fever and rash are not a disease , but it component of many diseases
most of which are benign and self limiting , rarely this combination may lead to life-threatening conditions , so we should know the differential diagnosis by history and examination and investigations
so there are three category according to the cause of fever and rash
1-infections 2-vasculitides 3-hypersinsitivity disorders
laboratory tests should oriented based on history and examination , some rashes are pathognomonic for specific disease such varicella(جدري الماء) , and so , investigation not indicated
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history points :
1-characteristics of rash
2-pruritus,pain,tenderness (present or not)
3-appearance in relation to fever
4-evolution and progression of rash
5-history of ill contacts, recent travel , exposure (to pets ,wildlife,insects), sexual activity
6-medical history (medications , iv drug use)
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examination points :
1-examination should be general assessment to determine severity of illness , including vital signs , height of fever
2-you should look at distribution of rash and its morphology and color , also shouldn't forget enanthems (eruptions on mucosal surface)
3-document the rash nature : macular (flat lesion) , papular (raised or palpable ) , morbilliform (classically used to describe rash of measles ) , also describe coalescence of maculopapular rash into diffuse or sheet-like distribution
4-another important characteristic is whether rash blanches with pressure or not
4-tachycardia , tachypnia , fever , rash may indicate sepsis (particularly if there altered mental status ) and hypotension may indicate septic shock
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rashes caused by childhood infections :
1-macular&papular&maculopapular rash :
macules :red/pink discrete flat areas , blanch on pressure
papule : solid raised hemispherical lesions , usually tiny ,blanch on pressure
cause : rubella (macular only ) , measles, HHV6/7 ,enterovirus , uncommon(scarlet fever ,kawasaki)
2-desquamation rash : dry and flaky loss of surface epidermis , usually in peripheries
cause : post scarlet fever , kawasaki
3-pustular & bullous rash : raised hemispherical lesions >0.5cm in diameter contain clear or purulent fluid
cause : impetigo , scalded skin syndrome(sss)
4-vesicular rash :raised hemispherical lesions <0.5cm ,contain clear fluid
cause : chickenpox , shingles , herpes simplex , hand-foot-mouth disease
5-purpuric & petechial rash : non blanching(test with glass) red/purple spots
cause : meningococcal , Henoch-Schonlein purpura , enterovirus , thrombocytopenia
*mnemonic : Very Sick Person Must Take Double Eggs
v=varicella(chicken pox) first day (rash is often first sign in children )
s=scarlet fever : rash in second day
p=pox (small pox): third day
m=measles (rubella or 14 day measles) forth day *koplik spots appear in pre eruptive phase on second day of fever
t=typhus(salmonella) fifth day
d=dengue : 6th day
e=enteric fever : 7th day
*also note Roseola , the rash appear when fever disappears
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------------------------------------------------------ now we talk in details
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Measles (rubeola): الحصبه
measles infection divided in four phases
1-incubation:7-21 days , from exposure to appearing of symptoms (mean 14 days)
2-prodromal (catarrhal): manifestation of third day prodromal phase are
#cough #coryza(nasal discharge and sneezing) #conjunctivitis
and pathognomonic koplik spot(gray-white sand grain sized dots in buccal mucosa opposite the lower molars) that last 12-24hours
3-exanthematous(rash): the macular rash begin on head (often above hairline) and spread over most body parts in a cephalic to caudal pattern over 24hours , the classical symptoms of cough coryza and conjunctivits occur during secondary viremia of exanthematous phase often accompanied by high fever 40-40.5 C
*cervical lymphangitis , splenomegaly , mesenteric lymphadenopathy with abdominal pain may be noted with the rash
*pnumonia,diarrhea , otitis media more common in infants
*liver involvement more common in adult
4-recovery :rash fade in same pattern (cephalocaudal) and illness severity related to extent of rash
whats modified measles :
modified measles describe mild cases of measles occur in pt with partial protection against measles (vaccinated before 12months of age , infants by transplacental antibody , adult receiving immunoglobulin
whats investigation in meales?
routine laboratory tests non specific and dont aid in diagnosis , but leucopenia is characteristic , in patient with acute encephalitis , the CSF(cerebrospinal fluid ) reveal increased protein , lymphocytic pleocytosis , normal glucose
whats treatment of measles ?
supportive , maintain adequate hydration and antipyretics , high dose of vitamin A supplementation has been shown to improve outcome of infants with measles , the who recommend administration of vitamin A for 2 days to all children with acute measles
whats complications and prognosis of measles ?
otitis media the most common complication , interstitial pneumonia(due to measles virus) can occur , or pneumonia due to secondary bacterial infection (streptococcus , staph aureus , group A streptocicci), myocarditis and mesenteric lymphadenitis are uncommon
what about encephalomyelitis in measles ?
occur in 1-2 per 1000 , usually 2-5 days after rash , early enephalitis are related to direct viral infection of brain tissue , whereas later onset is demyelinating and is due to immunopathologic phenomenon
can measles cause subacute sclerosing panencephalitis ?
or can measles cause death ?
subacute sclerosing panencephalitis is late neurologic complication of slow measles infection , characterized by progressive behavioral/intellectual deterioration , and eventual death , it occur in 1/1,000,000 one per million of cases , and death occure 8-10 years after measles , there is no effective treatment
what the cause of death in measles ?
most frequently from bronchopneumonia or encephalitis , risk increased with : malignancy , severe malnutrition , age under 5 , immunocompromised such as hiv infection ,
but in adult and adolescents , death occur due to subacute sclerosing encephalitis
how to prevent measles infection ?
live measles vaccine prevent infection , the vaccine called MMR *measles mump rubella for children at 12-15months and 4-6 years
can person with HIV take measles vaccine ?
yes , contraindication to MMR vaccine are immunocompromised , or who take immunosuppressive course of steroid (>2mg/kg/day) for >14days , pregnant , or recent administration of immunoglobulin (3-11months depending on dose ) , MMR recommended for all HIV patients without evidence of severe immunosuppression , also recommended for children have cancer in remission phase who haven't take chemotherapy in previous 3 months , or haven't received steroid in past 1 month
what to do after contact with measles infected person ?
susceptible household contacts of pt with measles and other with chronic disease or immunocompromised , the later should receive post-exposure prophylaxis with measles vaccine within 72hrs of exposure , immunoglobulin within 6days of exposure