(EN) The description relates to a process for obtaining a highly specific pancreas-elastasis-1-antibody which reacts with both bodily fluids and stools. Such an antibody is obtainable by immunisation with an antigen which has the amino acid sequence Thr-Met-Val-Ala-Gly-Asp-Ile-Arg or immunologically active partial peptides thereof. A test kit containing such antibodies is suitable for the diagnosis and monitoring of chronic and acute pancreatitis and mucoviscidosis in bodily fluids and/or stools.