[SPECIFIC FEATURES OF ECOLOGY, PATHOGENIC PROPERTIES, AND ROLE OF THE STAPHYLOCOCCUS INTERMEDIUS GROUP MEMBERS IN ANIMAL AND HUMAN INFECTIOUS PATHOLOGY.]

The changes in the nomenclature of species in the genus Staphylococcus, including the most pathogenic cluster of the coagulase-positive staphylococci, are represented. Presently, besides S. aureus, this cluster consists of 6 species: S. intermedius, S. schleiferi ssp. coagulans, S. lutrae, S. hyicus, S. pseudintermedius, and S. delphini. A particular attention was paid to the Staphylococcus intermedius group (SIG), which includes three closely related coagulase-positive bacterial species: S. intermedius, S. pseudintermedius, and S. delphini. The hosts of SIG species are various mammals and birds, which live in a close contact with humans. The current knowledge about the virulence factors and pathogenicity for animals and humans are analyzed. The diffic6lties of the species identification, the features of ecology and epidemiology, antimicrobial resistance were reviewed. The biological features of S. pseudintermedius, which has the greatest similarity with S. aureus, are considered in the context of the properties of newly emerging pathogens.

Nasal carriage of coagulase positive staphylococci in patients of a Primary-Healthcare-Center: genetic lineages and resistance and virulence genes / / Staphylococcus coagulasa positiva en muestras nasales de pacientes de un centro de atención primaria: líneas genéticas y contenido en genes de resistencia y de virulencia

INTRODUCTION: Staphylococcus aureus and Staphylococcus pseudintermedius are highly important due to their capacity for producing diseases in humans and animals, respectively. The aim of the study was to investigate and characterize the coagulase positive Staphylococcus (CoPS) carriage in a Primary Healthcare Center population. METHODS: Nasal swabs were obtained from 281 non-infectious patients. The CoPS isolates recovered were typed, and their resistance phenotype and genotype, as well as their virulence profiles, were analyzed. RESULTS: CoPS isolates were recovered from 56/281 patients (19.9%). Fifty-five were S. aureus (19.6%), 54 were methicillin susceptible (MSSA) and one was methicillin resistant (MRSA). The remaining isolate was S. pseudintermedius (0.4%). A high diversity of spa-types (n = 40) was detected, with 6 of them being new ones. The multi-locus-sequence-typing of 13 MSSA and one MRSA selected isolates was performed and the STs detected were: ST8, ST15, ST30, ST34, ST121, ST146, ST398, ST554, ST942, ST2499, and ST2500 (the last two STs being new). One MSSA isolate was typed as t1197-ST398-(Clonal complex)CC398. The MRSA isolate was typed as t002-ST146-CC5-SCCmec-IVc, and exhibited a multiresistance phenotype. The detected resistances were: penicillin (76%), macrolides (7%), tetracycline (7%), trimethoprim-sulfamethoxazole (7%), quinolones (7%), and lincosamides (5%). Five isolates contained lukF/lukS-PV genes, 17 tst gene, one eta gene, and two etb gene. The S. pseudintermedius isolate presented a new spa-type (t57) (belonging to a new ST180) and the geneslukS/F-I, siet, se-int, and expB. CONCLUSIONS: A high genetic diversity of S. aureus was detected. Mention must be made of the identification of MSSA CC398 and S. pseudintermedius isolates in two patients, one of them with animal contact. The detection of the genes lukF/lukS-PV and tst should be noted

INTRODUCCIÓN: Staphylococcus aureus y Staphylococcus pseudintermedius son 2 especies de gran importancia que pueden producir enfermedades tanto en personas como en animales. El objetivo del trabajo fue estudiar el estado de portador nasal de aislados de Staphylococcus coagulasa positiva (SCoP) en pacientes de un centro de atención primaria. MÉTODOS: Se analizaron muestras nasales de 281 pacientes sin patología infecciosa. Se tiparon los aislados SCoP y se estudiaron sus fenotipos y genotipos de resistencia y sus perfiles de virulencia. RESULTADOS: Se aislaron SCoP en 56/281 pacientes (19,9%): 55 de los aislados fueron S. aureus (19,6%), 54 sensibles a la meticilina (SASM) y uno resistente a la meticilina (SARM). El aislado restante correspondió a S. pseudintermedius (0,4%). Se detectó una alta diversidad de tipos de spa (n = 40), identificándose 6 nuevos tipos. Se realizó el multi-locus-sequence-typing de 13 cepas SASM y una cepa SARM seleccionadas y se detectaron los siguientes STs: ST8, ST15, ST30, ST34, ST121, ST146, ST398, ST554, ST942, ST2499 y ST2500 (los 2 últimos nuevos). Una de las cepas SASM se tipó como t1197-ST398-(Clonal Complex)CC398. La cepa SARM se tipó como t002-ST146-CC5-SCCmec-IVc y mostró un fenotipo de multirresistencia. Se detectó resistencia a: penicilina (76%), macrólidos (7%), tetraciclina (7%), trimetoprim-sulfametoxazol (7%), quinolonas (7%) y lincosamidas (5%). Se identificaron los genes (número de cepas): lukF/lukS-PV (5), tst (17), eta (1) y etb (2). La cepa de S. pseudintermedius presentó un spa nuevo (t057), una secuencia tipo nueva (ST180), y contenía los genes lukS/F-I, siet, se-int y expB. CONCLUSIONES: Se detectó una alta diversidad genética entre los aislados de SASM. Destaca la identificación de una cepa SASM CC398 (en un veterinario) y otra de S. pseudintermedius, y la frecuente detección de los genes lukF/lukS-PV, tst, eta o etb entre las cepas SASM

Molecular characterization of Staphylococcus pseudintermedius strains isolated from clinical samples of animal origin.

The aim of this study was to determine the species distribution among 44 randomly selected clinical isolates (30 mecA-positive and 14 mecA-negative) of animal origin previously identified as Staphylococcus intermedius by phenotypic tests and species-specific PCR amplification of the 16S rRNA gene. For this purpose, we used a multiplex PCR for the detection of the nuc gene and restriction fragment length polymorphism analysis of pta gene amplified by PCR. Both methods allow discrimination of Staphylococcus pseudintermedius from the other closely related members of the S. intermedius group and other coagulase-positive staphylococci isolated from animals. Genetic diversity of S. pseudintermedius strains was analyzed by staphylococcal protein A-encoding gene (spa) typing. Multiplex PCR method was used to identify staphylococcal cassette chromosome mec (SCCmec) type in mecA-positive strains. All isolates previously identified as S. intermedius were shown to belong to S. pseudintermedius. According to PCR-based SCCmec typing, SCCmecIII was the most prevalent type (n = 23), and solely seven isolates were designated as non-typeable. Furthermore, the assessment of spa-typing results revealed that the majority of all strains (n = 27) harbored spa type t02, and 17 strains were classified as non-typeable.

Staphylococcus intermedius--rare pathogen of acute meningitis.

We report the first case of acute meningitis caused by a rare, atypical pathogen. An 11-month-old infant was admitted to hospital with clinical symptoms typical of acute meningitis. Cerebrospinal fluid analysis revealed an elevated neutrophil cell count and high proteins. Microbiological examination of the fluid confirmed an atypical cause of meningitis--Staphylococcus intermedius. Antibiotic therapy with cefotaxime was successful and the child made a full recovery.