[Pertussis syndrome: study of 74 cases].

Pertussis syndrome controversy induced us to study 74 hospitalized patients, with pertussis cough and Bordetella sp isolation in 29, other bacteria in 24 and viruses in 21. The most frequently isolated bacteria in the patients with negative culture for bordetella were Haemophilus influenzae, Streptococcus pneumoniae and Branhamella catarrhalis. The viruses with highest incidence were respiratory syncitial viruses. The negative culture for bordetella, the lack of antibiotherapy previous to obtention of the sample (29/45 cases), the clinical differences and their different seasonal distribution in relation to the patients with positive culture for bordetella, permit us to suppose that the bacteria/viruses isolated could be the etiologic agents of pertussis syndrome. Although Bordetella sp occupies an important place in the pertussis cough etiology, it is advisable to investigate the presence of viruses and other bacteria in these patients. However the difficulties to isolate bordetella implies the necessity of performing adequate isolation techniques and to study larger numbers of patients including control groups.