Mother’s Diagnosis of Daughter’s HAE Highlights Need for Clinicians to Listen to Patients, Families

The mother of a 28-year old pregnant woman suspected her daughter had hereditary angioedema after doing an internet search while the daughter was hospitalized. The diagnosis was quickly dismissed by clinicians, who considered it extremely unlikely, but it later proved to be correct.

This case report highlights the importance of considering all possibilities and listening to patients and their relatives. It also shows why clinicians should not discard the differential diagnosis (the process of ruling out conditions that share similar symptoms) of a rare disease with relatively common symptoms solely based on probability.

The case report, “Hereditary angioedema: a mother diagnosing her child using Google as a diagnostic aid,” was published in BMJ Case Reports.

Hereditary angioedema (HAE) with C1 inhibitor deficiency is a rare and potentially life-threatening genetic disorder characterized by sudden and recurrent episodes of swelling in the deepest layers of the skin.

Swelling can occur anywhere, but is often seen in the face, tongue, hands, feet, gastrointestinal (GI) tract, genitalia, and upper airways.

The disease is caused by genetic mutations in the SERPING1 gene, leading to lower levels of C1 inhibitor ( type 1) — or a dysfunctional C1 inhibitor whose levels remain normal or elevated (type 2).

Attacks can be triggered by several factors, including stress, menstruation, oral contraception and pregnancy. Because HAE is extremely rare and the symptoms resemble other types of angioedema or other medical conditions, HAE patients often are misdiagnosed, especially in an emergency setting, and fail to receive proper treatment.

In this case report, researchers described the clinical case of a 28-year old Caucasian woman diagnosed with HAE type 1 during her second pregnancy, nearly 20 years after experiencing her first symptoms.

During childhood, she started experiencing severe abdominal pain that worsened when, at age 17, she began taking oral contraceptives. In 2011, during her first pregnancy, the patient experienced abdominal attacks along with swelling of her right arm.

In 2016, during her second pregnancy, she experienced abdominal attacks similar to those she felt during her first pregnancy. In the fourth month of gestation, she had to be hospitalized because of extreme upper lip and facial swelling. Physicians administered an intravenous antihistamine in an attempt to control tissue swelling, but it had no effect.

While the woman remained in the hospital, her mother began to suspect her daughter could be suffering from HAE after doing an internet search. They discussed the diagnosis with the clinicians, who dismissed it because of the rarity of the condition.

After leaving the hospital and having blood tests to measure the levels and function of C1 inhibitor and genetic screenings to look for mutations in the SERPING1 gene, the woman was diagnosed with HAE type 1 by her general practitioner.

“This case illustrates the importance of considering rare differential diagnoses to common symptoms. Healthcare professionals should be aware of the HAE diagnosis and the necessity of referring patients to a HAE center or to a relevant specialist, as soon as the HAE diagnosis is considered. Diagnostic delay can be reduced when awareness of HAE is increased among physicians and other healthcare personnel, who will meet these patients in the emergency care setting,” researchers stated.