Echis time, under-carboxylated prothrombin and vitamin K status in intensive care patients

Vitamin K insufficiency and the prophylaxis strategy in term healthy infants: A multicentre study

BACKGROUND/AIM

Late vitamin K deficiency bleeding (VKDB) during early infancy is a serious problem worldwide. Vitamin K (VK) deficiency commonly occurs in newborns who are exclusively breastfed. Protein Induced by VK Absence (PIVKA-II) has been identified as an early indicator of subclinical VK deficiency in neonates, surpassing prothrombin time. To assess PIVKA-II levels at 48 h, 1 and 3 months of age in full-term newborns who were exclusively breastfed and received varying VKDB prophylaxis regimens.

METHODS

A prospective observational study was conducted in four hospitals, enrolling 105 newborns. PIVKA-II levels were measured using a sandwich-type enzyme-linked immunosorbent assay.

RESULTS

At 48 h of age, there was no significant difference in PIVKA-II concentrations between newborns who received intramuscular administration of 1 mg of phylloquinone (VK1) and those who received oral administration of 2 mg of VK1 at birth. At 1 and 3 months of life, infants who received any supplementation regimen between 2 and 14 weeks exhibited significantly lower PIVKA-II concentrations compared to infants who received only 1 mg of intramuscular VK1 at birth. The prophylaxis involving a dose of 1 mg of intramuscular VK1 at birth followed by oral administration of 150 μg/day of VK1 from the 2nd to the 14th week of life showed the lowest PIVKA-II blood concentrations.

CONCLUSIONS

Oral supplementation of VK1 after discharge significantly reduced PIVKA-II concentrations in exclusively breastfed term infants. These findings suggest the importance of oral VK1 supplementation in exclusively breastfed infants during their first 3 months of life to avoid the risk of VK insufficiency.

Three Different Regimens for Vitamin K Birth Prophylaxis in Infants Born Preterm: A Randomized Clinical Trial

OBJECTIVE

To study the efficacy of 3 different vitamin K birth prophylaxis regimens in infants born premature.

STUDY DESIGN

This was an open-label, parallel-group, randomized clinical trial conducted in a tertiary neonatal care unit in India. Infants born very preterm (≤32 weeks) and/or with very low birth weight (≤1500 g) were included. In each arm, 25 babies were enrolled. Babies were randomized to receive 1.0 mg, 0.5 mg, or 0.3 mg intramuscular (IM) vitamin K1 at birth. Protein induced by vitamin K absence - II (PIVKA-II) levels were assessed at birth, and on days 5 and 28, along with the frequency of death, bleeding manifestations, intraventricular hemorrhage, necrotizing enterocolitis, bilirubin levels, and duration of phototherapy. The primary outcome was comparison of PIVKA-II levels on day 5 of life.

RESULTS

All the 3 regimens resulted in similar proportion of vitamin K subclinical sufficiency (PIVKA-II < 0.028 AU/mL) infants on day 5 (1 mg - 100%; 0.5 mg - 91.7%; 0.3 mg - 91.7%, P = .347), with no significant difference in median (IQR) PIVKA-II levels (AU/mL): 1 mg 0.006 (0.004, 0.009); 0.5 mg 0.008 (0.004, 0.009); 0.3 mg 0.006 (0.003, 0.009), P = .301. However, on day 28, there was a significant decrease in the proportion of vitamin K-sufficient infants in the 0.3-mg IM group (72.7%) compared with the 1.0-mg (100%) or 0.5-mg (91.3) groups. The 1.0-mg group had significantly greater bilirubin levels and duration of phototherapy. None of the other clinical outcomes were statistically different.

CONCLUSIONS

Both 1-mg and 0.5-mg IM vitamin K birth prophylaxis resulted in high sufficiency on follow-up, compared with 0.3 mg. The current recommendation of 0.5-1 mg IM vitamin K birth prophylaxis for infants born preterm, needs to be continued.

TRIAL REGISTRATION

CTRI/2022/02/040396.

Trends of INR and Fecal Excretion of Vitamin K During Cholestasis Reversal: Implications in the Treatment of Neonates With Intestinal Failure-Associated Liver Disease

BACKGROUND

Vitamin K is a fat-soluble compound that plays important roles in coagulation. In children with intestinal failure-associated liver disease (IFALD), the disrupted enterohepatic circulation can lead to intestinal loss of vitamin K. Fish oil-based lipid emulsion (FOLE) has proven effective in treating IFALD. As biliary excretion is restored during cholestasis reversal, the accelerated vitamin K loss can pose a risk for deficiency.

METHODS

Ten neonates with IFALD and receiving FOLE monotherapy were prospectively enrolled in the study from 2016 to 2018. In addition to weekly measurements of international normalized ratio (INR) and direct bilirubin (DB), ostomy output was collected for determination of fecal concentrations of phylloquinone (PK). Trends of DB, INR, and fecal PK concentrations were summarized with locally estimated scatterplot smoothing.

RESULTS

The median time (interquartile range) from FOLE initiation to cholestasis reversal was 59 (19-78) days. During cholestasis reversal, INR remained relatively unchanged, whereas the mean (95% confidence interval) daily fecal excretion of PK increased from 25.1 (5.0-158.5) ng at the time of FOLE initiation to 158.5 (31.6-1000.0) ng at complete reversal. Examination of individual trends in fecal PK excretion and INR revealed little correlation between the 2 measurements (r = -0.10; P = 0.50).

CONCLUSION

Children with IFALD are at risk for vitamin K deficiency during cholestasis reversal. Close monitoring and quantified supplementation of vitamin K may be warranted during this period. However, this should not be guided by INR alone, as it is a poor indicator of vitamin K status.

Prophylactic vitamin K for the prevention of vitamin K deficiency bleeding in preterm neonates

BACKGROUND

Vitamin K is necessary for the synthesis of coagulation factors. Term infants, especially those who are exclusively breast fed, are deficient in vitamin K and consequently may have vitamin K deficiency bleeding (VKDB). Preterm infants are potentially at greater risk for VKDB because of delayed feeding and subsequent delay in the colonization of their gastrointestinal system with vitamin K producing microflora, as well as immature hepatic and hemostatic function.  OBJECTIVES: To determine the effect of vitamin K prophylaxis in the prevention of vitamin K deficiency bleeding (VKDB) in preterm infants.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2016, Issue 11), MEDLINE via PubMed (1966 to 5 December 2016), Embase (1980 to 5 December 2016), and CINAHL (1982 to 5 December 2016). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles.

SELECTION CRITERIA

Randomized controlled trials (RCTs) or quasi-RCTs of any preparation of vitamin K given to preterm infants.

DATA COLLECTION AND ANALYSIS

We evaluated potential studies and extracted data in accordance with the recommendations of Cochrane Neonatal.

MAIN RESULTS

We did not identify any eligible studies that compared vitamin K to no treatment.One study compared intravenous (IV) to intramuscular (IM) administration of vitamin K and compared various dosages of vitamin K. Three different prophylactic regimes of vitamin K (0.5 mg IM, 0.2 mg vitamin K₁, or 0.2 mg IV) were given to infants less than 32 weeks' gestation. Given that only one small study met the inclusion criteria, we assessed the quality of the evidence for the outcomes evaluated as low.Intramuscular versus intravenousThere was no statistically significant difference in vitamin K levels in the 0.2 mg IV group when compared to the infants that received either 0.2 or 0.5 mg vitamin K IM (control) on day 5. By day 25, vitamin K₁ levels had declined in all of the groups, but infants who received 0.5 mg vitamin K IM had higher levels of vitamin K₁ than either the 0.2 mg IV group or the 0.2 mg IM group.Vitamin K₁ 2,3-epoxide (vitamin K₁O) levels in the infants that received 0.2 mg IV were not statistically different from those in the control group on day 5 or 25 of the study. All of the infants had normal or supraphysiologic levels of vitamin K₁ concentrations and either no detectable or insignificant amounts of prothrombin induced by vitamin K absence-II (PIVKA II).Dosage comparisonsDay 5 vitamin K₁ levels and vitamin K₁O levels were significantly lower in the 0.2 mg IM group when compared to the 0.5 mg IM group. On day 25, vitamin K₁O levels and vitamin K₁ levels in the 0.2 mg IM group and the 0.5 mg IM group were not significantly different. Presence of PIVKA II proteins in the 0.2 mg IM group versus the 0.5 mg IM group was not significantly different at day 5 or 25 of the study.

AUTHORS' CONCLUSIONS

Preterm infants have low levels of vitamin K and develop detectable PIVKA proteins during the first week of life. Despite being at risk for VKDB, there are no studies comparing vitamin K versus non-treatment and few studies that address potential dosing strategies for effective treatment. Dosage studies suggest that we are currently giving doses of vitamin K to preterm infants that lead to supraphysiologic levels. Because of current uncertainty, clinicians will have to extrapolate data from term infants to preterm infants. Since there is no available evidence that vitamin K is harmful or ineffective and since vitamin K is an inexpensive drug, it seems prudent to follow the recommendations of expert bodies and give vitamin K to preterm infants. However, further research on appropriate dose and route of administration is warranted.

PIVKA-II correlates with INR but not protein C or protein S concentrations in cord blood among newborns

BACKGROUND

Protein induced by vitamin K absence (PIVKA)-II, inactive precursor of prothrombin, is elevated in vitamin K (VK) deficiency. Our aims were to find the prevalence of VK deficiency in neonates, assess the utility of international normalized ratio (INR) as a screening tool, and explore the relationship between PIVKA-II, activated partial thromboplastin time (aPTT) and VK dependent anticoagulants.

METHODS

INR, aPTT, PIVKA-II, and proteins C and S activities were measured in neonatal cord blood prior to VK administration.

RESULTS

We found 45% of neonates had subclinical VK deficiency based on PIVKA-II levels and 7% based on INR. Receiver operating characteristic (ROC) analysis assessed the utility of INR in detecting >4 ng/mL of PIVKA-II and ROC of the area under the curve was 0.70 (95% CI 0.46-0.92, p = 0.07). Proteins C and S activities were normal for age and did not correlate with PIVKA-II [(r = 0.40, p = 0.14) and (r = 0.29, p = 0.29), respectively]. There was no association between aPTT and PIVKA-II (p = 0.83).

CONCLUSION

PIVKA-II seems to be a sensitive indicator of mild VK deficiency. Further studies are needed to investigate the lack of relationship between PIVKA-II and functional protein C or S levels.

Prevalence and Predictors of Functional Vitamin K Insufficiency in Mothers and Newborns in Uganda

Vitamin K deficiency bleeding (VKDB) in infancy is a serious but preventable cause of mortality or permanent disability. Lack of epidemiologic data for VKDB in sub-Saharan Africa hinders development and implementation of effective prevention strategies. We used convenience sampling to consecutively enroll mothers delivering in a southwestern Uganda Hospital. We collected socio-demographic and dietary information, and paired samples of maternal venous and neonatal cord blood for the immunoassay of undercarboxylated prothrombin (PIVKA-II), a sensitive marker of functional vitamin K (VK) insufficiency. We used univariable and multivariable logistic regression models to identify predictors of VK insufficiency. We detected PIVKA-II of ≥0.2 AU (Arbitrary Units per mL)/mL (indicative of VK insufficiency) in 33.3% (47/141) of mothers and 66% (93/141) of newborns. Importantly, 22% of babies had PIVKA-II concentrations ≥5.0 AU/mL, likely to be associated with abnormal coagulation indices. We found no significant predictors of newborn VK insufficiency, including infant weight (AOR (adjusted odds ratio) 1.85, 95% CI (confidence interval) 0.15–22.49), gender (AOR 0.54, 95% CI 0.26–1.11), term birth (AOR 0.72, 95% CI 0.20–2.62), maternal VK-rich diet (AOR 1.13, 95% CI 0.55–2.35) or maternal VK insufficiency (AOR 0.99, 95% CI 0.47–2.10). VK insufficiency is common among mothers and newborn babies in southwestern Uganda, which in one fifth of babies nears overt deficiency. Lack of identifiable predictors of newborn VK insufficiency support strategies for universal VK prophylaxis to newborns to prevent VKDB.

Effect of phylloquinone (vitamin K1) supplementation for 12 months on the indices of vitamin K status and bone health in adult patients with Crohn's disease

Although epidemiological findings support a role for vitamin K status in the improvement of bone indices in adult patients with Crohn's disease (CD), this needs to be confirmed in double-blind, randomised controlled trials (RCT) with phylloquinone (vitamin K1). By conducting two RCT, the present study aimed to first establish whether supplementation with 1000 μg of phylloquinone daily near-maximally suppresses the percentage of undercarboxylated osteocalcin in serum (%ucOC; marker of vitamin K status) in adult patients with CD currently in remission as it does in healthy adults and second determine the effect of supplementation with phylloquinone at this dose for 12 months on the indices of bone turnover and bone mass. The initial dose-ranging RCT was conducted in adult patients with CD (n 10 per group) using 0 (placebo), 1000 or 2000 μg of phylloquinone daily for 2 weeks. In the main RCT, the effect of placebo v. 1000 μg vitamin K/d (both co-administered with Ca (500 mg/d) and vitamin D3 (10 μg/d)) for 12 months (n 43 per group) on the biochemical indices of bone turnover (determined by enzyme immunoassay) and bone mass (determined by dual-energy X-ray absorptiometry) were investigated. At baseline, the mean %ucOC was 47 %, and this was suppressed upon supplementation with 1000 μg of phylloquinone daily ( - 81 %; P< 0·01) and not suppressed further by 2000 μg of phylloquinone daily. Compared with the placebo, supplementation with 1000 μg of phylloquinone daily for 12 months had no significant effect (P>0·1) on bone turnover markers or on the bone mass of the lumbar spine or femur, but modestly increased (P< 0·05) the bone mass of the total radius. Despite near maximal suppression of serum %ucOC, supplementation with 1000 μg of phylloquinone daily (with Ca and vitamin D3) had no effect on the indices of bone health in adult CD patients with likely vitamin K insufficiency.

Plasma phylloquinone (vitamin K1) concentration and its relationship to intake in British adults aged 19-64 years

Plasma phylloquinone (vitamin K1) concentration from non-fasted blood samples was examined by season, smoking status, socio-demographic factors and phylloquinone intake in a nationally representative sample of 1154 British individuals aged 19-64 years from the 2000-1 National Diet and Nutrition Survey. Geometric mean plasma phylloquinone concentration was 0.94 (95% CI 0.88, 1.00) nmol/l, with 95% of values in the range 0.10-8.72 nmol/l. Plasma phylloquinone concentrations of 530 men were significantly higher than those of 624 women (1.13 (95% CI 1.04, 1.22) v. 0.81 (95% CI 0.74, 0.88) nmol/l; P<0.001), independent of other factors. Women aged 19-34 years had significantly lower plasma phylloquinone concentration than their older counterparts. Women were also found to have lower plasma phylloquinone concentrations during summer compared with winter and spring (each P<0.01). In contrast, plasma phylloquinone concentration in men did not vary significantly by season or any of the socio-demographic or lifestyle factors. Plasma phylloquinone concentrations were positively correlated with phylloquinone intake in men and women (r 0.26 and 0.32 respectively; each P<0.001). Overall, forward stepwise multiple regression analysis revealed that 8% of the variation in plasma phylloquinone concentration was explained by phylloquinone intake, with a further 10% of its variation explained by plasma concentrations of gamma-tocopherol (6%) and retinyl palmitate (4%). After adjustment for age and corresponding nutrient intakes, plasma phylloquinone concentration was significantly associated (each P<0.01) with plasma concentrations of total and LDL-cholesterol, alpha- and gamma-tocopherols, retinyl palmitate, beta-carotene, lycopene and lutein plus zeaxanthin in men and women.

Vitamin K status among children with cystic fibrosis and its relationship to bone mineral density and bone turnover

OBJECTIVE

The aim of this study was to assess vitamin K status in an unselected population of children with cystic fibrosis (CF) and to investigate any vitamin K effect on bone turnover and bone mineral status.

METHODS

Children > or =5 years of age who were attending the CF unit were invited to enter the study. Fasting blood samples were analyzed for levels of vitamin K1 and prothrombin produced in vitamin K absence; total, undercarboxylated, and carboxylated osteocalcin (OC); and bone-specific alkaline phosphatase and procollagen I carboxy-terminal propeptide (bone formation markers). Levels of N-telopeptide and free pyridinoline and deoxypyridinoline (bone breakdown products) were measured in urine samples. Bone mineral density and bone mineral content were measured at the lumbar spine and for the total body with a GE Lunar Prodigy densitometer. Statistical analyses were performed with Minitab version 9.1.

RESULTS

One hundred six children entered the study. Sixty-five of 93 children (70%) from whom blood samples were obtained showed suboptimal vitamin K status, on the basis of low serum vitamin K1 levels, increased prothrombin produced in vitamin K absence levels, or both abnormalities. Vitamin K1 levels showed a significant negative correlation with undercarboxylated OC levels but showed no significant correlation with any marker of bone turnover or measurement of bone mineral status. Undercarboxylated OC levels were correlated significantly with bone turnover markers, which themselves showed a significant negative correlation with measurements of bone mineral density and content. There were no significant correlations between carboxylated or undercarboxylated OC levels and bone density measurements.

CONCLUSIONS

Vitamin K1 deficiency is common among children with CF, and routine supplements should be considered. Through its role in the carboxylation of OC, vitamin K deficiency may be associated with an uncoupling of the balance between bone resorption and bone formation. A cause-effect relationship between vitamin K deficiency and low bone mass has not been proved.

Pharmacokinetics and efficacy of oral versus intravenous mixed-micellar phylloquinone (vitamin K1) in severe acute liver disease

BACKGROUND/AIMS

In patients with severe acute liver dysfunction, i.v. phylloquinone (vitamin K1) may be given to exclude vitamin K deficiency, rather than impaired hepatic synthesis of coagulation factors alone, as the cause of the coagulopathy. However, there have been no studies of the pharmacokinetics or efficacy of i.v. or oral K1 in such patients.

METHODS

49 adults with severe acute liver disease were randomised double-blind to a single 10 mg dose of i.v. or oral mixed-micellar K(1), or placebo. Serum levels of phylloquinone and undercarboxylated prothrombin (PIVKA-II) were assessed before and after treatment.

RESULTS

At admission, 13 patients (27%) had either low serum K1 levels or elevated PIVKA-II concentrations, indicative of subclinical vitamin K deficiency. In the 16 patients who received i.v. K1, there was one (6%) treatment failure (K1 rise <10 ng/ml above baseline), compared with 12 of the 15 (80%) who received oral K1 (P<0.0001). One patient in the placebo group developed overt vitamin K deficiency.

CONCLUSIONS

A minority of patients with severe acute liver dysfunction have subclinical vitamin K deficiency at the time of presentation, which is corrected by a single dose of i.v. K1. The intestinal absorption of mixed-micellar K1 is unreliable in adults with severe acute liver dysfunction.