Responses to Treatment According to the Cytokine Profiles of Pericardial Effusion in Two Children with Idiopathic Pericarditis.

Acute pericarditis is inflammation of the pericardium with or without pericardial effusion. In the pediatric population, most patients with acute pericarditis are diagnosed with idiopathic pericarditis. Herein, we present two children with idiopathic pericarditis who underwent immunological assessment of pericardial effusion for the first time. Both patients showed equally high levels of interleukin-6 in the pericardial effusion. However, they had different treatment responses, in accordance with the pericardial effusion and serum interleukin-10 concentrations. Our present cases suggest that interleukin-10 may be associated with the response to anti-inflammatory therapy in idiopathic acute pericarditis.

Correlation of natural autoantibodies and cardiovascular disease-related anti-bacterial antibodies in pericardial fluid of cardiac surgery patients.

Our previous studies showed that anti-citrate synthase (anti-CS) immunoglobulin (Ig)M natural autoantibodies are present in healthy individuals without previous antigen stimulation, but no studies have investigated their presence in the pericardial fluid (PF). Therefore, we detected the natural anti-CS IgG/M autoantibody levels in plasma and PF of cardiac surgery patients and investigated their relationship with cardiovascular disease-associated bacterial pathogens. PF and blood samples of 22 coronary artery bypass graft (CABG) and 10 aortic valve replacement (AVR) patients were tested for total Ig levels, natural autoantibodies and infection-related antibodies using enzyme-linked immunosorbent assay (ELISA) and Luminex methods. The B cell subsets were measured by flow cytometry. The total Ig subclass levels were four to eight times lower in PF than in plasma, but the natural anti-CS IgM autoantibodies showed a relative increase in PF. The frequency of CD19+ B lymphocytes was significantly lower in PF than in blood (P = 0·01), with a significant relative increase of B1 cells (P = 0·005). Mycoplasma pneumoniae antibody-positive patients had significantly higher anti-CS IgM levels. In CABG patients we found a correlation between anti-CS IgG levels and M. pneumoniae, Chlamydia pneumoniae and Borrelia burgdorferi antibody titres. Our results provide the first evidence that natural autoantibodies are present in the PF, and they show a significant correlation with certain anti-bacterial antibody titres in a disease-specific manner.

IgG4-related disease manifesting as pericarditis with elevated adenosine deaminase and IL-10 levels in pericardial fluid.

A 78-year-old female with massive pericardial effusion fulfilled diagnostic criteria for immunoglobulin G4 (IgG4)-related disease. Although her adenosine deaminase (ADA) level in the pericardial effusion was high, all the tests for tuberculosis infection were negative. Immunostaining of the pericardium biopsy specimen revealed remarkably increased IgG4-positive cells. This is the first report describing IgG4-related pericarditis with elevated ADA level. We also demonstrate the elevated interleukin-10 (IL-10) level in pericardial fluid and IL-10-producing T-cells in the pericardium.