Late-onset volvulus without malrotation in extremely preterm infants - a case–control-study

BACKGROUND Volvulus without malrotation in preterm infants is a rare but potentially life-threatening event of unknown aetiology. Confusion with necrotising enterocolitis may delay surgical intervention thereby aggravating morbidity and mortality. We aimed at elucidating potential risk factors for, and characteristic clinical signs of, volvulus without malrotation in preterm infants. METHODS Retrospective, single-centre case-control study (2007-2011). For every index patient, five infants of similar gestational age, birth weight and birth year were evaluated. Additionally, all 9 cases of necrotising enterocolitis occurring during the above period were evaluated. Data are presented as median (interquartile range). RESULTS Five extremely premature infants suffering from volvulus without malrotation were identified (gestational age at birth 24.4 (23.6-25.5) weeks, birth weight 480 (370-530) g). All were small for gestational age and female; three out of five died. Volvulus occurred several weeks after birth, whereas necrotising enterocolitis occurred significantly earlier. Beyond that, no striking differences in clinical or laboratory presentation of volvulus without malrotation and necrotising enterocolitis were found. Infants with volvulus had significantly more frequent manipulations with rectal tubes for flatulence, but there were no differences in the frequency of enemas, abdominal massage or defecation. In infants with volvulus, nasal high-frequency oscillation was used more frequently for respiratory support, and PEEP-level tended to be higher. CONCLUSIONS In extremely premature infants volvulus without malrotation represents a life-threatening event that occurs typically several weeks after birth with an acute abdomen and seems to affect predominantly girls. Infants requiring intensive non-invasive respiratory support might be at highest risk.