1. A 63-year-old man complains of a mildly painful and tender rash on his penis that has been there for almost two years. The patient is uncircumcised; when the foreskin is retracted, a bright red, erythematous, nonscaly, circumferential plaque is visible on the glans penis, spreading to the foreskin. He denies pain on urination, discharge, fever, malaise, arthralgias, and sexual contact outside of his marriage.
Diagnosis: Zoon balanitis is a benign condition that typically affects uncircumcised middle-aged to elderly men.1,2 Worldwide prevalence among uncircumcised men is approximately 3%.2 The etiology is unknown; it’s thought that this condition may be caused by friction, trauma, heat, lack of hygiene, exogenous or infectious agents, an IgE hypersensitivity, or a chronic infection with Mycobacterium smegmatis.1,2
Typically, the appearance of the lesion precedes diagnosis by about one to 2 years.1 The patient usually complains of mild pruritus and tenderness. Undergarments may be bloodstained.
The lesion associated with Zoon balanitis is a solitary, glistening, shiny, red-to-orange plaque of the glans penis or prepuce of an uncircumcised male. Pinpoint erythematous spots or “cayenne pepper spots” may also be associated with this condition.
For more information on this case, see “Erythematous penile lesion.” J Fam Pract. 2012;61(12):753-755.