What is the appropriate evaluation and management for a patient presenting with scrotal edema, a groin rash, and scattered skin lesions?

Evaluation and Management of Scrotal Edema with Groin and Body Rash

Immediate ultrasound with Doppler is mandatory to exclude life-threatening testicular torsion and Fournier gangrene, followed by targeted treatment based on the most likely infectious or inflammatory etiology. 1, 2

Immediate Life-Threatening Conditions to Exclude

Testicular Torsion

• Perform duplex Doppler ultrasound immediately if there is acute onset of scrotal pain with edema, as testicular viability is compromised if surgical exploration is not performed within 6-8 hours of symptom onset 1, 2
• Look for decreased or absent testicular blood flow on color Doppler, the "whirlpool sign" of twisted spermatic cord, and high position of the testicle with abnormal cremasteric reflex 1, 3
• Immediate urological consultation for surgical exploration is required if torsion is suspected, as delay beyond 6-8 hours significantly increases risk of testicular loss 1, 2

Fournier Gangrene

• Suspect Fournier gangrene if fever, severe pain, crepitus, or rapidly progressive necrosis are present—this requires immediate surgical debridement and broad-spectrum antibiotics 4, 5
• The infection begins insidiously with discrete perineal necrosis that progresses rapidly over 1-2 days with advancing skin necrosis, often extending to the scrotum, penis, perineum, and anterior abdominal wall 4
• Most cases are caused by mixed aerobic and anaerobic flora including staphylococci and Pseudomonas species 4
• Imaging should not delay surgical intervention in hemodynamically unstable patients or those with clinical signs of necrotizing infection 4

Diagnostic Workup

Laboratory Tests

• Obtain complete blood cell count; serum sodium, potassium, glucose, creatinine, and magnesium; urea; inflammatory markers (C-reactive protein, procalcitonin); coagulation assessment and lactate 4
• C-reactive protein level greater than 24 mg/L (228.6 nmol/L) suggests epididymitis/orchitis rather than torsion 3
• Obtain cultures including Gram stain of any discharge and nucleic acid amplification testing for N. gonorrhoeae and C. trachomatis if sexually transmitted infection is suspected 5

Imaging

• Duplex Doppler ultrasound of the scrotum is the first-line imaging modality with sensitivity of 96-100% for detecting testicular torsion and high sensitivity (90%) and specificity (93.3%) for necrotizing soft tissue infections 1, 4
• Grayscale examination should assess testicular homogeneity, scrotal wall thickening, and characteristics of any skin lesions 1
• Color and Power Doppler assessment evaluates testicular perfusion—increased epididymal flow with scrotal wall thickening and hydrocele suggests epididymo-orchitis 1, 2

Most Likely Diagnosis: Infectious Epididymo-Orchitis

Treatment for Sexually Active Men Under 35 Years

• Administer Ceftriaxone 250 mg IM single dose PLUS Doxycycline 100 mg PO twice daily for 10 days 1, 2
• This regimen covers N. gonorrhoeae and C. trachomatis, the most common pathogens in this age group 2, 5

Treatment for Men 35 Years or Older or Enteric Organisms

• Administer Ofloxacin 300 mg PO twice daily for 10 days OR Levofloxacin 500 mg PO once daily for 10 days 2, 5
• This regimen covers enteric organisms, which are more common in older men or those with urinary tract abnormalities 2

Adjunctive Therapy

• Prescribe bed rest, scrotal elevation, and analgesics until fever and local inflammation subside 2
• Advise abstaining from sexual activity until treatment is completed and symptoms resolve 5

Alternative Diagnoses to Consider

Lymphatic Filariasis

• Consider if the patient has traveled to endemic areas (equatorial Africa, West Pacific, Caribbean, South America, India, SE Asia) and presents with acute fever, localized skin inflammation with lymphadenitis, lymphangitis, chronic lymphedema, and scrotal edema/hydrocele 4
• Diagnosis requires serology and nocturnal blood microscopy (10 pm to 2 am in 4x citrated blood bottles, not refrigerated) 4
• Treatment requires specialist input: Diethylcarbamazine (DEC) PO 6 mg/kg in 3 divided doses for 14 days plus Doxycycline PO 200 mg daily for 6 weeks, after excluding onchocerciasis and loiasis 4

Crohn's Disease (Metastatic Crohn's Disease)

• Genital edema can occur as an extraintestinal manifestation of Crohn's disease, typically preceding gastrointestinal symptoms in 88% of pediatric cases 6
• Evaluation for Crohn's disease is necessary in all patients presenting with unexplained genital swelling, particularly if there are associated gastrointestinal symptoms or the patient is a child or adolescent 6
• Treatment of the underlying Crohn's disease with systemic medications (average 3.4 medications including topical and systemic agents) is most helpful 6

Candidal or Inflammatory Dermatoses

• If the groin and body rash is erythematous with pruritus, consider candidal infection and apply topical antifungal agents such as clotrimazole 1% cream or miconazole 2% cream 1-3 times daily for 7-14 days 5
• For more widespread or recurrent infections, consider oral fluconazole 150 mg as a single dose 5
• If the rash shows atrophic white patches, consider lichen sclerosus and perform a biopsy when there is suspicion of neoplastic change, persistent hyperkeratosis, erosion, or failure to respond to treatment 5

Extramammary Paget's Disease

• Suspect if there is a persistent eczematous lesion in the groin, scrotum, or penis that does not respond to topical ointments 7
• Early biopsy and histological examination is crucial for early surgical intervention, as delayed diagnosis can lead to locally advanced unresectable disease 7

Follow-Up and Monitoring

• Mandatory reassessment at 3 days is required—failure to improve necessitates reevaluation of both diagnosis and therapy 2, 5
• Persistent swelling and tenderness after completion of antimicrobial therapy should prompt comprehensive evaluation for tumor, abscess, infarction, testicular cancer, or tuberculous/fungal epididymitis 2
• If symptoms persist beyond 2 months or worsen during treatment, do not continue empiric therapy without confirming the diagnosis 5

Critical Pitfalls to Avoid

• Do not delay surgical consultation if you suspect testicular torsion, Fournier gangrene, or abscess formation, as these require urgent intervention 5, 4
• False-negative Doppler evaluations can occur in partial torsion or spontaneous detorsion, so maintain high clinical suspicion even with normal imaging 2
• Do not forget to evaluate and treat sexual partners for sexually transmitted causes to prevent reinfection 5
• Early presentation may not show all classic symptoms, potentially leading to missed diagnosis—maintain a low threshold for imaging and specialist consultation 2