Tomoki Sato, Ayako Sakuma, Hanaka Kimura, Rika Okano
The SSL scale was independently associated with blood ketone levels, whereas clinically defined acute gastroenteritis was not independently associated after adjustment. These findings suggest that ketosis or fasting-related metabolic changes may contribute to the appearance of the SSL sign. The SSL scale may serve as a useful adjunctive noninvasive imaging marker for assessing metabolic status in pediatric patients with vomiting.
PURPOSE: To evaluate whether the starry sky liver (SSL) sign is more strongly associated with blood ketone levels than with clinically defined acute gastroenteritis, and to assess the clinical utility of a quantitative ultrasound index, i.e., the SSL scale, in pediatric patients presenting with vomiting.
METHODS: We retrospectively analyzed 122 pediatric patients presenting with vomiting who underwent liver ultrasonography and blood testing, including blood ketone levels. The SSL scale was calculated using grayscale histogram analysis of B-mode ultrasound images. Associations between the SSL scale and clinical variables were evaluated using correlation and multivariate regression analyses. Logistic regression and receiver operating characteristic (ROC) analyses were performed to assess the ability of the SSL scale to detect elevated ketone levels (≥ 2.0 mmol/L).
RESULTS: The SSL scale showed a significant negative correlation with log-transformed ketone levels (r = - 0.47, P < 0.001) and remained independently associated in multivariate analysis (β = - 4.87, P = 0.003). Acute gastroenteritis was not independently associated with the SSL scale. The SSL scale demonstrated good discriminative performance for detecting elevated ketone levels, with an area under the curve of 0.78 (95% confidence interval: 0.70-0.84), sensitivity of 87.3%, specificity of 59.3%, positive predictive value of 69.6%, and negative predictive value of 81.4%. These findings were consistent across different ultrasound systems.
CONCLUSION: The SSL scale was independently associated with blood ketone levels, whereas clinically defined acute gastroenteritis was not independently associated after adjustment. These findings suggest that ketosis or fasting-related metabolic changes may contribute to the appearance of the SSL sign. The SSL scale may serve as a useful adjunctive noninvasive imaging marker for assessing metabolic status in pediatric patients with vomiting.