Chronic pruritic vulva lesion
The patient was not sexually active and denied any vaginal discharge. So what was causing the intense itching on her labia?
Lichen sclerosus is a cutaneous disease of unknown origin that tends to occur in postmenopausal women; it prompts complaints of pruritus and dyspareunia.5 It presents as white atrophic plaques that may encompass both the vagina and rectum.4,5
Psoriasis lesions are usually distinctive, with red scaling papules that tend to coalesce into plaques. These lesions are associated with Auspitz sign—pinpoint bleeding following removal of silvery white scale.4,5 Lesions are often found on the elbows, groin, knees, scalp, gluteal cleft, fingernails, and toes.4
Mycosis fungoides (MF) is a cutaneous T-cell lymphoma that can have similar clinical characteristics to lichen simplex chronicus. It evolves through 4 phases: pre-MF, patch, plaque, and tumor.4 The patch phase may be confused with lichen simplex chronicus because there are flat, erythematous, and pruritic lesions. It also presents with lymphadenopathy and lesions that are persistently resistant to topical steroid treatments. High clinical suspicion and multiple biopsies at different sites may be useful.
Extramammary Paget’s disease is a rare cutaneous form of adenocarcinoma. About 12% of patients have a concurrent underlying internal malignancy.4,5 It appears as a white-to-red, scaling or macerated, infiltrated, eroded, or ulcerated plaque, most frequently observed on the labia majora and scrotum.5
2 keys to diagnosis
A history of severe pruritus (with a chronic itch-scratch cycle) combined with the findings of lichenification should make you suspect lichen simplex chronicus. It may be necessary to first treat the itch-scratch cycle before you can identify the underlying disease.1 If clinical diagnosis is still unclear, you may need to do a skin biopsy for pathologic identification and to rule out neoplasia.
Look for concomitant psychiatric disorders that often have contributing factors, such as depression, anxiety, and obsessive-compulsive disorder.1,4,5 Correlation of history, physical exam, and pathophysiology is enough for the diagnosis.
