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A myriad of reasons, or a combination of them, have been alluded to in order to explain the lower susceptibility of children to SARS-CoV-2 infection and the development of severe forms of COVID-19. This document explores an additional factor, still little addressed in the medical literature related to the matter: nonspecific resistance to SARS-CoV-2 that could be generated by vaccines administered during childhood. The analysis carried out allows one to conclude that a group of vaccines administered during childhood is associated with a lower incidence and severity of SARS-CoV-2 infection among pediatric ages. Looking from an epidemiological perspective, this conclusion must be taken into consideration in order to ensure greater rationality in the design and implementation of prevention and control actions, including the administration of the COVID-19 vaccine, for these ages.
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Spirometra (Cestoda: Diphyllobothriidea) affects humans and some species of domestic and wild animals which eventually interact with humans. In this article, we report three new cases of Spirometra decipiens (Diesing, 1850) infection observed in two intermediate hosts and one definitive host, in Cuba. Genetic and morphological identification of S. decipiens in two snakes and a domestic dog were carried out by molecular means and routine histological study using hematoxylin-eosin staining, respectively. Taken together, the anatomical location, the host species infected with the specimens and their morphological and genetic features, all the samples were identified as S. decipiens. In each of the three cases, PCR assays using specific primers amplified bands that corresponded to S. decipiens species. To our knowledge, this paper is the first report of S. decipiens in species of Cuban endemic fauna and in the Caribbean islands. These species constitute a real or potential risk of transmission of Spirometra to humans in Cuba.
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There is an increasing attention to the emerging health problem represented by the clinical and functional long-term consequences of SARS-CoV-2 infection, referred to as postacute COVID-19 syndrome. Clinical, radiographic, and autopsy findings have shown that a high rate of fibrosis and restriction of lung function are present in patients who have recovered from COVID-19. Patients with active TB, or those who have recovered from it, have fibrotic scarred lungs and, consequently, some degree of impaired respiratory function. Helminth infections trigger predominantly type 2 immune responses and the release of regulatory and fibrogenic cytokines, such as TGF-ß. Here, we analyze the possible consequences of the overlapping of pulmonary fibrosis secondary to COVID-19 and tuberculosis in the setting of sub-Saharan Africa, the region of the world with the highest prevalence of helminth infection.
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OBJECTIVES: To provide original data on Pneumocystis primary infection in non-immunosuppressed infants from Peru. METHODS: A cross sectional study was performed. Infants less than seven months old, without any underlying medical conditions attending the "well baby" outpatient clinic at one hospital in Lima, Peru were prospectively enrolled during a 15-month period from November 2016 to February 2018. All had a nasopharyngeal aspirate (NPA) for detection of P. jirovecii DNA using a PCR assay, regardless of respiratory symptoms. P. jirovecii DNA detection was considered to represent pulmonary colonization contemporaneous with Pneumocystis primary infection. Associations between infants' clinical and demographic characteristics and results of P. jirovecii DNA detection were analyzed. RESULTS: P. jirovecii DNA was detected in 45 of 146 infants (30.8%) and detection was not associated with concurrent respiratory symptoms in 40 of 45 infants. Infants with P. jirovecii had a lower mean age when compared to infants not colonized (p <0.05). The highest frequency of P. jirovecii was observed in 2-3-month-old infants (p < 0.01) and in the cooler winter and spring seasons (p <0.01). Multivariable analysis showed that infants living in a home with ≤ 1 bedroom were more likely to be colonized; Odds Ratio =3.03 (95%CI 1.31-7.00; p = 0.01). CONCLUSION: Pneumocystis primary infection in this single site in Lima, Peru, was most frequently observed in 2-3-month-old infants, in winter and spring seasons, and with higher detection rates being associated with household conditions favoring close inter-individual contacts and potential transmission of P. jirovecii.
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Pneumocystis carinii , Pneumocystis , Pneumonia por Pneumocystis , Estudos Transversais , Humanos , Lactente , Peru/epidemiologia , Pneumocystis carinii/genética , Pneumonia por Pneumocystis/diagnóstico , Pneumonia por Pneumocystis/epidemiologiaRESUMO
The results of the genotypic characterization of Pneumocystis jirovecii are described in lung tissue samples from 41 Cubans who died of AIDS with pneumocystosis between 1995 and 2008. Histological sections of the lung preserved as formalin-fixed and paraffin-embedded tissue were examined. PCR amplification and nucleotide sequencing of the two mitochondrial genes (large and small) of the pathogen allowed verification of a predominance of genotype 3 (85T/248C) of the large mitochondrial gene and genotype 3 (160A/196T) of the small mitochondrial gene over a period of 14 years (1995-2008). These results suggest that the 85T/248C//160A/196T genotype circulates with the highest frequency (81.3%) among AIDS patients in Cuba. Multilocus analysis indicates a limited circulation of pathogen genotypes on the island with the existence of a clonal genotype with an epidemic structure. Furthermore, it appears that circulating strains of P. jirovecii have not developed mutations related to sulfonamide resistance. Taken together, the data in this study revealed important elements about pneumocystosis in Cuban patients dying of AIDS and the usefulness of formalin-fixed and paraffin-embedded samples to carry out molecular epidemiology studies of P. jirovecii.
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Rhodococcus equi is an animal pathogen and zoonotic human opportunistic pathogen associated with immunosuppressive conditions. The pathogenicity of R. equi is linked to three animal host-associated virulence plasmids encoding a family of "Virulence Associated Proteins" (VAPs). Here, the PCR-based TRAVAP molecular typing system for the R. equi virulence plasmids was applied to 26 R. equi strains isolated between 2010 and 2016 at the Institute of Tropical Medicine "Pedro Kourí," Cuba, from individuals living with HIV/AIDS. TRAVAP detects 4 gene markers, traA common to the three virulence plasmids, and vapA, vapB, and vapN specific to each of the host-associated plasmid types (equine pVAPA, porcine pVAPB, and ruminant pVAPN). Of the 26 isolates, six were positive to the vapB (porcine-type) marker, 4 (15.4%) to the vapA (equine-type) marker, and 1 (3.8%) to the vapN (ruminant-type) marker. Most of the isolates 14 (53.8%) were negative to all TRAVAP markers, suggesting they lacked a virulence plasmid. To our knowledge, this work is the first to report the molecular characterization of R. equi isolates from Cuba. Our findings provide insight into the zoonotic origin of R. equi infections in people and the potential dispensability of the virulence plasmid in immunosuppressed patients.
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The exposure to airborne particulate matter (PM) and its constituents is an important factor to be considered when evaluating their potential health risk. Transition metals found in PM are known to contribute significantly to the exacerbation of respiratory ailments. Exposure to these constituents results in the induction of oxidative stress in the bronchial epithelium, thus promoting the secretion of inflammatory mediators. Therefore, it is important to know the contributions of PM2.5 constituents to further investigate their relationship with toxic responses and associated health risks. PM2.5 samples from three rural (Humacao, Guayama, and Guayanilla) and two urban (more populated) sites (Bayamón and Ponce) from Puerto Rico were analyzed for various inorganic constituents. A total of 59 trace elements were analyzed, of which eight were considered with the greatest toxic potential. The highest annual average concentration of PM2.5 was reported at the urban site of Ponce (5.82 ± 1.40 µg m-3), while Bayamón's average concentration was not as high (4.69 ± 1.30 µg m-3) compared to concentrations at the rural sites Humacao, Guayama, and Guayanilla (4.33 ± 1.20 µg m-3, 4.93 ± 1.50 µg m-3, and 4.88 ± 1.20 µg m-3 respectively. The concentration at the Ponce site exhibited the highest summer value (7.57 µg m-3) compared to that of all the rural sites (~ 6.40 µg m-3). The lowest summer PM2.5 values were obtained at the Humacao site with an average of 5.76 µg m-3. Average Cu and Zn concentrations were 3- and 2-fold higher at the urban sites (0.68 ng m-3 and 6.74 ng m-3 respectively) compared to the rural sites (0.17 ng m-3 and 4.11 ng m-3). Relative toxicity of inorganic PM extract indicates Bayamón (urban) and Guayama with similar low LC50 followed by Humacao, Guayanilla, and finally Ponce (urban) with the highest LC50. Of the eight potential toxic metals considered, only Fe was found to be higher at the rural sites. To our understanding, there are different sources of emission for these metals which potentially indicate main anthropogenic sources, together with the trade winds adding periodically volcanic and African Dust Storm particulates that affect Puerto Rico. These results are the first of their kind to be reported in Puerto Rico.
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Poluentes Atmosféricos , Material Particulado , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Porto Rico , Estações do AnoRESUMO
Sub-Saharan Africa is the region of the world with the highest prevalence of helminth infections. To protect themselves from the defensive mechanisms of their respective hosts, helminths modulate their immune responses. This modulation has relevant clinical and epidemiological consequences, including the inhibition of inflammatory processes that characterize infection by other microorganisms. Severe Pneumocystis pneumonia is characterized by an intense inflammatory reaction that can lead to death. Acquired immunodeficiency syndrome is the main predisposing factor to the development of pneumocystosis. Although the introduction of highly active antiretroviral therapy has led to a notable decline in the incidence of acquired immunodeficiency syndrome-associated complications, pneumocystosis continues to be an important global health problem. Despite the high incidence of human immunodeficiency virus infection in the sub-Saharan region, the prevalence of Pneumocystis pneumonia there has been lower than expected. Several factors, or combinations thereof, may contribute to this evolution. Here, we hypothesize the possible role of helminth immune modulation as an important issue at play. On the other hand, and looking ahead, we believe that the immune modulation achieved by helminths may be an important factor to consider during the design and evaluation processes of vaccines against Pneumocystis jirovecii to be used in Sub-Saharan Africa. The requirements of a balanced triggering of different types of immune responses for controlling the infection produced by this microorganism, as observed during experiments in animal models, support this final consideration.
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Pneumocystis pneumonia (PCP) remains the most frequent AIDS-defining illness in developed countries. This infection also occurs in non-AIDS immunosuppressed patients, e.g., those who have undergone an organ transplantation. Moreover, mild Pneumocystis jirovecii infections related to low pulmonary fungal burden, frequently designated as pulmonary colonization, occurs in patients with chronic pulmonary diseases, e.g., cystic fibrosis (CF). Indeed, this autosomal recessive disorder alters mucociliary clearance leading to bacterial and fungal colonization of the airways. This mini-review compiles and discusses available information on P. jirovecii and CF. It highlights significant differences in the prevalence of P. jirovecii pulmonary colonization in European and Brazilian CF patients. It also describes the microbiota associated with P. jirovecii in CF patients colonized by P. jirovecii. Furthermore, we have described P. jirovecii genomic diversity in colonized CF patients. In addition of pulmonary colonization, it appears that PCP can occur in CF patients specifically after lung transplantation, thus requiring preventive strategies. In other respects, Pneumocystis primary infection is a worldwide phenomenon occurring in non-immunosuppressed infants within their first months. The primary infection is mostly asymptomatic but it can also present as a benign self-limiting infection. It probably occurs in the same manner in CF infants. Nonetheless, two cases of severe Pneumocystis primary infection mimicking PCP in CF infants have been reported, the genetic disease appearing in these circumstances as a risk factor of PCP while the host-pathogen interaction in older children and adults with pulmonary colonization remains to be clarified.
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Fibrose Cística , Pneumocystis carinii , Pneumonia por Pneumocystis , Adulto , Brasil , Criança , Fibrose Cística/complicações , Humanos , Lactente , Pulmão , Pneumocystis carinii/genética , Pneumonia por Pneumocystis/complicaçõesRESUMO
Pneumocystis jirovecii and microsporidia species are recognized as opportunistic infectious pathogens in AIDS patients. Coinfection of both in one patient has been rarely reported. The aim of the present study was to investigate the coinfection of P. jirovecii and microsporidia in different tissues from AIDS deceased patients. Post mortem histological finding of P. jirovecii and microsporidia was demonstrated by means of the Grocott's methenamine silver and Brown Brenn staining, respectively. Molecular technique was used for identification and characterization of both fungi. Out of the 514 autopsied cases P. jirovecii and microsporidia species were identified in 53 (10.3%) and 62 (12.1%) cases respectively. A total of five cases (0.97%) coinfected with Pneumocystis and microsporidia were recovered from all analyzed autopsies. Coinfection of Pneumocystis and microsporidia is very challenging and raises interesting issues about host-parasite relationship. The early diagnosis of both pathogens must be crucial to establish correct and early treatments, improve the patient's evolution, reducing the risk of death.
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Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Coinfecção/microbiologia , Microsporídios/isolamento & purificação , Pneumocystis carinii/isolamento & purificação , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Adulto , Autopsia , Coinfecção/epidemiologia , Feminino , Humanos , Masculino , Microsporídios/genética , Pessoa de Meia-Idade , Pneumocystis carinii/genética , Adulto JovemRESUMO
BACKGROUND: Pneumocystisjirovecii primary infection occurs asymptomatically before 6 months of age, suggesting that the infection is acquired very early in life. Furthermore, Pneumocystis pneumonia has been described in newborns, which emphasizes the importance of studying Pneumocystis colonization in mother-infant pairs. AIMS: To evaluate the prevalence of Pneumocystis colonization among pregnant women and to determine the potential transplacental transmission. METHODS: A cross-sectional study was carried out on HIV-negative women over 18 years-old, and 37 or more weeks of pregnancy attending Hospital Cayetano Heredia Maternity unit during 2016-2017. Clinical and demographical information was collected on them and their newborns. Oropharyngeal washes, nasal swabs, and placenta samples were collected from women, as well as a nasopharyngeal aspirate and nasal swab from newborns. All respiratory samples were analysed by nested-PCR for the detection of Pneumocystis. Placenta samples from women with a positive PCR result in their respiratory samples were also analysed by nested-PCR. RESULTS: Of the 92 pregnant women included, five of them (5.43%) were colonized by Pneumocystis. Pneumocystis DNA was not found in any of the 87 available newborn samples or in the placentas of the five women who had a positive result by PCR in their upper respiratory samples. CONCLUSIONS: It was found that 5.43% of the pregnant women were colonized by Pneumocystis, there was no evidence of any role of this colonization in the transmission to their newborns, since none of them tested positive for Pneumocystis.
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Pneumocystis carinii/isolamento & purificação , Adulto , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Peru , Reação em Cadeia da Polimerase , Gravidez , Adulto JovemRESUMO
Follicular atresia is the mechanism by which the oocyte contents are degraded during oogenesis in response to stress conditions, allowing the energetic resources stored in the developing oocytes to be reallocated to optimize female fitness. Autophagy is a conserved intracellular degradation pathway where double-membrane vesicles are formed around target organelles leading to their degradation after lysosome fusion. The autophagy-related protein 8 (ATG8) is conjugated to the autophagic membrane and has a key role in the elongation and closure of the autophagosome. Here we identified one single isoform of ATG8 in the genome of the insect vector of Chagas Disease Rhodnius prolixus (RpATG8) and found that it is highly expressed in the ovary during vitellogenesis. Accordingly, autophagosomes were detected in the vitellogenic oocytes, as seen by immunoblotting and electron microscopy. To test if autophagosomes were important for follicular atresia, we silenced RpATG8 and elicited atresia in vitellogenic females by Zymosan-A injections. We found that silenced females were still able to trigger the same levels of follicle atresia, and that their atretic oocytes presented a characteristic morphology, with accumulated brown aggregates. Regardless of the difference in morphology, RpATG8-silenced atretic oocytes presented the same levels of protein, TAG and PolyP, as detected in control atretic oocytes, as well as the same levels of acidification of the yolk organelles. Because follicular atresia has the ultimate goal of restoring female fitness, we tested if RpATG8-silenced atresia would result in female physiology and behavior changes. Under insectarium conditions, we found that atresia-induced control and RpATG8-silenced females present no changes in blood meal digestion, survival, oviposition, TAG content in the fat body, haemolymph amino acid levels and overall locomotor activity. Altogether, we found that autophagosomes are formed during oogenesis and that the silencing of RpATG8 impairs autophagosome biogenesis in the oocytes. Nevertheless, regarding major macromolecule degradation and adaptations to the fitness costs imposed by triggering an immune response, we found that autophagic organelles are not essential for follicle atresia in R. prolixus.
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Autofagossomos , Atresia Folicular/fisiologia , Inativação Gênica , Proteínas de Insetos/metabolismo , Rhodnius/fisiologia , Animais , Feminino , Atresia Folicular/genética , Proteínas de Insetos/genética , Oócitos , Ovulação/fisiologia , Rhodnius/genética , VitelogêneseRESUMO
BACKGROUND AND OBJECTIVES: Smokers currently have no defined restrictions for blood donation. However, cigarette smoke contains toxic substances such as carbon monoxide (CO) and trace elements that can affect the packed red blood cells (PRBCs) quality and safety of transfusion. This study evaluated the effects of smoking on the concentration of essential and trace elements and on carboxyhemoglobin (COHb) levels in PRBCs from smoker donors. MATERIALS AND METHODS: A matched case-control study was conducted to compare COHb levels, determined by the CO-oximetry method, and levels of trace (Cd, Pb, Cr, Ni, As and Hg) and essential (Ca, Mg, Cu, Fe, Mn, Mo, Se and Zn) elements evaluated by inductively coupled plasma mass spectrometry, in PRBCs from smoker (n = 36) and non-smoker (n = 36) donors at Hospital de Clínicas de Porto Alegre, Brazil. RESULTS: Mean COHb level was 14 times higher in the PRBCs obtained from smoker donors (5·9 [4·0-9·1] vs. 0·4 [0·2-0·8]%). Cadmium (1·0 [1·0-1·8] µg/l vs. undetectable) and lead (27 [21-36] vs. 19 [14-26] µg/l) levels were significantly higher in the PRBCs from smokers. Moreover, except for molybdenum, levels of all essential elements were lower in smoker PRBCs. CONCLUSION: The PRBCs donated by smokers contain toxic elements that are probably not safe for transfusion in children. Our results might support changes in the current guidelines of blood banks to improve the transfusion safety through inclusion of inquiry about smoking in the clinical screening, labelling and reserve PRBCs from smoker donors for adults or less critical recipients.
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Doadores de Sangue/estatística & dados numéricos , Fumantes/estatística & dados numéricos , Fumar/sangue , Oligoelementos/sangue , Reação Transfusional/epidemiologia , Adulto , Bancos de Sangue/normas , Estudos de Casos e Controles , Eritrócitos/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/epidemiologiaRESUMO
The study described Pneumocystis jirovecii (P. jirovecii) multilocus typing in seven AIDS patients living in French Guiana (Cayenne Hospital) and seven immunosuppressed patients living in Brest, metropolitan France (Brest Hospital). Archival P. jirovecii specimens were examined at the dihydropteroate synthase (DHPS) locus using a PCR-RFLP technique, the internal transcribed spacer (ITS) 1 and ITS 2 and the mitochondrial large subunit rRNA (mtLSUrRNA) gene using PCR and sequencing. Analysis of typing results were combined with an analysis of the literature on P. jirovecii mtLSUrRNA types and ITS haplotypes. A wild DHPS type was identified in six Guianese patients and in seven patients from metropolitan France whereas a DHPS mutant was infected in the remaining Guianese patient. Typing of the two other loci pointed out a high diversity of ITS haplotypes and an average diversity of mtLSUrRNA types in French Guiana with a partial commonality of these haplotypes and types described in metropolitan France and around the world. Combining DHPS, ITS and mtLSU types, 12 different multilocus genotypes (MLGs) were identified, 4 MLGs in Guianese patients and 8 MLGs in Brest patients. MLG analysis allows to discriminate patients in 2 groups according to their geographical origin. Indeed, none of the MLGs identified in the Guianese patients were found in the Brest patients and none of the MLGs identified in the Brest patients were found in the Guianese patients. These results show that in French Guiana (i) PCP involving DHPS mutants occur, (ii) there is a diversity of ITS and mtLSUrRNA types and (iii) although partial type commonality in this territory and metropolitan France can be observed, MLG analysis suggests that P. jirovecii organisms from French Guiana may present specific characteristics.
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Síndrome da Imunodeficiência Adquirida/virologia , Tipagem de Sequências Multilocus/métodos , Pneumocystis carinii/classificação , Pneumocystis carinii/genética , Pneumonia por Pneumocystis/virologia , Síndrome da Imunodeficiência Adquirida/complicações , Adulto , Idoso , Feminino , França , Guiana Francesa , Variação Genética , Genoma Viral , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Pneumocystis carinii/isolamento & purificação , Estudos RetrospectivosRESUMO
A high prevalence of Pneumocystis jirovecii colonization was observed in patients positive for the human immunodeficiency virus (HIV) admitted to a tertiary hospital in southern Brazil between August 2012 and December 2012. Amplification of the mitochondrial large subunit ribosomal RNA gene in oropharyngeal samples through nested polymerase chain reaction identified P. jirovecii colonization in 26 of 58 (44.8%) HIV-positive patients admitted for causes other than Pneumocystis pneumonia. Colonization was more frequent among patients with an absolute CD4 count ≤200 cells/µl. These findings suggest that the HIV-infected population is a major reservoir and source of P. jirovecii infection and that identification of such individuals may contribute to future strategies for improving management of HIV-infected patients.
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Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Portador Sadio/epidemiologia , Pneumocystis carinii , Pneumonia por Pneumocystis/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Adulto , Brasil/epidemiologia , Portador Sadio/microbiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Orofaringe/microbiologia , Pneumocystis carinii/genética , Pneumocystis carinii/isolamento & purificação , Pneumonia por Pneumocystis/microbiologia , PrevalênciaRESUMO
Pneumocystis jirovecii is a leading cause of opportunistic infections among immunocompromised patients. The aim of this study was to determine the genetic diversity of P. jirovecii from colonized Cuban infants and toddlers by analysis of four genetic loci: mitochondrial large subunit (mtLSU) rRNA, cytochrome b (CYB), superoxide dismutase (SOD) and ß-tubulin (ß-tub). We determined the multilocus profiles based on concatenated genotype data (multilocus genotype; MLG) and nucleotide sequences (multilocus sequence analysis; MLSA) respectively, calculated the discriminatory power of each analysis, and investigated possible associations with demographic and clinical data. Sixteen of 51 PCR-positive nasopharyngeal swab specimens (years 2010-2013) with high P. jirovecii load were selected for downstream analysis. In mixed allelic profiles all genotypes/nucleotide sequence patterns were considered separately. All samples could be genotyped based on mtLSU, CYB and ß-tub locus. However, the SOD locus could be successfully amplified in only 7/16 (44%) specimens. Eight different P. jirovecii MLGs were identified among the 16 cases and eight samples presented identical MLG (MLG 1). Seventeen MLSA profiles were distinguished. No statistical association between genotypes or MLGs and demographic or clinical data could be identified. For MLSA the higher discriminatory power (S=0.976) was observed. The combination of mtLSU, CYB and ß-tub loci proved to be useful for molecular epidemiology studies of P. jirovecii. A total of 17 different MLSA profiles observed in 16 specimens indicated high genetic variability of P. jirovecii circulating in colonized Cuban infants and toddlers.
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Pneumocystis carinii/genética , Pneumonia por Pneumocystis/microbiologia , Cuba/epidemiologia , DNA Fúngico/análise , DNA Fúngico/genética , Feminino , Variação Genética , Genótipo , Humanos , Lactente , Masculino , Pneumocystis carinii/classificação , Pneumocystis carinii/isolamento & purificação , Pneumonia por Pneumocystis/epidemiologiaRESUMO
This study describes the prevalence and genotype distribution of Pneumocystis jirovecii obtained from nasopharyngeal (NP) swabs from immunocompetent Cuban infants and toddlers with whooping cough (WC). A total of 163 NP swabs from 163 young Cuban children with WC who were admitted to the respiratory care units at two pediatric centers were studied. The prevalence of the organism was determined by a quantitative PCR (qPCR) assay targeting the P. jirovecii mitochondrial large subunit (mtLSU) rRNA gene. Genotypes were identified by direct sequencing of mtLSU ribosomal DNA (rDNA) and restriction fragment length polymorphism (RFLP) analysis of the dihydropteroate synthase (DHPS) gene amplicons. qPCR detected P. jirovecii DNA in 48/163 (29.4%) samples. mtLSU rDNA sequence analysis revealed the presence of three different genotypes in the population. Genotype 2 was most common (48%), followed in prevalence by genotypes 1 (23%) and 3 (19%); mixed-genotype infections were seen in 10% of the cases. RFLP analysis of DHPS PCR products revealed four genotypes, 18% of which were associated with resistance to sulfa drugs. Only contact with coughers (prevalence ratio [PR], 3.51 [95% confidence interval {CI}, 1.79 to 6.87]; P = 0.000) and exposure to tobacco smoke (PR, 1.82 [95% CI, 1.14 to 2.92]; P = 0.009) were statistically associated with being colonized by P. jirovecii. The prevalence of P. jirovecii in infants and toddlers with WC and the genotyping results provide evidence that this population represents a potential reservoir and transmission source of P. jirovecii.
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Infecções por Pneumocystis/epidemiologia , Infecções por Pneumocystis/microbiologia , Pneumocystis carinii/classificação , Pneumocystis carinii/isolamento & purificação , Coqueluche/complicações , Criança , Pré-Escolar , Cuba/epidemiologia , DNA Fúngico/química , DNA Fúngico/genética , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Dados de Sequência Molecular , Nasofaringe/microbiologia , Pneumocystis carinii/genética , Polimorfismo de Fragmento de Restrição , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Coqueluche/microbiologiaRESUMO
A high rate of Pneumocystis jirovecii colonization was observed in Brazilian cystic fibrosis (CF) patients (13 out of 34; 38.2%) who underwent bronchoscopy between March 2006 and August 2009 at the Hospital de Clinicas de Porto Alegre, Brazil. Bronchoalveolar lavage samples were collected from these patients and studied by nested PCR amplification of the mitochondrial gene coding for the large subunit ribosomal RNA (mtLSUrDNA). The observed rate of colonization was higher than that reported in European populations. Genotypic characterization of the mtLSUrDNA locus revealed a predominance of the polymorphisms 85C/248C (genotype 1) and 85T/248C (genotype 3), with all samples possessing the wild-type genotype of dihydropteroate synthase. These findings suggest that cystic fibrosis patients could be an important reservoir and source of P. jirovecii infection. Further studies are required to elucidate the role of this common fungal colonization in the evolution of CF patients.
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Fibrose Cística/microbiologia , Pneumocystis carinii/isolamento & purificação , Pneumonia por Pneumocystis/epidemiologia , Adolescente , Adulto , Brasil/epidemiologia , Criança , Pré-Escolar , Fibrose Cística/complicações , Fibrose Cística/epidemiologia , DNA Fúngico/genética , DNA Mitocondrial/genética , DNA Ribossômico/genética , Feminino , Genes de RNAr , Humanos , Lactente , Masculino , Pneumocystis carinii/genética , Pneumonia por Pneumocystis/complicações , Pneumonia por Pneumocystis/microbiologia , Reação em Cadeia da Polimerase , Prevalência , Análise de Sequência de DNA , Adulto JovemRESUMO
Genotypes of two different loci of the Pneumocystis jirovecii mitochondrial gene were studied in specimens from a total of 75 Pneumocystis pneumonia patients in Spain, France and Cuba. A new genotype of the mitochondrial small subunit rRNA gene of P. jirovecii (160A/196T) was identified, which was revealed to be the most common in these three countries, especially in Cuba where its proportion reached 93.8%. Our data imply that the new genotype might be circulating worldwide and also suggests that the distribution of P. jirovecii genotypes could be narrower in islands such as Cuba.