Abstract:

Objective

To explore the clinical characteristics of nadroparin-induced eosinophilia in perinatal women with pulmonary embolism and provide a reference for clinical drug safety.

Methods

Cases of perinatal patients diagnosed with pulmonary embolism who developed eosinophilia during treatment with nadroparin between 2020-2023 were collected.Basic patient information was extracted，including age，body weight，underlying disease，pulmonary embolism diagnosis timing，nadroparin dosage，comorbidities，baseline eosinophil count，time to onset of eosinophilia，peak eosinophil count，presence of skin symptoms，time for eosinophil count to return to normal level，and regression of adverse effects.

Results

A total of 8 perinatal women with pulmonary embolism experienced eosinophilia during the administration of nadroparin.The patients were aged 27 to 34 years and all were treated with nadroparin after diagnosis of pulmonary embolism without other concomitant medications.Eosinophilia was detected as early as 12 days post-dose，with a slightly higher basal eosinophil count （0.26×10⁹/L） than the other patients.Eosinophilia was detected as late as 70 days postdose，and this patient had the mildest adverse effect with a peak eosinophil count of 0.55×10⁹/L）.One patient reached the clinical diagnosis of severe eosinophilia with a peak eosinophil count of 5.31×10⁹/L.Three patients had accompanying skin symptoms，which disappeared after discontinuation of the drug.Seven patients had their dosage reduced，discontinued the drug，or changed their anticoagulation regimen after the eosinophil count increased.The eosinophil count returned to normal levels 2-114 days after drug withdrawal without other intervention measures.Among them，the eosinophil count of patients treated with reduced dosage continued to increase and then improved after drug withdrawal.Another patient did not adjust the treatment plan，and her eosinophils continued to rise，subsequent follow-up data were lost.

Conclusion

Nadroparin-induced eosinophilia in perinatal women with pulmonary embolism occurs within 10 weeks，and some patients may experience skin symptoms such as itchiness，which generally recover after drug discontinuation.When using nadroparin to treat perinatal patients with pulmonary embolism，clinicians should closely monitor eosinophil count changes to promptly detect and appropriately manage this adverse reaction.

Key words: Pulmonary embolism, Eosinophilia, Nadroparin, Perinatal women, Adverse reactions, Clinical characteristics