UT5 - Andrologia (3) Flashcards
Microbiologic Assessment?
❑ Abnormal urine samples
❑ Urinary and genital tract infections
❑ Prostatitis, epididymitis
❑ Male accessory gland infection (MAGI)
❑ Sexually transmitted diseases
❑ A small ejaculate volume may point to a (partial) obstruction of the ejaculatory ducts caused by (chronic) infection of the prostate or seminal vesicles
Imaging?
❑ Scrotal ultrasound/color Doppler ultrasound
* Testicles that are difficult to locate (ectopia, hydrocele or obesity)
* Testicular size
* Testicular lesions (tumors)
* Testicular microlithiasis (in infertile men might indicate testicular carcinoma in situ – CIS)
* Dilation of the rete testis
* Enlarged epididymis with cystic lesions (spermatocele)
* Characterize varicoceles
❑ Transrectal ultrasound of the prostate
* Low seminal volume and suspected distal obstruction (seminal vesicle dilation, midline prostatic cysts obstructing the ejaculatory ducts)
❑ Renal ultrasound
* Renal agenesia/ectopia (ipsilateral absence of the vas deferens)
Genetic Testing?
❑ Tem maior valor prognóstico do que diagnóstico
❑ Incidence of genetic abnormalities in infertile men – 5%
❑ The risk of karyotype abnormalities increases with the severity of spermatogenic impairment
❑ Indications for genetic testing:
* Sperm concentration is 10 million/mL,
* Clinical suspicion of an abnormality
* When In vitro fertilization (IVF) is used to treat male factor infertility due to the possible transmission of genetic disorders to offspring
❑ Most commonly used tests: karyotype, Y chromosome microdeletion analysis, and cystic fibrosis testing
Karyotype - Klinefelter syndrome (47, XXY)?
❑ The most frequent sex chromosome abnormality in men (prevalence of 1:600)
❑ The phenotype varies from normal virilization to stigmata of androgen deficiency (female hair distribution, scanty body hair, and long arms and legs – biótipo ectomórfico)
❑ All men have small firm testicles, and Leydig cell function is commonly impaired
❑ Testosterone – normal or low; Estradiol – normal or high; FSH – high
❑ Androgen replacement is often required with aging
❑ Spermatogenesis is frequently impaired and deteriorates further after puberty
❑ Most patients have azoospermia
❑ A MicroTESE* (feita se azoospérmico) em 30-50% dos casos permite obter espermatozoides.
❑ A Criopreservação (feita se oligoospérmico) deve ser realizada na puberdade, porque a oligospermia tende a agravar com a idade.
*MicroTESE: microsurgical testicular sperm extraction
Karyotype - Y chromosome microdeletions?
❑ Long arm of the human Y chromosome (Yq) hosts several genes involved in spermatogenesis
❑ Yq AZF microdeletions are associated with spermatogenic failure
❑ AZF microdeletions (AZFa, AZFb, and AZFc regions) are the most frequent molecular genetic cause of azoospermia and severe oligozoospermia
❑ Classical AZF deletions are never found in normospermic men 🡪 clear-cut cause-and-effect relationship with spermatogenic failure
❑ Screening is indicated in infertile men with a sperm count <5 million/ml
❑ Deletions are rare (0.7%) with a sperm count >5 million/ml
❑ Y deletions compatible with the presence of spermatozoa in the testis or ejaculate are obligatorily transmitted to the male offspring 🡪 genetic counselling
AZF: fator azoospérmico
Y chromosome microdeletions - Prevalence?
❑ Deletion of AZFc – 65–70%; tem fenótipo variável desde azoospermia até oligospermia severa com 70% de hipótese de obter espermatozoides na microTESE
❑ Deletions of the AZFb, AZFb+c or AZFa+b+c – 25–30%; associa-se a um arrest da espermatogénese com ausência de espermatozoides na microTESE
❑ Deletions of the AZFa – 5%; ausência de células germinativas; corresponde ao Sertoli cell-only syndrome, non-testicular cell in microTESE
Screening for cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations?
❑ O CFTR codifica para uma proteína / canal iónico crucial que manutenção da viscosidade através do equilíbrio Na+/Cl- nas secreções epiteliais. O CFTR influencia a formação de todas as estruturas do ducto ofiano, nomeadamente o ducto ejaculatório, a vesícula seminal, o ducto deferente e os 2/3 distais de epidídimo.
❑ Cystic fibrosis (CF) is an autossomal-recessive disorder
❑ CF is the most common genetic disease in Caucasians
❑ Men with CF are azoospermic due to congenital bilateral absence of the vas deferens (CBAVD)
❑ Isolated CBAVD is considered a mild form of CF
❑ >80% of patients with CBAVD carry mutations of the CFTR gene (7p)
❑ Men with CBAVD should undergo genetic screening
❑ Candidates for microsurgical (MESA) or percutaneous epididymal sperm aspiration (PESA) or testicular sperm extraction (TESE) with intracytoplasmatic sperm injection (ICSI) – técnicas de reprodução medicamente assistida
❑ A critical point in the evaluation of CBAVD is the workup of the female partner for CFTR mutations (carrier frequency in European descent is 1/25)
Testicular Dysfunction / Nonobstructive Azoospermia?
❑ Testicular dysfunction is the most frequent cause of disturbed spermatogenesis
❑ Severe forms of testicular failure are severe OAT syndrome and NOA (azoospermia não obstrutiva)
❑ Low testicular volume (<15 ml) and/or consistency
❑ Usually high FSH (hypogonadotropic hypogonadism)
❑ Low testosterone
Obstructive Azoospermia?
❑ OA is the absence of both spermatozoa and spermatogenetic cells in semen and post ejaculate urine due to the bilateral obstruction of the epididymis, the seminal vesicle or ejaculatory duct
❑ Normal testicular volume (>15 ml), enlarged epididymis, nodules in the epididymis or vas deferens, absence/atresia of the vas deferens, signs of urethritis or prostatitis, and prostatic abnormalities on rectal examination
❑ Normal FSH
❑ Congenital or acquired complete obstruction of the ejaculatory ducts or the seminal vesicles are commonly associated with low semen volume, decreased/absent seminal fructose, and acid pH
Varicocele?
❑ Varicocele is a common abnormality which may be associated with:
– failure of ipsilateral testicular growth
– symptoms of pain and discomfort
– male subfertility
– hypogonadism
❑ The exact association between reduced male fertility and varicocele is unknown, but a meta-analysis showed that semen improvement is usually observed after surgical correction.
❑ Contudo a melhoria da fertilidade pode não ocorrer ou não há evidência que a correção cirúrgica conduza a melhoria da fertilidade.
❑ Current evidence indicates that microsurgical varicocelectomy is the most effective with the lowest complication rate among the varicocelectomy techniques
Hypogonadism?
❑ Provide testosterone replacement therapy for symptomatic patients with primary and secondary hypogonadism who are not considering parenthood
❑ In men with hypogonadotropic hypogonadism, induce spermatogenesis by an effective drug therapy (human chorionic gonadotropin, human menopausal gonadotropin, recombinant follicle-stimulating hormone, highly purified FSH)
❑ Do not use testosterone replacement for the treatment of male infertility
Idiopathic Male Infertility?
❑ No demonstrable cause of infertility is found in at least 44% of infertile men
❑ Alguns estudos mostram que o uso de antioxidantes orais pode melhorar o espermograma
Male Contraception?
❑ Vasectomy meets best the criteria for mal contribution to permanent contraception, with regard to efficacy, safety and side effects
❑ All available data indicate that vasectomy is not associated with any serious, long-term side-effects
❑ Microsurgical vasectomy reversal is a low-risk and cost-effective method of restoring fertility
❑ Methods of male contraception other than vasectomy are associated with high failure rates or are still experimental
❑ A vaso-vasostomia (ou reversão microcirúrgica da vasectomia) deve ser considerada como método de reparação da vasectomia antes dos métodos de reprodução assistida.
