Medical Radiology and Radiation Safety. 2014. Vol. 59. No. 2. P. 30-38

RADIATION MEDICINE

А.V. Barabanova, А.А. Gordeeva, N.V. Zinovyeva

Early Erythropenia in Acute Radiation Disease after Non-Uniform Exposure: Possible Pathogenetic Mechanisms

Burnasyan Federal Medical Biophysical Center of FMBA, Moscow, Russia. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

ABSTRACT

Purpose: To study the features of acute radiation disease in group of patients exposed to radiation with non-uniform distribution of absorbed dose within the body; the time and grade of possible early erythropenia estimation; clarify its pathogenesis.

Material and methods: Medical histories of 25 patients suffered with acute radiation disease from non-uniform exposure: more than three times gradient of dose by body with maximal local dose higher 10 Gy. Three groups of patients were considered dependently on type of radiation: gamma-radiation 11 patients, gamma-neutron and gamma-beta groups by 7 patients each. Clinical picture in all patients was characterized by compound of bone marrow syndrome (BMS) with local radiation injury (LRI). The time of appearance and the grade of erythropenia were registered and were compared with the main clinical signs of the disease.

Results: Early erythropenia (drop to 3.5×10¹²/l and lower) in period not later than end of the second week was registered in 14 cases with the most severe and spread local radiation injury (LRI). Some slightly expressed decrease of erythrocytes’ number, or the same later its’ appearing, was found in cases with some less expressed, or not so spread LRI. There was no decrease of erythrocytes in three patients with the most limited by surface LRI. There was no correlation between the grade of erythropenia and bone marrow syndrome (BMS) severity. Decrease of erythrocyte was registered at the same time (or slightly later), as an oedema and necrosis in zone of LRI developed, and that corresponded to the period of significant microcirculation’s disorders and following endogenous intoxication developing.

Conclusion: The absence of correlation between the grade and time of erythropenia and BMS severity, as well as coincidence in time of erythropenia appearance with severe edema and necrosis in zone of local injuries lets us to suppose that intravascular hemolysis is the main cause of erythropenia in patients with acute radiation syndrome resulted from non-uniform irradiation.

Key words: acute radiation disease, non-uniform exposure, bone marrow syndrome, local radiation injury, erythropenia