Prospective monitoring of Epstein-Barr virus and other herpesviruses in patients with juvenile idiopathic arthritis treated with methotrexate and tocilizumab

The Impact of Epstein-Barr Virus Infection on Juvenile Idiopathic Arthritis Activity and Patient's Response to Treatment

This study aimed to investigate the relationship between Epstein-Barr virus (EBV) infection and the onset of juvenile idiopathic arthritis (JIA), disease activity, and response to treatment. The study included 44 children with JIA, 23 children with different types of arthritis, and 44 controls. We measured EBV infection markers, including the EBV DNA load and the concentration of antibodies to viral antigens, at disease onset, before treatment. Six months after JIA diagnosis and the initiation of treatment patients with anti-viral capsid antigen IgG had a higher disease activity and worse response to treatment than patients without previous infection. After six months of treatment, the probability of disease inactivity in children without a history of EBV infection was almost 6.5 times greater than in a child with a history of infection. Furthermore, the probability of a better response after six months of treatment in a child with a history of EBV infection was more than five times smaller than in a child without infection. A past EBV infection can have a negative effect on achieving disease remission and may be associated with a worse response to treatment. Our results do not indicate the need for routine assessment of EBV infection markers in patients with JIA.

Clinical management for other iatrogenic immunodeficiency-associated lymphoproliferative disorders

Other iatrogenic immunodeficiency-associated lymphoproliferative disorders (OIIA-LPD), a category of immunodeficiency-associated LPD according to the World Health Organization classification, is associated with immunosuppressive drugs (ISDs). Several factors, including autoimmune disease (AID) activity, Epstein-Barr virus (EBV) infection, ISD usage, and aging, influence the development of OIIA-LPD, resulting in complicated clinical courses and outcomes. Most OIIA-LPD develops in patients with rheumatoid arthritis using methotrexate (MTX-LPD). The management of MTX-LPD is based on the clinical course, i.e., with/without regression, with/without relapse/regrowth event (RRE), LPD subtype, and ISDs for AIDs after LPD development. There are three clinical courses after ISD withdrawal: regressive LPD without relapse/regrowth (R-G), regressive LPD with RRE (R/R-G), and persistent LPD (P-G). The majority of EBV+ diffuse large B-cell lymphomas are classified in R-G, whereas classic Hodgkin lymphoma is generally classified in R/R-G. Polymorphic LPD (P-LPD) in MTX-LPD develops with heterogeneous pathological features similar to monomorphic LPD. Chemotherapy for MTX-LPD is selected according to that for de novo LPD, although the strategy for aggressive P-LPD and non-specific LPD is not well established. The absolute lymphocyte count in the peripheral blood has been suggested as a candidate marker for MTX-LPD development and RRE. Several clinical issues, including correct diagnosis among overlapping clinicopathological features in MTX-LPD and clinical management of LPD by ISDs other than MTX, require further investigation.

Diagnosis and management of infectious complications of childhood rheumatic diseases

Progress in the diagnosis and management of pediatric rheumatic disease has improved complications from underlying disease and the survival of children. However, as a consequence, infection has now become one of the leading causes of morbidity and mortality. Differentiating between infections and disease flares in children with rheumatic conditions can often pose diagnostic quandaries. Children with rheumatic diseases are at risk of infection, not only because of the use of immune-modulating medications but also because of underlying immune dysfunction associated with their disease. Although bacterial infections are the most common, any organism can potentially be a causative agent and, at times, more invasive measures of diagnosis, for example bronchoscopy and tissue biopsies may be necessary. Maintaining a high index of suspicion of infection with prompt diagnosis and treatment are important to further improve patient outcomes.