Search

Background: High levels of infliximab (IFX) directed antibodies (IFX-Ab) may result in significant reduction in IFX concentration and loss of drug efficacy., Objectives: To assess the input of measuring serum IFX levels and levels of IFX-Ab in the management of rheumatic diseases., Methods: Serum levels of IFX and anti-IFX-Ab were measured by ELISA (IFX-Abs were also identified by anti-human lambda chain Ab) and correlated to patients (responders and nonresponders) disease activity scores., Results: A total of 144 tests for IFX were performed in 91 patients (mean age 50.2 years and disease duration 9.9 years). Among responders (57 patients) levels (mean, median) of IFX were significantly higher than in non-responders (34 patients) (4.2 mcg/ml (2.3) versus 1.1 mcg/ml (0.45)); levels of IFX-Ab in responders were significantly lower than in non-responders (4.59 mcg/ml (1.0) versus 13.1 (6.1)). High IFX-Ab levels predicted IFX discontinuation in 8.8% of responders and 55.9% among non-responders. In non-responders with low IFX levels and low IFX-Ab, the shortening of re-treatment intervals lead to significant improvement. In about 28% of patients, results of blood tests influenced treatment decisions., Conclusions: Assessment of immunogenicity of anti-TNF monoclonal antibodies proved useful information for guiding the therapy in rheumatic diseases with suboptimal clinical response. Patients with low IFX levels and low levels of IFXAb may benefit from increasing the drug dose or decreasing of re-treatment intervals. In patients with negligible serum levels of IFX and high levels of IFX-Ab, the therapy should be switched to another biological agent, probably with a different mechanism of action.

Introduction: Timolol eye-drops are commonly used for the treatment of glaucoma. Despite being topically applied, some systemic absorption occurs with the resulting adverse reactions related to its beta-adrenoreceptor blocking activity, Case Presentation: We report the case of a 68 years old healthy male who was admitted to our department for further workup following two episodes of syncope. Medical history taking revealed that the episodes of syncope occurred soon after beginning treatment with intra-ocular timolol for glaucoma. An electrocardiogram demonstrated a sinus bradycardia rhythm and a prolonged PR interval, consistent with the negative effects of a beta adrenergic receptor antagonist on the heart's electrical generation and conduction system., Discussion: This case demonstrates the potential for dangerous systemic side effects of a topically-applied medication. It also highlights the importance of thorough medical history taking in the evaluation of syncope, including inquiry regarding the use of all, especially new, medications., Conclusion: Detailed medical history taking can help in avoiding the performance of an expensive and unnecessary workup.