Impaired sense of smell in hereditary angioedema

Hereditary angioedema (HAE) is an autosomal-dominant disorder resulting from C1-inhibitor (C1INH) deficiency. Smell impairments were found in patients affected with systemic lupus erythematosus (SLE), that, similarly to HAE, is characterized by the activation of the classical complement pathway with C4 consumption.

30 patients with HAE were evaluated for olfactory functions using the 3-stages Sniffin'-Sticks kit: threshold, discrimination, and identification (TDI scores).

A decrease in olfactory function was found in HAE patients. Anosmia was present only in patients with HAE (3%) who also exhibited more frequently hyposmia (53% vs 3% for controls).

Complement levels were reduced in HAE.

Impaired sense of smell was found in patients with HAE. The reduction in olfactory function in these cases correlated with complement C4 and CH50 levels.

References:

Perricone C, Agmon-Levin N, Shoenfeld N, de Carolis C, Guarino MD, Gigliucci G, Milana I, Novelli L, Valesini G, Perricone R, Shoenfeld Y. Evidence of impaired sense of smell in hereditary angioedema. Allergy 2010; DOI: 10.1111/j.1398-9995.2010.02453.x.

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