title: Underestimation of Invasive Meningococcal Disease in Italy.
abstract: Knowing the incidence of invasive meningococcal disease (IMD) is essential for planning appropriate vaccination policies. However, IMD may be underestimated because of misdiagnosis or insufficiently sensitive laboratory methods. Using a national molecular surveillance register, we assessed the number of cases misdiagnosed and diagnoses obtained postmortem with real-time PCR (rPCR), and we compared sensitivity of rPCR versus culture-based testing. A total of 222 IMD cases were identified: 11 (42%) of 26 fatal cases had been misdiagnosed or undiagnosed and were reclassified as IMD after rPCR showed meningococcal DNA in all available specimens taken postmortem. Of the samples tested with both rPCR and culture, 58% were diagnosed by using rPCR alone. The underestimation factor associated with the use of culture alone was 3.28. In countries such as Italy, where rPCR is in limited use, IMD incidence may be largely underestimated; thus, assessments of benefits of meningococcal vaccination may be prone to error.
authors.forename: Chiara
authors.initials: C
authors.lastname: Azzari
authors.forename: Francesco
authors.initials: F
authors.lastname: Nieddu
authors.forename: Maria
authors.initials: M
authors.lastname: Moriondo
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Indolfi
authors.forename: Clementina
authors.initials: C
authors.lastname: Canessa
authors.forename: Silvia
authors.initials: S
authors.lastname: Ricci
authors.forename: Leila
authors.initials: L
authors.lastname: Bianchi
authors.forename: Daniele
authors.initials: D
authors.lastname: Serranti
authors.forename: Giovanni Maria
authors.initials: GM
authors.lastname: Poggi
authors.forename: Massimo
authors.initials: M
authors.lastname: Resti
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007558:Italy / Q000453:epidemiology; D008297:Male; D008589:Meningococcal Infections / Q000175:diagnosis / Q000453:epidemiology*; D022401:Meningococcal Vaccines; D009345:Neisseria meningitidis; D060888:Real-Time Polymerase Chain Reaction; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D022401:Meningococcal Vaccines
keywords: Italy; Neisseria meningitidis; PCR; bacteria; bacterial meningitis; invasive meningococcal disease; misdiagnosis; underestimation; underreporting