Hypopituitary disease refers to the pituitary's inability to produce any single pituitary hormone or failure to produce a combination of multiple pituitary hormones.
HGH deficiency is a growth disorder that results in shorter than normal stature for age, particularly in adolescents. Without intervention, patients rarely exceed four feet in height and can be much smaller. In most people, the pituitary gland produces large amounts of human growth hormone throughout childhood and with the start of puberty, with a significant drop in production at age 25. With HGH deficiency, instead of experiencing a normal growth, the child grows slowly and does not experience the typical growth spurt with puberty.
HGH deficiency should not be confused with dwarfism. In dwarfism, the torso is more or less normal size, with only the arms and legs being foreshortened. Giving HGH to a dwarf would be catastrophic as it is the formation of bones that is abnormal in dwarfs; they produce sufficient HGH. Such treatment might result in acromegaly. In hypopituitary patients, the torso is also of below average size, and the proportions of such patients are similar to others with normal growth patterns.
ACTH deficiency, also called secondary hypoadrenalism, is an adrenal disorder that results in failure of the adrenal glands to produce cortisol (and often failure to produce mineralcorticol steroids and DHEA as well). Symptoms are varied and seemingly unconnected. Unless there is also HGH deficiency, ACTH deficiency is generally not recognized until after age 25, when the production of HGH drops significantly. After 25, symptoms include sudden and unintentional weight loss, adult onset allergies and diarrhea/GI pain (all due to an overactive inflammation response), low blood pressure, and cold sensitivity to name a few. ACTH deficiency is different from Addison's Disease in that it does not include skin pigmentation symptoms. Contrary to Addison's, people with ACTH deficiency tend to have difficulty losing tans.
TSH deficiency, also called secondary hypothyroidism, is a thyroid disorder that results in the thyroid not producing T4 and sometimes the inability of the body to properly convert T4 into T3. Symptoms are varied and may include fatigue, depression, unintentional weight gain, cold intolerance, excessive sleepiness and/or exhaustion, dry and/or coarse hair, hair loss, constipation, dry skin, muscle cramps, vague aches and pains, and pitting edema (swelling; typically around the ankles and hands). If hypopituitarism is the diagnosis, hypoadrenalism must be treated first, before treating hypothyroidism.
FSH/LH deficiency, also called secondary hypogonadism, is a gonad disorder in which the testes/ovaries fail to produce testosterone/estrogen. People with this condition will not experience puberty normally and will have androgynous features without hormone replacement.
ADH deficiency, also known as central diabetes insipidus, is a kidney disorder in which the kidneys are unable to conserve water when filtering the blood. The major symptoms of diabetes insipidus are excessive urination and extreme thirst. Left untreated, diabetes insipidus can cause dehydration and/or water intoxication, both of which can result in death.
Hypopituitary disease is caused by damage to the pituitary gland from any number of sources, including but not limited to: severe head trauma, breech birth, complications of pregnancy, tumors (cancerous and non-cancerous), irradiation of the pituitary, or infection. Often the direct cause is not known.