Introduction. Cystic fibrosis (CF) patients are at risk of developing vitamin K deficiency. However, there is no clinical data clearly describing vitamin K status in the youngest age group. Therefore, in the present study we aimed to assess body resources of vitamin K in children aged up to 3 years and to correlate vitamin K status with selected clinical factors.
Material and methods. The study comprised 52 CF patients receiving and not receiving vitamin K supplementation. In all subjects, the concentration of the undercarboxylated prothrombin (PIVKA-II), as a marker of vitamin K deficiency, was determined.
Results. PIVKA-II concentrations were pathological in 24 (46.2%) CF children, in remaining 28 (53.8%) patients vitamin K status was found to be normal. No statistical differences in clinical parameters (Z-score for body height and weight, number of hospitalizations and sweat chloride concentrations) neither in distribution of Pseudomonas aeruginosa colonization nor in pancreatic status between selected subgroups with normal and abnormal PIVKA-II concentrations were documented. Normal vitamin K status was more frequent in patients receiving proper vitamin K supplementation (p < 0.0078). However, vitamin K deficiency appeared in 5 out of 21 patients receiving at least 2.5 mg vitamin K/week. In logistic regression model, no clinical parameter was proven to be a risk factor for vitamin K deficiency.
Conclusion. Vitamin K deficiency is frequent in CF infants and toddlers, and may also appear in those receiving recommended supplementation. There is no strong relationship between clinical expression of the disease and vitamin K status.