INTRODUCTION: The Pendred syndrome (PS) is an autosomally recessively inherited 
disease. Its diagnosis requires identification of the classical triad of 
symptoms, including hypoacusis, thyroid goitre and iodine organification defect 
in the thyroid, which may lead to thyroid functional disorders of 
hypothyroidism. SP is accompanied by anatomical anomalies. The objective is the 
hearing and balance system evaluation and the analysis of the inner ear 
structure and also the assessment of the function and structure of thyroid 
gland.
MATERIAL AND METHODS: For the research four families were qualified, 7 persons 
with PS, 12 persons altogether. In all the patients the anamnesis in the form of 
a questionnaire and laryngological examination were performed. It was followed 
by pure tone, speech and impedance audiometry and brainstem response testing as 
well. ENG was also conducted. Patients with hearing loss were subjected to 
magnetic resonance of temporal bone. For the whole group thyroid hormones levels 
and iodine organification in the thyroid identified in a test with potassium 
perchlorate were measured and also USG and scyntography were conducted.
RESULTS: In audiological examination in 3 cases deafness, in 2 cases profound 
hypoacusis and in 2 mild hypoacusis were recognised. In the group in 2 patients 
the hypoacusis was of a mixed type. In radiological assessment the labirynth 
showed anatomical anomalies in the form of enlargement of the vestibular 
aqueduct and the endolyphatic sac, yet in 3 patients the anomalies also 
concerned the structure of cochlear and semicircular canals. Endocrine 
examination showed hypothyroidism in 5, its subclinical form in 1, diffuse 
thyroid goitre in 4 and nodular thyroid goiter in 2 cases.
CONCLUSIONS: A complex clinical evaluation: endocrine and audiological, together 
with radiological diagnostic imaging, supported by molecular studies of SLC26A4 
gene, are the procedures, necessary for complete and accurate diagnosis of PS 
and EVAS.