Concurrent infections in children with Kawasaki disease: lessons learned over 26 years.

Etiology of Kawasaki disease (KD) remains an enigma despite more than 50 years of extensive research. There is evidence that concurrent infections may play a role in the pathogenesis of KD. The present study reports various infections identified in a large cohort of patients with KD in Northwest India. We reviewed case records of patients with KD from January 1994 to February 2020. Patients with KD identified to have concurrent infection at presentation were analyzed in detail. Of 878 cases of KD during this period, 88 (60 boys, 28 girls; 64 incomplete KD, 24 complete KD) had evidence of concurrent infection. Infective manifestations included superficial and deep-seated abscesses (27.45%), pneumonia (28.4%), gastrointestinal manifestations (29.5%), urinary tract infection (4.5%), and septic arthritis (2.3%). Infectious agents were confirmed in 67/88 patients (76.13%) - these included bacteria (n = 51), viruses (n = 13), fungi (n = 2), and protozoa (n = 1). Among bacteria, infections with Staphylococcus sp. and Streptococcus sp. were the commonest (19/88 and 14/88 patients, respectively). Eighty-one children were treated with intravenous immunoglobulin (IVIg, 2 g/kg) and aspirin. Coronary artery abnormalities (CAAs) were seen in 11/88 patients (12.5%) during the acute phase - these normalized at 6 weeks of follow-up in all patients. To conclude, concurrent infections were seen in 10% of patients with KD at our center. If the clinical presentation suggests KD, one should not exclude the diagnosis even if there is evidence of an accompanying infection. Although 12.5% of patients with infection-associated KD had CAAs, none had persistent CAAs at 6 weeks of follow-up.