Practice Questions

The correct option is Neisseria gonorrhoeae. When a newborn passes through a birth canal infected with gonorrhea, the pathogen can infect the eyes, causing ophthalmia neonatorum. Routine prophylactic eye drops (e.g., erythromycin) are given to prevent this.

The correct option is CD4+ T-helper lymphocytes. HIV uses the CD4 receptor to enter and eventually destroy T-helper cells. The loss of these orchestrator cells severely impairs both humoral and cell-mediated immune responses, leading to AIDS.

The correct option is The HSV ulcer is preceded by painful fluid-filled vesicles. Genital herpes begins as painful vesicles (blisters) that rupture to form painful, shallow ulcers. The syphilitic chancre is a single, painless, firm (indurated) ulcer without a vesicular stage.

The correct option is Neonatal exposure to the virus during passage through the birth canal. Genital herpes is generally not transmitted across the placenta (unlike syphilis). Neonatal herpes is acquired via direct contact with infectious lesions in the birth canal, which a C-section bypasses.

The correct option is Herpes Simplex Virus type 2 (HSV-2). HSV-2 infects epithelial cells and then travels retrogradely up sensory nerve fibers to reside latently in the sacral ganglia. Stress or immunosuppression can trigger anterograde transport and recurrent painful blisters.

The correct option is Secondary stage. The secondary stage of syphilis is characterized by systemic spread of the spirochetes, leading to widespread mucocutaneous rashes, classically involving the palms and soles, along with systemic symptoms like fever and lymphadenopathy.

The correct option is Spirochete. Treponema pallidum is a thin, tightly coiled spirochete with endoflagella (axial filaments) that allow a corkscrew motion, enabling it to penetrate intact mucous membranes. Neisseria is a diplococcus.

The correct option is Syphilis. The primary stage of syphilis is characterized by a hard, painless ulcer known as a chancre at the site of infection. Genital herpes presents with painful blisters/ulcers. Gonorrhea typically presents with discharge, not an ulcer.

The correct option is Pelvic inflammatory disease (PID). In females, gonorrhea is often asymptomatic initially but can ascend to the uterus and fallopian tubes, causing PID. This leads to scarring, infertility, and ectopic pregnancy. Ulcers are typical of syphilis; blisters of herpes; cervical cancer is associated with HPV.

The correct option is Neisseria gonorrhoeae. The clinical presentation of purulent discharge and dysuria, combined with the microscopic finding of intracellular Gram-negative diplococci (coffee-bean shape), is the classic diagnostic hallmark of gonorrhea. Treponema is a spirochete, while HSV and HIV are viruses.