287. Characteristics of Pediatric ANCA Associated Vasculitis among Racial/Ethnic Minorities- single center experience from United States

Background: ANCA-associated vasculitides (AAV) are rare systemic diseases that generally manifest in adulthood and include granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Adult studies have demonstrated severe disease and higher damage indices in Hispanics in comparison to Caucasians. There is limited information about the characteristics of AAV in children from racial and ethnic minority groups in the United States. The objective of this study was to study the characteristics of AAV among racial/ethnic minorities in comparison to white children in Central California, United States.

Methods: We performed a retrospective case review of patients less than 18 years of age diagnosed with AAV at a tertiary care children’s hospital in Central California in United States from January 1, 2010 to March 31, 2021. Cases were identified from electronic health records using ICD-9 and ICD-10 codes for vasculitis. Records were reviewed for a diagnosis of AAV based on ACR/EULAR classification criteria. Demographic and clinical data including laboratory parameters, treatment, and outcomes were collected. Continuous data were expressed as a median and interquartile range, categorical data as frequency and percentages. Chi-square and Mann-Whitney U tests were used for statistical comparison as appropriate.

Results: Twenty-one cases of pediatric AAV were identified. Overall, 43% were white (n=9), 57% were racial/ethnic minority including Hispanics (9), Asians (2), and other/mixed race (1). The median age at diagnosis was 13 years (IQR 10.4-15.3) in the racial/ethnic minority group, compared to 15.6 years (IQR 14-16.7) in the white cohort (Table 1). 92% were female in the racial/ethnic minority cohort meanwhile, among white patients, 44% were female (p=0.05).  The racial/ethnic minority group had higher myeloperoxidase (MPO) positivity (77% versus 11%, p <0.01) meanwhile white patients had a significantly higher frequency of proteinase 3 (PR3) positivity (66.7% versus 16.7%, p <0.01). Trends towards longer length of hospital stay (20 days versus 15 days, p=0.2), higher rates of plasmapheresis (33% versus 11%; p=0.3), requirement for dialysis (50% versus 33%, p=0.7), and higher rates of ICU admission (58% versus 44 %, p =0.7) were noted in racial/ethnic minorities, although it did not reach statistical significance. All patients received treatment with high-dose steroids at diagnosis. Immunosuppressive therapy included cyclophosphamide (42% in racial/ethnic minority cohort and 78% in white cohort), rituximab (33% in racial/ethnic minority cohort and 11% in white cohort), cyclophosphamide and rituximab (17% in racial/ethnic minority cohort and 11% in white cohort). There were no deaths in the white cohort, but 17% mortality (n=2) was reported in the racial/ethnic minority cohort. Causes of death were Aspergillus pneumonia and pulmonary hemorrhage.

Conclusions: Our study compares the characteristics of AAV among children from racial/ethnic minority and white groups in the Central California of United States. We observed more frequent MPO positivity in racial/ethnic minority children. Racial/ethnic minority children with AAV required ICU admission, plasmapheresis, and dialysis more frequently than white children. Racial/ethnic minorities had a longer length of hospital stay and death was more frequently noted. Limitations of our study include its small sample size. This study highlights the need for further research to understand the impact of race/ethnicity on pediatric AAV presentation, disease activity, and outcomes.

Disclosures: None