Kawasaki Disease Related to Covid-19
Considerable confusion surrounds a recently recognized complication of Covid-19 in young children and adolescents. Since its original description in April 2020 it has been variously referred to as Kawasaki Disease, Toxic Shock Syndrome and Cytokine Storm. More recently the name has been changed from Pediatric Inflammatory Multisystem Syndrome to Multisystem Inflammatory Syndrome in Children.
Without Symptoms of Covid-19
Children generally remain free of symptoms during their infection with the coronavirus. Signs and symptoms of Kawasaki Disease typically manifest in the convalescent phase several weeks after the infection resolves. It appears the immune system once stimulated to control the virus continues to spiral out of control and attacks tissues throughout the body.
Children with Kawasaki Disease rapidly deteriorate quite rapidly from apparently healthy to quite ill and obviously toxic. Among the initial manifestations of Kawasaki Disease are fever, skin rash, abdominal symptoms and circulatory problems. The fever tends to be substantial often reaching 102-104 degrees Fahrenheit. It rarely responds to either acetaminophen or ibuprofen.
Abdominal symptoms include pain, diarrhea, vomiting and loss of appetite. Skin abnormalities include cracked, reddened and swollen lips together with non-specific patchy erythema involving the torso and extremities. The palms and soles may be bright red with brawny, non-pitting swelling of the hands and feet. Reddening of the eyes may mimic conjunctivitis.
Circulatory problems appear in varied fashion. A fast heart beat or tachycardia almost universally occurs with arrhythmias often following. The heart suffers from the immune attack which presents as myocarditis – involvement of the heart muscle – and often its pericardial sac. Valves may lose normal function and become temporarily incompetent allowing some blood to flow in a backward direction. Blood pressure may become dangerously low as the heart weakens. This generally necessitates ICU supportive care.
Of extreme concern, the immune hyper-reactivity may attack the arteries and lead to temporary of permanent damage. As many as 25% of children with typical Kawasaki Disease develop localized dilations or aneurysms of their coronary arteries. Some even suffer a heart attack. Vascular disease seems to target the endothelial cells lining the vessels. This may lead to lack of oxygenated blood flowing to the intestines and serves as the origin of some of the abdominal complaints.
Abnormalities in blood clotting manifest as neurologic, cardiac or kidney malfunction. Many of the children require ICU care. Interestingly while pulmonary manifestations dominate adult Covid-19 disease, lungs tend to be much less severely affected in Kawasaki Disease. In children ICU admission and mechanical ventilation generally result from circulatory disturbances rather than pulmonary complications.
Significant laboratory abnormalities exist demonstrating immune system over-reactivity and organ dysfunction. Elevated levels of cytokines indicate overbearing activity of the body’s innate and adaptive immune systems.
Supportive medical care requires the correct amount of intravenous fluid coupled with attention to each of the organs under attack. Treatment must be individualized since manifestations vary from child to child. Among the options are anti-inflammatory drugs including corticosteroids and intravenous immune globulin. Some require more targeted blocking of specific cytokines as these chemical messengers act in a domino like fashion and cause progressive harm.
Fortunately this syndrome still appears rather uncommon considering all of the children infected with the virus. Most children with Kawasaki Disease will be discharged from the hospital in about one week. At this time long lasting complications appear unusual however our experience with the syndrome is still limited.
Kawasaki Disease Not in China
Interestingly this condition was initially recognized in Europe several months after the coronavirus first appeared in China. For unknown reasons, Kawasaki Disease seems to spare China and its neighboring countries. Susceptibility in Europe and America may be due to a genetic predisposition, a mutation in the virus or some unknown reason. At present this remains to be more fully explored.