A preventative measure that can be utilized is prophylactic radiotherapy when a bilateral adrenalectomy is being performed in order to prevent Nelsons syndrome from manifesting. Screening can also be done with the help of an MRI in order to visualize the pituitary for tumors. If tumors are not present then an MRI should be performed at intervals. Hyper-pigmentation and fasting ACTH levels within plasma above 154 pmol/L are predictive of Nelsons syndrome after an adrenalectomy. Risk factors include being younger in age and pregnancy. Mechanism
After a bilateral adrenalectomy is performed cortisol levels are no longer normal. This increases CRH production because it is not suppressed within the hypothalamus anymore. The increased CRH levels promote the growth of the tumor. Mutations with genes and with the glucocorticoid receptor can affect the tumor as well. Furthermore, differences between Nelson syndrome and Cushings disease have been studied. Particularly Nelsons syndrome differs from Cushings disease due to the following: secretions from the tumors, replacement of glucocorticoids, and injury to the hypothalamus due to radiation therapy utilized on the patient. The pathophysiology of Nelsons syndrome is not understood very well. Corticotrophinomas are generated from corticotroph cells. Expression of functional CRH and vasopressin V3 receptors increase in number. Additionally, there are two isoforms of glucocorticoid receptors. Heterozygosity loss in the glucocorticoid receptor can occur in the tumors present from Nelsons syndrome. Overall, not all patients that have had a total bilateral adrenalectomy develop Nelsons syndrome, which makes the mechanism harder to understand for such a rare disease.
Folliculitis nares perforans is characterized by small pustules near the tip of the inside of the nose, lesions that become crusted, and when the crust is removed it is found that the bulbous end of the affected vibrissa is embedded in the inspissated material. : 774

See also
Skin lesion


== References ==