Elevated levels of interleukin 6 in serum of patients with serious group A streptococcal infections

Levels of proinflammatory cytokines in plasma after pneumoccoccal immunization in human immunodeficiency virus type 1-infected patients

To ascertain if immunization with pneumococcal polysaccharide vaccine is associated with rises in the levels of proinflammatory cytokines in the plasma of human immunodeficiency virus type 1 (HIV-1)-infected patients, the levels of tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) were measured serially after immunization. IL-6 levels rose an average of 2.2- and 2.1-fold 6 and 8 h after immunization, respectively, but TNF-alpha levels remained unchanged. The levels of these cytokines were stable in unimmunized controls. Immunization with pneumococcal polysaccharide vaccine induces increases in the levels of IL-6 in the plasma of persons with HIV-1 infection.

Dynamics of blood cytokine concentrations in patients with bacteremic infections

Cytokines play a major role in the pathophysiology of sepsis and septic shock. Using enzyme immunoassays the acute serum levels of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), granulocyte-colony stimulating factor (G-CSF), interleukin-8 (IL-8), and leukemia inhibitory factor (LIF) were investigated in 90 patients with positive blood cultures and clinical signs of infection. In 27 patients samples were obtained on admission, after 1, 4, 12, 18, and 24 h, and then daily. The acute serum levels of IL-6, TNF-alpha, G-CSF, and IL-8 were significantly higher among patients with severe sepsis. Patients with Gram-negative infection had significantly higher levels of TNF-alpha on admission than did patients with Gram-positive infections (p = 0.0008). The levels of IL-6, G-CSF and, to some extent, TNF-alpha decreased rapidly in survivors within the first 24 h of admission to hospital and institution of treatment. LIF was detected in 8/90 in both survivors and nonsurvivors.

Correlation between serum TNF alpha and IL6 levels and severity of group A streptococcal infections

The multiorgan failure syndrome caused by group A streptococci (GAS) designated streptococcal toxic shock syndrome (STSS) is believed to be mediated by cytokines induced by superantigens. In order to study the relationship between superantigen production, cytokine levels in patient sera, and clinical GAS manifestation we examined acute-phase sera and strains from 25 patients with GAS bacteremia. The patients had various disease manifestations, including STSS (44%), erysipelas (28%), septicemia (24%), wound infections (16%), and pneumonia (12%). Serotype T1M1 dominated, representing 56% of the isolates, but also strains of other serotypes were identified. The strains were found to produce the streptococcal pyrogenic exotoxins (Spe) A, B, and F, as determined by immuno-blot analyses. There was no difference in amounts of toxin produced between strains isolated from patients with different manifestations of disease. Levels of TNF alpha, IL1 alpha, IL6, IL8, and IFN gamma in acute-phase sera were determined by use of ELISA and RIA assays. The analyses showed higher levels of IL6 in sera from patients with STSS than in sera from patients with bacteremia without shock. TNF alpha was elevated in sera from patients with STSS, as compared to sera from patients with uncomplicated pharyngotonsillitis. No increase in the levels of IL1 alpha, IL8, and IFN gamma could be found in the patient sera and there was no difference in the level of those cytokines between the various patient categories.