Breath hydrogen excretion as a screening test for the early diagnosis of necrotizing enterocolitis
H. W. Cheu, D. R. Brown and M. I. Rowe
Department of Surgery, Children's Hospital of Pittsburgh, PA.
We measured breath H2 excretion in 122 neonates from birth to 1 month of
age. The patients weighed less than 2000 g at birth and thus were at risk
for developing necrotizing enterocolitis (NEC). Hydrogen excretion was
normalized for the quality of the expired air by dividing by the carbon
dioxide pressure of the gas sample. The mean (+/- SD) peak H2/CO2 ratio was
significantly different between the seven patients who subsequently
developed NEC (9.4 +/- 2.7 ppm/mm Hg) and the 115 patients who did not (5.0
+/- 3.5 ppm/mm Hg). The prevalence of NEC was 5.7% in the present study.
Defining a positive test as one with a ratio value of greater than or equal
to 8.0 ppm/mm Hg, the resulting screening test had a sensitivity of 86% and
a specificity of 90%. The screening test yielded a 33% predictive value of
a positive test and a 99% predictive value of a negative test. High H2
excretion occurred eight to 28 hours before the earliest clinical signs of
NEC. Breath H2 excretion is a simple noninvasive test that may be useful in
the management of the premature neonate at risk for the development of NEC.
