Background. Gastrointestinal system disorders are known to be prevalent among children with autism spectrum disorder (ASD). Some ASD-associated comorbidities are abdominal pain, constipation, diarrhea, gastroesophageal reflux, sleep disturbances, epilepsy, and psychiatric problems. Nonetheless, there is still limited information about the presence of functional GI disorders (FGIDs) among children with ASD, especially in Türkiye. Using the Rome criteria, we aimed to investigate FGIDs in children with ASD. Methods. The sample of the study consisted of 68 children aged 4-10 years, diagnosed with ASD according to the DSM-5 diagnostic criteria and had scores greater than 30 on the Childhood Autism Rating Scale (CARS-2) and an age-sex matched control group (n=78). The Rome III criteria were used to evaluate FGIDs. Results. The frequency of FGIDs in the ASD group was higher (76.5%) compared to the control group (p<0.001). Compared to the control group, abdominal migraine frequency increased 10 times (p=0.012), functional constipation 7 times (p<0.001), and fecal incontinence 6 times (p<0.001) in the ASD group. Stool retention was not present in most children in the ASD group who were found to have fecal incontinence. Conclusion. In this study, the most common FGIDs in the ASD group were abdominal migraine, functional constipation, and non-retentive fecal incontinence. The finding that most children with ASD who had fecal incontinence did not show stool retention implicated social, psychological, and behavioral factors as the causes of incontinence. Raising awareness of healthcare professionals about the frequency of FGIDs in children with ASD will improve many areas in the daily lives of these children.

Background/Aims: Peutz–Jeghers syndrome (PJS) is a rare hereditary disorder linked to increased cancer risk due to specific genetic variants in the STK11 gene. This study aimed to assess disease manifestations, genetic profiles, and genotype–phenotype correlations in PJS patients. Materials and Methods: Twenty patients from 14 families with PJS who were followed up at our clinic between 2011 and 2021 were included. Genetic susceptibility to hereditary cancers was assess–ed using targeted next-generation sequencing (NGS) and multiplex ligation-dependent probe amplification (MLPA) of the STK11 gene. Clinical data were also collected and analyzed in conjunction with the genetic findings. Results: Initial symptoms appeared around 18.9 years, predominantly abdominal pain and intussusception. Mucocutaneous lesions were found in 85%, and hamartomatous polyps in 90%. Dysplastic polyps were found in 4 patients, with 3 cases of malignancy. Nextgeneration sequencing identified 11 pathogenic and 3 likely pathogenic mutations, including 3 novel STK11 variants (LRG_319: c.598- 8_601del, LRG_319: c.708_718del, and LRG_319: c.146_147del). Next-generation sequencing diagnostic rate was 78.5% (11/14), and the overall diagnostic rate with NGS and MLPA studies was 85.7% (12/14). Patients without STK11 mutations had later symptom onset and potentially lower cancer risk. Truncated mutations are associated with earlier symptoms and elevated cancer risk. Conclusion: This is the first PJS case series in Turkey using the NGS and MLPA methods. It reports 3 novel mutations and emphasizes the genotype–phenotype relationship of PJS. With further studies, the genotype–phenotype relationship of STK11 variants will be better understood. Cite this article as: Günay Aslan P, Çağlayan AO, Bora E, et al. Clinical and molecular analysis in patients with peutz–jeghers syndrome. Turk J Gastroenterol. 2024;35(5):374-384.

Background: This study aimed to evaluate the indications, efficacy, and safety of endoscopic retrograde cholangiopancreatography (ERCP) in pediatric patients at a single center in Turkey between 2017 and 2021. Methods: A retrospective review was conducted on 50 children (mean age, 12.7 years; range, 1–18 years) who underwent 65 ERCP procedures. Data collected included patient demographics, indications for ERCP, procedural details, success rates, and complications. All procedures were performed using therapeutic duodenoscopes under conscious sedation administered by an anesthesiologist. Results: The primary indications for ERCP were biliary tract issues, including choledocholithiasis (52.3%) and chronic pancreatitis (18.5%). The overall cannulation success rate was 92.3%. Multiple therapeutic interventions, such as sphincterotomies and stent placements, were often required. The most common complication was post-ERCP pancreatitis, observed in 6.1% of cases, all of which were moderate. No fatalities or serious anesthesia-related adverse events were reported. Conclusion: ERCP is an effective and safe therapeutic procedure in pediatric patients when performed in collaboration with adult gastroenterologists, despite technical challenges such as the lack of pediatric-specific duodenoscopes. The findings highlight the need for specialized pediatric ERCP equipment and suggest that centralized ERCP facilities could enhance patient outcomes in Turkey.

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) encompasses a spectrum of liver conditions and involves gut–liver axis crosstalk. We aimed to evaluate whether oral vancomycin modifies liver injury and the cecal microbiota in a methionine–choline-deficient (MCD) diet model of NASH. Male C57BL/6J mice (n = 28) were block-randomized to four groups (n = 7 each) for 10 weeks: standard diet (STD); MCD diet; STD + vancomycin (VANC); and MCD + VANC (2 mg/mouse ≈ 50 mg/kg, every 72 h). After 10 weeks, liver tissues were analyzed for histological changes, cytokine levels [interleukin-6 (IL-6), interleukin-8 (IL-8), transforming growth factor beta 1 (TGF-β1)], and immunohistochemical markers [ubiquitin and cytokeratin 18 (CK18)]. Cecal microbiota composition was evaluated with 16S ribosomal RNA (rRNA) sequencing. The MCD reproduced key NASH features (macrovesicular steatosis, lobular inflammation). Vancomycin shifted steatosis toward a microvesicular pattern and reduced hepatocyte injury: CK18 and ubiquitin immunoreactivity were decreased in MCD + VANC vs. MCD, and hepatic IL-8 and TGF-β1 levels were lower in MCD + VANC vs. STD. Taxonomically, STD mice had Lactobacillus-rich microbiota. The MCD diet alone reduced alpha diversity (α-diversity), modestly lowered Firmicutes and increased Desulfobacterota/Fusobacteriota. Vancomycin alone caused a much larger collapse in richness, depleting Gram-positive commensals and promoting blooms of Escherichia–Shigella, Klebsiella, Parabacteroides, and Akkermansia. In the MCD + VANC group, vancomycin profoundly remodeled the microbiota, eliminating key commensals (e.g., Lactobacillus) and enriching Desulfobacterota, Fusobacteriota, and Campylobacterota. Oral vancomycin in the MCD model of NASH improved liver injury markers and altered steatosis morphology, but concurrently reprogrammed the gut into a low-diversity, pathobiont-enriched ecosystem with near-loss of Lactobacillus. These findings highlight a therapeutic trade-off—hepatic benefit accompanied by microbiome cost—that should guide microbiota-targeted strategies for NAFLD/NASH.

Background/Objectives: Celiac disease (CD) is a chronic autoimmune enteropathy with increasing recognition of systemic involvement, including potential microvascular alterations. While nailfold videocapillaroscopy (NVC) is an established tool in rheumatology for assessing microcirculation, its application in pediatric CD remains unexplored. Our aim was to investigate capillaroscopic abnormalities in children with CD and assess their associations with clinical and laboratory parameters, including dietary adherence. Methods: This cross-sectional study included 76 pediatric CD patients and 76 age- and sex-matched healthy controls. All participants underwent standardized NVC evaluation, assessing capillary density, dilatation, morphology, and microhemorrhages. Clinical data, laboratory values, and dietary adherence (based on clinical symptoms and tissue transglutaminase-IgA levels) were recorded. Results: Compared to controls, CD patients exhibited significantly lower capillary density and increased frequencies of dilated capillaries, microhemorrhages, and abnormal morphologies (p < 0.001). A nonspecific NVC pattern predominated among CD patients. Capillary abnormalities were more pronounced in patients without tTG-IgA normalization (>10 U/mL) and with symptoms suggestive of gluten exposure. Additionally, the number of dilated capillaries positively correlated with age and disease duration. No significant differences were found based on ANA status. Conclusions: This is the first study to demonstrate NVC-detectable microvascular alterations in pediatric CD. Findings suggest subclinical microvascular involvement, which may be potentially modifiable through dietary adherence. NVC may serve as a non-invasive tool to detect early vascular changes and monitor systemic manifestations in pediatric CD. Longitudinal studies are warranted to clarify the reversibility and prognostic implications of these abnormalities.

Objectives: Large cell calcifying Sertoli cell tumours (LCCSCTs) are one of the infrequent causes of prepubertal gynaecomastia. Most of these tumours are in the content of Peutz–Jeghers syndrome (PJS) or other familial syndromes (Carney complex). Case presentation: Here, we report a long-term follow-up of an 8.5-year-old prepubertal boy with a diagnosis of PJS, who presented with bilateral gynaecomastia, advanced bone age and accelerated growth velocity, and were found to have bilateral multifocal testicular microcalcifications. As the findings were compatible with LCCSCT, anastrozole was initiated. Gynaecomastia completely regressed and growth velocity and pubertal development were appropriate for age during follow-up. Testicular lesions slightly increased in size. After four years of medication, anastrozole was discontinued but was restarted due to the recurrence of gynaecomastia after six months. Conclusions: Testicular tumour should be investigated in a patient with PJS who presents with prepubertal gynaecomastia. When findings are consistent with LCCSCT, aromatase inhibitors may be preferred in the treatment.