Study design and rationale to assess Doxycycline Efficacy in preventing coronary Artery Lesions in children with Kawasaki disease (DEAL trial) - A phase II clinical trial.

BACKGROUND: Kawasaki disease (KD) is the most common acquired heart disease in children of the developed world, and triggers progressive coronary artery lesions (CAL) in 30% of cases if left untreated. Despite standard anti-inflammatory treatment for KD, CAL (dilation or aneurysm) still occurs in 5-10% of children, increasing their risk for fatal coronary artery complications. CAL is mediated by enhanced matrix metalloproteinase activity and elastin breakdown induced by the inflammatory process in the coronary artery wall. Doxycycline is an effective inhibitor of matrix metalloproteinases, and has been shown to reduce elastin breakdown and CAL in a mouse model of KD, but has not been evaluated in patients. OBJECTIVE: We aim to evaluate the efficacy of doxycycline in the prevention of CAL in children during the acute phase of KD. DESIGN: This is a phase II prospective, randomized, double-blinded, clinical trial in two steps. In Step 1, any child older than 1month with the diagnosis of KD will be included. Children with KD will be included in Step 2 if they develop coronary artery dilation (z-score≥2.5) within 20days from the onset of fever. Study subjects in Step 2 will be randomized to receive a 3-week course of doxycycline or placebo. EVALUATION: The efficacy of a 3-week doxycycline course during the acute phase of KD will be evaluated by measuring the decline in coronary artery z-scores from baseline with doxycycline treatment compared to placebo. CLINICAL TRIAL REGISTRATION: This study was registered on clinicaltrials.gov (NCT01917721).

Coronary artery dilation in acute Kawasaki disease and acute illnesses associated with Fever.

BACKGROUND: In the absence of a specific test, the diagnosis of clinically incomplete Kawasaki disease (KD) can be challenging. The 2004 American Heart Association guidelines state that the diagnosis of KD is supported by the presence of coronary artery dilation documented by echocardiography. However, the specificity of coronary artery dilation and its prevalence in children with other acute illnesses associated with fever has not been studied. METHODS: A 2-center, prospective study compared the internal diameters and Z-scores (standard deviation [SD] units from the mean internal diameter normalized for body surface area) of the proximal left anterior descending and right coronary arteries measured by echocardiography in febrile children (FC) and children with KD. RESULTS: The median Z-score (interquartile range) of the left anterior descending coronary artery was -0.05 (-0.86, 0.62) and 1.06 (0.36, 2.06) SD units for the 45 FC and the 145 KD patients, respectively (P < 0.0001). For the right coronary artery, the median Z-score was 0.21 (-0.20, 0.87) and 1.04 (0.31, 1.85) SD units for the FC and KD patients, respectively (P < 0.0001). There was no correlation between body temperature at the time of echocardiography and coronary artery Z-score. No febrile child had a coronary artery Z-score ≥ 2.5 SD units. CONCLUSIONS: Z-scores ≥ 2.5 SD units were not observed in our cohort of FC. Therefore, echocardiographic evidence of coronary artery dilation can be used to support the diagnosis of KD.