[Serum macroamylase in a subject with non-Hodgkin's lymphoma]

Macroamylasemia (MA) is a rare condition characterized by an active macromolecular complex formed by normal amylase with abnormal proteins; to our knowledge, it has not been previously described in Mexico. The size of the macromolecular complex precludes its renal excretion; thus MA is characterized by high levels of amylase in serum with normal amylasuria. We report a 53-year-old male with abdominal pain and hyperamylasemia who was erroneously diagnosed as pancreatitis. Amylase in urine was normal and a protein electrophoresis demonstrated hyperglobulinemia. Several months after the initial work-up, the diagnosis of non-Hodgkin's lymphoma was established. Serum pancreatic amylase was again found elevated with normal urinary amylase. Precipitation of amylase with polyethylene-glycol was of 81% (normal: less than 70%). This established the diagnosis of MA associated to non-Hodgkin's lymphoma. After chemotherapy, the abnormal macroamylasemia and hyperglobulinemia disappeared.