Prevalence, Clinical Profiles, and Prognosis of Stiff-Person Syndrome in a Japanese Nationwide Survey.

BACKGROUND AND OBJECTIVES: To elucidate current epidemiologic, clinical, and immunologic profiles and treatments of stiff-person syndrome (SPS) in Japan. METHODS: A nationwide mail survey was conducted using an established method. Data processing sheets were sent to randomly selected departments of internal medicine, neurology, pediatrics, psychiatry, and neurosurgery in hospitals and clinics throughout Japan to identify patients with SPS who were seen between January 2015 and December 2017. RESULTS: Thirty cases were identified as glutamic acid decarboxylase 65 (GAD65)-positive SPS cases on the basis of detailed clinical data of 55 cases. Four patients had α1 subunit of glycine receptor (GlyR) antibodies, and 1 patient had both GAD65 and GlyR antibodies. The total estimated number of patients with GAD65-positive SPS was 140, and the estimated prevalence was 0.11 per 100,000 population. The median age at onset was 51 years (range, 26-83 years), and 23 (76%) were female. Of these, 70% had classic SPS, and 30% had stiff-limb syndrome. The median time from symptom onset to diagnosis was significantly longer in the high-titer GAD65 antibody group than in the low-titer group (13 months vs 2.5 months, p = 0.01). The median modified Rankin Scale (mRS) at baseline was 4, and the median mRS at the last follow-up was 2. Among the 29 GAD65-positive patients with ≥1 year follow-up, 7 received only symptomatic treatment, 9 underwent immunotherapy without long-term immunotherapy, and 13 received long-term immunotherapy such as oral prednisolone. The coexistence of type 1 diabetes mellitus and the lack of long-term immunotherapy were independent risk factors for poor outcome (mRS ≥3) in the GAD65-positive patients (odds ratio, 15.0; 95% CI 2.6-131.6; p = 0.001; odds ratio, 19.8; 95% CI 3.2-191.5; p = 0.001, respectively). DISCUSSION: This study provides the current epidemiologic and clinical status of SPS in Japan. The symptom onset to the diagnosis of SPS was longer in patients with high-titer GAD65 antibodies than in those with low-titer GAD65 antibodies. The outcome of patients with SPS was generally favorable, but more aggressive immunotherapies are necessary for GAD65-positive patients with SPS.

Nationwide clinical and epidemiological study of large-vessel vasculitis in Japan in 2017.

OBJECTIVE: We conducted a nationwide epidemiological study to estimate the number of patients with Takayasu arteritis (TAK) and giant cell arteritis (GCA) in Japan and to describe the clinical characteristics of these patients. METHODS: The first survey was designed to estimate the number of patients with TAK and GCA who were treated at medical institutions in Japan in 2017. The second survey was designed to collect data on the clinical characteristics of the patients who were reported in the first survey. RESULTS: Of the 3495 institutions selected for the first survey, 1960 (56.1%) responded. The number of patients with clinically diagnosed TAK and GCA was estimated to be 5320 (95% confidence interval, 4810-5820) and 3200 (95% confidence interval, 2830-3570), respectively. Aortic regurgitation was reported in 35% of patients with TAK, and eye-related comorbidities were observed in 30.4% of patients with GCA. The common carotid and internal carotid arteries were the most frequently involved in patients with TAK (62.7%). Subclavian artery lesions and thoracic or abdominal aorta lesions were reported in 31% and 42.6% of patients with GCA, respectively. CONCLUSIONS: The number of patients with TAK and GCA was estimated simultaneously, and significant differences in clinical characteristics were observed between the two diseases.

Differences in Sensitivity Between the Japanese and Z Score Criteria for Detecting Coronary Artery Abnormalities Resulting from Kawasaki Disease.

No studies have assessed differences between the Japanese and Z score criteria in the echocardiographic detection sensitivity of coronary artery (CA) abnormalities using large-scale data containing samples from multiple facilities engaged in daily clinical practices of Kawasaki disease (KD). We analyzed data from the 25th Japanese nationwide KD survey, which identified 30,415 patients from 1357 hospitals throughout Japan during 2017-2018. Hospitals were classified according to their use of Z score criteria. We assessed differences in hospital and patient background factors and compared the prevalence of CA abnormalities among groups using the Z score criteria. Multivariable logistic regression analyses were performed to evaluate differences in the detection sensitivity for CA abnormalities. The Z score criteria were more likely to be utilized in larger hospitals with more pediatricians and cardiologists. Even after controlling for potential confounders, detection sensitivities by the Z score criteria were significantly higher than by the Japanese criteria in patients with CA dilatations (adjusted odds ratio (95% confidence interval) 1.77 (1.56-2.01)) and aneurysms (1.62 (1.17-2.24)). No significant difference was found in patients with giant CA aneurysms. Compared with the Japanese criteria, the Z score criteria were significantly more sensitive for detecting patients with CA dilatations regardless of age, and for those with CA aneurysms only in patients aged ≤ 1 year. Our results indicate that differences in the detection sensitivity for CA abnormalities between the Z score and the Japanese criteria were dependent on the CA size and patient age.

Incidence of Kawasaki Disease Before and After the COVID-19 Pandemic in Japan: Results of the 26th Nationwide Survey, 2019 to 2020.

Importance: Global studies have reported that the incidence of Kawasaki disease (KD) declined during the COVID-19 pandemic. These studies suggest that the global pandemic and its accompanying mitigation measures may provide an important opportunity to explore the hypothesis of a KD pathogenesis. Objective: To compare changes in KD incidence in Japan before and after the start of the COVID-19 pandemic. Design, Setting, and Participants: This cohort study was conducted using the data set from Japan's 26th nationwide KD survey that obtained information on patients who were diagnosed with KD in Japan from January 1, 2019, through December 31, 2020. Main Outcomes and Measures: Kawasaki disease incidence rates were calculated by referring to the national population data in the vital statistics data for Japan. Results: A total of 28 520 patients were identified (16 236 male individuals [56.9%]; median [IQR] age, 26 [14-44] months). A total of 17 347 patients were diagnosed with KD in 2019 and 11 173 were diagnosed in 2020, representing a 35.6% reduction in the number of patients diagnosed in 2020 compared with the previous year. Patient distributions for days of illness at the first hospital visit were almost identical in 2019 and 2020, suggesting that the decrease in KD incidence likely was not associated with pandemic-related delays in seeking treatment. The proportion of patients diagnosed with KD who were younger than 12 months was significantly larger in 2020 than in 2019 (21.6% vs 19.4%; P < .001). Compared with KD incidence among younger patients, the incidence among those 24 months and older declined rapidly after initiation of COVID-19 special mitigation measures, with a greater percentage reduction (58.3% reduction in July), but rebounded faster after the end of the special mitigation period. By contrast, the incidence among patients younger than 12 months declined moderately after the initiation of the special mitigation period, with a lower percentage reduction (40.3% reduction in October), and rebounded at a later phase. Conclusions and Relevance: In this cohort study, the number of patients diagnosed with KD decreased by approximately one-third across Japan in 2020, with no indication that parents avoided a hospital visit. Differences in KD incidence reduction patterns before and after the initiation of COVID-19 pandemic mitigation measures were found in patients with KD aged younger than 12 months compared with those 24 months or older, suggesting a potential KD pathogenesis involving transmission among children.

Follow up of Kawasaki disease based on nationwide survey data in Japan: Mortality among those with a history of Kawasaki disease in Japan: Results of a 30-year follow up: Mortality among those with a history of Kawasaki disease in Japan: Results of a 30-year follow up.

BACKGROUND: The long-term prognosis of those with a history of Kawasaki disease (KD) is still unknown. METHODS: Using a permanent registry system in Japan (koseki), 6,576 persons with a history of KD were followed up. The average follow-up period was 30 years. The endpoint was death. RESULTS: With a 99.5% follow-up rate, 68 deaths (48 males and 20 females) were observed. The overall standardized mortality ratio, of which reference was vital statistics in Japan, was not elevated. However, the observation according to the presence or absence of cardiac sequelae showed that the standardized mortality ratio for those with cardiac sequelae significantly elevated. Nine persons, all of whom were males, died of KD (including those cases where KD was suspected), but all deaths occurred in individuals who were under 30 years of age. CONCLUSIONS: This study revealed the long-term prognosis for KD, but almost all participants were younger than 40 years. Continuing follow up of this cohort is required to clarify whether a history of KD relates to the development of atherosclerosis when participants become middle aged or older.

Serum alanine aminotransferase level and intravenous immunoglobulin resistance in patients with kawasaki disease.

INTRODUCTION/OBJECTIVES: Serum alanine aminotransferase (ALT) elevation is considered a risk factor for resistance to initial intravenous immunoglobulin (IVIG) treatment in patients with Kawasaki disease (KD). However, serum ALT levels change dramatically during acute KD illness. We tested the hypothesis that risk assessment for initial IVIG resistance based on serum ALT elevation may differ by examination day after KD onset. METHODS: We analyzed 18,492 population-based patients who developed KD throughout Japan. First, we epidemiologically evaluated the serum ALT variation at 1‒10 days after disease onset. Second, we conducted multivariable logistic regression to determine the association between serum ALT level and initial IVIG resistance according to timing of initial hospital visit by stratifying the patients into an early group (1‒5 days after onset) and a late group (6‒10 days after onset). RESULTS: Serum ALT rapidly increased after KD onset, peaked at day 4 of illness, and then declined regardless of IVIG responsiveness. The adjusted odds ratio (OR) increased with increasing serum ALT in the early group (adjusted OR [95% CI]: 1.44 [1.25-1.66], 1.94 [1.65-2.28], and 2.22 [1.99-2.48] for serum ALT 50-99, 100-199, and ≥ 200 IU/L, respectively; reference ALT level: 1-49 IU/L). No significant association was observed in the late group. CONCLUSIONS: The findings indicate that risk assessment for initial IVIG resistance based on serum ALT level may only be reliable for patients with KD who visit hospitals during early illness, specifically 1-5 days after disease onset. Key Points Serum alanine aminotransferase level differed markedly according to examination days after Kawasaki disease onset. Serum alanine aminotransferase level declined toward normal range after day 5 of illness regardless of intravenous immunoglobulin responsiveness. Elevated serum alanine aminotransferase level was no longer a significant risk factor for initial intravenous immunoglobulin resistance when measured on delayed hospital visits. Risk assessment for initial intravenous immunoglobulin resistance based on serum alanine aminotransferase level may only be reliable for patients who visit hospitals during early illness, specifically 1-5 days after disease onset.

Serum sodium level associated with coronary artery lesions in patients with Kawasaki disease.

INTRODUCTION/OBJECTIVES: Hyponatremia is a potential risk factor for the development of coronary artery lesions (CALs) identified after acute Kawasaki disease (KD). However, the serum sodium distribution corresponding to the reference intervals differs between infants (< 1 year of age) and older children. We hypothesized the association of serum sodium level with CAL complications differs between infants and older patients with KD. METHODS: We analyzed 21,610 population-based patients who developed KD throughout Japan during 2013-2014. We performed multivariable logistic regression analyses to evaluate the association between serum sodium and CAL complications. Additionally, we stratified the serum sodium distribution associated with CAL complications by infants and older patients. RESULTS: CALs were identified in 158 (3.6%) infants and 302 (1.8%) older patients. Infants were more likely to develop CALs when within the normal sodium range compared with older patients (75% vs. 29%), whereas most older patients developed CALs with a sodium level lower than the reference interval. Serum sodium ≤ 130 mEq/L indicated significantly higher risk for development of CALs in both groups (adjusted odds ratio [95% confidence intervals] = 3.21 [1.65-6.25] in infants and 1.74 [1.18-2.57] in older patients). CONCLUSIONS: Serum sodium distribution associated with CAL complications differed greatly between infants and older patients. Older patients developed CALs with sodium levels lower than the reference interval; however, among infants, hyponatremia was not necessarily a risk factor for developing coronary artery lesion. When considering risk assessments for CALs using serum sodium levels, infants with KD should be distinguished from older patients. Key Points • Hyponatremia is a potential risk factor for the development of coronary artery lesions (CALs) among patients with Kawasaki disease. • However, the serum sodium distribution corresponding to the reference intervals differs between infants (< 1 year of age) and older children. • Most infants developed CALs within the normal sodium range, whereas older patients developed at a range lower than the reference interval. • These findings highlight that when considering risk assessments for CALs using serum sodium levels, infants should be distinguished from older patients.

A nationwide questionnaire survey on the prevalence of ankylosing spondylitis and non-radiographic axial spondyloarthritis in Japan.

OBJECTIVE: This nationwide study aimed to reveal the prevalence of ankylosing spondylitis (AS), non-radiographic axial spondyloarthritis (nr-ax SpA), and the positivity rate of human leukocyte antigen (HLA) among such patients in Japan. METHODS: The first survey was conducted in 2221 randomly selected facilities (26.3%) in September 2018, where the patients with AS/nr-ax SpA were taken care of from January to December 2017. We estimated the total number of these patients using response and extraction rates. A second survey was conducted in 117 facilities (49.8%) to assess for HLA-B27 positivity rate and clinical features. RESULTS: The estimated total numbers of the patients with AS and nr-ax SpA were 3200 (95% confidence interval [CI]: 2400-3900) and 800 (530-1100), suggesting that the prevalence values of AS and nr-ax SpA in general population were 2.6/100,000 (0.0026%) and 0.6/100,000 (0.0006%), respectively. Although 55.5% (76/137) of patients with AS were HLA-B27-positive, those whose age of onset was estimated to be over 50 years tended to undergo less HLA-B27 testing. CONCLUSION: This study revealed the lower prevalence of AS/nr-ax SpA in Japan, compared to those in other countries. Further studies are required to reveal the association of HLA-B27 with the clinical features.

Clinical Characteristics of Patients With Kawasaki Disease Whose Siblings Had the Same Disease.

BACKGROUND: Some patients with Kawasaki disease (KD) have siblings who developed the same disease. Using a large-scale epidemiologic dataset, the present study aimed to determine the clinical characteristics of this population. METHODS: We analyzed 89,725 patients diagnosed with KD during 2011-2018 who were registered in the nationwide Japanese KD survey database. Multivariable logistic regression analyses were performed to determine factors associated with sibling history of KD. RESULTS: Of the 89,725 patients, 1777 (2%) had sibling history of KD. Annual prevalence ranged from 1.5% to 2.3% during the study period and showed a tendency toward an increasing trend. Patients with recurrent KD and parental history of KD were significantly associated with sibling history of KD (adjusted odds ratio [95% confidence interval] = 2.15 [1.82-2.54] and 2.64 [2.02-3.47], respectively). Although patients with a sibling history of KD were significantly associated with initial intravenous immunoglobulin treatment resistance (1.14 [1.02-1.28]), no significant association was found between sibling history and coronary artery abnormality development. Among patients with a sibling history of KD, male patients were less likely to have recurrent KD than female patients (0.68 [0.49-0.96]). CONCLUSIONS: The significant association between sibling history and parental history may indicate genetic susceptibility to KD onset. Among those with a sibling history, recurrent KD was more likely to occur in female patients. Further studies focusing on this population may contribute toward identification of the cause of KD onset.

Kawasaki Disease With Coronary Artery Lesions Detected at Initial Echocardiography.

Background Detection of coronary artery lesions (CALs) at initial echocardiography can aid in diagnosing Kawasaki disease (KD) and inform primary adjunctive treatments. We aimed to characterize patients with KD with CALs detected at initial echocardiography. Methods and Results We analyzed data from the nationwide Japanese KD survey that contained information on 103 222 population-based patients diagnosed with KD across Japan during 2011 to 2018. Patients with CALs detected at initial echocardiography were assessed by age, day of illness, and number of principal KD signs (≥3). Multivariable logistic regression analysis was performed to evaluate factors independently associated with CAL detection. Overall, 3707 (3.6%) patients had CALs detected at initial echocardiography. Patients aged <12 and ≥60 months were associated with CAL detection (adjusted odds ratio [95% CI], 1.28 [1.18‒1.39] and 1.32 [1.20‒1.45], respectively; reference, 12‒59 months). Patients with delayed hospital visits were increasingly at higher risk for CAL detection (days 7‒8, 1.84 [1.63‒2.08]; days 9-10, 4.30 [3.58-5.15]; and days ≥11, 9.12 [7.63‒10.90]; reference, days 1-4). Patients with 3 or 4 principal KD signs were independently associated with CAL detection (1.75 [1.63‒1.88]). These patients were significantly more likely to be aged <12 months but were not associated with delayed hospital visit. Younger patients visited at earlier days of illness. Conclusions Timely diagnosis could be beneficial for patients with KD. However, even when the hospital visit occurred early in the course of illness, patients with 3 or 4 principal KD signs, especially younger patients, were at higher risk of CAL detection at initial echocardiography.

Epidemiology and Risk Factors for Giant Coronary Artery Aneurysms Identified After Acute Kawasaki Disease.

A giant coronary artery (CA) aneurysm is a potentially fatal cardiac complication resulting from Kawasaki disease (KD). We aimed to identify epidemiologic characteristics and potential risk factors associated with giant CA aneurysms identified after acute KD. We analyzed 90,252 patients diagnosed with KD from 2011 to 2018, using data obtained in nationwide KD surveys conducted in Japan. Multivariable logistic regression analyses were performed to evaluate potential risk factors associated with subsequent giant CA aneurysm complications (defined as lumen size ≥ 8 mm), adjusting for all potential factors. Giant CA aneurysms were identified in 144 patients (0.16%) after acute KD. The annual prevalence ranged from 0.07 to 0.20% during the study period. In the multivariate analyses, male sex (adjusted odds ratio 2.09 [95% confidence interval 1.41-3.11], recurrent KD (1.90 [1.09-3.33]), IVIG administration at 1-4 days of illness (1.49 [1.04-2.15]) and ≥ 8 days after KD onset (2.52 [1.38-4.60]; reference, 5-7 days), detection of CA dilatations and aneurysms at initial echocardiography (4.17 [1.85-5.41] and 46.5 [28.8-74.8], respectively), and resistance to IVIG treatment (6.09 [4.23-8.75]) were significantly associated with giant CA aneurysm complications identified after acute KD. The annual prevalence of giant CA aneurysms identified after acute KD did not increase during the study period. Patients with larger CA abnormalities detected at initial echocardiography were independently associated with progression to giant CA aneurysm complications after acute KD regardless of the number of days from onset at treatment initiation.

Bacille Calmette-Guérin inoculation site changes and cardiac complications in patients with Kawasaki disease.

OBJECTIVE: To investigate whether redness and crusting at the bacille Calmette-Guérin inoculation site (BCGitis), identified during acute illness owing to Kawasaki disease (KD), is an independent risk factor for development of cardiac complications. DESIGN: Retrospective cohort study using data from the nationwide KD survey in Japan. SETTING: Survey respondents included hospitals specialising in paediatrics and hospitals with ≥100 beds and a paediatric department throughout Japan. PATIENTS: We included 17 181 patients with KD across Japan during 2005-2006. MAIN OUTCOME MEASURES: BCGitis and cardiac complications resulting from KD. RESULTS: BCGitis was identified in 7549 (44%) patients with KD. Compared with patients without BCGitis, those with BCGitis were younger, more likely to be male, less likely to have recurrent status and visited a hospital and underwent initial intravenous immunoglobulin (IVIG) treatment earlier after KD onset. In the unadjusted model, patients with BCGitis were significantly less likely to have cardiac complications (crude OR 0.81, 95% CI 0.71 to 0.92). However, after including treatment factors (days of illness at initial IVIG and treatment responsiveness) in the adjusted model, the association was no longer significant (adjusted OR 0.89, 95% CI 0.77 to 1.03), indicating that BCGitis was not an independent factor associated with cardiac complication and might be confounded by treatment factors. CONCLUSIONS: BCGitis was identified in comparatively early illness stages of KD. Our findings indicated that BCGitis was not an independent factor associated with developing cardiac complications but was confounded by prompt initial IVIG administration, which might result in successful treatment and prevention of cardiac complications.

Corticosteroids Added to Initial Intravenous Immunoglobulin Treatment for the Prevention of Coronary Artery Abnormalities in High-Risk Patients With Kawasaki Disease.

BACKGROUND Randomized controlled trials previously provided different conclusions about the superiority of adding corticosteroids to initial intravenous immunoglobulin treatment for the prevention of coronary artery abnormalities in patients with Kawasaki disease (KD). To further assess this issue, we analyzed large-scale data from nationwide KD surveys in Japan, where combination treatment (corticosteroids added to initial standard intravenous immunoglobulin treatment) has become commonly used for patients at high risk for KD. METHODS AND RESULTS Standard intravenous immunoglobulin treatment and combination treatment were compared using data from time periods with and without combination treatment. Outcome measures were coronary artery abnormalities and initial intravenous immunoglobulin treatment failure. Hospitals where ≥20% of patients received combination treatment were identified, and treatment and control groups were selected via matching by age, sex, illness day at initial treatment, and KD recurrence. Matched group selection and subsequent analyses were conducted 1000 times to minimize sampling bias and potential confounders (bootstrapping). From 115 hospitals, 1593 patients with KD in the treatment group and 1593 controls were selected for each of the 1000 sample iterations. The median proportion of patients who developed coronary artery abnormalities among the treatment group and controls were 4.6% (95% CI, 3.8%-5.8%) and 8.8% (95% CI, 7.5%-10.0%), respectively: an estimated risk ratio of 0.53 (0.41-0.67). A median of 14.1% (95% CI, 12.4%-15.9%) of the patients in the treatment group and 21.7% (95% CI, 19.8%-23.4%) in the controls had treatment failure: an estimated risk ratio of 0.65 (0.56-0.75). CONCLUSIONS Combination treatment reduced coronary artery abnormality risk by an estimated 47% and treatment failure by 35%. Multiple-dose corticosteroids may provide benefit in selected patients at high risk for KD.

Outcomes in Kawasaki disease patients with coronary artery abnormalities at admission.

BACKGROUND: Previous studies demonstrated that coronary artery lesions (CALs) resulting from Kawasaki disease (KD) can improve over time. However, limited information is available on sub-acute outcomes of CALs detected at admission during KD illness. METHODS: The nationwide Japanese KD survey contained substantial information on KD patients with CALs detected at admission and who received standard IVIG treatment within 10 days of disease onset. Coronary outcomes were evaluated by changes in CALs from admission to the first assessment at 30 days from disease onset in three categories: improved, unchanged, and progressed. Ordinal logistic regression analysis was performed to evaluate factors associated with the outcomes. RESULTS: Of 2024 patients with CALs detected at admission, improved, unchanged, and progressed outcomes were found in 1548 (76.5%), 390 (19.3%), and 86 (4.2%), respectively. Over 80% of patients with coronary artery (CA) dilatations had improved outcome. Independent factors associated with worse outcomes were larger-size CALs (adjusted ORs [95% CIs]: CA aneurysm = 5.13 [3.65-7.22] and giant CA aneurysms = 7.49 [3.56-15.72] compared with CA dilatation, respectively), age ≥ 60 months (1.45 [1.08-1.94] compared with 12-59 months), recurrent KD (1.57 [1.07-2.29]), parental history of KD (2.23 [1.02-4.85]), and delayed admission (8-10 days from disease onset: 1.76 [1.21-2.57] compared with 1-4 days). CONCLUSIONS: KD patients with larger CALs, ≥60 months old, and with recurrent status or parental history may require more rigorous treatment. In addition, delayed admission may result in worse coronary outcome, indicating that prompt diagnosis and treatment are required.

Epidemiology, Treatments, and Cardiac Complications in Patients with Kawasaki Disease: The Nationwide Survey in Japan, 2017-2018.

OBJECTIVE: To report the epidemiologic characteristics, treatments, and cardiac complications of Kawasaki disease, using data from the nationwide survey in Japan. STUDY DESIGN: The nationwide Kawasaki disease survey in Japan has been conducted biennially since 1970. The most recent survey was completed in 2019, obtaining information for patients who developed Kawasaki disease during 2017-2018. Survey respondents were hospitals specializing in pediatrics and those with ≥100 beds and a pediatric department throughout Japan, where patients with Kawasaki disease were eventually hospitalized. RESULTS: The survey identified 32 528 patients with Kawasaki disease, which consisted of 15 164 (46.6%) in 2017 and 17 364 (53.4%) in 2018. The highest annual incidence rate was recorded in 2018 (359 per 100 000 children aged 0-4 years). After 1982, patients with ≤4 principal Kawasaki disease signs gradually increased, resulting in 6847 (21.1%) patients diagnosed during 2017-2018. Among the 30 784 patients receiving initial intravenous immunoglobulin administration, 6061 (19.7%) did not respond. Within 30 days of Kawasaki disease onset, 9.0% of patients were diagnosed with cardiac complications, and 2.6% of patients developed cardiac sequelae after the acute illness. CONCLUSIONS: The annual number of patients developing Kawasaki disease in Japan increased from 1970 through 2018, whereas the proportion of patients with Kawasaki disease with cardiac complications decreased in the most recent 2 decades. Early diagnosis of Kawasaki disease as well as advances in initial treatments could explain these findings.

Cumulative incidence of Kawasaki disease with cardiac sequelae in Japan.

BACKGROUND: Some patients with Kawasaki disease (KD) develop cardiac sequelae, which increase the risk of subsequent ischemic heart events. Knowing the cumulative incidence (CI) of KD with cardiac sequelae may contribute to developing health policies to prevent subsequent ischemic events in these patients. METHODS: Study participants consisted of 254 984 patients aged 0-9 years with KD who were registered in nationwide surveys in Japan from 1991-2016. We calculated the incidence probabilities by dividing the number of patients with KD aged 0-9 years by the population used in vital statistics of each calendar year. We calculated the cumulative proportion of those not affected by KD, by multiplying each probability in patients aged from age 0-9 years. The CI of KD was obtained by subtracting this value from 1. We also calculated the number of patients in each birth cohort (BC). The same was done to calculate the CI of KD-related cardiac sequelae. RESULTS: The CIBC steadily increased from 0.005067 in males and 0.003668 in females in 1991 to 0.011431 in males and 0.0088253 in females in 2007. The CIBC of KD with cardiac sequelae decreased from 0.000478 in males and 0.000213 in females in 1997 to 0.000339 in males and 0.000169 in females in 2007. CONCLUSION: The increasing CIBC of KD indicates an increased susceptibility to KD in accordance with birth year. The decreasing CIBC of cardiac sequelae suggests the efficacy of KD treatment.

Platelet Count Variation and Risk for Coronary Artery Abnormalities in Kawasaki Disease.

BACKGROUND: Platelet count is considered as a biomarker for the development of coronary artery abnormalities (CAAs) among Kawasaki disease (KD) patients. However, previous studies have reported inconsistent results. We addressed the controversial association of platelet count with CAAs using a large-scale dataset. METHODS: A retrospective cohort study was conducted using KD survey data from Japan (2015-2016; n = 25,448). Classifying patients by intravenous immunoglobulin (IVIG) responsiveness, we described the trends in platelet count using the lowest and highest values along with the specific illness days. Multivariate logistic regression analysis was performed to evaluate the association between platelet count and CAAs, adjusting for relevant factors. RESULTS: Platelet counts rapidly decreased from admission, reached the lowest count at 6-7 days, and peaked after 10 days. Platelet counts in IVIG non-responders decreased with a lower minimum value than IVIG responders, but subsequently rebounded toward a higher maximum. Compared with patients with normal platelet counts (150-450 × 10/L), patients with abnormally high platelet counts (>450 × 10/L) were more likely to have CAAs at admission (adjusted odds ratio: IVIG responders, 1.50 [95% confidence interval 1.20-1.87] and non-responders, 1.46 [1.01-2.12]). By contrast, IVIG non-responding patients whose counts were below normal (<150 × 10/L) after hospitalization were at higher risk for developing CAAs (2.27 [1.44-3.58]). CONCLUSIONS: Platelet count varied widely by illness day and was confounded by IVIG responsiveness, which might have contributed to previous inconsistent findings. KD patients with abnormally high platelet counts at admission or abnormally low counts after hospitalization were at higher risk for CAAs.

Clinical background factors affecting outcomes of Helicobacter pylori eradication therapy in primary care.

OBJECTIVE: Few studies have reported the influence of clinical background factors on the outcome of Helicobacter pylori eradication therapy in primary care practice. We aimed to determine which clinical background factors influence the outcome of eradication therapy in a primary care setting. METHODS: This was a retrospective study of patients who received H pylori eradication therapy at Higashiohmi City Gamo Medical Center, Shiga, Japan, from January 2012 to December 2015. We investigated clinical background factors associated with success, failure, and self-interruption of H pylori eradication therapy: patients' age, gender, first- or second-line treatment, reasons for receiving gastroenterological endoscopic examination, method of drug administration, and attending physicians' age and their specialties. RESULTS: There were 369 patients (208 females, 161 male), with a mean age of 59 years (range 30-88 years). The middle-aged group (50-69 years) was associated with successful eradication therapy compared with the young group (30-49 years). The elderly group (>70 years) was associated with eradication therapy failure compared with the middle-aged group. The young group was associated with self-interruption of eradication therapy. There was a marginally significant association between male patients and self-interruption. Older attending physicians (>50 years) were also associated with failure compared with younger physicians. There was no difference in outcome of eradication therapy between generalists and gastroenterology specialists. CONCLUSION: We have identified clinical factors associated with success, failure, and self-interruption of H pylori eradication therapy in a primary care setting.

Seasonality of i.v. immunoglobulin responsiveness in Kawasaki disease.

BACKGROUND: Evidence suggests that seasonal variation in the onset of Kawasaki disease (KD) exists worldwide. Whether a seasonal component to successful i.v. immunoglobulin (IVIG) therapy exists in KD-positive children, however, is unknown. We addressed this question by focusing on patients with primary onset KD who were non-responsive to IVIG treatment, in the large nationwide Japanese KD survey datasets from 2009 to 2016. METHODS: In these datasets, the IVIG therapy non-responders were defined as patients whose fever persisted ≥24 h or recurred ≤24 h after the end of the initial IVIG treatment (dosage, 2,000 mg/kg). Those who successfully responded to this treatment were defined as IVIG responders. The consecutive monthly trend of the proportion of IVIG non-responders was analyzed throughout the study period to investigate seasonal periodicity on Fourier analysis, and the monthly distributions of non-responders and responders were compared. RESULTS: From a total of 113 691 KD-positive patients, 15.7% were IVIG non-responders, and 61% were male. The proportion of non-responders increased across each calendar year with fluctuation, and Fourier analysis indicated seasonal periodicity. The seasonality effect differed between responders and non-responders, with the proportion of responders tending to increase in autumn through winter, while the non-responders showed a decreasing trend in autumn. The seasonality effect tended to differ by sex. CONCLUSIONS: The results indicate that the currently unknown etiological agents of KD might differ between IVIG responders and non-responders. In addition, immune reactivity against such agents possibly differs by sex in the IVIG non-responders.