Kawasaki disease

Kawasaki disease, also known as mucocutaneous lymph node syndrome, is a disease in which blood vessels throughout the body become inflamed. The most common symptoms include a fever that lasts for more than five days not affected by usual medications, large lymph nodes in the neck, a rash in the genital area, and red eyes, lips, palms or soles of the feet. Other symptoms include sore throat and diarrhea. Within three weeks of the onset of symptoms, the skin from the hands and feet may peel. Recovery then typically occurs. In some children, coronary artery aneurysms may form in the heart after 1–2 years. Kawasaki disease, also known as mucocutaneous lymph node syndrome, is a disease in which blood vessels throughout the body become inflamed. The most common symptoms include a fever that lasts for more than five days not affected by usual medications, large lymph nodes in the neck, a rash in the genital area, and red eyes, lips, palms or soles of the feet. Other symptoms include sore throat and diarrhea. Within three weeks of the onset of symptoms, the skin from the hands and feet may peel. Recovery then typically occurs. In some children, coronary artery aneurysms may form in the heart after 1–2 years. The cause is unknown. It may be due to an infection triggering an autoimmune response in those who are genetically predisposed. It does not spread between people. Diagnosis is usually based on a person's signs and symptoms. Other tests such as an ultrasound of the heart and blood tests may support the diagnosis. Other conditions that may present similarly include scarlet fever and juvenile rheumatoid arthritis. Typically, initial treatment consists of high doses of aspirin and immunoglobulin. Usually, with treatment, fever resolves within 24 hours and there is a full recovery. If the coronary arteries are involved, ongoing treatment or surgery may occasionally be required. Without treatment, coronary artery aneurysms occur in up to 25% and about 1% die. With treatment, the risk of death is reduced to 0.17%. Kawasaki disease is rare. It affects between 8 and 67 per 100,000 people under the age of five except in Japan where it affects 124 per 100,000. It is much less common after the age of five. Boys are more commonly affected than girls. The disorder was first described in 1967 by Tomisaku Kawasaki in Japan. Kawasaki disease often begins with a high and persistent fever that is not very responsive to normal treatment with paracetamol (acetaminophen) or ibuprofen. It is the most prominent symptom in Kawasaki disease, is a characteristic sign of the acute phase of the disease, is normally high (above 39–40 °C), is remittent, and is followed by extreme irritability. Recently, it is reported to be present in patients with atypical or incomplete Kawasaki disease; nevertheless, it is not present in 100% of cases. The first day of fever is considered the first day of illness, and the duration of fever is on average one to two weeks; in the absence of treatment, it may extend for three to four weeks. Prolonged fever is associated with higher incidence of cardiac involvement. It responds partially to antipyretic drugs and does not cease with the introduction of antibiotics. However, when appropriate therapy is started – intravenous immunoglobulin and aspirin – the fever is gone after two days. Bilateral conjunctival inflammation was reported to be the most common symptom after fever. It typically involves the bulbar conjunctivae, is not accompanied by suppuration, and is not painful. It usually begins shortly after the onset of fever during the acute stage of the disease. Anterior uveitis may be present on slit-lamp examination. Iritis can occur, too. Keratic precipitates are another eye manifestation (detectable by a slit lamp but are usually too small to be seen by the unaided eye). Kawasaki disease presents with set of mouth symptoms, the most characteristic changes are the red tongue, swollen lips with vertical cracking and bleeding. The mucosa of the mouth and throat may be bright red, and the tongue may have a typical 'strawberry tongue' appearance (marked redness with prominent gustative papillae). These mouth symptoms are caused by the typical necrotizing microvasculitis with fibrinoid necrosis. Cervical lymphadenopathy is seen in 50% to 75% of people, whereas the other features are estimated to occur in 90% of patients, but sometimes it can be the dominant presenting symptom. According to the definition of the diagnostic criteria, at least one impaired lymph node ≥ 15 mm in diameter should be involved. Affected lymph nodes are painless or minimally painful, nonfluctuant, and nonsuppurative; erythema of the neighboring skin may occur. Children with fever and neck adenitis who do not respond to antibiotics should have Kawasaki disease considered as part of the differential diagnoses. In the acute phase of the disease, changes in the peripheral extremities can include erythema of the palms and soles, which is often striking with sharp demarcation and often accompanied by painful, brawny edema of the dorsa of the hands or feet. This is why affected children frequently refuse to hold objects in their hands or to bear weight on their feet. Later, during the convalescent or the subacute phase, desquamation of the fingers and toes usually begins in the periungual region within two to three weeks after the onset of fever and may extend to include the palms and soles. Around 11% of children affected by the disease may continue skin-peeling for many years. One to two months after the onset of fever, deep transverse grooves across the nails may develop (Beau’s lines), and occasionally nails are shed.