Aim: to show the clinical features of subacute course of subacute course of radiation disease and how they differ from the typical manifestations of acute and chronic radiation syndrome. Material and methods. Materials of the Burnasyan Federal Medical and Biophysical Center Register of acute radiation disease (ARS) in the Former USSR and Russia and Materials of a Burnasyan Federal Medical and Biophysical Center database of workers "Mayak" with chronic radiation syndrome (CRS) were analyzed. There were selected 22 patients with radiation syndrome due to fractionated or prolonged accidental exposure (the main group of patients). There were formed two subgroups for comparison: patients with a typical marrowy syndrome of acute radiation disease and with chronic radiation syndrome. Statistical analysis of results was made by means of statistical software package Statistica v. 6.1 for Windows (StatSoft Inc., USA) and Microsoft Excel 2010. Results. It was found that subacute course of radiation syndrome is possible under radiation exposure with medium dose rate in the range of 0.1-0.3 Gy/day Early symptoms of the disease as a primary reaction symptoms are completely absent. First complaints appeared in the earliest one month after the start of work in adverse conditions, on the average 6 months. In the period of formation there is a pancytopenia in the peripheral blood. Duration of the formation period was also determined. In this case radiation cataracts in patients are not observed. After the termination of radiation exposure hematopoietic recovery is slow, possibly incomplete with a high probability of hemoblastosis development. Conclusions. There has been described the subacute course of radiation disease by analyzing the clinical material of patients with radiation syndrome, there has been analyzed the clinical criteria that distinguish subacute radiation syndrome from acute and chronic.
Krasnyuk V.I., Konchalovsky M.V., Ustyugova A.A. Clinical features of subacute course of radiation disease // Saratov Journal of Medical Scientific Research, Vol. 10, Issue 4, 2014, pp. 858-862

There had been analysed cases of radiation syndrome which clinical picture takes an intermediate place between the acute radiation syndrome (ARS) and the chronic radiation syndrome (CRS), and differs from them because of a subacute. This variant of disease can develop as a result of the fractioned or prolonged radiation lasting from several days to several weeks. Development of primary reaction took place only in the extremely hard cases which ends with an early fatality. After the general radiation the marrow failure was characterized by directly expressed formation and restoration period, specific features of which were defined by the radiation duration, a total dose and dose derivative. The most typical outcomes of a subacute radiation syndrome are death from infectious complications in the period of an eruptive phase or leukosis development in the remote period.
Krasnyuk V.I., Ustyugova А.А. Feasibility of radiation dose range capable to cause subacute course of radiation syndrome // Saratov Journal of Medical Scientific Research, Vol. 9, Issue 4, 2013, pp. 895-896