Diagnostic value of symptoms and laboratory data for pertussis in adolescent and adult patients

Abstract

BackgroundSeveral symptoms are classically thought to be suggestive of pertussis in children, but the diagnostic value of these symptoms in adolescent and adult patients is unclear. We evaluated the accuracy of the clinical findings for the early presumptive diagnosis of pertussis in adolescent and adult patients. Furthermore, we measured fractional exhaled nitric oxide (FeNO) with regard to whether we could distinguish eosinophilic inflammation of the airway and pertussis. FeNO is not expected to be associated with pertussis.MethodsWe compared 183 cases with laboratory-confirmed pertussis using serology and polymerase chain reaction and 1,132 cases without laboratory-confirmed pertussis.ResultsAmong pertussis patients, paroxysmal cough was common with 90% sensitivity, but the specificity was low (25%). Posttussive vomiting and whoop were less common (sensitivity 25% and 19%, respectively), but both showed greater specificity for pertussis (80% and 86%, respectively). Posttussive gagging was observed with intermediate frequency and provided greater specificity (49% and 77%, respectively). Pertussis cases were most frequent between May and August with a peak in June. The mean FeNO value for the pertussis patients was 18.2 ± 9.2 ppb, which was significantly lower than that in asthma patients (56.9 ± 20.3 ppb, p <0.001). The most useful definition was posttussive vomiting and/or gagging, and a plus normal FeNO value, which had a sensitivity of 72% and a specificity of 70%.ConclusionsClinical symptoms and laboratory data are of limited value in making the diagnosis of pertussis, and it was clinically difficult to differentiate adolescent and adult patients with or without pertussis. However, pertussis should be considered if patients have posttussive vomiting and/or gagging and a normal FeNO concentration.

Clinical Manifestations of Children with Microbiologically Confirmed Pertussis Infection and Antimicrobial Susceptibility of Isolated Strains in a Regional Hospital in Japan, 2008^|^ndash;2012

“…Wood et al have reported that young infants may initially present with apnea alone (8). A previous study reported the following frequency of symptoms, which is similar to the results of our study: paroxysmal cough, 100z; prolonged cough over 14 days, 43z; inspiratory whoop, 39z; posttussive vomiting, 25z; and apnea, 7z (9). Clinical features, excluding apnea, were observed in unvaccinated and previously vaccinated patients.…”

Laboratory Diagnosis of Pertussis

“…Clinical case definitions vary by country and/or institution (28,29). The specificity of case definitions is negatively influenced by the time between infection and diagnosis, by previous vaccination or infection, and by increasing age of patients (30). Furthermore, the sensitivity of clinical diagnosis is low for adolescents and adults, due to the mitigated presentation of the disease.…”

Perfil clínico de pacientes com suspeita de coqueluche atendidos em hospital pediátrico e dificuldades operacionais na confirmação laboratorial

“…18,19 O IPPMG não dispõe de material para identificação da B. pertussis. Quando há suspeita e notificação do agravo, procede-se a coleta de material e envio para o laboratório-referência de saúde pú-blica do Rio de Janeiro (Lacen-RJ), o qual disponibiliza o swab e o meio de cultura para coleta.…”

“…Estudos em São Paulo têm mostrado a baixa positividade do exame realizado pela técnica de cultura em relação à técnica de RT-PCR, 22,23 e em outros países a sorologia é apontada como método de maior positividade e pode ser de única amostra de soro no período de duas a oito semanas após o início da tosse, quando o nível de anticorpos atinge seu máximo. 6,24,25 Apesar do não isola mento da B. pertussis, na amostra estudada, sintomas descritos em outros estudos como fortemente associados ao diagnóstico de coqueluche 18,19,26 estavam presentes em nossos pacientes, como tosse persistente, paroxística, cianose, temperatura abaixo de 38 °C e achados laboratoriais inespecíficos, como contagem de linfócitos maior ou igual a 10.000/mm 3 e de leucóci-tos de 20.000/mm 3 ou mais, também descritos na literatura como associados ao diagnóstico de coqueluche confirmada por testes específicos. 27 Neste estudo sete pacientes (11%) evoluíram para óbito.…”