A female presents with 3 cm painless ulcer with raised edges on labia majora. Most common cause is

Presence of 3 cm ulcer with raised edges in the labia majora suggests Syphilis. FeaturesSyphilisChancroidLymphogranuloma VenereumDonovanosisAgent Treponema pallidumHemophilus ducreyiChlamydia trachomatis (L1, L2, L3)Calymmatobacterium granulomatisIncubation period 9 - 90 days 1 - 7 days 3 days - 6 weeks 1 - 4 weeks Early lesions Superficial/deep-seated papule Excavated pustule Superficial/deep-seated papule or pustule Elevated papule Edges Sharply, demarcated, elevated, round or oval Undermined, ragged, sloughed or irregular Elevated, round or ovalElevated, irregular serpiginousBaseSmooth, non-purulent, non-vascular Purulent, bleeds easily Variable, Non-vascular Red, velvety bleeds easily with exuberant granulation tissue Induration Firm Soft Firm Firm Pain Uncommon Very tender Variable Uncommon Lymphadenopathy Firm, non tender, shotty, bilateral Tender, loculated, suppurated, unilateral Tender, loculated, suppurated, unilateral PseudobuboesDiagnosis Darkfield microscopy ;SerodiagnosisGram staining Demonstration of LGV as elementary and inclusion bodies; Frie's test Histopathological examination of biopsy ;Staining with Giemsa stain, Wright's stain, Silver stain, Leishman stain TreatmentPenicillin G - Drug of Choice for all stages of syphilisAzithromycin 1 g single oral dose (or) Ceftriaxone 250 mg IM single dose (or) Ciprofloxacin 500 mg bd for 3 daysDoxycycline 100 mg BD for 3 weeksDoxycycline 100 mg BD for 3 weeks(Refer: Essentials in Dermatology, 1st edition)