Childhood: Common Infectious Diseases

SKIN ERUPTIONS

Measles

If an acute exanthematous illness is not accompanied by a dry cough and red eyes, it is unlikely to be measles. Features: blotchy red maculopapular rash + 3 Cs; cough, coryza, conjunctivitis. Diagnosis is usually clinical.

Encephalitis (1 in 1000) is the complication of concern.

Diagnosis: serology or nasopharyngeal aspirate (PCR) or urine PCR

Treatment

• No specific treatment

• Symptomatic (e.g. cough linctus)

• Rest quietly and avoid bright lights

• Stay in bed until fever subsides

• Ample fluid intake

• Exclusions (patient 5 d, non-immunised contacts 14 d)

Prevention

• Combined vaccine at 12 mths and 18 mths

Rubella

A minor illness in children but congenital rubella is still the most important cause of blindness and deafness in the neonate. It is completely preventable.

Postauricular lymphadenopathy and facial rash are features.

Diagnosis: serology for antibodies

Treatment

• Symptomatic

• Rest quietly until well

• Paracetamol for fever and arthralgia

• Exclusions (patient 5 d, contacts nil)

Prevention

• Combined vaccine at 12 mths and 18 mths

Scarlet fever

Caused by the toxin of Streptococcus pyogenes. Treated with phenoxymethylpenicillin: 10 mg/kg up to 500 mg (o) 12 hrly for 10 d.

Viral exanthema (fourth syndrome)

Rubella-like rash, often misdiagnosed. Rash mainly confined to trunk. Child usually well or has mild symptoms. Treatment is symptomatic.

Erythema infectiosum (fifth syndrome)

‘Slapped cheek’ syndrome is caused by a parvovirus. A maculopapular rash mainly on the limbs with bright red flushed cheeks. Diagnosis is by serology (if necessary). A mild illness but a problem in pregnancy. No exclusions.

Roseola infantum (exanthema subitum or sixth syndrome)

Viral infection (human herpes virus 6) of infancy usually 6–18 mths. Prone to febrile convulsions. Rash appears as high temperature subsides. Treatment is symptomatic.

Chickenpox (varicella)

Onset

• Children: no prodrome

• Adults: prodrome (myalgia, fever, headaches) for 2–3 d

Rash

• Centripetal distribution, incl. oral mucosa

• Scalp lesions can become infected

• ‘Cropping’ phenomenon: vesicles, papules, crusting lesions present together

• Pruritic

Treatment Treatment is symptomatic and usually no specific therapy is required.

• Reassurance that lesions do not usually scar

• Rest in bed until feeling well

• Give paracetamol for fever

• Drink ample fluids; keep diet simple

• Solugel to relieve itching

• Daily bathing with lukewarm water and sodium bicarbonate (½ cup added) or Pinetarsol (preferable) in bath water

• Avoid scratching

• Antihistamines for itching if necessary

• If appropriate, valaciclovir or similar agent in patients >14–15 yrs (commence only during ...