Is a left adrenal gland that is mildly thickened something to be concerned about? ct report said it may represent hyperplasia. what can cause this?

Adrenal abnormality: Why was the ct done? It is common to discover something "incidentally" on the adrenals. Cts are very sensitive and they pick up all sorts of things that are often nothing more than "warts". See your doctor. With this info, you need to determine whether your adrenal(s) are producing too much hormone. Then you and your doctor need to figure out who used the term "hyperplasia" and why.