The impact of immune disturbances on the failure of antituberculosis treatment

Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis complex, with an evolution and treatment outcome determined by the interaction between the mycobacterial and human genotypes. Various deficiencies of innate immune response starting from the first encounter of M. tuberculosis with lung cells endanger host infection control due to decreased triggering of cellular immune resistance and disturbed humoral immunity. Disturbed cell mediated immunity, known as the basic immune response in tuberculous infection, contributes to the deficient generation of central necrosis granuloma, consequently being responsible for severe clinical aspects and low final outcome. The tuberculosis patient's immune assessment is important before treatment initiation, for establishing the risk reduction measures and increasing success rate.

The immune study was conducted on 54 new pulmonary tuberculosis cases with treatment failure, 34 new pulmonary tuberculosis cases that successfully ended the treatment and 50 healthy group individuals. Immune assays performed were: blastic transformation of lymphocytes induced by different antigens, quantitatitve assessment of cellular immunity through CD4+ T cell and CD8+ T cell phenotyping, humoral immunity - through immunoglobulin isotyping, innate resistance - through phagocyte activity of neutrophils, the titter of anti-tuberculosis antibodies and the serum level of circulating immune complexes. Investigations were performed at the onset the treatment and at the end of intensive phase of the standard anti-tuberculosis treatment.

Immune disturbances evidenced in patients with treatment failure were: important deficiencies of cellular immunity, hyperactivity of humoral immunity and deficiencies of innate immunity. High predictive value for treatment failure showed the indices: deficiency of T lymphocytes count (OR=62.5) and T helper count (OR=12.5), high level of circulating immune complexes (OR=9.801), deficiency of innate resistance (decreased phagocytating index OR=2.875).

For increasing the treatment success rate, the study of immune disturbances must be performed before of antituberculosis treatment initiation, especially of cellular immunity for the early start of immune adaptive treatment.