ABSTRACTNeisseria meningitidisis a commensal and accidental pathogen exclusively of humans. Although the production of polysaccharide capsules is considered to be essential for meningococcal virulence, there have been reports of constitutively unencapsulated strains causing invasive meningococcal disease (IMD). Here we report the genome sequence of a capsule null locus (cnl) strain of sequence type 198 (ST-198), which is found in half of the reported cases of IMD caused bycnlmeningococcal strains.
Three group BNeisseria meningitidisisolates, recovered from meningococcal disease cases in Canada and typed as B:2c:P1.5, were characterized. Multilocus sequence typing showed that all three isolates were related because of an identical sequence type (ST) 573. Isolates typed as 2c:P1.5 are common in serogroup Y meningococci but rare in isolates from serogroups B or C. Although no serogroup Y isolates have been typed as ST-573, eight isolates showed five to six housekeeping gene alleles that were identical to that of ST-573. This suggested that the B:2c:P1.5 isolates may have originated from serogroup Y organisms, possibly by capsule switching.
In this report, we describe a case of interconnected clusters of invasive meningococcal disease due to Neisseria meningitidis serogroup B:P1.22,14:F5-1(ST-269) in young adults – a boyfriend and a girlfriend. The male was diagnosed with primary meningococcal septic arthritis of the right knee and the female was diagnosed with meningococcal meningitis with meningococcemia a few hours later. Both were hospitalized at the General Hospital Celje and treated with ceftriaxone, but with different outcomes; the female recovered completely, while the male will probably have long-term sequelae of septic arthritis.
SUMMARYThe main Neisseria meningitidis adhesion molecules, type IV pili (Tfp) and Neisseria adhesion A (NadA), play important roles in the pathogenesis of invasive meningococcal disease. PilE is the major Tfp subunit. In this study, the prevalence and genetic diversity of pilE and nadA were investigated in the prevalent serogroups and clonal complexes (CC) of N. meningitidis isolated in China. All serogroup A strains belonging to CC1 and CC5 and all CC11 serogroup W135 strains were clustered into class II PilE clades. All serogroup C and most of serogroup B isolates except CC8 and ST5642 were class I PilE clades. Class II pilE sequences were highly conserved. All isolates belonging to class I PilE isolates were nadA negative. However, nadA-positive strains were exclusively found in CC5 and CC11 isolates (class II PilE). This study showed that PilE and NadA may be related to epidemic or endemic meningococcal disease.
Invasive meningococcal disease due to ciprofloxacin-resistant Neisseria meningitidis Sequence Type 7926: the first case in Italy, likely imported