General Practice and Population Healthcommon
A 29-year-old woman presents with painful genital lesions that began as small blisters 3 days ago. She describes burning on urination and has bilateral tender inguinal nodes; examination shows several shallow ulcers and a few intact vesicles on the vulva. She has no previous similar episodes and no generalized rash or painless ulcer. Which investigation is most appropriate to confirm the diagnosis?