Kawasaki disease is an acquired heart disease affecting children mostly in the United States and other developed countries. Also known as lymph node syndrome, this disease strikes 80% of children below five years old. It can cause heart abnormalities such as aneurysms and may lead to thrombosis and stenosis and even death. The major cause of death from this disease is heart attack (myocardial infarction). It is still unknown, though, what causes Kawasaki disease but medical experts are pointing to a microbial agent.
Kawasaki disease was first discovered in 1967 and was identified as “mucocutaneous lymph node syndrome.” It first appeared in 50 Japanese children who developed an unusual illness with fever, rashes, conjunctival injection, cervical lymphadenitis, inflammation of the lips and oral cavity as well as redness and swelling of the hands and feet. This disease was later found to have caused the death of several Japanese children mostly under two years old.
An article by Doctors Kathryn Taubert and Stanford Shulman, in collaboration with the American Heart Association, said that Kawasaki disease has been reported worldwide with boys more often affected. It revealed that although the disease occurs anytime of the year, more cases are reported during winter and spring. In North America, children of Asian blood, notably Japanese and Korean, are those mostly affected. In Japan, 116,848 children have contracted the disease based on 12 surveys conducted from 1970 to 1992.
The Japanese Disease Research Committee and the American Heart Association have come up with a clinical criteria in diagnosing Kawasaki disease. This was done due to the absence of a specific diagnostic test for this particular childhood disease. The criteria is divided into the principal clinical findings as well as other significant clinical and laboratory findings.
The principal clinical findings include fever and at least four of the five major features. The course of this disease is further divided into three clinical phases – acute, subacute and convalescent.
During the acute phase, which lasts from one to two weeks, the patient experiences fever, very red eyes (conjunctival injection), mouth and lip changes, swelling of extremities, rash and enlargement of cervical lymph nodes.
In the subacute phase, covering the time the fever ended until day 25, patients may develop arthritis, arthralgia and thrombocytosis.
The convalescent phase starts normally six to eight weeks after the onset of Kawasaki disease when clinical symptoms have disappeared.
The chronic phase, on the other hand, is significant only in patients who have developed heart problems. The duration may be lifetime because those who experienced heart aneurysm in childhood may also experience it in adulthood.
Meanwhile, findings not found in the major clinical criteria are classified into the cardiac, non-cardiac and laboratory categories. The cardiac findings refer to the heart problems that may occur during the acute phase. These heart manifestations include artery abnormalities, inflammation, a gallop heart rhythm, aneurysms, thrombosis, stenosis or even congestive heart failure.
Non-cardiac symptoms that appear during the first two to three weeks of the disease include irritability among infants and children, arthritis and arthralgia affecting the knees, ankles and hips, diarrhea, vomiting, stomach pain and pneumonitis.
On the other hand, the laboratory findings do not necessarily point to Kawasaki disease but may only help in establishing the diagnosis. These are usually seen during the first two weeks of the illness but normalize within six to eight weeks. They include mild anemia, high neutrophil, albumin and serum immunoglobulin E levels, thrombocytosis and proteinuria