Ultrasound Shows High Accuracy for Paediatric Intestinal Malrotation and Volvulus

Ultrasound can diagnose intestinal malrotation and its most dangerous complication, midgut volvulus, with high accuracy in children already suspected of having the condition, according to a retrospective study conducted at the Children's Hospital of Fudan University in Shanghai. The research, published in Frontiers in Pediatrics, analysed 143 children with high clinical suspicion of intestinal malrotation who were evaluated between January 2017 and June 2024. The authors present ultrasonography as a nonradiation-based alternative to the upper gastrointestinal series, which has long served as the traditional diagnostic tool for this condition.

The Shanghai team applied a standardized ultrasound assessment to every child in the cohort, focusing on three markers. The first was the relationship between the superior mesenteric artery and the superior mesenteric vein. The second was whether the third portion of the duodenum, known as D3, occupied its retroperitoneal position.

The third was the presence of the so-called whirlpool sign. Surgical findings or clinical follow-up served as the gold standard against which the ultrasound results were judged, allowing the team to calculate sensitivity, specificity, and accuracy for diagnosing malrotation, and for the whirlpool sign as a marker of midgut volvulus. Among the 143 suspected cases, 110 children, or 76.9 percent, were confirmed to have intestinal malrotation.

Ultrasound achieved both a sensitivity and a specificity of 90.9 percent for diagnosing the condition, meaning it correctly identified roughly nine in ten children who had malrotation and correctly cleared roughly nine in ten of those who did not. Subgroup analysis indicated numerically higher diagnostic sensitivity and specificity in neonates, a trend the authors report as a numerical observation within the cohort rather than a definitive conclusion. The whirlpool sign proved especially powerful for detecting midgut volvulus.

Of the 110 children with surgically confirmed malrotation, 78, or 70.9 percent, were also complicated by volvulus. Within this malrotation-confirmed subgroup, the whirlpool sign demonstrated a sensitivity of 93.6 percent, correctly identifying 73 of the 78 children with volvulus, and a specificity of 93.8 percent, correctly excluding volvulus in 30 of the 32 children without it, a result that was statistically significant. Because volvulus is a surgical emergency, the authors describe the whirlpool sign as a critical indicator for emergency surgical decision-making.

The study's analysis of diagnostic errors offers a cautionary counterpoint. Thirteen cases were discordant with the gold standard: three false positives and ten false negatives. The false positives occurred in children with non-malrotation conditions such as mesenteric lymphadenitis.

Every false negative, meanwhile, was ultimately confirmed surgically because clinicians maintained a high index of suspicion despite the negative scan. This pattern underlines the study's central caveat: a negative ultrasound does not completely rule out intestinal malrotation and must be interpreted alongside the overall clinical picture. The single-centre, retrospective design shapes how these findings should be read.

All children in the cohort were pre-selected for high clinical suspicion, so the reported sensitivity and specificity apply to that enriched population rather than to children evaluated routinely for abdominal pain in general settings. The whirlpool sign's performance was also measured only within children already confirmed to have malrotation, not as a standalone screening test. Even with those limitations, the results carry weight for paediatric surgery and emergency medicine.

The authors' conclusion is measured: ultrasound exhibits high diagnostic efficacy for both intestinal malrotation and midgut volvulus in this cohort, but clinical judgement remains indispensable, because the scan that comes back negative in a child with persistent suspicion is a reason to keep investigating, not a reason to stop.

Subject of Research: Diagnostic accuracy of ultrasound for paediatric intestinal malrotation and midgut volvulus

Article Title: Ultrasound for diagnosing paediatric intestinal malrotation and midgut volvulus: a retrospective study in a single-centre high-suspicion cohort

Article References: Lin, F., Wu, W., Zhang, H., Gao, Y., Zhang, G., Chang, T., Gao, S., Sun, S., & Sun, Y. (2026). Ultrasound for Diagnosing Paediatric Intestinal Malrotation and Midgut Volvulus: A Retrospective Study in a Single-Centre High-Suspicion Cohort. Frontiers in Pediatrics, 14, 1962837. https://doi.org/10.3389/fped.2026.1962837

Image Credits: AI Generated

DOI: 10.3389/fped.2026.1962837

Keywords: intestinal malrotation, midgut volvulus, ultrasound, whirlpool sign, paediatric surgery, diagnostic accuracy, children, retrospective study, superior mesenteric vessels, emergency diagnosis, diagnosing, paediatric