Background/purpose: Exclusion criteria for enema reduction of intussusception are still a matter of debate. The current study aimed to search for risk factors and to design and evaluate a predictive model of air enema failure.
Methods: The design was a cross-sectional study. The study was conducted at a tertiary university hospital. The participants were 164 children (mean [SD] age of 11.6 [10.7] months) with intestinal intussusception. The intervention done was pneumatic reduction only contraindicated in case of peritonitis and/or sepsis. For main outcome measures, logistic regression analysis was used to estimate the contribution of clinical parameters (age, sex, weight, clinical evolution, temperature, rectal bleeding, white blood cell count, and neutrophils) to predict the risk of enema failure. To evaluate the discriminating power of the model, a receiver operating characteristic curve was constructed, and the effectiveness at different cutoffs was calculated.
Results: Overall efficacy was 85%; manual reduction was performed in 12 (7.3%) cases, and there were 9 (6.5%) recurrences. Multivariable analysis adjusted for age and sex revealed that delayed diagnosis (evolution >24 hours) and raised neutrophils (%) were associated with failure: odds ratio of 11.52 (95% CI, 3.73-35.54) and 1.06 (95% CI, 1.02-1.11), respectively. The area under the receiver operating characteristic curve was 0.826 (95% CI, 0.740-0.912). At the best cutoff (0.15), the positive predictive value was 35% and the negative 93%. At the cutoff of 0.50, the positive predictive value was 70% and the negative 87%; the sensitivity was 29%.
Conclusions: The efficacy and safety of pneumatic reduction in childhood intussusception was confirmed. Delayed diagnosis and neutrophils significantly predict outcome. Despite consistent high negative predictive values, the model has low effectiveness in predicting enema failure and may not be clinically relevant; there is no rationale for stricter exclusion criteria.