Zoon Balanitis
Gonzalo De Toro, MD
Key Facts
Clinical Issues
Benign process with chronic course, with only a few cases that respond to corticosteroids
In men, most of the cases are cured by circumcision
Laser ablation can also be effective
Microscopic Pathology
Epithelium appears thinned and flattened
Sometimes may be partially detached or even absent
Mild spongiosis
Dense lymphocytic lichenoid infiltrate in the upper and mid submucosa, with abundant mature plasma cells
Epithelium with diamond- or lozenge-shaped, flattened keratinocytes
Top Differential Diagnoses
Primary and secondary syphilis
Cutaneous plasmacytosis
 Zoon balanitis presents as an erythematous plaque that is often well demarcated  . |
 Zoon balanitis histologically shows an atrophic epithelium with flattened diamond-shaped keratinocytes  and mild spongiosis. |
TERMINOLOGY
Synonyms
Plasmacytosis mucosae
Plasma cell balanitis
Balanitis circumscripta plasmacellularis (men)
Vulvitis circumscripta plasmacellularis (women)
Plasma cell cheilitis (lip)
Plasmocytosis circumorificialis (oral)
Idiopathic lymphoplasmacellular mucositis-dermatitis (skin and mucosal surfaces)
Definitions
Idiopathic lymphoplasmacellular mucositis-dermatitis is generic term for any inflammatory accumulation of plasma cells at mucosal or cutaneous sites
Zoon balanitis is reserved for localized involvement of prepuce or glans penis
ETIOLOGY/PATHOGENESIS
