Determination of NAT2 Genotypes in a Cohort of Patients with Suspected TB in the State of Rio de Janeiro.

The human N-acetyltransferase 2 enzyme, encoded by the NAT2 gene, plays an important role in the metabolism of isoniazid, the main drug used to treat tuberculosis. The interindividual variation in the response of patients to drug treatment for tuberculosis may be responsible for the occurrence of unfavorable outcomes. The presence of polymorphisms in genes associated with the metabolism and transport of drugs, receptors, and therapeutic targets has been identified as a major determinant of this variability. The objective of this study was to identify the genetic profile of NAT2 in the study population. Using the obtained genomic DNA followed by PCR amplification and sequencing, the frequency of nine SNPs as well as alleles associated with slow (47.9%), intermediate (38.7%), and fast acetylation phenotypes (11.3%), in addition to those whose phenotype has not yet been characterized (2.1%), was estimated. The NAT2*5B allele was identified more frequently (31.3%). The description of SNPs in pharmacogenes and the establishment of their relationship with the pharmacokinetics of an individual offer an individualized approach that allows us to reduce the unfavorable outcomes of a therapy, ensure better adherence to treatment, prevent the emergence of MDR strains, reduce the cost of treatment, and improve the quality of patients' lives.

Genetic Diversity of Legionella pneumophila Isolates from Artificial Water Sources in Brazil.

Legionella pneumophila (Lp) is a Gram-negative bacterium found in natural and artificial aquatic environments and inhalation of contaminated aerosols can cause severe pneumonia known as Legionnaires' Disease (LD). In Brazil there is hardly any information about this pathogen, so we studied the genetic variation of forty Legionella spp. isolates obtained from hotels, malls, laboratories, retail centers, and companies after culturing in BCYE medium. These isolates were collected from various sources in nine Brazilian states. Molecular identification of the samples was carried out using Sequence-Based Typing (SBT), which consists of sequencing and analysis of seven genes (flaA, pilE, asd, mip, mompS, proA, and neuA) to define a Sequence Type (ST). Eleven STs were identified among 34/40 isolates, of which eight have been previously described (ST1, ST80, ST152, ST242, ST664, ST1185, ST1464, ST1642) and three were new STs (ST2960, ST2962, and ST2963), the former identified in five different cooling towers in the city of São Paulo. The ST1 that is widely distributed in many countries was also the most prevalent in this study. In addition, other STs that we observed have also been associated with legionellosis in other countries, reinforcing the potential of these isolates to cause LD in Brazil. Unfortunately, no human isolates could be characterized until presently, but our observations strongly suggest the need of surveillance implementation system and control measures of Legionella spp. in Brazil, including the use of more sensitive genotyping procedures besides ST.

Use of cerebrospinal fluid CXCL13 concentration for diagnosis and monitoring of neurosyphilis: a three-case report

Introduction: Previous retrospective studies have demonstrated that the concentration of chemokine ligand CXCL13 in cerebrospinal fluid (CSF-CXCL13) is a promising biomarker in the diagnosis of neurosyphilis and, additionally, in the monitoring of therapeutic efficacy. Objective: To describe three cases of patients with neurosyphilis (NS) treated at Hospital Universitário Gaffrée e Guinle, in Rio de Janeiro, Brazil, with suspected active syphilis with neurological symptoms. Case report: Three patients from Rio de Janeiro, Brazil, were investigated for symptomatic NS. The concentration of CSF-CXCL13 was prospectively performed by enzyme-linked immunosorbent assay (ELISA) in all participants at baseline and in follow-up visits at 3 months after therapy. CSF-CXCL13 concentrations were significantly higher in all three patients with established NS. The CSF-CXCL13 concentrations decreased after 3 months of therapy compared to baseline in all cases reported. The added high concentration of CSF-CXCL13 plus CSF-TPHA reactivity above 1:40 titer agreed with the diagnosis of NS in 100% of the cases. Conclusion: In this case series, we present three cases of NS diagnosed using CXCL13 in CSF as a complementary test. These case series suggest that the clinical use of CSF-CXCL13 is useful as a supplementary biomarker for NS and for monitoring the effectiveness of NS therapy, especially in patients with nonreactive CSF-VDRL, excluding other neurologic diseases

Heterogeneous persistence of Mycobacterium leprae in oral and nasal mucosa of multibacillary patients during multidrug therapy.

BACKGROUND: Leprosy is curable by multidrug therapy (MDT) treatment regimen ranging from six to 12 months. The variable levels of tolerance and adherence among patients can, however, result in treatment failure and the emergence of drug-resistant strains. OBJECTIVES: Describe the impact of MDT over Mycobacterium leprae viability in patient's oral and nasal mucosa along treatment. METHODS: Mycobacterium leprae viability was monitored by quantitative polymerase chain reaction (qPCR) quantification of 16S rRNA in lateral and contralateral scrapings of oral and nasal mucosa of 10 multibacillary patients along the initial five months of treatment. FINDINGS: The results demonstrated high heterogenicity of M. leprae viability among patients and between nasal and oral samples. Of six patients who presented good adherence and tolerance to the treatment, only four displayed absence of M. leprae viability in both samples three months after the first MDT dose, while for the other two, the absence of M. leprae viability in the oral and nasal cavities was only detected five months after the first dose. MAIN CONCLUSIONS: We concluded that qPCR of 16S rRNA for the determination of M. leprae viability in nasal and oral scraping samples could represent an interesting approach to monitor treatment efficacy.

Heterogeneous persistence of Mycobacterium leprae in oral and nasal mucosa of multibacillary patients during multidrug therapy

BACKGROUND Leprosy is curable by multidrug therapy (MDT) treatment regimen ranging from six to 12 months. The variable levels of tolerance and adherence among patients can, however, result in treatment failure and the emergence of drug-resistant strains. OBJECTIVES Describe the impact of MDT over Mycobacterium leprae viability in patient's oral and nasal mucosa along treatment. METHODS Mycobacterium leprae viability was monitored by quantitative polymerase chain reaction (qPCR) quantification of 16S rRNA in lateral and contralateral scrapings of oral and nasal mucosa of 10 multibacillary patients along the initial five months of treatment. FINDINGS The results demonstrated high heterogenicity of M. leprae viability among patients and between nasal and oral samples. Of six patients who presented good adherence and tolerance to the treatment, only four displayed absence of M. leprae viability in both samples three months after the first MDT dose, while for the other two, the absence of M. leprae viability in the oral and nasal cavities was only detected five months after the first dose. MAIN CONCLUSIONS We concluded that qPCR of 16S rRNA for the determination of M. leprae viability in nasal and oral scraping samples could represent an interesting approach to monitor treatment efficacy.

Genotypic Characterization of Mycobacterium bovis Isolates From Dairy Cattle Diagnosed With Clinical Tuberculosis.

Molecular diagnosis of bovine tuberculosis plays an essential role in the epidemiological knowledge of the disease. Bovine tuberculosis caused by Mycobacterium bovis represents a risk to human health. This study aimed to perform the genotypic characterization of M. bovis isolated from bovines diagnosed as tuberculosis from dairy herds in the state of Pernambuco, Brazil. Granulomas from 30 bovines were sent for microbiological culture, and colonies compatible with Mycobacterium spp. were obtained in at least one culture from 17/30 granulomas. All isolates were confirmed to be M. bovis by spoligotyping and 24loci MIRU-VNTR typing. While spoligotyping characterized the isolates as SB0121, SB0295, SB0852, SB0120, and an unclassified genotype, 24loci MIRU-VNTR rendered two clusters of two isolates each and 13 unique profiles. Loci ETR-A showed higher discriminatory power, and loci (ETR-B, ETR-C, MIRU16, MIRU27, and QUB26) showed moderate allelic diversity. This is the first study on the genetic variability of the infectious agent cause of bovine TB in Pernambuco and demonstrates variability of strains in the state. Thus, it corroborates the importance of this microorganism as agent of bovine tuberculosis and its zoonotic potential, this epidemiological tool being a determinant in the rigor of the sanitary practices of disease control in dairy herds.

Mixed infection and two different resistance profiles of Treponema pallidum to macrolides identified in some clinical specimens of the same patient / Infecção mista e resistência diferente a macrolídeos em Treponema pallidum identificadas por variadas espécimes clínicos em um mesmo paciente

Syphilis represents a global public health problem. The resistance of Treponema pallidum to macrolides is related to the mutation in the 23S rRNA gene (A2058G). We reported a case of secondary syphilis in a 52-year-old man presenting two profiles: the first one of susceptibility, and the other one of resistance, when we analyzed the 23S rRNA gene sequence from two different clinical specimens of the same infectious episode. DNA from T. pallidum from skin biopsy presented resistance profile, whereas T. pallidum DNA from blood presented a profile of susceptibility to macrolides. These results suggest it was mixed infection or reinfection.

A sífilis representa um problema de saúde pública mundial. A resistência de Treponema pallidum aos macrolídeos está relacionada à mutação no gene 23S rRNA (A2058G). Relatamos um caso de sífilis secundária, em um homem de 52 anos, com um perfil de suscetibilidade e outro de resistência, ao analisarmos a sequência do gene 23S rRNA de dois espécimes clínicos diferentes, do mesmo episódio infeccioso. A amostra de DNA de T. pallidum proveniente de raspado dérmico da lesão apresentou um perfil de resistência, enquanto aquele que derivou de sangue apresentou perfil de suscetibilidade aos macrolídeos. Esses resultados sugerem tratar-se de infecção mista ou de reinfecção.

Avaliação dos fenótipos de acetilação e hidroxilação predominantes nas populações de cinco macrorregiões do Brasil baseada no genoma: possível influência da farmacogenética na conduta terapêutica da hanseníase / Evaluation of acetylation and hydroxylation phenotypes predominant in the populationsof five geographical regions of Brazil based on the genome: possible influence ofpharmacogenetics in the therapeutic management of leprosy

A hanseníase é uma doença infecciosa crônica, com alto poder incapacitante. O tratamento sebaseia na combinação de três drogas: dapsona, rifampicina e clofazimina, porém, a ocorrênciade reações adversas (ADRs) induzidas principalmente pela dapsona (~70%) é frequentementeobservada. Dentre as ADRs destacam-se: a metemoglobinemia, anemia hemolítica, a hepatitee a síndrome da dapsona. A metabolização da dapsona é baseada em reações enzimáticas deacetilação e hidroxilação, catalisadas, pelas enzimas N-acetiltransferase2 (NAT2) ehidroxilases do citocromo P450 (CYPs). Dentre os vários fatores associados à ocorrência deADRs, o fator genético é primordial. Polimorfismos presentes em genes que codificam paraenzimas metabolizadoras de drogas podem representar alto risco para este desfecho.Paralelamente, outro aspecto importante é a alta variabilidade genética ligada à etnia. O Brasilé um país composto por uma população altamente miscigenada com alta diversidade genética.Sendo a hanseníase uma doença endêmica tratada com um esquema padronizado para toda apopulação, a avaliação destes perfis genéticos é de fundamental relevância para a prevençãode ADRs. Este estudo teve como principal objetivo descrever a variabilidade dos genes NAT2,CYP2E1, CYP3A4 e CYP3A5 em coortes de pacientes de hanseníase provenientes das cincodiferentes macrorregiões do Brasil e realizar um estudo de associação, do tipo caso-controle,entre as variáveis genéticas presentes nesses genes com a ocorrência de reações adversas empacientes com hanseníase em tratamento com esquemas contendo dapsona. Um total de 964indivíduos foram incluidos no estudo descritivo de NAT2 enquanto para o estudo deassociação variou dependendo da região. Vinte e três SNPs de NAT2, foram identificadosnas populações estudadas, dos quais sete: 191 G>A; 282 C>T; 341T>C; 481 C>T; 590 G>A;803 A>G e 857 G>A, são os mais frequentes na população mundial...

Leprosy is a chronic infectious disease with high disabling potential. The treatment is basedon the combination of three drugs: dapsone, rifampicin and clofazimine, however, theoccurrence of adverse drug reactions (ADRs) mainly induced by dapsone (~70%) isfrequently observed with a predominance of methemoglobinemia, hemolytic anemia, hepatitisand dapsone syndrome. The dapsone metabolization is mediated by acetylation andhydroxylation enzymatic reactions catalyzed by the N-acetyltransferase 2 (NAT2) andcytochrome P450 (CYPs). Among the various factors associated with the occurrence ofADRs, the genetic factor is essential. Polymorphisms in genes encoding drug metabolizingenzymes may represent a high risk for this outcome. In paralell, another important aspect isthe high genetic variability related to ethnicity. Brazil is composed of a high mixed populationwith high levels of genetic diversity. Being leprosy is an endemic disease which treatment isa standard regimen for the entire population, the evaluation of these genetic profiles becamerelevant for prevention of ADRs. The main goals of this study was to describe the geneticvariability of NAT2, CYP2E1, CYP3A4 and CYP3A5 in cohorts of leprosy patients from fiveBrazilian geographical regions and to perform an association study (case-control) between thegenetic variants present in these genes and occurrence of ADRs in leprosy patients treatedwith dapsone-containing schemes. A total of 964 individuals were enrolled to the descriptivestudy for NAT2 while for the association study the sample size varied according to theregion.Twenty-three SNPs in NAT2, were identified in the study populatuion, seven of which191 G> A; 282 C> T; 341T> C; 481 C> T; 590 G> A; 803 A> G and 857 G>A are the mostfrequent in the world population...