The immune state of patient is the first question in medicine. The fluorescent probe offer for clinicians quick, reliable, reproducible method. The material was built upon findings investigated the possibility of using the original fluorescent probe ABM (an amino derivative of benzanthrone) for the detection of structural/functional alteration in blood plasma albumin and among immunocompetent cells in patients with different pathologies. The spectral characteristics of ABM showed specific differences in each of the differing patients groups; correlate with select immunological parameters (CD4+/CD8+; CD38+, lymphocytes count etc.) and serve as a very important prognostic indicator of long-time survival among patients. There was strong agreement between changes in ABM spectral characteristics and both clinical and pathological estimates of disease severity. Measures of ABM spectral characteristics are useful tool to estimate the immune status of patients. Compared to many commonly used clinical protocols, the fluorescence based method is less expensive and not very time consuming, technically simple and 100X times more sensitive than standard absorbance based methods.