Implementation and Assessment of the Use of Real-Time PCR in Routine Diagnosis for Bordetella pertussis Detection in Brazil

Abstract

Background: Bordetella pertussis is the causative agent of pertussis. In Brazil, laboratory diagnosis of pertussis is based on the culture. In 2010, was standardized the Real-Time PCR TaqMan® in routine diagnosis. Objectives: The aim of this study was to evaluate the impact achieved with the introduction of RT-PCR for the routine diagnosis of pertussis and to compare with the results obtained from culture. Patients and Methods: 4,697 samples of nasopharyngeal secretions collected from suspected pertussis cases and/or contacts were analyzed for RT-PCR and culture, from January 2008 until the end of December 2011. Results: According to the results obtained from the samples 6.9% were culture/RT-PCR positive, 14.8% were positive only for RT-PCR and 0.2% only for culture. Negative samples for both techniques was 3,622 (77.1%) and 1.0% were inconclusive for RT-PCR. Conclusions:The implementation of RT-PCR in routine diagnosis resulted in an increase in laboratory confirmation by almost three times. The RT-PCR assay does not intend to replace the culture technique, but to promote an improvement in the diagnosis of pertussis.

Laboratory Diagnosis of Pertussis

“…Thus, when PCR is compared to culture, the sensitivity of PCR is 100%. The sensitivity of culture compared to PCR ranges from 26% to 85% (93,150,(265)(266)(267)(268). It has been shown that the sensitivity of culture with regard to PCR sensitivity decreases with an increasing duration of disease, and thus shows a steeper decline than that of PCR (267).…”

"Do we Need to Investigate Respiratory Virus in Hospitalized Infants with Suspected Pertussis?"

“…Following a standardized protocol, we collated demographic, clinical, laboratory, and outcome data. According to the service routine, all these patients had nasal swab for BP identification (culture techniques and polymerase chain reaction (PCR), standardized at the Adolfo Lutz Institute [5]) and nasopharyngeal secretions for RV identification (indirect immunofluorescence assay) collected at admission. The patients were divided into two groups, with single agent detection, for comparison: the group with pertussis (BP) and the group with respiratory virus (RV).…”

Epidemiology of pertussis among adolescents, adults, and older adults in selected countries of Latin American: a systematic review

“…Nine of them [25][26][27][28][29][30][31][32][33] included data from the national surveillance system SINAN (Sistema de Informação de Agravos de Notificação [System for Notifiable Diseases]); two used convenience samples of household contacts 34 or healthcare workers; 35 each used data from one 36 or ten 37 hospital clinics; and one 12 study was a population-based study. We retrieved 11 crosssectional studies, 25,26,28,29,[31][32][33][34][35]37,38 one case-control study, 13 one case series, 36 and one literature review 14 (Table 1). The pertussis-confirmed cases in the in-scope population reported by all included studies, ranged from 5.2% to 14.0% (Table 1).…”

“…3,10 Despite the well-accepted definition of cases 1 underreporting and misdiagnosis, particularly among adolescents and adults, is a problem worldwide. [12][13][14] Adolescents and adults may present atypical symptoms limited to mild or prolonged non-distinctive cough, but they may also suffer severe symptoms such as sleep disturbance, pharyngeal symptoms, weight loss, sneezing attacks, sinus pain, sweating, and headaches. 2 Still, data on the epidemiology and clinical characteristics of the disease in adolescent and adult populations are limited.…”

“…15,16 Furthermore, findings suggest that pertussis incidence in adults aged >50 years old has been increasing over the past years 3 but it remains significantly underestimated. 14 We aimed to systematically review the epidemiology of pertussis disease in adolescents, adults, and older adults over the past decade in selected Latin American countries.…”