Efficacy of rapid multiplex polymerase chain reaction for early diagnosis and treatment of pertussis

Abstract Background Pertussis, a highly infectious respiratory disease caused by Bordetella pertussis, causes airway inflammation and severe, persistent (lasting 2 weeks or more) characteristic whooping cough. In severe cases, complications such as atelectasis and bronchopneumonia may occur. Recently, the prevalence of pertussis has increased in South Korea due to reduced effect of the DTaP vaccination in infants as their age increased. Although culture is the gold standard test for diagnosis, polymerase chain reaction (PCR) method is most commonly used for diagnosis of pertussis due to the low sensitivity and long turnaround time of the culture method. Recently, a rapid multiplex PCR test has been introduced for comprehensive detection of respiratory pathogens (17 viruses and 3 bacteria), including Bordetella pertussis, with a turnaround time of 1 hour. This study aimed to investigate the efficacy of multiplex PCR for early diagnosis and treatment of pertussis. Methods We performed a retrospective study on patients with pertussis diagnosed from May 2017 to June 2019 at Yeungnam University Hospital. Nasopharyngeal swab specimens were tested using multiplex PCR. Medical records collected included data on age, sex, symptoms at the time of diagnosis, admission, hospitalization, isolation, vaccination history, past medical history, and accompanying diseases. Results A total of 27 patients were diagnosed with pertussis, nine (33.3%) of whom were men, with a median age of 48.9 years (3.3–82.2). Eleven (40.7%) had fever, 12 (44.4%) had dyspnea, 3 (11.1%) had paroxysmal cough, and 9 (33.3%) had inspiratory whooping. Seventeen (62.9%) and 24 (88.8%) patients had coughing for <8 days and ≤14 days, respectively. Median time from first symptom to diagnosis was 9.0 (1–31) days. Twenty-four patients (81.5%) were diagnosed within 2 weeks. All but one patient was prescribed macrolide antibiotics; all patients were isolated, with 22 (81.5%) requiring hospitalization. Three patients (11.1%) received ICU care for ventilation. All patients survived. Conclusion A rapid multiplex PCR test can ensure early diagnosis, isolation, and treatment of pertussis. Testing of patients with respiratory symptom with multiplex PCR can led to early diagnosis of pertussis, proper treatment, and may help in outbreak control.