Childhood-Onset ANCA- Associated Vasculitis: single center experience from Central California.

BACKGROUND: Childhood-onset ANCA-associated vasculitides (AAV) are characterized by necrotizing inflammation and include granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Pediatric data is scare and there have been no prior studies examining the characteristics of pediatric AAV in Central California. METHODS: This retrospective study comprised AAV patients ≤18 years of age, diagnosed between 2010 and 2021, in Central California. We analyzed initial presentation including demographics, clinical, laboratory characteristics, treatment, and initial outcomes. RESULTS: Of 21 patients with AAV, 12 were categorized as MPA and 9 with GPA. Median age at diagnosis was 13.7 years in MPA cohort and 14 years in GPA. MPA cohort were majority females (92% versus 44%). 57% of the cohort were racial/ethnic minority including Hispanics (n = 9), Asians (n = 2), multiracial (n = 1) and 43% were white (n = 9). MPA patients were more frequently Hispanic (67%), meanwhile GPA patients were frequently white (78%). Median duration of symptoms prior to diagnosis was 14 days in MPA cohort and 21 days in GPA cohort. Renal involvement was frequent (100% in MPA and 78% in GPA). GPA cohort had frequent ear, nose and throat (ENT) involvement (89%). All patients were ANCA positive. All Hispanic patients were MPO positive, meanwhile 89% of white patients were PR3 positive. MPA cohort tended towards more severe disease with 67% requiring ICU admission and 50% requiring dialysis. Two deaths were reported in MPA cohort, related to Aspergillus pneumonia and pulmonary hemorrhage. In MPA cohort, 42% received cyclophosphamide in combination with steroids and 42% received rituximab in combination with steroids. GPA patients received cyclophosphamide, either with steroids alone (78%) or in combination with steroids and rituximab (22%). CONCLUSIONS: Microscopic polyangiitis was the most frequent AAV subtype with female preponderance, shorter duration of symptoms at onset and higher proportion of racial/ ethnic minority patients. Hispanic children demonstrated frequent MPO positivity. Trends towards higher rates of ICU requirement and need for dialysis upon initial presentation was noted in MPA. Patients with MPA received rituximab more frequently. Future prospective studies are needed to understand differences in presentation and outcomes in childhood onset AAV between diverse racial-ethnic groups.

Systemic Lupus Erythematosus Lymphadenopathy Presenting as Kikuchi-Fujimoto Disease in an Adolescent.

Systemic lupus erythematosus is a multisystem autoimmune disorder with a highly heterogeneous clinical presentation. The clinical phenotype varies from mild cutaneous and musculoskeletal manifestations to neurological involvement. Lymphadenopathy is a frequent manifestation of SLE, but the association is often not recognized, as lymphadenopathy is not a criterion for diagnosis. An unusual and seldom reported mimicker of lupus lymphadenitis is Kikuchi-Fujimoto Disease. This is a rare self-limiting disease of young adult females that presents with lymphadenopathy, fever, and systemic symptoms. Lupus lymphadenitis and KFD share some common clinical and pathologic features; but distinguishing between those two diseases can be challenging. We describe a 16-year-old Hispanic female who presented with axillary lymphadenopathy and was initially diagnosed with KFD based on an excisional lymph node biopsy; but later met the criteria for the 2019 European League Against Rheumatism/American College of Rheumatology classification criteria SLE. This case highlights the need for clinicians to be aware that patients with SLE may present with lymphadenopathy and to consider the association between Kikuchi disease and SLE to prevent misdiagnosis and allow for timely treatment to avoid complications.

Chikungunya Virus Disease: An Emerging Challenge for the Rheumatologist.

Chikungunya is caused by an alphavirus that is transmitted to humans via the Aedes species mosquito. Chikungunya is endemic to tropical Africa and South and Southeast Asia, but over the past decade, the geographic distribution of the virus has been expanding rapidly. The disease is characterized by fever and severe polyarthritis, and although symptoms typically resolve within 7 to 10 days, some patients experience persistent arthritis and arthralgias for months to years.In December 2013, the first local transmission of chikungunya virus in the Americas was identified in the Caribbean Island of Saint Martin. Since then, the number of afflicted individuals has spread throughout the Caribbean and Central America, as well as into South America. The United States reported 2788 chikungunya virus disease cases among travelers returning from affected areas in 2014. In addition, 11 locally acquired cases were reported in Florida. Further spread and establishment of the disease in the Americas are likely considering the high levels of viremia in infected individuals, widespread distribution of effective vectors, lack of immunity among people living in the Americas, and the popularity of international travel.Considering the prominent rheumatic manifestations of chikungunya, rheumatologists are likely to encounter patients with the disease in their practice. We recommend that rheumatologists consider chikungunya in their differential diagnosis when evaluating patients presenting with fever and joint pain following travel to a chikungunya endemic area. Early diagnosis would ensure timely management and reduction of polypharmacy and its associated complications. In this article, we briefly describe the epidemiology of chikungunya, the clinical features, laboratory testing, prevention, and treatment of disease.