What are the common symptoms of Klinefelter syndrome?

Klinefelter syndrome is a chromosomal disorder caused by an abnormal number of chromosomes. Its common symptoms mainly include: 1. Poor development of male secondary sexual characteristics:表现为 small and firm testes, with volume only one-third that of normal males or length less than 2 cm; low sexual function; sparse or completely absent facial, pubic, and axillary hair. 2. Body features: patients are typically tall with relatively long limbs. The lower body grows faster than the upper body and trunk, resulting in a longer lower body compared to the upper body. 3. Skin and voice: skin is smooth, voice is high-pitched and similar to that of females; more than half of patients exhibit gynecomastia (breast development). 4. Intelligence and mental health: some patients may have mild to moderate intellectual disability, psychiatric abnormalities, or a tendency toward schizophrenia. 5. Complications: may be associated with other conditions such as pulmonary diseases (emphysema, chronic bronchitis), varicose veins, diabetes, etc.