Zoon's balanitis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Vishal Devarkonda, M.B.B.S[2]

Synonyms and keywords:Balanoposthite chronique circonscrite bénigne á plasmocytes, Balanitis chronica circumscripta plasmacellularis, ZB, Zoon's vulvitis, Plasma cell vulvitis, Vulvitis circumscripta plasmacellularis

Overview

Zoon's balanitis is a rare nonveneral idiopathic, chronic, benign inflammatory mucositis of genitalia. It was first described in the modern literature by Zoon, in 1952. The exact pathogenesis is not clearly known. It present as well circumscribed single or multiple, orange-red in colour with a characteristic glazed appearance and multiple pinpoint redder spots-"cayenne pepper spots" most commonly involving the glans penis.

Historical Perspective

• In 1952, for the first time in medical literature, Zoon recognized a distinct entity in patients with chronic balanitis, named it as balanoposthite chronique circonscrite bénigne á plasmocytes” or “balanitis chronica circumscripta plasmacellularis.
• In 1954, Garnier reported the similar lesion in vulva.
• In 1956, Nikolowski described the identical lesion in oral mucosa.
• In 1963, Kortnig described the idential lesion in conjuntiva.

Classification

There is no established classification system for Zoon balanitis.

Pathophysiology

Pathogenesis

The exact pathogenesis is not clearly known, but following theories have been postulated:

• Accumlation of epithelial debris and secretions between foreskin and penis proximal to coronal sulcus, smegma, poor genital hygiene, repeated local infections, hot and humid weather results in chronic physical irritation or subclinical trauma, which in turn results in skin lesion along the lines of the trauma.
• Chronic infection with Mycobacterium smegmatis and human papillomaviruses (HPV) was found to be associated with development of Zoon balanitis.
• Many theories, which include 1) local disturbance of circulation, 2) hypersensitivity response mediated by IgE class of antibodies, 3) “extramedullary plasmacytic infiltrations that persists are expressions of occult multiple myeloma” have been postulated, no supportive evidence have been found for these hypothesis.

Histopathology

ZB has distinctive histopathological features, which include:

Epidermal

• Epidermal changes include, early thickening, acanthosis and parakeratosis of epidermis, which is followed by atrophy, erosions and spongiosis.
• Scattered neutrophils can be present in superficial erosions of the epidermis.
• Spongiosis accentuation occurs in the lower half of the spinous zone.
• Subepidermal clefts, necrotic keratinocytes, and lozenge keratinocytes can be seen in the late stages of ZB.

Dermal

• Dermal changes include patchy lichenoid infiltrate of lymphocytes and plasma cells in papillary dermis, which are replaced by plasma cells, neutrophils, eosinophils, lymphocytes, and erythrocytes.
• Dermal vascular dilatation with singular vertical or oblique orientation of proliferated individual vessels, is a characteristic feature of ZB.
• In the later stages, upper dermis shows fibrosis which correlates well with subepidermal clefts, epidermal atrophy, and plasma cell infiltrates.

Epidemiology and Demographics

Epidemiological and Demographic data of Zoon balanitis is scare.

Screening

There is no established screening guidelines for Zoon balanitis

Natural History, Complications, and Prognosis

Natural history

If left untreated, there is risk for malignant transformation.

Complications

Complications of Zoon balanitis include:

• Phimosis
• Paraphimosis

Prognosis

Prognosis is good with treatment.

Diagnosis

Diagnosis is made on by obtaining detailed history, physical examination and reflectance confocal microscopy/dermoscopy findings:

History and symptoms

Patients with Zoon balanitits could be asymptomatic or present with:

• Itching (pruritus) of the genitalia.
• Discomfort in urination(dysuria)
• Pain in the gential region
• blood stain discharge
• Difficult or painful sexual intercourse

Physical examination

Physical examination findings include:

• Well circumscribed single or multiple, orange-red in colour with a characteristic glazed appearance and multiple pinpoint redder spots-"cayenne pepper spots"(please click here to view the image) most commonly involving the glans penis, but inner surface of prepuce and coronal sulcus may be involved.
• Though uncommon, lesions of Zoon balanitis can involve other sites which include labia minora in females, oral mucosa, conjunctiva, urethra, cheeks, and epiglottis have been described in literature.

Clinical criteria in diagnosing Zoon balanitis
Shiny, erythematous patches on the glans, prepuce, or both
Lesion present for > 3months
Absence of lesion suggestive of Lichen planus, psoriasis elsewhere on the body
Poor response to topical therapies
Absence of concurrent infections which are ruled out after performing tzanck, potassium hydroxide, gram stain, and VDRL test.

Laboratory findings

Reflectance confocal microscopy	A nucleated honeycomb pattern and vermicular vessels is a clue for benign inflammatory genital skin disease
Dermoscopy	Focal/diffuse orange-yellowish structure, less areas representing hemosiderin deposition, curved vessels due to epidermal thinning helps in distinguishing ZB from carcinoma in situ.
Biopsy	Epidermis: Epidermis thickening which is followed by epidermal atrophy, at times with erosions.Dermis: Plasma cell infiltrate with haemosiderin and extravasated red blood cells.

Treatment

General measures

Good hygiene which include retracting the foreskin regularly and gentle cleansing of entire glans, preputial sac, and foreskin were found effective in treating the diseases.

Medical Therapy

Various medical managements for Zoon's balanitis
	Drug dosage	Effectiveness
Topical steroids	Saline compresses containing 1% hydrocortisone/0.02% betamethason+/-17-valerate/0.05% betamethasone dipropionate	3 out of 6 patients responded
	Oxytetracycline 3%, nystatin 100,00(units/g), and clobetasone butyrate 0.05% applied until complete resolution was observed	All patients responded, but 3 out of 10 patients had recurrences
Topical calineurin	Tacrolimus ointment 0.1% twice daily	Complete remission after 4 weeks of treatment was observed in 9 patients , with no relapse observed after 3 months of follow up
Topical Pimecrolimus	Pimecrolimus cream 1% twice daily	Improvement is observed after 2 months of treatment with no relapse observed
Topical Imiquimod	5% imiquimod cream, 3 times a week for 4 months with multiple periods without treatment	Complete resolution can be found after 4-12 weeks of treatment, with no cases of relapse observed
	5% imiquimod cream, 3 times a week for 12 months without any interruption

Surgery

Various surgical modalities for Zoon's balanitis
Circumcision	Lesion disappear by 5-6 weeks after procedure, with no relapse observed
Carbon dioxide lesion	Complete resolution in 3 months, with no relapse observed in following 5 years of follow up
Yag laser	Complete clearance is seen patients within 2-3 weeks, with no relapse observed in following 30 months of follow up
PDT	Lesion healed completely after an average 2.75 PDT sessions, with no relapse observed in following 1 year of follow up

Photodynamic therapy

Photodynamic therapy, 5-aminolaevulinic acid (ALA) or methyl aminolevulinate (MAL), has been proposed for refractory lesions of ZB. ALA-PDT seems to be slightly better than MAL-PDT, with no long-term side effects observed.

Miscellaneous therapies

Once-daily application fusidic acid cream for 8-16 weeks was effective in suppression and cure of ZB.

Prevention

Primary Prevention

Circumcision in males can help in reducing risk of having ZB.

Secondary prevention

There is no secondary prevention measures.