E024 A pregnant woman with vasculitis and a new rash

Abstract Background/Aims A 41-year-old pregnant woman at 16 weeks of gestation was followed-up in the combined obstetric and rheumatology clinic as she had a history of eosinophilic granulomatosis with polyangiitis (EGPA) and two previous miscarriages at first trimester. Her vasculitis was well-controlled with a baseline daily dose of prednisolone 7.5mg. Methods During her pregnancy, she started on vaginal progesterone by the IVF (In Vitro Fertilization) team for pregnancy support following a vaginal bleed. During her second review in clinic, she complained about a widespread pruritic rash for the last 3 weeks. She had already been seen by her GP who prescribed her emollients without any improvement. On examination, the active lesions looked urticarial and were tender. There was also residual hyperpigmentation. The lesions persisted for more than 24 hours before spontaneous resolution. Cutaneous vasculitis was suspected based on the duration of the rash more than 24 hours, the hyperpigmentation, tenderness, and the history of EGPA. Otherwise, she was well in herself with no symptoms of active vasculitis and no recent infections. Therefore, prednisolone was increased to 15mg daily and loratadine was given for the pruritus. Her repeat blood tests were reassuring with negative ANCA, normal C3 and C4, CRP, and eGFR. Results During her early follow-up, the rash was the same despite the higher dose of steroids and she volunteered that the rash is worse in the morning and at night. Autoimmune progesterone dermatitis (AIPD) was considered then. AIPD is a rare autoimmune hypersensitivity reaction to endogenous or exogenous progesterone. AIPD varies greatly from patient to patient and can present as urticaria, eczema or vesiculobullous eruptions. Urticarial or EGPA vasculitis, and urticaria would have improved with steroids. Furthermore, she did not have any symptoms suggestive of systemic vasculitis and the relevant blood tests were also normal. Of note, the rash was worse in the morning and at night, which corresponded to the time of vaginal exposure to progesterone. The patient stopped the progesterone pessaries after discussion with the obstetrician. The rash improved gradually and resolved in five days, confirming the diagnosis of AIPD. Conclusion The rash could have been mistaken for urticaria or vasculitis. Consequently, the patient may have had unnecessarily antihistamines and steroids during pregnancy with all relevant side effects, such as gestational diabetes. In November 2021, NICE recommended vaginal progesterone in women who experience bleeding in early pregnancy and have a history of miscarriage as it slightly reduces the risk of a further miscarriage. The new guidelines suggest that more pregnant women will use topical progesterone during pregnancy who may develop AIPD. This means that we are going to see more pregnant women in the rheumatology clinic with AIPD and the rheumatology community should be aware of this entity. Disclosure A. Madenidou: Grants/research support; Janssen. H. Kither: None. I. Bruce: Consultancies; AstraZeneca, GSK, Eli Lilly, and UCB. Honoraria; AstraZeneca, GSK, and UCB. Grants/research support; AstraZeneca, GSK, and Janssen.