after we discuss measles in last article ( click here to see ) we will continue our big topic about fever&rash in pediatric
this articles will include :
german measles
erythema infectiosum
roseola infantum
chickenpox
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german measles (rubella or 3-day measles):
the incubation period for postnatal rubella is 14-21days(typically at 16 to 18 ) , the prodromal phase (mild catarrhal symptoms ) may go unnoticed
characteristic signs : retroauricular,posterior cervical and posterior occipital lymphadenopathy accompanied by erythematous maculopapular discrete rash , rash begin in face and sptread to the body lasting 3 days and less prominant than that of measles (also measles start neck as mentioned before)
other manifistation of rubella : pharyngitis , conjunctivitis , anorexia , headache, malaise, low grade fever , polyarthritis(usually in hands especially among adult females and usually resolve without complication
paresthesia and tendinitis also may occur
whats treatment of german measles or rubella :
non specific therapy , routine supportive care (maintain hydration and antipyretic )
whats complication and prognosis of rubella :
if rubella not congenital (not congenital rubella syndrome) , complication are rare ,death rarely occur due to rubella encephalitis
can i prevent rubella infection :
live rubella vaccine prevent infection , this vaccine part of MMR which taken at 12,15 months respectively , and in 4-6 years of age
is rubella vaccine have complication or what are the complication of rubella vaccine ?
yes but in certain people , but it mild , in children complication rarely occur , but post-pubertal females , vaccine will lead to arthralgia in 25% of vaccinated females , and acute arthritis-like symptoms in 10% , these symptoms develop 1-3weeks after vaccination , last 1-3days
is there contraindication to rubella vaccine ?
yes , same as of measles , immunocompromised , people who take corticosteroid in immunosuppressive dose 2mg/kg/day for >14 days , pregnancy , recent administration of immunoglobulin (3-11 months , depending on dose)
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roseola infantum (exanthem subitum):
characteristic by abrupt onset of high grade fever >40 c (last for 3-5 days )
maculopapular rose colored rash , erupts coincidentally with defervescence , it may present earlies ,
rash last for 1-3 days but fade rapidly , *note that rash not present in all infant with HHV-6 infection
what are the manifistation of roseola other than rash and fever?
upper respiratory symptoms , nasal congestion,erythematous tympanic membranes , cough may occur
gastrointestinal symptoms
most children with roseola are irritable and appear toxic
*important note : roseola associated with approximately 1/3 of febrile seizure
whats laboratory and imaging studies in roseola ?
routine laboratory findings non specific
but encephalitis due to roseola , characterized by pleocytosis (30-200 cell/mm3) with mononuclear cell predominance , elevated protein , and normal glucose ( in csf )
differential diagnosis : the characteristic pattern of high grade fever >40c for 3-5days without significant physical finding followed by onset of rash with defervescence of fever , make roseola easily diagnosed , many febrile illness may confused with roseola during pre-eruptive phase , so serious infections should excluded , *note : in roseola most children alert , behave normal , normal daily activities
whats treatment of roseola :
adequate hydration , antipyretics , in immunocompromised , ganciclovir or foscarnet can be used
whats drug treatment for roseola ?
as mentioned , ganciclovir or foscarnet
are there complications in roseola infection and what the prognosis of roseola infection ?
excellent prognosis , few death have been attributed to HHV-6 , in cases complicated by encephalitis or virus associated hemophagocytosis syndrome
are there vaccine to prevent roseola :
no clear guidelines
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erythema infectiosum (fifth disease):
caused by parvovirus B19
incubation : 4-14 days rarely reach 21 days ,
usually begin with mild non-specific illness characterized by fever,malaise,myalgia, headache
the characteristic rash appear 7-10 days later
erythema infectiosum manifested by 1-rash , 2-low grade fever or no fever 3-occasionally pharyngitis and mild conjunctivitis
what is characteristic in erythema infectiosum rash ?
divided in three stages ,
1-initial stage is typically slapped cheek rash with circumoral pallor
an erythematous symmetric,maculopapular,truncal rash appears 1-4 days later , then fade as central clearing takes place giving the second stage
2-second stage :distinctive , lacy , reticulated rash last 2-40 days , may be pruritic rash , doesn't desquamate , and recur with exercise , bathing , rubbing or stress
*erythema infectionsum in slapped cheek appearance can confused with systemic lupus erythematous but easily differentiated by other hx , exam , investigation
*pruritic rash may occur with erythema infectionsum
what are the connection between erythema infectiosum and aplastic crises ?
as mentioned , erythema infectiosum caused by parvovirus , so if children with shortened erythrocyte life span (e.g sickle cell disease) those may develop transient aplastic crisis(ineffective erythroid production) last 7-10 days , symptoms range from fever , malaise , pallor ,headache,lethargy ,git symptoms and respiratory symptoms
CBC finding in pt with erythema infectiosum developed transient aplastic crisis ?
reticulocyte extremely low , hemoglobin lower than usual , transient neutropenia-thrombocytopenia
whats laboratory finding in erythema infectiosum ?
hematologic abnormalities occur with infection of parvovirus include reticulocytopenia lasting 7-10 days , mild anemia , thrombocytopenia , lymphopenia , neutropenia
how can detect parvovirus B19 by investigation ?
PCR and electrol microscopy of erythroid precursors in bone marrow , also serological tests show specific IGM antibody to parvovirus are diagnostic
what are the management of erythema infectiosum ?
no specific , but blood transfusion may required in transient aplastic crisis
intrauterine transfusion has been performed in fetuses with hydrops fetalis due to parvovirus infection
intravenous immunoglobulin may used in immunocompromised one with severe anemia or chronic infection
what are the complications&prognosis of parvovirus -erythema infectiosum ?
excellent prognosis , death associated with transient aplastic crisis is are
*parvovirus B19 no teratogenic , but fetal infection may result in fetal heart failure , hydrops fetalis , fetal death due to erythroid cells infection with pv b19
50% of women in childbearing age susceptable to pv b19 infection , 30% of exposed women develop infection , 25% of exposed fetuses become infected , 10% of those culminating in fetal death
is children with erythema infectiosum need shool exclusion ?
no , because children generally are no infectious when the rash is present
how can prevent erythema infectiosum ?
good handwashing , hygiene help reduce transmission , the greatest risk in erythema infectiosum is on pregnant women , effective control measures are limited
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varicella zoster virus (chickenpox and zoster ):
incubation 10-21 days after exposure (generally 14-16 days)
prodromal : fever , malaise , anorexia may precede rash by 1 day
what is the characteristic features of chickenpox or varicella rash ?
appear initially as small red papules , rapidly progress to nonumbilicated , oval , "tear drop" vesicle on erythematous base , fluid progress from clear to cloudy , vesicles ulcerate , crust , heal
new crops appear for 3-4 days ,
where chickenpox rash start , in which part of the body
unlike measles (rash start on neck) or rubella(rash start postauricular area) , varicella zoster or chickenpox start on trunk followed by head , face , less commonly extremities
what is the number of chickenpox lesions ?
100-500 lesions , all forms of lesions present at same time ,
is chickenpox cause pruritus ?
yes , pruritus universal and marked
* mucosal membrane may involved , generalized lymphadenopathy may occur
*severity of rash varies , generally abate after 3-4 days
when to consider chickenpox mild ?
when there <50 lesions.
what are the symptoms of preeruption phase of zoster ?
intense localized-constant pain and tenderness (acute neuritis) along dermatome, accompanied by malaise and fever
what the characteristic of eruptive phase of zoster ?
eruption of papules , quickly vesiculate , distributed in dermatome or in two adjacent dermatomes , group of lesions for 1-7 days , progress to crusting and healing
what are the area of zoster ?
thoracic- lumber dermatomes typically involved , lesions generally unilateral , accompanied by regional lymphadenopathy
*many groups of blisters occur over arm in child with herpes zoster
what is the differential diagnosis ddx of zoster or varicella zoster or chickenpox ?
the diagnosis of varicella zoster is based on distinctive characteristic of its rash ,
eczema herpeticum or kaposi varicelliform eruption is localized vesicular eruption caused by herpes simplex zoster hsv that develops on skin affected by underlying eczema or trauma
what is the treatment of chickenpox or varicella zoster ?
symptomatic therapy , include
1- antipyretics (non aspirin )
2- cool path
3- careful hygiene
4-acyclovir (not recommended in healthy children without risk(unvaccinated older than 12years , immunocompromised) of secondary infections(pneumonia,encephalitis) , complication)
is acyclovir indicated in varicella zoster chickenpox ?
routine administration not recommended in otherwise healthy children with varicella zoster use of acyclovir , its route , duration depend on host factors and the risk for severe infection - complication , early therapy with antiviral acyclovir (especially 24hours within onset or rash )in immunocompromised persons is effective in preventing severe complications, include pneumonia ,encephalitis , and death from varicella
what are the drug treatment of chicken pox ?
acyclovir or valacyclovir may considered in pt at risk of severe varicella , such as unvaccinated older than 12 years , those with chronic cutaneous or pulmonary disease , receiving shortcourse ,intermittent or aerosolized corticosteroid or receiving long-term salicylate therapy
* the dose of acyclovir used in varicella zoster virus much higher than that used for herpes simplex virus
what is the benefit of acyclovir or valacyclovir in chickenpox ?
accelerate cutaneous healing , hastens resolution of acute neuritis , reduce risk of post-herpetic neuralgia
is there rule for concomitant oral corticosteroid for treatment of zoster or chickenpox ?
controversial
is children with chickenpox should isolated from school ?
children with chickenpox should not return to school until all vesicles have crusted
how to deal with hospitalized patient have chickenpox ?
should isolated in negative pressure room to prevent transmission