Role of Chlamydia pneumoniae in acute chest syndrome of sickle cell disease.

Children with sickle cell disease and acute chest syndrome were investigated for infection with Chlamydia pneumoniae and Mycoplasma pneumoniae. Of 30 patients who had 32 episodes of acute chest syndrome, four (13%) had C. pneumoniae isolated from the nasopharynx; two of these also had serologic evidence of acute infection, and one had positive nasopharyngeal isolates on two subsequent occasions during the course of 1 year with stable, elevated titers of anti-C. pneumoniae IgG, suggesting chronic infection. Two patients with negative cultures had serologic evidence of infection with C. pneumoniae. None of 32 cultures for M. pneumoniae were positive, and although anti-M. pneumoniae IgM developed in two patients, one of these patients had evidence of C. pneumoniae infection (positive culture and seroconversion). We conclude that C. pneumoniae infection is prevalent in our sickle cell population with acute chest syndrome. Until further studies clarify the pathophysiologic significance of C. pneumoniae infection, we believe that early inclusion of erythromycin as antimicrobial therapy for acute chest syndrome seems reasonable.