[Whooping cough: a retrospective study of the cases diagnosed over a period of 15 years]

Our objective was to study the whooping cough cases diagnosed in a 15-year period in our hospital, referring to its clinical features, epidemiology and analytical findings.

A retrospective study based on 144 cases with a clinical diagnosis of whooping cough, from 1981 to 1995, was carried out. Special attention was paid to those cases with cultures positive for B. pertussis.

Nasopharyngeal specimens for culture were taken in 119 cases. This was not carried-out in those with previous antibiotic therapy. Cultures were positive for B. pertussis in 46 patients (38.7%). The age varied between 20 days and 30 months. Twenty-one were female. The initial symptoms were: paroxysmal cough in 44 (95.7%), cyanosis in 34 (73.9%), inspiratory whoop in 27 (58.7%), respiratory distress in 12 (26.1%) and post-tussive vomiting in 10 (21.7%). Thirty-nine children (84.8%) of this group had not received any pertussis vaccine, the rest had received just the first dose. It had been contacted by persons having cough in 19 patients (41.3%). Leukocytosis (mean: 19,818/mm3), lymphocytosis (mean: 13,047/mm3) and high platelet count (mean 459,522/mm3) were common findings.

Cultures were positive in 38.7% of the patients. There are similar findings by other authors. In this group, most of the children were unvaccinated, and less than 3 months of age. Typical symptoms of pertussis were observed in the majority of patients. In one forth of them respiratory distress was found, probably related to their young age. Vaccinated adults emerge as a contact group that should be studied.