Chancroid is caused by which organism?

Chancroid is caused by which organism?

• A. Haemophilus ducreyi
• B. Treponema pallidum
• C. Staphylococcus aureus
• D. Neisseria gonorrhoeae

Answer: (A)

Chancroid is caused by Haemophilus ducreyi, a small gram-negative coccobacillus. This organism produces a painful genital ulcer with ragged borders and purulent exudate, commonly accompanied by tender inguinal lymphadenopathy, which helps distinguish chancroid from other STIs. Treponema pallidum causes a painless chancre typical of syphilis, while Neisseria gonorrhoeae presents with urethral or cervical discharge rather than a painful ulcer, and Staphylococcus aureus is not a typical cause of chancroid. Thus Haemophilus ducreyi fits the clinical picture best.

Chancroid is caused by Haemophilus ducreyi, a small gram-negative coccobacillus. This organism produces a painful genital ulcer with ragged borders and purulent exudate, commonly accompanied by tender inguinal lymphadenopathy, which helps distinguish chancroid from other STIs. Treponema pallidum causes a painless chancre typical of syphilis, while Neisseria gonorrhoeae presents with urethral or cervical discharge rather than a painful ulcer, and Staphylococcus aureus is not a typical cause of chancroid. Thus Haemophilus ducreyi fits the clinical picture best.