PTH and rickets: In this sense, it would be of interest to properly explore these findings in a population with SARS-CoV-2 infection, since remarkable prevalence of hypovitaminosis D has been observed in these patients [35, 38], characterizing, together with hypocalcemia and impaired PTH response, the osteo-metabolic phenotype recently described in these patients [7], as well as an inverse relationship between vitamin D levels and mortality for COVID-19 has been reported by several Authors from different countries, conferring to the question particular relevance [40–42].