Value of Ultrasound in Diagnosing Perforation of Congenital Choledochal Cysts in Children.

OBJECTIVES: This study aimed to investigate the diagnostic value of ultrasound in children with perforation of congenital choledochal cysts. METHODS: Eligible patients recruited from January 2004 to December 2018 in our hospital were enrolled in this retrospective study. A total of 59 cases of congenital choledochal cysts with perforation were defined as the perforation group, and 100 cases of congenital choledochal cysts without perforation with similar symptoms were defined as the control group. Clinical features were analyzed and compared between the groups. The differential efficacy of varied diagnostic criteria was evaluated by a receiver operating characteristic analysis. RESULTS: Significant differences were found between the groups with respect to clinical characteristics (abdominal pain, vomiting, fever, and abdominal distention; all P < .01) and the disease onset age (P < .001), but the diagnostic efficacy of both was poor (both areas under the curve, <0.7). The interruption of bile duct continuity only occurred in the perforation group with high specificity of 100% but poor sensitivity of 18.6%. The discrimination of combined features was significantly better (area under the curve, 0.936) than that of the disease onset age and clinical characteristics, with observed sensitivity and specificity of 93.2% and 94.0%, respectively. CONCLUSIONS: Using specific features, ultrasound can effectively diagnose perforation of a congenital choledochal cyst in children.

Application of high-frequency ultrasound in the diagnosis of gastrointestinal magnet ingestion in children.

Background: The incidence of magnet ingestion by children has recently increased in China. Magnet ingestion is associated with an extremely high risk of gastrointestinal damage because loops of bowel can become trapped and squeezed between multiple magnets in different locations. However, the lack of imaging sensitivity makes clinical decision-making difficult. Objective: This study was conducted to investigate the performance of ultrasound in diagnosing gastrointestinal magnet ingestion in children. Methods: From April 2017 to February 2021, all children with a history of magnet ingestion or a diagnosis of gastrointestinal magnet as shown by x-ray or ultrasound in our hospital were included as study candidates. Patients who were lost to follow-up or had known malformations of the gastrointestinal tract were excluded. Eligible patients were those with surgical or endoscopic confirmation of gastrointestinal magnet, those who passed the magnet out of the alimentary tract without assistance, and those with confirmed absence of the magnet on abdominal x-ray examination after 1 month of conservative treatment. All eligible patients' ultrasound and x-ray examination data were evaluated. The sensitivity, specificity, and area under the curve (AUC) of ultrasound was calculated for diagnosing magnet ingestion, locating the magnet (stomach, small intestine, or colon), and confirming the phenomenon of wall entrapment. Results: Of 112 patients, 107 had a magnetic foreign body and 5 did not. Magnets were correctly detected by ultrasound in 97 patients, with an observed sensitivity of 90.65% and specificity of 100%. Satisfactory sensitivity was obtained for ultrasound localization of gastric magnets (96.30%) and small intestinal magnets (100.00%), but sensitivity for ultrasound localization of colonic magnets was relatively poor (73.33%). The discrimination of wall entrapment by ultrasound was good (AUC = 0.93), with an observed sensitivity and specificity of 92.00% and 93.62%, respectively. Conclusions: Ultrasound can be used to locate gastrointestinal magnets (in the stomach, small intestine, or colon) with good clinical efficacy in identifying wall entrapment.

Development and Validation of a Nomogram Incorporating Ultrasonic and Elastic Findings for the Preoperative Diagnosis of Biliary Atresia.

RATIONALE AND OBJECTIVES: To develop and validate a nomogram that incorporates the gallbladder morphology, hepatic elasticity, and demographic information for the prediction of biliary atresia (BA) in children. MATERIALS AND METHODS: A total of 294 consecutive patients under the age of 70 days with cholestasis and suspected symptoms of BA were enrolled in this study, who were divided into a training cohort (150 patients) and a validation cohort (144 patients). Ultrasonography and two-dimensional shear wave elastography were performed for each patient prior to knowing the final diagnosis. Multivariate logistic regression was used to analyze the gallbladder morphologic feature in the sonogram (absence of gallbladder, small gallbladder, lower postprandial gallbladder contractibility, or abnormal gallbladder wall), hepatic elasticity and clinical data from the training cohort, and a diagnostic nomogram for BA was subsequently developed. The performance of the nomogram was respectively evaluated with respect to the discrimination and calibration in every cohort. RESULTS: The multivariate analysis showed that the factors of age (p = 0.009), gallbladder morphology (p = 0.001) and hepatic elasticity (p < 0.001) could serve as independent predictive factors to differentiate between BA and other causes of cholestasis. The nomogram incorporating these three parameters showed good discrimination and satisfactory calibration, indicating a better performance compared to using only the gallbladder morphologic features and hepatic elasticity. The observed area under the receiver operator characteristic curve in the training cohort and validation cohort was 0.939 (p < 0.001) and 0.942 (p < 0.001), respectively, with a sensitivity of 95.5% and a specificity of 83.4% in the combined cohort. CONCLUSION: The established nomogram shows a favored and improved predictive value for the diagnosis of BA.

Ultrasonographic diagnosis of urinary calculus caused by melamine in children.

BACKGROUND: Intake of melamine can cause renal and ureteral lithiasis in infants and children. The present study aimed to understand the value of ultrasonography in the diagnosis of renal and ureteral lithiasis in infants and young children caused by melamine, and the characteristics of ultrasonograms of melamine-associated calculi. METHODS: Ultrasonographic examination on the urinary system was performed for 28 332 children who ingested milk powder that was possibly tainted with melamine; 395 of the children were diagnosed by ultrasonography as having urinary calculus, and 231 cases had lump-like calculi and 164 cases had sand gravel-like calculi. The features of the calculi, the sites of obstruction and the status of hydronephrosis and hydroureterosis were analyzed. Ultrasonographic reexamination was performed for 116 patients and the findings were compared with those of the first ultrasonography, and the short-term expulsion of the calculi was evaluated. RESULTS: Most of the 395 patients with urinary lithiasis, except for those who developed renal failure, had no symptoms. The whole profile of the calculi could be seen in most of the cases, because the echogenicity of the calculi with no sharp or absent acoustical shadowing, was weaker as compared with those from calcium-containing calculi. Comet tail sign could be seen behind the echogenicity of single gravel calculus. The rate of diagnostic consistency of ureteral lithiasis between the ultrasound and the results of clinical observation (including stones expelled spontaneously or after cystoscopic intervention) in 51 cases for 76 ureters was 100%. Percutaneous renal biopsy was performed for one case, and histopathological examination showed flocculent, fine strip-like, ellipse and circular deeply stained sand gravel-like material in the renal tubules, and the circular calculi were found to be attached to the walls of the tubules. Chemical analysis of the calculi expelled from 12 cases showed that the main contents of the calculi were uric acid and melamine. Short-term ultrasound reexamination in 116 patients showed that gravel-like calculi disappeared in 80.4% of the cases; in 26 non-hospitalized cases who had lump-like calculi without hydronephrosis or hydroureterosis, none of the lump-like calculi were expelled. CONCLUSIONS: The ultrasonographic findings of urinary calculi in children caused by ingestion of melamine-tainted milk powder have a certain features as compared to the calculi containing calcium. Careful ultrasound examination can avoid missed diagnoses of ureteral calculi. Most of the gravel-like calculi can be expelled within a short period of term, while lump-like calculi can hardly be expelled. Ultrasonography is an accurate and reliable method of diagnosis of urinary calculus caused by melamine intake in children and it can be used as diagnostic method of choice although abdominal X-ray plain film can also visualize some of larger calculi.