agent used as primary treatment (65.8%), and the overall 30-day survival was 59.3%.
This first large epidemiologic study of candidemia in Latin America showed a high incidence of candidemia, high percentage of children, typical species distribution, with C. albicans, C. parapsilosis and C. tropicalis accounting for the majority of episodes, and low resistance rates.
Journal Article
Epidemiology of Opportunistic Fungal Infections in Latin America
by
Tobón, Angela M.
,
Restrepo, Angela
,
Colombo, Arnaldo L.
in
AIDS
,
Antifungals
,
Biological and medical sciences
2010
This review discusses the epidemiology of the most clinically relevant opportunistic fungal infections in Latin America, including candidiasis, cryptococcosis, trichosporonosis, aspergillosis, and fusariosis. The epidemiologic features, including incidence, of some of these mycoses are markedly different in Latin America than they are in other parts of the world. The most consistent epidemiologic data are available for candidemia, with a large prospective study in Brazil reporting an incidence that is 3- to 15-fold higher than that reported in studies from North America and Europe. Species distribution also differs: in Latin America, the most common Candida species (other than Candida albicans) causing bloodstream infections are Candida parapsilosis or Candida tropicalis, rather than Candida glabrata.
Journal Article
Detection of Multiple Nosocomial Trichosporon asahii Transmission Events via Microsatellite Typing Assay, South America
by
Dieleman, Chendo
,
Colombo, Arnaldo L.
,
Francisco, Elaine C.
in
Antifungal agents
,
Basidiomycota
,
Biological diversity
2025
The fungus Trichosporon asahii has emerged as a cause of nosocomial infections, particularly in immunocompromised patients. Given its rising prevalence, information on its genetic diversity and transmission dynamics is urgently needed. We developed a microsatellite typing tool to investigate the genetic relatedness of T. asahii isolates. We selected 6 microsatellite markers from nanopore long-read sequencing of the T. asahii type-strain CBS 2479. We applied those markers to 111 clinical and environmental isolates; microsatellite typing showed high variability among isolates (11-37 alleles per marker) and identified 71 genotypes with strong discriminatory power (Simpson index of 0.9793). We applied the microsatellite typing method to T. asahii isolates from South America and identified multiple nosocomial transmission events from hospitals in Brazil, including clusters spanning more than a decade. The panel we developed offers high reproducibility and specificity, making it an effective tool for tracking outbreaks and determining the public health effects of T. asahii infections.
Journal Article
Earlier Diagnosis of Invasive Fusariosis with Aspergillus Serum Galactomannan Testing
by
Colombo, Arnaldo L.
,
Garnica, Marcia
,
Nucci, Marcio
in
Antifungal Agents - therapeutic use
,
Antigens
,
Aspergillosis
2014
Cross-reactivity of Fusarium species with serum galactomannan antigen (GMI) test has been observed. We sought to evaluate if GMI could help to early diagnose invasive fusariosis and to monitor treatment response. We reviewed the records of all patients with invasive fusariosis between 2008 and 2012 in three Brazilian hospitals. We selected patients who had at least 1 GMI test within 2 days before or after the date of the first clinical manifestation of fusariosis, and analyzed the temporal relationship between the first positive GMI test and the date of the diagnosis of invasive fusariosis, and the kinetics of GMI in relation to patients' response to treatment. We also selected 18 controls to determine the sensitivity and specificity of the test. Among 18 patients, 15 (83%) had at least one positive GMI (median 4, range 1-15). The sensitivity and specificity of was 83% and 67%, respectively. GMI was positive before the diagnosis of invasive fusariosis in 11 of the 15 cases (73%), at a median of 10 days (range 3-39), and after the diagnosis in 4 cases. GMI became negative in 8 of the 15 patients; 3 of these 8 patients (37.5%) were alive 90 days after the diagnosis of fusariosis compared with 2 of 7 (29%) who did not normalize GMI (p = 1.0). GMI is frequently positive in invasive fusariosis, and becomes positive before diagnosis in most patients. These findings may have important implications for the choice of antifungal therapy in settings with high prevalence of invasive fusariosis.
Journal Article
Emergence of Candida auris in Brazil in a COVID-19 Intensive Care Unit
by
de Groot, Theun
,
Colombo, Arnaldo L.
,
Francisco, Elaine C.
in
Amphotericin B
,
Brazil
,
Brief Report
2021
In December 2020, Candida auris emerged in Brazil in the city of Salvador. The first two C. auris colonized patients were in the same COVID-19 intensive care unit. Antifungal susceptibility testing showed low minimal inhibitory concentrations of 1 µg/mL, 2 µg/mL, 0.03 µg/L, and 0.06 µg/mL for amphotericin B, fluconazole, voriconazole, and anidulafungin, respectively. Microsatellite typing revealed that the strains are clonal and belong to the South Asian clade C. auris. The travel restrictions during the COVID-19 pandemic and the absence of travel history among the colonized patients lead to the hypothesis that this species was introduced several months before the recognition of the first case and/or emerged locally in the coastline Salvador area.
Journal Article
Epidemiologic and Clinical Progression of Lobomycosis among Kaiabi Indians, Brazil, 1965–2019
by
Colombo, Arnaldo L.
,
de Mendonça, Sofia B.M.
,
Rodrigues, Douglas A.
in
Archives & records
,
Brazil - epidemiology
,
Data analysis
2020
Lobomycosis is a rare granulomatous skin disease with a high prevalence in the Amazon region. The Kaiabi Indians are an especially affected group. We studied the current epidemiologic and clinical progression of lobomycosis among the Kaiabi in Brazil, from initial case reports in 1965 through 2019. A total of 60 lobomycosis cases had been reported among the Kaiabi, and we identified 3 new cases in our review. Of 550 cases of lobomycosis ever reported worldwide, 11.5% were among the Kaiabi. We note a high incidence among female Kaiabi and a precocious onset of disease in this indigenous population. Male Kaiabi frequently are infected with the multicentric form and women more frequently exhibit the localized form. Ulcerated lesions are observed more often in the multicentric form. The prevalence among this indigenous group could be explained by genetic susceptibility and lifestyle, which exposes them to a particular agent in the habitats in which they live.
Journal Article
Donor-Derived Transmission of Cryptococcus gattii sensu lato in Kidney Transplant Recipients
by
Colombo, Arnaldo L.
,
Cristelli, Marina P.
,
Santos, Daniel W.C.L.
in
Antifungal therapy
,
Antithymocyte globulin
,
Biopsy
2020
We describe cases of donor-derived transmission of Cryptococcus deuterogattii in 2 kidney transplant recipients in Brazil and published information on other cases. Prompt reduction of immunosuppression and initiation of antifungal therapy was required to successfully control the fungal infections and preserve engraftment.
Journal Article
Genotyping Reveals High Clonal Diversity and Widespread Genotypes of Candida Causing Candidemia at Distant Geographical Areas
by
Muñoz, Patricia
,
Parisi, Gabriella
,
Cantón, Emilia
in
Candida
,
Candidemia
,
Cellular and Infection Microbiology
2020
The objectives of this study were to gain further insight on
genotype distribution and percentage of clustered isolates between hospitals and to identify potential clusters involving different hospitals and cities. We aim to genotype
spp. isolates causing candidemia in patients admitted to 16 hospitals in Spain, Italy, Denmark, and Brazil. Eight hundred and eighty-four isolates (
= 534;
= 282; and
= 68) were genotyped using species-specific microsatellite markers. CDC3, EF3, HIS3, CAI, CAIII, and CAVI were used for
, Ctrm1, Ctrm10, Ctrm12, Ctrm21, Ctrm24, and Ctrm28 for
, and CP1, CP4a, CP6, and B for
. Genotypes were classified as singletons (genotype only found once) or clusters (same genotype infecting two or more patients). Clusters were defined as intra-hospital (involving patients admitted to a single hospital), intra-ward (involving patients admitted to the same hospital ward) or widespread (involving patients admitted to different hospitals). The percentage of clusters and the proportion of patients involved in clusters among species, genotypic diversity and distribution of genetic diversity were assessed. Seven hundred and twenty-three genotypes were detected, 78 (11%) being clusters, most of which (57.7%;
= 45/78) were intra-hospital clusters including intra-ward ones (42.2%;
= 19/45). The proportion of clusters was not statistically different between species, but the percentage of patients in clusters varied among hospitals. A number of genotypes (7.2%; 52/723) were widespread (found at different hospitals), comprising 66.7% (52/78) of clusters, and involved patients at hospitals in the same city (
= 21) or in different cities (
= 31). Only one
cluster was a widespread genotype found in all four countries. Around 11% of
and
isolates causing candidemia are clusters that may result from patient-to-patient transmission, widespread genotypes commonly found in unrelated patients, or insufficient microsatellite typing genetic discrimination.
Journal Article
Extracellular Vesicles from Candida haemulonii var. vulnera Modulate Macrophage Oxidative Burst
by
Bitencourt, Tamires A.
,
Colombo, Arnaldo L.
,
Santos, Patrick W. S.
in
Antibodies
,
Antigens
,
Candida
2023
Members of the Candida haemulonii species complex are multidrug-resistant emergent yeast pathogens able to cause superficial and invasive infections in risk populations. Fungal extracellular vesicles (EVs) play a critical role in the pathogenicity and virulence of several species and may perform essential functions during infections, such as carrying virulence factors that behave in two-way communications with the host, affecting survival and fungal resistance. Our study aimed to describe EV production from Candida haemulonii var. vulnera and evaluate whether murine macrophage RAW 264.7 cells respond to their stimuli by generating an oxidative response after 24 h. For this purpose, reactive oxygen species detection assays demonstrated that high concentrations of yeast and EVs (1010 particles/mL) of Candida haemulonii did not change macrophage viability. However, the macrophages recognized these EVs and triggered an oxidative response through the classical NOX-2 pathway, increasing O2•− and H2O2 levels. However, this stress did not cause lipid peroxidation in the RAW 264.7 cells and neither lead to the activation of the COX-2–PGE2 pathway. Thus, our data suggest that low concentrations of C. haemulonii EVs are not recognized by the classical pathway of the oxidative burst generated by macrophages, which might be an advantage allowing the transport of virulence factors via EVs, not identified by the host immune system that could work as fine tube regulators during infections caused by C. haemulonii. In contrast, C. haemulonii var. vulnera and high EV concentrations activated microbicidal actions in macrophages. Therefore, we propose that EVs could participate in the virulence of the species and that these particles could be a source of antigens to be exploited as new therapeutic targets.
Journal Article
Paracoccidioidomycosis in Immunocompromised Patients: A Literature Review
by
Peçanha-Pietrobom, Paula
,
De Almeida Jr, João
,
Colombo, Arnaldo
in
Acquired immune deficiency syndrome
,
AIDS
,
cancer
2018
Paracoccidioidomycosis (PCM) is an endemic mycosis found in Latin America that causes systemic disease mostly in immunocompetent hosts. A small percentage of PCM occurs in immunocompromised patients where low clinical suspicion of the infection, late diagnosis, and uncertainties about its management are factors that negatively impact their outcomes. We conducted a literature review searching reports on PCM associated to HIV, cancer, maligned hemopathies, solid organ transplantation, and immunotherapies, in order to check for peculiarities in terms of natural history and challenges in the clinical management of PCM in this population. HIV patients with PCM usually had low T CD4+ cell counts, pulmonary and lymph nodes involvement, and a poorer prognosis (≈50% mortality). Most of the patients with PCM and cancer had carcinoma of the respiratory tract. Among maligned hemopathies, PCM was more often related to lymphoma. In general, PCM prognosis in patients with malignant diseases was related to the cancer stage. PCM in transplant recipients was mostly associated with the late phase of kidney transplantation, with a high mortality rate (44%). Despite being uncommon, reactivation of latent PCM may take place in the setting of immunocompromised patients exhibiting clinical particularities and it carries higher mortality rates than normal hosts.
Journal Article