Analysis of the clonal relationship among clinical isolates of Salmonella enterica serovar Infantis by different typing methods

Salmonella Infantis has been the second most common serovar in Argentina in the last two years, being isolated mostly from paediatric hospitalised patients. In order to determine the clonal relationship among Salmonella Infantis strains, we examined 15 isolates from paediatric patient faeces in Argentina (12 geographically related and 3 geographically non-related) by using antimicrobial susceptibility, plasmid profiling, repetitive extragenic palindromic (REP) PCR, enterobacterial repetitive intergenic consensus (ERIC) PCR, and low-frequency restriction analysis of chromosomal DNA by pulsed field gel electrophoresis (PFGE). Four Spanish strains were included as controls of clonal diversity in molecular techniques. Antibiotype and plasmid profile was not useful as epidemiological tools. PFGE and REP-PCR were able to discriminate between Argentinean and Spanish isolates of Salmonella Infantis allowing to detect genetically related strains in three different cities. This finding indicates that a possible spread of a clone of this serovar in the North-eastern Region of Argentina has taken place in 1998.

Tradição oral e litaratura bíblica

pp. 163-175

Complicações Hemorrágicas e/ou Tromboembólicas em Doentes sob Anticoagulação Oral Regularmente Seguidos em Consulta Diferenciada

A consulta de hipocoagulação de um hospital central contempla uma população bastante diversificada, pelo que uma melhor compreensão das características da mesma, poderá levar à melhoria da prestação de cuidados de saúde e à diminuição do número de complicações tromboembólicas (resultantes da patologia base) e hemorrágicas [resultantes da própria terapêutica anticoagulante (ACO)]. Objectivos: Avaliar as características da população que frequenta a consulta de hipocoagulação e analisar quais podem predizer um maior risco de complicações. Métodos: Utilizaram-se os dados colhidos por um médico através de um questionário colocado a doentes durante a consulta de hipocoagulação. Foram efectuados 101 questionários e avaliaram-se as características demográficas (sexo, idade, escolaridade, grau de analfabetismo), os factores de risco clássicos para doença coronária, o diagnóstico que levou ao início da ACO, a duração da ACO, a periodicidade da determinação e valores mínimos, máximos e à data do questionário de INR e as complicações desta terapêutica. Consideraram-se como complicações o aparecimento de fenómenos hemorrágicos e/ou tromboembólicos, no decurso da terapêutica hipocoagulante. Resultados: Foram estudados 101 doentes, 74 do sexo feminino (73,3%), com idade média de 6410 anos (21-85). A população analisada tinha 4,5 ± 3,5 anos de escolaridade, com 15% de analfabetismo. A maioria dos doentes iniciou ACO após colocação de prótese valvular mecânica (56,4%). Em cada doente existia em média 1 factor de risco para doença coronária. O número de meses de ACO era de 99,489 (1-360). Sessenta e seis doentes (65,3%) conheciam o motivo pelo qual iniciaram esta terapêutica. Cada doente tinha efectuado 1,20,6 determinações de INR por mês e tinha, em média, um tempo máximo sem verificação do mesmo de 6,210,4 semanas. Quarenta e cinco doentes sofreram alguma complicação tromboembólica e/ou hemorrágica no decurso da terapêutica ACO. Ocorreram 50 complicações hemorrágicas, em 41 doentes, das quais 7 motivaram internamento. Detectaram-se 7 episódios de tromboembolismo central ou periférico, em 7 doentes. Posteriormente, dividiu-se a população em dois grupos: grupo I – com complicações (GI) e grupo II – sem complicações (GII). GI – 45 doentes, idade média 63,59,1 anos (39-80) e GII – 56 doentes, idade média 64,711,3 anos (21-85). Nos doentes que iniciaram ACO por prótese mitral detectou-se um maior número de complicações (60,6% no GI e 39,4% no GII, p=0,024). Também nos doentes com INR máximo recomendado > 3 (55,2% no GI e 44,8% no GII, p=0,013) e nos que tinham sido sujeitos a terapêutica estomatológica (68,3% no GI e 31,7% no GII, p<0,001) se verificou um maior número de complicações. A duração da ACO foi o factor mais significativo para o aparecimento de complicações (GI – 138,196,5 meses, GII – 67,868,2 meses, p <0,00005). Na análise multivariada apenas a duração da ACO se manteve como factor preditivo independente. Conclusões: Na população existe uma percentagem importante de doentes com baixa escolaridade, que se poderá repercutir sobre a compreensão desta terapêutica específica, não tendo contudo, neste estudo, revelado influência significativa na taxa de complicações. O aparecimento de complicações durante a terapêutica anticoagulante é dependente da duração desta, do valor do INR máximo recomendado e da realização ou não de procedimentos estomatológicos, sendo o primeiro factor o mais significativo.

Oral cysticercosis: case report and review of the literature

Cysticercosis is a condition that occurs when man is infested by the larvae of Taenia solium, acting as an intermediate host instead of definitive. Oral cysticercosis is a rare event, and it represents a difficulty in clinical diagnosis. A case of oral cysticercosis in a 23-year-old white female who presented a painless swelling in the dorsal portion of the tongue is reported. An excisional biopsy was performed and histopathological examination revealed a cystic cavity containing the tapeworm.

Carbohydrate assimilation profiles of Brazilian Candida dubliniensis isolates based on ID 32C system

The purpose of the present study was to evaluate the identification of 19 Brazilian C. dubliniensis based on the biochemical profile exhibited when tested by the commercial identification kit ID 32C (bioMerieux). Thirteen of the isolates were rigorously identified as C. dubliniensis and the remaining isolates (six) were considered as having a doubtful profile but the software also suggested that there was 83.6% of chances for them to be C. dubliniensis. As well as pointed by the literature the identification obtained by phenotypic tests should be considered presumptive for C. dubliniensis due to variability of this new species.

Antifungal susceptibilities of clinical and environmental isolates of Cryptococcus neoformans in goiânia city, Goiás, Brasil

We evaluated the antifungal activities of amphotericin B, fluconazole, itraconazole and voriconazole in 70 Cryptococcus neoformans strains obtained from cerebrospinal fluid from AIDS patients and 40 C. neoformans strains isolated from the environment. Four clinical isolates were identified as C. neoformans var. gattii. The susceptibility test was done using a broth microdilution method according to NCCLS M27-A2. Range minimal inhibitory concentrations (MICs) for C. neoformans clinical isolates were 0.06-1.0 µg/mL for amphotericin B, 0.125-8 µg/mL for fluconazole, 0.03-0.5 µg/mL for itraconazole and 0.03-0.25 µg/mL for voriconazole. C. neoformans environmental isolates showed range MICs 0.015-0.125 µg/mL, 0.25-2.0 µg/mL, 0.007-0.125 µg/mL and 0.03-0.25 µg/mL for amphotericin B, fluconazole, itraconazole and voriconazole respectively. The MICs results obtained from clinical and environmental isolates showed similar pattern of susceptibility and no resistance has been found in our isolates.

Virulence profile of ten Paracoccidioides brasiliensis isolates: association with morphologic and genetic patterns

Ten isolates of Paracoccidioides brasiliensis were examined for differences in virulence in outbred mice intravenously inoculated with the fungus, associated with mycelial morphology, and genetic patterns measured by random amplified polymorphic DNA (RAPD). Virulence was evaluated by viable yeast cell recovery from lungs and demonstration of histopathologic lesions in different organs. The results showed that the isolates presented four virulence degrees: high virulence, intermediate, low and non-virulence. RAPD clustered the isolates studied in two main groups with 56% of genetic similarity. Strains with low virulence, Pb265 or the non-virulent, Pb192, showed glabrous/cerebriform morphology and high genetic similarity (98.7%) when compared to the other isolates studied. The same was observed with Bt79 and Bt83 that shared 96% genetic similarity, cottony colonies and high virulence. The RAPD technique could only discriminate P. brasiliensis isolates according to glabrous/cerebriform or cottony colonies, and also high from low virulence strains. Isolates with intermediate virulence such as Pb18, Pb18B6, Bt32 and Bt56 showed variability in their similarity coefficient suggesting that RAPD was able to detect genetic variability in this fungal specie. Virulence profile of P. brasiliensis demonstrated that both mycelial morphologic extreme phenotypes may be associated with fungal virulence and their in vitro subculture time. Thus, RAPD technique analysis employed in association with virulence, morphologic and immunologic aspects might prove adequate to detect differences between P. brasiliensis isolates.

Failure of nitric oxide production by macrophages and decrease in CD4+ T cells in oral paracoccidioidomycosis: possible mechanisms that permit local fungal multiplication

Paracoccidioidomycosis is a chronic granulomatous disease that induces a specific inflammatory and immune response. The participation of nitric oxide (NO), a product of the inducible nitric oxide synthase enzyme (iNOS), as an important fungicidal molecule against Paracoccidioides brasiliensis has been demonstrated. In order to further characterize the Oral Paracoccidioidomycosis (OP), we undertook an immunohistochemical study of iNOS+, CD45RO+, CD3+, CD8+, CD20+, CD68+ cells and mast cells. The samples were distributed in groups according to the number of viable fungi per mm². Our results showed weak immunolabeling for iNOS in the multinucleated giant cells (MNGC) and in most of the mononuclear (MN) cells, and the proportion of iNOS+ MN/MNGC cells in the OP were comparable to Control (clinically healthy oral tissues). Additionally, our analysis revealed a similarity in the number of CD4+ cells between the Control and the OP groups with higher numbers of fungi. These findings suggest that a low expression of iNOS and a decrease in the CD4+ T cells in OP may represent possible mechanisms that permit the local fungal multiplication and maintenance of active oral lesions.

Clinical guideline for diagnosis and management of melioidosis

Melioidosis is an emerging infection in Brazil and neighbouring South American countries. The wide range of clinical presentations include severe community-acquired pneumonia, septicaemia, central nervous system infection and less severe soft tissue infection. Diagnosis depends heavily on the clinical microbiology laboratory for culture. Burkholderia pseudomallei, the bacterial cause of melioidosis, is easily cultured from blood, sputum and other clinical samples. However, B. pseudomallei can be difficult to identify reliably, and can be confused with closely related bacteria, some of which may be dismissed as insignificant culture contaminants. Serological tests can help to support a diagnosis of melioidosis, but by themselves do not provide a definitive diagnosis. The use of a laboratory discovery pathway can help reduce the risk of missing atypical B. pseudomallei isolates. Recommended antibiotic treatment for severe infection is either intravenous Ceftazidime or Meropenem for several weeks, followed by up to 20 weeks oral treatment with a combination of trimethoprim-sulphamethoxazole and doxycycline. Consistent use of diagnostic microbiology to confirm the diagnosis, and rigorous treatment of severe infection with the correct antibiotics in two stages; acute and eradication, will contribute to a reduction in mortality from melioidosis.

Genetic diversity and antimicrobial resistance of enterococcal isolates from Southern region of Brazil

In the present study, a total of 455 enterococcal isolates, recovered from patients living in the city of Porto Alegre, State of Rio Grande do Sul, Brazil, during the period from July 1996 to June 1997, were identified to the species level by conventional biochemical and microbiological tests, and assayed for their susceptibilities to antimicrobial agents. The genetic diversity of antimicrobial resistant strains was evaluated by pulsed-field gel electrophoresis (PFGE) analysis of SmaI restricted chromosomal DNA. The most frequent species was Enterococcus faecalis (92.8%). Other species identified were: E. faecium (2.9%), E. gallinarum (1.5%), E. avium (1.1%), E. hirae (0.7%), E. casseliflavus (0.4%), E. durans (0.4%) and E. raffinosus (0.2%). The overall prevalence of isolates with high-level resistance (HLR) to aminoglycosides was 37.8%. HLR to gentamicin was found in 24.8%. No strains with acquired resistance to vancomycin were found. PFGE analysis showed the predominance of clonal group A, comprising strains isolated from different clinical specimens obtained from patients in three hospitals. These results suggest intra and inter-hospital dissemination of one predominant clonal group of E. faecalis isolates with HLR to gentamicin in the hospitals included in this study.