[Diagnosis of hypothyroidism in the adult]

Hypothyroidism is a common endocrine disease, specially in women after the age of fourty. The clinical manifestations may be insensitive, aspecific or absent, which may impair diagnosis. Clinical, anamnestical and biological features may lead to a diagnostical suspicion that needs to be confirmed by a determination of serum TSH. Serum TSH determination allows the early recognition of subclinical hypothyroidism. However the signification of this moderate increase in TSH level is controversial, and uncertainty remains over the benefits of treating such patients yielding slightly elevated TSH concentration. Hypothyroidism is usually caused by a primary autoimmune thyroid disease, and seldom due to central hypothalamic or pituitary disorder.