Impaired sense of smell comprises a wide range of pathological entities. In the differential diagnosis in particular sinonasal diseasemust be taken into account as well as diseases affecting the peripheral or central nervous system. In clinical practice they are encountered most often by the otorhinolaryngologist. Although these complaints are often underrated they may be caused by serious systemic disease. The author describes two patients with an impaired sense of smell diagnosed at the Comenius University Bratislava. In one case the impaired sense of smell was the first manifestation of Kallmann’s syndrome.

        Key words: impaired sense of smell, differential diagnosis, Kallmann’s syndrome.