Question

Chlamydia trachomatis serovars D-K cause:

• A. Arteriosclerosis
• B. Trachoma
• C. Lymphogranuloma venereum
• D. Urethritis

Hint:

A-C causes trachoma, D-K causes genital infections such as urethritis, L1-L3 causes LGV.

Answer 1

The Correct Option is D

Step 1: Recall that Chlamydia trachomatis has different serovars for different diseases.
Chlamydia trachomatis is grouped into serovars (strain types) based on small differences in a surface protein, and each group of serovars tends to cause a different disease.

Step 2: Match each serovar group to its disease.
Serovars A, B, Ba, and C cause trachoma, a chronic eye infection that can scar the cornea and cause blindness, spread mainly by direct contact and flies in poor-hygiene settings. Serovars D through K cause genital tract infections, non-gonococcal urethritis, cervicitis, and also adult inclusion conjunctivitis and neonatal pneumonia if passed from mother to baby during birth. Serovars L1, L2, and L3 cause lymphogranuloma venereum, an invasive infection of lymph nodes spread by sexual contact.

Step 3: Apply this to the question.
The question asks specifically about serovars D through K, which sit squarely in the genital infection group. The most common and classic disease from this group is non-gonococcal urethritis.

Step 4: Rule out the other options.

(1) Arteriosclerosis: Not caused by Chlamydia trachomatis at all, this is a disease of artery walls with no infectious cause from this organism.

(2) Trachoma: Caused by serovars A, B, Ba, and C, not D-K.

(3) Lymphogranuloma venereum: Caused by serovars L1, L2, and L3, not D-K.

Final Answer:
Serovars D through K of Chlamydia trachomatis cause urethritis and other genital tract infections.
\[ \boxed{\text{Urethritis}} \]