[Infection by Mycoplasma pneumoniae. Epidemiologic investigation and statistical clinical study of 122 children admitted to the Institute of Pediatrics of the University of Florence during the period 1 January 1977 to 31 December 1983].

We carried out an epidemiologic research about M. Pneumoniae infection from 1977 to 1983: determination of CF antibodies has been performed by the Bacteriology and Virology Laboratory (Prof. Lamanna, USL 10/D, Florence). Serum samples were collected by the laboratory itself and by hospitals and university departments of Florence and neighbouring communes. Our research confirms cyclic behaviour of M. Pneumoniae infection: we could follow up a 3 years long epidemic after a previous 2 years long endemic disease. We found a major sera-positive rate for M. Pneumoniae in children than in adults. In the same period we carried out a clinical-statistical study on 122 children (80 males and 42 females) admitted to the Pediatric Institute "A. Meyer" in Florence because of an infection due to M. Pneumoniae. The most affected age range sems to be included between 5 and 10 years. Pneumonia is the commonest clinical feature of M. Pneumoniae infection (85.2%): furthermore, we must point out some cases in 0-2 years-old subjects. In our patients, clinical features, X-ray findings and laboratory tests strictly agree with those reported by other authors. We treated all our patients with erythromycin: in three weeks we obtained thee normalization of clinical patterns and X-ray findings in all cases.