Pediatric emergency medicine trisk 3017 3017

CHF may rarely complicate the acute phase of KD. When this is because of
myocarditis, routine treatment with IVIG generally results in rapid clinical
improvement. Although IVIG therapy involves infusing large volumes of isotonic
solution—2 g/kg of 5% IVIG delivers 40 mL/kg over 8 to 12 hours—improvements in
myocardial contractility compensate for the volume load, and treatment rarely leads to
circulatory deterioration. By the second week of illness, and especially in children with
coronary artery dilatation, ischemia or infarction must be excluded as causes of new
myocardial dysfunction.
Kawasaki Shock Syndrome. An uncommon complication (7% in one study from a
single institution), Kawasaki shock syndrome has been recognized as a complication
that can occur during the acute phase of the illness, unrelated to IVIG infusion. It is
defined as systolic hypotension for age, or signs of poor perfusion. It was noted that the
patients who developed shock syndrome were more likely to be female, to have
laboratory findings consistent with greater inflammation (higher CRP levels), more
severe laboratory abnormalities (e.g., lower platelet counts, hyponatremia,
hypoalbuminemia, and consumptive coagulopathy), and to have impaired cardiac
function. All cases required fluid resuscitation and about half required inotropic
support. These patients seem to have greater incidences of coronary artery
abnormalities and IVIG resistance.
Other Complications. Arthritis occurs in approximately one-third of children with KD.
Because it is rare in many of the conditions that may mimic KD, the presence of
synovitis adds supportive evidence for the diagnosis in ambiguous cases. The arthritis
tends to involve the small joints of the extremities during the acute phase of illness and
the large joints during the second and third weeks. The arthritis of KD is always
nondeforming and self-limited, generally resolving within 30 days. Anti-inflammatory
medications such as ibuprofen are usually effective in relieving symptoms until
spontaneous resolution occurs.
Refractory Kawasaki Disease. KD may recur in 1% to 2% of children within 12
months of diagnosis, and an additional 5% to 10% of children treated with IVIG and
aspirin may respond poorly to IVIG treatment during the initial bout of illness. In fact,
patients who fail to respond completely to IVIG pose the greatest therapeutic dilemma.

Prolonged fever itself correlates with increased risk of developing coronary artery
abnormalities, and fever lasting for more than 14 days identifies a group of children at
risk for developing giant coronary artery aneurysms (internal diameter >8 mm), the
group that is most susceptible to infarction and sudden death.
In cases of persistent, recurrent, or recrudescent KD, there are multiple options,
including retreatment with a second dose of IVIG, 2 g/kg over 8 to 12 hours. The risk
of additional IVIG seems to be minimal, and several studies show a dose response to