Causes for smell impairment in patients with hereditary angioedema

Background:

The aim of this study was to examine the olfactory function of patients with hereditary angioedema (HAE) and to investigate whether genetic mutations, pre-existing conditions, quality of life, drug intake or specific laboratory values affect the sense of smell.

Methods:

Olfactory function of 31 patients with HAE and a sex- and age-matched control group was examined using the 3-stage “sniffin' sticks”-test (TDI: threshold, discrimination, identification). All study participants had to fill in an ENT-specific questionnaire (RSOM-31) and one for quality of life (SF-36). Furthermore nasal endoscopies were performed. Blood samples of 30 patients clinically diagnosed with HAE were collected and genetic analysis (PCR and MLPA) were performed to detect mutations in the SERPING 1 gene. An array-based gene expression analysis of olfactory receptor genes on chromosome 11 was carried out in these patients.

Results:

Patients with HAE suffered significantly more often from hyposmia than healthy controls (p < 0.01). The disease duration correlated negatively with the overall TDI-result and the olfactory threshold. Subjects with hyposmia had significantly lower levels of C1-inhibitor-concentration (p = 0.026), C1-inhibitor-activity (p < 0.01) and C4 (p < 0.01). Comorbidities, quality of life, drug intake and clinical findings in ENT examinations did not significantly differ between HAE patients and healthy controls and had no influence on the TDI-results. The genetic analysis showed no mutations of olfactory receptor genes on chromosome 11.

Conclusion:

This study corroborated previous evidence suggesting a decreased sense of smell in patients with HAE. Neither ENT-specific diseases, nor genetic alterations seem to be the cause of an impaired sense of smell in patients with HAE.

Publikationsverlauf

Publikationsdatum:
18. April 2018 (online)