Penile Ulceration/ Sores
Differential Diagnosis
Common Diagnoses
- Herpes Simplex Virus (HSV)
- Boil/Infected Sebaceous Cyst
- Balanitis: Bacterial or Fungal
- Trauma: Zipper Injury Commonest; Also Torn Frenulum, Bites, Self-Mutilation
- Balanitis Xerotica Obliterans (BXO)
Occasional Diagnoses
- Herpes Zoster
- Reiter’s Syndrome: Circinate Balanitis
- Allergic Contact Eczema
- Chancroid (Soft Sore: Haemophilus Ducreyi)
- Granuloma Inguinale (Klebsiella Granulomatis: Tropical Infection)
- Lymphogranuloma Venereum (Tropical Infection)
Rare Diagnoses
- Syphilis (Chancre)
- Carcinoma of the Penis
- Tuberculosis
- Dermatological Conditions (e.g. behçet’s Syndrome, Lichen Planus)
- Fixed Drug Eruption
Ready Reckoner
Key distinguishing features of the most common diagnoses
| Herpes Simplex | Boil | Balanitis | Trauma | BXO | |
|---|---|---|---|---|---|
| Dysuria | Possible | No | Possible | Possible | Possible |
| Contact with Symptoms | Possible | No | Possible | No | No |
| Inguinal Nodes Enlarged | Yes | Possible | Possible | No | No |
| Discrete Single Lesion | No | Yes | No | Possible | No |
| Generally Unwell | Possible | No | No | No | No |
Possible Investigations
Likely:Swab, syphilis serology.
Possible:Urinalysis, FBC, ESR/CRP.
Small Print:Patch testing, biopsy.
- Urinalysis: In balanitis, may detect undiagnosed diabetes.
- Swab: May reveal infectious cause, e.g. herpes simplex, Candida, chancroid, lymphogranuloma venereum and granuloma inguinale (if STD suspected, then other appropriate swabs and blood tests for coexistent disease will be performed at GUM clinic).
- FBC and ESR/CRP: Raised WCC and ESR/CRP in significant infection or inflammation (e.g. Reiter’s syndrome).
- Syphilis serology: If syphilis suspected (Note: May take up to 3 months to become positive after initial infection).
- Patch testing: If allergic contact eczema a possibility.
- Biopsy (in secondary care): To confirm suspected malignancy or reveal underlying skin condition (e.g. lichen planus).
Top Tips
- Take a full sexual history, even in the older patient. If STD is suspected, refer to a GUM clinic for investigation, counselling and contact tracing.
- A diagnosis of HSV may induce a number of worries in the patient, some of them well founded, others less so. Give the patient plenty of time to talk through the diagnosis and its implications properly.
- Whatever the cause, the patient is very likely to fear an STD. Ensure that inappropriate anxieties are resolved.
- Enquire after coexistent or previous dermatological problems in obscure cases – this may provide the diagnosis (e.g. lichen planus).
Red Flags
- A history of travel or sexual contact with travellers is important – a number of the more obscure causes are ‘tropical’.
- Take a sexual history – syphilis is rare generally but is more common in homosexuals.
- Balanitis and urethritis, arthritis and conjunctivitis form the triad of Reiter’s syndrome. Always make a thorough general systemic enquiry.
- A single, unexplained, persistent ulcer needs thorough investigation as significant disease (infection or malignancy) is likely.
- Remember the possibility of underlying diabetes in severe or recurrent candidal balanitis.