Original Article
Prognostic value of abdominal sonography in necrotizing enterocolitis of premature infants born before 33 weeks gestational age

https://doi.org/10.1016/j.jpedsurg.2013.11.057Get rights and content

Abstract

Objective

The purpose of this study was to assess the prognostic value of abdominal sonography in necrotizing enterocolitis (NEC) in preterm infants with a gestational age less than 33 weeks of gestation, using surgery and/or death as the primary outcome and stenosis as the secondary outcome.

Methods

A retrospective study of 95 premature infants (mean gestational age: 28.6 weeks), presenting with NEC between January 2009 and November 2011 and who underwent plain abdominal radiography and sonography, was performed. In uni- and multivariate analyses, radiographic and sonographic findings were correlated with complications (‘surgery and/or death’ and ‘stenosis’).

Results

Sonographic findings of free intraperitoneal air (odd ratio [OR] = 8.0; IC, 1.4–44.2), free abdominal fluid (OR 3.5; IC 1.3–9.4), portal venous gas (OR 3.9; IC, 1.2–12.9), and bowel wall thickening (OR 2.8; IC,1.1–7.2) were significantly associated with surgery and/or death. Intramural gas was significantly correlated (OR = 11.8; IC, 1.5–95.8) with intestinal stenosis following NEC. None of the radiographic findings were associated with complications.

Conclusion

Abdominal sonography is a reliable tool for the prognostic assessment of NEC in preterm infants.

Section snippets

Patients and methods

This was a single-center, retrospective study conducted in a Level 3 university maternity unit.

Description of the study population

In total, 442 premature infants of less than 33 weeks gestational age were born between January 1, 2009 and November 30, 2011, of whom 123 (27.8%) presented with NEC symptoms (Fig. 1).

For the 28 infants excluded from analysis, intrauterine growth retardation was more common (46.4% vs. 20.7%, p = 0.007) and birth weight lower (1037 ± 299 vs. 1175 ± 309, p = 0.038) than for the 95 infants included in the analysis. As to NEC stages, they were less than or equal to stage 1B of Bell’s classification. All of

Discussion

NEC is a common complication of prematurity, as nearly 90% of cases involve preterm infants (< 37 weeks gestational age). NEC’s incidence and the associated morbidity and mortality remain unchanged over time due to the birth of increasingly immature infants. In our NICU, the rate of Stage ≥ 2 NEC [5] in infants of less than 33 weeks gestational age (7.4%) was similar to the data reported in the literature [2], [25].

The usefulness of ultrasonography in NEC diagnosis has been known since 1984 [12].

Conclusion

Ultrasonography is a useful tool for assessing the prognosis of NEC in preterm infants and allows for detecting signs predictive of adverse outcome. Sonographic intramural gas at the time of the acute episode was associated with a high risk of stenosis. Furthermore, abdominal fluid or free air, portal venous gas, and parietal thickening detected on abdominal ultrasound were also associated with an adverse evolution (surgery and/or death). Physicians should consider the use of abdominal

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    Conflict of interest: We have no conflict of interest in relation to this study.

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