Severe Anaphylaxis in Pregnancy: A Systematic Review of Clinical Presentation to Determine Outcomes

Fetal bradycardia and acidosis during maternal parenteral iron: Case reports and literature review

Iron deficiency anemia is an important problem among pregnant women, and intravenous (IV) iron infusions have been increasingly used. Whether fetal monitoring is required during infusion has been debated, with a recent guideline by Hematologists recommending against such. We report two cases of fetal bradycardia after iron isomaltoside (IIM), in women with otherwise good maternal and fetal health. Both developed dyspnea with desaturation minutes from infusion, followed by persistent fetal bradycardia. Both underwent category 1 CS, with cord arterial pH of 7.08 and 6.94 respectively. Upon literature review, only three case reports on fetal bradycardia in IV iron were identified. For older IV iron formulations, a case was reported after IV dextran test dose, while two cases after ferric gluconate were reported. For the new formulation IIM, only one case was reported so far, but in a woman with Crohn's disease and intrauterine growth restriction. IV iron in pregnancy carries risk of anaphylactic or hypersensitivity reactions, even with the newest formulations and in women with good maternal and fetal health. While rarely reported so far, fetal bradycardia is a possible consequence, commonly preceded by respiratory symptoms. Fetal monitoring should therefore be considered during infusion.

Anaphylaxis-induced premature uterine contractions: a case report and literature review

BACKGROUND

Preterm labor is caused by multiple etiologies, including intra-amniotic infection and/or intra-amniotic inflammation, vascular disorders, cervical disease, decidual senescence, and breakdown of maternal-fetal tolerance. Accumulating evidence in vivo and in vitro has shown that an allergic reaction, including anaphylaxis, can induce preterm uterine contractions. This report describes a case of a pregnant woman who developed anaphylaxis and regular uterine contractions after the ingestion of a strawberry-coated biscuit. We also review the mechanism of allergic reaction (hypersensitivity)-induced preterm labor. Case presentation A 31-year-old woman (gravida 1, para 0) at 30+2 weeks of gestation was admitted to the labor and delivery unit with regular uterine contractions and anaphylactic symptoms after she ingested a strawberry-coated biscuit as a snack. The uterine contractions resolved after the treatment of anaphylaxis by administering antihistamines and epinephrine. The patient subsequently delivered at 39+3 weeks of gestation. The amniotic fluid profile showed no infection or inflammation. A postpartum skin-prick test confirmed a positive type 1 hypersensitivity reaction to the strawberry-coated biscuit.

CONCLUSIONS

We report a case of anaphylaxis-induced uterine contractility in which uterine contractions subsided after the treatment of anaphylaxis. The absence of intra-amniotic infection and/or intra-amniotic inflammation and the cause of the anaphylaxis were confirmed. Our findings indicate that maternal allergic reactions may be one of the mechanisms of preterm labor.

Drug-Induced Anaphylaxis: National Database Analysis

(1) Background: National health system databases represent an important source of information about the epidemiology of adverse drug reactions including drug-induced allergy and anaphylaxis. Analysis of such databases may enhance the knowledge of healthcare professionals regarding the problem of drug-induced anaphylaxis. (2) Methods: A retrospective descriptive analysis was carried out of spontaneous reports (SRs) with data on drug-induced anaphylaxis (SRsAs) extracted from the Russian National Pharmacovigilance database (analyzed period 2 April 2019-21 June 2023). The percentage of SRsAs among SRs of drug-induced allergy (SRsDIAs) was calculated, as well as of pediatric, elderly, and fatal SrsAs. Drugs involved in anaphylaxis were assessed among total SRsAs, pediatric, and elderly SRsAs, and among fatal SRsAs. Demographic parameters of patients were assessed. (3) Results: SRsAs were reported in 8.3% of SRsDIAs (2304/27,727), the mean age of patients was 48.2 ± 15.8 years, and females accounted for 53.2% of cases. The main causative groups of drugs were antibacterials (ABs) for systemic use (44.6%), local anesthetics (20.0%), and cyclooxygenase (COX) inhibitors (10.1%). Fatal SRsAs were reported in 9.5% (218/2304) of cases, the mean age of patients was 48.0 ± 16.7 years, and females accounted for 56.4% of cases. Pediatric SRsAs accounted for 3.9% of pediatric SRsDIAs and 5.8% of all SRsAs, with a mean age of 11.8 ± 4.5 years, and females acccounted for 51.9% of cases. Elderly SRsAs accounted for 2% of elderly SRsDIAs and 2.8% of all SRsAs, and the mean age was 73.0 ± 5.3 years, and females accounted for 43.5% of cases. ABs caused 40% of SRsAs in the elderly, 42.9% in children, and 50% of fatal SRsAs. (4) Conclusions: Our study revealed a relatively high proportion of anaphylaxis among SRs of drug-induced allergy. ABs were the most prevalent causative agents, especially in fatal SRsAs.

Adverse drug reactions in pregnant women: Do they differ from those in non-pregnant women of childbearing age?

Pharmacoepidemiological research in pregnant women has focused on adverse drug reactions for the course of pregnancy or for the unborn child, but little is known on the risks for the mother. We reported the results of a study that compared adverse drug reactions in pregnant women with non-pregnant women of childbearing age, and investigated whether which types of adverse reactions were more often reported in pregnant women and which drugs were more often involved. This study was carried out in the French pharmacovigilance database (BNPV). We compared adverse drug reactions reported between 1 January 2010 and 31 December 2019 in pregnant women with those reported in of non-pregnant women of childbearing age. We cross-matched each pregnant woman with three non-pregnant women of childbearing age according to geographic area, age and year the adverse reaction was reported. Data analysis revealed that serious adverse reactions were more frequently reported in pregnant women, including anaphylactic reactions. Other adverse reactions including tachycardia, hypotension and hepatic injury were also more frequent in pregnant women than in non-pregnant women of the same age. This could be explained by physiological changes in pregnancy that lead to greater sensitivity to certain adverse reactions. Some drugs, such as phloroglucinol, metoclopramide, iron, atosiban and nifedipine, were more frequently involved in adverse reactions in pregnant women. These drugs are specifically used during pregnancy, which may explain why they are over-represented in adverse reactions. This is the first comparative descriptive study on drug adverse reactions in pregnant women. Specific epidemiological and pharmacokinetic studies are necessary to confirm these results and better understand the differences observed to improve the monitoring of pregnant women exposed to certain drugs.