Abstract: A process is described for obtaining highly specific pancreas elastase 1 antibodies which react both with bodily fluids and with stools. Such an antibody is obtainable by immunizing with an antigen having the amino acid sequence Thr-Met-Val-Ala-Gly-Gly-Asp-Ile-Arg (SEQ ID NO:1) or immunologically active partial peptides thereof. A test kit containing such antibodies is suitable for the diagnosis and course monitoring of chronic and acute pancreatitis as well as mucoviscidosis in bodily fluids and/or in stools.