(26) Delayed hypersensitivity reaction to Mirena IUD

Background: Immune-mediated hypersensitivity reactions have been documented in response to endogenous and exogenous progesterone including the levonorgestrel-containing intrauterine device (IUD), with reactions ranging from urticaria to angioedema and anaphylaxis. Typically, reactions to progesterone have been described as acute or chronic in onset with long lasting symptoms. This case will discuss a unique timeline of onset and symptom progression.

Case: A 22-year-old patient presented to the ED with 3 days of worsening itching, burning and tingling. The patient had been seen that morning by her Pediatric Adolescent Gynecologist (PAG) for follow up 6.5 weeks after placement of a Mirena IUD for long-term management of endometriosis. She had been on the oral contraceptive pill Lo Loestrin for over one year, while IUD in situ. PAG decided not to remove IUD since symptoms were still mild, pending input from allergist for evaluation of alternate causes. Symptoms progressed throughout the day to include upper and lower extremity swelling bringing her to the ED, at which time she was discharged with antihistamines. However, swelling continued to worsen and she returned to ED 24 hours later. Physical exam was notable for maculopapular erythema and edema to the face palms and soles of feet. IUD was removed immediately, and patient was treated with Solu-Medrol and Benadryl with symptomatic improvement. She was discharged to home with prednisone, and symptoms resolved over the next 3 days. Follow up with outpatient immunologist determined case to be consistent with delayed hypersensitivity reaction in response to exogenous progesterone from the IUD. She has had no recurrence of symptoms since the IUD was removed.

Comments: While there is no absolute confirmation that the IUD was the sole cause of her acute pruritus and edema, there is a strong correlation between symptom onset and resolution relative to IUD insertion and removal. Documented cases of hypersensitive reactions in response to progesterone exposure have a timeline that generally fall within 2 categories. First is acute symptom onset appearing within several days of IUD insertion or second, chronic symptoms appearing months later and lasting years. This case illustrates an unusual timeline of progesterone-based IUD reaction with acute onset of symptoms 6 weeks after insertion progression within days to severe symptoms. Recognizing that an allergic reaction to a Mirena IUD can occur in this timeline and escalate to potentially life-threatening anaphylaxis is crucial since removing the Mirena IUD allergen is the cure.