Page 279 - Medicine and Surgery

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Chapter 6: Genitourinary oncology 275

Performance anxiety occurs in men who, after one Investigations

or more episodes of erectile dysfunction, become so Simple hormonal tests for prolactin levels, thyroid func-
anxious that subsequent attempts at intercourse fail, tion tests, testosterone levels are sometimes useful. Di-
leading to escalation of the problem. abetes mellitus should be looked for by urine dipstick/
Distractionorlossoffocus,e.g.byworkissuesorother blood sugar levels.

tasks that need to be done, can cause loss of erection
during sexual intercourse. Management
Drugs: Oral treatments include Sildenafil (Viagra) is a type 5
Commonly used drugs can cause impotence such phosphodiesterase inhibitor, which allows cyclic GMP

as antihypertensives, in particular thiazide diuretics, to accumulate (nitric oxide induced vasodilatation is
anti-depressants and drugs used to treat peptic ulcer mediated by cyclic GMP which is catabolised by type
disease. Barbiturates, corticosteroids, phenothiazines 5phosphodiesterase), so increasing the ability to gen-
and spironolactone may reduce libido. erate and maintain an erection. It needs to be taken
Nicotine and alcohol. Recreational drugs such as co- 1 hour before sex, and its effects last for 4 hours. Its

caine and hallucinogenic drugs can cause impotence vasodilation effects can cause headache, dizziness, a
with long-term use. blue tinge to vision (reversible) and even syncope. It is
Endocrine: contraindicatedwithconcomitantnitrateuse(includ-
Testosterone not only acts to increase libido, but is ing sublingual and GTN patch) within 24 hours, as

neededforarigiderection,bymaintainingnitricoxide profound hypotension can result. There are now two
synthase levels in the penis. Oestrogen therapy (e.g. newer similar drugs – vardenafil and tadalfil, which
for prostate cancer) can also result in impotence. have a more rapid onset, but longer duration of ac-
Hyperprolactinaemia, hyperthyroidism and hypothy- tion, allowing more spontaneity.

roidism. Anti-depressants such as selective serotonin reuptake
Diabetes lowers intracavernosal levels of nitric ox- inhibitors may be useful, particularly for premature

ide synthase, and these patients also have increased ejaculation.
atherosclerosis which can impair blood supply. Auto- Penile self-injection with vasoactive drugs such as pa-
nomic neuropathy is also an important factor. paverine, or alprostadil suit some individuals. An im-
Central sexual impulses (e.g. caused by images or portant side-effect is priapism – a prolonged erection
sounds) pass to T11-L2, which then sends signals to the which may need surgical intervention to remove clot.
pelvicvessels,toincreasebloodsupplytothepenis.There Vacuum devices can be used to ‘suck’ blood into the
isalsoareflexarcatS2–S4whichmeansthatgenitalstim- penis and then a ring is applied at its base to main-
ulation increases vascular flow. Neurological disease at tain the erection. Ejaculation is not possible with these
any level can therefore interfere with sexual function. devices.
Surgical intervention involves the implantation of a

prosthesis into the corpus cavernosa.
Clinical features Psychological counselling is useful for those with a
Some features in the sexual history, medical history or psychological cause.
examinationmaypointtowardsacause.Completelossof
erections, including nocturnal erections, suggests a neu-
rological or vascular cause. Sudden loss of sexual func- Genitourinary oncology
tion without any previous history of problems, or major
genital surgery, suggests performance anxiety, stress or Kidney tumours
loss of interest in the sexual partner. Ability to generate
an erection, but then inability to sustain it may be due Benign tumours are commonly found incidentally at
to anxiety or to a problem with vascular supply, or nitric post-mortems or on imaging.
oxide synthase levels, e.g. in diabetes. It is important to Renal adenomas are derived from renal tubular ep-
take a drug history and enquire about possible features ithelium. Tumours less than 3 cm in diameter are ar-
of depression, smoking, alcohol or drug abuse. bitrarily termed benign adenomas, but histologically