First-line corticosteroids for Kawasaki disease: Pulse versus multiple dose.

BACKGROUND: Kawasaki disease (KD) can result in severe coronary artery abnormalities (CAAs). Corticosteroids added to initial standard intravenous immunoglobulin (IVIG) treatment may decrease the risk for these complications. Different corticosteroid regimens (single-day high dose pulse vs multiple lower doses) may contribute to the discrepant results of prior studies. METHODS: Using data from the 22nd, 23rd , and 24th Japanese nationwide KD surveys (2011-2016), we identified KD patients who did not have CAAs at first presentation and who were treated with either pulse or multiple-dose corticosteroids as part of their initial treatment. Occurrence of subsequent CAAs and treatment failure were compared between the treatment regimens and adjusted odds ratios were calculated controlling for sex, age group, illness day at first treatment, survey, and recurrent KD. RESULTS: There were 782 KD patients who received pulse corticosteroid treatment and 4,817 who received multiple dose treatment. Patients receiving multiple dose treatment were less likely to develop CAAs (5.5% vs 8.3%, OR 0.64; 95% CI: 0.48-0.85) or treatment failure (21.4% vs 41.6%; OR: 0.38; 95% CI: 0.33-0.45). Adjusted analyses showed similar protective effects of multiple-dose treatment against CAAs (OR: 0.67, 95% CI: 0.51-0.90) and treatment failure (OR: 0.39, 95% CI: 0.33-0.46). CONCLUSIONS: Multiple-dose corticosteroid combination treatment resulted in substantially improved outcomes in KD patients compared to pulse treatment. For patients who may be at elevated risk of treatment failure or CAA, use of multiple-dose corticosteroids in conjunction with IVIG is likely to provide considerable clinical benefit.

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.

Cardiac Complications, Earlier Treatment, and Initial Disease Severity in Kawasaki Disease.

OBJECTIVES: To assess if observed higher observed risks of cardiac complications for patients with Kawasaki disease (KD) treated earlier may reflect bias due to confounding from initial disease severity, as opposed to any negative effect of earlier treatment. STUDY DESIGN: We used data from Japanese nationwide KD surveys from 1997 to 2004. Receipt of additional intravenous immunoglobulin (IVIG) (data available all years) or any additional treatment (available for 2003-2004) were assessed as proxies for initial disease severity. We determined associations between earlier or later IVIG treatment (defined as receipt of IVIG on days 1-4 vs days 5-10 of illness) and cardiac complications by stratifying by receipt of additional treatment or by using logistic modeling to control for the effect of receiving additional treatment. RESULTS: A total of 48 310 patients with KD were included in the analysis. In unadjusted analysis, earlier IVIG treatment was associated with a higher risk for 4 categories of cardiac complications, including all major cardiac complications (risk ratio, 1.10; 95% CI, 1.06-1.15). Stratifying by receipt of additional treatment removed this association, and earlier IVIG treatment became protective against all major cardiac complications when controlling for any additional treatment in logistic regressions (OR, 0.90; 95% CI, 0.80-1.00). CONCLUSIONS: Observed higher risks of cardiac complications among patients with KD receiving IVIG treatment on days 1-4 of the illness are most likely due to underlying higher initial disease severity, and patients with KD should continue to be treated with IVIG as early as possible.

Intracranial Procedures and Expected Frequency of Creutzfeldt-Jakob Disease.

BACKGROUND/AIMS: To assess the frequency and characteristics of intracranial procedures (ICPs) performed and the number of U.S. residents living with a history of ICP. These data are used to calculate the expected annual number of sporadic Creutzfeldt-Jakob disease (CJD) cases among U.S. residents with a history of ICP. METHODS: The Nationwide Inpatient Sample provided data on the frequency and types of ICPs, and data from the National Center for Health Statistics was used to produce age-adjusted mortality rates. A model was constructed, which estimated long-term survival and sporadic CJD rates among ICP patients based on procedure type and age. RESULTS: There were an estimated 2,070,488 ICPs in the United States from 1998 to 2007, an average of over 200,000 per year. There were an estimated 2,023,726 U.S. residents in 2013 with a history of ICP in the previous 30 years. In 2013, there was expected to be 4.1 sporadic CJD cases (95% CI 1-8) among people with a history of ICP in the past 30 years. CONCLUSIONS: The considerable proportion of U.S. residents living with a history of ICP is important information for retrospective assessments of CJD or any other suspected long-term outcome of ICPs.

Recent US Case of Variant Creutzfeldt-Jakob Disease-Global Implications.

Variant Creutzfeldt-Jakob disease (vCJD) is a rare, fatal prion disease resulting from transmission to humans of the infectious agent of bovine spongiform encephalopathy. We describe the clinical presentation of a recent case of vCJD in the United States and provide an update on diagnostic testing. The location of this patient's exposure is less clear than those in the 3 previously reported US cases, but strong evidence indicates that exposure to contaminated beef occurred outside the United States more than a decade before illness onset. This case exemplifies the persistent risk for vCJD acquired in unsuspected geographic locations and highlights the need for continued global surveillance and awareness to prevent further dissemination of vCJD.

Recurrent Kawasaki disease: USA and Japan.

BACKGROUND: Descriptive epidemiologic studies of recurrent and non-recurrent Kawasaki disease (KD) may identify other potentially important differences between these illnesses. METHODS: Data from the USA and Japan, the Centers for Disease Control and Prevention (CDC) national KD surveillance(1984-2008) and the 17th Japanese nationwide survey (2001-2002), respectively, were analyzed to examine recurrent KD patients <18 years of age meeting the CDC KD case or atypical KD case definition. These patients were compared with non-recurrent KD patients. RESULTS: Of the 5557 US KD patients <18 years of age during 1984-2008, 97 (1.7%) were identified as having had recurrent KD. Among the US Asian/Pacific Islander KD patients, 3.5% had recurrent KD, which was similar to the percentage identified among KD patients (3.5%) in the Japanese survey. Compared with non-recurrent KD patients, KD patients [with recurrent KD] were more likely to be older, fulfill the atypical KD case definition, and have coronary artery abnormalities (CAA) despite i.v. immunoglobulin (IVIG) treatment. CONCLUSIONS: Differences in the age, race, and frequency of CAA exist between recurrent and non-recurrent KD patients. The increased association of CAA with recurrent KD suggests that more aggressive treatment strategies in conjunction with IVIG may be indicated for the second episode of KD.

Suicides in National Hormone Pituitary Program Recipients of Cadaver-Derived Human Growth Hormone.

Context: Numerous reports of suicide among individuals who received cadaver-derived human growth hormone (c-hGH) through the National Hormone Pituitary Program (NHPP) raised the alarm for potentially increased suicide risk. Objective: We conducted a study to assess suicide risk in the NHPP cohort and identify contributing factors to facilitate early recognition and intervention. Methods: The study population consisted of patients receiving NHPP c-hGH starting from 1957, and cohort deaths with an ICD code consistent with suicide or possible suicide through 2020 were evaluated. Descriptive data were extracted from medical records. Standardized mortality ratios (SMRs) to compare the observed number of suicide deaths in the cohort to the expected number were calculated using general population suicide rates by sex, age group, and time period. Results: Among 6272 patients there were 1200 all-cause cohort deaths, of which 55 (52 male, 3 female) were attributed to suicide. Of these, 47 were identified by ICD code alone compared to an expected count of 37.8 (SMR = 1.25, 95% CI 0.91-1.66). Among male cohort members, the SMR was 1.33 (95% CI 0.97-1.78). Elevated risk of suicide was detected for cohort members aged 25-34 (SMR = 1.79, 95% CI 1.06-2.83) and during the period from September 19, 1985, to December 31, 1998 (SMR = 1.70, 95% CI 1.02-2.65). Conclusion: Overall, the observed number of suicides among NHPP c-hGH recipients was not significantly higher than expected. However, certain subgroups may be at elevated risk of suicide. Studies are needed to better understand the nature and magnitude of suicide risk among c-hGH recipients to facilitate early intervention to prevent suicide deaths.

Neurological diagnoses in hospitalized COVID-19 patients during the B.1.1.529 surge.

OBJECTIVE: Emerging variants and sublineages of SARS-CoV-2 have differing disease severity, transmissibility, and immune evasion. The neurological conditions associated with the original strain of SARS-CoV-2 are well established. Our study assessed the neurological presentations specific to hospitalized patients during the B.1.1.529 (Omicron) variant surge in New York City. METHODS: A total of 178 cases with positive RT-PCR result within 6 weeks before admission, and subsequent development of select neurological conditions during the SARS-CoV-2 B.1.1.529 (Omicron) surge between December 1, 2021 and February 28, 2022, were included from 12,800 SARS-CoV-2-positive hospital admissions. Clinical data from acute hospitalizations were compared to findings of inpatient neurological cases with COVID-19 infections from the initial surge in NYC in the same hospital system. RESULTS: Compared to SARS-CoV-2 infections of the original strain, COVID-19 cases hospitalized during the Omicron surge (B.1.1.529) were associated with incidental and/or asymptomatic COVID-19 cases (96, 53.9%) and an increased incidence of pre-existing neurological and immunocompromising conditions. Encephalopathy, seizures, and stroke remained the most prevalent neurological conditions identified in hospitalized COVID-19 cases during the study period, reflecting a similar distribution of neurological presentations associated with the original strain. INTERPRETATION: In our cohort of 178 admitted SARS-CoV-2-positive patients with select neurological conditions during the Omicron B.1.1.529 surge, 54% of COVID-19 cases were considered incidental and/or asymptomatic, and the identified neurological conditions resembled those associated with the original SARS-CoV-2 strain. Further studies characterizing neurological presentation in Omicron sublineages and other variants are warranted in an ongoing COVID-19 pandemic.

Sporadic fatal insomnia in a young woman: a diagnostic challenge: case report.

BACKGROUND: Sporadic fatal insomnia (sFI) and fatal familial insomnia (FFI) are rare human prion diseases. CASE PRESENTATION: We report a case of a 33-year-old female who died of a prion disease for whom the diagnosis of sFI or FFI was not considered clinically. Following death of this patient, an interview with a close family member indicated the patient's illness included a major change in her sleep pattern, corroborating the reported autopsy diagnosis of sFI. Genetic tests identified no prion protein (PrP) gene mutation, but neuropathological examination and molecular study showed protease-resistant PrP (PrPres) in several brain regions and severe atrophy of the anterior-ventral and medial-dorsal thalamic nuclei similar to that described in FFI. CONCLUSIONS: In patients with suspected prion disease, a characteristic change in sleep pattern can be an important clinical clue for identifying sFI or FFI; polysomnography (PSG), genetic analysis, and nuclear imaging may aid in diagnosis.

Toxic Shock Syndrome in Patients Younger than 21 Years of Age, United States, 2006-2018.

We examined the incidence of toxic shock syndrome in the United States during 2006-2018 among persons <21 years old with commercial or Medicaid-insurance using administrative data. There were 1008 commercially-insured and 481 Medicaid-insured toxic shock syndrome cases. The annual rate was 1 per 100,000 and stable over time. Rates were even lower in children <5 years old and stable over time.

Sporadic Creutzfeldt-Jakob Disease in a Very Young Person.

BACKGROUND AND OBJECTIVES: Sporadic Creutzfeldt-Jakob disease (sCJD) is the most common form of human prion disease and typically occurs in middle to late life. sCJD in early adulthood is extremely uncommon. The purpose of this report is to raise awareness of cases of sCJD in young patients that are not associated with a genetic mutation or acquired prion disease risk factors. METHODS: We describe the clinical presentation, diagnostic workup, and postmortem examination of a 22-year-old man with sCJD. RESULTS: The patient presented with a rapidly progressive neurocognitive disorder consisting of early and prominent psychiatric symptoms. CSF real-time quaking-induced conversion (RT-QuIC) was indeterminate, and brain MRI was suggestive of prion disease. Neuropathologic examination and the absence of a genetic mutation and acquired prion disease risk factors resulted in a final diagnosis of sCJD. CONCLUSION: Although extremely rare, sCJD can occur in young people and should be considered in the setting of rapidly progressive neuropsychiatric conditions. Postmortem examination is required to diagnose the type of prion disease and remains important to surveil for known and potentially novel acquired prion diseases.

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.

Kawasaki Disease and Kawasaki Disease Shock Syndrome Hospitalization Rates in the United States, 2006-2018.

BACKGROUND: Kawasaki disease (KD) is a febrile illness of unknown etiology. Patients with Kawasaki disease shock syndrome (KDSS) may present with clinical signs of poor perfusion and systolic hypotension in addition to typical KD features. The United States Centers for Disease Control and Prevention analyzes and interprets large hospitalization databases as a mechanism for conducting national KD surveillance. METHODS: The Kids' Inpatient Database (KID), the National (Nationwide) Inpatient Sample (NIS), and the IBM MarketScan Commercial (MSC) and MarketScan Medicaid (MSM) databases were analyzed to determine KD-associated hospitalization rates and trends from 2006 to the most recent year of available data. KD and potential KDSS hospitalizations were defined using International Classification of Disease-Clinical Modification codes. RESULTS: For the most recent year, the KD-associated hospitalization rates for children <5 years of age were 19.8 (95% CI: 17.2-22.3, KID: 2016), 19.6 (95% CI: 16.8-22.4, NIS: 2017), 19.3 (MSC: 2018), and 18.4 (MSM: 2018) per 100,000. There was no indication of an increase in KD rates over the time period. Rates of potential KDSS among children <18 years of age, ranging from 0.0 to 0.7 per 100,000, increased; coding indicated potential KDSS for approximately 2.8%-5.3% of KD hospitalizations. CONCLUSIONS: Analyses of these large, national databases produced consistent KD-associated hospitalization rates, with no increase over time detected; however, the percentage of KD hospitalizations with potential KDSS increased. Given reports of increasing incidence elsewhere and the recent identification of a novel virus-associated syndrome with possible Kawasaki-like features, continued national surveillance is important to detect changes in disease epidemiology.

Prion disease incidence in the United States: 2003-2015.

OBJECTIVE: To report the incidence of prion disease in the United States. METHODS: Prion disease decedents were retrospectively identified from the US national multiple cause-of-death data for 2003-2015 and matched with decedents in the National Prion Disease Pathology Surveillance Center (NPDPSC) database through comparison of demographic variables. NPDPSC decedents with neuropathologic or genetic test results positive for prion disease for whom no match was found in the multiple cause-of-death data were added as cases for incidence calculations; those with cause-of-death data indicating prion disease but with negative neuropathology results were removed. Age-specific and age-adjusted average annual incidence rates were then calculated. RESULTS: A total of 5,212 decedents were identified as having prion disease, for an age-adjusted average annual incidence of 1.2 cases per million population (range 1.0 per million [2004 and 2006] to 1.4 per million [2013]). The median age at death was 67 years. Ten decedents were <30 years of age (average annual incidence of 6.2 per billion); only 2 of these very young cases were sporadic forms of prion disease. Average annual incidence among those ≥65 years of age was 5.9 per million. CONCLUSIONS: Prion disease incidence can be estimated by augmenting mortality data with the results of neuropathologic and genetic testing. Cases <30 years of age were extremely rare, and most could be attributed to exogenous factors or the presence of a genetic mutation. Continued vigilance for prion diseases in all age groups remains prudent.

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.

Human Prion Disease Surveillance in Washington State, 2006-2017.

Importance: Human prion disease surveillance is critical to detect possible cases of variant Creutzfeldt-Jakob disease and other acquired forms of prion disease in the United States. Results are presented here that describe 12 years of surveillance in Washington, the only US state that has reported the presence of classic bovine spongiform encephalopathy, an animal prion disease that has been shown to transmit to humans. Objective: To describe the current prion disease surveillance system in Washington and the epidemiological and clinical results of surveillance from 2006 through 2017. Design, Setting, and Participants: This cross-sectional study reports findings from the human prion disease surveillance system in place in Washington state from January 1, 2006, through December 31, 2017. Participants included Washington residents with a clinical suspicion of human prion disease or suggestive test results from the National Prion Disease Pathology Surveillance Center or with prion disease listed as a cause of death on the death certificate. Data for this report were analyzed from June 1, 2016, to July 1, 2020. Exposure: Human prion disease diagnosis. Main Outcomes and Measures: The main outcome was incidence of human prion disease cases, including identification of variant Creutzfeldt-Jakob disease. Results: A total of 143 human prion disease cases were detected during the study period, none of which met criteria for a variant Creutzfeldt-Jakob disease diagnosis. Among 137 definite or probable cases, 123 (89.8%) occurred in persons aged 55 years or older, with a median age at death of 66 years (range, 38-84 years). Most patients were White (124 [92.5%] among 134 with reported race), and slightly over half were male (70 [51.1%]). The average annual age-adjusted prion disease incidence was 1.5 per million population per year, slightly higher than the national rate of 1.2 per million. A total of 99 cases (69.2%) were confirmed by neuropathology. Sporadic prion disease was the most common diagnosis, in 134 cases (93.7%), followed by familial prion disease in 8 cases (5.6%). One iatrogenic prion disease case (0.7%) was also reported. Conclusions and Relevance: The findings of this cross-sectional study suggest that demographic characteristics of patients with prion disease in Washington are consistent with national findings. The slightly higher incidence rate may be due to the state's enhanced surveillance activities, including close collaboration with key partners and educational efforts targeted toward health care providers. Results indicate that surveillance will continue to be beneficial for monitoring epidemiological trends, facilitating accurate diagnoses, and detecting variant Creutzfeldt-Jakob disease or other emerging human prion disease cases.

Diagnosis of prion diseases by RT-QuIC results in improved surveillance.

OBJECTIVE: To present the National Prion Disease Pathology Surveillance Center's (NPDPSC's) experience using CSF real-time quaking-induced conversion (RT-QuIC) as a diagnostic test, to examine factors associated with false-negative RT-QuIC results, and to investigate the impact of RT-QuICs on prion disease surveillance. METHODS: Between May 2015 and April 2018, the NPDPSC received 10,498 CSF specimens that were included in the study. Sensitivity and specificity analyses were performed on 567 autopsy-verified cases. Prion disease type, demographic characteristics, specimen color, and time variables were examined for association with RT-QuIC results. The effect of including positive RT-QuIC cases in prion disease surveillance was examined. RESULTS: The diagnostic sensitivity and specificity of RT-QuIC across all prion diseases were 90.3% and 98.5%, respectively. Diagnostic sensitivity was lower for fatal familial insomnia, Gerstmann-Sträussler-Scheinker disease, sporadic fatal insomnia, variably protease sensitive prionopathy, and the VV1 and MM2 subtypes of sporadic Creutzfeldt-Jakob disease. Individuals with prion disease and negative RT-QuIC results were younger and had lower tau levels and nonelevated 14-3-3 levels compared to RT-QuIC-positive cases. Sensitivity was high throughout the disease course. Some cases that initially tested RT-QuIC negative had a subsequent specimen test positive. Including positive RT-QuIC cases in surveillance statistics increased laboratory-based case ascertainment of prion disease by 90% over autopsy alone. CONCLUSIONS: RT-QuIC has high sensitivity and specificity for diagnosing prion diseases. Sensitivity limitations are associated with prion disease type, age, and related CSF diagnostic results. RT-QuIC greatly improves laboratory-based prion disease ascertainment for surveillance purposes. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that second-generation RT-QuIC identifies prion disease with a sensitivity of 90.3% and specificity of 98.5% among patients being screened for these diseases due to concerning symptoms.

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.

Analysis of potential risk factors associated with nonresponse to initial intravenous immunoglobulin treatment among Kawasaki disease patients in Japan.

BACKGROUND: Some Kawasaki disease (KD) patients do not respond to initial treatment with intravenous immunoglobulin (IVIG). The purpose of this study was to determine potential risk factors associated with IVIG nonresponse among KD patients in Japan. METHODS: Data were obtained from questionnaires used for the 18th nationwide KD survey of patients who visited hospitals in Japan from 2003 through 2004. Data for patients who met the case definition for KD and received 2 g/kg single infusion IVIG as the initial treatment within 10 days of illness were analyzed. IVIG nonresponders were defined as patients who needed secondary treatment after initial IVIG administration. RESULTS: Among 15,940 KD patients in Japan during 2003-2004, 6330 patients received 2 g/kg single infusion IVIG within 10 days of illness onset. IVIG nonresponders accounted for 20.3% of them (n = 1286). Male sex [odds ratio (OR), 1.21, 95% confidence interval (CI), 1.06-1.37], receipt of the initial IVIG before the fifth day of illness (OR: 1.89, 95% CI: 1.66-2.15), and having recurrent KD (OR: 1.38, 95% CI: 1.00-1.90) were significantly associated with IVIG nonresponse. In addition, IVIG nonresponders had significantly higher risks for coronary artery aneurysms (OR: 10.38, 95% CI: 6.98-15.45) or giant coronary artery aneurysms (OR: 54.06, 95% CI: 12.84-227.65). CONCLUSIONS: Physicians should consider potential IVIG nonresponse among recurrent KD patients or KD patients diagnosed and treated before the fifth day of illness, particularly if they are boys and have laboratory values associated with nonresponse such as low platelet count, and elevated alanine aminotransferase and C-reactive protein. Some of these patients may benefit from administration of the alternative secondary treatment early during the illness along with the initial IVIG treatment.