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-and-mouth disease

* Brief prodome - low-grade fever, malaise, sore mouth, anorexia
* 1-2 days later, rash appears
o Oral lesions - shallow, yellow ulcers surrounded by red halos
o Cutaneous lesions - begin as erythematous macules then evolve to small, thick-walled, grey vesicles on an erythematous base

Coxsackie hand-foot-and-mouth disease

* Highly contagious
* Incubation period 2-6 days
* Lasts 2-7 days
* Peak season summer through early fall
* If no cutaneous lesions - herpangina
o 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:
o fever, usually >39
o anorexia
o irritability
o 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
o fever - can have wide daily fluctuations
o pharyngitis c tonsillar and adenoidal enlargement c or s exudate, halitosis, palatal petechiae
o LAD - anterior cervical and posterior cervical - in classic cases, generalized LAD toward end of wk 1

Infectious mononucleosis

* Symptoms cont:
o splenomegaly - develops in 50% of patients in 2nd-3rd wk
o hepatomegaly in 10% of patients
o exanthem - erythematous, maculopapular, rubelliform rash in 5-10% of patients

Infectious mononucleosis

* Complications:
o pneumonia
o hemolytic anemia and thrombocytopenia
o icteric hepatitis
o acute cerebellar ataxia, encephalitis, aseptic meningitis, myletis, Guillain-Barre
o rarely myocarditis and pericarditis

Infectious mononucleosis

* Complications cont:
o 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
o splenic rupture

Infectious mononucleosis

* Diagnosis:
o classic finding - lymphocytosis (50% or more) c 10% atypical lymphocytes
o 80% or more of patients c elevated liver enzymes
o Monospot - detects heterophil antibodies - specific, not as sensitive - 85% of adolescents + and fewer younger patients
o specific EBV antibody titers and PCR

Infectious mononucleosis

* DDx
o If fever and exudative tonsillitis predominate
# GAS, diphtheria, viral pharyngitis
o If LAD and splenomegaly predominate
# CMV, toxo, malignancy, drug-induced mono
o 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
o usually made clinically
o can scrap base of vesicle and a special stain - Giemsa-stained (Tzanck)
# ballooned epithelial cells c intranuclear inclusions and multinucleated giant
o viral cultures take 24-72 hours

Primary herpes simplex infections

* Herpetic gingivostomatitis
o high fever, irritability, anorexia, mouth pain, drooling in infants and toddlers
o gingivae becomes intensely erythematous, edematous, friable and tends to bleed
o small yellow ulcerations c red halos seen on buccal and labial mucosa, tongue, gingivae, palate, tonsils

primary herpes simplex infections

* Herpetic gingivostomatitis
o yellowish white debris builds on the mucosal surfaces causing halitosis
o vesiculopustular lesions on perioral surfaces
o anterior cervical and tonsillar LAD
o symptoms last 5-14 days, but virus can be shed for weeks following resolution

primary herpes simplex infections

* Skin infections
o fever, malaise, localized lesions, regional LAD
o direct inoculation (usually cold sores)
o lesions are deep, thick-walled, painful vesicles on an erythematous base - usually grouped, but may be single
o lesions evolve over several days - pustular, coalesce, ulcerate, then crust over

primary herpes simplex infections

* Skin infections
o most common sites are lips and fingers or thumbs (herpes whitlow)
o 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

Board review - Viral infections.ppt