lactotroph hyperplasia
Increased prolactin-secreting cell mass in the pituitary, often physiologic during pregnancy or pathologic in certain conditions.
Full Definition
Lactotroph hyperplasia refers to the expansion of prolactin-producing cells (lactotrophs) in the anterior pituitary gland, which can occur through both physiological and pathological mechanisms. Physiological lactotroph hyperplasia occurs during pregnancy and lactation in response to estrogen stimulation, with the pituitary gland enlarging up to 50% during pregnancy. Pathological hyperplasia may develop secondary to hypothalamic dysfunction, dopamine receptor antagonist medications, primary hypothyroidism, or chronic kidney disease. Unlike prolactinomas, lactotroph hyperplasia typically involves diffuse cellular proliferation rather than discrete tumor formation. The condition can cause symptomatic hyperprolactinemia with galactorrhea, amenorrhea, and infertility, but usually responds well to dopamine agonist therapy or treatment of underlying causes.
Usage
Usage note: Distinguish from prolactinoma; hyperplasia implies diffuse cellular increase rather than discrete tumor formation.
In Context
- "Pituitary MRI showed diffuse enlargement consistent with lactotroph hyperplasia rather than a discrete adenoma." — Endocrinology consultation note
- "Post-partum lactotroph hyperplasia gradually resolved over six months with normalization of prolactin levels." — Obstetric endocrinology follow-up