RESUMO
PURPOSE: The combination of a shortage of cornea grafts in France and a national average contamination rate of 9% to 10%, has led us to search for the origins of this contamination. The objective of our study was to reduce the number of unusable grafts resulting from contamination of corneas in organ culture. METHODS: An external audit was carried out by an independent pharmacist on the removal conditions and treatment procedures for corneas. An environmental study was carried out, consisting of microbiological sampling of the corneas of donors who just died (<24 hours) as well as water and air samples in the premises used for removal. The Cornea Bank's procedures were submitted to a microbiological risk analysis using the "failure mode effects and criticity analysis" (FMECA) method. RESULTS: The critical contamination periods were found to be before removal, during mortuary washing and during decontamination of the conjunctival cul-de-sac at the removal stage. The corrective measures taken have reduced contamination rates by half in 1 year. CONCLUSION: Highlighting the sources of contamination has led to the implementation of effective targeted and low-cost measures that have allowed us to reduce significantly the number of cornea graft losses as a result of bacterial and fungal contamination.
Assuntos
Córnea , Transplante de Córnea , Contaminação de Medicamentos/prevenção & controle , Exposição Ambiental/efeitos adversos , Soluções para Preservação de Órgãos/normas , Doadores de Tecidos , Preservação de Tecido/métodos , Humanos , Técnicas de Cultura de Órgãos , Fatores de RiscoRESUMO
French blood banks recently implemented nucleic acid testing (NAT) of all blood donations to reduce the risk of HIV transmission during the pre-seroconversion period. For tissue donation, HIV infection screening relies on HIV p24 antigen and anti-HIV-1 and 2 antibody detection. In this report, two related cases of infectious donations are described from a cornea donor during the preseroconversion window who was infected by an HIV antibody and NAT negative blood donor. After investigation, the blood donor was found to be herself in the preseroconversion window. Two months after donation, she was found to be HIV positive. The residual risk of HIV infectious blood donations since NAT has been introduced is estimated to be lower than one out of 2.5 millions. Individual NAT instead of minipool testing would not increase significantly the blood transfusion safety. In contrast, introduction of NAT should be considered to increase tissue donation safety as soon as such screening will be possible technically.
Assuntos
Doadores de Sangue , Sangue/virologia , Infecções por HIV/diagnóstico , Infecções por HIV/transmissão , HIV-1 , Doadores de Tecidos , Transplantes/virologia , Idoso , Anticorpos Antivirais/sangue , Sequência de Bases , Feminino , Genes Virais , Proteína do Núcleo p24 do HIV/análise , Infecções por HIV/prevenção & controle , Protease de HIV/genética , Transcriptase Reversa do HIV/genética , HIV-1/genética , HIV-1/imunologia , HIV-1/isolamento & purificação , Humanos , Dados de Sequência Molecular , RNA Viral/sangue , Alinhamento de Sequência , Homologia de Sequência do Ácido NucleicoRESUMO
BACKGROUND: Nitric oxide (NO) might be involved in liver response to local ischemia-reperfusion injury. METHODS: A specific NO-sensitive electrode was inserted into liver parenchyma of anesthetized rabbits. After a 45-min period of stable NO signal, the vascular pedicle of the caudal lobe of the liver was clamped for 45 min, then the clamp was removed. Perfusion of the right upper lobe was left unchanged. The same procedure was applied in other animals after administration of a long-acting nonspecific NO synthase inhibitor NAPNA. RESULTS: Occlusion of the caudal pedicle was associated with a mean threefold increase in NO signal measured in the caudal lobe. After unclamping, this signal returned within 8 min to baseline value and remained stable for the next 6 h. In the right upper lobe, NO signal was unaffected by caudal lobe ischemia. By the end of the 6-h reperfusion period, administration of the NO inhibitor l-NAME led to a suppression of the NO signal, thus demonstrating the specificity of the measurement. Plasma nitrate and nitrite concentrations remained almost unchanged during the study period in all groups. In animals whose NO synthases had been previously inhibited by NAPNA, clamping the caudal pedicle for 45 min was still associated with a significant increase in caudal lobe NO signal. CONCLUSION: Nitric oxide is present in liver parenchyma, and its generation is dramatically affected by an ischemia injury. The increased NO generation during local ischemia is, at least in part, independent of NO synthases.
