In recent years, dozen of studies have demonstrated that the prevalence of vitamin D deficiency (VDD) among critically-ill children at admission to pediatric intensive care unit (PICU) was in range of 25%-84% [1-5]. Few of these demonstrated that VDD was associated with greater severity of illness and longer PICU stay [1-3].

We read with interest the research article on the topic by Shah, et al. [5]. Authors demonstrated a high prevalence of VDD (83.1%) among 154 critically-ill children. They noted no differences in severity of illness at admission, mortality, and duration of PICU stay among vitamin D-deficient and non-deficient children. The high prevalence of VDD in this study cohort could be due to high prevalence of malnutrition (65.6%) and presence of chronic illness (55.4%), which directly or indirectly could have influenced vitamin D status. It could have been better if authors had included matched controls to account for the baseline prevalence of VDD in the given population.

Recently, we demonstrated that the prevalence of VDD (level <20 ng/mL) among 124 critically-ill children with sepsis and 338 healthy controls was 50.8% and 40.2%, respectively (P=0.04) [4]. We also noted that the severity of illness assessed by PRISM III and SOFA scores was not significantly different between cases with VDD and those with non-deficient levels of vitamin D, though the PRISM III score was slightly higher in cases with VDD. Also, there was a trend toward increased occurrence of septic shock and MODS, requirement for catecholamines and mechanical ventilation, development of healthcare associated infections, and occurrence of hypocalcemia in cases with VDD; though the difference was not statistically significant. Whereas Shah, et al. [5] noted lower mortality, shorter PICU stay, lesser requirement and duration of mechanical ventilation, and lesser incidence of ARDS in vitamin D-deficient cases. This was in contrast to previous studies [1-4]. Shah, et al. [5] mistakenly mentioned non-vitamin D deficient children as 19.8% in abstract section, which should be 16.9%.

Larger multicentric studies are needed to determine the prevalence of VDD, association of VDD with clinically important outcomes, and effect of supplementation of vitamin D in critically-ill children. Till then, it is important for critical care physicians to carefully examine the results of available studies before clinical applicability.

Acknowledgement: Dr Renu Suthar for providing intellectual inputs and critically reviewing manuscript.

1. Madden K, Feldman HA, Smith EM, Gordon CM, Keisling SM, Sullivan RM, et al. Vitamin D deficiency in critically ill children. Pediatrcs. 2012;130:421-8.

2. McNally JD, Menon K, Chakraborty P, Fisher L, Williams KA, Al-Dirbashi OY, et al. The association of vitamin D status with pediatric critical illness. Pediatrics. 2012;130: 429-36.

3. Ebenezer K, Job V, Antonisamy B, Dawodu A, Manivachagan MN, Steinhoff M. Serum vitamin D status and outcome among critically ill children admitted to the pediatric intensive care unit in south India. Indian J Pediatr. 2015;83:120-5.

4. Ponnarmeni S, Kumar Angurana S, Singhi S, Bansal A, Dayal D, Kaur R, et al. Vitamin D deficiency in critically ill children with sepsis. Paediatr Int Child Health. 2016;36:15-21.

5. Shah SK, Kabra SK, Gupta N, Pai G, Lodha R. Vitamin D deficiency and parathyroid response in critically-ill children: association with illness severity and clinical outcomes. Indian Pediatr. 2016;53:479-84.