The Urinary Tract and the Reproductive System E-book Flashcards
Testosterone produced during
Testosterone produced during foetal development then for the first few months.
The testes then remain dormant until puberty.
GnRH) are released from
Pulses of gonadotrophin releasing hormone (GnRH) are released from the hypothalamus which stimulates follicle stimulating hormone (FSH) and luteinizing hormone (LH) release from the pituitary
LH stimulates the
LH stimulates the testes to secrete androgens, primarily testosterone from the Leydig cells.
FSH stimulates the
FSH stimulates the Sertoli cells in the seminiferous tubules in the testes to secrete androgen-binding protein (ABP).
When does Testosterone stimulate spermatogenesis.
Only in the presence of ABP
Sertoli cells release
Sertoli cells release inhibin, a protein hormone that inhibits FSH secretion by the anterior pituitary. If spermatogenesis is proceeding too slowly, less inhibin is released, which permits more FSH secretion and an increased rate of spermatogenesis.
Testosterone inhibits
Testosterone inhibits GnRH secretion by the hypothalamus and decreases the sensitivity of the pituitary to GnRH. This negative feedback mechanism
decreases during puberty.
Testosterone stimulates
Testosterone stimulates the development of secondary sex characteristics
Dihydrotestosterone (DHT) stimulates
Dihydrotestosterone (DHT) stimulates the development of pubic, axillary and facial hair
Testosterone causes.. to enlarge
Testosterone causes ducts and glands of reproductive system to enlarge
Testosterone stimulates a
Testosterone stimulates a growth spurt leading to increased muscle mass, increased basal metabolic rate and a larger larynx
why males have a higher haematocrit and RBC than females.
Testosterone stimulates erythropoiesis which is
What leads to increased libido
Testosterone stimulates the brain leading to increased libido
As a man ages,
As a man ages, testosterone levels drop from a peak of approximately 7mg/day at 20 years of age to 1/5 of this aged 80. Feedback inhibition of the pituitary decreases and levels of FSH and LH increase.
Prostate gland
Located immediately below the bladder and immediately in front of the rectum.
Consists of between 30 and 50 tubulacinar glands in fibrous capsule.
These produce a thin, milky secretion which empties through approximately 20 poresin the urethral wall.
Secretion makes up approximately 30% of semen.
Position in front of the rectum means that it can be palpated through the rectal wall - digital rectal examination (DRE).
Benign Prostate Enlargement (BPE) / Benign Prostatic Hyperplasia (BPH)
BPE/BPH is the most common disorder of the prostate responsible for LUTS. It is a condition that is common in older men.
Pathophysiology: BPE
BPE/BPH occurs when there is hyperplasia of the epithelial and stromal components of the prostate gland, which leads to progressive obstruction of urine flow and increased activity of the detrusor muscle (Berry et al (1984) cited by Wilt and N’Dow 2008).
Pathogenesis thought to be androgen/oestrogen imbalance.
DHT thought to be the main stimulator of the growth of prostatic glands.
Symptoms: BPE
Frequency of urination is a common early symptom.
Difficulty or delay in initiating urination with variability and reduced forcefulness of urinary stream and post-void dribbling often present.
Acute urinary retention or retention with overflow incontinence may occur.
Digital rectal examination (DRE) – smooth enlarged prostate = benign hyperplasia.
BPE/BPH – Differential diagnoses:
/BPH – Differential diagnoses: Poorly controlled diabetes Neurological disorders UTIs Chronic bacterial prostatitis Overactive bladder Medication: diuretics, anticholinergics,antidepressants Lifestyle factors: caffeine, alcohol, excess intake of liquids
not routinely required for diagnosis as BPE/BPH is not a risk factor for prostate cancer
Prostate specific antigen (PSA) and DRE
BPE/BPH – management
Observation (watchful waiting) if only growing slowly
Lifestyle management
Modification of existing medication and/or management of co-existing medical conditions
Prostate and bladder specific drug treatment
Surgical treatments
BPE lifestyle
Reassurance
Reduce fluid or diuretic intake
Avoid excess or night-time fluid intake
Avoid caffeine
Avoid alcohol
Void bladder before long trips, meetings or bed time
BPE Co-morbidities
Review control ofdiabetes
Review any diuretic therapies
BPE drug therapy
- α-blockers
- 5α-reductase
- Antimuscarinics
Other adjunct drug treatments include:
Diuretics, desmopressin
α-blockers
Improve bladder and prostate smooth muscle tone.
Review patient 4 – 6 weeks after starting therapy then annually thereafter.
5α-reductase inhibitors
Can be used alone or in combination with an α-blocker dependent on symptoms, results and prostate size
Reduce prostate size.
Sexual function side effects.
Improvement in symptoms generally seen within 3 - 6 months of starting treatment
Review patient 3 - 6 months after starting therapy then every 6 - 12 months thereafter
Antimuscarinics
Decrease hypercontractility of detrusor muscle.
Useful for symptoms of overactive bladder.
BPE Surgical options
The standard surgical option is transurethral resection of prostate (TURP):
“This involves endoscopic removal of the inner (paraurethral) zones of the enlarged prostate using a diathermy loop.” (Wilt TJ, N’Dow J, 2008)
This is a highly effective procedure and is the gold standard. The associated risks are those of the general anaesthetic itself and severe haemorrhage
- Transurethral incision of the prostate (TUIP), Laser prostatectomy.
Surgical options risks
impotence
incontinence
need for further treatment due to stricture formation, urinary retention or disease relapse
Erection mechanism
draw
ED Possible causes:
Ageing Cardiovascular disease Neurological disease Diabetes mellitus Medication i.e. drug induced prescription or non prescription Fear of failure Hormonal Depression
ED Co-morbidities
ED may be the first symptom of diabetes mellitus in approximately 20% of cases of ED
Risk factors for ED are very similar to those for cardiovascular disease
ED itself is a risk factor for cardiovascular disease
(equivalentto moderate smoking)
Risk factors:
Sedentary lifestyle
Obesity
Smoking
Hypercholesterolaemia
Metabolic syndrome
ED in an otherwise asymptomatic man could be a marker for underlying cardiovascular disease.
Hyperthyroidism may cause ED as there is increased SHBG production leading to
o decreased free testosterone levels. Successful treatment of hyperthyroidism may resolve co-existing ED.
Thiazides and non-selective beta-blockers may cause ED.
Treatment of ED 1st and 2nd line
Identification and treatment of reversible lifestyle factors.
Identification and treatment of reversible hormone imbalances.
Review of drug therapies for co-existing diseases.
Psychosexual/relationship therapy
First-line treatment: -Phosphodiesterase type-5 inhibitors sildenafil (Viagra) tadalafil (Cialis) vardenafil (Levitra) avanafil (Spedra) -Vacuum erection devices
Second-line treatments: - Intracavernous injection therapy alprostadil (Caverject, Viridal Duo) - Intraurethral alprostadil medicated pellet (MUSE) - Topical (tip of penis) Alprostadil (Vitaros)
Unlicensed ED treatments
Papaverine, phentolamine
Third-line treatments: Penileprosthesis
Prostatitis - acute or chronic
BPE/BPH and prostate cancer are relatively common pathologies of the prostate, but a rarer condition of the prostate is prostatitis, which is an inflammation of the prostate. The main symptoms are: pelvic pain pain on urination pain on ejaculation.
A man who presents with these symptoms should be referred immediately to his GP. If prostatitis has been caused by a bacterial infection then it needs urgent treatment with antibiotics; early treatment will prevent damage to the prostate gland and halt the spread of infection to the surrounding urinary tract
The Cycle - Female
Each month after puberty until menopause, gonadotrophins, follicle stimulating hormone (FSH) and luteinising hormone (LH) are secreted by the anterior pituitary.
Each oocyte is surrounded by a single layer of follicular cells – called primordial follicles.
FSH and LH stimulate the development of several primordial follicles which start to grow into primary follicles. One of these follicles develops further to a secondary follicle and eventually matures to a mature (graafian) follicle. Just before ovulation, the diploid primary oocyte undergoes first phase meiosis. This produces two haploid cells, each with 23 chromosomes but unequal in size. The smaller cell produced by meiosis is called the first polar body and contains discarded nuclear material. The larger cell, known as the secondary oocyte, receives most of the cytoplasm. Once a secondary oocyte is formed it begins meiosis II but then stops in metaphase. The mature graafian follicle then ruptures releasing the secondary oocyte – ovulation. Meiosis II only continues if sperm is present in the fallopian tubes and fertilisation occurs. Otherwise all cells degenerate.
The process of ovulation
In the adult female, higher brain centres impose a menstrual cycle of 28 days upon the activity of hypothalamic GnRH
Pulses of GnRH, at about 2-hour intervals, stimulate the release of pituitary LH and FSH
LH stimulates ovarian androgen production by ovarian theca cells
FSH stimulates follicular development and aromatase activity (an enzyme required to convert ovarian androgens to oestrogens) in the ovarian granulosa cells. FSH also stimulates release of inhibin from ovarian stromal cells, which inhibits FSH release. Activin counteracts inhibin
Secretion and physiological effects of oestrogens, progesterone, relaxin, and inhibin in the female reproductive cycle
Oestrogens show a double feedback action on the pituitary, initially inhibiting gonadotrophin secretion (negative feedback), but later high-level exposure results in increased GnRH secretion and increased LH sensitivity to GnRH (positive feedback) which leads to the mid-cycle LH surge including ovulation from the leading follicle
High levels of oestrogens exert a positive feedback effect
The follicle then differentiates into a corpus luteum, which secretes both progesterone and oestradiol during the second half of the cycle (luteal phase).
Oestrogen initially and then progesterone, cause uterine endometrial proliferation in preparation for possible implantation; if implantation does not occur, the corpus luteum regresses and progesterone secretion and inhibin levels fall so that the endometrium is shed (menstruation) allowing increased GnRH and FSH secretion
If implantation and pregnancy follow, human chorionic gonadotrophin (hCG) production from the trophoblast maintains corpus luteum function until 10-12 weeks of gestation, by which time the placenta will be making sufficient oestrogen and progesterone to support itself
Menorrhagia
Normal menstrual flow is around 35-80ml; menorrhagia can be defined as a menstrual flow of 80ml or more. NICE guidance CG44 defines it as “as excessive menstrual blood loss which interferes with the woman’s physical, emotional, social and material quality of life, and which can occur alone or in combination with other symptoms. Any interventions should aim to improve quality of life measures.” For the majority of women, there is no obvious cause for heavy periods, but it may also be a symptom of an underlying disease. Conditions such as polyps, endometriosis, fibroids, pelvic inflammatory disease or polycystic ovary disease can also resultin heavy periods.
Copper intrauterine devices (IUDs) are associated with heavy menstrual flow. Certain endocrine disorders such as hypothyroidism may also disrupt the menstrual cycle and result in heavy menstrual periods.
Dysmenorrhoea
Dysmenorrhoea describes painful periods associated with low abdominal cramping pain which may also spread to the back and thighs.
Primary dysmenorrhoea: no underlying pelvic disease. Pain is caused by increased endometrial production of prostaglandins that facilitate smooth muscle contraction in the uterus.
Secondary dysmenorrhoea is caused by some underlying pelvic disease such as endometriosis, fibroids, pelvic inflammatory disease or adenomyosis. Dysmenorrhoea is also associated with IUD, especially in the first few months after insertion. Secondary dysmenorrhoea is more common in women aged between 30 and 45. Any woman of this age group presenting with dysmenorrhoea for the first time, or with severe or worsening pain, should be encouraged to further investigate their symptoms.
Amenorrhoea
This is defined as an absence of periods or markedly irregular infrequent periods (oligomenorrhoea). Polycystic ovary syndrome (PCOS) is the most common cause.
Weight-related amenorrhoea – a minimum body weight is necessary for regular menstruation and may be seen at weights within “normal” range. Restoration of body weight to above 50th centile for height is usually effective in restoring menstruation but oestrogen replacement is often necessary.
Hypothalamic amenorrhoea – low oestrogen and gonadotrophin levels in the absence of organic pituitary disease, weight loss or excessive exercise. It may be related to stress, weight loss or stopping the contraceptive pill, but some patients can have defective cycling mechanisms without explanation.
Hypothyroidism- oligomenorrhoea and amenorrhoea are common in severe hypothyroidism in young women.
Polycystic Ovary Syndrome (PCOS)
PCOS is characterised by multiple small cysts in the ovaries (which represent follicles under arrested development), excess androgen production from the ovaries (and to a lesser extent the adrenal glands). Levels of androgens vary from patient to patient.
SHBG levels are often low due to high insulin levels leading to high free androgen levels.
Hair follicle response to circulatory androgens is very variable, even with identical clinical and biochemical features therefore it is very difficult to predict symptomology