Purpose: Acute edema of the head and neck region may lead to life-threatening dyspnea and require quick and targeted treatment. They can be subdivided in bradykinin- and histamine-mediated swellings, which require treatment with different classes of pharmaceuticals. Clinical pathways for differential diagnoses do not exist so far, although it is known that early treatment is decisive for faster symptom relief and reduced expression of the swellings. Aim of the study was the creation of a clinical algorithm for identification of bradykinin-mediated angioedema.
Methods: 188 patients that presented to our outpatient department between 2010 and 2016 with an acute, non-inflammatory swelling of the head and neck region were included in our retrospective study. All available anamnestic and clinical parameters were obtained from patient files. Parameters showing significant differences between the two groups were included in our score. Utilization of the Youden's index allowed determination of an optimal cut-off value.
Results: 76 patients could be assigned to the histamine and 112 patients to bradykinin group. The following parameters were included in our score: age, dyspnea, itching or erythema, glucocorticoid response and intake of ACEi/AT-II blockers. The cut-off value is set at three points. The proposed score yielded a sensitivity for identification of bradykinin-mediated angioedema of 96%, a specificity of 84%, a positive predictive value of 91% and a negative predictive value of 93%.
Conclusions: Utilization of the proposed score allows quick and reliable assignment of patients to the correct subgroup and thereby reduces time for treatment.
Keywords: ACE inhibitor; Angioedema; Bradykinin; Differential diagnosis; Histamine; Urticarial.