Summary about Disease
Incomplete Kawasaki Disease (also known as Atypical Kawasaki Disease) is a form of Kawasaki Disease (KD) where the patient does not present with all the classic diagnostic criteria. This makes diagnosis more challenging and can lead to delayed treatment, increasing the risk of coronary artery aneurysms. It is crucial to consider Incomplete KD in infants and young children with unexplained fever and signs of inflammation, even if they don't meet all typical KD criteria.
Symptoms
While classic KD presents with fever for 5+ days and at least 4 of the 5 following criteria (conjunctivitis, mucositis, rash, extremity changes, and cervical lymphadenopathy), Incomplete KD presents with fever and fewer than 4 of these criteria. Other symptoms that may suggest Incomplete KD include irritability, diarrhea, abdominal pain, gallbladder hydrops, aseptic meningitis, and elevated liver enzymes.
Causes
The exact cause of Kawasaki Disease, including Incomplete KD, remains unknown. Current research suggests it is likely triggered by an infectious agent in genetically predisposed individuals. It is not considered hereditary or congenital.
Medicine Used
The primary treatment for Incomplete KD is intravenous immunoglobulin (IVIG) and high-dose aspirin. IVIG helps to reduce inflammation and the risk of coronary artery complications. Aspirin is used for its anti-inflammatory and antiplatelet effects. In cases where IVIG is ineffective, other medications like corticosteroids or TNF inhibitors might be considered.
Is Communicable
Kawasaki Disease, including Incomplete KD, is not communicable. It is not spread from person to person.
Precautions
Since the cause is unknown, there are no specific precautions to prevent Kawasaki Disease. However, early diagnosis and treatment are crucial to minimize the risk of complications. Parents should be vigilant about unexplained fever and other concerning symptoms in their children and seek prompt medical attention.
How long does an outbreak last?
Without treatment, the acute phase of Kawasaki Disease, including Incomplete KD, typically lasts 1-2 weeks. However, fever can persist for several days before other symptoms manifest. Treatment with IVIG usually shortens the duration of the illness and reduces the risk of complications.
How is it diagnosed?
Diagnosis of Incomplete KD relies on clinical judgment and laboratory findings. Since the classic diagnostic criteria are not fully met, physicians consider the presence of fever, fewer than 4 classic criteria, and other suggestive symptoms. Elevated inflammatory markers (ESR, CRP), elevated white blood cell count, anemia, and thrombocytosis can support the diagnosis. Echocardiography is crucial to assess for coronary artery abnormalities. Scoring systems, like the Kobayashi score, may be used to predict IVIG resistance.
Timeline of Symptoms
The timeline of symptoms can vary in Incomplete KD, making diagnosis more challenging. Typically:
Days 1-5: Fever is the most prominent symptom, often high and persistent.
Days 5-14: Other symptoms may appear, but they may not be the classic KD criteria. This is the period where Incomplete KD is suspected and investigations are initiated.
After Day 14: If untreated, complications such as coronary artery aneurysms can develop. Treatment (IVIG) is most effective if given within the first 10 days of illness, although it can still be beneficial later.
Important Considerations
High index of suspicion: Pediatricians need a high index of suspicion for Incomplete KD, particularly in infants and young children with unexplained fever.
Early consultation: Early consultation with a pediatric cardiologist or rheumatologist is recommended if Incomplete KD is suspected.
Echocardiography: Echocardiography is essential for detecting coronary artery abnormalities.
IVIG resistance: Some patients do not respond to initial IVIG treatment and may require additional therapies.
Long-term follow-up: Patients with Kawasaki Disease, including Incomplete KD, require long-term follow-up with a cardiologist to monitor for potential coronary artery complications.