Gallbladder Motility in Children With Down Syndrome *Haydar Ali Tas ¸demir, *Melih Cevdet C ¸ etinkaya, †Cafer Polat, ‡Umit Belet, *Ayhan Gazi Kalayci, and §Seval Akbas ¸ Ondokuz Mayis University, Departments of *Paediatrics, †Surgery, ‡Radiology, and §Biochemistry, Kurupelit, Turkey ABSTRACT Objective: The aim of this study was to investigate gallbladder motility in children with Down syndrome by measuring gall- bladder volume and contraction index. Methods: This study, performed between January 2001 and December 2002 at the Ondokuz Mayis University, School of Medicine, Department of Paediatric Neurology, Samsun, Tur- key, included 21 patients with Down syndrome (study group) and 22 healthy children (control group). After an 8-hour fast, gallbladder diameters in both groups were measured in length, width, and height by ultrasonography before and 30 minutes after a test meal. The volume of gallbladder before and after a test meal was determined, and the contraction index was cal- culated. Blood triglyceride and cholesterol levels were mea- sured, and 5-hydroxyindoleacetic acid (5-HIAA) levels in urine were determined. Results: Mean gallbladder volume before test meal in the study group and controls was 8,412.4 ± 5,174 mm 3 and 16,516.8 ± 6,796.1 mm 3 (P < 0.001), respectively. The mean contraction index of the study group was 41.2% ± 19.4% and of controls, 75.0% ± 12.3% (P < 0.001). The mean triglyceride level of the study group was significantly higher than controls (P < 0.05). The mean urine 5-HIAA level of the study group was lower than controls (P < 0.05). Conclusion: CI was lower in patients with Down syndrome, suggesting gallbladder hypomotility. Hypomotility may be a feature associated with the high prevalence of gallstones in Down syndrome. JPGN 39:187–191, 2004. Key words: Down syndrome—Gallbladder motility—5-HIAA. Down syndrome (DS) or trisomy 21 is the most com- mon human trisomy with a prevalence of approximately 1 in 650 to 700 live births (1–3). Many gastrointestinal complications are associated with DS including duodenal stenosis or atresia, imperforate anus, Hirschsprung dis- ease, tracheoesophageal fistula, and esophageal atresia. Gastroesophageal reflux, constipation, and some motility disorders also have been reported in DS (3–7). Gallstones are rare in childhood. An ultrasonographic study in 3,500 neonates without risk factors for gall- stones found a 0.5% prevalence of cholelithiasis (8). Pa- lasciano et al. (9) reported a 0.13% prevalence of gall- stones in 1,570 healthy children from 6 to 19 years old. Some recent reports suggest that the incidence of gall- stones is greater in children with DS than in healthy children (10–14). Llerna et al. (12) found gallstones in 10 (6.9%) of 145 children with DS. Toscano et al. (14) reported 6 (4.7%) patients with gallstone among 126 children with DS. Normal gallbladder motility is crucial in preventing the formation of gallstone (15). A decrease in gallbladder motility with insufficient emptying may produce crystal- lization of the gallbladder bile (16,17). It has been ex- perimentally demonstrated that impaired gallbladder mo- tility is the most important factor in gallstone formation (18). Muscular hypotonia is a well-known abnormality in patients with DS. It is thought that this problem might be an important factor in producing gastrointestinal hypo- motility (2,5) and potentially, gallbladder hypomotility. The aim of our study is to investigate whether there is hypomotility in the gallbladder of children with DS as measured by ultrasonographically determined gallblad- der volume and contraction index. MATERIALS AND METHODS: This study, performed between January 2001 and December 2002 at Ondokuz Mayis University, School of Medicine, De- partment of Paediatric Neurology, Samsun, Turkey, included 21 patients with DS diagnosed by cytogenetic and clinical in- vestigations (study group), and 22 healthy children (control group). There was no statistically significant difference with in the demographic properties of the groups (Table 1). Received September 9, 2003; accepted March 13, 2004. Address correspondence and reprint requests to Haydar Ali Tas ¸demir, MD, Department of Pediatry, Ondokuz Mayis University, School of Medicine, 55139 Kurupelit/Samsun, Turkey (e-mail: htasdemir@ omu.edu.tr). Journal of Pediatric Gastroenterology and Nutrition 39:187–191 © August 2004 Lippincott Williams & Wilkins, Philadelphia 187