Severe hemolytic disease of the newborn caused by JKb antibody: Two case reports and literature review.

BACKGROUND: JKb antibody rarely causes severe hemolytic disease in the newborn except in 1 case, required blood exchange transfusion but later died of intractable seizure and renal failure. Here we describe 2 cases of JKb-induced severe neonatal jaundice requiring blood exchange transfusion with good neurological outcome. CASE PRESENTATION: Two female Chinese, ethnic Han, term infants with severe jaundice were transferred to us at the age of 5- and 4-day with a total bilirubin of 30.9 and 25.9 mg/dL while reticulocyte counts were 3.2% and 2.2%, respectively. Both infants were not the firstborn to their corresponding mothers. Direct and indirect Coombs' tests were positive, and JKb antibody titers were 1:64 (+) for both mothers. Phototherapy was immediately administered, and a blood exchange transfusion was performed within 5 hours of admission. Magnet resonance image showed no evidence of bilirubin-induced brain damage, and no abnormal neurological finding was detected at 6 months of life. CONCLUSION: JKb antibody-induced hemolytic disease of the newborn usually leads to a benign course, but severe jaundice requiring blood exchange transfusion may occur. Our cases suggest good outcomes can be achieved in this minor blood group-induced hemolytic disease of the newborn if identified and managed early enough.

Familial hemophagocytic lymphohistiocytosis type 2 in a female Chinese neonate: A case report and review of the literature.

BACKGROUND: Familial hemophagocytic lymphohistiocytosis type 2 (FHL2) is a rare genetic disorder presenting with fever, hepatosplenomegaly, and pancytopenia secondary to perforin-1 (PRF1) mutation. FLH2 has been described in Chinese but usually presents after 1 year old. We describe a female Chinese neonate with FHL2 secondary to compound heterozygous PRF1 mutation with symptom onset before 1 mo old. We review Chinese FHL2 patients in the literature for comparison. CASE SUMMARY: A 15-d-old female neonate was referred to our hospital for persistent fever and thrombocytopenia with diffuse petechiae. She was born to a G5P3 mother at 39 wk and 4 d via cesarean section secondary to breech presentation. No resuscitation was required at birth. She was described to be very sleepy with poor appetite since birth. She developed a fever up to 39.5°C at 7 d of life. Leukocytosis, anemia, and thrombocytopenia were detected at a local medical facility. CONCLUSION: A literature review identified 75 Chinese FHL2 patients, with only five presenting in the first year of life. Missense and frameshift mutations are the most common PRF1 mutations in Chinese, with 24.8% having c.1349C>T followed by 11.6% having c.65delC. The c.658G>C mutation has only been reported once in the literature and our case suggests it can be pathogenic, at least in the presence of another pathogenic mutation such as c.1066C>T.

Rh-incompatible hemolytic disease of the newborn in Hefei.

BACKGROUND: Anti-D antibody is not the common cause of Rh-isoimmunization in Chinese neonatal jaundice. Recent change in national population policy has followed by an increase in Rh-isoimmunization related hemolytic disease of the newborn (HDN). Unfortunately, regional status of Rh-HDN is unavailable. We hypothesize that Rh-HDN in our region is most commonly due to anti-E antibody. AIM: To investigate the prevalence of hemolytic disease of the newborn due to Rh-isoimmunization in Hefei City. METHODS: Retrospective review of data obtained from Children's Hospital of Anhui and Hefei Blood Center between January 2017 and June 2019. Status of minor blood group antibody was studied in the corresponding mothers. RESULTS: Totally 4138 newborns with HDN admitted during the study period and 116 (2.8%) received blood exchange transfusion (BET). Eighteen newborns (0.43%) with proven Rh-incompatible HDN were identified. All were not the first-born baby. Thirteen mothers were RhD (+) (72%) and five were RhD (-). The distribution of Rh-related antibodies in mothers was ten anti-E (55%), five anti-D (27%), and for one anti-C, anti-c, and anti-E/c (6%) each. Thirteen (72.2%) were qualified for BET, relative risk for BET was 28.9 as compared to other types of HDN, but only 10 received due to parenteral refusal. All (100%) RhD related HDN received BET which is not significantly different from RhE related HDN (81.8%). CONCLUSION: As expected, all Rh-incompatible HDN newborns were not the first-born. Contrary to the Caucasian population, anti-D induced HDN is not the most common etiology. In our region, anti-E (11/18, 61%) is the most common cause of Rh-HDN.