Serum alpha-amylase isozymes in mumps: estimation of salivary and pancreatic isozymes by isoelectric focusing.

Serum alpha-amylase isozymes were separated into three major isozymes by thin-layer gel isoelectric focusing and detected by a starch-iodine zymogram procedure. Of the three groups of isozymes, one (S isozyme) corresponded to a salivary specific form, one (P isozyme) to a pancreatic specific form and the third (SP isozyme) to isozymes of similar isoelectric point common to both secretions. The levels of total alpha-amylase and of these three isozymes were estimated in the sera of 54 patients with mumps. Total alpha-amylase and salivary isozyme concentrations were greatly increased in the sera of all patients compared with controls. Pancreatic isozyme concentrations however, were only slightly increased and did not correlate with clinical pancreatitis. Indeed, in patients with mumps associated with pancreatitis, meningoencephalitis or orchitis, levels of total serum amylase, although higher than controls, were lower than levels in patients who presented solely with mumps sialadenitis.