Kawasaki disease: Causes and symptoms

Named after its Japanese discoverer, Kawasaki Disease is a self limiting childhood febrile illness which most of the time appear benign. The late discovery of its potentially serious complications if left untreated fueled more research in tackling this disease.

The cause for this disease or the aetiology is still unknown. But, the medical fraternity in its research have associated the disease to infections, both viral and bacterial, that activate the common immune pathways in precipitating this inflammatory condition. The focus is mainly on respiratory associated infections.

At its very onset, it is difficult to distinguish Kawasaki Disease from any other febrile infection of childhood. When discussing the symptoms, it is vital to know the epidemiology of the disease, or the prevalence within the population, to suspect the disease before it becomes complicated.

The disease is more prevalent among children of 18-24 months and said to be associated more with the Japanese-American population. The disease is more prevalent in male children than in female children.

Diagnosis of the disease is done using a criterion which involves clinical symptoms as well as laboratory investigations. It is important to be on the lookout for these symptoms as it would be critical in the early detection or even to arouse suspicion. Following symptoms are in the order of its occurrence among the diseased patients.

Fever: Being the most prominent symptom and a symptom that indicates the disease progress will not resolve to antibiotic therapy and will persist more than 5 days. The fever will be high (39 C) and spiky.

Changes in lips and oral cavity: Apart from the fever, redness of the throat, dry/swollen and fissured lips and more importantly the 'Strawberry tongue' is a characteristic feature of Kawasaki Disease if associated with other common features. Bleeding from such sites might also be noticed in these patients.

Red eyes: The conjunctivitis of both eyes without any purulent discharge occurs in most of the patients.

Rash: Non vesicular, red rash would appear in most of the instances and it may be generalized or limited to groin or lower extremities.

Peeling of skin: 1-2 weeks after the onset of the illness, it is possible to witness the peeling of skin and oedema with children refusing to bear weight.

Stiff neck: This might lead to pre-assumption and treatment for Meningitis. Although, it is found that aseptic meningitis is quite common among Kawasaki patients.

from the above symptoms, inflammation of the testis, urethra and joints might occur. It might also be associated with non specific symptoms like abdominal pain, vomiting and diarrhea. 

Although this article mainly deals with symptoms of the Kawasaki Disease, it would be incomplete if its dreaded complications are not mentioned. Out of which, Coronary artery aneurysm and clot formation is life threatening. The swelling of the main blood vessel of the heart and formation of a blood clot can lead to dysfunction of the cardiac musculature and its function and cause sudden myocardial infarction and death.

The appearance of these symptoms will occur in 4 distinguished stages.

Acute phase: The fever and rash with irritability will be more elaborate while oral cavity changes will get apparent. It usually last for 1-2 weeks.

Sub acute phase: Beginning of complications occur in this stage where fever usually subside but the aneurysm formation starts. It usually lasts for 4 weeks and persistent irritability, red eyes and other symptoms will be noticed.

Convalescent phase: Even though the symptoms subside and laboratory findings also resolve the main feature will be the persistence of the coronary artery aneurysm.

Chronic phase: This want be significant unless cardiac complications have occurred.

By looking at these symptoms, it is obvious that the diagnosis would not be easy or straightforward as some of the diseases. Although most patients will recover uneventfully, a vigilant eye will prevent disaster if Kawasaki Disease is not suspected in such patients.