Acute radiation syndrome

1. ACUTE RADIATION
SYNDROME
By:A.Haghbin

2. Lecture organization
Introduction
ARS manifestations
Haematological syndrome
Cutaneous Radiation Syndrome
Gastrointestinal syndrome
Neurovascular syndrome
Triage of injured persons
2- 45

3. Introduction
Acute radiation syndrome (ARS)
epidemiologic studies of human populations exposed
ARS threat
3- 45

4. dose-response relationship
LD 50/60
LD 50/60
4- 45

5. 5- 45

6. Factors decreasing LD50/60
• Contribution of high LET radiation
• dose rate
• uniformity of exposure
• portion of the body exposed
• radiosensitivity
• Coexisting trauma combined injury
• Coexisting infection
• age and health of the victim
6- 45

7. Phases of ARS
Medical Treatment Protocols for Radiation
Accident(METREPOL):
Hematological
Cutaneous
Gastrointestinal
Neurovascular
7- 45

8. Haematopoietic syndrome (HPS)
Bone marrow damaged by radiation injuryNormal bone marrow cells
Exposure to a dose range of 3-8 Gy :Death at 3 weeks
8- 45

9. 9- 45

10. 10- 45

11. Haematological response to 1 Gy, whole body
exposure to ionizing radiation
11- 45

12. Prognosis According to the Lymphocyte Count within the First 48
Hours after Acute Exposure to Penetrating Whole-Body Radiation
12- 45

13. Haematological response to 3 Gy, whole body
exposure
13- 45

14. Granulocyte counts and dose relationship after
irradiation
14- 45

15. Phases of haematopoietic syndrome (HPS)
Prodromal phase symptoms
Latent phase
Manifest illness phase
15- 45

16. Medical management
Cytokines
• Granulocyte-macrophage stimulating factor (GM-CSF) -
Sargramostim(Leukine)
• Granulocyte colony stimulating factor(G-CSF) - Filgastrim
(Neupogen)
• Interleukin series (IL 1-16)
16- 45

17. Medical management
Platelet support
Thrombopoietin
Erythropoietin
Antibiotics
Bone Marrow Transplant
17- 45

18. Cutaneous Radiation Syndrome (CRS)
18- 45

19. 19- 45

20. Medical management
Anti-Inflammatory
Glucocorticoids
Antihistamine
20- 45

21. Gastrointestinal syndrome(GI)
21- 45

22. Pathophysiology of the GI Syndrome
Exposure to a dose range of 8-30 Gy :Death at 9 days
Depletion of the epithelial cells lining lumen of gastrointestinal tract
Intestinal bacteria gain free access to body
Haemorrhage through denuded areas
Loss of absorptive capacity
22-45

23. Phases of Gl syndrome
Prodromal period
Latent (subacute) phase
Manifest illness
23- 45

24. Systemic effects of GI syndrome
Malabsorption
Fluid and electrolyte shifts
GI bleeding
Sepsis
Paralytic ileus
24-45

25. Medical Management
Antibiotics
Sucralfate & prostaglandin
Cytokine G-CSF
Immunoglobulins (IgG)
25- 45

26. Pulmonary effects
Irradiated lung tissue Pulmonary fibrosis
26--45

27. Neurovascular syndrome
(NVS)
27- 45

28. 28- 45

29. 29- 45

30. Neurovascular syndrome
(NVS)
At 30 Gy and above
Endothelial cell damage
30- 45

31. Phases of NV syndrome
Prodromal period
Latent (subacute) phase
Manifest illness
31- 45

32. Medical Management
Glucocorticoids
Electrolyte compensation
Mannitol
32- 45

33. Summary
33-45

34. Trıage of ınjured persons
Measurement of severity
• Prodromal effects
• Biodosimetry
• Physical dosimetry
34- 45

35. Assessment of Biodosimetry Methods for
Radiological Incident
Hematological biodosimetry
Cytogenetic biodosimetry
DNA damage assays
Emerging methods -“omic” assays
Bio-physically based dosimetry
35- 45

36. Hematological biodosimetry
Lymphocyte depletion kinetic assay
Ratio of neutrophils to lymphocytes
36- 45

37. Change of lymphocyte counts in initial days of ARS
depending on dose of acute WB exposure
Lymphocyte counts
(cells/L)
6 days after first
exposure
Dose (Gy)Degree of ARS
1500-25000.1-1.0Preclinical phase
700-15001.0-2.0Mild
500-8002.0-4.0Moderate
300-5004.0-6.0Severe
100-3006.0-8.0Very severe
0-50>8.0Lethal
37- 45

38. Cytogenetic biodosimetry
Dicentric chromosome assay
Premature chromosome condensation assay
38- 45

39. DNA damage assays
Gamma-H2AX foci assay
Cytokinesis block micronucleus assay (CBMN)
39- 45

40. Emerging methods -“omic” assays
Gene expression biomarkers
MicroRNA expression
Protein biomarkers
Metabolic biomarkers
40- 45

41. Bio-physically based dosimetry
Electron paramagnetic resonance
Optically stimulated luminescence (OSL)
41- 45

42. Biologics as countermeasures for acute
radiation syndrome
42-45

43. 43-45

44. 44- 45

45. Reference
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