Salivary cortisol in the assessment of adrenocortical function in patients with pulmonary tuberculosis.

Adrenocortical function was assessed on the basis of changes in salivary cortisol in patients with pulmonary tuberculosis and the findings compared with those in healthy subjects. A method of direct radioimmunoassay of salivary cortisol was standardized and the sensitivity was 0.8 nmol/l. Cortisol levels in saliva were significantly higher in the patients than in the healthy subjects (P less than 0.001). The diurnal rhythm of cortisol secretion was disturbed in the patients with a significant increase in salivary cortisol beyond 1800 h. While dexamethasone caused an appreciable suppression (87%), stimulation with ACTH (tetracosactrin) resulted in a marked increase in salivary cortisol, the increase being significantly higher in the healthy subjects than in the patients (P less than 0.001). Attempts to classify subjects as positive or negative responders to tetracosactrin based on increases in salivary cortisol in relation to plasma cortisol changes were however not successful, as the agreement between the two methods ranged from 73 to 80 per cent with various criteria used.

Acute phase proteins in tuberculous patients.

The serum concentrations of some acute phase proteins were determined on admission, during treatment, at the end of treatment and at 12 months after stopping treatment in 20 patients with pulmonary tuberculosis. Measurements were also made, on admission and at the end of treatment, in 19 patients with abdominal tuberculosis, and 11 children with tuberculous meningitis. All 20 patients with pulmonary TB had quiescent disease by the end of treatment and none had a bacteriological relapse during the follow-up period of 12 months. The response to treatment was considered favourable in 18 of the 19 patients with abdominal TB, and the CSF findings had returned to normal in 9 of 11 patients with TB meningitis. There was a significant decrease with treatment in the concentrations of C-reactive protein, ceruloplasmin, haptoglobin and alpha-1-acid glycoprotein in all 3 groups of patients. While there was an increase in the concentrations of transferrin in patients with pulmonary and abdominal TB, there was a significant decrease in those with TB meningitis; alpha 2-macroglobulin did not appear to function as an acute phase reactant in any of the 3 groups. Amalgamating the findings in all 3 groups of tuberculous patients, the proportions of patients with abnormal values on admission and at the end of treatment were 62% and 14% for C-reactive protein, 78% and 50% for ceruloplasmin, 86% and 26% for haptoglobin and 92% and 6% for alpha 1-acid glycoprotein, respectively.

Induction of rifampicin metabolism during treatment of tuberculous patients with daily and fully intermittent regimens containing the drug.

Self-induction of rifampicin metabolism during daily and intermittent chemotherapy was studied by monitoring the changes in the serum half-life of the drug over a 4-week period in patients with pulmonary tuberculosis. Rifampicin 450 mg was administered to 8 patients who received treatment daily, 7 on thrice-weekly and 7 others on twice-weekly treatment. Serum half-life was computed from concentrations of the drug determined at 3, 4 1/2 and 6 hours after drug administration, on admission and at 1, 2 and 4 weeks after start of treatment. In the daily series, the mean serum half-life decreased from 4.9 hours on admission to 3.6 hours at 1 week (P = 0.02), and treatment beyond this had no further effect. In the thrice-weekly series, maximal induction was observed at the 2nd week, the mean values on admission and at 2 weeks being 5.8 and 3.7 hours, respectively (P less than 0.01). In the twice-weekly series, maximal induction was observed only at the 4th week, the mean values on admission and at 4 weeks being 4.9 and 3.7 hours, respectively (P less than 0.01). Serum activity of gamma glutamyl transferase was not found to be a suitable in vivo marker to monitor induction of the hepatic microsomal enzymes as no significant changes were observed in the activity of this enzyme in any of the 3 series during the 4-week period.