Publications by authors named "Ryuhei Ishihara"

The varicella-zoster virus (VZV) is a human neurotropic herpes virus responsible for varicella and herpes zoster (HZ). Following primary infection in childhood, VZV manifests as varicella (chickenpox) and enters a period of latency within the dorsal root ganglion. A compromised cellular immune response due to aging or immunosuppression triggers viral reactivation and the development of HZ (shingles).

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The global outbreak of coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus type 2 has prompted the rapid spread and development of vaccines to prevent the spread of the disease. COVID-19 vaccine has demonstrated excellent efficacy in reducing morbidity and severity of the disease, and most adverse reactions are very minor. However, some patients have been reported to develop autoimmune diseases, such as rheumatoid arthritis, myocarditis, Guillain-Barre syndrome, and vasculitis, following COVID-19 vaccination.

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Coronavirus disease 2019 (COVID-19) vaccines have been delivered worldwide to prevent the spread of the disease, and almost all Japanese have received the mRNA vaccines "BNT162b2" (Pfizer-BioNTech) or "mRNA-1273" (Moderna). These vaccines have shown efficacy and safety with only minor adverse drug reactions. However, some patients develop severe adverse drug reactions, including autoimmune reactions.

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The coronavirus disease (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 has led to rapid progress in vaccine development to prevent the spread of the disease. Although COVID-19 vaccines have excellent effectiveness in reducing morbidity and disease severity with minor adverse reactions, some patients develop late hypersensitivity events as autoimmune reactions such as rheumatoid arthritis, lupus nephritis, and vasculitis following COVID-19 vaccination. Herein, we describe a case of pneumonitis following COVID-19 mRNA vaccination in a patient with rheumatoid arthritis, which resolved spontaneously.

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Recently, treatment for rheumatoid arthritis has dramatically improved but increases the risk of bacterial and opportunistic infections. Herein, we report a fatal case of concurrent disseminated tuberculosis, pneumocystis pneumonia, and septic shock due to pyelonephritis caused by extended-spectrum -lactamase-producing in a patient with rheumatoid arthritis who received methotrexate, glucocorticoid, and tocilizumab. Despite undergoing intensive treatment, the patient developed respiratory failure and died after 7 days of admission.

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Objectives: This study aims to determine if obesity is a risk factor for a poor response to anti-tumor necrosis factor alpha (anti-TNFα) therapy in Japanese patients with rheumatoid arthritis (RA) using the appropriate body mass index (BMI) cut-off points for Asian populations.

Patients And Methods: This retrospective cohort study evaluated 382 outpatients with RA (98 males, 284 females; mean age 54.2 years; range, 18 to 84 years) who had received anti-TNFα therapy between May 2009 and July 2017.

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