PTH and Marchiafava-Bignami disease: Both screening and peak PTH concentrations were markedly elevated in the MBD group [29 pmol/L (SD 10.4) vs. 11 pmol/L (SD 4.2); p < 0.001 and 31.5 pmol/L (SD 15.5) vs. 14.2 pmol/L (SD 8.1); p < 0.001, respectively].