Ureaplasma Species: Role in Diseases of Prematurity

Abstract

SYNOPSISThere is accumulating epidemiologic and experimental evidence that intrauterine and/or postnatal infection with Ureaplasma species is a significant risk factor for adverse pregnancy outcomes and complications of extreme preterm birth such as BPD and intraventricular hemorrhage. In a cohort of very low birth weight infants, Ureaplasma spp. were detected by culture or PCR in respiratory secretions, blood, and/or CSF of almost half of the subjects, suggesting that this organism is the most common pathogen affecting this population. This review will summarize the evidence supporting the hypothesis that Ureaplasma-mediated inflammation in different compartments (intrauterine, lung, blood, and/or brain) during a common developmental window of vulnerability contributes to preterm labor and lung and brain injury. Appropriate methods for detecting these fastidious organisms and potential strategies to prevent or ameliorate the effects of Ureaplasma infection are discussed. KeywordsUreaplasma urealyticum; Ureaplasma parvum; intrauterine infection; prematurity; bronchopulmonary dysplasia; intraventricular hemorrhage Ureaplasma parvum (serotypes 1, 3, 6, and 14) and U. urealyticum (serotypes 2, 4, 5, 7-13) are closely related species of the Mollicutes class that are among the smallest free-living, selfreplicating cells [1][2][3] . All serovars lack cell walls, exhibit limited biosynthetic abilities, hydrolyze urea to generate ATP, and adhere to human mucosal surfaces 3 . U. parvum is the most common species isolated from clinical specimens 3,4 . Although Ureaplasma spp. are not typically considered pathogens in early onset neonatal sepsis, they have been implicated in complications of human pregnancy and neonatal outcomes. As observed by Volgmann et al. 5 in the title, of a recent review, Ureaplasma is either a "harmless commensal or underestimated enemy of human reproduction". This review will address this controversy and review evidence that the timing, duration, and intensity of the inflammatory response to Ureaplasma infection are major determinants of pregnancy and neonatal outcomes. EpidemiologyUreaplasma spp. are the most common bacteria implicated in human urogenital infections, including non-gonococcal urethritis in men and complications of pregnancy in women 5 . Ureaplasma spp. can be detected in vaginal flora in 40% of sexually inactive and 67% of © 2009 Elsevier Inc. All rights reserved.Mailing address: 29 S. Greene St., Rm GS110, Baltimore, MD 21201, Phone: 410-706-1913, Fax: 410-706-0404, rviscard@umaryland.edu. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain....

Current Status of the Mollicute (Mycoplasma) Lung Disease: Pathogenesis, Diagnostics, Treatment and Prevention

“…Although U. urealyticum and U. parvum are common commensals of the urogenital tract of humans, they are considered as important pathogens associated with infertility and nonwww.intechopen.com gonococcal urethritis in men, multiple obstetrical complications in women, and neonatal lung disease [Viscardi, 2010;Volgmann et al, 2005;. Genital ureaplasmas are natural residents of male urethra contaminating the semen during ejaculation.…”

“…Also, different specimens have been used, such as sputum, nasopharyngeal or pharyngeal swabs, brochoalveolar lavages or pleural fluid, and then it is difficult to compare these data. A comprehensive review about the use of NAATs for the detection of M. pneumoniae in clinical samples was done by Loens et al, 2003b, 2010, and by Ieven, 2010. …”

Detection and biovar discrimination of Ureaplasma urealyticum colonization in preterm neonates under ventilation and correlation with bronchopulmonary dysplasia

“…Data from 16srRNA sequencing led to classification of Ureaplasma serovars into two biovars; (Ureaplasma parvum, biovar 1, parvo) and (Ureaplasma urealyticum, biovar 2, T960) including a total of 14 serovars, biovar 1 included serotypes 1, 3, 6 and 14, and the remaining 10 serovars belonged to biovar 2 (Robertson et al, 2002). Characteristics of all serovars include lack of cell walls, limited biosynthetic abilities, small genome size, and mucosal association in the human host (Viscardi, 2010). The unique characteristic of Ureaplasma is their ability to hydrolyze urea to generate metabolic energy (Waites et al, , 2009.…”

“…Although U. urealyticum is a common commensal microorganism in the genital tract of sexually mature women (Abele-Horn et al, 1997a;Cunliffe et al, 1996), it is strongly associated with genitourinary syndromes and pregnancy complications such as chorioamnionitis, stillbirth, preterm delivery, neonatal morbidity and perinatal death (Abele-Horn et al, 2000;Yoon et al, 2001;Waites et al, 2005;Viscardi, 2010). They are the most common perinatally acquired pathogens in preterm infants (Viscardi, 2010).…”

“…They are the most common perinatally acquired pathogens in preterm infants (Viscardi, 2010). It appears that in-utero infection of the fetus is common, but neonates may also be colonized initially at the time of delivery (Waites et al, 2009).…”