A PRIMATE MODEL OF UREAPLASMA-UREALYTICUM INFECTION IN THE PREMATURE-INFANT WITH HYALINE-MEMBRANE DISEASE

Cultures positive for Ureaplasma urealyticum in babies weighing <1000 g have been associated with both chronic lung disease (CLD) and death, but no definite causality has been established. To further investigat e the role of the organism in CLD, we colonized premature baboons with U. urealyticum and compared resulting pathology with that in uninocul ated control animals. Using an established model of prematurity, the 1 40-day-gestation baboon, three animals were colonized with U. urealyti cum via endotracheal tube. All had hyaline membrane disease, indisting uishable from disease in human infants, and U. urealyticum infection. Samples obtained from nasopharynx, trachea, pleural fluid, and, at nec ropsy, lung tissue produced positive cultures. Culture of blood from o ne animal yielded U. urealyticum. On pathologic examination, after 6 d ays of ventilation, all three of the infected animals had the specific pathologic finding of bronchiolitis with epithelial ulceration not se en in four uninfected control animals. Thus, U. urealyticum is capable of causing a pathologically recognizable pulmonary lesion in prematur e primates with hyaline membrane disease.