Kawasaki disease (KD), also known as cutaneous mucocutaneous lymph node syndrome, was first reported by Tomisaku Kawasaki in Japan in 1967 as an acute febrile rash disease with systemic vasculitis as the main lesion. KD is a major cause of ischemic heart disease in childhood, and its onset is related to race, with a higher incidence in Asians and the highest incidence in Japanese.
It can occur in both infants and children, but 80%-85% of them are within 5 years of age, with a high incidence in infants aged 6-18 months. The ratio of male to female is about 1.3-1.5:1, and it is more frequent in winter and spring. The course of the disease is self-limiting, about 6-8 weeks. The recurrence rate is 2-3%, and sibling morbidity is 1-2%. The death rate is about 0.2-1%, and the cause of death is coronary aneurysm and embolism.
The cause of KD is still unclear, and most scholars believe that it is related to infection. The disease is an immune-mediated systemic vasculitis triggered by a variety of infectious agents in a certain susceptible host.
I. Pathological changes
The vasculitic lesions of this disease can be divided into four phases.
1, Acute phase: 1-11 days, periarteritis, microvascular and small arteritis, medium and large intimal inflammation of arteries.
2.Subacute phase: 11-21 days, aneurysm, thrombosis, medium-sized arterial stenosis, and vessel wall edema.
3.Recovery period: 21-60 days, the inflammation of blood vessels is reduced, and the arteries gradually subside.
4.Chronic phase: after 60 days, scar formation and intimal thickening.
II. Clinical manifestations
1.High fever: the fever duration is more than 5 days, and antibiotic treatment is ineffective.
2. Skin rash: mainly maculopapular rash on the trunk, not itchy, without herpes and crust.
3.Conjunctival congestion of both eyes: no secretion, non-purulent.
4.Mouth and lips: flushed mouth and lips, poppy tongue, diffuse congestion in the mucous membrane of the oral pharynx.
5.Hands and feet: hard edema in the acute stage, erythema at the end of the palm and toes and fingers; membrane-like peeling of the nail bed skin migration begins in the recovery stage.
6.Lymph nodes: enlarged lymph nodes in the neck, non-suppurative.
7.Other: redness of the card scar; flushing and peeling of the perianal area.
III. Laboratory tests
1.Peripheral blood picture: increased white blood cells, mainly neutrophils, about half of the children with anemia, platelet increase from the second week, which can last 4-6 weeks.
2. C-reactive protein (CRP) and sedimentation (ESR) are moderately increased or higher.
3.Electrocardiogram: low voltage, ST-T changes, prolonged P-R interval, arrhythmias such as supraventricular tachycardia, atrial fibrillation, ventricular tachycardia and atrioventricular block, etc.
4.Echocardiography: pericardial effusion, left ventricular enlargement, valvular insufficiency, coronary artery dilatation, coronary artery aneurysm and thrombosis, etc.
5.CT and MRI can assist in the diagnosis of coronary artery lesions.
6.Cardiac catheterization Selective coronary angiography is the gold standard for the diagnosis of coronary artery lesions.
Laboratory tests
1.Urinary routine: leukocytosis, proteinuria.
2.Cerebrospinal fluid: mononuclear cell increase.
3.Liver function: decreased albumin (ALB) and increased transaminase.
V. Diagnosis (Japanese KD Study Course, February 2002)
1. Typical Kawasaki disease
(1) Fever for more than 5 days, plus 4 of the following 5 items.
(1) Bilateral bulbar conjunctival congestion without exudate
(2) flushing of the lips and mouth, poppy tongue, diffuse congestion of the mucous membrane of the oral pharynx
③Hand and foot hard edema in the acute stage, erythema at the end of the palm and toes and fingers; membrane-like peeling of the nail bed skin migration begins in the recovery stage.
④Patchy papule, polymorphic erythema-like or scarlet fever-like rash.
(5) Enlarged lymph nodes in the neck with a diameter of more than 1, 5 cm.
(2) Exclude other diseases
(3) If the fever is only accompanied by the other three, but there is coronary artery aneurysm formation, KD can also be diagnosed.
2. Incomplete KD (incomplete KD)
(1) It refers to fever for 5 days, but only 2 or 3 of the other 5 clinical features are present, excluding scarlet fever, drug allergy syndrome, Stevens-Johnson syndrome, toxic shock syndrome, adenovirus infection, Epstein-Barr (EB) virus infection and other febrile diseases.
(2) Reference items of incomplete KD
(i) Reproduction of erythema at the site of BCG vaccination.
(ii) Significant increase in platelet count.
(③) Significant increase in CRP and ESR.
④Echocardiography showing dilated coronary arteries or increased arterial wall glow.
⑤ heart murmurs (mitral valve incomplete closure or pericardial friction sounds).
⑥ Hypoalbuminemia and hyponatremia.
VI. Treatment of KD in acute stage
1.Intravenous injection of human gammaglobulin (IVIG): gammaglobulin single dose of 2g/kg, intravenous input within 10-12 hours, to achieve good efficacy. It is advocated that early application (within 7 days of onset) is effective. Early application of IVIG can reduce the chance of coronary artery damage to less than 5%.
2.Aspirin: 30-50mg/kg, d, divided into 3-4 oral doses until the fever subsides, until 14 days of illness, change to 3-5mg/kg, d, divided into 2 oral doses, for 8-12 weeks.
3. Treatment of KD non-response
Persistent fever or re-fever even 48 hours after completion of initial IVIG. Most experts recommend giving 1-2g/kg of IVIG again. glucocorticoids can be applied appropriately.
VII. Grading and management of coronary artery damage
1.Grading of coronary artery damage
(1) Grade I: No coronary aneurysm (after 2 weeks).
(2) Grade II: transient coronary artery dilatation that subsides at 1 month.
(3) Grade III: Mild coronary artery dilatation with an internal diameter of less than 4 mm.
(4) Grade IV: moderate size coronary artery aneurysm with an internal diameter between 4-8 mm.
(5) Grade V: Large coronary artery aneurysm with an internal diameter greater than 8 mm.
(6) Grade VI: coronary artery stenosis and myocardial ischemia.
2. Graded management plan for KD combined with coronary artery damage
KD follow-up: 1, 2, 3, 6, 12 months and once a year.
(1) Grade I: No coronary aneurysm (after 2 weeks). Oral ASP for 3 months, no need to restrict activity.
(2) Grade II: subsided at 1 month. Management is the same as grade Ⅰ.
(3) Grade III: Still dilated at 1 month. use ASP until 3 months after normalization of coronary arteries. Restrict activities appropriately.
(4) Grade IV: Antithrombotic therapy, prohibit strenuous activities.
(5) Grade V: antithrombotic therapy, prohibit any activity, and coronary angiography if necessary.
(6) Grade VI: coronary artery stenosis and myocardial ischemia. Clinical symptoms include angina pectoris, ECG shows ischemic changes, and ultrasound shows thrombosis and segmental motion abnormalities. Coronary angiography should be performed when possible to clarify the site and extent of disease. Management is the same as class V.