Pertussis (Whooping Cough): Test and Diagnosis

2nd order laboratory parameters – depending on the results of the history, physical examination, etc. – for differential diagnostic clarification

  • Small blood count
  • Differential blood count
  • Bacteriology: nasopharyngeal swab, (possibly nasal or throat swab) [cultural detection is reliable only within two weeks].
  • Pathogen detection by PCR (dry swab; material: tracheal secretion, bronchoalveolar lavage (BAL; method of sample collection used in bronchoscopy (lung endoscopy)); nasopharyngeal swab) [more sensitive than cultural pathogen detection; can detect the infection up to 4 weeks, if necessary].
  • Serology: AK against Bordetella pertussis and parapertussis [only suitable for the late phase of disease; pertussis IgM antibodies are not informative; a high IgG antibody titer or a significant IgG antibody titer increase confirms the clinical diagnosis; IgA antibodies have a low sensitivity/percentage of ill patients in whom the disease is detected by the use of the test, i.e., a positive test result occurs].