Salivary lysozyme and related parameters of a predominantly Chinese, HIV-infected cohort in Hong Kong.

OBJECTIVES

To evaluate the salivary lysozyme concentration, flow rate and pH of a predominantly Chinese, HIV-infected group in Hong Kong, and to compare with an equal number of age and gender-matched HIV-free individuals.

STUDY DESIGN

A prospective longitudinal study over a 12-month period of 32 predominantly Chinese, male, HIV-infected group in a hospital setting in Hong Kong. Whole saliva collection by expectoration, lysozyme evaluation by 'lysoplate method'; pH and flow rate evaluation using standard methods and correlation with other clinical parameters using regression analysis.

RESULTS

The flow rate and the pH of saliva were lower compared with HIV-free, healthy individuals (both P < 0.0001) and salivary lysozyme concentration of the HIV-infected group was 23% higher compared with the HIV-free group (P < 0.001), though there was no significant difference between the lysozyme output (P > 0.05) expressed as microg min-1. On multiple regression analysis, intravenous drug users had a higher salivary lysozyme concentration compared with the homosexual group (P = 0.0015) though other variables investigated were not significantly related to the salivary lysozyme concentrations.

CONCLUSIONS

The significant changes in the flow rate, pH value and lysozyme concentration of whole saliva of the HIV-infected individuals as compared with the HIV-free, healthy individuals, may be due to the disease itself or a combination of factors including the medications used in the disease management.