Usefulness of Serum Lysozyme Measurement in Diagnosis and Evaluation of Sarcoidosis

LYSOZYME, a low-molecular-weight lysosomal enzyme, has limited antibacterial properties. Relatively high concentrations occur in polymorphonuclear leukocytes and monocytes,1 , 2 from which most of the enzyme probably derives.3 , 4 Assay of serum and urinary lysozyme is useful to distinguish myeloid and monocytic leukemias from lymphocytic leukemia.1 2 3 A slight to moderate increase in serum lysozyme activity occurs in patients with acute bacterial infections, leukemoid reactions, megaloblastic anemias, neutropenic disorders associated with increased granulocyte turnover and azotemia.3 , 5 6 7 In addition, lysozyme is frequently present in the urine when there is high serum activity or renal tubular damage.1 , 2 , 7 There are several reasons to suggest that serum lysozyme . . .