Infectious DZ class review questions
and answers A+ rated
topics - ANS ✔1)
2)
3)
4)
5)
6)
Risk of surgical site infection - ANS ✔
Which of the following is the most effective strategy for decreasing this patient's risk of
transmitting HSV to her partner? - ANS ✔Chronic suppressive natural therapy
(eg, valacyclovir) is the most effective strategy for reducing HSV transmission because it reduces
asymptomatic viral shedding, decreases the number of outbreaks, and shortens outbreak
duration.
Herpes simplex virus transmission can occur with asymptomatic viral shedding and during
prodromal phases and active lesions.
Patients with genital HSV require confirmation with diagnostic testing. The most sensitive and
specific method is with a viral PCR assay
64-year-old man comes to the emergency department due to worsening left lower extremity
pain, swelling, and redness over the past 3 days. The patient has had no trauma. Temperature is
,38 C (100.4 F) and BMI is 35 kg/m2. Physical examination shows diffuse erythema extending up
to the left midcalf with an indistinct border. There is increased warmth, tenderness, and edema
of the left leg. No areas of fluctuation or purulent exudate are present, but the interdigital skin
of the feet is macerated and fissured. Leukocyte count is 15,000/mm3. Infection with which of
the following organisms is most likely responsible for this patient's current symptoms?
A beta-hemolytic streptococci
B candida albicans
C clostridium perfringers
D Pseudomana aeruginosa
E varicella zoster virus - ANS ✔The most common cause of nonpurulent cellulitis is beta-
hemolytic streptococci, particularly group A streptococcus.
Treatment of nonpurulent cellulitis is with systemic antibiotic therapy (eg, cephalexin) for ≥5
days. Well-appearing, afebrile patients can be treated as outpatients.
vs
The most common cause of purulent cellulitis is Staphylococcus aureus.
vs
Candida albicans is a skin commensal that can cause inflammatory, moist, weeping,
erythematous lesions in skin folds. It is not a common cause of acute, spreading cellulitis.
Cellulitis vs. Erysipelas vs Abcess
common skin infections
,vs
Pseudomonas aeruginosa skin infections are most common in those who have had exposure to
a hot tub (hot tub folliculitis) or in patients with diabetes mellitus (eg, diabetic foot infection).
vs
Clostridium perfringens causes gas gangrene after traumatic injury (eg, knife wound, surgery) to
the skin and soft tissue. It is usually characterized by sudden-onset severe pain, bullous skin
lesions, and signs of systemic toxicity/sepsis.
vs
Candida albicans is a skin commensal that can cause inflammatory, moist, weeping,
erythematous lesions in skin folds. It is not a common cause of acute, spreading cellulitis. - ANS
✔
A 24-year-old woman comes to the emergency department due to 2 days of fever. The patient
has no chronic medical conditions. She frequently travels for work as a freelance journalist.
Temperature is 38.3 C (101 F). Physical examination is notable for mild scleral icterus and
splenomegaly. Peripheral blood smear reveals ring-shaped parasites within red blood cells, as
seen in the image above. Which of the following infectious agents is most likely responsible for
this patient's current condition? - ANS ✔dx malaria = plasmodium falciparum
endemic regions, who develop febrile illness
As the parasite disseminates throughout the circulation, it can cause nonspecific symptoms (eg,
fatigue, fever, malaise, headache) and, sometimes, life-threatening complications (eg, seizure,
renal failure, circulatory collapse). Hepatosplenomegaly and signs of anemia and
hyperbilirubinemia (eg, scleral icterus) are often present. The diagnosis is confirmed when
peripheral blood microscopy reveals intraerythrocytic trophozoites with a "diamond ring"
appearance.
, A previously healthy 27-year-old man comes to the clinic due to fever and rash. The patient is a
missionary who recently immigrated from South Africa with his wife and 3 young children. Four
days ago, he developed a high fever and malaise followed by the appearance of multiple
discrete macules on his face, trunk, and extremities. The lesions are pruritic and evolved into
pustules then vesicles. The patient has continued to develop new vesicles as other lesions crust
over and heal. The remainder of the examination is unremarkable. This patient most likely has
an infection with which of the following pathogens?
A HSV
B HPV6: roseola infantum
C parvovirus
D varicella- zoster virus - ANS ✔varicella- zoster virus
a pruritic, maculopapular rash develops and evolves into vesicles. A characteristic finding in
varicella is the development of successive crops of lesions on the face, trunk, and extremities, as
seen in this patient with lesions in different stages of development
----------------------------------------------------------------
vs
Herpes simplex virus (HSV) in adults typically causes severe pharyngitis (primary infection) or a
localized cluster of perioral vesicles (reactivated infection). Although HSV can cause a
disseminated vesicular rash, this typically occurs in immunocompromised patients (eg, HIV). In
addition, the rash is painful with vesicles in the same stage of development.
Patients with genital HSV require confirmation with diagnostic testing. The most sensitive and
specific method is with a viral PCR assay
vs
and answers A+ rated
topics - ANS ✔1)
2)
3)
4)
5)
6)
Risk of surgical site infection - ANS ✔
Which of the following is the most effective strategy for decreasing this patient's risk of
transmitting HSV to her partner? - ANS ✔Chronic suppressive natural therapy
(eg, valacyclovir) is the most effective strategy for reducing HSV transmission because it reduces
asymptomatic viral shedding, decreases the number of outbreaks, and shortens outbreak
duration.
Herpes simplex virus transmission can occur with asymptomatic viral shedding and during
prodromal phases and active lesions.
Patients with genital HSV require confirmation with diagnostic testing. The most sensitive and
specific method is with a viral PCR assay
64-year-old man comes to the emergency department due to worsening left lower extremity
pain, swelling, and redness over the past 3 days. The patient has had no trauma. Temperature is
,38 C (100.4 F) and BMI is 35 kg/m2. Physical examination shows diffuse erythema extending up
to the left midcalf with an indistinct border. There is increased warmth, tenderness, and edema
of the left leg. No areas of fluctuation or purulent exudate are present, but the interdigital skin
of the feet is macerated and fissured. Leukocyte count is 15,000/mm3. Infection with which of
the following organisms is most likely responsible for this patient's current symptoms?
A beta-hemolytic streptococci
B candida albicans
C clostridium perfringers
D Pseudomana aeruginosa
E varicella zoster virus - ANS ✔The most common cause of nonpurulent cellulitis is beta-
hemolytic streptococci, particularly group A streptococcus.
Treatment of nonpurulent cellulitis is with systemic antibiotic therapy (eg, cephalexin) for ≥5
days. Well-appearing, afebrile patients can be treated as outpatients.
vs
The most common cause of purulent cellulitis is Staphylococcus aureus.
vs
Candida albicans is a skin commensal that can cause inflammatory, moist, weeping,
erythematous lesions in skin folds. It is not a common cause of acute, spreading cellulitis.
Cellulitis vs. Erysipelas vs Abcess
common skin infections
,vs
Pseudomonas aeruginosa skin infections are most common in those who have had exposure to
a hot tub (hot tub folliculitis) or in patients with diabetes mellitus (eg, diabetic foot infection).
vs
Clostridium perfringens causes gas gangrene after traumatic injury (eg, knife wound, surgery) to
the skin and soft tissue. It is usually characterized by sudden-onset severe pain, bullous skin
lesions, and signs of systemic toxicity/sepsis.
vs
Candida albicans is a skin commensal that can cause inflammatory, moist, weeping,
erythematous lesions in skin folds. It is not a common cause of acute, spreading cellulitis. - ANS
✔
A 24-year-old woman comes to the emergency department due to 2 days of fever. The patient
has no chronic medical conditions. She frequently travels for work as a freelance journalist.
Temperature is 38.3 C (101 F). Physical examination is notable for mild scleral icterus and
splenomegaly. Peripheral blood smear reveals ring-shaped parasites within red blood cells, as
seen in the image above. Which of the following infectious agents is most likely responsible for
this patient's current condition? - ANS ✔dx malaria = plasmodium falciparum
endemic regions, who develop febrile illness
As the parasite disseminates throughout the circulation, it can cause nonspecific symptoms (eg,
fatigue, fever, malaise, headache) and, sometimes, life-threatening complications (eg, seizure,
renal failure, circulatory collapse). Hepatosplenomegaly and signs of anemia and
hyperbilirubinemia (eg, scleral icterus) are often present. The diagnosis is confirmed when
peripheral blood microscopy reveals intraerythrocytic trophozoites with a "diamond ring"
appearance.
, A previously healthy 27-year-old man comes to the clinic due to fever and rash. The patient is a
missionary who recently immigrated from South Africa with his wife and 3 young children. Four
days ago, he developed a high fever and malaise followed by the appearance of multiple
discrete macules on his face, trunk, and extremities. The lesions are pruritic and evolved into
pustules then vesicles. The patient has continued to develop new vesicles as other lesions crust
over and heal. The remainder of the examination is unremarkable. This patient most likely has
an infection with which of the following pathogens?
A HSV
B HPV6: roseola infantum
C parvovirus
D varicella- zoster virus - ANS ✔varicella- zoster virus
a pruritic, maculopapular rash develops and evolves into vesicles. A characteristic finding in
varicella is the development of successive crops of lesions on the face, trunk, and extremities, as
seen in this patient with lesions in different stages of development
----------------------------------------------------------------
vs
Herpes simplex virus (HSV) in adults typically causes severe pharyngitis (primary infection) or a
localized cluster of perioral vesicles (reactivated infection). Although HSV can cause a
disseminated vesicular rash, this typically occurs in immunocompromised patients (eg, HIV). In
addition, the rash is painful with vesicles in the same stage of development.
Patients with genital HSV require confirmation with diagnostic testing. The most sensitive and
specific method is with a viral PCR assay
vs
