Response to: ‘Drug-induced lupus erythematosus following immunotherapy with anti-programmed death-(ligand) 1’ by Michot et al and ‘Checkpoint inhibitor-associated immune arthritis’ by Arnaud et al

Gut Barrier Damage and Gut Translocation of Pathogen Molecules in Lupus, an Impact of Innate Immunity (Macrophages and Neutrophils) in Autoimmune Disease

The gut barrier is a single cell layer that separates gut micro-organisms from the host, and gut permeability defects result in the translocation of microbial molecules from the gut into the blood. Despite the silent clinical manifestation, gut translocation of microbial molecules can induce systemic inflammation that might be an endogenous exacerbating factor of systemic lupus erythematosus. In contrast, circulatory immune-complex deposition and the effect of medications on the gut, an organ with an extremely large surface area, of patients with active lupus might cause gut translocation of microbial molecules, which worsens lupus severity. Likewise, the imbalance of gut microbiota may initiate lupus and/or interfere with gut integrity which results in microbial translocation and lupus exacerbation. Moreover, immune hyper-responsiveness of innate immune cells (macrophages and neutrophils) is demonstrated in a lupus model from the loss of inhibitory Fc gamma receptor IIb (FcgRIIb), which induces prominent responses through the cross-link between activating-FcgRs and innate immune receptors. The immune hyper-responsiveness can cause cell death, especially apoptosis and neutrophil extracellular traps (NETosis), which possibly exacerbates lupus, partly through the enhanced exposure of the self-antigens. Leaky gut monitoring and treatments (such as probiotics) might be beneficial in lupus. Here, we discuss the current information on leaky gut in lupus.

New patterns of cutaneous drug eruptions

Cutaneous adverse drug reactions produce a significant clinical, financial, and psychological burden on our healthcare industry. The importance of considering a drug reaction in the cause of any dermatitis is underscored by the diversity of clinical manifestations and the prolific rate of drug discovery and approval. We present an update on the variety of drug reactions encountered in the inpatient and outpatient setting. Immunomodulatory drugs used in oncology will be reviewed separately as their clinical manifestations cross many reaction patters and morphologies.