Which condition is a common pathological cause of hirsutism?

Polycystic ovary syndrome (PCOS) is a common pathological cause of hirsutism due to its association with elevated androgen levels, which are male hormones that can lead to increased hair growth in women. In PCOS, the ovaries may produce excessive androgens, which can result in symptoms such as irregular menstrual cycles, infertility, and hirsutism. The presence of these elevated androgen levels manifests as unwanted hair growth, particularly in areas where men typically develop hair, such as the face, chest, and back.

In contrast, conditions like Addison disease and hyperthyroidism may have hormonal imbalances but are not directly linked to the specific increase in androgens that triggers hirsutism. Addison disease involves adrenal insufficiency, leading to a deficiency in cortisol and aldosterone, while hyperthyroidism typically results in excess thyroid hormone, which affects metabolism but does not typically cause hirsutism. Alopecia refers to hair loss and does not contribute to the increased hair growth characteristic of hirsutism. Thus, PCOS stands out as the primary condition associated with hirsutism due to the direct influence of elevated androgens.