Kawasaki Disease in Pediatric

Kawasaki disease is a systemic vasculitis that predominantly affects children under 5 years old. Although the specific etiological agent remains unknown, it is believed that Kawasaki disease is a response to some form of infection (although it is not transmitted from person to person). Diagnosis is often delayed because the features are similar to those of many viral exanthems.

Strawberry tongue Kawasaki Disease in Pediatric

Diagnosis

The diagnostic criteria for Kawasaki disease are fever for 5 days or more, plus four out of five of the following:

• polymorphous rash

• bilateral (non-purulent) conjunctival infection

• mucous membrane changes, e.g. reddened or dry cracked lips, strawberry tongue, diffuse redness of oral or pharyngeal mucosa

• peripheral changes, e.g. erythema of the palms or soles, edema of the hands or feet, and in convalescence desquamation

• cervical lymphadenopathy (>15 mm diameter, usually unilateral, single, non-purulent and painful) and exclusion of diseases with a similar presentation: staphylococcal infection (e.g.scalded skin syndrome, toxic shock syndrome), streptococcal infection (e.g. scarlet fever, toxic shock-like syndrome not just isolation from the throat), measles, other viral exanthems, StevensJohnson syndrome, drug reaction and juvenile rheumatoid arthritis.

The diagnostic features of Kawasaki disease can occur sequentially and may not all be present at the same time. Moreover, it is recognised that some patients with Kawasaki disease do not develop sufficient features to fulfil the formal diagnostic criteria. Clinical vigilance and recognition of this possibility are necessary to recognise these ‘incomplete’ or ‘atypical’ cases. This is important because the atypical cases are probably at similar risk of coronary complications and require treatment. Other relatively common features include arthritis, diarrhea and vomiting, coryza and cough, uveitis, and gallbladder hydrops. Some patients get myocarditis.

Investigations

All patients should have the following investigations:

• ASOT/anti-DNAase B

• echocardiography (at least twice: at initial presentation and, if negative, again at 6–8 weeks)

• platelet count (marked thrombocytosis is common in second week of illness).

Other tests are not diagnostic or particularly useful. The following may be seen:

• neutrophilia

• raised ESR+CRP

• mild normochromic, normocytic anemia

• hypoalbuminemia

• elevated liver enzymes.

Thrombocytosis and desquamation appear in the second week of the illness or later. Their absence earlier does not preclude the diagnosis.

Management

Patients require admission to hospital if Kawasaki disease is diagnosed or strongly suspected. Intravenous immunoglobulin (2 g/kg over 10 hours) should be given, preferably within the first 10 days of the illness, but should also be given to patients diagnosed after 10 days of illness if there is evidence of ongoing inflammation, for instance with fever or raised ESR/CRP.

Aspirin (3–5 mg/kg once a day) should be given for at least 6–8 weeks. Some give a higher dose (10 mg/kg 8 hourly for the first few days) but this probably adds nothing over immunoglobulin.

Follow up

Pediatric follow up should be arranged on discharge. At least one further echocardiogram should be performed at 6–8 weeks. If this is normal, no further examinations are needed