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A Sample Case: Admitted to the hospital complaining of chest pain, a 50 year old man also complained of problems with vision which were getting progressively worse. He described drinking copious amounts of water each day for many years. This was accompanied by polyuria and nocturia. Upon questioning he revealed that he had not ever had a significant sex drive.

His general physical examination was consistent with an acute myocardial infarct. He weighed 250 pounds and was 5 feet 6 inches tall. Apart from cardiac abnormalities he was in generally good health.

He was alert, well oriented with good memory, and appropriate well articulated speech. Cranial nerve examination was normal except for vision which showed a bitemporal hemianopsia. Motor and sensory examination were normal. During his hospital stay his temperature fluctuated between 37.30 and 37.90 C daily.

Explanation -

There was no indication of problems with higher cortical functions. Sensory and motor signs were absent as were cranial nerve signs except for the optic nerves. The bitemporal hemianopsia indicates involvement with the optic chiasm.

Long-standing excessive intake of water suggests diabetes insipidus which may be due to lesions of the hypothalamus or the posterior pituitary for the synthesis and release of antidiuretic hormone (ADH). Additionally, he had poor temperature control, was of short stature, overweight, and with self-described low libido. These phenomena are functions controlled by the hypothalamus. In the midline of the hypothalamus is the ventromedial nucleus which controls food intake, and the supraoptic/paraventricular nuclei which synthesize ADH; the hypothalamus is known to regulate body temperature and secrete gonadotrophin releasing-hormone, which may be responsible for the absence of libido. The long standing, slowly progressive nature of these problems suggest that the etiology is not of vascular origin but more likely is due to a slow growing tumor.