A 22-year-old female presents to the physician with a painful vesicular eruption on her left
labium majus. She describes the pain as burning and stinging. She has a fever of 101F and left-sided
inguinal lymphadenopathy. Which of the following best describes the viral etiology?
- A) DNA; enveloped; linear
- B) DNA; enveloped; circular
- C) DNA; non-enveloped; linear
- D) DNA; non-enveloped; circular
- E) RNA; enveloped; linear
- F) RNA; enveloped; circular
- G) RNA; non-enveloped; linear
- H) RNA; non-enveloped; circular
0 voters
EXP:
This patient has an acute genital herpes infection.
This may be due to either HSV1 or HSV2. The literature has in the past supported a propensity for
HSV1 to cause herpes labialis (oral herpes) and HSV2 genital herpes, but the relationship is not
absolute and considerable overlap exists.1, 2, 3
Primary herpes infection
• Primary (first-time) infection often presents more severe than subsequent flareups, and is
frequently accompanied by fever and regional adenopathy.4
• Systemic symptoms, including headache, fever, myalgia, and backache occur in about 70% of
women and 40% of men.4, 5
The herpesviridae are double-stranded linear, enveloped, DNA viruses.6
This is in contrast to hepatitis B, which is a double-stranded circular, enveloped, DNA virus.7
The USMLE really likes this distinguishing structural detail between herpesviridae and
hepatitis B.
Bottom line: On your USMLE: Herpes is “DNA, enveloped, linear.” Hepatitis B is “DNA,
enveloped, circular.”