Differential Diagnosis for Vulvar Pruritus in a 3-Year-Old Girl
- Single Most Likely Diagnosis
- Labial adhesions: The presence of an adhesive ridge fusing the posterior labia minora in the midline, along with vulvar pruritus and excoriation, suggests labial adhesions as the most likely diagnosis. This condition is common in prepubertal girls and can cause discomfort and itching due to the fusion of the labia.
- Other Likely Diagnoses
- Eczema or atopic dermatitis: Although there's no mention of atopy or skin lesions elsewhere on the body, eczema can sometimes be localized and could cause vulvar pruritus.
- Lichen sclerosus: This condition can cause pruritus and skin changes, but the absence of labial or vulvar atrophy and plaque formation makes it less likely.
- Pinworms (Enterobius vermicularis): Pinworm infection is common in children and can cause perianal and vulvar pruritus, especially at night.
- Do Not Miss Diagnoses
- Sexual abuse: Although there's no specific indication of abuse in the provided history, it's crucial to consider this possibility in any case of genital symptoms in a child. A thorough evaluation and possibly a referral to a specialist in child abuse pediatrics may be necessary.
- Urinary tract infection or other urinary tract abnormalities: Despite the normal urinalysis, it's essential to ensure there are no underlying urinary issues that could be causing the symptoms.
- Rare Diagnoses
- Psoriasis or other autoimmune skin conditions: These conditions are less common in young children but could potentially cause vulvar pruritus.
- Contact dermatitis: An allergic reaction to a substance coming into contact with the vulvar area could cause pruritus, although the history does not suggest recent changes in products that might cause this.
- Neurogenic causes: Rarely, vulvar pruritus could be a symptom of a neurological condition, but this would be unusual in a child without other neurological symptoms.