What is the differential diagnosis for prepuce wounds?

Differential Diagnosis of Prepuce Wounds

The differential diagnosis for prepuce wounds must systematically distinguish between traumatic, infectious, inflammatory, and neoplastic etiologies, with infectious causes (particularly Candida and bacterial balanoposthitis) being most common, followed by lichen sclerosus as the primary chronic inflammatory condition requiring biopsy confirmation.

Infectious Etiologies

Bacterial and Fungal Balanoposthitis

• Candida albicans is the most frequently isolated organism in infectious balanoposthitis, accounting for a significant proportion of cases in uncircumcised males 1
• Staphylococcus species and groups B and D Streptococci are the most common bacterial pathogens isolated from prepucial infections 1
• Clinical presentation includes erythema, edema, purulent discharge, and erosions, though the clinical appearance alone has little predictive value for identifying the specific infectious agent 1
• Honey-colored crusting suggests impetigo caused by Staphylococcus aureus or Streptococcus pyogenes 2
• Bacterial rashes typically show purulent exudate, pustules, and rapid progression with surrounding erythema, while fungal infections characteristically demonstrate peripheral scaling and satellite lesions without purulent drainage 2

Viral Infections

• Herpes simplex virus (HSV) must be considered in the differential, presenting with vesicular and/or ulcerative lesions on the genitals 3
• Laboratory confirmation should always be sought as clinical differentiation from other causes of genital ulceration is difficult 3
• Treponema pallidum (syphilis) can occasionally be recovered from the same lesion as HSV 3

Inflammatory and Dermatologic Conditions

Lichen Sclerosus (LS)

• LS is the primary chronic inflammatory condition affecting the prepuce and represents the only absolute indication for circumcision 4
• In males, LS typically affects the prepuce, coronal sulcus, and glans penis, presenting as porcelain-white plaques with areas of ecchymosis 3
• The incidence of LS in children with phimosis ranges from 14% to 100% depending on the study 3
• Biopsy is mandatory if there is suspicion of neoplastic change, failure to respond to adequate treatment, or atypical features 3
• Classic histological features include thinned epidermis with hyperkeratosis, homogenized collagen band below the dermoepidermal junction, and underlying lymphocytic infiltrate 3

Other Inflammatory Conditions

• Fixed drug eruption may present with genital ulceration and can be confused with infectious etiologies 3
• Behçet syndrome can cause mucosal ulcerations in the genital region 3
• Inflammatory bowel disease (Crohn disease) may manifest with genital lesions 3

Traumatic Etiologies

Accidental Trauma

• Zipper injuries are the most common accidental prepuce injury in children 5
• Straddle injuries can crush the penile urethra between the pubic bones and a fixed object 6
• Blunt trauma may cause contusions, lacerations, or hematomas of the prepuce 5

Coital and Self-Inflicted Injuries

• Coital injuries account for the majority (85%) of adult prepuce trauma cases 5
• Predisposing phimosis or short frenulum is commonly present in patients with coital injuries 5
• Self-inflicted injuries represent a significant proportion of adult cases 5

Iatrogenic Causes

• Urethral catheterization is a common iatrogenic cause of urethral and prepucial bleeding, particularly with traumatic or improper placement 6
• Transurethral surgery is the most common etiology of iatrogenic strictures in men 6

Neoplastic Conditions

Squamous Cell Carcinoma (SCC)

• SCC risk in patients with genital LS is less than 5%, but approximately 60% of vulval SCCs occur on a background of LS 3
• Suspicious features requiring biopsy include persistent hyperkeratosis, erosion, erythema, or new warty/papular lesions 3
• Verrucous carcinoma is a less common malignancy associated with LS 3
• Biopsy is mandatory for any non-healing lesions or pigmented areas to exclude abnormal melanocytic proliferation 3

Critical Diagnostic Approach

Initial Assessment

• When blood is present at the urethral meatus in trauma cases, retrograde urethrography must be performed first before any catheterization attempt, as blind catheterization may worsen the injury 6
• Clinical findings suggesting urethral injury include blood at meatus, inability to urinate, perineal/genital ecchymosis, and high-riding prostate on examination 7

Laboratory Confirmation

• Biopsy or aspiration should be implemented as an early diagnostic step when infection versus other etiologies cannot be distinguished clinically 3
• Material collection from vesicles or ulcers should be obtained for viral culture, nucleic acid amplification testing, or immunofluorescence staining 3
• Culture studies confirm infectious etiology in approximately 64% of clinically suspected infectious balanoposthitis cases 1

Key Diagnostic Pitfalls

• The clinical aspect of balanoposthitis has little value in predicting the specific infectious agent, necessitating laboratory confirmation 1
• Exclusive reliance on clinical diagnosis leads to both false positive and false negative diagnoses of genital HSV infection 3
• In immunocompromised patients, the differential diagnosis is wider and includes bacterial, viral, fungal, and parasitic agents that are not typically considered 3
• Ecchymosis in prepucial lesions of children may be mistaken for sexual abuse, though LS exhibits the Koebner phenomenon and can be caused or aggravated by trauma 3