Israel Medical Association Journal

Chronic Q fever, caused by Coxiella burnetii, is a persistent infection that primarily affects individuals with underlying valvular or vascular abnormalities. The standard treatment regimen consists of prolonged dual therapy with doxycycline and hydroxychloroquine, typically administered for a minimum of 18 months [1]. This combination targets both the intracellular pathogen and the acidic vacuolar environment in which it resides. A key indicator of therapeutic response is the progressive decline in phase I IgG antibody titers, which is generally observed within the first few months of treatment [2].

However, in rare instances, antibody titers may remain persistently elevated despite prolonged therapy, raising concerns about treatment failure, resistance, or host-related factors. The following case highlights an unusual drug interaction that interfered with treatment efficacy, ultimately preventing complete clinical resolution.

Thrombosis is a common phenomenon in patients with malignancies. It is believed that thrombosis is multifactorial and that in addition to mechanisms directly associated with cancer and its treatment, it may also be related to the interaction between the immune system and clotting. The present work describes four cancer patients (three adults and one child) whose clinical course was characteristic of catastrophic antiphospholipid syndrome (CAPS) in intensive care units of the National Cancer Institute of Rio de Janeiro. The presence of findings similar to those in CAPS can be attributed to an unbalanced interaction between the immune system and coagulation.

The DRESS syndrome (drug reaction with eosinophilia and systemic symptoms), also known as DIHS (drug-induced hypersensitivity syndrome), presents clinically as an extensive mucocutaneous rash, accompanied by fever, lymphadenopathy, hepatitis, hematologic abnormalities with eosinophilia and atypical lymphocytes, and may involve other organs with eosinophilic infiltration, producing damage in several systems, especially kidney, heart, lungs, and pancreas. The pathogenesis is related to specific drugs (especially the aromatic anticonvulsants), altered immune response, sequential reactivation of herpes virus, and association with some HLA alleles. Glucocorticoids are the basis for the treatment of the syndrome, which may be given with intravenous immunoglobulin and, in selected cases, ganciclovir. This article reviews current concepts regarding the interaction of drugs, viruses and immune responses during this complex adverse-drug reaction.
 

Knowledge on the pathophysiology of irritable bowel syndrome has evolved, beginning with disturbances in motility to visceral hypersensitivity, and ultimately to alterations in brain-gut bi­directional communication, where neurotransmitters such as serotonin play a key role. Recently, a multicomponent disease model that integrates all these alterations was proposed. This model is divided into physiological, cognitive, emotional and behavioral components that explain the gastrointestinal as well as the constitutional symptoms. In recent years there has been an explosion of research together with new developments in pharmacological treatments for lBS that support each compo­nent of this model. This review presents recent data in favor of these alterations in IBS.