Atopic dermatitis is a chronic inflammatory dermatosis characterized by pruritic, scaly, erythematous lesions. Its incidence varies but is estimated to be approximately 20% in children and between 7 and 14% in adults, with variation amongst countries. It is a multifactorial condition, with a complex interplay between genetic, immunological, and environmental factors. Research into the inflammatory response has identified new therapeutic targets that work to reduce inflammation and subsequently reduce flares. This study explores existing therapeutic agents for atopic dermatitis as well as newer therapies such as biologics and small molecules, drawing upon each agent’s mechanism of action, relevant landmark clinical trials, efficacy, and safety profile. Current therapies include emollients, corticosteroids, cyclosporine A, calcineurin inhibitors, phototherapy, and methotrexate. Biologics described include dupilumab, tralokinumab, lebrikizumab, nemolizumab, and rocatinlimab. Small molecules inhibitors include Janus kinase inhibitors, phosphodiesterase 4 inhibitors, transient receptor potential vanilloid subfamily V member 1 antagonist, and aryl hydrocarbon receptor antagonist.
Anticytokine autoantibodies (AAbs), particularly anti-interferon-gamma (anti-IFN-γ) AAbs, disrupt cytokine functions, leading to infections, autoimmune-like diseases, and conditions resembling interleukin-12 (IL-12)/IFN-γ pathway defects. Advances in genetic testing have clarified overlaps between autoinflammatory, autoimmune disorders, and primary immunodeficiencies but reveal complex phenotypes and pathways. While these insights deepen our understanding of immune mechanisms, they also complicate diagnosis and treatment, with limited options for IFN-γ deficiencies caused by genetic mutations. The adult-onset immunodeficiency with disseminated lymphadenitis due to nontuberculous mycobacteria (NTM) and other opportunistic infections has been linked to high levels of anti-IFN-γ AAbs. This syndrome, initially identified in HIV-negative Asian patients, frequently affects individuals of Asian descent and may be associated with specific human leukocyte antigen (HLA) alleles. The presence of neutralizing anti-IFN-γ AAbs impairs the IFN-γ-dependent immune response, likely contributing to the persistent NTM infection. This study underscores the potential for late-onset anti-IFN-γ AAb syndrome to manifest with disseminated NTM (dNTM) infections, highlights the importance of timely diagnosis and considers rituximab as a potential therapeutic option.
Syphilis is a sexually transmitted infection that is undergoing a resurgence in Canada and around the world. If not diagnosed correctly, syphilis can progress to its secondary and tertiary stages, affecting numerous organ systems. We present a case of a 41-year-old female who developed a papulosquamous rash, initially diagnosed as varicella with progression to a widespread and painful rash over 3 months. Based on clinical, histological, and serological findings, she was later diagnosed with secondary syphilis and successfully treated with intramuscular penicillin. This case underscores the importance of accurate diagnosis and treatment of syphilis to prevent systemic complications. We advocate for increased awareness among frontline providers with a proactive approach to diagnosis and management, including thorough history and physical examination, low threshold for performing serological testing, biopsy for lesions that do not resolve as expected with management, and multidisciplinary involvement for complex presentations of syphilis.