Download Board review - Viral infections

Board review - Viral infections
Rubeola (nine-day or red
measles)
Prodromal symptoms - fever, malaise, dry
(occasional croupy) cough, coryza, conjunctivitis
c clear d/c, marked photophobia
1-2 days p prodromal symptoms - Koplik spots
on the buccal mucosa
Koplik spots - tiny, bluish-white dots surrounded
by red halos
rubeola (nine-day or red
measles)
Day 3 or 4 - blotchy, erythematous, blanching,
maculopapular exanthem appears
Rash begins at the hairline and spreads
cephalocaudally and involves palms and soles
Rash typically lasts 5 - 6 days
Can see desquimation in severe cases
rubeola (nine-day or red
measles)
Patients can be systemically ill
Incubation period 9-10 days
Patients contagious from 4 days prior to the rash
until 4 days after the resolution of the rash
Highly contagious - 90% for susceptible people
rubeola (nine-day or red
measles)
High morbidity and mortality common in children
in underdeveloped countries
Peak season is late winter to early spring
Potential complications - OM, PNA, obstructive
laryngotracheitis, acute encephalitis
Vaccination is highly effective in preventing
disease
rubeola (nine-day or red
measles)
Rubella (german measles)
Little or no prodrome in children
In adolescents - 1-5 days of low-grade fever,
malaise, headache, adenopathy, sore throat,
coryza
Exanthem - discrete, pinkish red, fine
maculopapular eruption - begins on the face and
spreads cephalocaudally
Rash becomes generalized in 24 hours and
clears by 72 hours
rubella (german measles)
Forchheimer spots - small reddish spots on the
soft palate - can sometimes be seen on day 1 of
the rash
Arthritis and arthralgias - frequent in adolescents
and young women - beginning on day 2 or 3
lasting 5-10 days
Up to 25% of patients are asymptomatic serology testing may be necessary to establish
the diagnosis
rubella (german Measles)
Important in establishing the diagnosis if the
patient is pregnant or has been in contact c a
pregnant woman
Peaks in late winter to early spring
Contagious from a few days before the rash to a
few days after the rash
Incubation period 14-21 days
Complications - rare in childhood - arthritis,
purpura c or s thrombocytopenia, mild
encephalitis
rubella (german Measles)
Varicella (chickenpox)
Caused by varicella-zoster virus
Highly contagious
Brief prodrome of low-grade fever, URI
symptoms, and mild malaise may occur
Rapid appearance of puritic exanthem
varicella (chickenpox)
Lesions appear in crops - typically have 3 crops
Crops begin in trunk and scalp, then spread
peripherally
Lesions begin as tiny erythematous papules,
then become vesicles surrounded by red halos
Lesions began to dry - umbilicated appearance,
then surrounding erythema fades and a scab
forms
varicella (chickenpox)
Hallmark - lesions in all stages of evolution
All scabs slough off 10-14 days
Scarring not typical unless superinfected
Cluster in areas of previous skin irritation
Puritic lesions on the skin
Painful lesions along the oral, rectal, and vaginal
mucosa, external auditory canal, tympanic
membrane
varicella (chickenpox)
Occurs year-round, peaks in late autumn and late
winter through early spring
Incubation period ranges from 10-20 days
Contagious 1-2 days prior to rash until all lesions
are crusted over
Complications - secondary bacterial skin
infections (GAS), pneumonia, hepatitis,
encephalitis, Reye syndrome
varicella (chickenpox)
Severe in the immunocompromised host - can be
fatal
Can have severe CNS, pulmonary, generalized
visceral involvement (often hemorrhagic)
Need to get varicella-zoster immunogloblin 96
hours post-exposure to possible varicella
varicella (chickenpox)
Adenovirus
30 distinct types
Variety of infections including conjunctivitis,
URIs, pharyngitis, croup, bronchitis, bronchiolitis,
pneumonia (occ fulminant), gastroenteritis,
myocarditis, cystitis, encephalitis
Can be accompanied by a rash - variable in
nature
Typically can see - conjunctivitis, rhinitis,
pharyngitis c or s exudate, discrete, blanching,
maculopapular rash
adenovirus
Can see anterior cervical and preauricular LAD,
low-grade fever, malaise
Peak season is late winter through early summer
Contagious during first few days
Incubation period 6-9 days
Coxsackie hand-foot-andmouth disease
Brief prodome - low-grade fever, malaise, sore
mouth, anorexia
1-2 days later, rash appears
Oral lesions - shallow, yellow ulcers
surrounded by red halos
Cutaneous lesions - begin as erythematous
macules then evolve to small, thick-walled,
grey vesicles on an erythematous base
Coxsackie hand-foot-andmouth disease
Highly contagious
Incubation period 2-6 days
Lasts 2-7 days
Peak season summer through early fall
If no cutaneous lesions - herpangina
less painful and less intense than herpes
gingivostomatitis
erythema infectiosum (fifth
disease)
Caused by Parvovirus B19
Affects preschool and young school aged
children
Peak incidence in late winter and early spring,
but it is seen year round
Characterized by rash - large, bright red,
erythematous patches over both cheeks - warm,
but non-tender
erythema infectiosum (fifth
disease)
Facial rash fades, then see a symmetrical,
macular, lacy, erythematous rash on the
extremities
Resolution occurs within 3-7 days of onset
Transmitted by respiratory secretions, replicates
in the RBC precursors in the bone marrow
Can cause aplastic crisis in patients with sickle
cell disease, other hemogloblinopathies, and
other forms in hemolytic anemia
erythema infectiosum (fifth
disease)
roseola infantum (exanthem
subitum)
Febrile illness affecting children 6-36 months
Human herpesvirus 6 is causative agent
Symptoms include:
fever, usually >39
anorexia
irritability
these symptoms subside in 72 hours
roseola infantum (exanthem
subitum)
As fever defervenscences, usually an
erythematous, maculopapular rash that appear
on the trunk and then spread to the extremities,
face, scalp, and neck
Occurs year-round
More common in late fall and early spring
Incubation period thought to be 10-15 days
roseola infantum (exanthem
subitum)
Infectious mononucleosis
Acute self-limiting illness of children and young
adults
Caused by EBV
Transmission by oral contact, sharing eating
utensils, transfusion, or transplantation
Incubation period 30-50 days (shorter, 14-20
days, in transfusion-acquired infection)
Don’t usually see “classic mono” in young
children
Infectious mononucleosis
Prodrome - fatigue, malaise, anorexia, HA,
sweats, chills lasting 3-5 days
Symptoms
fever - can have wide daily fluctuations
pharyngitis c tonsillar and adenoidal
enlargement c or s exudate, halitosis, palatal
petechiae
LAD - anterior cervical and posterior cervical in classic cases, generalized LAD toward end
of wk 1
Infectious mononucleosis
Symptoms cont:
splenomegaly - develops in 50% of patients in
2nd-3rd wk
hepatomegaly in 10% of patients
exanthem - erythematous, maculopapular,
rubelliform rash in 5-10% of patients
Infectious mononucleosis
Complications:
pneumonia
hemolytic anemia and thrombocytopenia
icteric hepatitis
acute cerebellar ataxia, encephalitis, aseptic
meningitis, myletis, Guillain-Barre
rarely myocarditis and pericarditis
Infectious mononucleosis
Complications cont:
upper airway obstruction from tonsillar and
adenoidal enlargement
seen more often in younger patients
children < 5 yrs of age c obstruction are
more likely to have secondary OM,
recurrent bouts of OM, tonsillitis, and
sinusitis
splenic rupture
Infectious mononucleosis
Diagnosis:
classic finding - lymphocytosis (50% or more) c
10% atypical lymphocytes
80% or more of patients c elevated liver
enzymes
Monospot - detects heterophil antibodies specific, not as sensitive - 85% of adolescents
+ and fewer younger patients
specific EBV antibody titers and PCR
Infectious mononucleosis
DDx
If fever and exudative tonsillitis predominate
GAS, diphtheria, viral pharyngitis
If LAD and splenomegaly predominate
CMV, toxo, malignancy, drug-induced
mono
If severe hepatic involvement
viral hepatitis, leptospirosis
herpes simplex infections
Primarily involve the skin and mucous surfaces
Can be disseminated in neonates and
immunocompromised hosts
Produces primary infection - enters a latent or
dormant stage, residing in the sensory ganglia can be reactivated at any time
herpes simplex infections
HSV-1
>90% of primary infections caused by HSV-1
are subclinical
more common
HSV-2
usually the genital pathogen
usual pathogen of neonatal herpes
herpes simplex infection
Diagnosis
usually made clinically
can scrap base of vesicle and a special stain Giemsa-stained (Tzanck)
ballooned epithelial cells c intranuclear
inclusions and multinucleated giant
viral cultures take 24-72 hours
Primary herpes simplex
infections
Herpetic gingivostomatitis
high fever, irritability, anorexia, mouth pain,
drooling in infants and toddlers
gingivae becomes intensely erythematous,
edematous, friable and tends to bleed
small yellow ulcerations c red halos seen on
buccal and labial mucosa, tongue, gingivae,
palate, tonsils
primary herpes simplex
infections
Herpetic gingivostomatitis
yellowish white debris builds on the mucosal
surfaces causing halitosis
vesiculopustular lesions on perioral surfaces
anterior cervical and tonsillar LAD
symptoms last 5-14 days, but virus can be
shed for weeks following resolution
primary herpes simplex
infections
Skin infections
fever, malaise, localized lesions, regional LAD
direct inoculation (usually cold sores)
lesions are deep, thick-walled, painful vesicles
on an erythematous base - usually grouped,
but may be single
lesions evolve over several days - pustular,
coalesce, ulcerate, then crust over
primary herpes simplex
infections
Skin infections
most common sites are lips and fingers or
thumbs (herpes whitlow)
eyelids and periorbital tissue infection can lead
to keratoconjunctivitis - dx by dendritic
ulcerations on slit lamp exam
can lead to visual impairment - consult
ophtho
Eczema herpeticum (kaposi
varicelliform eruption)
Onset of high fever, irritability, and discomfort
Lesions appear in crops in areas of currently or
recently affected skin (for those with atopic
eczema or chronic dermatitis)
Lesions begin as pustules, then rupture and crust
over the course of a couple of days
Lesions can become hemorrhagic
Eczema herpeticum (kaposi
varicelliform eruption)
Multiple crops can appear over 7-10 days (like
varicella)
Can be mild or fulminant, depending (in part) on
the underlying dermatitis
If area of involvement is large, can be lots of fluid
loss and potentially fatal
Treat promptly c acyclovir
Risk of secondary bacterial infections
Eczema herpeticum (kaposi
varicelliform eruption)
Recurrent herpes simplex
infection
Triggers include fever, sunlight, local trauma,
menses, emotional stress
Seen most commonly as cold sores
Prodrome of localized burning, itching or stinging
before eruption of grouped vesicles
recurrent herpes simplex
infection
Vesicles contain yellow, serous fluid and are
often smaller and less thick-walled than the
primary lesions
Vesicular fluid becomes cloudy after 2-3 days,
then crusts over
Regional, tender LAD
herpes zoster (shingles)
Caused by varicella-zoster virus
After primary infection, virus lies dormant in
genome of sensory nerve root cell
Postulated triggers include mechanical and
thermal trauma, infection, debilitation as well as
immunosuppression
Lesions are grouped, thin-walled vesicles on an
erythematous base distributed along the course
of a spinal or cranial nerve root (dermatome)
herpes zoster (shingles)
Lesions evolve from macule to papule to vesicle
then crusted over a few days
May have associated nerve root pain - not
common in pediatrics - usually short-lived unless
it involves a cranial nerve root dermatome
+/- fever or constitutional symptoms
Regional LAD common
herpes zoster (shingles)
Thoracic, cervical, trigeminal, lumbar, facial
nerve dermatomes (order of frequency)
If cranial nerve involvement - prodrome of severe
HA, facial pain, or auricular pain prior to the
eruption
Affected patients can transmit varicella, but less
of a problem b/c lesions are often covered by
clothing and the o/p is not involved in most cases
herpes zoster (shingles)
gianotti-crosti syndrome
Papular acrodermatitis
Associated c amicteric hepatitis B, EBV,
echovirus, coxasckievirus, parainfluenza virus,
CMV, and RSV
Most patients between 1-6 years old (range 3
months to 15 years)
Prodrome of low-grade fever and malaise
May be associated c generalized LAD,
hepatomegaly, URI symptoms, and diarrhea
gianotti-crosti syndrome
Lesions appear within a few days - discrete, firm,
lichenois papules c flat tops ranging from 1-10
mm (larger in infants and smaller in older
children)
Papules can be flesh colored, pink, red, dusky,
coppery, or purpuric
Distributed symmetrically over extremities
(including palms and soles), buttocks, and face relative sparing of the trunk and scalp
No mucosal involvement and non-purtitic
gianotti-crosti syndrome
Usually clears in 2-3 weeks, but can last for 8
weeks or more
Lab studies are generally non-specific, but liver
enzymes should be obtained and if abnormal hepatitis B or EBV serology should be done
Treatment is supportive
Steroid creams contraindicated b/c they can
make the rash worse
gianotti-crosti syndrome