Medical Devices; Hematology and Pathology Devices; Classification of Blood Establishment Computer Software and Accessories. Final rule.

The Food and Drug Administration (FDA, Agency, or we) is issuing a final rule to classify blood establishment computer software (BECS) and BECS accessories (regulated under product code MMH) into class II (special controls). FDA has identified special controls for BECS and BECS accessories that are necessary to provide a reasonable assurance of safety and effectiveness. FDA is also giving notice that the Agency does not intend to exempt BECS and BECS accessories from premarket notification requirements of the Federal Food, Drug, and Cosmetic Act (FD&C Act).

Frequency of DEA 1 antigen in 1037 mongrel and PUREBREED dogs in ITALY.

BACKGROUND: The prevalence of dog erythrocyte antigen (DEA 1) in canine population is approximately 40-60%. Often data are limited to a small number of breeds and/or dogs. The aims of this study were to evaluate frequency of DEA 1 in a large population of purebred and mongrel dogs including Italian native breeds and to recognize a possible association between DEA 1 and breed, sex, and genetic and phenotypical/functional classifications of breeds. Frequencies of DEA 1 blood group collected from screened/enrolled blood donors and from healthy and sick dogs were retrospectively evaluated. The breed and the sex were recorded when available. DEA 1 blood typing was assessed by immunocromatographic test on K3EDTA blood samples. The prevalence of DEA 1 antigen was statistically related to breed, gender, Fédération Cynologique Internationale (FCI) and genotypic grouping. RESULTS: Sixty-two per cent dogs resulted DEA 1+ and 38% DEA 1-. DEA 1- was statistically associated with Dogo Argentino, Dobermann, German Shepherd, Boxer, Corso dogs, the molossian dogs, the FCI group 1, 2 and 3 and the genetic groups "working dogs" and "mastiff". DEA 1+ was statistically associated with Rottweiler, Briquet Griffon Vendéen, Bernese mountain dog, Golden Retriever, the hunting breeds, the FCI group 4, 6, 7 and 8 and the genetic groups "scent hounds" and "retrievers". No gender association was observed. CONCLUSIONS: Data obtained by this work may be clinically useful to drive blood donor enrollment and selection among different breeds.

Resolving variable maternal D typing using serology and genotyping in selected prenatal patients.

BACKGROUND: RhIG prophylaxis for D- pregnant women prevents hemolytic disease of the newborn and typically depends on results of serologic D typing. Interpretation and follow-up of weak D serology is variable. Recent recommendations promote genotyping for RHD status determination in those with weak D serology. Canadian Blood Services performs comprehensive serologic prenatal testing in four provinces. Genotyping is used to determine D typing in patients with weak D. STUDY DESIGN AND METHODS: A serologic algorithm identified which patients require genotyping for RHD determination. Genotyping was performed on one of two commercially available platforms. RESULTS: Only 0.4% of D- patients met criteria for genotyping. Sixty-one percent were weak D Type 1, 2, or 3. Thirty percent had a partial or weak D other than Type 1, 2, or 3. Eleven had variants which remained unresolved. Seventeen were D+ and four were D-. CONCLUSIONS: Genotyping of patients with weak D serology led to an identified genotype in most patients. RhIG administration was avoided in 66% who were weak D Type 1, 2, or 3 or were D+. The use of a serologic algorithm to select patients for RHD genotyping identifies a majority of patients with weak D types not at risk for alloimmunization. This approach limits the number of genotyping investigations and the cost of providing classification for weak D types.

Recovery from Extreme Hemodilution (Hemoglobin Level of 0.6 g/dL) in Cadaveric Liver Transplantation.

Decompensated hepatic failure occurred in a patient with a rare blood type. The patient had extreme hemodilution due to massive bleeding during liver transplantation. A shortage of matched and universal donor blood prompted us to transfuse albumin and fresh frozen plasma for intravascular volume resuscitation. The lowest hemoglobin was 0.6 g/dL, accompanied by ST depression and a serum lactate of 100 mg/dL. The accuracy of the measured value of 0.6 g/dL was confirmed. However, the patient recovered from this critical situation after transfusion, and he was eventually discharged from the hospital without significant sequelae. Maintaining normovolemia, administering pure oxygen, ensuring appropriate anesthetic depth, and maintaining minimal inotropic support were essential for this patient's survival during massive bleeding.

Determination of twin zygosity: a comparison of DNA with various questionnaire indices.

This study examined cross-validation and test-retest reliability of questions and questionnaire indices commonly used for twin zygosity classification. Mothers of 58 monozygotic (MZ) and 52 dizygotic (DZ) same sex twin pairs were interviewed by telephone to answer questions regarding the similarity of their twins (mean age = 14.6 +/- 2.8 years). A logistic regression equation correctly classified 91% of both MZ and DZ twin pairs in our sample using 7 of the 12 zygosity questions. The internal consistency for the total questionnaire (Cronbach's alpha) was 0.88. The median two month temporal stability estimate for the individual questions was r = .56 and r = .79 for the test total. For the cross-validation, zygosity classification indices taken from 9 previous studies were applied to our sample and compared to classification according to DNA microsatellite analyses (agreement range = 44 to 100%). The accuracy of the classification indices was significantly lower than the original studies for 62% of the comparisons. If zygosity determination with DNA markers or blood group typing for all subjects is not feasible, rather than using classification indices based on other studies, an optimal classification scheme can be achieved by using a zygosity questionnaire of which the reliability and validity of the questions is established in a random subsample of the same twin cohort.

Biological products; blood specificity designators; technical amendments--FDA. Final rule; technical amendments.

The Food and Drug Administration (FDA) is amending the biologics regulations to correct certain omissions from the designators for blood specificities and make other minor, technical amendments. This action is being taken to clarify and improve the accuracy of the regulations.