Alpha-methyldopa has been demonstrated to be safe for use during pregnancy and is now used to treat gestational hypertension. In pregnancy, alpha-methyldopa-induced autoimmune hemolytic anemia does not have typical features and the severity of symptoms ranges from mild fatigue to dyspnea, respiratory failure, and death if left untreated. A case of alpha-methyldopa-induced autoimmune hemolytic anemia in a 36-year-old gravida 2, para 1 woman at 37+6 weeks of gestation is reported herein along with the differential diagnostic procedure and the potential risks to the mother and the fetus.
Drug-induced autoimmune hemolytic anemia (DIAIHA) can be underrecognized in pregnancy due to the physiological dilutional anemia observed. Autoimmune hemolytic anemia (AIHA) accounts for 0.8–3 per 100 000 cases of anemia [
A case of alpha-methyldopa-induced autoimmune hemolytic anemia of pregnancy is reported herein along with the major problems in differential diagnosis and the risks posed to both the mother and the fetus.
A 36-year-old gravida 2, para 1 woman at 37+6 weeks of gestation presented to the obstetric unit for elective cesarean delivery due to a previous cesarean section for breech presentation. Medical history included
A healthy male infant with Apgar scores of 9 and 10 at the first and the fifth minutes, respectively, was born by cesarean section under combined spinal-epidural anesthesia. Physical examination of the newborn was unremarkable with no signs of hemolysis throughout its stay in the fetal medicine unit. In the same evening, maternal hemoglobin levels decreased to 7 g/dL with no signs of hemorrhage from the surgical field and reached 6.1 g/dL over the next three days. Direct antiglobulin (DAT) test was strongly positive (3+) for IgGs. The baby’s blood group type was O Rh(−), and the mother’s blood group type was AB Rh(+). Serum liver, renal functions, coagulation studies, and urine analysis were normal. Alpha-methyldopa was discontinued immediately upon positive DAT and was replaced by intravenous hydralazine. Hemoglobin levels returned to the pregestational levels (10 g/dL) one month after alpha-methyldopa discontinuation, still with a positive DAT.
Alpha-methyldopa-induced AIHA is rare in pregnancy with only few cases published. Hemolysis due to alpha-methyldopa occurs via autoantibodies targeted against red blood cells [
Alpha-methyldopa-induced AIHA does not have typical features, and the severity of symptoms ranges from mild fatigue [
Alpha-methyldopa-induced AIHA is uncommon and in the laboratory setting yields similar findings with WAIHA: positive DAT, positive indirect antiglobulin test, and positive elution; however, the mechanism of hemolysis is more complex and heterogeneous with immune dysregulation, autoantibodies via molecular mimicry, and drug adsorption causing altered red blood cell membrane antigens [
Distinguishing DIAIHA from WAIHA can be difficult. The clinician should have in mind that WAIHAs may be associated with platelet function disorders and pancytopenias. In the perioperative setting, it appears that regional anesthetic techniques can be applied only upon exclusion of platelet function disorders. In the present case, the medical history raised suspicion of alpha-methyldopa-induced AIHA, and coagulation parameters let us opt for combined spinal epidural anesthesia that would be also beneficial for hypertension.
Definitely distingushing WAIHAs from DIAHAs requires complex and time-consuming testing, performed by hematology referral centers. In the obstetric setting, this is not always possible, given the urgency of the procedure in some cases. Drug history remains crucial for the investigation, and drug cessation followed by hemolytic anemia resolution remains the only reliable final confirmation of DIAIHA.
Drug-induced autoimmune hemolytic anemia
Autoimmune hemolytic anemia
Warm autoimmune hemolytic anemia.
Written informed consent for publication in Case Reports in Obstetrics and Gynecology was obtained from the patient.
The authors report no conflict of interests.