Viral exanthema

• What is a 'exanthem'?


  Eruptive widespread rash
• What are the 6 viral exanthemas? 


  1. Measles
  2. Scarlet fever
  3. Rubella (German measles)
  4. Duke's Disease
  5. Paravirus B19
  6. Roseola Infantum
• What causes scarlet fever?


  Exotoxins from Streptococcus pyogenes (Group A Strep)
• What are the signs & symptoms of scarlet fever?


  Red-pink blotchy rash with rough, sandpaper-like skin -> starts on trunk

  Strawberry tongue

  Red, flushed cheeks

  Fever

  Lethargy

  Sore throat

  Cervical lymphadenopathy
• What is the treatment of scarlet fever?


  Abx for underlying streptococcal infection -> usually penicillin V for 10 days

  Notifiable disease

  Children should be kept off school until 24 hrs after starting Abx
• What are the possible complications of measles?


  Pneumonia

  Diarrhoea

  Dehydration

  Encephalitis

  Meningitis

  Hearing loss

  Vision loss

  Death
• What are the possible complications of rubella?


  Thrombocytopenia

  Encephalitis

  In pregnancy, can lead to congenital rubella syndrome -> triad of deafness, blindness & congenital heart disease
• What is Duke's disease?


  A historically described condition, now believed to be non-specific viral rashes.
• What is parvovirus B19?


  Also known as fifth disease, slapped cheek syndrome & erythema infectiosum

  Caused by parvovirus B19
• What are the signs & symptoms of parvovirus B19 infection?


  Mild fever

  Coryza

  Non-specific viral symptoms -> muscle aches, lethargy

  Diffuse bright red rash on both cheeks

  Few days later, reticular mildly erythematous rash affecting trunk & limbs appears, can be raised & itchy
• What is the treatment of parvovirus B19 infection?


  Symptoms usually fade over 1-2 wks

  Analgesia

  Adequate fluid intake

  Once rash has formed, no longer infectious
• What are the possible complications of parvovirus B19 infection? Who is at risk of complications?


  Aplastic anaemia

  Encephalitis/meningitis

  Pregnancy complications (inc foetal death)

  Hepatitis

  Myocarditis

  Nephritis

  Who is at risk?

  • immunocompromised pts
  • pregnant women
  • pts with haematological conditions
• What is roseola infantum?


  Caused by human herpesvirus 6 (HHV-6), and rarely HHV-7
• What are the signs & symptoms of roseola infantum?

  Presents 1-2 wks after infection with high fever (up to 40), comes on suddenly, lasts for 3-5 days, then disappears suddenly

  May be coryzal symptoms, sore throat & cervical lymphadenopathy

  Rash appears once fever has gone -> mild erythematous macular rash across arms, legs, trunk & face, NOT itchy
• What is the management of roseola infantum?


  Supportive

  Generally do not need to be kept off school/nursery if well enough
• What are some possible complications of roseola infantum?


  Febrile convulsions
• Which viral exanthema is shown in this image?

  Measles/rubella

  
• Which viral exanthema is shown in this image?


  Scarlet fever

  
• Which viral exanthema is shown in this image?


  Erythema infectiosum

  
• Which viral exanthema is shown in this image?

  Roseola infantum

  
• Why are NSAIDs not recommended in chicken pox (Varicella zoster)?

  Increases the risk of necrotising fasciitis