Objective: To investigate the change of immunosuppressive acidic protein (IAP) in sera of patients with pulmonary tuberculosis (TB) and its clinical value.
Method: IAP in sera of 336 patients suffering from pulmonary TB and controls was detected by agar diffusion assay.
Results: In pulmonary TB, healthy controls and non-TB respiratory diseases, the level of IAP was (797 +/- 168) mg/L, (367 +/- 71) mg/L and (404 +/- 75) mg/L, respectively. If > 500 mg/L was regarded as positive threshold, the positive rates in the above groups were 96.7%, 9.2% and 9.6%, respectively. IAP positive rates in cases of primary, disseminated, infiltrative, chronic fibro-cavernous pulmonary TB and tuberculous pleuritis were 100, 0%, 100.0%, 96.0%, 98.6% and 96.9%, respectively. IAP was significantly higher in progressive pulmonary TB than in stable pulmonary TB, and was decreased when patients' condition improved after treatment.
Conclusion: Detection of IAP in sera of patients with pulmonary TB can reflect patients' immunosuppression status and the severity of the disease, and may be useful in assessing treatment effect and evaluating prognosis.