muramidase and Thoracic-Neoplasms

We studied the value of serum lysozyme as a helpful test in distinguising tuberculous involvement of intrathoracic glands from lymphoma. Nineteen of the 28 patients (all Asian immigrants) with intrathoracic glandular tuberculosis had raised serum lysozyme level as compared with 2 of the 29 patients with lymphoma. While a normal serum lysozyme level is unhelpful, a raised level in an Asian immigrant with hilar or mediastinal lymphadenopathy makes tuberculosis a highly probable diagnosis.

Topics: Africa, Eastern; Bronchial Neoplasms; Clinical Enzyme Tests; Diagnosis, Differential; Female; Humans; India; Lymphatic Diseases; Lymphoma; Male; Muramidase; Sarcoidosis; Thoracic Neoplasms; Tuberculosis, Lymph Node; Tuberculosis, Pulmonary; Wales

Serum angiotensin-converting enzyme (ACE) activity was studied in healthy controls, in 57 untreated sarcoidosis patients, and in 164 patients with other chest or lymph node diseases. The serum ACE activity of healthy persons was independent of sex, intake of meals, and smoking habits. There were no diurnal variations. Healthy children had a significantly higher ACE mean value than adults, whose ACE activity was not affected by age. The sarcoidosis patients had the highest ACE mean values, but those of patients with silicosis and asbestosis were also significantly elevated. Pulmonary cancer patients had decreased serum ACE activity, which was probably due to antimitotic treatment. Serum lysozyme (LZM) concentrations did not correlate with normal ACE activity, but the correlation between elevated ACE and LZM was significant in sarcoidosis and silicosis, and the trend was clearly the same for asbestosis. This indicates separate sources for these enzymes when ACE activity is normal, and a common source, i.e. macrophages, when ACE activity is increased. ACE production in certain diseases involving macrophages may be due to the bradykinin inhibiting effect of this enzyme.

Topics: Adolescent; Adult; Alveolitis, Extrinsic Allergic; Asbestosis; Bronchitis; Female; Hodgkin Disease; Humans; Lung Diseases; Lung Neoplasms; Lymphatic Diseases; Lymphoma; Male; Middle Aged; Muramidase; Peptidyl-Dipeptidase A; Pneumonia; Pulmonary Fibrosis; Sarcoidosis; Silicosis; Thoracic Neoplasms; Tuberculosis, Lymph Node; Tuberculosis, Pulmonary