Bull's eye dermatoscopy pattern at bacillus Calmette–Guérin inoculation site correlates with systemic involvements in patients with Kawasaki disease

Abstract

For the past decades, although the rash at the bacillus Calmette-Guérin (BCG) inoculation site has been recognized as a diagnostic clue in Kawasaki disease, the present study is the first known one attempting to characterize BCG inoculation by dermatoscopy in Kawasaki disease and correlate the grade of BCG reaction with systemic involvement. Thirty-four patients diagnosed with Kawasaki disease by pediatric specialists were enrolled. We performed detailed history taking, laboratory examination, physical examination and dermatoscopy examinations. Based on the BCG reaction pattern by dermatoscopy, we were able to characterize three patterns: (A) Bull's eye pattern in 18 patients; (B) faint homogenous erythema in nine; and (C) central white patch in seven. Patients from group A exhibited the highest elevation of blood aspartate aminotransferase levels (P < 0.05). Notably, three patients from group A had a significantly dilated coronary artery despite i.v. immunoglobulin injection. We concluded that the bull's eye dermatoscopy sign is not only a useful diagnostic clue but also a severity biomarker in patients with Kawasaki disease.

Erythema and induration of the Bacillus Calmette-Guérin site for diagnosing Kawasaki disease

“…(14) It has been hypothesised that the T-cell system has a significant role in facilitating vascular endothelial cell injury in KD. (15)(16)(17) A recent Taiwanese study in 2016 has attempted to better characterise these changes via dermatoscopy, (11) but further prospective studies of BCG site reactions (either quantified by dermatoscopy or histopathological examination) in patients with KD and other febrile illnesses would be useful to further evaluate this association and its significance. Of note, seven out of nine patients with non-KD febrile illnesses with BCG site reaction or induration were infants.…”

“…(8)(9)(10) A recent Taiwanese study in 2016 characterised and graded the reaction at the BCG site in KD via dermatoscopy. (11) It identified bull's-eye pattern under dermatoscopy as a good clinical clue for systemic involvement, i.e. abnormal elevation of liver enzymes and cardiac complications (dilatation of the coronary arteries).…”

Kawasaki disease: etiopathogenesis and novel treatment strategies

“…In patients who have received Bacillus Calmette-Guerin vaccine, erythema, crusting and induration of the skin at the site of vaccination are considered strong specific indicators of KD [13]. Tseng et al [18] recently attempted to correlate the grade of BCG reaction to the severity of systemic involvement in Kawasaki disease. They reported that severe induration in the form of target lesions was associated with highest elevation of liver enzymes, and the risk of coronary artery dilatations and milder induration in the form of a faint rash or a homogenous white area were associated with lesser degree of systemic inflammation in KD.…”

“…They reported that severe induration in the form of target lesions was associated with highest elevation of liver enzymes, and the risk of coronary artery dilatations and milder induration in the form of a faint rash or a homogenous white area were associated with lesser degree of systemic inflammation in KD. These investigators also indicated that the target lesions could, therefore, even serve as biomarkers of clinical severity of KD [18]. …”

Anemia in Kawasaki Disease: Hepcidin as a Potential Biomarker

“…In addition to standard diagnostic criteria, KD patients may experience a variety of nonspecific clinical features, including uveitis, aseptic meningitis, abdominal pain, gallbladder hydrops, rash at the bacillus Calmette-Guérin inoculation site, impaired liver function, hypoalbuminemia, and anemia [15,17,18,19]. Of these, anemia is the most common clinical feature in KD patients and is thought to have a more prolonged duration of active inflammation [20,21,22,23].…”