Vitamin D and metabolic bone disease in prolonged continuous kidney replacement therapy: a prospective observational study.

BACKGROUND

Complications of prolonged continuous kidney replacement therapy (CKRT) have not been well described. Our objective was to describe mineral metabolism and bone findings in children who required prolonged CKRT.

METHODS

In this single center prospective observational study, we enrolled 37 patients who required CKRT for ≥ 28 days with regional citrate anticoagulation. Exposure was duration on CKRT and outcomes were 25-hydroxy vitamin D and osteopenia and/or fractures.

RESULTS

The prevalence of vitamin D deficiency and insufficiency was 17.2% and 69.0%, respectively. 29.7% of patients had radiographic findings of osteopenia and/or fractures. There was no association between vitamin D deficiency or insufficiency with age or ethnicity. Time on CKRT and intact PTH levels were not predictive of vitamin D levels. Children with chronic liver disease were more likely to have osteopenia and/or fractures compared children with other primary diagnoses, odds ratio (3.99 (95%CI, 1.58-2.91), p = 0.003) after adjusting for age and time on CKRT.

CONCLUSION

Vitamin D deficiency and/or insufficiency, and osteopenia and/or fractures are prevalent among children who require CKRT for a prolonged period. The risk for MBD may be higher with chronic liver disease. Higher doses of vitamin D may be required to maintain normal levels while on CKRT.