Infectious conditions that can mimic Kawasaki disease include periorbital cellulitis, peritonsillar abscess, retropharyngeal abscess, cervical lymphadenitis, parvovirus B19, mononucleosis, rheumatic fever, meningitis, staphylococcal scalded skin syndrome, toxic epidermal necrolysis, and Lyme disease. Kawasaki-like disease temporally associated with COVID-19
In 2020, reports of a Kawasaki-like disease following exposure to SARS-CoV-2, the virus responsible for COVID-19, emerged in the US and Europe. The World Health Organization is examining possible links with COVID-19. This emerging condition was named paediatric multisystem inflammatory syndrome by the Royal College of Paediatrics and Child Health, and multisystem inflammatory syndrome in children by the Centers for Disease Control and Prevention. Guidance for diagnosis and reporting of cases has been issued by these organizations. Classification
Debate has occurred about whether Kawasaki disease should be viewed as a characteristic immune response to some infectious  pathogen, as an autoimmune process, or as an autoinflammatory disease (i.e. involving innate rather than adaptive immune pathways). Overall, immunological research suggests that Kawasaki disease is associated with a response to a conventional antigen (rather than a superantigen) that involves both activation of the innate immune system and also features of an adaptive immune response. Identification of the exact nature of the immune process involved in Kawasaki disease could help guide research aimed at improving clinical management.Inflammation, or vasculitis, of the arteries and veins occurs throughout the body, usually caused by increased production of the cells of the immune system to a pathogen, or autoimmunity.
Aerobic exercise performed for 20 minutes a day, three times a week, is sometimes recommended for patients who can tolerate it. Exercise may have the immediate effect of worsening tachycardia, especially after a meal or on a hot day. In these cases, it may be easier to exercise in a semi-reclined position, such as riding a recumbent bicycle, rowing, or swimming.When changing to an upright posture, finishing a meal, or concluding exercise, a sustained hand grip can briefly raise the blood pressure, possibly reducing symptoms. Compression garments can also be of benefit by constricting blood pressures with external body pressure. Medication
If nonpharmacological methods are ineffective, medication may be necessary. Medications used may include beta blockers, pyridostigmine, midodrine, or fludrocortisone. As of 2013, no medication has been approved by the U.S. Food and Drug Administration to treat POTS, but a variety are used off-label. Their efficacy has not yet been examined in long-term randomized controlled trials.Fludrocortisone may be used to enhance sodium retention and blood volume, which may be beneficial not only by augmenting sympathetically mediated vasoconstriction, but also because a large subset of POTS patients appear to have low absolute blood volume.While people with POTS typically have normal or even elevated arterial blood pressure, the neuropathic form of POTS is presumed to constitute a selective sympathetic venous denervation. In these patients the selective Alpha-1 adrenergic receptor agonist midodrine may increase venous return, enhance stroke volume, and improve symptoms.