Bliss Joseph M, Basavegowda Kumar P, Watson Wendy J, Sheikh Asad U, Ryan Rita M
Department of Pediatrics (Neonatology), Warren Alpert Medical School of Brown University, Women & Infants Hospital of Rhode Island, Providence, RI 02905, USA.
Pediatr Infect Dis J. 2008 Mar;27(3):231-5. doi: 10.1097/INF.0b013e31815bb69d.
Very low birth weight infants (VLBW, < or = 1500 g) are at increased risk for invasive disease caused by fungi, and colonization is an important risk factor. This study was designed to examine the effect of maternal flora on Candida colonization of VLBW infants.
Body site samples were collected within 24 hours of delivery from mothers who gave birth to VLBW infants, from their infants at birth, and then weekly for 12 weeks or until death or discharge. Yeast isolates were identified as Candida albicans by standard methods and typed by DNA fingerprinting using a C. albicans strain-specific DNA probe (CARE-2).
Sixty-six percent (50/76) of mothers were colonized with yeast and 51% (39/76) of their infants had a Candida species isolated at least once. Of 46 infants born to C. albicans-colonized mothers, 18 (39%) became colonized with C. albicans. Twenty-two percent (17/76) of the infants in the study were colonized with C. albicans by 1 week of age; 76% of these infants (13/17) were born to C. albicans-colonized mothers suggesting vertical transmission. DNA fingerprinting was performed on these 13 mother-infant pairs and 11 pairs demonstrated identical band patterns, confirming vertical transmission. However, of all infants colonized with C. albicans by the first week of age, just 65% (11/17) had a maternal source, and among all infants colonized at any time point, only 41% (11/27) became colonized by vertical transmission.
Both vertical and horizontal transmission contribute to Candida colonization of VLBW infants in the neonatal intensive care unit.
极低出生体重儿（VLBW，≤1500克）发生侵袭性真菌感染的风险增加，而定植是一个重要的危险因素。本研究旨在探讨母体菌群对VLBW婴儿念珠菌定植的影响。
对分娩VLBW婴儿的母亲在分娩后24小时内、其婴儿出生时采集身体部位样本，然后每周采集一次，共12周，或直至死亡或出院。采用标准方法将酵母分离株鉴定为白色念珠菌，并使用白色念珠菌菌株特异性DNA探针（CARE-2）通过DNA指纹图谱进行分型。
66%（50/76）的母亲有酵母定植，51%（39/76）的婴儿至少有一次分离出念珠菌属。在白色念珠菌定植母亲所生的46名婴儿中，18名（39%）被白色念珠菌定植。研究中22%（17/76）的婴儿在1周龄时被白色念珠菌定植；这些婴儿中有76%（13/17）的母亲为白色念珠菌定植，提示垂直传播。对这13对母婴进行了DNA指纹图谱分析，11对显示出相同的条带模式，证实了垂直传播。然而，在所有1周龄时被白色念珠菌定植的婴儿中，只有65%（11/17）有母体来源，在任何时间点定植的所有婴儿中，只有41%（11/27）是通过垂直传播定植的。
垂直传播和水平传播均导致新生儿重症监护病房中VLBW婴儿的念珠菌定植。
