Appendicitis in obese children

Gene Expression Profiling in Pediatric Appendicitis

Importance

Appendicitis is the most common indication for urgent surgery in the pediatric population, presenting across a range of severity and with variable complications. Differentiating simple appendicitis (SA) and perforated appendicitis (PA) on presentation may help direct further diagnostic workup and appropriate therapy selection, including antibiotic choice and timing of surgery.

Objective

To provide a mechanistic understanding of the differences in disease severity of appendicitis with the objective of developing improved diagnostics and treatments, specifically for the pediatric population.

Design, Setting, and Participants

The Gene Expression Profiling of Pediatric Appendicitis (GEPPA) study was a single-center prospective exploratory diagnostic study with transcriptomic profiling of peripheral blood collected from a cohort of children aged 5 to 17 years with abdominal pain and suspected appendicitis between November 2016 and April 2017 at the Alberta Children's Hospital in Calgary, Alberta, Canada, with data analysis reported in August 2023. There was no patient follow-up in this study.

Exposure

SA, PA, or nonappendicitis abdominal pain.

Main Outcomes and Measures

Blood transcriptomics was used to develop a hypothesis of underlying mechanistic differences between SA and PA to build mechanistic hypotheses and blood-based diagnostics.

Results

Seventy-one children (mean [SD] age, 11.8 [3.0] years; 48 [67.6%] male) presenting to the emergency department with abdominal pain and suspected appendicitis were investigated using whole-blood transcriptomics. A central role for immune system pathways was revealed in PA, including a dampening of major innate interferon responses. Gene expression changes in patients with PA were consistent with downregulation of immune response and inflammation pathways and shared similarities with gene expression signatures derived from patients with sepsis, including the most severe sepsis endotypes. Despite the challenges in identifying early biomarkers of severe appendicitis, a 4-gene signature that was predictive of PA compared to SA, with an accuracy of 85.7% (95% CI, 72.8-94.1) was identified.

Conclusions

This study found that PA was complicated by a dysregulated immune response. This finding should inform improved diagnostics of severity, early management strategies, and prevention of further postsurgical complications.

Factors contributing to uncertainty in paediatric abdominal ultrasound reports in the paediatric emergency department

BACKGROUND

Abdominal pain, which is a common cause of children presenting to the paediatric emergency department (PED), is often evaluated by ultrasonography (US). However, uncertainty in US reports may necessitate additional imaging.

OBJECTIVE

In this study, we evaluated factors contributing to uncertainty in paediatric abdominal US reports in the PED.

MATERIALS AND METHODS

This retrospective cohort study included children younger than 18 years of age who underwent abdominal US in the PED of the study hospital between January 2017 and December 2019. After exclusion, the researchers manually reviewed and classified all US reports as 'certain' or 'uncertain'. Univariate and multivariate logistic regression analyses were performed to identify the factors contributing to uncertain reports.

RESULTS

In total, 1006 patients were included in the final analysis., 796 patients were tagged as having certain reports, and 210 as having uncertain reports. Children with uncertain reports had a significantly higher rate of undergoing an additional computed tomography (CT) scan (31.0% vs. 2.5%, p < 0.001) and a longer PED median length of stay (321.0 (Interquartile range (IQR); 211.3-441.5) minutes vs. 284.5 (IQR; 191.8-439.5) minutes, p = 0.042). After logistic regression, US performed by a radiology resident (odds ratio, 5.01; 95% confidence interval, 3.63-7.15) was the most significant factor contributing to uncertainty in paediatric abdominal US reports followed by obesity and age.

CONCLUSION

Several factors contribute to uncertainty in paediatric abdominal US reports. Uncertain radiological reports increase the likelihood of additional CT scans. Measures to improve the clarity of radiological reports must be considered to improve the quality of care for children visiting the PED.

Body Mass Index Is Associated With Pediatric Complicated Appendicitis and Postoperative Complications

OBJECTIVE

To investigate the association between body mass index (BMI) spectrum and complicated appendicitis and postoperative complications in pediatric patients.

BACKGROUND

Despite the impact of being overweight and obese on complicated appendicitis and postoperative complications, the implications of being underweight are unknown.

METHODS

A retrospective review of pediatric patients was conducted using NSQIP (2016-2020) data. Patient's BMI percentiles were categorized into underweight, normal weight, overweight, and obese. The 30-day postoperative complications were grouped into minor, major, and any. Univariate and multivariable logistic regression models were performed.

RESULTS

Among 23,153 patients, the odds of complicated appendicitis were 66% higher in underweight patients [odds ratio (OR)=1.66; 95% CI: 1.06-2.59] and 28% lower in overweight patients (OR=0.72; 95% CI: 0.54-0.95) than normal-weight patients. A statistically significant interaction between overweight and preoperative white blood cells (WBCs) increased the odds of complicated appendicitis (OR=1.02; 95% CI: 1.00-1.03). Compared to normal-weight patients, obese patients had 52% higher odds of minor (OR=1.52; 95% CI: 1.18-1.96) and underweight patients had 3 times the odds of major (OR=2.77; 95% CI: 1.22-6.27) and any (OR=2.82; 95% CI: 1.31-6.10) complications. A statistically significant interaction between underweight and preoperative WBC lowered the odds of major (OR=0.94; 95% CI: 0.89-0.99) and any complications (OR=0.94; 95% CI: 0.89-0.98).

CONCLUSIONS

Underweight, overweight, and interaction between overweight and preoperative WBC were associated with complicated appendicitis. Obesity, underweight, and interaction between underweight and preoperative WBC were associated with minor, major, and any complications. Thus, personalized clinical pathways and parental education targeting at-risk patients can minimize postoperative complications.

The Impact of Obesity on Perioperative Outcomes for Children Undergoing Appendectomy for Acute Appendicitis: A Systematic Review

Today, the prevalence of obesity in the pediatric population has increased dramatically. Acute appendicitis (AA) is the most common surgical condition among pediatric patients. We aimed to investigate the impact of obesity on postoperative outcomes in terms of operative time (OT), length of stay (LOS), surgical site infection (SSI), overall complications, adverse events, and mortality in children undergoing appendectomy for acute appendicitis. An extensive search of the literature in PubMed and Google Scholar was conducted to evaluate the outcomes of normal weight (NW), overweight (OW), and obese (OB) children who underwent appendectomy. Although no statistically significant differences were noted in perioperative outcomes and overall postoperative complications between OW/OB and NW children in the majority of the included studies, prolonged OT and LOS and SSI were found in some studies. Moreover, no differences in terms of readmissions and ED visits were recorded. We conclude that the impact of obesity on postoperative outcomes for children undergoing appendectomy for AA is unclear, and, therefore, no safe conclusions can be drawn with the currently available data. Due to the lack of high-quality studies, further research is required to optimize the surgical approach and prevent unwarranted complications.

Determining the impact of body mass index on ultrasound accuracy for diagnosing appendicitis: Is it less useful in obese children?

BACKGROUND

Ultrasonography (US) is the preferred imaging for suspected pediatric appendicitis. We hypothesize that children with elevated Body-Mass-Index-for-age percentile (BMIP) may be more likely to have an inaccurate or equivocal (IE) US.

METHODS

After IRB approval, a four-year review was performed on pediatric patients evaluated for appendicitis by US. The CDC BMIP Calculator was used. IE subgroups were analyzed together for comparison against the accurate group.

RESULTS

1059 patients were included: median age 11.3 years (IQR: 8.2, 14.6), 506 (47.8%) males. Median BMIP was 65.9 (IQR: 33.9, 89.6). US accurately diagnosed 857 (80.9%), incorrectly diagnosed 76 (7.2%), 126 (11.9%) were equivocal. Overall sensitivity was 0.85, specificity 0.96, PPV 0.93 and NPV 0.91. Obese children (BMIP ≥95%), had higher odds of IE US (OR: 1.86, 95% CI: 1.28, 2.70; p = 0.001). When analyzed by sex, risk increased in obese males (OR: 2.55, 95% CI:1.53, 4.24; p = 0.0003) but normalized in obese females (OR: 1.30, 95% CI:0.74, 2.28; p = 0.35).

CONCLUSIONS

An elevated BMIP may increase difficulty in visualizing the appendix, resulting in inaccurate or equivocal findings. This risk is seen specifically in obese males. If US findings do not correlate with clinical assessment in obese children with abdominal pain, further evaluation may be warranted.

The use of computed tomography versus clinical acumen in diagnosing appendicitis in children: A two-institution international study

BACKGROUND

Appendicitis in children can be diagnosed utilizing clinical and laboratory findings, with the assistance of ultrasound (US) and/or computed tomography (CT). However, repeated exposure to ionizing radiation increases the lifetime risk of cancer. We compared the work-up of suspected appendicitis between a children's hospital in the United States (USA) and one in Spain to identify differences in imaging use and associated outcomes.

METHODS

A two-institution retrospective review was performed for surgical consultations of suspected appendicitis from 2015-2017. We compared imaging use, the utilization of overnight observation, and diagnostic accuracy rates between the two centers.

RESULTS

A total of 1,952 children were evaluated. Among the 1,288 in the USA center, 754(58.5%) underwent CT during their evaluation. The most common imaging modality was US only (39.9%), then CT only (39.3%), CT+US (19.3%), and no imaging (i.e. only clinical acumen) (1.6%). In Spain, only 19 (2.9%) of 664 children underwent CT compared to the USA (p < 0.0001). Only clinical acumen was the most common modality employed (48.6%), followed by US only (48.5%), US+CT (2.4%), and CT only (0.5%). In the USA, 16.8% were observed overnight, 2.3% of whom received no imaging. In Spain, 33.4% were observed overnight, 32.4% of whom had no imaging (p < 0.0001). The accuracy rates for diagnosing appendicitis in the USA and Spain centers were 94.7% and 95.1%, respectively.

CONCLUSION

Use of clinical acumen and/or US have similar clinical outcomes and similar accuracy rates compared to heavy reliance on CT imaging for diagnosing appendicitis, with associated decrease in radiation exposure. The disparate diagnostic approach of the two centers may reflect that physical examination is a dying art in North America.

LEVEL OF EVIDENCE

III.

Impact of overweight/obesity on clinical outcomes after reduction for intussusception in children

PURPOSE

Childhood obesity is a worsening epidemic. Little is known about the impact of overweight and obesity (OV-OB) on clinical outcomes after reduction for intussusception in children. The aim of this study was to compare clinical outcomes after primarily air enema reduction for intussusception in grouped OV-OB (body mass index-for-age percentile ≥ 85) pediatric patients compared with no OV-OB patients.

METHODS

A retrospective study of 564 children who had undergone intussusception reduction via pneumatic reduction (PR) from April 2018 to January 2020 was conducted with assessments of demographic data, clinical symptoms, pre-reduction examination, and reduction results. One-to-one propensity score matching (PSM) was performed to compare clinical outcomes between patients with and without OV-OB, and the risk factors affecting recurrence and surgical reduction were analyzed in the PSM population.

RESULTS

Of the 564 patients, 132 cases (23.4%) were OV-OB (overweight: 95 cases; obesity: 37 cases). In the propensity-matched analysis, the OV-OB group showed a significant increase in surgical reduction (10.2% versus 0.9%, P = 0.005) and recurrence (47.2% versus 10.2%, P < 0.001), excretion time of carbon powder after PR (median: 11.2 h versus 8.4 h, P < 0.001), higher maximum pressure of PR (median: 10.2 kPa versus 7.8 kPa, P < 0.001), and number of PR attempts (mean: 2.0 versus 1.4, P < 0.001). There were no significant differences in the reasons for surgery (PR failure or bowel perforation), time to recurrence (early or late), and the times of recurrences ≥ 2. After applying the multivariate logistic regression analysis, we found that OV-OB and white blood cell count ≥ 20 × 10⁹/L were risk factors for both surgical reduction and the recurrence of intussusception.

CONCLUSION

This study suggested that childhood OV-OB was associated with the failure of PR and recurrence of intussusception after reduction, which should be paid more attention in clinical practice.

Risk factors of postoperative adhesive bowel obstruction in children with complicated appendicitis

PURPOSE

Postoperative adhesive bowel obstruction (ABO) is a common complication especially in complicated appendicitis. This study aimed to analyze the risk factors for ABO following appendectomy in children with complicated appendicitis, and establish a scoring model for predicting postoperative ABO and treatment option to relieve the obstruction.

METHODS

From December 2014 to January 2020, all files of consecutive patients with complicated appendicitis underwent appendectomy were reviewed. Univariate and multivariate analyses were used to screen out the risk factors of postoperative ABO, and establish a scoring model for predicting postoperative ABO and surgical relief to relieve the obstruction.

RESULTS

Of the 780 patients, 87 (11.2%) had ABO following appendectomy, including 27 who underwent surgical relief. Age ≤ 6 years, overweight and obesity, duration of symptoms ≥ 36 h, C-reactive protein ≥ 99 mg/L, duration of operation ≥ 60 min, intraoperative peritoneal lavage, and postoperative flatus time ≥ 20 h were independent risk factors for postoperative ABO. The final scoring model for postoperative ABO included factors above, and exhibited a high degree of discrimination (area under the curve [AUC]: 0.937; 95% confidence interval [CI] 0.913-0.960) corresponding to an optimal cut-off value of 6: 82.8% sensitivity, 92.6% specificity. Furthermore, the scoring model showed a sensitivity of 74.1% and a specificity of 91.7% for patients wo underwent surgical relief to relieve obstruction with the optimal cut-off value of 9.

CONCLUSION

Risk factors for postoperative ABO should be taken seriously in children with complicated appendicitis. The scoring model is a novel but promising method to predict postoperative ABO and provide reference for clinical decision-making to relieve the obstruction.

Evaluating Changes in Diagnostic Accuracy of Ultrasound for Appendicitis: Does Practice Make Perfect?

BACKGROUND

Ultrasound (US) is the preferred method of initial evaluation for appendicitis in pediatrics. However, limited accuracy of US for appendicitis is an obstacle to implementation of US-first protocols at facilities less experienced with US.

OBJECTIVES

The primary objective was to demonstrate changes in diagnostic accuracy of US for appendicitis over time, after implementation of an US-first protocol. Secondary objectives included evaluating trends in utilization and factors associated with accuracy of US.

METHODS

We reviewed 5 years of pediatric emergency department encounters that included US evaluations for appendicitis. The primary outcome was conclusive US (fully visualized normal appendix or unequivocal appendicitis) vs. equivocal US (partially visualized or nonvisualized appendix). We also analyzed rates of conclusive US over time; accuracy, sensitivity, and specificity of US for appendicitis; and associations of US accuracy with patient gender, body mass index, and ultrasonographer's experience.

RESULTS

A conclusive US report was found in 267 of 1058 encounters (25.2%); overall accuracy rate was 24.5%. Over 5 years, the diagnostic accuracy of US for appendicitis improved significantly from 13.9% to 31.5% (p = 0.001). Overall sensitivity was 80.7% and specificity was 77.6%. Male gender and dedicated US of the appendix were significantly associated with conclusive US (ps < 0.001). Higher body mass index was significantly associated with equivocal US (p < 0.001). Ultrasonographer experience was not significantly associated with conclusive US (p = 0.22).

CONCLUSIONS

An US-first imaging protocol for appendicitis in children shows chronologic improvement in diagnostic accuracy. This may provide encouragement to facilities using computed tomography-based diagnostic protocols to implement US-first protocols to reduce childhood radiation exposure.

Comparison of conservative treatment with appendectomy for acute uncomplicated pediatric appendicitis: a meta-analysis

Aim: We aimed to compare conservative treatment with surgery for uncomplicated pediatric appendicitis to estimate effectiveness and safety. Methods: Data recorded until September 2018 were searched, and relevant academic articles from PubMed, EMBASE, the Cochrane Library and other libraries were selected. STATA version 13.0 (Stata Corporation, TX, USA) was used for statistical analysis. Results: We identified nine eligible papers. The study reported a significant difference in the success rate of treatment in 1 month and in 1 year, and no difference in the incidence of complications. The patients with fecaliths showed low treatment efficacy in conservative treatment group (p < 0.05). Conclusion: Standardized conservative treatment as inpatients for pediatric appendicitis is safe and feasible. Appendectomy was the better choice for patients with fecaliths.

A clinical trial evaluating the laryngeal mask airway-Supreme in obese children during general anesthesia

INTRODUCTION

The laryngeal mask airway (LMA)-Supreme is a disposable double-lumen laryngeal mask airway that is widely used in clinical practice. However, its use in obese children has not been evaluated. The aim of this study was to determine whether the LMA-Supreme could perform equally as well as endotracheal intubation in obese children having a minor surgical procedure.

MATERIAL AND METHODS

After ethical board approval, 100 obese male children receiving non-emergent appendectomy for chronic appendicitis or surgery to correct concealed penis were randomly divided into an endotracheal intubation group and an LMA-Supreme group. Endotracheal intubation was performed under direct vision laryngoscopy. In the LMA group, a size-3 LMA-Supreme was placed and a stomach tube inserted via the drainage tube of the mask. Cardiovascular and respiratory parameters, time taken for placement, placement attempts, time to removal of the endotracheal tube/LMA, length of stay in the post-anesthesia care unit (PACU), and complications were recorded.

RESULTS

Insertion time was significantly longer (p < 0.001) in the LMA-Supreme group than in the endotracheal intubation group. Peak airway pressure was significantly higher, and pulmonary compliance and PACU stay time lower in the LMA-Supreme group. No significant differences between endotracheal intubation and the LMA-Supreme were seen in other parameters, except for a higher incidence of coughing in the endotracheal intubation group.

CONCLUSIONS

The LMA-Supreme can be easily inserted and effectively used for airway management in obese children undergoing minor surgery.

Laparoscopic Extracorporeal Appendectomy in Overweight and Obese Children

Background and Objectives:

To compare surgical outcomes of overweight and obese patients with acute appendicitis who have undergone single-port extracorporeal laparoscopically assisted appendectomy (SP) with those who have had conventional 3-port laparoscopic appendectomy (TP).

Methods:

This single-center retrospective chart review included patients 21 years of age and younger with a preoperative diagnosis of appendicitis who underwent laparoscopic appendectomy from January 2010 through December 2015. Cases of gangrenous and perforated appendicitis were excluded. Subgroup analyses of patients with acute appendicitis were performed. Operative time (OT), length of stay (LOS), and cost were compared between groups stratified by body mass index (BMI) and operative technique.

Results:

A total of 625 appendectomies were performed—457 for acute appendicitis. Sixty-eight patients were overweight. The SP technique (n = 30) had shorter OT (median minutes, 41 vs 68; P < .001), lower cost (median , $5741 vs $8530; P < .001), and shorter LOS (median hours, 16 vs 19; P = .045) than the TP technique had (n = 38). Seventy patients were obese: 19 were treated with SP and 51 with TP. LOS did not differ significantly between the SP and TP groups, but subjects treated with SP had shorter OT (median minutes, 39 vs 63; P < .001) and lower cost (median, $6401 vs $8205; P = .043).

Conclusions:

The SP technique for acute appendicitis was found to have a significantly shorter OT and lower cost in all weight groups. There were minimal differences in LOS. SP should be considered in patients with acute appendicitis, regardless of their weight.

Obesity and single-incision laparoscopic appendectomy in children

BACKGROUND

Single-incision laparoscopic appendectomy (SILA) has emerged as a less-invasive alternative to conventional laparoscopy. The purpose of this study was to assess the impact of body habitus on outcomes after SILA in the pediatric population.

METHODS

A retrospective review of 413 patients who underwent SILA from 2012 to 2015 was performed. Body mass index (BMI) was calculated, and the BMI percentile was obtained per Center for Disease Control guidelines. Standard definitions for overweight (BMI 85th-94th percentile) and obese (BMI > 95th percentile) were used. General demographic and outcome data were analyzed.

RESULTS

SILA was performed in 413 patients during the study period, of which 66.3% were normal weight, 16% were overweight, and 17.7% were obese. There were no significant differences in age at presentation, time to diagnosis, or intraoperative classification of appendicitis. There were no significant differences in operative time (27.0 ± 9.1 versus 27 ± 9.8 versus 28.4 ± 9.4 min, P = 0.514), postoperative length of stay (0.97 ± 1.65 versus 1.53 ± 4.15 versus 1.14 ± 2.27 d, P = 0.214), 30-d surgical site infections (6.9% versus 12.1% versus 8.2%, P = 0.377), emergency department visits (8.4% versus 10.6% versus 11%, P = 0.726), or readmissions (4.7% versus 4.1% versus 4.5%, P = 0.967) among normal, overweight, and obese groups.

CONCLUSIONS

Our results indicate that obesity does not significantly impact outcomes after SILA. SILA can be performed in overweight and obese children with no significant difference in operative time, length of stay, or incidence of surgical site infection. SILA should continue to be offered to overweight and obese children.

The influence of underweight and obesity on the diagnosis and treatment of appendicitis in children

PURPOSE

The impact of lower body mass index (BMI) on appendicitis has never been addressed. We investigated whether different BMIs affect the diagnosis and treatment of appendicitis in children.

METHODS

The correlation between BMI and diagnosis accuracy and treatment quality was evaluated by retrospective analysis of 457 children diagnosed with appendicitis. Based on BMI percentiles, patients were classified as either underweight (n = 36), normal weight (n = 346), overweight (n = 59), or obese (n = 16). Diagnosis accuracy was measured by negative appendectomy rate, perforation rate, and number of consultations. Treatment quality was measured by complication rate and length of hospital stay.

RESULTS

Underweight patients had the highest negative appendectomy (OR 3.00, P = 0.008) and complication (OR 2.75, P = 0.041) rate. BMI did not influence perforation rate or number of consultations. Both underweight and obese patients stayed in the hospital longer than normal weight patients (regression coefficient 2.34, P = 0.001, and regression coefficient 9.40, P < 0.001, respectively). Furthermore, in obese patients, the hospital stay after open appendectomy was prolonged compared to laparoscopic appendectomy (P < 0.001). No such differences were observed in patients with lower BMI.

CONCLUSIONS

Underweight children are misdiagnosed more often, stay in hospital longer, and experience more postoperative complications than children of normal weight. Obesity is associated with longer hospital stays. Laparoscopic appendectomy might shorten the length of hospital stays in these patients. We conclude that in addition to obesity, underweight should also be considered a risk factor for children with appendicitis.

The impact of obesity on laparoscopic appendectomy: Results from the ACS National Surgical Quality Improvement Program pediatric database

BACKGROUND

Childhood obesity is a worsening epidemic. Little is known about the impact of elevated BMI on perioperative and postoperative complications in children who undergo laparoscopic surgery. The purpose of this study was to examine the effects of obesity on surgical outcomes in children using laparoscopic appendectomy as a model for the broader field of laparoscopic surgery.

STUDY DESIGN

Using the Pediatric National Surgical Quality Improvement Program (NSQIP) data from 2012, patients aged 2-18years old with acute uncomplicated and complicated appendicitis who underwent laparoscopic appendectomy were identified. Children with a body mass index (BMI)≥95th percentile for their age and gender were considered obese. Primary outcomes, including overall morbidity and wound complications, were compared between nonobese and obese children. Multivariate regression analysis was conducted to identify the impact of obesity on outcome.

RESULTS

A total of 2812 children with acute appendicitis who underwent appendectomy were included in the analysis; 22% were obese. Obese children had longer operative times but did not suffer increased postoperative complications when controlling for confounders (OR 1.3, 95% CI: 0.83-0.072 for overall complications, OR 1.3, 95% CI: 0.84-1.95 for wound complications).

CONCLUSIONS

Obesity is not an independent risk factor for postoperative complications following laparoscopic appendectomy. Although operative times are increased in obese children, obesity does not increase the likelihood of 30-day postoperative complications.

Obesity and symptomatic cholelithiasis in childhood: epidemiologic and case-control evidence for a strong relation

OBJECTIVES

The aims of this study were to correlate the temporal trends in obesity prevalence with hospitalization rates for symptomatic cholelithiasis and to estimate the strength of the association between obesity and symptomatic cholelithiasis in patients hospitalized at an urban children's hospital in New York serving a multiethnic population.

METHODS

Using obesity prevalence data from the National Health and Nutrition Examination Survey and the rates of hospitalization for cholelithiasis derived from the Kids' Inpatient Database for 1997-2007, we estimated a correlation and a linear regression. We conducted a retrospective, case-control study in which each case ages 4 to 20 years with symptomatic cholelithiasis was individually matched to a control admitted with appendicitis based on age, sex, ethnicity, and race.

RESULTS

The prevalence of obesity and the cholelithiasis hospitalization rate increased over time (R=0.87, P=0.0025). For every 1% increase in the obesity rate among children, the rate of hospitalization for gallstones increased by 0.65/100,000 children (R²=0.75, P=0.0025, 95% confidence interval [CI] 0.32-0.99). The odds ratio for obesity in cases versus controls was 5.78 (n=518, P<0.0001, 95% CI 3.50-9.53). We found a significant dose-response effect, which showed that for every 1 z score increase in body mass index, the risk of cholelithiasis was increased by 79% (P<0.0001, 95% CI 1.5-2.13).

CONCLUSIONS

The national trend in the prevalence of obesity from 1997 to 2009 was significantly correlated with increasing rates of hospitalization for pediatric cholelithiasis. Our case-control study suggests that obesity is a significant risk factor for hospital admission because of cholelithiasis.