Introduction: Hereditary Angioedema is a rare, autosomal dominant disorder characterized by episodes of cutaneous, subcutaneous tissue and submucosal swelling. So far, there are no effective biomarkers associated with increased number and severity of angioedema episodes. The role of D-dimer as a biomarker in this pathology is unknown.
Methodology: We conducted a cross-sectional, observational, retrolective study of ISSSTE patients, attended at the Clinical Immunology and Allergy Service of the CMN 20 de Noviembre, with a proven diagnosis of Hereditary Angioedema type 1. A survey was conducted where the number and characteristics of angioedema attacks suffered in the last 4 weeks were identified and the results of: D-dimer, absolute neutrophil count, neutrophil/lymphocyte ratio, C4 levels, CRP and ESR. Data collection was performed from March 1 to July 1, 2023. Variables were analyzed and mean, standard deviation, frequencies, percentages were obtained, and variables were correlated by Pearson’s P and a simple linear regression model was performed to assess correlation strength.
Results: 6 patients were included in the study (n=6), of which 5 were female gender (83.3%), mean age in the study was 58.3 years, mean BMI was 28.4 kg/m2. The mean number of angioedema attacks in the last 4 weeks was 2.5. No correlation was found between D-Dimer elevation with the number of angioedema attacks (p=0.088), nor was there a correlation with the neutrophil/lymphocyte ratio (p=0.66), nor with the CD4/CD8 lymphocyte ratio (p=0.544), nor with CRP levels (p=0.082) or ESR (p=0.257). However, a strong negative correlation was found between serum C4 levels and the number of angioedema episodes (p=0.032).
Conclusions: Increased D-Dimer levels did not correlate with increased number of angioedema episodes, however, decreased C4 levels correlated with increased number of angioedema episodes. Interestingly, all patients presented alterations in the CD4/CD8 ratio, suggesting immune dysregulation.