Laboratory-based surveillance of Candida auris in Colombia, 2016-2020.

BACKGROUND: Since the first report of Candida auris in 2016, the Colombian Instituto Nacional de Salud (INS) has implemented a national surveillance of the emerging multidrug-resistant fungus. OBJECTIVES: This report summarises the findings of this laboratory-based surveillance from March 2016 to December 2020. RESULTS: A total of 1720 C. auris cases were identified, including 393 (23%) colonisation cases and 1327 (77%) clinical cases. Cases were reported in 20 of 32 (62%) departments of Colombia and involved hospitals from 33 cities. The median age of patients was 34 years; 317 (18%) cases were children under 16 years, 54% were male. The peak number of cases was observed in 2019 (n = 541). In 2020, 379 (94%) of 404 cases reported were clinical cases, including 225 bloodstream infections (BSI) and 154 non-BSI. Among the 404 cases reported in 2020, severe COVID-19 was reported in 122 (30%). Antifungal susceptibility was tested in 379 isolates. Using CDC tentative breakpoints for resistance, 35% of isolates were fluconazole resistant, 33% were amphotericin B resistant, and 0.3% isolates were anidulafungin resistant, 12% were multidrug resistant, and no pan-resistant isolates were identified. CONCLUSION: For five years of surveillance, we observed an increase in the number and geographic spread of clinical cases and an increase in fluconazole resistance. These observations emphasise the need for improved measures to mitigate spread.

Identificación de aislamientos de Candida auris recuperados a través de la vigilancia por laboratorio en Colombia: un reto para el diagnóstico / Identification of Candida auris isolates recovered through laboratory surveillance in Colombia: a challenge for diagnostic

Resumen Objetivo: Comparar los resultados obtenidos de diferentes sistemas de identificación de C. auris. Métodos: Análisis descriptivo con datos recopilados durante 2016-19 mediante la vigilancia nacional. Se evaluaron los resultados generados por los sistemas MicroScan, Phoenix BD, VITEK 2 y MALDI-TOF MS de instituciones hospitalarias de 843 aislamientos clínicos sospechosos de C. auris remitidos al INS y se compararon con los resultados generados de confirmación a través de MALDI- TOF MS (Bruker Daltonics) o PCR. Resultados: De los 843 aislamientos clínicos remitidos al INS, el 81,7% fueron confirmados como C. auris mediante MALDI- TOF MS o PCR en el INS y el resto, 18,3%, fueron identificados como otras especies de Candida spp. Las identificaciones correctas enviadas por los laboratorios representaron el 42,4%. MicroScan identificó C. auris principalmente como C. haemulonii, C. guilliermondii, C. albicans y C. famata; Phoenix BD, VITEK 2 y MALDI-TOF MS identificó C. auris como C. haemulonii. Discusión: Estudios señalan que C. auris exhibe una estrecha relación filogenética con C. haemulonii. Las identificaciones discrepantes pueden darse debido a que las bases de datos de los sistemas de diagnóstico son limitadas para este patógeno. Las deficiencias de los sistemas comerciales para la identificación de C. auris deben ser complementados con otros sistemas como MALDI-TOF MS o pruebas moleculares.

Abstract Objective: To compare the identification results obtained by different identification systems of C. auris isolates. Methods: A descriptive study with data collected during the years 2016-19 through surveillance. The results generated by the MicroScan, Phoenix BD, VITEK 2 and MALDI-TOF MS systems of 843 clinical isolates of C. auris submitted to the INS were evaluated and compared with the results generated from confirmation through MALDI-TOF MS (Bruker Daltonics) or PCR. Results: Out of 843 clinical isolates submitted to the INS, 81.7% were confirmed as C. auris by MALDITOF MS or PCR in the INS and the rest, 18.3%, were identified as other species of Candida spp. The correct identifications sent by the laboratories was 42.4%. MicroScan identified C. auris as C. haemulonii, C. guilliermondii, C. albicans and C. famata; Phoenix BD, VITEK 2 and MALDI-TOF MS identified C. auris as C. haemulonii. Discussion: Studies indicate that C. auris exhibits a close phylogenetic relationship with C. haemulonii. In addition, discrepant identifications may occur because the databases of diagnostic systems are limited with reference to this pathogen. The deficiencies of commercial systems for the identification of C. auris must be complemented with other systems such as MALDI-TOF MS or molecular tests.

Ceramide inhibitor myriocin restores insulin/insulin growth factor signaling for liver remodeling in experimental alcohol-related steatohepatitis.

BACKGROUND AND AIM: Alcohol-related liver disease (ALD) is mediated in part by insulin resistance. Attendant dysregulation of lipid metabolism increases accumulation of hepatic ceramides that worsen insulin resistance and compromise the structural and functional integrity of the liver. Insulin and insulin growth factor (IGF) stimulate aspartyl-asparaginyl-ß-hydroxylase (AAH), which promotes cell motility needed for structural maintenance and remodeling of the liver. AAH mediates its effects by activating Notch, and in ALD, insulin/IGF signaling, AAH, and Notch are inhibited. METHOD: To test the hypothesis that in ALD, hepatic ceramide load contributes to impairments in insulin, AAH, and Notch signaling, control and chronic ethanol-fed adult Long-Evans rats were treated with myriocin, an inhibitor of serine palmitoyl transferase. Livers were used to assess steatohepatitis, insulin/IGF pathway activation, and expression of AAH-Notch signaling molecules. RESULTS: Chronic ethanol-fed rats had steatohepatitis with increased ceramide levels; impairments in signaling through the insulin receptor, insulin receptor substrate, and Akt; and decreased expression of AAH, Notch, Jagged, Hairy-Enhancer of Split-1, hypoxia-inducible factor 1α, and proliferating cell nuclear antigen. Myriocin abrogated many of these adverse effects of ethanol, particularly hepatic ceramide accumulation, steatohepatitis, and impairments of insulin signaling through Akt, AAH, and Notch. CONCLUSIONS: In ALD, the histopathology and impairments in insulin/IGF responsiveness can be substantially resolved by ceramide inhibitor treatments, even in the context of continued chronic ethanol exposure.

Outbreak of Rocky Mountain spotted fever in Córdoba, Colombia.

Rocky Mountain spotted fever (RMSF) is a tick-borne disease caused by the obligate intracellular bacterium Rickettsia rickettsii. Although RMSF was first reported in Colombia in 1937, it remains a neglected disease. Herein, we describe the investigation of a large cluster of cases of spotted fever rickettsiosis in a new area of Colombia.

Outbreak of Rocky Mountain spotted fever in Córdoba, Colombia

Rocky Mountain spotted fever (RMSF) is a tick-borne disease caused by the obligate intracellular bacterium Rickettsia rickettsii. Although RMSF was first reported in Colombia in 1937, it remains a neglected disease. Herein, we describe the investigation of a large cluster of cases of spotted fever rickettsiosis in a new area of Colombia.

A survey of antibodies against Rickettsia rickettsii and Ehrlichia chafeensis in domestic animals from a rural area of Colombia.

In a rural area of Colombia endemic for Rocky Mountain spotted fever, we performed indirect immunofluorescent antibody assays for Rickettsia spp. and Ehrlichia spp. using sera from randomly sampled dogs and horses to test the use of domestic animals as possible sentinels. Antibodies against Ehrlichia spp. were detected in 8 dogs (31.8%). Antibody titers against Rickettsia rickettsii antigen were positive in 4 dogs (18.2%) and 26 horses (16.3%). These values, albeit not directly comparable, are lower than those previously reported for humans in this region. A systemic approach to understanding dynamics of transmission is needed before implementing the use of domestic animals for disease surveillance activities.