Orchitis

Epididymitis is inflammation of the epididymis, most often infectious, causing unilateral scrotal pain and swelling of gradual onset that must be distinguished urgently from testicular torsion. Diagnosis is clinical, supported by a positive Prehn sign and preserved cremasteric reflex, and treatment is empiric ceftriaxone plus doxycycline for age under 35 or STI risk, or levofloxacin alone for age over 35 with enteric-organism risk.

Testicular torsion is twisting of the spermatic cord causing testicular ischemia, presenting with acute severe unilateral scrotal pain, a swollen high-riding testis in a horizontal lie, and an absent cremasteric reflex; it is a surgical emergency diagnosed clinically without delaying for imaging, and testicular viability falls from 90-100% within 6 hours of symptom onset to under 10% beyond 24 hours, so immediate surgical exploration with detorsion and bilateral orchiopexy is the definitive treatment.

Mumps is a paramyxovirus infection that has re-emerged with declining vaccination rates and classically causes parotitis with fever, headache, and malaise, complicated by orchitis, aseptic meningitis, pancreatitis, or hearing loss. Diagnosis is confirmed by PCR or IgM serology and management is supportive, since prevention through the two-dose MMR vaccine is the only proven control measure.

Hydrocele is a painless accumulation of serous fluid within the tunica vaginalis, congenital and communicating in infants or acquired and noncommunicating in adults, diagnosed by transillumination and confirmed with scrotal ultrasound; treatment is observation for asymptomatic disease and hydrocelectomy for persistent or symptomatic cases.

Varicocele is dilation of the pampiniform venous plexus and internal spermatic veins, usually left-sided because of the right-angle insertion of the left gonadal vein into the left renal vein, presenting as a painless, non-transilluminating 'bag of worms' scrotal mass that augments with standing or Valsalva and is a leading cause of male infertility. Diagnosis is clinical, confirmed by scrotal Doppler ultrasound when uncertain, and management is conservative (scrotal support, NSAIDs) for asymptomatic cases without testicular atrophy, escalating to surgical ligation or percutaneous embolization for pain, testicular atrophy, or infertility in a patient desiring fertility.

Klinefelter syndrome is a 47,XXY sex chromosome disorder and the most common cause of primary male hypogonadism, occurring in about 1 in 600 live births. Adult men present with tall stature, small firm testes, gynecomastia, and infertility from azoospermia; the diagnosis is confirmed by karyotype showing 47,XXY, and treatment is lifelong testosterone replacement, which does not restore fertility.

Infectious urethritis is inflammation of the urethra from a sexually transmitted pathogen, most often Neisseria gonorrhoeae, Chlamydia trachomatis, or Mycoplasma genitalium, presenting with dysuria and urethral discharge. Diagnosis rests on urethral or urine leukocytes plus nucleic acid amplification testing, and empiric treatment covers gonorrhea with ceftriaxone and chlamydia with doxycycline while results are pending.

Testicular cancer is the most common solid tumor in men aged 15 to 35 and is usually cured even when metastatic, because germ cell tumors are exquisitely chemosensitive. A painless testicular mass is worked up with scrotal ultrasound and serum tumor markers, radical inguinal orchiectomy establishes the diagnosis and provides local control, and post-orchiectomy markers plus CT staging then guide surveillance, radiation, retroperitoneal lymph node dissection, or cisplatin-based chemotherapy.