A follow-up survey of patients with acquired angioedema due to C1-inhibitor deficiency

BACKGROUND

Acquired angioedema due to C1-inhibitor deficiency (C1-INH-AAE) is a rare form of bradykinin-mediated angioedema. It is diagnosed by complement testing; its treatment consists of the management of angioedema (AE) attacks and of underlying disease.

OBJECTIVE

Evaluate the results of the clinical follow-up of patients with C1-INH-AAE.

METHODS

Between 1999 and 2020, 3938 patients with angioedema were evaluated, and 17 diagnosed with acquired C1-INH deficiency were followed-up.

RESULTS

Mean age of the 17 patients was 61 years at diagnosis. In 33%, ACE inhibitors provoked AE attacks. Autoantibodies against C1-INH were detected in 10 patients at diagnosis and in a further patient during follow-up. The AE attacks involved the skin in 70.6%, the upper airways in 41.2% and the tongue/lip in 52.9% of patients. Twelve of the 17 patients had an underlying condition, mainly (n = 11) lymphoproliferative disease. In 10 patients diagnosed with a haematological disorder, AAE symptoms preceded the onset of the latter. One patient has not experienced an AE attack since diagnosis. Twelve patients were treated for angioedema attacks, and 32% of the attacks required acute treatment. PdC1-INH was used to relieve AE attacks, and rituximab for the treatment of underlying disease (in six patients). Six patients had multiple AE attacks before any treatment. The symptom-free period increased in five patients after the on-demand administration of pdC1-INH concentrate and following treatment of the underlying disease in two patients.

CONCLUSION

Early diagnosis of C1-INH-AAE and underlying disease is indispensable to reduce disease burden by introducing appropriate, individualized treatment and regular follow-up.

The relationship between anxiety and quality of life in children with hereditary angioedema

BACKGROUND

The severe life-threatening characteristics of hereditary angioedema (HAE) with C1-inhibitor deficiency (C1-INH-HAE) can affect anxiety levels among pediatric patients. This emotional burden together with the physical restrictions of C1-INH-HAE may decrease children's health-related quality of life (HRQoL).

OBJECTIVES

(i) To compare anxiety state and trait between children with C1-INH-HAE and healthy controls; (ii) to examine the relationship between the level of anxiety of children with C1-INH-HAE, their disease activity/affected sites and their HRQoL; and (iii) to predict the HRQoL of children with C1-INH-HAE based on their anxiety level and disease activity/affected sites METHODS: Thirty-three children with C1-INH-HAE (aged 5-18 years) and 52 healthy controls were recruited from Israel and Hungary. All children completed the State-Trait Anxiety Inventory for Children (STAIC), the Pediatric Quality of Life Inventory (Peds-QL) demographic questionnaire and a disease activity and site questionnaire . Disease activity was defined as the number of attacks in last year.

RESULTS

Both anxiety state and trait were significantly higher among children with C1-INH-HAE as compared to the controls (44.74±10.56 vs 38.76±10.67, P<.01, 29.21±5.16 vs 25.23±4.09, P<.001 in comparison). Significant differences were found between C1-INH-HAE patients with HAE attacks, asymptomatic C1-INH-HAE patients, and healthy controls in both anxiety state (F_56,2 =4.69, P=.001) and trait (F_56,2 =9.06, P<.0001). A higher anxiety trait was correlated with the number of angioedema-affected sites (r=.52, P=.003). The presence of HAE attacks and higher anxiety trait predicted a lower HRQoL in children with C1-INH-HAE.

CONCLUSIONS

C1-INH-HAE children have higher anxiety trait and state, which correlate with reduced HRQoL domains.

Risk of thromboembolism in patients with hereditary angioedema treated with plasma-derived C1-inhibitor

BACKGROUND

Plasma-derived C1-inhibitor (C1-INH) concentrates (pdC1-INH) have been used as safe and effective treatments for hereditary angioedema with C1-INH deficiency (C1-INH-HAE) for >30 years. Notwithstanding this, sporadic reports and a study into the high-dose therapy of neonates with C1-INH concentrate administered in an off-label indication raised concerns that this drug might increase the risk of thromboembolism.

OBJECTIVE

To investigate the incidence of thromboembolism and the background of the risk factors related to treatment with pdC1-INH.

METHODS

Our retrospective cohort study of 144 patients with C1-INH-HAE compared the incidence of thromboembolism and its risk factors in patients who received pdC1-INH with those who did not receive pdC1-INH as well as with those treated with danazol or with tranexamic acid.

RESULTS

During the observation period (29 years), 104 of the 144 subjects received pdC1-INH. The average dose per treatment was 573.59 IU. None of the patients used an indwelling central venous catheter. Multiple risk factors for thromboembolism were identified in 93 of the 104 patients treated with pdC1-INH. The incidence rate of thromboembolism was 0.0019/100 person-years in patients treated with pdC1-INH, whereas it was 0.0211/100 person-years in the not-treated group.

CONCLUSION

Our cohort study did not find any evidence for an increased risk of thromboembolism during treatment with pdC1-INH, despite the presence of multiple predisposing factors.