Vitamin K status in cystic fibrosis

Abstract

Appearance of PIVKA-II (protein induced by vitamin K absence-II) in serum is a biochemical sign of insufficient vitamin K-dependent carboxylation of prothrombin. Plasma concentrations of PIVKA-II and vitamin K1 were determined in 24 children with cystic fibrosis. Eight were supplemented with vitamin K1. The purpose of the study was to determine the occurrence of vitamin K deficiency in cystic fibrosis and to evaluate the effect of vitamin K supplementation. PIVKA-II was detectable in only one unsupplemented child. In this patient, the concentration of vitamin K1 was below the limit of detection of 60 ng/l. Vitamin K1 levels in the other unsupplemented children were normal (mean 476 ng/l = 1 mmol/l). The supplemented patients showed extremely high levels of vitamin K1 (mean 22445 ng/l = 50 nmol/l). In conclusion, vitamin K deficiency occurs infrequently in cystic fibrosis. Checking the coagulation system is advised, but routine vitamin K supplementation is not recommended. If additional vitamin K is needed, the starting dose should not exceed 1 mg daily.

Prevalence of vitamin K deficiency in cystic fibrosis

“…One of the drawbacks of these earlier studies was their small sample sizes (24-43 patients), which makes it difficult to assess the risk factors for vitamin K deficiency (severity of steatorrhea, antibiotic use, and presence of liver disease). Furthermore, in some studies, data from supplemented and unsupplemented patients were combined (12,13). Moreover, the differences in results could also have been due to the variation in the laboratory tests used to assess vitamin K deficiency (9).…”

Vitamin K Status Among Children With Cystic Fibrosis and Its Relationship to Bone Mineral Density and Bone Turnover

“…13 Routine vitamin K administration at birth removes this risk. 14 Early studies of vitamin K status among older children and young adults with CF yielded conflicting results, documenting adequate vitamin K levels for most patients 15,16 but also vitamin K-associated coagulopathy 17 and increased PIVKA-II levels. 18 Fiftysix of 128 patients (44%) in those 4 studies 15-18 were receiving vitamin K supplements.…”

Vitamin K supplementation for cystic fibrosis

“…The review authors discussed the eligibility of these trials, resolved any remaining uncertainties by consensus. Two trials were included (Beker 1997; Drury 2008), five trials were excluded (Cornelissen 1992; Grey 2008; Mosler 2003; Nicolaidou 2006; Wilson 2001), and two trials are awaiting classification until we obtain further information from the trialists (van Hoorn 2003; van Hoorn 2008) and remain in the same category during the time for update.…”