RECURRENT ANGIOEDEMA IN SLE PATIENT

Abstract

TOPIC: Allergy and Airway TYPE: Medical Student/Resident Case Reports INTRODUCTION: The pathophysiology of angioedema is broad. It may be hereditary, idiopathic, or a reaction to a range of medications or allergens; there have been a few case reports describing recurrent angioedema in patients with autoimmune conditions such as systemic lupus erythematosus (SLE). We present the case of a patient with SLE who suffered from recurrent angioedema of the face, including lips, tongue, and throat, without urticaria, with normal C1-Inhibitor levels. CASE PRESENTATION: A 69-year-old female with a history of SLE and recurrent angioedema presented with progressive swelling of eyes, lips, and tongue for one week. She did not consume angiotensin-converting enzyme inhibitors and reported no medication changes or exposure to unknown substances. Physical examination revealed facial, periorbital, and tongue edema with respiratory distress. Initial lab work was unremarkable. Histamine blockers and steroids were immediately administered, and she was intubated due to respiratory compromise. Racemic epinephrine was also initiated, and tracheostomy was performed for definitive airway management. Workup for infection was unrevealing. C1-Inhibitor, CH50, and C4 levels were not deficit. Once her respiratory status was stabilized, she was discharged to a long-term care facility. DISCUSSION: Angioedema, defined as localized subcutaneous or submucosal swelling due to the extravasation of fluid into interstitial tissues, maybe mast cell-mediated or kinin-mediated. The former is often associated with urticaria and is triggered by an allergic reaction or medications. At the same time, the latter occurs in the absence of a specific trigger and is associated with hereditary C1-Inhibitor deficiency or dysfunction. Our patient had normal C1 esterase inhibitor levels, rendering the diagnosis of hereditary angioedema less likely. Furthermore, she reported taking no medications known to cause angioedema and had not been exposed to any new allergens before the presentation. Literature states that patients with SLE characteristically exhibit reduced levels of components of the classical complement pathway. The defect can either originate from a lymphoproliferative disease that catabolizes C1-Inhibitor or circulating antibodies that inactivate C1-Inhibitor. However, our patient did not fulfill the above-mentioned criteria. Even though similar cases have been reported in the literature, the occurrence is still scarce. CONCLUSIONS: SLE has rarely been associated with recurrent angioedema. The pathophysiology of such is unclear. Our patient's late age of presentation and lack of family history of angioedema favored SLE as the independent risk factor for angioedema. Cl-inhibitor dysfunction in SLE is heterogeneous and distinct from that reported in either hereditary or acquired angioedema. Hence, more work needs to be done for early recognition and prompt prevention. REFERENCE #1: Dunckley H, Gatenby PA, Hawkins B, Naito S, Serjeantson SW. Deficiency of C4A is a genetic determinant of systemic lupus erythematosus in three ethnic groups. J Immunogenet. 1987 Aug-Oct;14(4-5):209-18. doi: 10.1111/j.1744-313x.1987.tb00383.x. PMID: 3502648. REFERENCE #2: Alsenz J, Bork K, Loos M. Autoantibody-mediated acquired deficiency of C1 inhibitor. N Engl J Med. 1987 May 28;316(22):1360-6. doi: 10.1056/NEJM198705283162202. PMID: 3494945. REFERENCE #3: Thong BY, Thumboo J, Howe HS, Feng PH. Life-threatening angioedema in systemic lupus erythematosus. Lupus. 2001;10(4):304-308. doi:10.1191/096120301680417011 DISCLOSURES: No relevant relationships by Asim Amjad, source=Web Response No relevant relationships by Zamara Hamid, source=Web Response No relevant relationships by Dan Kazmierski, source=Web Response No relevant relationships by Si Li, source=Web Response No relevant relationships by Pius Ochieng, source=Web Response No relevant relationships by NISHANT SHARMA, source=Web Response