Pneumonia masking the presentation of incomplete Kawasaki disease

• Main Authors: DeMars, Kathleen R., Justice, Nathaniel A., MD
• Published: Digital Commons @ East Tennessee State University 2019
• Subjects: Infectious disease; Pediatrics; Kawasaki disease; Pneumonia; Infectious Diseases
• Online Access: https://dc.etsu.edu/asrf/2019/schedule/76

Presentation: A 3 month-old male is referred for admission with a 2-day history of fever, having been diagnosed with pneumonia and prescribed a cephalosporin on the previous day. A blood culture obtained at that time is positive for coagulase negative Staphyloccocus. On exam, he is ill-appearing. He has bilateral conjunctivitis that spares the limbus, non-exudative pharyngitis, and a polymorphic truncal rash. There is no appreciable cervical lymphadenopathy or extremity involvement. A chest x-ray demonstrates a round infiltrate of the left upper lobe, and initial labs reveal a white blood count of 17.5, a C-reactive protein (CRP) of 23.9 mg/dL, and a normal comprehensive metabolic panel. His positive blood culture is deemed a contaminant, and antibiotic coverage for community-acquired pneumonia is given with ampicillin. Diagnostic evaluation: On day 5 of illness, his fevers persist despite broadened antibiotic coverage. Further work-up has ruled out viral respiratory pathogens and Epstein-Barr virus as a cause of persistent fevers. Incomplete Kawasaki disease is suspected due to continued fevers, the presence of three clinical criteria, and further increase in his CRP. He lacks other supplemental laboratory criteria, so an echocardiogram is obtained that shows mild dilation of the left anterior descending artery (LAD) of indeterminate significance. A repeat echocardiogram 2 days later reveals progressive dilation of left main coronary artery (LMCA), LAD, and right coronary artery (RCA). Diagnosis: Dilation of the LAD and RCA confirm a diagnosis of incomplete Kawasaki disease. Within 48 hours of treatment with IVIG and high-dose aspirin, the patient is afebrile with resolving symptoms and a declining CRP. He is discharged on the 9th day of illness on low dose aspirin and a cephalosporin to complete an antibiotic course for concurrent pneumonia. Conclusion & Discussion: This case illustrates the importance of maintaining a high index of suspicion for an incomplete presentation of Kawasaki disease, particularly among infants. The American Heart Association’s guidelines were updated in 2017 to improve recognition of incomplete Kawasaki disease, particularly among infants who are more likely to have an incomplete presentation, abnormalities of the coronary arteries, and a delayed diagnosis. The key to this patient’s diagnosis was the presence of a bilateral conjunctivitis that spared the limbus. A bilateral, non-exudative conjunctivitis that spares the limbus has been recognized as a feature suggestive of Kawasaki disease for the better part of four decades; our review of the literature suggests this feature is highly specific to the diagnosis of Kawasaki disease.