Immunity in pregnancy is characterized by a shift from cell-mediated immunity (Th1) to humoral immunity (Th2) and is associated with a reduction in fetal demise/abortion. The upregulation of the Th2 response is similarly seen in atopic diseases which are associated with reduced fertility. It is, therefore, not surprising that pregnancy worsens AD severity. For this reason, adequate control of AD in pregnancy is warranted and may reduce the risk of severe complications such as eczema herpeticum, bacterial infections, and improve quality of life with reduced psychosocial comorbidities11–13.
The current cornerstones of AD treatment in pregnancy include topical corticosteroids, topical calcineurin inhibitors, and narrowband ultraviolet B (UVB). In the setting of refractory disease, systemic cyclosporine or glucocorticoids can be used as alternative therapies for long term disease control, although the risk of low birth weight in neonates with maternal cyclosporine or long term steroid used must be considered3,9.
Biologic therapies in pregnancy continues to gain traction especially in the management of inflammatory bowel disease, and rheumatoid arthritis where the use of tumor necrosis factor (TNFα) inhibitors is generally considered safe in the first 2 trimesters due to the negligible transfer of maternal antibodies during this period10. With regards to AD, there remains a paucity of data with only 2 case reports reporting the use of dupilumab in pregnancy. Both case reports demonstrated favorable maternal and fetal outcomes.11,14The effects of dupilumab on breastfeeding infants is unclear and, therefore, is not currently recommended in lactating women8. Similarly, the effects of dupilumab on the neonatal immune system are uncertain and the potential for altered newborn immunity exists10. For this reason, the administration of live vaccines should be delayed for at least 6 months post delivery10. In this case, the patient demonstrated well controlled AD despite not being on dupilumab maintenance therapy.
This case report adds to current literature regarding the use dupilumab in pregnancy. To our knowledge, this is the first case report of a pregnant patient with AD treated with dupilumab in Canada. Our case is the first to demonstrate symptom resolution without re-initiation of dupilumab in the postpartum setting with excellent maternal and fetal outcomes.