Comparison of X-ray vs. gamma irradiation of CPDA-1 red cells

Quality control of blood irradiation with a teletherapy unit: damage to stored red blood cells after cobalt-60 gamma irradiation

BACKGROUND

Previous publications have documented the damage caused to red blood cells (RBCs) irradiated with X-rays produced by a linear accelerator and with gamma rays derived from a 137Cs source. The biologic effects on RBCs of gamma rays from a 60Co source, however, have not been characterized.

STUDY DESIGN AND METHODS

This study investigated the effect of 3000 and 4000 cGy on the in vitro properties of RBCs preserved with preservative solution and irradiated with a cobalt teletherapy unit. A thermal device equipped with a data acquisition system was used to maintain and monitor the blood temperature during irradiation. The device was rotated at 2 r.p.m. in the irradiation beam by means of an automated system. The spatial distribution of the absorbed dose over the irradiated volume was obtained with phantom and thermoluminescent dosimeters (TLDs). Levels of Hb, K+, and Cl(-) were assessed by spectrophotometric techniques over a period of 45 days. The change in the topology of the RBC membrane was investigated by flow cytometry.

RESULTS

Irradiation caused significant changes in the extracellular levels of K+ and Hb and in the organizational structure of the phospholipid bilayer of the RBC membrane. Blood temperature ranged from 2 to 4 degrees C during irradiation. Rotation at 2 r.p.m. distributed the dose homogeneously (92%-104%) and did not damage the RBCs.

CONCLUSIONS

The method used to store the blood bags during irradiation guaranteed that all damage caused to the cells was exclusively due to the action of radiation at the doses applied. It was demonstrated that prolonged storage of 60Co-irradiated RBCs results in loss of membrane phospholipids asymmetry, exposing phosphatidylserine (PS) on the cells' surface with a time and dose dependence, which can reduce the in vivo recovery of these cells. A time- and dose-dependence effect on the extracellular K+ and plasma-free Hb levels was also observed. The magnitude of all these effects, however, seems not to be clinically important and can support the storage of irradiated RBC units for at last 28 days.

Effect of gamma irradiation with 30 Gy on the coagulation system in leukoreduced fresh-frozen plasma

BACKGROUND

The aim of this study was to investigate the effect of gamma irradiation with 30 Gy on the coagulation system in leukoreduced fresh-frozen plasma (FFP).

STUDY DESIGN AND METHODS

In 74 FFP units that had been stored for 352 +/- 103 days below -30 degrees C, the following variables were determined in parallel in an irradiated and not irradiated half: prothrombin time (PT); activated partial thromboplastin time (APTT); thrombin time; antithrombin III; protein C; protein S; von Willebrand factor antigen; ristocetin cofactor; plasminogen-alpha(2)-antiplasmin; the coagulation factors fibrinogen, factor (F)II, FV, FVII, VIII, F IX, FX, FXI, FXII, FXIII, and activated factor XII (FXIIa); D-dimer; fibrin monomer; thrombin-antithrombin complex; prothrombin fragment 1 + 2 (F1+2); plasmin-alpha(2)-antiplasmin complexes (PAPs); and platelet factor 4. The FVII activity ratio was assayed to quantify activation of FVII.

RESULTS

Irradiation with 30 Gy resulted in a reduction of APTT (35.0 +/- 4.1 sec vs. 34.4 +/- 4.1 sec; p = 0.00000006) and PT (89.8 +/- 8.2% vs. 90.7 +/- 8.0%; p = 0.002) and a significant increase of the activities of the coagulation factors FII, FV, FVII, F IX, FX, and FXII. FVIII activity decreased from 118 +/- 31 to 116 +/- 32 percent (p = 0.02). Activation of the coagulation system was shown by an increase in the FVII activity ratio (1.19 +/- 0.29 vs. 1.31 +/- 0.34; p = 0.0000001), FXIIa (0.81 +/- 0.50 ng/mL vs. 0.90 +/- 0.51 ng/mL; p = 0.006), and F1+2 (1.19 +/- 0.20 nmol/L vs. 1.24 +/- 0.20 nmol/L; p = 0.000005) after irradiation with 30 Gy, whereas an increase of PAP (16.2 +/- 11.5 ng/mL vs. 20.2 +/- 12.0 ng/mL; p = 0.0004) demonstrated activation of the fibrinolytic system. No negative influence of irradiation with 30 Gy on inhibitors of coagulation was observed.

CONCLUSION

Gamma irradiation of leukoreduced FFPs with 30 Gy results in a significant but very weak activation of the coagulation and fibrinolytic system in FFPs.

Transfusion-associated graft-versus-host disease in immunocompetent patients: case series and review of the literature

BACKGROUND

Transfusion-associated graft-versus-host disease (TA-GVHD) is a fatal complication of transfusion of blood products that usually affects immunocompromised patients. Articles reporting this condition in immunocompetent recipients are usually from countries that still have problems in irradiation of blood products.

CASE REPORTS

This report presents fatal TA-GVHD in four immunocompetent patients referred from rural areas where blood irradiation is still not the routine procedure to our tertiary-care center between July 2004 and July 2005. A similar history and chronological order of events were observed: fresh whole-blood transfusion from relatives, fever, rash, liver dysfunction, diarrhea, and pancytopenia. Skin biopsies demonstrated Grade II to III GVHD involvement. Marrow biopsies showed hypoplasia. In two cases, HLA typing studies were performed. Donors were homozygous for a shared HLA haplotype in the patients. All cases were admitted to the intensive care unit within 3 weeks after transfusions with the diagnosis of sepsis, which rapidly progressed to septic shock and multiorgan failure. Another common observation was Candida albicans growth in blood cultures. Unfortunately, all died despite prompt and appropriate sepsis treatment, along with immunomodulatory therapy.

CONCLUSION

TA-GVHD is probably more prevalent than reported in the literature. It must be considered in the differential diagnosis, if the patient with a recent transfusion history admits with fever, skin rash, abnormal liver function tests, and pancytopenia associated with hypoplastic marrow. In rural areas where gamma irradiation is not possible, the overall policy of transfusion (e.g., restriction of transfusion indications and alternative methods for pathogen inactivation) should be reassessed.