Pickardt syndrome denotes a rare form of tertiary

hypothyroidism Hypothyroidism is an endocrine disease in which the thyroid gland does not produce enough thyroid hormones. It can cause a number of symptoms, such as cold intolerance, poor ability to tolerate cold, fatigue, extreme fatigue, muscle aches, co ...

that is caused by interruption of the portal veins connecting

hypothalamus The hypothalamus (: hypothalami; ) is a small part of the vertebrate brain that contains a number of nucleus (neuroanatomy), nuclei with a variety of functions. One of the most important functions is to link the nervous system to the endocrin ...

and

pituitary The pituitary gland or hypophysis is an endocrine gland in vertebrates. In humans, the pituitary gland is located at the base of the brain, protruding off the bottom of the hypothalamus. The pituitary gland and the hypothalamus control much of th ...

.It was characterized in 1972 and 1973 by Renate Pickardt and Rudolf Fahlbusch.

Signs and symptoms

Cause

Interruption of the portal system may be caused by

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

s compressing the infundibulum. Other causes for Pickardt's syndrome are

inflammatory disorders Inflammation (from ) is part of the biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. The five cardinal signs are heat, pain, redness, swelling, and loss of function (Latin ''calor'', ''d ...

and

traumatic brain injury A traumatic brain injury (TBI), also known as an intracranial injury, is an injury to the brain caused by an external force. TBI can be classified based on severity ranging from mild traumatic brain injury (mTBI/concussion) to severe traumati ...

. An inborn variant of Pickardt's syndrome that is associated with certain mutations (

HESX1 Homeobox expressed in ES cells 1, also known as homeobox protein ANF, is a homeobox protein that in humans is encoded by the ''HESX1'' gene. Expression of HEX1 and HESX1 marks the anterior visceral endoderm of the embryo. The AVE is an extra-em ...

LHX4 LIM/homeobox protein Lhx4 is a protein that in humans is encoded by the ''LHX4'' gene. This gene encodes a member of a large protein family which contains the LIM domain, a unique cysteine-rich zinc-binding domain. The encoded protein may functio ...

) is referred to as ''pituitary stalk interruption syndrome (PSIS)''.

Endocrine consequences

Typical manifestations of Pickardt–Fahlbusch syndrome are hypothyroidism with reduced TSH values and functional

hyperprolactinemia Hyperprolactinaemia (also spelled hyperprolactinemia) is a condition characterized by abnormally high levels of prolactin in the blood. In women, normal prolactin levels average to about 13 ng/mL, while in men, they average 5 ng/mL. ...

(which is caused by disinhibition of

prolactin Prolactin (PRL), also known as lactotropin and mammotropin, 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 secr ...

release). Other

endocrine The endocrine system is a messenger system in an organism comprising feedback loops of hormones that are released by internal glands directly into the circulatory system and that target and regulate distant organs. In vertebrates, the hypotha ...

disorders that are usually associated with Pickardt syndrome are suprasellar failures like secondary

hypogonadism Hypogonadism means diminished functional activity of the human gonad, gonads—the testicles or the ovary, ovaries—that may result in diminished biosynthesis, production of sex hormones. Low androgen (e.g., testosterone) levels are referred t ...

, reduced levels of

growth hormone Growth hormone (GH) or somatotropin, also known as human growth hormone (hGH or HGH) in its human form, is a peptide hormone that stimulates growth, cell reproduction, and cell regeneration in humans and other animals. It is thus important in ...

and, in more severe cases, secondary

adrenal insufficiency Adrenal insufficiency is a condition in which the adrenal glands do not produce adequate amounts of steroid hormones. The adrenal glands—also referred to as the adrenal cortex—normally secrete glucocorticoids (primarily cortisol), mineraloco ...

Diagnosis

Pickardt's syndrome may cause difficulties in differential diagnosis of

pituitary adenoma Pituitary adenomas are tumors that occur in the pituitary gland. Most pituitary tumors are benign, approximately 35% are invasive and just 0.1% to 0.2% are carcinomas.prolactinoma A prolactinoma is a tumor (adenoma) of the pituitary gland that produces the hormone prolactin. It is the most common type of functioning pituitary tumor. Symptoms of prolactinoma are due to abnormally high levels of prolactin in the blood ( hyp ...

s may be associated with increased prolactin levels, central hypogonadism and central hypothyroidism. Usually, the prolactin levels are higher in case of a true prolactinoma, but the concentration ranges overlap.

Treatment

Treatment modality depends on the cause. Tumors may be removed surgically, but pituitary stalk interruption may persist. Usually, replacement of those

hormone A hormone (from the Ancient Greek, Greek participle , "setting in motion") is a class of cell signaling, signaling molecules in multicellular organisms that are sent to distant organs or tissues by complex biological processes to regulate physio ...

s that are reduced due to failed

feedback control Feedback occurs when outputs of a system are routed back as inputs as part of a chain of cause and effect that forms a circuit or loop. The system can then be said to ''feed back'' into itself. The notion of cause-and-effect has to be handled ...

systems will be necessary.

References

External links

{{Transcription factor/coregulator deficiencies Endocrine diseases Diseases named after discoverers