Mimicry of Rhabdomyosarcoma by Tonsillar Actinomycosis: Case Report.

Actinomycosis is a rare infectious disease characterized by slowly progressive, chronic suppurative lesions, often mistaken for malignancies due to its ability to mimic them. It is caused by Actinomyces bacteria, which are part of the normal flora of the human oropharynx, gastrointestinal, and urogenital tracts. This case report describes a 51-year-old male with a history of mandibular rhabdomyosarcoma presenting with severe shoulder and hip pain, dysphagia, and headaches, initially suspected to be a cancer recurrence. However, after further investigation, including a PET-CT and tonsillectomy, the diagnosis of actinomycosis was confirmed through histopathological examination. The case highlights the diagnostic challenges of actinomycosis, especially in patients with complex clinical histories, emphasizing the importance of considering it as a differential diagnosis in similar presentations. The patient was treated with long-term antibiotic therapy, predominantly beta-lactams, demonstrating the necessity of a comprehensive diagnostic approach and the implications of a delayed diagnosis. This case underscores the critical need for high clinical suspicion and awareness among healthcare professionals regarding the potential for actinomycosis to mimic more common diseases, ensuring timely and accurate treatment.

Reasons for antiretroviral switching in Colombia: A retrospective cohort study.

INTRODUCTION: Long-term use of antiretroviral therapy (ART) for HIV infection might lead to the necessity of switching regimens. We aimed to analyze the reasons for the ART switch, the time-to-switch of ART, and its associated factors in a Colombian cohort. METHODS: We conducted a retrospective cohort in 20 HIV clinics, including participants ≥18 years old with confirmed HIV infection who underwent an ART switch from January 2017 to December 2019 with at least 6 months of follow-up. A time-to-event analysis and an exploratory Cox model were performed. RESULTS: 796 participants switched ART during the study period. The leading cause of ART switch was drug intolerance (n = 449; 56.4%) with a median time-to-switch of 12.2 months. The longest median time-to-switch was due to regimen simplification (42.4 months). People ≥50 years old (HR = 0.6; 95% CI (0.5-0.7) and CDC stage 3 at diagnosis (HR = 0.8; 95% CI (0.6-0.9) had less hazard for switching ART over time. CONCLUSIONS: In this Colombian cohort, drug intolerance was the main cause of the ART switch, and the time-to-switch is shorter than reports from other countries. In Colombia, it is crucial to apply current recommendations for ART initiation to choose regimens with a better tolerability profile.

Cytokine markers of B lymphocytes in minor salivary gland infiltrates in Sjögren's syndrome.

Sjögren's syndrome (SS) is a chronic autoimmune disorder characterised by the clinical presence of sicca syndrome. SS compromises the dysfunction of exocrine glands due to the presence of focal, mononuclear cell infiltrates that surround the ducts and replace the secretory units. Abnormal expression of different cytokines and chemokines such as B-cell activating factor, CXC Motif Chemokine Ligand 13, interleukin 6 (IL-6), IL-22, and FMS-like tyrosine kinase 3 ligand as well as that of their corresponding receptors has been implicated in the inflammatory process. The severity of glandular infiltration has been suggested to be associated with the presence of extra-glandular systemic manifestations, contributing to a clinical spectrum of the most severe disease. This review describes several cytokines and chemokines associated with B lymphocytes expressed in the minor salivary gland, their chemical structures, and their roles in SS as possible early predictors of lymphoma development and disease progression.