• enanthem- mucosal lesion
• exanthem- skin rash
• macule- flat, pigmented lesion
• papule- elevated, nodular
• maculopapular- a mix
• vesicle- small blister filled with clear fluid (if large, call it a bulla)
• pustle- blister filled with cloudy fluid (neutrophils)

• pattern of illness more important than rash appearance
• epidemiology- season, exposure
• nature of prodromal illness
• type of lesions
• distribultion of rash and pattern progression
  • centripetal- move centrally toward trunk
  • centrifugal- move away from trunk
• associated symptoms (ex: pruritis)

• measles (rubeola)
• German measles (rubella)
• Scarlet fever (S. pyogenes)
• erythema infectiosum (fifth disease: parvovirus B19)
• roseola infantum (HHV6)

• coxasckieviruses
• chickenpox (VZV)
• HSV

• viral classification- paramyxovirus
  • no animal reservoir
  • only naturally occurs in humans
• epidemiology
  • childhood illness
  • worldwide (rare in US)
  • mainly in winter and spring
• transmission (highly contagious)
  • droplets spread by infected nasopharyngeal secretions
  • contagious up to second day of rash

• infect epithelial cells of respiratory tract
• spread via viremia to RE system, then secondy viremia
• replicate in conjunctiva, respiratory tract, GI, GU, lymphatic system, bv's, and CNS
• multinucleated giant cells in skin, mucosa

• incubation perioid of 10-14 days
• contagious seven days before rash forms and limited transmission after rash appears
• prodrom for 3-5 days coincide with secondary viremia
  • fever, coryza (runny nose), conjunctivitis, cough
  • Koplik's spots

• mucosal lesions typically on bucdal and labial mucosa
• irregular, patchy erythema with central minute bluish white speck with the appearance of a grain of salt

• cause- T cell response to virus infected cells lining capillaries
• course
  • morbilliform (maculopapular)- start 14-18 days after infection
  • initially on face and spread over 3-4 days to involve trunk and limbs
  • may involve palsm and soles
  • rash can be extensive and confluent
  • rash fade in 72 hrs
    • can leave post inflammatory pigmentation that may take 6-8 wks to fade

• respiratory tract involvement with secondary bacterial pneumonia
• transient immune suppression
  • increase risk of other infections
  • diarrheal disease, otitis media
• brain, heart, corneal involvement rarely
• post infectious measles encephalitis
• subacute sclerosing panencephalitis

• dx
  • clinical dx
  • may have associated leucopenia
  • serological- IgM with 4 fold rise in IgG titer in paired (acute and convalescent) sera
• tx
  • no antiviral therapy
  • vitamin A can decrease severity

• childhood illness
• mainly in winter and spring
• nasal droplet spread
• moderately contagious

• replicates in URT and spread to lymph nodes causing lymphadenopathy
• viremia and spread throughout body
• infection may be mild or subclinical
• incubation period 18 days

• prodrom of 1-5 days of mild symptoms
• maculopapular rash spreads from top to bottom (not confluent)
• suboccipital and postauricular lymphadenopathy may be helpful for dx
• respiratory shedding of virus 2 wks after rash onset

• arthritis in small joints of women
• rarely, encephalitis
• congenital rubella syndrome

• acute infection during pregnancy with no maternal immunity
• highest risk of infection for fetus until 20th week of gestation
  • mostly in 1st trimester (mainly first 2 months)
• complications
  • deafness, cataracts/glaucoma, congenital heart defects
  • may persisit in infant eyes three to four years and may be shed one year after birth

• virus isolation rarely done
• rubella specific IgM
• more than 4 fold increase in IgG paired (acute and convalescent sera)

• mostly in kids ages 1-10

• rash associated with group A strep (S. pyogenes)
• associated strains produce erythrogenic toxin
• primary infection predominantly in pharynx
• symptoms
  • abrupt onset of fever, headache, vomitting, sore throat
• signs
  • flushed cheeks
  • circumoral pallor
  • strawberry tongue

• appearance
  • diffuse, sandpaper like rash
  • accentuating skin folds (esp. in antecubital fossa)
• begins 1-4 days after illness begins
• rash proceed to desquamation
• tx- anti-strept antibiotics

Usually without serious complications

• winter/spring
• very common in elemetary school aged children (half infected by age 15)
• respiratory transmission common

• erythema infectiosum
• acute arthritis in adults
• transient aplastic crisis in pts with rapid RBC turnover
• chronic anemia in immunodef.
• fetal demise

• course
  1. 2-3 days with mild prodrome
  2. no symptoms for 7 days
  3. slapped cheek appearance
  4. lacy reticular rash on trunk and extremities
• associated with headache, sore throat, GI complaints
• arthritis unusual

• causative agent- HHV6
• epidemiology
  • infants, young kids
  • spread- contact with saliva
  • transmission commonly in spring/fall

1. abrupt onset of fever
2. associated lid edema, suboccipital adenopathy, and pharyngeal erythema
3. once fever resolves, a pink macular rash appears

• lab abnormalities (prior to rash)
  • atypical lymphocytes
  • leucopenia
• illness usually mild, but complications include encephalitis and seizures
• dx- clinically, but serology can be done
• tx- supportive

• epidemiology
  • summer early fall
  • very common and affect alla ges
  • fecal/oral or respiratory spread
• coxsackievirus
  • hand foot and mouth syndrome (HFM)
  • herpangina

• epidemiology- children under 10 and spread to other family members
• course
  • sore throat and mouth (fever 1-2 days)
  • vesicular enanthem on buccal mucosa, tongue that ulcerates
  • papulovesicular rash
    • mostly hands and feets, but may involve proximal extremities and buttocks
    • may be tender
    • do not evolve to form pustles or scabs

• epidemiology
  • summer outbreaks
  • kids 3-10
• course
  1. fever, sore thrat
  2. vesicular enanthem of soft palate and tonsillar pillars that rapidly ulcerates (usually 2-6 lesions)