Hypophysitis refers to an

inflammation Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...

of the

pituitary gland In vertebrate anatomy, the pituitary gland, or hypophysis, is an endocrine gland, about the size of a chickpea and weighing, on average, in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain. The ...

. Hypophysitis is rare and not fully understood.

Signs and symptoms

There are four categories of symptoms and signs. Most commonly, the initial symptoms are headaches and visual disturbances. Some symptoms are derived from the lesser functioning of the adenohypophyseal hormones. Of the adenohypophyseal hormones, the most frequently affected are

corticotrope Corticotropes (or corticotrophs) are basophilic cells in the anterior pituitary that produce pro-opiomelanocortin (POMC) which undergoes cleavage to adrenocorticotropin (ACTH), β-lipotropin (β-LPH), and melanocyte-stimulating hormone (MSH). Thes ...

s, lactotropes and

gonadotrope Gonadotropic cells (called also Gonadotropes or Gonadotrophs or Delta Cells or Delta basophils) are endocrine cells in the anterior pituitary that produce the gonadotropins, such as the follicle-stimulating hormone (FSH) and luteinizing hormon ...

s, all which are found in the anterior pituitary.

Polyuria Polyuria () is excessive or an abnormally large production or passage of urine (greater than 2.5 L or 3 L over 24 hours in adults). Increased production and passage of urine may also be termed diuresis. Polyuria often appears in conjunction wit ...

is also a common symptom – which results in very dilute urine, as well as

polydipsia Polydipsia is excessive thirst or excess drinking.Porth, C. M. (1990). ''Pathophysiology: Concepts of altered health states''. Philadelphia: J.B. Lippincott Company. The word derives from the Greek () "very thirsty", which is derived from (, "mu ...

which means having extreme thirst. Another symptom is

hyperprolactinemia Hyperprolactinaemia is the presence of abnormally high levels of prolactin in the blood. Normal levels average to about 13 ng/mL in women, and 5 ng/mL in men, with an upper normal limit of serum prolactin levels being 15-25 ng/mL ...

, which is when there are abnormally high prolactin levels in the blood. Usually, a mass will be found located on the

sella turcica The sella turcica (Latin for 'Turkish saddle') is a saddle-shaped depression in the body of the sphenoid bone of the human skull and of the skulls of other hominids including chimpanzees, gorillas and orangutans. It serves as a cephalometric la ...

and loss of hormonal function.

Cause

Hypophysitis may have an underlying autoimmune aetiology, as in the case of

autoimmune hypophysitis Autoimmune hypophysitis is defined as inflammation of the pituitary gland due to autoimmunity. Signs and symptoms Autoimmune hypophysitis can lead to deficiencies in one or more pituitary hormones, causing central diabetes insipidus if the poster ...

, and lymphocytic hypophysitis.

Diagnosis

Mainly, the diagnosis of hypophysitis is through exclusion – patients often undergo surgery because they are suspected of having a pituitary adenoma. But, the most accurate diagnosis is using Magnetic Resonance Imaging (MRI) to find any mass or lesions on the sella turcica. It is a known side-effect of the new

immune checkpoint Immune checkpoints are regulators of the immune system. These pathways are crucial for self-tolerance, which prevents the immune system from attacking cells indiscriminately. However, some cancers can protect themselves from attack by stimula ...

inhibitors of the

CTLA-4 CTLA-4 or CTLA4 (cytotoxic T-lymphocyte-associated protein 4), also known as CD152 (cluster of differentiation 152), is a protein receptor that functions as an immune checkpoint and downregulates immune responses. CTLA-4 is constitutively expres ...

inhibitor and PD-L1 inhibitor classes, used for the treatment of

melanoma Melanoma, also redundantly known as malignant melanoma, is a type of skin cancer that develops from the pigment-producing cells known as melanocytes. Melanomas typically occur in the skin, but may rarely occur in the mouth, intestines, or eye ( ...

, and should be considered in patients on these drugs who present with

endocrine The endocrine system is a messenger system comprising feedback loops of the hormones released by internal glands of an organism directly into the circulatory system, regulating distant target organs. In vertebrates, the hypothalamus is the neu ...

dysfunction.

Treatment

It was shown through various testing that administration of

bromocriptine Bromocriptine, originally marketed as Parlodel and subsequently under many brand names, is an ergoline derivative and dopamine agonist that is used in the treatment of pituitary tumors, Parkinson's disease, hyperprolactinaemia, neuroleptic maligna ...

can improve field of vision defects and lower

prolactin Prolactin (PRL), also known as lactotropin, is a protein best known for its role in enabling mammals to produce milk. It is influential in over 300 separate processes in various vertebrates, including humans. Prolactin is secreted from the pit ...

levels. It was also found that when using

corticosteroids Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involve ...

, there was a decrease in size of the gland, and relieved compression on the dura mater. These corticosteroids were also found to have an immunosuppressive effect which helped with reducing the autoimmune reaction of the gland.

Prognosis

The prognosis for hypophysitis was variable for each individual. The depending factors for hypophysitis included the advancement of the mass on the sella turcica, percentage of fibrosis, and the body's response to corticosteroids. Through the use of corticosteroids, the vision defects tend to recover when the gland size began to decrease. The prognoses of the limited number of reported cases were usually good.

History

The first reported case was in 1962, with a 22-year-old who died of adrenal insufficiency 14 months after giving birth to her second child. Her symptoms began 3 months postpartum, with

lassitude Fatigue describes a state of tiredness that does not resolve with rest or sleep. In general usage, fatigue is synonymous with extreme tiredness or exhaustion that normally follows prolonged physical or mental activity. When it does not resolve ...

(weakness/lack of energy),

goitre A goitre, or goiter, is a swelling in the neck resulting from an enlarged thyroid gland. A goitre can be associated with a thyroid that is not functioning properly. Worldwide, over 90% of goitre cases are caused by iodine deficiency. The term is ...

(iodine deficiency) and

amenorrhea Amenorrhea is the absence of a menstrual period in a woman of reproductive age. Physiological states of amenorrhoea are seen, most commonly, during pregnancy and lactation (breastfeeding). Outside the reproductive years, there is absence of menses ...

(absence of a menstrual period). This was originally reported by Goudie and Pinkerton in Glasgow, UK. There have only been approximately just over 100 cases reported. Majority of these cases were female, and usually began noticing symptoms late into their pregnancies and in early postpartum.http://pathology2.jhu.edu/hypophysitis/histricalnotes.cfm

References

{{Pituitary disease Pituitary disorders Inflammations