To recall the possible causes of penile sores, think of the smallest micro-organism up to the largest.
· Virus. This brings to mind genital herpes (herpes simplex virus 2 [HSV2]). Genital warts are included here, but are rarely difficult to diagnose.
· Bacteria. This should facilitate the recall of chancroid (caused by Haemophilus ducreyi; bacillus), lymphogranuloma venereum and granuloma inguinale (caused by calymmatobacterium granulomatous). Abscess and balanitis should also be recalled here.
· Spirochete. This suggests chancre, the first stage of syphilis.
The above classification would not help recall an epithelioma or laceration and other lesions caused by trauma.
Approach to the Diagnosis
Something that is often neglected today is the tracking down of contacts which can assist in the diagnosis. A painless lesion suggests chancre, whereas a painful lesion is typical of chancroid, herpes simplex, or balanitis. The presence of inguinal lymphadenopathy should alert the clinician to lymphogranuloma venereum, chancre, and epithelioma.
A smear and culture should be done if balanitis or chancroid is the clinical diagnosis. A dark field examination is done to confirm the diagnosis of chancre. The finding of intracellular Donovan bodies will confirm the diagnosis of granuloma inguinale. A Tzanck test will assist in the diagnosis of genital herpes but is not usually necessary. Serologic tests or a Giemsa stain of scrapings of the primary lesion may be examined for inclusion bodies in cases of lymphogranuloma venereum. A biopsy is necessary to diagnose an epithelioma.