Introduction: - Tomisaku Kawasaki described "mucocutaneous lymph node syndrome" in 1967, he reported 50 children with symptoms distinct from other known childhood illness. It appears that prior to Kawasaki's report Kawasaki's disease was identified only postmortem by pathologists, who termed the illness "infantile periarteritis nodosa". In developed nations it appears to have replaced acute rheumatic fever as the most common cause of acquired heart disease in children. Asians are most commonly affected. Kawasaki's disease occurs almost exclusively in young children, 80% of patients are younger than 4 years. It is rare in children less than 3 months of age but has been reported in neonatal age. The etiology of Kawasaki's disease remains unknown. Clinical and epidemiological aspects of the illness strongly suggest an infectious etiology. A self-limited, generally nonrecurring illness manifested by fever, rash, conjunctival injection, and cervical adenitis fits well with an infectious cause. Conventional methods have failed to yield the causative agent of Kawasaki's disease. Diagnosis continues to be difficult, particularly in young infants, who are also at greatest risk of developing coronary artery sequelae. Without etiologic agent, a diagnostic test cannot be developed.
Pathology: - Kawasaki's disease causes a vasculitis, which is most severe in the medium sized arteries; however careful pathologic examination at autopsy reveals that small arterioles, larger arteries, capillaries, and veins are also affected to a lesser extent.
Clinical Features: - In the absence of diagnostic test diagnosis is based on recognition of the clinical features of the illness, which include fever plus four of the five other principle criteria's without other explanations for the illness.
Diagnostic criteria for Kawasaki's Disease Fever for at least 5 days
Four of the following five signs
Bilateral conjunctival injection
Changes of the oral mucosa (erythematous, dry fissured lips; erythema of the pharynx; strawberry tongue)
Changes of the hands and feet (redness and swelling in the acute phase, periungual desquamation in the subacute phase)
Rash, primarily on the trunk (maculopapular, erythema multiforme, of scarlatiform; not vesicular)
Cervical lymphadenopathy (node diameter, >1.5 cm)
Illness not explained by other known disease process. | Patients with fever and fewer than four of the other principle criteria can be given a diagnosis of the Kawasaki's disease if coronary artery abnormalities develop.
Fever: - It is generally high spiking (104 F or higher) and remittent. The first day of fever is considered the first day of the illness, although patients may have developed one or more other clinical features the day before the onset of fever. The duration of fever is generally 1 -2 week in the absence of treatment but may extend for 3 to 4 weeks. In patients treated with high-dose aspirin at 80-100 mg/kg/day and single 2g/kg dose of intravenous gamma globulin, fewer generally resolves within 1-2 days after the therapy is instituted. Conjunctival Injection: - It is distinctive; the bulbar conjunctivae are much more affected than the palpebral conjunctivae, and exudates are generally not present. It usually begins shortly after the onset of the fever. Anterior uveitis may be present on slit lamp examination. Mucosal changes: - Changes in the mouth and lips are characterized by erythema, dryness, fissuring, peeling, and bleeding of the lips; erythema of the oral and pharyngeal mucosa; and strawberry tongue with prominent papillae and erythema. Skin changes: - Erythema is generally confined to hands and soles and they are markedly swollen. In the subacute stage of illness, periungual desquamation of the fingers and toes is common; however this is not a finding in acute illness. After 1 -2 month of the illness transverse grooves across the nails may develop (Beau's lines). Most common rash is maculopapular erythematous rash, which appears quite nonspecific. A scarlatiform rash and an erythema multifome like rash with target lesions are also seen. Vesicles and bullae are not seen, although fine pustules have occasionally been described, particularly over the extensor surfaces of the extremities. Erythema and desquamation of the groin is generally seen earlier than periungual desquamation and may in fact be present in the acute phase of illness. 11% of children have episodes of recurrent peeling of the skin for several years after their recovery. Cervical Lymphadenopathy: - It is seen in 50 -75% of patients, whereas the other features are estimated to occur in 90% of cases. The node may be erythematous, but it is non-fluctuant and does not yield pus if aspirated. Associated features: - Aseptic meningitis - about one fourth of the patients have 25 - 100 leukocytes/cmm in the spinal fluid, with predominantly lymphocytes and normal glucose levels and normal to mildly elevated protein levels in cerebrospinal fluid. Arthralgia and arthritis - It is more common before the use of intravenous gamma globulin in the treatment of Kawasaki's disease than at present. Arthritis of the hands, knees, ankles and occasionally the hips may be seen in the first week of the illness or may occur during the second to third weeks. Hepatitis with mild elevation of the transaminases may also be seen. Diarrhea, pneumonitis, renal artery stenosis, hemolytic anemia, facial nerve palsy and otitis media may also be seen. Erythema and induration at the site of BCG vaccination is seen in almost one-third cases. Japan Research Committee on Kawasaki's Disease has incorporated this finding into diagnostic criteria's. Unusual Manifestation: - Severe peripheral ischemia with resultant gangrene. A pathogenic mechanism of peripheral gangrene includes severe arteritis of digital or other peripheral small arteries; arteriospasm of peripherial small to medium sized arteries. Atypical Cases: - Not all cases fulfill all classic criteria. Diagnosis of atypical Kawasaki's Disease cases is based on coronary artery aneurysms by echocardiography. Kawasaki disease and acute adenoviral infection can present with many of the same clinical characteristics. A rapid direct fluorescent antigen assay for adenovirus may be a helpful adjunctive test for distinguishing acute adenoviral infection from Kawasaki disease. Cardiovascular manifestations: - Death in Kawasaki's disease is usually due to massive myocardial infarction secondary to coronary thrombosis in areas of coronary artery aneurysm formation. Peak incidence of coronary dilatation or aneurysms occurs within 4 weeks of onset.
Clinical Phases of the Kawasaki's Disease: - | Phase | Characteristics | Duration | | Acute | Fever plus other acute features; myocarditis; pericardial effusion | 1 -2 week | | Subacute | Fever resolution, possible persistence of conjunctival injection and irritability, desquamation of fingers and toes, thrombocytosis, coronary arteritis; risk of sudden death greatest | Untill day 30 of illness | | Convalescent | All clinical signs of illness resolved; lasts until sedimentation rate normalizes | 6 -8 week after onset of illness | Laboratory Features: - Elevated leukocyte count with a predominance of neutrophils or a normal leukocyte count with a left shift is typical on the acute phase of illness. Elevated ESR is almost universally present in acute phase. Normocytic anemia and thrombocytosis in the later stages is common. In acute phase low levels of IgG are reported. In subacute phase elevated levels of IgG, IgM, IgE, IgA have been reported. Echocardiography may provide a non-invasive means of identifying the presence and type of coronary artery disease in patients with Kawasaki disease.
Treatment: - Therapies include intravenous immunoglobulin, ASA, corticosteroids and antithrombotics. Treatment of Kawasaki's disease in the first 10 days of illness with a single 2g/kg dose of IVIG and with aspirin at 80 - 100 mg/kg/day reduces the prevalence of coronary artery abnormalities. This non-specific but highly effective therapy is well accepted. Single dose IVIG is more efficacious than multiple daily doses. Myocardial response to gamma-globulin therapy is associated with rapid improvement in myocardial mechanics, with a high concordance between the clinical and myocardial response to therapy. It has been studied that allele A4 gene protects the children with Kawasaki disease from developing coronary aneurysms after aspirin and gamma globulin therapy. Catheter intervention also is a promising therapeutic strategy in the management of coronary stenosis caused by Kawasaki disease. Coronary artery bypass grafting using the arterial grafts can provide attractive results in patients with obstructive coronary arteries associated with Kawasaki disease. Where there is high risk of thrombosis ticlopidine plus aspirin can be used. Click here for References |
