Fazio Cecilia, Neri Arianna, Starnino Stefania, Sofia Tonino, Mastrantonio Paola, Stefanelli Paola
Department of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena, 299-00161 Rome, Italy.
New Microbiol. 2008 Oct;31(4):467-72.
The percentage of Neisseria meningitidis serogroup Y isolated from patients with invasive meningococcal disease (IMD) in Italy has increased from 1998 to 2006. In this study, phenotypic features and genetic relatedness have been investigated in all serogroup Y meningococci isolated during that period. Multilocus sequence typing (MLST) identified the ST-23 complex/Cluster A3 as the major clonal complex in 88.8% of the strains. That complex included all strains belonging to the sequence type (ST) 23 isolated from 1998 to 2004, whereas the ST-3171 was prevalent among strains in the years 2005 and 2006. The STs 23 and 3171 differ for only one nucleotide in the phosphoglucomutase (pgm) housekeeping gene. Over 80% of serogroup Y ST-23 complex/Cluster A3 strains showed phenotype Y:14:NST and 85% of the latter resulted indistinguishable by pulsed-field gel electrophoresis analysis. In 2005, serogroup Y meningococci with decreased susceptibility to penicillin were isolated for the first time in Italy. In the following year, three of the seven strains showed this phenotype. The results of this study allow us to draw a profile of the molecular characteristics of invasive serogroup Y in Italy and will be helpful to monitor the spread of this serogroup in the next years.
1998年至2006年期间，意大利侵袭性脑膜炎球菌病（IMD）患者中分离出的Y群脑膜炎奈瑟菌比例有所增加。在本研究中，对该时期分离出的所有Y群脑膜炎球菌的表型特征和遗传相关性进行了调查。多位点序列分型（MLST）确定ST-23复合体/A3簇为88.8%菌株中的主要克隆复合体。该复合体包括1998年至2004年分离出的所有属于序列型（ST）23的菌株，而ST-3171在2005年和2006年的菌株中占主导地位。ST23和3171在磷酸葡萄糖变位酶（pgm）管家基因中仅相差一个核苷酸。超过80%的Y群ST-23复合体/A3簇菌株表现出Y:14:NST表型，其中85%通过脉冲场凝胶电泳分析无法区分。2005年，意大利首次分离出对青霉素敏感性降低的Y群脑膜炎球菌。次年，七株菌株中有三株表现出这种表型。本研究结果使我们能够描绘出意大利侵袭性Y群的分子特征概况，并将有助于监测该菌群在未来几年的传播。
