Novel Highly Divergent SARS-CoV-2 Lineage With the Spike Substitutions L249S and E484K.

COVID-19 pandemics has led to genetic diversification of SARS-CoV-2 and the appearance of variants with potential impact in transmissibility and viral escape from acquired immunity. We report a new and highly divergent lineage containing 21 distinctive mutations (10 non-synonymous, eight synonymous, and three substitutions in non-coding regions). The amino acid changes L249S and E484K located at the CTD and RBD of the Spike protein could be of special interest due to their potential biological role in the virus-host relationship. Further studies are required for monitoring the epidemiologic impact of this new lineage.

Genomic Epidemiology of Severe Acute Respiratory Syndrome Coronavirus 2, Colombia.

Coronavirus disease (COVID-19) in Colombia was first diagnosed in a traveler arriving from Italy on February 26, 2020. However, limited data are available on the origins and number of introductions of COVID-19 into the country. We sequenced the causative agent of COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), from 43 clinical samples we collected, along with another 79 genome sequences available from Colombia. We investigated the emergence and importation routes for SARS-CoV-2 into Colombia by using epidemiologic, historical air travel, and phylogenetic observations. Our study provides evidence of multiple introductions, mostly from Europe, and documents >12 lineages. Phylogenetic findings validate the lineage diversity, support multiple importation events, and demonstrate the evolutionary relationship of epidemiologically linked transmission chains. Our results reconstruct the early evolutionary history of SARS-CoV-2 in Colombia and highlight the advantages of genome sequencing to complement COVID-19 outbreak investigations.

Spindle cell oncocytoma of the adenohypophysis.

Spindle cell oncocytoma of the adenohypophysis (SCO) is defined as spindle to epithelioid cells with oncocytic appearance presenting in the adenohypophysis. In contrast to pituitary adenomas, the SCO does not show immunoreactivity for neuroendocrine markers and pituitary hormones but co-expressed vimentin, S-100 protein, epithelial membrane antigen (EMA), and antimitochondrial antibody MU213-UC clone 131-1. We describe an SCO in an adult, a 42-year-old woman whose magnetic resonance (MR) images documented an intrasellar lesion located in the hypophysis. Histopathological examination showed a tumor composed predominantly of spindle cells. Immunohistochemical studies showed positivity for vimentin, S10, EMA, and antimitochondrial antibody MU213-UC clone 131. Cytokeratin (CK) (AE1/AE3), glial fibrillary acidic protein (GFAP), chromogranin, synaptophysin, PGP9.5, CD57, desmin, D2-40, smooth muscle actin (SMA), Bcl-2, progesterone receptor, and CD34 were negative. Neuropeptides were negative. With electron microscopy, the neoplastic cells appear filled with mitochondria, well-formed desmosomes, but lacked secretory granules. SPO is a rare non-endocrine neoplasm of the adenohypophysis with benign biological behavior corresponding to WHO grade I.

Tumor neuroectodérmico primitivo primario vesical: estudio hispatológico e inmunohistoquímico. Reporte de un caso / A Histopathological and Immunohistochemical Case Study of a Primary Primitive Neuroectodermal Bladder Tumor

El tumor neuroectodérmico primitivo primario vesical es una entidad infrecuente que se presenta en pacientes que superan los 50 años de edad. Se trata de una enfermedad regional avanzada, altamente maligna, de crecimiento rápido y, en la mayoría de los casos, letal. Para hacer su diagnóstico se requiere descartar otras neoplasias; por lo tanto, es necesario implementar técnicas de inmunohistoquímica y estudios de citogenética. El artículo reporta el caso de un paciente remitido al Instituto Nacional de Cancerología. Los estudios histopatológicos revelaron la presencia de un tumor neuroectodérmico primario vesical y descartaron diagnósticos diferenciales con un carcinoma y un linfoma vesical. Los resultados de inmunohistoquímica confirmaron el origen neuroectodérmico del tumor y descartaron neoplasias epiteliales y hematolinfoides, que tienen mayor frecuencia de presentación vesical. La evolución clínica concuerda con lo referido en la literatura de desenlaces fatales en periodos cortos.

A primary primitive neuroectodermal bladder tumor, which occurs among patients over 50, is not common. It is an extremely malignant, advanced regional disease that spreads rapidly and is usually lethal. Diagnosis requires ruling out other neoplasms; thus making immunohistochemical and cytogenetic studies indispensable. We report on a case treated at the National Cancer Institute of Colombia. Histopathological studies revealed the presence of a primary primitive neuroectodermal bladder tumor and ruled out differential diagnosis of carcinoma and bladder lymphoma. The immunohistochemical results confirmed neuroectodermal tumor origin and ruled out epitelial neoplasms and hematolymphoids which frequently occur in the bladder. The clinical evolution coincides with that of the literature on short term fatal outcomes.