Tuberculin Positivity in Kawasaki Disease: An Unusual Occurrence

Abstract

To the Editor:A 3-y-old girl presented with high grade fever, irritability, red eyes, lips and tongue and a pruritic rash. She had conjunctival injection, red, cracked lips, ‘strawberry tongue’, edematous hands and feet, and an erythematous, popular rash on the trunk, face and extremities, sparing the palms and soles with classical periungual desquamation. Mobile, non-tender, cervical lymph nodes were palpable. There was erythema and induration at the site where tuberculin had been administered 4 wk ago (Fig. 1). The BCG scar site was normal. Rest of the examination was unremarkable. She had anemia, leukocytosis, thrombocytosis and high erythrocyte sedimentation rate (57 mm) and C reactive protein (92.95 mg/L). Urine showed 7–8 leucocytes per high power field; culture was sterile. Echocardiogram did not reveal any coronary artery abnormalities. Due to the presence of typical features, a diagnosis of Kawasaki disease (KD) was made. Intravenous immunoglobulin was given followed by aspirin. Tomisaku Kawasaki, first reported reactivation of the BCG vaccination site in children with KD. Erythema at the BCG site is reported in upto 50 % of children with KD [1]. However, it has been an uncommon finding in reports from India. The first child with KD and erythema at both BCG and tuberculin administration sites was reported by Kadowaki et al. [2]. Beretto et al. reported tuberculin skin test to be a highly sensitive and specific diagnostic test for KD [3]. They observed that children with acute KD had swelling at the site of previous BCG vaccination or an erythematous reaction at BCG inoculation sites if given during acute KD. They compared tuberculin skin tests in typical KD patients and patients with other febrile illnesses and found that all KD patients had a positive tuberculin skin test. However, a similar study by Kollmann et al. did not support these findings [4]. Skin lesions at the site of BCG or tuberculin administration have been ascribed to molecular mimicry between a mycobacterial heat shock protein (HSP-65) and human homologue HSP 63. Mice inoculated with BCG followed by a crude extract ofMycobacterium intracellulare (cMI) developed coronary arteritis, whereas control animals inoculated with only cMI or BCG did not, suggesting that the immune response to the mycobacteria probably induced autoimmune damage to the vascular wall [5]. In countries with universal BCG vaccination, skin changes at the site of BCG or tuberculin inoculation can be a valuable aid in diagnosis of KD.