Smell Disorders: A Study of 132 Patients from the First Smell and Taste Clinic of Thailand
Apichai Kaolawanich MD*, Paraya Assanasen MD*, Prayuth Tunsuriyawong MD*, Chaweewan Bunnag MD*, Pongsakorn Tantilipikorn MD*
Affiliation : * Department of Otorhinolaryngology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Objective : To investigate types and possible causes of smell disorders in patients who attended the Smell and
Taste Clinic, Siriraj Hospital.
Material and Method: Medical records of patients with smell disorders who attended the Smell and Taste
Clinic, Siriraj Hospital between July 2002 and August 2005 were reviewed for gender, age, duration of
complaint, severity (hyposmia or anosmia), and previous medical illnesses (e.g. upper respiratory tract
infection (URI), head injury, sinonasal problems, etc). All patients had complete physical examination, nasal
endoscopy, and phenyl ethyl alcohol (PEA) olfactory threshold test.
Results : One hundred and eighty eight patients’ medical records were reviewed. Smell disorders were
confirmed in 132 cases (male = 58, female = 74). Nearly an equal number of anosmia and hyposmia cases were
found (50.8% and 49.2% respectively). Possible causes of smell disorders were categorized as follows: sinonasal
disease (SND) (66.7%), head injury (12.1%), idiopathic cause (10.6%), URI (6.8%), congenital cause (3%),
and others (0.8%). SND was the most common cause of smell disorders despite different age groups and
duration of smell disorders. PEA test scores were higher in head injury and idiopathic groups compared with
those in SND and post URI groups.
Conclusion : The present data showed that SND was the major cause of smell disorders in every age group and
in each duration group followed by head injury, idiopathic cause, and URI respectively. Therefore, nasal
endoscopy is highly recommended for every patient with smell disorders.
Keywords : Anosmia, Nasal endoscopy, Hyposmia, Olfaction disorders, Phenylethyl alcohol, Smell disorders
