A 32-year-old man comes to the office due to vision problems. Over the last 6 weeks, he has had several "near-misses" while driving, having been nearly hit by cars coming from both the right and left sides. He also reports frequent headaches. The patient has no prior medical conditions and takes no medications. He does not use tobacco, alcohol, or illicit drugs. Physical examination reveals deficits in the bilateral temporal visual fields. Extraocular movements are bilaterally intact, and the remainder of the neurological examination shows no abnormalities. Which of the following additional findings is most likely to be present in this patient?

Question

A 32-year-old man comes to the office due to vision problems.  Over the last 6 weeks, he has had several "near-misses" while driving, having been nearly hit by cars coming from both the right and left sides.  He also reports frequent headaches.  The patient has no prior medical conditions and takes no medications.  He does not use tobacco, alcohol, or illicit drugs.  Physical examination reveals deficits in the bilateral temporal visual fields.  Extraocular movements are bilaterally intact, and the remainder of the neurological examination shows no abnormalities.  Which of the following additional findings is most likely to be present in this patient?

Quizplus · Accepted Answer

11ec160b_3ac8_27d9_9249_ff4613673471_MD0001_00 This patient's symptoms are worrisome for a pituitary tumor. Large tumors can cause headaches due to mass effect, and compression of the optic chiasm by suprasellar extension of the tumor can cause bitemporal hemianopsia. These tumors can also cause loss of normal pituitary function by compression of surrounding cells. Pituitary adenomas typically arise from 1 of the 5 major cell types of the anterior pituitary; physiologic symptoms depend on the hormones produced by the tumor. The most common hormonally active (functional) adenomas are prolactin-secreting adenomas (prolactinomas). Prolactin is a peptide hormone whose primary action is maintenance of lactation in the postpartum period; prolactinomas classically cause galactorrhea in premenopausal women. Prolactin also suppresses GnRH production from the hypothalamus, which in women leads to amenorrhea and in men causes hypogonadism (eg, impotence, decreased libido, infertility). Because the symptoms of hyperprolactinemia in men and postmenopausal women are often mild and nonspecific, patients may not seek care until the tumors are large and cause mass effect symptoms. (Choices B, D, and F) Somatotroph (growth hormone-secreting) adenomas can present with gigantism (in children) or acromegaly in adults. Thyrotroph (TSH-secreting) adenomas cause central hyperthyroidism (eg, heat intolerance, tachycardia). Thinning of the skin, typically manifesting as abdominal stria, is a characteristic feature of Cushing syndrome; when hypercortisolism is due to a corticotroph (ACTH-producing) adenoma, it is referred to as Cushing disease. These tumors are significantly less common than prolactinomas. (Choice C) Mass lesions involving the pituitary stalk or posterior pituitary could cause headaches and bitemporal hemianopsia in addition to central diabetes insipidus (due to decreased release of antidiuretic hormone [ADH] from the posterior pituitary). However, polyuria is typically only transient (lasting <6 weeks) because the hypothalamus is able to bypass the pituitary and directly release ADH into the circulation. (Choice E) Hyperpigmentation in the context of pituitary disease is typically due to hypersecretion of ACTH, either due to a corticotroph adenoma or in response to primary adrenal insufficiency. Educational objective: Pituitary tumors can present with headaches, bitemporal hemianopsia, and hypopituitarism; the most common hormonally active (functional) adenomas are prolactin-secreting adenomas (prolactinomas). Prolactinomas can cause galactorrhea and amenorrhea in women. In men, they often present with hypogonadism. __________ References: Progress in the diagnosis and classification of pituitary adenomas. (http://www.ncbi.nlm.nih.gov/pubmed/26124750)

A 32-Year-Old Man Comes to the Office Due to Vision