History
The symptomatology depends on the disease causing the low or high follicle-stimulating hormone (FSH) levels and varies between men and women.
In men presenting with low FSH levels leading to secondary hypogonadism or high FSH levels resulting from primary hypogonadism, the history reveals erectile dysfunction, decreased libido, infertility, and low energy.
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In those with hyperprolactinemia, galactorrhea and/or gynecomastia may be present.
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Depending on the timing of the FSH abnormality, further questioning may indicate ambiguous genitalia at birth or a failure to undergo or complete puberty.
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Anosmia suggests Kallmann syndrome.
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Visual abnormalities, headaches, and other hormonal deficiencies suggest a mass or a destructive process involving the pituitary.
In men presenting with high FSH levels due to a gonadotroph adenoma, symptoms result from the mass effect (eg, headaches, visual impairment, hormonal deficiencies). However, erectile dysfunction and infertility may occur secondary to low LH levels caused by compression of the normal gonadotroph cells.
In women presenting with low FSH levels or high FSH levels secondary to ovarian failure, manifestations include oligomenorrhea or amenorrhea.
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Galactorrhea may be present in the setting of high prolactin levels.
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Symptoms of other pituitary hormone deficiencies may also be evident if a mass or a destructive process involves the pituitary gland.
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Women may have primary or secondary infertility.
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In women with ovarian failure, other symptoms may include hot flashes, sleep disturbance, mood swings, depression, vaginal dryness and dyspareunia, urinary incontinence, and urinary tract infections.
In women with high FSH levels from a gonadotroph adenoma, symptoms are frequently due to mass effect (eg, headaches, visual changes, hypopituitarism). However, a high FSH level may also lead to ovarian hyperstimulation in premenopausal women, with multiple ovarian cysts [2] and a thickened endometrium; this leads to disturbed menstrual cycles, ie, oligomenorrhea or amenorrhea.
Physical
The physical examination findings also depend on the disease that underlies the abnormal follicle-stimulating hormone level. The following important points must be remembered.
In men presenting with hypogonadism, findings depend on the timing of onset during life and on the duration of testosterone deficiency.
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In utero (if testosterone deficiency occurs in the first trimester): Male sexual differentiation is incomplete, resulting in pseudohermaphroditism. Complete lack of testosterone results in female external genitalia. Incomplete testosterone deficiency causes partial virilization with ambiguous genitalia.
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In utero (if testosterone deficiency occurs after the first trimester): Normal male sexual differentiation occurs but with micropenis/cryptorchidism at birth.
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Before puberty: Testosterone deficiency results in delayed and incomplete puberty.
Small testes (< 2.5 cm [normal = 4-7 cm])
Short phallus
High-pitched voice
Decreased muscle mass
Decreased body hair
Delayed bone age
Eunuchoid skeletal proportions: Eunuchoidism is a lack of testosterone during puberty that causes a delay in epiphyseal closure so that the continued presence of GH results in increased length of the long bones (ie, arm span greater than height, lower body segment [heel to pubis] longer than upper body segment [pubis to crown]).
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After puberty
Normal skeletal proportions and penile length
Soft testes
Decreased strength and muscle mass
Decreased rate of hair growth (facial, pubic, axillary)
Gynecomastia
In women presenting with hypogonadism (oligomenorrhea or amenorrhea), physical examination findings may include hirsutism and/or masculinization (eg, frontal balding, clitoromegaly, increased muscle mass) only if an excess of androgens is present, which is not frequent. The examination may reveal stigmata of Turner syndrome (eg, short stature, webbed neck, shield chest, wide carrying angle of the arms), short fourth metacarpals, cardiovascular anomalies (coarctation of aorta, bicuspid aortic valve), or evidence for other endocrine deficiencies or autoimmune diseases (eg, Addison disease, vitiligo, Hashimoto thyroiditis).
In men and women with pituitary macroadenomas, visual-field examination findings may be abnormal. Other signs of hypopituitarism may also be detected upon examination.
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Human G protein-coupled receptor 54 (GPR54) receptor model. Mutations identified in patients with idiopathic hypogonadotropic hypogonadism are indicated.
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This is a frequently sampled serum luteinizing hormone (LH) profile in a male patient with Kallmann syndrome (KS), compared with that in a healthy individual. A lack of LH pulsatility is seen in the former.
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Magnetic resonance imaging (MRI) scan of pituitary macroadenoma.
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Adolescent male with Klinefelter syndrome who has female-type distribution of pubic hair, as well as testicular dysgenesis.
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Hypoplastic right hemiscrotum in a patient with an undescended right testis.
