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USMLE Step 2 (Subject) / Renal/Genitourinary (Lesson)
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- Indications for urethrogram - Blood at the meatus - Hematuria - Dysurea - Urinary retention
- Scleroderma renal crisis Occurs in 10–15% of cases of diffuse SSc Clinical features:- Oliguric renal failure- (Malignant) hypertension- Encephalopathy- Microangiopathic hemolytic anemia
- Rapidly progressive glomerulonephritis Etiology:Type I: Goodpasture syndromeType II: immune complex glomerulonephritis- IgA nephropathy, membranoproliferative nephropathy, Henoch-Schönlein purpura (HSP)- Lupus nephritis- Poststreptococcal glomerulonephritis (PSGN)Type III: glomerulonephritis associated with vasculitis (pauci-immune GN, ANCA associated)- Granulomatosis with polyangiitis (Wegener granulomatosis)- Microscopic polyangiitis- Eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome, EGPA) Clinical features:- Nephritic syndrome- Decrease in urine output within days to weeks → possibly anuria- Fatigue- Pulmonary symptoms (e.g., hemoptysis) may occur Treatment:- Glucocorticoids and cyclophosphamide- In the event of Goodpasture syndrome: plasmapheresis in addition to immunosuppression - RPGN due to ANCA-associated vasculitis (granulomatosis with polyangiitis, microscopic polyangiitis): combination therapy with glucocorticoids and rituximab is an effective alternative
- Urinary incontinence - Diagnostics Basic diagnostic testing- Detailed medical history (including medication)- Voiding diary to assess frequency and volume of micturition- Neurological, vaginal, and rectal examination - Urine dipsticks and urine culture to exclude urinary tract infections→ Indicated in patients with a complicated UTI and/or prolonged UTI (> 7 days)- Creatinine and blood urea nitrogen (BUN) - Sonography: Quantification of residual urine after micturition, renal ultrasound- Quantification of leaked urine: pad test Additional diagnostic testing- Micturating cysto-urethrogram (MCU) to detect morphological abnormalities- Urodynamic examination to measure bladder pressure and urethral closure pressure
- Further causes of urinary incontinence - Commonly seen in multiple sclerosis or spinal cord injury - Detrusor sphincter dyssynergia → simultaneous contractions of the detrusor muscle and involuntary activation of the internal urethral sphincter → blockage of bladder outlet → small amounts of urine are pressed through the contracted sphincter muscle → high intravesical pressure along with inappropriate contraction of the urethral sphincter Key features:- Voiding and/or storage dysfunction, intermittent voiding, urinary retention- Irregular, small volume incontinence without an associated urge to void (sometimes referred to as reflex incontinence) Treatment:- Injection of botulinum toxin into the detrusor muscle - Transurethral resection of external urinary sphincter (TURS)- Alpha-blockers and/or anticholinergics
- Hypospadias Common congenital malformation with incorrect positioning of the urethral meatus due to failure of urethral folds and foreskin to fuse on ventral penis. Etiology:- Genetic (e.g., disorders of sex development)- Endocrine (e.g., 5-alpha reductase deficiency) Epidemiology: Incidence is 1/250 male births Clinical features:- Ventrally displaced urethral meatus- Dorsal hooded foreskin- ± Underdeveloped penis & glans- ± Penile curvature (chordee)- Proximal hypospadias are associated with bifid scrotum and penoscrotal transposition- Associated with inguinal hernias and cryptorchidism Diagnostics: Clinical Management:- Defer circumcision- Urologic evaluation for surgical repair- ± Karyotype, pelvic ultrasound (if severe) Treatment:- Mild cases do not necessarily require surgery- Significant displacement or symptomatic micturition warrants surgical repair→ Reconstruction of urethra, penis, and scrotum at 6 months of age: urethroplasty and orthoplasty Complications following repair:- Urethral fistula- Meatal stenosis- Urethral diverticulum- UTI
- Calcific uremic arteriolopathy (calciphylaxis) Pathophysiology:- Arteriolar & soft tissue calcification- Local tissue ischemia & necrosis Risk factors:- End-stage renal disease- Hypercalcemia, hyperphosphatemia- Hyperparathyroidism- Obesity, diabetes- Oral anticoagulants (e.g., warfarin) Clinical features:- Painful nodules & ulcers- Soft tissue calcification on imaging- Skin biopsy: arterial calcification/occlusion, subintimal fibrosis
- Common causes of erectile dysfunction Vascular:- Cardiovascular risk factors (e.g., hypertension, smoking, diabetes)- Abnormal vascular examination (e.g., bruits, decreased pulses) Neurologic:- Neurologic comorbidity (e.g., diabetic neuropathy, multiple sclerosis, spinal injury/surgery)- Gradual onset, loss of bulbocavernosus reflex Psychogenic:- Sudden onset- Situational (e.g., ED with partner, normal erection during masturbation)- Normal nonsexual nocturnal erections Endocrine:- Additional symptoms due to underlying disorder- Abnormal hormone levels (e.g., TSH, prolactin) Medications:- Onset related to starting medication- Antihypertensives, SSRIs, anti-androgenic medications Hypogonadism:- Gradual onset- Decreased libido, gynecomastia, testicular atrophy- Low serum testosterone
- Paraphimosis Retracted foreskin in an uncircumcised male that cannot be returned to its original position Etiology:- Complication of phimosis (physiological or pathological)- Iatrogenic (i.e., following genitourinary procedures such as bladder catheterization)- Trauma (vigorous sexual intercourse, forceful retraction of foreskin while urinating, piercing) Clinical features:- Noticeable band of constricting tissue (at the coronal sulcus)- Foreskin cannot be returned to its original position- Edema and pain of the glans penis- Features of penile ischemia (blue penile skin and firm glans penis) Diagnostics: clinical diagnosis Treatment:- Conservative: manual reduction with adequate pain control (topical anaesthesia, local infiltration, or regional blocks) - Surgical: Dorsal slit reduction surgery (incision of the constricting band) if manual reduction fails or penile ischemia occurs- Circumcision is the last resort
- Phimosis Tight foreskin that cannot be completely retracted over the glans penis Epidemiology: Physiologic phimosis occurs in up to 10% of males at 3 years of age, but is less prevalent by 16 years of age (occurring in 1-5% of males). Etiology:- Post-infectious complication following balanoposthitis- Congenital- Scarring after trauma or circumcision Clinical features:- Difficulty in retracting the foreskin (relative phimosis)- Inability to retract the foreskin (full phimosis)- Painful erection and/or dyspareunia Diagnostics: clinical diagnosis Treatment:- Conservative: topical corticosteroid cream (contraindicated in recurrent infection) and stretching exercises- Surgical: vertical incision (incision of the constricting bands) or circumcision if conservative management fails Complications:- Foreskin tear with possible hemorrhage- Paraphimosis
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- Balanitis and balanoposthitis Balanitis: inflammation of the glans penis (may occur in both circumcised and uncircumcised males)Balanoposthitis: inflammation of both the glans penis and the foreskin Etiology:- Poor genital hygiene- Contact allergies and topical irritants- Drug reaction- Bacterial infection (e.g., especially sexually transmitted infections such as gonorrhea)- Yeast infection- Trauma Clinical features:- Pruritus, pain, and edema of the glans penis- Erythema and ulcerated lesions of the glans or foreskin- Thick penile discharge or discharge from ulcerated lesions- Systemic symptoms may occur (i.e., fever, arthralgias, malaise). Diagnostics: Usually a clinical diagnosis Treatment:- Daily retraction of the foreskin and bathing with warm saline solution- Avoid known irritants (e.g., soap, perfumes)- Treat underlying chronic condition- Surgical: circumcision in recurrent cases or clinically significant phimosis Complications:- Postinflammatory phimosis- Urinary tract obstruction → requires bladder catheterization- Recurrent urinary tract infections- Penile cancer