Case report of Curtobacterium isolated from a catheter tip sample misidentified as Cronobacter.

The Curtobacterium genus is a member of the family Microbacteriaceae, and Curtobacterium species are recognized as plant pathogens. The aim of this study was to investigate a dubious result of species identification for an infection located on a catheter tip of a patient with Covid-19. A strain isolated from a catheter tip sample, identified by VITEK® 2 as Cronobacter spp., was submitted to polyphasic analysis: Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) using VITEK® MS, real-time polymerase chain reaction targeting dnaG gene, and 16S rRNA full gene Sanger sequencing analysis for confirmation. The strain presented negative result using qPCR and could not identified by MALDI-TOF MS. 16S rRNA full gene Sanger sequencing analysis identified the strain as Curtobacterium spp. The Gram-variable characteristic (Gram-negative instead of Gram-positive) of the isolated strain was the responsible for the misidentification by VITEK® 2 and VITEK® MS did not identify the strain. 16S rRNA full gene sequencing analysis identified the strain as Curtobacterium genus, but other complementary techniques are necessary to identify at species level.

Tuberculin skin testing in HIV-infected patients in Campo Grande, Mato Grosso do Sul State, Brazil

A cross-sectional study on HIV/AIDS was carried out in 108 outpatients from the university hospital of the Federal University of Mato Grosso do Sul, Campo Grande, Brazil, from July to December 2008, to investigate latent tuberculosis infection using the tuberculin skin test (TST). The prevalence of positive results was 13.9 percent. The CD4+ T cell count (p = 0.091) and the diagnosis time (p = 0.010) were statistically significant when compared with TST positivity. In the cohort of HIV/AIDS patients who had latent tuberculosis infection, the median diagnosis time was eight years. Undetectable viral load presented significant association (p = 0.046) with tuberculosis infection. The fact that numerous individuals with HIV/AIDS infection presented a negative reaction to the tuberculin skin test is probably related to alterations in the cellular immune response induced by HIV infection. The tuberculin test is a useful tool for the detection of latent tuberculosis infection and should be performed in all HIV/AIDS individuals at the time of the diagnosis and on a yearly basis, if negative. Both the early identification of the tuberculosis infection by the tuberculin skin test at the moment of immunological restoration and chemoprophylaxis in infected individuals are mechanisms to control HIV/AIDS and tuberculosis coinfection.