A 23-year-old pregnant woman (gravida 2, abortion/miscarriage 1, para 0) with a history of anxiety (treated with citalopram) and cocaine use (stopped before pregnancy) and no family history of swelling presented to hospital at 9 weeks gestation. She reported episodic abdominal pain and nausea, as well as vomiting and intermittent unilateral swelling of the hands and feet for the previous 2-4 days. An erythematous nonpruritic rash preceded her symptoms. During the pregnancy, she experienced 4 more episodes with similar symptoms, presenting to either her prenatal care provider or the emergency department. At each presentation, she was assessed for pregnancy complications and reassured that her symptoms would improve postpartum.
The patient delivered a healthy female infant at term by cesarean delivery under spinal anesthetic and was discharged on postpartum day 2. Eleven days postpartum, the patient presented with swelling and erythema at the cesarean delivery wound. She was diagnosed with cellulitis and managed with intravenous (IV) ceftriaxone, followed by oral antibiotics for 2 weeks with improvement. A wound culture grew Enterobacter cloacae. A few days later, she returned with abdominal pain and pronounced swelling of the left labia and right thigh. A computed tomography (CT) scan of the abdomen and pelvis showed inflammatory changes at the cesarean delivery site with no visible abscess, and nonspecific retroperitoneal inflammatory changes. Her symptoms progressed to include vomiting, diarrhea, abdominal distension and tenderness. She was tachycardic and volume depleted and did not respond to ondansetron and fluid bolus, prompting admission under obstetrics for potential wound infection. Wound examination identified incision breakdown with purulent discharge; wound swab returned polymicrobial flora and was considered nondiagnostic. Clostridioides difficile polymerase chain reaction (PCR) testing of stool was positive, but no toxin was detected. Repeat CT scan showed bowel wall thickening and edema involving the left mid small bowel, with moderate free fluid. Her symptoms were attributed to the wound and C. difficile infection, the infectious disease team recommended ceftriaxone and metronidazole, and she gradually improved over 1 week. She underwent vacuum-assisted closure of the wound and was given ranitidine for possible gastroesophageal reflux.
Over the next 9 months, the patient continued to have symptoms of abdominal pain, nausea, vomiting and episodic, migratory swelling, resulting in frequent presentations to health care providers (Figure 1 and Table 1). In total, she had 6 emergency department presentations and 1 hospital admission and saw 5 different specialists, including obstetrics and gynecology, internal medicine, 2 infectious disease specialists and gastroenterology. She underwent extensive investigations and various diagnoses were suggested (Table 1). Multiple specialists documented her episodes of swelling, but a diagnosis of angioedema was not considered, and no trials of therapies for possible histamine-mediated angioedema (Table 2) were initiated. The patient did not take any angiotensin-converting enzyme (ACE) inhibitor or exogenous estrogen that could have confounded the clinical presentations.
At 10 months postpartum, she was assessed in an outpatient infectious disease clinic, where C4 and C1 inhibitor (C1-INH) levels were ordered. Consistent with a diagnosis of hereditary angioedema (HAE), C1-INH functional assay and C4...