Prevalence and treatment of vitamin K deficiency in paediatric patients with recessive dystrophic epidermolysis bullosa‐severe subtype

INTRODUCTION: Patients with recessive dystrophic epidermolysis bullosa‐severe subtype (RDEB‐S) are at risk of vitamin K deficiency, potentially causing abnormal clotting, excessive bleeding, poor bone metabolism and abnormal vascular calcification. This study quantifies vitamin K deficiency prevalence in this cohort and identifies potential risk‐factors to prevent deficiency. METHODS: Patients with RDEB‐S who attended the EB service between 2014 and 2020 were included. Serum vitamin K and PIVKAII were measured as part of the usual nutritional blood screen. Dietetic and medical notes were reviewed to establish: antibiotic use, enteral feed intake and micronutrient supplementation. RESULTS: A total of 16/25 64% (10/16 female), of children aged 22–180 months, had serum vitamin K and PIVKAII analysed. Six of sixteen (37.5%) patients had vitamin K deficiency requiring supplementation. Two of six (33.3%) normalized serum vitamin K after 12 weeks supplementation with oral menadiol diphosphate. Four of six (66.6%) await retesting following supplementation. Six of six (100%) patients with vitamin K deficiency were not consuming a gastrostomy/sip feed. Nine of ten (90%) patients with sufficient vitamin K levels were consuming either; more than 200 ml prescribed sip feed or more than 400–800 ml gastrostomy feed daily (containing 5.9–11 µg/100 ml vitamin K). Patients who were consuming either more than 200 ml prescribed sip feed or more than 400–800 ml gastrostomy feed daily (containing 5.9–11 µg/100 ml vitamin K) were significantly less likely to suffer from vitamin K deficiency (0.08 odds ratio [(1/7)/(5/3)] with significance level p = 0.0342 [95% CI: 0.0074–0.8275]). Sixteen of sixteen (100%) received antibiotics (range 0–4 courses/year; median, 3; IQR, 3). Patients with the most frequent antibiotics (n = 4) had normal vitamin K and PIVKAII levels if they consumed a minimum of 200 ml prescribed sip feed or 400–800 ml gastrostomy feed daily. Sixteen of sixteen (100%) patients took a multivitamin/mineral supplement; none contained vitamin K. SUMMARY: The prevalence of vitamin K deficiency is 37.5% in this cohort. Patients whom were not consuming gastrostomy/sip feeds of at least 200 ml daily were at greatest risk of vitamin K deficiency. Patients on a micronutrient supplement remain at risk of vitamin K deficiency, as most contain no vitamin K. Prescribing a vitamin/mineral supplement that contains vitamin K is recommended. Twelve‐week supplementation of oral vitamin K (5 mg/day for 1–10 years and 10 mg/day for 12–17 years) adequately improved stores.