Detection of Ureaplasma urealyticum in Endotracheal Tube Aspirates from Neonates by PCR

Abstract

A PCR-based test was optimized for the detection ofUreaplasma urealyticum from neonatal respiratory specimens, with primers directed against the multiple-banded antigen gene (L. J. Teng, X. Zheng, J. I. Glass, H. Watson, J. Tsai, and G. H. Cassell, J. Clin. Microbiol. 32:1464–1469, 1994). Endotracheal tube aspirates (225) from 103 low-birth-weight neonates (<1,250 g) were taken, when possible, at days 0, 4, and 14 after birth and examined by culture and by PCR. Of 77 specimens positive by either method, 73 were detected by PCR and 60 were detected by culture. Overall, 36% of the neonates were positive for U. urealyticum by either method. Of 16 patients with PCR-positive–culture-negative results, 13 had positive cultures at another sampling point, and one additional patient had a twin with positive cultures. Of 11 patients with day 0 specimens positive by PCR alone, 9 subsequently became culture positive, demonstrating the utility of this test in early detection. Multiple serovars were present in over 50% of positive specimens, with serovars 3 and 14 in combination being most prevalent. The amplicon size generated from the specimen by PCR correctly predicted the biovars isolated in over 85% of positive specimens. Thus, this PCR test was valuable in allowing early detection of U. urealyticum in neonatal respiratory specimens, as well as in providing biovar information.

Detection of Ureaplasma DNA in Endotracheal Samples Is Associated With Bronchopulmonary Dysplasia After Adjustment for Multiple Risk Factors

“…Another potential explanation for the controversy may be the modality used to detect Ureaplasma sp. Relying on a single clinical culture may misclassify up to 40% of positive patients as negative (13,17,37,43). PCR is more sensitive than culture and can detect both low numbers of organisms and dead organisms (36,37,44).…”

Lung Pathology in Premature Infants with Ureaplasma urealyticum Infection

“…Culture alone may significantly underestimate the colonization rate and undetected positive infants may have been included with negative infants in some studies. Detection of respiratory tract colonization with U. urealyticum by polymerase chain reaction (PCR) suggests that colonization in VLBW infants is higher (35%-46%) [19,21,22] than previously reported for culture-based studies (20%) [13]. Although all colonization with U. urealyticum detected by culture is also detected by PCR, additional infants who are culture negative are PCR positive [19,21,22].…”

Colonization of paediatric lower respiratory tract with genital Mycoplasma species

“…It is not clear what role, if any, the urogenital Mycoplasmas and Ureaplasma play in acute or chronic 29 In recent studies the urogenital Mycoplasmas have been associated with respiratory distress in newborns 30 and neonatal meningitis. 31 The Ureaplasmas have been linked with preterm labour, 32 intrauterine lung disease 33 and neonatal pneumonia. 34 The data resulting from this study suggest that a negative M. pneumoniae PCR test does not always mean that Mycoplasma is absent.…”