Background: Kawasaki disease (KD) is an acute febrile illness characterized by systemic vasculitis of unknown etiology. A BCG reactivation (BCGitis) is not included in the classical clinical criteria for KD. BCGitis recently has been recognized as a clinical marker of incomplete KS in younger children in countries where BCG vaccination is mandatory.
Objectives: To assess the frequency of BCGitis in the clinical profile of patients diagnosed with KD in a Mexican third level Children’s Hospital and its association with the presence of coronary artery abnormalities. (CAA)
Material and Methods: An observational, comparative, retrospective and case control study of all patients diagnosed with KD at our Institution between August 1995 and May 2014 was performed. The clinical presentation, laboratory results, treatment used and coronary artery abnormalities in the BCG-reactive [BCG(+)] and BCG-nonreactive [BCG(-)] groups were analyzed and compared.
Results: We included 356 patients with KD diagnosed at our institution; 83 had BCGitis. (23.3%) The BCG(+) group was younger than the BCG(-) group, 21.2 ± 22.51 vs 44.33 ± 38.85 months (p < 0.00001) There were 17 (20.48%) incomplete cases in the BCG(+) group compared with 52 (19.11%) in the BCG(-) group without statistical significance. The BCG(+) group had a slightly shorter fever duration before IVGG treatment than the BCG(-) group. Laboratory results showed lower hemoglobin counts, higher white blood cell counts, platelet counts, CRP counts, and ALT counts in the BCG(+) group. The BCG+ group developed CAA in 29 cases and the BCG- group developed CAA in 110 cases without statistical significance. Multivariate analysis showed that younger age at diagnosis (< 24 months) was the only factor significantly associated with a reaction at the BCG inoculation site in KD patients
Conclusions: In Mexico, as a country with a National BCG Vaccination Program and a low incidence of KD, a reaction at the BCG inoculation site could be a useful and early diagnostic sign of KD among younger patients, especially those younger than 24 months of age.