- Teichmann J, Mann S, Stracke H, Lange U, Hardt P, Bretzel R, et al. Parathormone levels and Vitamin D metabolism in female patients with various grades of fecal elastase 1 deficiency. Eur J Med Res. 2008;13:563-7 pubmed..There seems to be a connection here between the loss of exocrine function and may be even the characteristic of sterol-binding of elastase 1 in the pancreas, which seems to be relevant for vitamin D-supply. ..