Diagnostic work-up II
Similarly, other possible signs of hypogonadism include gynaecomastia as well as a decrease in beard and body hair growth. Assessment of the peripheral vascular system is also important to determine the characteristics of the pulse, to ascertain the presence of an arterial bruit (a vascular sound that is associated with turbulent blood flow).
The evaluation of the penis in the flaccid condition might show the presence of Peyronie disease (involving palpable fibrous plaques), phimosis (congenital narrowing of the opening of the foreskin) or frenulum breve (whereby the tissue under the
glans penis that connects to the foreskin is too short and restricts the movement of the foreskin), which can all contribute to erectile dysfunction. Measurement of blood pressure, waist circumference and body mass index is also performed105 .
A few biochemical and hormonal parameters are of value in patients with erectile dysfunction. However, levels of
cholesterol, triglycerides, fasting glucose and glycosylated haemoglobin (HbA1c) are important determinants of
cardiovascular and metabolic risk stratification105,106. Total testosterone and sex hormone-binding globulin for the
evaluation of calculated free testosterone105,106 are sufficient parameters to rule out hypogonadism. Prolactin and thyroid hormone evaluation are limited to a subset of patients105,106
The vast majority of men with erectile dysfunction are managed within the primary care setting. However, in the
presence of abnormal biochemical or hormonal values, further diagnostic tests are advisable (second-line evaluation). If the fasting plasma glucose level is 100–126 mg dl−1, or HbA1c is
>5.7%, an oral glucose tolerance test can be used to exclude overt type 1 and type 2 diabetes mellitus.
The necessity of performing further cardiovascular evaluation should be based on the criteria of the Princeton III Consensus Panel100 (TABLE 1). In the presence of reduced total
testosterone and/or calculated free testosterone, obtaining prolactin and gonadotropin levels will determine the source (central or peripheral) of the problem.
Recent data have documented that penile duplex Doppler ultrasound (PDDU) can be performed in both flaccid (before vasodilator stimulation) and dynamic states (after vasodilator stimulation) to further improve the stratification of cardiovascular risk in men with erectile dysfunction103,107,108. Nocturnal penile tumescence and rigidity testing using the RigiScan device (GOTOP Medical, St Paul, Minnesota, USA) is currently rarely carried out109; its use is limited to testing the presence of nocturnal spontaneous erectile activity for medico-legal purposes when the
presence of naturally occurring erections needs to be demonstrated. Arteriography and dynamic infusion cavernosometry (measuring cavernosal blood pressure) and cavernosography (to assess venous leak) are carried out only in young men who are potential candidates for vascular reconstructive surgery
