CD4+ T-lymphopenia in HIV negative tuberculous patients at King Khalid University Hospital in Riyadh, Saudi Arabia

Tuberculosis (Tb) is a chronic infectious disease in which the cellular immunity (specifically CD4+ and CD8 lymphocytes) provides the most important defense in controlling infection. CD4 lymphopenia is a well-defined risk factor for the development of active tuberculosis in patients infected with Human Immunodeficiency Virus. In HIV - negative patients, CD4 and CD8 cell count suppression has been associated with Tb infection. Our study was designed to deter mine the baseline and post-treatment values of CD4 and CD8 in HIV negative patients diagnosed with active Tb in Saudi Arabian patients. We recruited twentyeight, non-HIV patients with tuberculosis for the study group comprising 16 males and 12 females with either disseminated or localized active Tb infection. Two control groups were selected - one of twenty one matched healthy controls and the second of fortytwo subjects from pool of controls of an ongoing study in same population for normal CD4 and CD8 counts. The baseline pre-treatment CD4 and CD8 counts in the study group were significantly lower than either control group. Specifically the mean ± SD of CD4 counts were 556.79 ± 298.81 in the study group vs 1,132.38 ± 259.90 in control group 1 and 1,424.38 ± 870.98 in control group 2 (p 0.000). Likewise the CD8 counts in the study group were 1,136.00 ± 512.06 vs. 1,461.90 ± 367.02 in control group 1 and 1,495.90 ± 565.32 in control group 2 (p 0.000) respectively. After treatment of tuberculosis, the study patients experienced a significant increase in their mean ± SD CD4 and CD8 cell counts, from 556.79 ± 297.81 to 954.29 ± 210.90 for CD4 cells (p 0.005) and 1136.00 ± 512.06 to 1,316.54 ± 286.17 for CD8 cells (p 0.002). Analysis of study patients with disseminated disease found significantly lower CD4 cells (but not lower CD8 cells) compared to study patients with localized disease, both at baseline and after treatment. The mean ± SD baseline CD4 cells were 247.60 ± 187.80 with disseminated vs 728.56 ± 186.32 for localized disease (p = 0.000) which rose to 842.30 ± 93.55 vs 1016.50 ± 233.51 (p = 0.033) respectively. We conclude that tuberculosis may be associated with CD4 and CD8 lymphopenia even in patients without human immunodeficiency virus infection, there was the tendency of recovery towards normality especially of the CD4 and CD8 counts after treatment, and that disseminated disease is associated specifically with profound CD4 lymphopenia

Environmental Geotechnics: Challenges and Opportunities in the Post COVID-19 World

The outbreak of the COVID-19 pandemic not only created a health crisis across the world but is expected to negatively impact the global economy and societies at a scale that maybe larger than the 2008 financial crisis. Simultaneously, it has inevitably exerted many negative consequences on the geoenvironment upon which human beings depend. The current article articulates the role of environmental geotechnics to elucidate and mitigate the effects of the current pandemic. It is the belief of all authors that the COVID-19 pandemic presents significant challenges, but also opportunities for the development of our field. Our discipline should make full use of our professional skills and expertise to look for development opportunities from this crisis, to highlight our discipline’s irreplaceable position in the global fight against pandemics, and to contribute to the health and prosperity of our communities, so as to better serve humankind. In order to reach this goal, while taking into account the specificity of the SARS-CoV-2 and the uncertainty of its environmental effects, it is believed that more emphasis should be placed on the following research directions: pathogen-soil interactions, isolation and remediation technologies for pathogen-contaminated sites, new materials for pathogen-contaminated soil, recycling and safe disposal of medical wastes, quantification of uncertainty in geoenvironmental and epidemiological problems, emerging technologies and adaptation strategies in civil, geotechnical, and geoenvironmental infrastructure, pandemic-induced environmental risk management, and model pathogen transport and fate in geoenvironment, among others. Moreover, COVID-19 has made it clear to the environmental geotechnics community the importance of urgent international cooperation and of multidisciplinary research actions that must extend to a broad range of scientific fields, including medical and public health disciplines, in order to meet the complexities posed by the COVID-19 pandemic

Detection of Salmonella typhi agglutinins in sera of patients with other febrile illnesses and healthy individuals

Background and Purpose: Widal test is frequently applied for the detection of Salmonella agglutinins to diagnose Salmonella enterica serotype Typhi infection. There are however a number of controversies challenging the diagnostic utility of this test. This study was performed to determine the prevalence of Salmonella agglutinins in patients with other febrile illnesses and healthy blood donors.Materials and Methods: Sera from 50 healthy blood donors were compared for the presence of Salmonella agglutinins in various groups of patients with other febrile illnesses using Widal test in the division of Serology and Immunology at King Khalid University Hospital, Riyadh. The patient groups of other febrile illnesses included infections with Beta-hemolytic streptococcus (n = 50), Brucella (n = 46), Helicobacter pylori (n = 24), Treponema pallidum (n = 30), Toxoplasma (n = 44), and other parasites (n = 20).Results: Majority of the patients and normal individuals were tested positive for Widal test at dilution of less than 1 : 40 both for the O (62.5%) and H (64.6%) antigen. A decreasing trend in Widal reactivity was observed with increasing dilutions of the serum samples. At 1 : 160 titer, which is generally considered as a cut off point for positive Widaltest, 6.4 and 11% individuals had positive Widal test for O and H Salmonella antigens, respectively.Conclusion: Detection of a significant number of positive Widal tests in conditions where it is expected to be nonreactive appears to be a serious problem in making a correct diagnosis of typhoid fever, thus challenging the diagnostic utility of the Widal test

Investigating a rare methicillin-resistant Staphylococcus aureus strain: first description of genome sequencing and molecular characterization of CC15-MRSA

Abiola C Senok,1 Ali M Somily,2 Peter Slickers,3,4 Muhabat A Raji,5 Ghada Garaween,5 Atef Shibl,5 Stefan Monecke,3,4,6 Ralf Ehricht3,4 1Department of Basic Science, College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai, United Arab Emirates; 2Department of Pathology and Laboratory Medicine, College of Medicine, King Khalid University Hospital and King Saud University, Riyadh, Saudi Arabia; 3Alere Technologies GmbH, Jena, Germany, 4InfectoGnostics Research Campus, Jena, Germany; 5Department of Microbiology and Immunology, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia; 6Institute for Medical Microbiology and Hygiene (IMMH), Technische Universität Dresden, Dresden, Germany Purpose: Methicillin resistant Staphylococcus aureus CC15 strains (CC15-MRSA) have only been sporadically described in literature. This study was carried out to describe the genetic make-up for this rare MRSA strain.Methods: Four CC15-MRSA isolates collected in Riyadh, Saudi Arabia, between 2013 and 2014 were studied. Two isolates were from clinical infection and 2 from retail meat products. Whole genome sequencing was carried out using Illumina HiSeq2500 genome analyzer.Results: All the CC15-MRSA isolates had the multilocus sequence typing profile ST1535, 13–13-1–1-81-11-13, which is a single locus variant of ST15. Of the 6 contigs related to the SCC element, one comprised a recombinase gene ccrAA, ccrC-PM1, fusC and a helicase, another one included mvaS, dru, mecA and 1 had yobV and Q4LAG7. The SCC element had 5 transposase genes, namely 3 identical paralogs of tnpIS431 and 2 identical paralogs of tnpIS256. Two identical copies of a tnpIS256-based insertion element flank the aacA-aphD gene. Two copies of this insertion element were present with 1 located in the SCC element and another inserted into the sasC gene. A short 3 kb region, which lacks any bacteriophage structural genes and site-specific DNA integrase, was inserted into the hlb gene. The hsdM and the 5’-part of the hsdS gene are replaced by a copy of the hsdM/hsdS paralogs from nSab giving rise to a new chimeric paralog of hsdS in vSaa.Conclusion: CC15-MRSA shows a novel SCCmecV/SCCfus composite element. Its variant of hsdM/hsdS probably facilitated uptake of foreign mobile genetic elements that promoted emergence of CC15-MRSA. Close surveillance is needed to monitor spread and emergence of further CC15 MRSA strains. Keywords: whole genome sequencing, MRSA, MLST, clonal complex, SCCmec, Saudi Arabi