Background Cystic fibrosis (CF) is the most frequent monogenic autosomal recessive disease with lethal potential, manifested by a great clinical polymorphism. Cystic fibrosis associated liver disease(CFLD) is the second non-pulmonary cause of death in cystic fibrosis, witch, beside pulmonary disease, became on of the most important management issue. Lung function and CFLD is influenced by the nutritional status, being well known that a positive correlation between increase body mass index (BMI) and respiratory disease exists; therefore the effect of the nutritional grade would be important to be assessed.

Objectives The aim of this study is to evaluate the effect of the nutritional status on the cystic fibrosis associated liver disease-CFLD evolution.

Methods Study included fifty-nine patients with cystic fibrosis prospectively monitored for seven years. They were routinely followed-up by clinical assessment, liver biochemical tests, ultrasound examinations and in several cases elastography. CFLD was diagnosed using ECFS criteria. All patients with CFLD received ursodeoxycholic acid and enzymes supplementation according to our guideline. Body mass index was used to evaluate the nutritional status expressed by percentages and z -scores.

Results 62.7% were diagnosed with CFLD and weight deficit, without significant gender gap. About 7% of patients leave the study. Underweighted children associated various vitamins deficiency and the reduced BMI was a significant risk factor for the development of CF severe liver disease (p<0.01). Severe CFLD, with portal hypertension was frequent in underweight children, in a 81.06% of patients/

Conclusion Most of our children with cystic fibrosis liver disease associated an important percent of weight deficit. If the malabsorbtion is the main cause of poor nutritional status or if other features like CF liver disease are more important remain to be studied in the future. The eternal question of’ the egg or hen’ as CFLD associates low BMI or if the weight deficit determine the CFLD rate is still disputable. Further measures should be taken for the improvement of nutrition of the CF children and the prolongation of a good life for these cystic fibrosis children.