RESUMEN
A prospective survey was undertaken in patients hospitalized from january 1976 to april 1978 with clinical, biological and radiological features of atypical pneumonia.In all patients samples were taken early and 15 days after the on set of the disease to detect specific serum antibodies to influenza A and B viruses, parainfluenza type I, II and III, adenoviruses, respiratory syncitial virus, Micoplasma pneumoniae and Chlamydia psittaci. A fourfold rise in antibodies was observed in 23,7 % of patients (M. pneumoniae 43 %, influenza A virus 28,5 % and C. psittaci 14 %). Taking into account titers equal or higher than 1/64, a specific agent can be recognized in 50 % of 59 cases.Because of those poor results, the delay to obtain them and their cost, the interest of such a laboratory study is questionable.
