Örebro University Hospital

Transcription

1 Örebro University Hospital Department of Laboratory Medicine Susanne Jacobsson Date: Page 1 (8) Neisseria meningitidis 2014 Annual report concerning serogroup, genosubtype and antibiotic susceptibility for Swedish Neisseria meningitidis isolates and results with direct PCR for diagnosis of acute bacterial meningitis A total of 79 N. meningitidis (Nm) isolates from 76 patients or carriers were sent from the clinical diagnostic laboratories in Sweden, and examined at the National Reference Laboratory for Pathogenic Neisseria in Örebro during Isolates from the cerebrospinal fluid (CSF)/blood/other sterile sites were characterised from a total of 45 patients. The total picture of invasive meningococcal disease in Sweden for the year 2014 is reached by amalgamating of this report with the compulsatory clinical notifications sent to the Public Health Agency of Sweden. An annual publication in collaboration with the National Reference Laboratory in Örebro is published from the Public Health Agency of Sweden, Solna, including case fatality rate, age distribution and more ( Isolates of Nm from CSF/blood, puncture, throat/respiratory tract including the middle ear and urogenital in relation to serogroup is presented in Table I. One isolate per patient is presented. Table II shows the genosubtype results for the 45 invasive Nm isolates (CSF/blood), Table III displays the MIC reults for the 45 invasive Nm isolates. For a more longitudinal presentation, see Table IV. Genetic subtyping i.e. genosubtypning, was performed by sequencing the three most variable regions (VR1, VR2 and VR3) of the pora gene. We are also using a co-agglutination assay with a monoclonal antibody (4BG4-E7) that reacts with a conserved part of most PorA proteins, in order to document the presence of expressed protein in the outer membrane. All 45 invasive Nm isolates were genosubtypable, whereas PorA expression was detected in 37/45 (82%). Furthermore, multilocus sequencing typing (MLST) and feta typing are conducted and reported to European Centre for Disease Prevention and Control (ECDC). These data has since 2013 been obtained from whole genome sequencing using Miseq (Illumina) and the sequences were analysed using Bacterial Isolate Genome Sequence Database (BIGSdb) ( POSTAL ADDRESS VISITING ADDRESS PHONE ORG.NR Department of Laboratory Medicine, Microbiology Södra Grev Rosengatan +46-(0) Örebro University Hospital SE Örebro, Sweden Entrance F2 Örebro, Sweden FAX +46-(0) susanne.jacobsson@regionorebrolan.se INTERNET

2 Page 2 (8) PCR diagnosis for CSF, blood and other sterile sites, has been performed with a protocol detecting bacterial DNA, based on the 16S rrna gene, and species specific DNA, based on the ctra and crga genes for meningococci together with species specific genes for Streptococcus pneumoniae, Haemophilus influenzae, Streptococcus agalactiae and Listeria monocytogenes (2, 3). Nm isolates from cerebrospinal fluid and blood (number of patients=number of isolates) The 45 invasive isolates characterised during 2014 comprised of: 6 NmB isolates (1 sulphonamide resistant, i.e. MIC >10 mg/l) belonged to 6 different genosubtypes. 16 NmC isolates (12 sulphonamide resistant) belonged to 6 different genosubtypes, of which P1.5,2,36-2 predominated (n=9). 20 NmY isolates (6 sulphonamide resistant) belonged to 5 different genosubtypes, of which P1.5-2,10-1,36-2 predominated (n=15) 2 NmW isolates (2 sulphonamide resistant) belonged to P1.5,2, Nm29E isolate (sulphonamide sensitive) belonged to P1.5,2,36-2. Genosubtype distribution divided into serogroups is presented in Table II. Nm DNA in culture negative samples from normally sterile sites During 2014, 89 culture negative CSF and other samples were examined concerning meningococci, with PCR technique for bacterial DNA (2). Meningococcal DNA, the ctra and crga genes, was documented in 9 of the samples. The genogroup and genosubtype were diagnosed directly from the sample in 4 of these cases, where no additional culture samples was obtained (1). Antibiotic susceptibility All the Nm isolates were tested regarding antimicrobial susceptibility using Etest (Biomerieux) on Mueller-Hinton (BD) agar with blood (MH-F). MIC were obtained for benzylpenicillin (PcG), cefotaxime, chloramphenicol, ciprofloxacin, rifampicin and meropenem. As an additional epidemiological marker susceptibility to sulphonamides (sulphametoxazole) was also tested using Etest (Biomerieux). During 2014, the proportion of invasive Nm with reduced susceptibility to PcG (MIC >0.064 mg/l) was 10/45 (22%). See also Figure 1, where the number of invasive Nm isolates with reduced susceptibility for PcG from 2000 to 2014 are presented. All invasive isolates were susceptible to cefotaxime, chloramphenicol, ciprofloxacin, rifampicin and meropenem (Table III). No β-lactamase producing Nm has so far been isolated in Sweden.

3 Page 3 (8) Figure 1. The proportion (%) of invasive Nm with reduced sensitivity (MIC >0.064 mg/l) to PcG from 2000 to In conclusion In 2014, 49 cases of invasive meningococcal disease occurred in Sweden, 45 were culture confirmed and 4 were non-culture confirmed. The Y:P1.5-2,10-1,36-2 (n=15) together with C:P1.5,2,36-2 (n=9) were predominant among the culture confirmed meningococci causing invasive disease in Sweden during Compared to previous years (Table IV) the increase of the total number of meningococci seen from 2010, stalled during 2013 and the prevalence continued to decrease during Nm serogroup B (n=6) which is the lowest number in the latest decades. NmB prevalence has during the latest years been at a relatively low level. Since 2010, the mean number of invasive NmB isolates from CSF/blood have been 13, range 6-19 as compared to 22 per year, range during and 40, range during Nm serogroup C was isolated in 16 invasive cases, which is in the middle of the range since 2000 (10-22 isolates/year) and represents an increase from 2013 (n=13). The increasing incidence of invasive Nm serogroup Y observed since 2009 which appeared to stabilize during 2013 has now turned into a decrease and the prevalence has returned to the numbers. However, NmY still dominates and the proportion of NmY to the total number of invasive Nm isolates in Sweden was in congruence with previous years and the NmY represented 44% of the cases 2014, compared to 51% in 2013, 49% in 2012 and 51% in As previously shown, the emerging increase of serogroup Y in Sweden was due to a specific strain type, i.e. Y:P1.5-2,10-1,36-2:F4-1:ST23(cc23) (8, 13). This genosubtype P1.5-2,10-1,36-2 remained in 2014 the most prevalent genosubtype among all the invasive Nm isolates and represented 15/20 of the Nm serogroup Y isolates. No clusters or linked cases were reported in Sweden during Finally, it is of importance to follow (phenotypically and genetically) the changes within the meningococcal population circulating in the community, for example, in regards to future vaccine implementations and possible emergence of resistance to antimicrobials used in the prevention or treatment of invasive meningococcal disease.

4 Page 4 (8) Selected publications 1. Mölling P, Jacobsson S, Bäckman A, Olcén P. Direct and rapid identification and genogrouping of meningococci and pora amplication by LightCycler PCR. J Clin Microbiol 40: , Thulin Hedberg S, Olcén P, Fredlund H, Mölling P. Real-time PCR detection of five prevalent bacteria causing acute meningitis. APMIS 117: , Cavrini F, Liguori G, Andreoli A, Sambri V. Multiple nucleotide substitutions in the Neisseria meningitidis serogroup C ctra gene cause false-negative detection by real-time PCR. J Clin Microbiol 48: , Susanne Jacobsson. Doctoral dissertation. Characterization of Neisseria meningitidis from a virulence and immunogenic perspective that includes variations in novel vaccine antigens. Örebro Studies in Medicine 31, Örebro Sara Thulin Hedberg. Doctoral dissertation. Antibiotic susceptibility and resistance in Neisseria meningitidis phenotypic and genotypic characteristics. Örebro Studies in Medicine 38, Örebro Jacobsson S, Wedege E. A review of vaccines against group B meningococcal disease. European Infectious Disease 4:50-53, Thulin Hedberg S, Olcén P, Fredlund H, Unemo M. Antibiotic susceptibility of invasive Neisseria meningitidis isolates from 1995 to 2008 in Sweden the meningococcal population remains susceptible. Scand J Infect Dis 42:61-64, Thulin Hedberg S, Törös B, Fredlund H, Olcén P, Mölling P. Genetic characterisation of the emerging invasive Neisseria meningitidis serogroup Y in Sweden 2000 to Euro Surveill 16:1-7, Kelly A, Jacobsson S, Hussain S, Olcén P, Mölling P. Gene variability and degree of expression of vaccine candidate factor H binding protein in clinical isolates of Neisseria meningitidis. APMIS 121:56-63, Törös B, Hedberg ST, Jacobsson S, Fredlund H, Olcén P, Mölling P. Evaluation of molecular typing methods for identification of outbreak-associated Neisseria meningitidis isolates. APMIS 121: , Bröker M, Bukovski S, Culic D, Jacobsson S, Koliou M, Simões MJ, Skoczynska A, Toropainen M, Taha MK, Tzanakaki G. Meningococcal serogroup Y emergence in Europe: High importance in some European regions in Hum Vaccin Immunother 10: , Bianca Törös. Doctoral dissertation. Genome-based characterization of Neisseria meningitidis with focus on the emergent serogroup Y disease. Örebro Studies in Medicine 109, Örebro Törös B, Hedberg ST, Jacobsson S, Fredlund H, Olcén P, Mölling P. Surveillance of invasive Neisseria meningitidis with a serogroup Y update, Sweden 2010 to Euro Surveill 19:1-9, Report sent to: Public Health Agency of Sweden and its counterpart in the Nordic countries National Board of Health and Welfare EMGM The European Meningococcal Disease Society, with the Reference Laboratories in Europe ECDC WHO Euro Örebro Susanne Jacobsson, Hans Fredlund, Paula Mölling, Sara Thulin Hedberg, Bianca Törös, Martin Sundqvist, Magnus Unemo

5 Page 5 (8) Table I. Serogroup distribution for N. meningitidis isolates from 76 patients or carriers sent to the National Reference Laboratory for characterisation during One isolate per patient is presented. Serogroup CSF/blood Pharynx/airways incl. middle ear Urogenital B 6 4 a) 1 11 C Y b) 1 36 W E Total Non-groupable (ng) - 6 c) 3 9 Total a) 2 sputum b) 4 sputum, 1 middle ear c) 4 sputum, 1 BAL

6 Page 6 (8) Table II. Genosubtype pattern for all the invasive N. meningitidis isolates (n=45) sent to the National Reference Laboratory for characterisation during Displaying the three variable regions VR1, VR2 and VR3 of the pora gene. Genosubtype NmY NmB NmC NmW Nm29E Total P1.5-2,10-1, P1.5,2, P1.5-1,10-8, P1.5-1,10-1, P1.5,2-1, P1.5-1,2-2, P1.5-1,10-8,xx a) 1 1 P1.5-2,2-2, P1.5-2,10-12, P1.18-1,3, P1.22,9, P1.7,16, P1.7,16-29, P1.17-1,23-3, P1.19,13-1, P1.19-1,15-11, Total a) VR3 not typable

7 Page 7 (8) Tabell III. MIC range for all the invasive N. meningitidis isolates (n=45) sent to the National Reference Laboratory for characterisation during 2014 and clinical breakpoints within the SIR-system settled by the European Committee on Antimicrobial Susceptibility Testing/Nordic Committee on Antimicrobial Susceptibility Testing. Antibiotic MIC range (mg/l) S /R> a) Penicillin G /0.25 Cefotaxime < /0.12 Chloramphenicol /4 Ciprofloxacin /0.03 Rifampicin /0.25 Meropenem /0.25 a) S susceptible, R resistant. EUCAST/NordicAST breakpoints for Nm

8 Susanne Jacobsson Date Page: 8 (8) Table IV. Distribution of all N. meningitidis isolates sent for characterisation to the Reference Laboratory in Sweden from 2000 to Only one isolate per patient is included Total no. of Nm-isolates Nm from CSF/blood Nm from respiratory tract Nm from urogenital tract Other invasive Nm Nm från CSF/blood serogroup A B C Y W other ng