Division of Pediatric Gastroenterology, Hepatology and Nutrition renders services in fields of disorders and diseases of mouth, esophagus, stomach, small intestine and colon, liver, gall bladder and pancreas from birth to 18 years of age as well as evaluation of nutrition and growth of healthy and diseased children. All of these services are delivered in cooperation with various departments such as genetics, metabolic diseases, radiology, pathology, pediatric surgery, otorhinolaryngology and pediatric allergy. All kinds of medical support that may be needed by our outpatients and inpatients at our hospital can be rapidly provided thanks to high-standard technical equipment and auxiliary teams of our university.

Work Program and Services

Our work program includes all fields related to pediatric gastroenterology, hepatology and nutrition such as monitoring the outpatients and inpatients, preparation for and follow-up after liver transplant, diagnosis and treatment of chronic gastrointestinal diseases, tube and intravenous nutrition at Pediatric Gastroenterology, Hepatology and Nutrition Unit. There are 2 outpatient rooms, office of medical coordinator of pediatric liver transplant and training. All kinds of diagnostic and therapeutic procedures can be performed for childhood diseases of organs, such as stomach, intestines, liver and pancreas, with proper equipment and qualified teams at well-equipped endoscopy unit. The state-of-the-art biochemistry, microbiology, pathology and hematology laboratories and translational research laboratory of our hospital offers crucial advantages in terms of patient care and research.
Our division actively deals with education of fellows, residents and medical students. In addition, in-service trainings are periodically organized in cooperation with different departments. Case meetings are regularly held together with relevant departments especially to solve complex cases easily. Our specialists actively participate in both local and international medical meetings. KUTTAM (Koç University Research Center for Translational Medicine) maintains its educational and research activities in fields of basic sciences with its research laboratory team. Our team regularly participates in these meetings within the scope of training and studies:

- Liver transplant council - weekly
- Pathology council - weekly
- Pediatric radiology and interventional radiology - weekly
- Aerodigestive council – twice a month
- PTLD (Post-transplantation lymphoproliferative disease) - monthly
- Article and seminar meetings – weekly
The scientific studies conducted by our pediatric gastroenterology, hepatology and nutrition division that contribute to the scientific world are among the foundations that make our division one of important reference center in local and international platforms*. The studies conducted in our unit intend to provide patients with better treatment and care. For this purpose, various studies are maintained in clinical and research laboratories regarding the cause and course of hepatic diseases, minimizing the post-transplant medication therapies and use of novel treatment options for allergic gastrointestinal disorders.

Major Pediatric Diseases Diagnosed and Treated at our Gastroenterology, Hepatology and Nutrition Unit Are As Follows:

This is one of the most common problems from infancy to adolescence. This condition may either be a result of decreased calorie need at certain stages of growth or an indicator of a critical disease. In addition to a detailed diet history, appropriate recommendations are made based on evaluation of diet content and pattern as well as neurological and psychosocial development. In this group, wrong dietary contents and amounts, reflux, food allergies, diseases and sensitivities involving the esophagus, stomach and intestines, slow gastric and intestinal functions are the most commonly faced and treated problems.
Gastroesophageal reflux:
Reflux is a condition characterized with gastric content flowing back into the esophagus and it can be seen at any age starting from infancy. In addition to diagnosis and treatment of reflux, diet arrangement-support is also provided at our clinic.

These can be seen at any age and may have various symptoms. Symptoms may include bloody stool, diarrhea, abdominal pain, constipation, idiopathic joint pain, growth retardation, lack of appetite, mouth sores - aphthous ulcers, delayed growth in children.

Early diagnosis is of vital importance for celiac disease, which is one of the most common diseases in our country.  Celiac disease develops with abnormal response of immune system to a substance called gluten which is found in cereals such as wheat, barley, rye. The disease may develop at any age and can cause numerous symptoms including growth retardation, chronic diarrhea, abdominal distension, fatigue, lack of appetite, vomiting, short stature, anemia, abnormal parameters in hepatic tests due to damage in intestines. The disease is screened with blood tests while final diagnosis is made with endoscopy. The treatment is gluten-free diet for lifetime.  In addition to diagnosis, dietary support is also provided to the patients.

Abdominal pain in children is a common condition. The underlying cause depends on age.  However, problems in all organs can be expressed as abdominal pain at any age. Therefore, it can be a symptom of all conditions from esophagus to colon problems, from gall bladder disorders to rheumatoid diseases, from food allergies to migraine and constipation. For this reason, the underlying cause of abdominal pain is identified with multidirectional approach and treated at our clinic.

This is one of the most common reasons of unexplained abdominal pain and food refusal in children. Constipation is a problem that is not sufficiently known and it is one of the disorders that can be eliminated with drugs, behavioral changes and toilet training. Constipation means rare, painful and solid defecation. Painful defecation of low amount of feces every day, large-scaled painful defecation are included in this definition. Being one of the most common problems of childhood period, constipation corresponds to 3 to 10 percent of reasons for presenting to general pediatrics outpatient clinics and 25 percent of presentations to pediatric gastroenterology outpatient clinics. The frequency increases especially in pre-school period.

The condition may manifest itself with food refusal and pause in growth, vomiting, diarrhea, constipation and abdominal pain. Negative results in allergy tests do not necessarily mean that there is allergic gastrointestinal disease. Our team helps our patients especially regarding eosinophilic esophagitis that is defined as asthma of esophagus with multidisciplinary approach.

While evaluating the underlying cause for children who cannot tolerate nutrition, nutritional support is provided with or without a tube at any age group at inpatient and outpatient settings. A tube is placed through the stomach (PEG) under endoscopic guidance for children with neurologic problem and life quality of these children is boosted and it is ensured that they receive the nutrients without any risks.

Liver is the factory of body. Therefore, conditions of infections involving the liver, congenital developmental disorders, drugs and herbal supplements, excessive weight gain may impair the hepatic functions.

What are the symptoms of liver diseases in children?
Regardless of the cause, there are common clinical symptoms of liver diseases. Patients with loss of hepatic cells who do not have any complaint can present with incidentally detected hepatic blood test abnormalities while symptoms including jaundice, itching, diarrhea, abdominal distension, abdominal pain, dark discoloration of urine, shortness of breath, bone fractures may develop. The symptoms change depending on age and underlying disease. Blood tests, radiologic methods, urinalysis, liver biopsy and genetic tests are used for diagnosis. We provide the patients with all kinds of diagnostic and therapeutic methods at pediatric liver diseases outpatient clinic of our clinic.  Treatment differs depending on the cause at early stage of liver diseases. These treatment results may eliminate or reverse the disease. However, when a terminal stage disease called cirrhosis develops in liver, there is no chance of treatment except for liver transplantation.
Abnormalities in Hepatic Function Tests
Hepatic function tests are indicators based on liver or bile ducts. They may be caused by liver diseases or the test values may be abnormal in case of conditions such as muscle diseases and connective tissue diseases. Impaired values in hepatic function tests may be noted in many cases such as infections, metabolic diseases, hepatosteatosis, overweight-metabolic syndrome, celiac disease, medication induced liver damage, cystic fibrosis, familial Mediterranean fever, inflammatory bowel disease. Therefore, the patients should be evaluated in light of a detailed history and physical examination and diagnosis should be made with appropriate methods. Treatment differs depending on diagnosis. Our department provides multidirectional services with our physicians who are specialists in field of pediatric liver diseases.
Autoimmune Hepatitis-Primary Sclerosing Cholangitis
This condition is when the immune system perceives the hepatic cells as foreign and harmful. Although it is assumed that the condition may be resulted from genetic predisposition, current medications and previous infections, the underlying cause is not exactly known. Symptoms like sudden jaundice, fatigue, abdominal distension, abdominal pain, itching and rashes, or it may be manifested by only abnormal hepatic test results on laboratory analyses. The condition may be sudden or insidious in onset. In any case, it is required to identify the condition at early stage and provide treatment promptly. If the condition is left untreated, cirrhosis may develop, resulting in liver failure. A wide variety of treatment can be applied to manage this disease at our Liver Diseases Outpatient Settings.  Also, researches regarding new treatment modalities conducted together with international autoimmune hepatitis group are maintained at our outpatient settings.
The condition develops as a result of congenital disorders in transporters that keep substances in the bile and gallbladder. Certain types of the condition may be associated with symptoms during infancy or it may be manifested by cholestasis of pregnancy at young age. The most common symptoms include jaundice, diarrhea, developmental delay, hepatic hemorrhage secondary to increased pressure, intraabdominal fluid accumulation and itching. Itching may be considered allergy and the patient may wrongly be diagnosed with eczema. In some cases, liver failure requiring liver transplantation and cirrhosis may develop. In such cases, different medications are used, but the course of the disease may be different depending on the type. For these patients, all necessary diagnostic and therapeutic procedures including liver transplantation can be performed at our Pediatric Liver Diseases Outpatient Settings. Also, researches regarding new treatment methods are ongoing at our Pediatric Liver Transplantation Outpatient Settings.
Portal Vein Thrombosis and Variceal Hemorrhage
Liver diseases or varicose veins in the esophagus and colon caused by clot formations in the hepatic veins may result in life-threatening bleedings. At our unit, the underlying cause of such bleedings is detected through Ultrasound, Tomography and Angiography and necessary treatment is provided.

Endoscopic procedures are carried out under supervision of pediatric anesthesiologists at our Endoscopic Diagnosis and Treatment Unit. Before the procedure, information and preparation processes are conducted by our coordinator.  After the procedure is completed, assessment is made by our doctors and family is informed, the patient is discharged. Such procedures can be performed under elective or emergency conditions for any age group. Endoscopy can be applied for diagnostic purposes or endoscopic treatments can also be done in the same session with prior information and consent of family.

Pediatric Endoscopic Procedures Performed at Endoscopic Diagnosis and Treatment Unit
  • Upper gastrointestinal endoscopy
  • Colonoscopy
  • Evaluation of varix and band ligation procedure
  • Evaluation and management of bleeding
  • Detection and removal of polyps
  • PEG
  • ERCP
  • Submucosal endoscopic myomectomy (POEM)
  • Endoultrasonography

For Which Diseases And Complaints Do Patients Present To Your Department?

  • Nausea-vomiting
  • Gastro-esophageal Reflux Disease
  • Achalasia
  • Gastritis / Helicobacter pylori gastritis
  • Swallowing disorders
  • Celiac disease
  • Food allergies
  • Lactose intolerance
  • Chronic diarrhea
  • Inflammatory bowel diseases
  • Eosinophilic gastrointestinal diseases
  • Motility disorders (constipation, fecal incontinence etc.)
  • Anorectal Diseases
  • Gastric-intestinal bleedings
  • Short bowel syndrome
  • Abdominal pain

  • Abnormalities identified on hepatic tests
  • Prolonged Jaundice
  • Neonatal cholestasis
  • Hereditary jaundices (PFIC, Alagille, ARC etc).
  • Metabolic liver diseases (Wilson Disease, Tyrosinemia, Mitochondrial diseases, hemochromatosis, NBAS…etc).
  • Bilirubin metabolism disorders (Crigler–Najjar syndrome…etc.)
  • Acute and Chronic Hepatitis
  • Autoimmune hepatitis
  • Primary sclerosing cholangitis
  • Primary biliary cirrhosis
  • Drug and toxin induced liver diseases (toxic hepatitis)
  • Hepatosteatosis (fat deposition in the liver)
  • Cirrhosis, portal hypertension
  • Acute liver failure and coma
  • Chronic liver disease.
  • Congenital and acquired abnormalities and disorders of the liver, gallbladder and bile ducts (biliary atresia, cholecdochus cyst, congenital hepatic fibrosis)
  • Hereditary and acquired pancreas diseases.
  • Pancreatitis
  • Cystic fibrosis

  • Nutrition of Well Child
  • Eating disorders
  • Swallowing disorders
  • Growth retardation
  • Obesity
  • Nutrition for specific clinical conditions

What Invasive Procedures Are Performed At Your Department And Motility Unit?

  • Esophagogastroduoenoscopy
  • Colonoscopy
  • Balloon dilatation
  • POEM
  • Polypectomy
  • Band ligation
  • 24-hour ph monitoring
  • Impedance and manometry
  • Endoultrasonography
  • ERCP
  • Fibroscan -elastography

*Projects conducted/completed by Division of Gastroenterology, Hepatology and Nutrition

  • FOCUS Wilson Study  - Phase 3 Clinical Study (Turkey Coordinator)
  • Changing the course of itch and liver diseases with Maraliximab in PFIC patients-MRX – Phase 3 Clinical study (Turkey Chief Coordinator)
  • International genetic cholestasis consortium database-NAPPED Study group
  • Alagille Syndrome international study group –GALA study group
  • Genetic cholestasis in Turkish children-TUSEB grant (2020-2 years)
  • Multi-centric Non-Pharmaceutical Screening Study Identifying The Incidence Rate of Duchenne Muscular Distrophy and Pompe Disease in Children With Unexplained Transaminase Elevation (Researcher)
  • TOLERUP – Prospective And Observational Study Evaluating The Safety And Effects Of Enteral Nutrition Product Containing Partially Hydrolyzed Protein And Medium-Chain Triglycerides On Gastrointestinal Symptoms İn Pediatric Cerebral Palsy Patients With Gastrointestinal Intolerance Symptoms, DA-15
  • Bregs in the monitoring of liver graft in paediatric liver transplantation -KOC University seeds funding (2019- 2 yrs)
  • Pediatric liver disease blood and tissue immune cell monitoring- TKAD (2019-2 yrs)

  • Disease course and treatment response of eosinophilic gastrointestinal diseases in children with liver transplantation: long-term follow-up. Elif Ozdogan, Latife Doganay, Demet Can, Cigdem Arikan. American J of Gastroenterology. 2020
  • Upper Gastrointestinal Bleeding as the First Presentation of Eosinophilic Gastrointestinal Disease. E Ozdogan, LD Caglayan, O Mizikoglu, C Arikan - JPGN Reports, 2020
  • Genotype correlates with the natural history of severe bile salt export pump deficiency. Daan B.E. van Wessel, Richard J. Thompson, Emmanuel Gonzales, Bettina E. Hansen, Cigdem Arikan, Henkjan J. Verkade. J Hepatol 2020 jul;73(1):84-93.
  • Immune monitoring of a child with autoimmune hepatitis and type 1 diabetes during COVID-19 infection.Yuksel M, Akturk H, Arikan C. Eur J Gastroenterol Hepatol. 2020 Sep;32(9):1251-1255.
  • Gastrointestinal perforations and associated risk factors in children after liver transplantation. Aslan S, Akış Yıldız Z, Yazar Ş, Kargı A, Dönmez R, Selimoğlu A, Arıkan Ç, Kavlak E, Polat KY.Pediatr Transplant. 2020 Nov 5:e13911. doi: 10.1111/petr.13911. 
  • Hepatocellular Carcinoma and Liver Transplantation: A Single-Center Experience. Polat KY, Acar S, Gencdal G, Yazar S, Kargi A, Donmez R, Aslan S, Kavlak ME, Arikan C, Akyildiz M. Transplant Proc. 2020 Jan-Feb;52(1):259-264. doi: 10.1016/j.transproceed.2019.10.029. Epub 2020 Jan 3. Mutlu GY, Taşdemir M, Kızılkan NU, Güran T, Hatun Ş, Kayserili H, Bilge I.
  • A rare cause of chronic hyponatremia in an infant: Answers. Pediatr Nephrol. 2019 Aug 19. doi: 10.1007/s00467-019-04337-0. [Epub ahead of print] PubMed PMID: 31428928.   Mutlu GY, Taşdemir M, Kızılkan NU, Güran T, Hatun Ş, Kayserili H, Bilge I.
  • A rare cause of chronic hyponatremia in an infant: Questions. Pediatr Nephrol. 2019 Aug 19. doi: 10.1007/s00467-019-04335-2. [Epub ahead of print] PubMed PMID: 31428927.   Acar S, Kavlak ME, Demir B, Ozkan P, Polat KY, Akyildiz M, Arikan C.
  • Posterior Reversible Encephalopathy Syndrome in a Five-Year-Old Child: A Case Report. Transplant Proc. 2019 Sep;51(7):2495-2497. doi: 10.1016/j.transproceed.2019.01.186. Epub 2019 Jul 24. PubMed PMID: 31351771.  Yesilbas O, Sevketoglu E, Petmezci MT, Kihtir HS, Benzer M, Arikan C, Berdeli  A, Baloglu H, Baskan O.
  • Infant onset severe complement-mediated hemolytic uremic  syndrome complicated by secondary sclerosing cholangitis. J Clin Apher. 2018 Oct;33(5):619-623. doi: 10.1002/jca.21651. Epub 2018 Aug 30. PubMed PMID: 30168181. Yazici MU, Cil B, Bayrakci B, Sasmaz N, Baysoy G, Gurakan F.
  • Transarterial and Transhepatic Endovascular Intervention to Alleviate Portal Hypertension Secondary to Arterioportal Fistula in a Trisomy 21 Infant. J Pediatr Intensive Care. 2018 Mar;7(1):54-58. doi: 10.1055/s-0037-1603822. Epub 2017 Jun 21. PubMed PMID: 31073469; PubMed Central PMCID: PMC6260331.  Akman S, Şahaloğlu Ö, Dalkan C, Bahçeciler NN, Arıkan Ç.
  • Is celiac disease misdiagnosed in children with functional constipation? Turk J Gastroenterol. 2018 Mar;29(2):210-214. doi: 10.5152/tjg.2018.17369. PubMed PMID: 29749329; PubMed Central PMCID: PMC6284708.  Bicak DA, Urgancı N, Akyuz S, Usta M, Kizilkan NU, Alev B, Yarat A.
  • Clinical Evaluation of dental enamel defects and oral findings in coeliac disease. Eur Oral Res 2018; 52 (3):150-6. Gumus E, Haliloglu G, Karhan AN, Demir H, Gurakan F, Topcu M, Yuce A.
  • Niemann-Pick disease type C in the newborn period: a single-center experience. Eur J Pediatr. 2017 Dec;176(12):1669-1676. doi: 10.1007/s00431-017-3020-y. Epub 2017 Sep 27. PubMed PMID: 28951965.   Yilmaz C, Onen Z, Farajov R, Duygu OS, Doganay L, Yuksel A, Alper M, Zeytunlu  M, Arikan C, Kilic M.
  • Live donor liver transplantation for a child presented with severe hepatopulmonary syndrome and nodular liver lesions due to Abernethy malformation. Pediatr Transplant. 2017 Mar;21(2). doi: 10.1111/petr.12874. Epub 2017 Jan 12. PubMed PMID: 28078819.   Ozdogan S, Urgancı N, Usta M, Uslu Kızılkan N.
  • Prevalence of asthma and allergic rhinitis in children with Celiac disease. Iran J Pediatr (In Press):e6358  doi:10.5812/ijp.6358 (2016)-Clinical presentation in a series of eight children with abdominal tuberculosis: Experience of a single center in Turkey: Iran J Pediatr 2017: 72: Aydemir Y, Gürakan F, Saltık Temizel İN, Demir H, Oğuz KK, Yalnızoğlu D, Topçu M, Özen H, Yüce A.
  • Evaluation of central nervous system in patients with glycogen storage disease type 1a. Turk J Pediatr. 2016;58(1):12-18. PubMed PMID: 27922231.   Hizli Ş, Işikay S, Arikan Ç.
  • Ecthyma gangrenosum in an infant after liver transplantation. Pediatr Int. 2016 Sep;58(9):950-2. doi: 10.1111/ped.13066. PubMed PMID: 27682614.  Scott EM, Halees A, Itan Y, Spencer EG, He Y, Azab MA, Gabriel SB, Belkadi A,  Boisson B, Abel L, Clark AG; Greater Middle East Variome Consortium, Alkuraya FS, Casanova JL, Gleeson JG.
  • Characterization of Greater Middle Eastern genetic variation for enhanced disease gene discovery. Nat Genet. 2016 Sep;48(9):1071-6.  doi: 10.1038/ng.3592. Epub 2016 Jul 18. PubMed PMID: 27428751; PubMed Central PMCID: PMC5019950.   Belkadi A, Pedergnana V, Cobat A, Itan Y, Vincent QB, Abhyankar A, Shang L, El Baghdadi J, Bousfiha A; Exome/Array Consortium, Alcais A, Boisson B, Casanova JL, Abel L.
  • Whole-exome sequencing to analyze population structure, parental inbreeding, and familial linkage. Proc Natl Acad Sci U S A. 2016 Jun 14;113(24):6713-8. doi: 10.1073/pnas.1606460113. Epub 2016 May 31. PubMed PMID: 27247391; PubMed Central PMCID: PMC4914194.  Uslu Kızılkan N, Bozkurt MF, Saltık Temizel IN, Demir H, Yüce A, Caner B, Özen H.
  • Comparison of multichannel intraluminal impedance-pH monitoring and reflux scintigraphy in pediatric patients with suspected gastroesophageal reflux. World  J Gastroenterol. 2016 Nov 21;22(43):9595-9603. PubMed PMID: 27920480; PubMed Central PMCID: PMC5116603.  Balamtekin N, Aksoy Ç, Baysoy G, Uslu N, Demir H, Köksal G, Saltık-Temizel İN, Özen H, Gürakan F, Yüce A.
  • Is compliance with gluten-free diet sufficient? Diet composition of celiac patients. Turk J Pediatr. 2015 Jul-Aug;57(4):374-9. PubMed  PMID: 27186700. Kansu A, Kuloğlu Z, Demir A, Yaman A; Turkish Celiac Study Group.
  • Yield of coeliac screening in abdominal pain-associated functional gastrointestinal system disorders. J Paediatr Child Health. 2015 Nov;51(11):1066-70. doi: 10.1111/jpc.12929. Epub 2015 Jun 3. PubMed PMID: 26041019.