Pertussis in Missouri: evaluation of nasopharyngeal culture, direct fluorescent antibody testing, and clinical case definitions in the diagnosis of pertussis

Clin Infect Dis. 1993 Feb;16(2):276-85. doi: 10.1093/clind/16.2.276.


No diagnostic test for pertussis in routine use in the United States has both high sensitivity and high specificity. During a statewide increase in the incidence of pertussis in Missouri, we studied the clinical features of 153 patients with suspected pertussis in the Greater St. Louis area from whom a specimen for pertussis culture had been taken between 15 May and 19 September 1989. In this cross-sectional study, nasopharyngeal cultures were more likely to be positive for persons whose specimens were collected < 21 days after cough onset (adjusted rate ratio [RRa] and 95% confidence interval = 3.4; 1.5-8.0) and who were not receiving erythromycin/sulfamethoxazole prior to the culture [RRa = 5.8; 0.8-40.6], who had received fewer than three prior doses of pertussis vaccine [RRa = 1.8; 0.8-4.2], and whose specimen was in transit to the laboratory for < 4 days [RRa = 2.0; 0.8-5.5]. Among children < 5 years of age, spasmodic cough plus a lymphocytosis of > 10,000/mm3 was the acute symptom complex associated with the highest predictive value for a positive culture result (67%). Cough for > or = 14 days plus whoop was sensitive (81%) and specific (58%) for identifying children with culture-confirmed pertussis. Direct fluorescent antibody staining performed well as a screening test for pertussis but requires substantial commitment of personnel and resources. In the absence of a positive culture result, clinical case definitions should be used for decision making (e.g., initiation of antimicrobial therapy and routine case reporting).

MeSH terms

  • Adolescent
  • Bacteriological Techniques / statistics & numerical data
  • Bordetella pertussis / immunology
  • Bordetella pertussis / isolation & purification
  • Child
  • Child, Preschool
  • Cross-Sectional Studies
  • Diagnostic Errors
  • Epidemiologic Methods
  • Evaluation Studies as Topic
  • Female
  • Fluorescent Antibody Technique / statistics & numerical data
  • Humans
  • Infant
  • Male
  • Missouri / epidemiology
  • Nasopharynx / microbiology
  • Sensitivity and Specificity
  • Whooping Cough / diagnosis*
  • Whooping Cough / epidemiology