Bacterial Diversity Of The Gastric Content Of Preterm Infants During Their NICU Stay. Gastric microbiota

Gastric microbiota, because of its drastic conditions was classically the missing point in the study of the gastrointestinal tract. Despite recent studies described a complex gastric microbiota in adults, little is known concerning neonates. Thirteen preterms infants with a mean gestational age of 28 weeks and a birth weight of 1192 g provide gastric content samples for its microbiological description using culture dependent and independent techniques. Bacterial growth was detected in the 79% of the gastric content samples. Dominant species found by culture techniques were Staphylococcus epidermidis, Enterococcus faecalisand Serratia marcescens. Clinically relevant isolates were typed by MLST analysis and revealed the presence of strains belonged to high risk clonal complexes in the gastric microbiota of preterms. Molecular analysis unveiled a phylogenetically diverse microbiota. The same dominant genera conforming gastric contents were found in feeding samples. In that way, minority genera such as Mycoplasma, Balneimonas, Aerococcus, Raoultella,Caulobacter; Shewanella and Facklamia were described as the autochthonous microbiota of studied infants. Both, culture and molecular techniques remarked Proteobacteria as the predominant phyla in gastric content samples pointing to hospital environment as an important factor modulating preterm microbiota at least during their hospital stay. Further work is required to better understand gastric colonization process and establish whether this information can be used to improve infant outcomes.