Marjorie Hunt

Anti-f sensitization detected by an acidified indirect Coombs test.

1 A case of blood group incompatibility is presented with evidence indicating that anti‐f was the antibody involved. 2 The anti‐f antibody was detected by means of the indirect Coombs Test modified by acidifying the patients serum. 3 The antibody gave a stronger reaction with “ff” than with “Ff” blood cells and reacted with blood specimens of various Rh‐Hr genotypes in a manner which would be expected for the anti‐f antibody. 4 There is some evidence that the anti‐f antibody in this case was an auto‐antibody, capable of attacking the patients own blood cells.

The Leukemias in Relation to Age, Sex, and Blood Group

1 An analysis was made of 352 cases of leukemia with regard to age, race, sex, and blood group. 2 In this sample, which included 92 pediatric cases, the predominant type of leukemia was acute lymphocytic. 3 The distributions of ABO and Rh blood groups were as expected except for an increase of group O subjects in monocytic leukemia. 4 For each type of leukemia, the sex ratios were calculated with regard to the age groups primarily affected: a) In acute lymphocytic (103 cases) males predominated in the 5–14 age group; b) In chronic lymphocytic (91 cases), there was a statistically significant increase in males; c) In acute myelocytic (25 cases), males also appeared to predominate, especially in the over‐50 age group; and d) In chronic myelocytic (80 cases), females predominated in the under‐60 age groups, while in the over‐60 age groups, males were more numerous. In monocytic (44 cases) and in stem cell (9 cases) leukemias, no definite pattern of age or sex distribution could be established. 5 While the above results may serve to indicate certain trends, the findings should not be considered conclusive because of the smallness of the sample.

Further observations on the antepartum prediction of hemolytic disease of the newborn

Summary The routine testing for Rh sensitization, throughout every Rh-incompatible pregnancy, is of definite value in the antenatal prediction of hemolytic disease of the newborn. This is especially true when five factors are taken into consideration: (1) the presence of “blocking” antibodies, (2) a significant quantity of antibodies, (3) their existence for more than ten weeks before delivery, (4) their presence on every successive test, and (5) the presence of ABO compatibility between mother and baby. When all five factors were “positive”, only two out of twenty-eight Rh-positive babies escaped hemolytic disease. If but one factor was “negative”, twenty-eight out of thirty babies escaped the disease, and if two factors were missing, all babies were healthy. Such predictions have been of value in planning neonatal therapy, and should be of great assistance in evaluating the effects of early induction of labor or the benefits resulting from any type of antenatal therapy.

The clinical significance of Rh antibodies (Rh agglutinins and blocking antibodies) in the sera of Rh-negative mothers; A study of 179 cases

Abstract A detailed analysis is presented of both the individual and collective laboratory findings in 179 pregnant Rh-negative women. The study was under-taken in order to determine the relationships which might exist between the serologic data observed in the mothers and the clinical conditions found in the infants born to them, with the ultimate purpose of presenting the obstetrician with an antepartum interpretation of the significance of the laboratory findings in Rh-negative patients. 1. 1. In order to facilitate the expression of the end results and significance of iso-immunization in pregnancy, the collective data were classified and studied according to the Rh characteristic and clinical outcome of the infant: Group I—normal Rh-negative infants; Group II—normal Rh-positive infants; Group III—Rh-positive infants with subclinical hemolytic disease of the newborn; and Group IV—Rh-positive infants with frank hemolytic disease of the newborn. 2. 2. Of 61 Rh-negative women delivered of normal Rh-negative children, 9 showed isolated low titers of Rh agglutinins ante partum. 3. 3. The isolated occurrence of Rh antibodies of low titer in Rh-negative women having Rh-positive husbands may be significant under circumstances where evidence of immunization occurs early in pregnancy or where blocking antibodies mask the Rh agglutinins. Apparently spurious positive tests for Rh antibodies may be due to the “carry-over” phenomenon or to pregnancy itself. 4. 4. Antibody formation occurred more often among multiparous than among primiparous women. Nevertheless, it is important to test Rh-negative women repeatedly for Rh antibodies, regardless of parity. The ease with which some individuals may become immunized and the fact that an opportunity for previous immunization may have been forgotten influences the results of the tests in primiparous women. 5. 5. Rh-antibody trends were determined for all women showing development of sensitization and their possible significance is shown in relation to the outcome of the child. In general, no patient demonstrating a high antepartum titer of either antibody, especially if their presence were detected early in pregnancy, was delivered of a clinically normal Rh-positive infant. 6. 6. A comparison of the occurrence of Rh agglutinin and blocking antibodies indicates that no definite cause and effect relationship between them can be inferred from our data. There appears to be an apparent reciprocity between the titer trends of these two antibodies, the significance of which is not entirely clear. The Rh agglutinin appears to be demonstrable in the maternal serum by the twentieth week ante partum. The blocking antibody follows the appearance of the Rh agglutinin and may not be present in demonstrable amounts earlier than about the tenth week ante partum. 7. 7. The hypothesis is suggested that blocking antibody may be produced, not as a defense for the mother as is Rh agglutinin, but as a protection for the erythrocytes of the fetus.

A study of the occurrence of normal Rh-negative infants born to sensitized Rh-negative women.

Summary 1. Thirty instances of normal Rh negative infants born to sensitized Rh-negative mothers were studied. 2. Small amounts of Rh antibodies (2+ or less) occurring inconsistently in ante-partum tests were regarded as nonspecific and of no significance. 3. The tests for Rh sensitization showed appreciable amounts of Rh antibodies to be consistently present in the sera of 17 Rh-negative women who subsequently bore Rh-negative infants. In seven instances the ante-partum antibody titer increased in intensity and in ten instances the antibody titer remained constant. 4. All women in whom the antibody titers were consistently present (Group I) showed evidences of a high degree of Rh immunization in terms of the amount and type of antibody present, and in some instances by having previously borne an erythroblastotic infant. 5. The only basis for the prediction of an Rh-negative infant to be borne of a sensitized Rh-negative woman is first, the determination of the Hr status of the husband, and second, the trend of the maternal ante partum Rh antibody titer. If the husband is heterozygous (Rhrh) and the titer remains constant, the baby will likely be Rh negative; however, some highly immunized Rh negative women may actually demonstrate a rising Rh antibody titer and still bear an Rh-negative infant.