Ayelen Xicohtencatl Muñoz

Background/Objectives: Lyme disease is a tick-borne zoonosis caused by Borrelia burgdorferi that can affect multiple organ systems. Although cardiovascular involvement is considered uncommon, it may lead to severe and potentially life-threatening complications, particularly conduction disturbances and inflammatory cardiac conditions. This review aims to describe the spectrum of cardiovascular manifestations documented in patients with Lyme disease, focusing on clinical presentation, diagnostic approaches, management strategies, and reported outcomes. Methods: A narrative literature review was performed using PubMed, MEDLINE, and Google Scholar. Articles published between January 2000 and July 2025 in English or Spanish were screened. Eligible studies included original research articles, systematic and narrative reviews, case series, and case reports describing confirmed Lyme disease with cardiovascular involvement. A total of 30 studies were included. The available evidence was predominantly based on case reports and small case series, with considerable heterogeneity in study design, patient populations, and reported outcomes. Data on clinical manifestations, diagnostic methods, treatment strategies, and outcomes were extracted and synthesized. Results: Atrioventricular conduction disturbances were the most frequently reported cardiovascular manifestation, ranging from first-degree block to complete heart block, often presenting abruptly with syncope or bradycardia. Other reported manifestations included atrial and ventricular arrhythmias, myocarditis, pericarditis, myopericarditis, valvular endocarditis, aortitis, and vasculitis. Diagnosis relied on a combination of clinical suspicion, epidemiologic exposure, serologic testing, electrocardiographic monitoring, and cardiac imaging. Most patients were treated with antimicrobial therapy, commonly intravenous ceftriaxone followed by oral doxycycline, with temporary pacemaker support required in selected cases. Overall, clinical outcomes were favorable when treatment was initiated promptly. Conclusions: Cardiovascular involvement in Lyme disease, although infrequent, encompasses a broad clinical spectrum with potentially serious consequences. Early recognition, appropriate diagnostic evaluation, and timely antimicrobial therapy are essential to ensure reversibility of cardiac manifestations and favorable outcomes. However, the available evidence is limited by heterogeneity and the predominance of low-level-evidence studies.

Colorectal cancer (CRC) is one of the leading causes of mortality worldwide, with rising cases in individuals under 50 years old, classified as early-onset CRC (EO-CRC). EO-CRC is characterized by having clinical features related to a worse prognosis and outcome. This underscores the critical need for early detection biomarkers. ncRNAs emerge as potential biomarkers for diagnosis, prognosis, and treatment response in other types of cancers. Sequencing data from the NCBI Bioproject PRJNA787417 were analyzed to identify differentially expressed miRNAs in early- and late-onset colorectal cancer (EO-CRC and LO-CRC). Differential expressions were assessed with a log fold change threshold of 1 and an adjusted p-value of 0.05. Predicted mRNA targets were identified via ENCORI and analyzed for pathway enrichment using the SHINYGO algorithm. RNA-seq analysis identified a 25-ncRNA EO-CRC signature, including hsa-miR-195 (downregulated) and hsa-miR-549a (upregulated), with enrichment analyses suggesting associations with MAPK, PI3K, VEGF, and KRAS pathways commonly linked to angiogenesis, migration, and invasion. This preliminary report highlights a 25-gene deregulated signature in EO-CRC, in which hsa-miR-195 and hsa-miR-549a emerge as biomarkers of clinical relevance, regulating key genes involved in angiogenesis, migration, and invasion. Their dysregulation could contribute to the aggressive clinical features and poor outcomes observed in EO-CRC.