By Molly Lewis
Kawasaki disease (AKA mucocutaneous lymph node syndrome) may sound like a rare entity found only in Japan, but it happens more often than you might expect- in the US, 19 children per 100,000 each year! It is a systemic vasculitis that most often affects young kids, and is idiopathic (no known cause). It can be surprisingly difficult to distinguish it from scarlet fever and erythema multiforme. So, here is a helpful mnemonic to remember the criteria for diagnosing Kawasaki’s!
“FEEL My Conjunctivitis”
F = Fever –
For ? 5 days– often high (> 102? F (39? C)).”
E = Edema-
Of the hands and feet- the classic presentation is a child who refuses to walk.”
E = Erythematous rash-
Unfortunately, the rash is quite nonspecific. It is polymorphic (AKA can look like just about anything…), usually being diffuse (over a large portion of the body), maculopapular (small lesions, both flat and raised), and erythematous (red!). It can be “scarlatiniform” (like in scarlet fever- red and sandpapery-feeling, and involving the groin), or it can look like erythema multiforme, with target lesions (dark red spot (macule) inside an area of mild erythema, surrounded by a dark red ring).
One aspect that can point toward Kawasaki’s is desquamation (peeling) of the fingers and toes.”
L = Lymphadenopathy-
The enlarged lymph nodes are most often in the cervical region, and are often unilateral, but they may be bilateral. There must be at least one node that is ? 1.5 cm. (Cervical lymphadenopathy is also seen in scarlet fever).”
My = Mucositis (inflammation of the mucous membranes)
Dry, cracked, swollen lips; red throat and oral mucosa; strawberry tongue (the tongue is bumpy like a strawberry, but – careful! – it starts out white before it becomes red! Strawberry tongue and red throat are also seen in scarlet fever).”
Conjunctivitis = Conjunctivitis!
Nonpurulent (watery- no pus), bilateral, classically with “limbic sparing” (the part of the sclera just around the iris remains white).”
To diagnose Kawasaki’s, the patient must have five days or more of fever, plus 4 of the other 5 criteria.”
Other common findings with Kawasaki’s include sterile pyuria (WBC’s in the urine, without bacteria present) and thrombocytosis (high platelet count- often not seen until late in the disease).”
Although this disease is self-limiting (patients get better without treatment), correct diagnosis and treatment are important because the vasculitis can cause coronary artery aneurysms, possibly resulting in a heart attack when the patient is a young adult! Although giving aspirin to kids is usually avoided due to the possibility of causing Reye Syndrome, aspirin is a mainstay of treatment of Kawasaki’s, along with IVIG. (Also, get an echocardiogram, to see if your patient has developed aneurysms!).”
Do you have questions about the patient presentation, workup, diagnosis, treatment, or follow-up of Kawasaki’s? Post them below!”
Or, do you know a different way to remember Kawasaki’s disease, or to distinguish it from scarlet fever or erythema multiforme? Post it below!
Kawasaki disease information: http://www.cdc.gov/kawasaki/; https://online.epocrates.com/noFrame/showPage.do?method=diseases&MonographId=236&ActiveSectionId=11
Kawasaki disease mnemonic: http://www.usmleforum.com/files/forum/2007/2/219828.php
Desquamation photo: http://aapredbook.aappublications.org/content/1/SEC131/SEC205/F1084.expansion.html
Strawberry tongue photo: http://www.nature.com/bdj/journal/v186/n6/full/4800085a.html
Conjunctivitis with limbic sparing photo: http://nodba.ir/dr.nili.kodak/50011-1–cesec27.htm