ID - rashes

Question 1

2 yr old boy brought to clinic by his parents, who are immigrants from Japan. He has fever, bilateral conjunctivitis, strawberry tongue, polymorphous rash, and cervical lymphadenopathy with nodes > 1.5 cm.
What is your diagnosis?
What is your treatment?
What is your education to the parents about long-term sequelae?

Answer 1

~Kawasaki disease
~IVIG, aspirin, warfarin, methylprenisolone
~Coronary complications, e.g. aneurysms, even decades later

Question 2

A 32 year old pregnant woman comes to clinic with a mild fever, malaise, coryza, posterior lymphadenitis, and a maculopapular rash over face, trunk, and extremities.
What is your diagnosis?
What is the causative agent?
She’s not very sick - are you worried at all?
Treatment?

Answer 2

~rubella (German measles)

~togavirus

~the concern isn’t for her, it’s for the fetus - extremely high risk of congenital defects such as deafness, early cataracts & glaucoma, heart defects, etc.

~acetaminophen for fever

Question 3

A 29 year old male stock broker comes to your office complaining of fever, chills, myalgia, and maculopapular rash over wrists, ankles, palms, and soles. HPI is positive for history of camping in the woods.
What is your diagnosis?
What is the causative agent?
Treatment?

Answer 3

~Rocky Mountain Spotted Fever

~R. rickettsii transmitted by tick bite

~doxycycline

Question 4

What causes roseola? What are two other names for this disease? Where does the rash appear?

Answer 4

~HHV-6, 7

~exanthema subitum, sixth disease

~pink maculopapules on chest & trunk that fade in 1-3 days

Question 5

What does parvovirus B19 cause (give two names for the disease)?
How does it present?

Answer 5

~erythema infectiosum (fifth disease)

~”slapped face” appearance - red, flushed cheeks; maculopapules on extremities

Question 6

A 42 year old female teacher who just returned (1 week ago) from a trip to rural Maine is complaining of “summer flu” (myalgia, HA, fatigue) and a red circular lesion with a white area in the middle on her upper thigh; this lesion has been getting bigger.
What do you suspect?
What causes this disease?
What lab tests do you order?

Answer 6

~Lyme disease

~B. burgdorferi transmitted by tick bite

~ESR (will be increased), serologic tests for antibodies

Question 7

Lyme disease has three stages. Describe them with respect to timing and symptoms.

Answer 7

Stage 1: early localized
1 week after bite
red lesion at bite site that expands over several days
myalgia, HA, fatigue

Stage 2: disseminated
days to weeks after bite
secondary lesions similar to first but not at bite site
myalgia, fatigue, neck pain
some pts have cardiac, & neurologic symptoms (e.g. facial palsy)

Stage 3: persistent
months to years later
arthritis at knee, large joints
skin: acrodermatitis chronicum atrophicans

Question 8

A 55 year old male dog trainer presents with abrupt onset of high fever, vomiting, and watery diarrhea, as well as a diffuse macular erythematous rash. His palms and soles are peeling. You treated him a week ago for a burn on his hand, and it turns out that he never changed the bandage.
What is your diagnosis?
What organism causes this?
What will the blood culture results be?

Answer 8

~toxic shock syndrome

~ S. aureus

~blood cultures are negative, because the symptoms are due to TOXIN of S. aureus, not systemic infection by S. aureus.

Question 9

What symptom is pathognomonic for measles?
What causes measles?
Describe the rash of measles.
What is a typical lab finding of measles?

Answer 9

~KOPLIK SPOTS: “table salt crystals” (tiny red spots with white center) on buccal mucosa

~paramyxovirus

~rash: BRICK RED, irregular blotchy maculopapular rash that starts on face/behind ears, moves to trunk, then to extremities, palms & soles (“downward and outward”)

~leukopenia

Question 10

TYPHUS: epidemic and endemic

organisms? insect vectors? mammalian hosts? where found?

Answer 10

Epidemic: Rickettsia prowazekii; louse; humans & flying squirrels. Found in S. America, NE/Central Africa.

Endemic: Rickettsia typhi; flea; rats & opossums. Found worldwide with foci in TX & CA.

Question 11

TYPHUS: epidemic and endemic

severity of illness?

Answer 11

Epidemic: more severe. Intractable HA; prostration; macular rash trunk & axillae; 14-21 days

Endemic: gradual onset, less severe. Fever/HA/chills; macular rash trunk; fades fast; 7-10 days.

Question 12

What organism causes scarlet fever?

Answer 12

group A beta-hemolytic streptococci (S. pyogenes)

Question 13

Describe the rash of scarlet fever.

Answer 13

~diffusely erythematous fine red papules - resembles sunburn
~blanchable
~strawberry tongue
~flushed face
~rash fades in 2-5 days and leaves desquamation