Introduction. Rheumatoid arthritis (RA) is the most common inflammatory disease of the joints, the prevalence of which is increasing in the population, leading to the emergence of new cases of the disease in young and middle-aged people, which has enormous medical and social significance. The study objective was to optimize the diagnosis and prediction of seronegative early rheumatoid arthritis outcomes by identifying the most significant clinical, laboratory and instrumental predictors of joint destruction. Material and methods. The study includes 82 patients (22 men and 60 women), aged 17 to 70 years (average of 45.02±12.4 years), with the presence of articular syndrome (arthritis). All subjects were classified in the following groups: group I – 41 patients - 11 men and 30 women, whose average age was 44.46±13.36 years (average duration of the disease 6.0±2.9 months) with early seronegative rheumatoid arthritis (eRA), and group II consisted of 41 patients aged 45.55±11.12 years - 11 men and 30 women, with a diagnosis of seropositive rheumatoid arthritis (RA) (average duration of the disease of 6.8±3.7 months). Results. In the seronegative eRA group, the average Value of “prognostic index” (PrI) calculated from the data at the time of the initial survey was 5.67±1.72 points. PrI values in patients with transformation in RA within 1 year were significantly higher – 6.68±1.61, than without transformation in RA 4.52±0.96 points, p < 0.0001. At the same time, the values of PrI < 6 points were observed in 17 (20.7%) patients, PrI > 8 – in 25 (30.48%) patients, intermediate values (between 6 and 8 points) – in 40 (48.78%) patients, p < 0.001. Thus, in most patients with transformation in RA, the PrI values were more than 6 points. Conclusions. In 53% of patients with seronegative RA, there is a transformation into seropositive rheumatoid arthritis during the first 18 months of the development of the disease. Features of early rheumatoid arthritis, in comparison with stabile RA are a polyarthritis presentation of the onset with damage to the joints of the hands, prolonged morning stiffness (more than 1 hour), moderate or high level of activity, the presence of productive synovitis and erosion during ultrasonography.