In: Biology
What is a pheochromocytoma? What are the symptoms of this disorder? What is the pathophysiological basis for these symptoms?
Pheochromocytoma is a neuroendocrine tumor of the medulla of adrenal glands or extra adrenal chromaffin tissue that failed to involute after birth.That secretes a high amount of catecholamines ,mostly norepinephrine with some epinephrine as well.
Pheochromocytoma also known as paragangliomas (extra adrenal) - which is tumor originates in ganglia of the sympathetic nervous system.
symptoms -
sympathetic nervous system hyperactivity including skin sensation, flank pain , elevated heart rate , elevated blood pressure - orthostatic hypertension ( a fall in systolic blood pressure greater than 20 mmHg or a fall in diastolic blood pressure greater than 10 mmHg upon standing).
palpitations , anxiety , panic attack, pallor , weight loss , excessive sweating (diaphoresis) , headache.
localized amyloid deposition , elevated blood glucose level .
(symptoms are in bold are most common)
pathophysiology -
Mutations in the gene VHL , RET ,NF1 ,SDHB .SDHD are well known to cause pheochromocytoma.
The disease is mainly a tumor of the multiple endocrine neoplasia syndrome - type IIA(MEN IIA) and type IIB(MEN IIB). Pheochromocytoma linked to MEN II can be acused by RET oncogene mutations.