Brief Answer:
Nodule will have to be analyzed first

Detailed Answer:
Hello XXXXXXX

Thanks for posting in behalf of your husband,

Well the nodule on left side could actually mean nothing and just a benign mass with no direct effect on your husband's health. If his parathyroid hormone is elevated it might probably be due to hypocalcemia or low serum magnesium or increased phosphorus etc which might be due to the direct cause from his renal failure. PTH level can increase in response to changes in blood electrolytes such as calcium, magnesium or phosphorus and the increase is only aimed at regulating those minerals. With the renal failure, it would actually be difficult for these electrolytes to be regulated given that he has end-stage renal failure.
A parathyroid gland growth (hyperplasia) or a parathyroid tumor can also cause this increase PTH. Your husband's nodule will need to be examined maybe a biopsy done to analyze the type of growth and what its clinical significance is. If this nodule is responsible for increase PTH, then the option will be to remove it surgically.
So saying, with your husband's medical history, I could suspect that his increase PTH is due to his renal diseases.
I think you should discuss this with his doctor as his treatment options will also depend on his other medical conditions.

Hope this helps and wish you both the best.
Dr. Nsah

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