Evaluation of the male with possible hypogonadism

T: testosterone; LH: luteinizing hormone; FSH: follicle-stimulating hormone; PRL: prolactin; T4: thyroxine; Fe: iron; MRI: magnetic resonance imaging.

* This algorithm applies to the evaluation of outpatients. Males with acute or subacute illness should not be assessed for hypogonadism, as they will have a transient functional secondary hypogonadism.

¶ Iron and transferrin are measured to assess the possibility that hemochromatosis is the cause of secondary hypogonadism. When an MRI should be performed depends upon several factors. One is the patient's serum T relative to his age. A male <40 years with a serum T <250 ng/dL (8.7 nmol/L) warrants an MRI, but in a male >60 years, a value of <150 ng/dL (5.2 nmol/L) would be necessary to warrant it. An MRI should also be performed if other pituitary hormones are abnormal, eg, if serum prolactin is elevated or if serum T4 and/or early morning cortisol are below normal.