What are the causes of itching and erythema of the glans penis?

Causes of Itching and Redness of the Glans Penis

The most common cause of itching and redness of the glans penis is candidal balanitis, which should be treated with topical antifungal agents such as clotrimazole 1% cream or miconazole 2% cream applied 1-3 times daily for 7-14 days. 1

Primary Infectious Causes

Candidal Balanitis (Most Common)

• Candida albicans is the most frequent mycotic infection of the penis, with increasing incidence primarily transmitted through sexual intercourse. 2
• The accumulation of yeasts and other microorganisms under the foreskin contributes to inflammation, particularly in uncircumcised males. 3
• Clinical presentation includes itching, tenderness, erythema, and pain of the glans. 3
• Alternative topical options include terconazole 0.4% cream for 7 days or tioconazole 6.5% ointment as a single application. 1
• For more widespread or recurrent infections, oral fluconazole 150 mg as a single dose should be considered. 1
• Sexual partners should be treated if recurrent infections occur, as male partners may develop balanitis with erythematous areas on the glans with pruritus. 1

Bacterial Infections

• For patients under 35 years with suspected bacterial infection, give ceftriaxone 250 mg IM once PLUS doxycycline 100 mg orally twice daily for 10 days. 1
• For patients 35 years or older, give ofloxacin 300 mg orally twice daily for 10 days OR levofloxacin 500 mg orally once daily for 10 days. 1
• Obtain cultures before starting antibiotics, including Gram stain of any discharge and NAAT testing for N. gonorrhoeae and C. trachomatis. 1
• Mandatory reassessment at 3 days is required; if no improvement, consider abscess requiring surgical drainage or atypical organisms. 1

Sexually Transmitted Infections

• Herpes simplex virus infection is the commonest infectious cause of genital ulceration, with evidence that many infections are asymptomatic. 4
• HPV infection may present as condyloma acuminatum, most commonly caused by low-risk HPV 6 and 11. 4
• Scabies and pediculosis are transmitted by skin-to-skin contact with sexual transmission being common, with the penis and scrotum being favorite locations. 4

Inflammatory Dermatologic Causes

Lichen Sclerosus

• Lichen sclerosus presents as atrophic white patches on the glans penis and foreskin, though early disease can manifest as mild erythema before characteristic porcelain-white changes develop. 5, 6
• Common sites include the glans penis, coronal sulcus, frenulum, and prepuce, but itch is not a prominent symptom. 5
• The condition causes constrictive posthitis leading to paraphimosis, phimosis, and painful erections. 5
• Perimeatal involvement may lead to progressive meatal stenosis and urethral strictures. 5
• A biopsy must be considered if there is suspicion of neoplastic change, persistent hyperkeratosis, erosion or erythema, or if disease fails to respond to adequate treatment. 5
• First-line treatment is potent topical corticosteroids (clobetasol propionate 0.05% ointment applied once daily). 6
• Long-term follow-up is required due to risk of squamous cell carcinoma progression. 7

Psoriasis and Lichen Planus

• Common skin diseases like psoriasis and lichen planus may have an atypical appearance in the genital area. 4
• The typical psoriatic scale is usually not apparent because of moisture and maceration. 4, 8
• These conditions frequently involve the penis as part of generalized cutaneous disease. 8

Contact and Irritant Dermatitis

• Allergic contact dermatitis may result from condoms, lubricants, feminine hygiene deodorant spray, and spermicides. 4
• More often, contact dermatitis is irritant, resulting from persistent moisture and maceration. 4
• Excessive hygiene may cause "over-treatment balanitis." 8

Plasma Cell Balanitis

• This presents as a solitary, smooth, shiny, red-orange plaque of the glans and prepuce in middle-aged to older men. 4
• Squamous cell carcinoma in situ cannot be excluded clinically, and biopsy is required to confirm diagnosis. 4

Critical Red Flags Requiring Urgent Evaluation

• Suspect penile fracture if there is penile ecchymosis, swelling, a cracking/snapping sound during intercourse, and immediate detumescence, which requires urgent surgical exploration. 1
• Suspect Fournier gangrene if there is fever, severe pain, crepitus, or rapidly progressive necrosis, which requires immediate surgical debridement and broad-spectrum antibiotics. 5, 1
• Assess for ischemic priapism if the penis is completely rigid and painful, which is a medical emergency requiring intracavernous treatment. 1
• Evaluate for urethral injury if blood is present at the urethral meatus, gross hematuria, or inability to void. 1

Age-Specific Considerations

Older Men

• Any persistent penile lesion in older patients requires a biopsy to exclude neoplastic changes, particularly erythroplasia of Queyrat (penile intraepithelial neoplasia). 7
• Erythroplasia of Queyrat presents as a persistent erythematous plaque and is associated with HPV, with potential progression to invasive squamous cell carcinoma. 7
• Do not provide empirical treatment without biopsy for persistent penile erythema in older men to avoid delayed diagnosis of potentially malignant conditions. 7

Children

• In boys, lichen sclerosus typically presents with phimosis, and early disease can manifest as mild erythema before characteristic white changes develop. 6
• Do not mistake ecchymosis from lichen sclerosus as evidence of sexual abuse. 6
• Perianal involvement is extremely rare in male children, which helps distinguish this from other conditions. 6

Common Pitfalls to Avoid

• Do not delay surgical consultation if you suspect penile fracture, Fournier gangrene, or abscess formation, which require urgent intervention. 1
• Do not use over-the-counter antifungal preparations without confirming the diagnosis if symptoms persist beyond 2 months or worsen during treatment. 1
• Do not forget to evaluate and treat sexual partners for sexually transmitted causes to prevent reinfection. 1
• Abstain from sexual activity until treatment is completed and symptoms resolve. 1
• Do not overlook persistent erythema that fails to respond to standard treatment within 1-2 weeks, as this warrants further evaluation including possible biopsy. 7, 6