Mycoplasma pneumoniae: acute illness, antibiotics, and subsequent pulmonary function.

One hundred and eight children presenting with Mycoplasma pneumoniae infection were assessed during the acute illness and followed for three years. The incidence of wheezing with the acute infection (40%) was greater than expected in a normal childhood population. The initial illness precipitated wheezing for the first time in some subjects but others wheezed only with the acute illness. In non-asthmatic subjects significant bronchodilator responsiveness was present one month after infection. Children given erythromycin during the first seven days of their illness had a significantly shorter fever duration compared with those treated inappropriately. No significant effects of treatment were noted on pulmonary function three years later but non-asthmatic children had abnormal mean forced expiratory volume in one second and forced expiratory flow after 50% of the expired vital capacity compared with 64 healthy controls. These findings indicate impaired function three years after initial infection.

Transitory depression of immune function following Mycoplasma pneumoniae infection in children.

A broad array of immunological tests was performed in children with serologically confirmed Mycoplasma pneumoniae infection. In a group of 21 children studied 0 to 6 wk after onset of of illness, neutrophil chemotaxis was 1.46 +/- 0.43 mm/3 hr (mean +/- S.D.) in patients compared to 1.79 +/- 0.28 mm/3 hr in controls (P less than 0.05). In a subgroup of seven children studied 0 to 2 wk after onset of 2,635 cpm in patients compared to 26,454 +/- 3,345 in controls for phytohaemagglutinin (P less than 0.02) and 5,321 +/- 535 in patients less than 0.02). There was, however, no impairment in response to soluble concanavalin A: 18,715 +/- 1,446 in patients compared to 25,193 +/- 2,564 in controls (P greater than 0.1). Follow-up studies on five of these seven children showed that lymphocyte proliferative responses to phytohaemagglutinin and pokeweed mitogen of all five children returned to normal values some weeks later. In another group of 28 children studied 13 to 18 wk after onset of illness, four had subnormal IgG values. Of the three children available for followup studies, all had normal values for serum IgG 2 to 5 months later.