Hypopituitarism is an endocrine disorder, characterized by reduced emission of pituitary gland hormones. Pituitary gland produces 8 types of hormones, and if there is an insufficiency of all of them, the condition is referred to as panhypopituitarism. In majority of the incidents, it is caused by a tumor located in the pituitary gland or other parts of the brain. Symptoms and sings may vary, depending on which hormones are insufficient, and the common ones include weight loss, headache, infertility, anemia, fatigue and vision disorders. Treatment usually includes hormones replacement, which is done in order to restore their proper quantities, rather than fixing pituitary malfunctions. Features of the disease can be easily controlled, however, the therapy is often lifelong.
The pituitary gland is a small organ, which belongs to endocrine system and often cooperates with hypothalamus. Their task is to produce several hormones, which are controlling almost every aspect of human organism. Hypopituitarism is a gland malfunction, which further leads to insufficiency of one or more hormones. If all hormones are deficient, it is called as panhypopituitarism. Those types of endocrine disorders may disturb tissues growth and development, fluid balance, metabolism, sex features, fertility and many more.
Fortunately, hypopituitarism is a rare disorder. The worldwide annual prevalence is estimated to be around 4 incidents per 100,000 population, however, those numbers might be underestimated. Opposite disorder, causing increased hormones emission, is called as hyperpituitarism.
Hypopituitarism causes and symptoms
Excluding congenital hypopituitarism, which is extremely rare, there are several possible causes of the disease. As for now, the most common cause is a tumor (adenoma) located in the pituitary gland, which is responsible for over half of the incidents. They are usually benign (non-cancerous), and occasionally they can press on optic nerves, which leads to vision disorders. Another possible causes include other brain tumors, gland infections, radiation therapies and bad performed surgeries. What is more, the disease may also be triggered by traumatic brain injury.
Signs and symptoms might be mild, or even unnoticeable, for many years. Hypopituitarism is developing slowly, and symptoms will vary, depending on the insufficient hormones. For instance, lack of thyroid-stimulating hormone results in fatigue, constipation or memory difficulties, and insufficiency of adrenocorticotropic hormone (ACTH) leads to weight loss, abdominal pain or low blood pressure. Despite the variety of signs and symptoms, there are few common ones, that are present in most of the cases.
The most common symptoms include:
- Weight loss
- Vision disorders
Diagnosis and treatment
The diagnosis is usually based on present symptoms and on blood tests. However, some hormones levels need to be measured with 2 different blood test approaches. First of them is a basal level test, which is done in the morning without stimulation. Second approach is a dynamic test, which is done after hormones stimulating. Other possible methods include urinalysis and imaging. The doctor can also ask about previous radiation therapies, head injuries and vision disorders.
In most cases of hypopituitarism, treatment course is lifelong and total or partial remission is rarely seen. It includes hormones replacement therapy, which is done in order to restore proper hormone levels, rather than fixing malfunctions standing behind those abnormalities. Hormone replacement medication can consist corticosteroids, growth hormone, sex-related hormones (testosterone and estrogen) or levothyroxine. Less common methods include surgery or radiation therapy.