Ethyl glucuronide and ethyl sulfate: a review of their roles in forensic toxicology analysis of alcohol postmortem.

PURPOSE: This review presents the current methods used for determining ethyl glucuronide (EtG) and ethyl sulfate (EtS) concentrations in postmortem specimens, including sample preparation, analysis and the role of EtG and EtS in the postmortem assessment of the extent of alcohol abuse. METHODS: Papers pertaining to postmortem investigation were collected from scientific databases and reviewed. The papers were published between January 2006 and October 2020. RESULTS: Most of the analyses involved postmortem blood and urine samples, with a few reports using other bodily specimens and tissues. The method validation was not conducted for all applications. These reports were mostly intended to present data rather than interpret them, and the lack of effort in relating these ethanol biomarkers with the cause of death and/or determination of the time of deaths due to ethanol intoxication might decrease the applicability of these makers after a promising start between 2006 and 2010. Nevertheless, by the beginning of 2020, papers investigating ethanol biomarkers were still increasing. A considerable number of methods used liquid chromatography coupled with mass spectrometry (LC-MS) techniques that require less sample preparation (e.g., protein precipitation extraction, dilution, filtration, and centrifugation). Although solid-phase extraction can be applied, only three applications were reported. CONCLUSIONS: Matrix effects can be a substantial challenge in analytical methods based on LC-MS because they directly affect the ionization of analytes. However, these problems can be avoided due to the high cutoff values used to identify positive results for these ethanol biomarkers, which are often above 0.1-1 mg/L, and using internal standards. Research on using tissue specimens is recommended as most of the reported results on this type of specimen were promising.

Seroprevalence of community-acquired atypical bacterial pneumonia among adult COVID-19 patients from a single center in Al Madinah Al Munawarah, Saudi Arabia: A retrospective cohort study.

OBJECTIVES: To investigate the seroprevalence of the community-acquired bacterial that causes atypical pneumonia among confirmed severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) patients. METHODS: In this cohort study, we retrospectively investigated the seroprevalence of Chlamydia pneumoniae, Mycoplasma pneumoniae, and Legionella pneumophila among randomly selected 189 confirmed COVID-19 patients at their time of hospital presentation via commercial immunoglobulin M (IgM) antibodies against these bacteria. We also carried out quantitative measurements of procalcitonin in patients' serum. RESULTS: The seropositivity for L. pneumophila was 12.6%, with significant distribution among patientsolder than 50 years (χ2 test, p=0.009), while those of M. pneumoniae was 6.3% and C. pneumoniae was 2.1%, indicating an overall co-infection rate of 21% among COVID-19 patients. No significant difference (χ2 test, p=0.628) in the distribution of bacterial co-infections existed between male and female patients. Procalcitonin positivity was confirmed amongst 5% of co-infected patients. CONCLUSION: Our study documented the seroprevalence of community-acquired bacteria co-infection among COVID-19 patients. In this study, procalcitonin was an inconclusive biomarker for non-severe bacterial co-infections among COVID-19 patients. Consideration and proper detection of community-acquired bacterial co-infection may minimize misdiagnosis during the current pandemic and positively reflect disease management and prognosis.

COVID-19 with underdiagnosed influenza B and parainfluenza-2 co-infections in Saudi Arabia: Two case reports.

The emerging of the COVID-19 pandemic is currently challenging for the public health system globally. Beyond SARS-CoV-2 pathogenicity, co-infections with recycling respiratory pathogens, whether bacterial, viral, or fungal, might increase disease symptoms, morbidity, and mortality. In this study, we reported two COVID-19 cases in the early phase of the virus spread in Saudi Arabia with underdiagnosed respiratory viruses' co-infections, influenza B and Parainfluenza-2, detected retrospectively. Fortunately, both patients recovered and were discharged home. Underestimation of co-infection among COVID19 patients might lead to hospital stay prolongation and increases morbidity and mortality. Therefore, it is crucial to consider and screen for co-infecting pathogens among COVID-19 patients and those with risk factors.

Respiratory tract samples, viral load, and genome fraction yield in patients with Middle East respiratory syndrome.

BACKGROUND: Analysis of clinical samples from patients with new viral infections is critical to confirm the diagnosis, to specify the viral load, and to sequence data necessary for characterizing the viral kinetics, transmission, and evolution. We analyzed samples from 112 patients infected with the recently discovered Middle East respiratory syndrome coronavirus (MERS-CoV). METHODS: Respiratory tract samples from cases of MERS-CoV infection confirmed by polymerase chain reaction (PCR) were investigated to determine the MERS-CoV load and fraction of the MERS-CoV genome. These values were analyzed to determine associations with clinical sample type. RESULTS: Samples from 112 individuals in which MERS-CoV was detected by PCR were analyzed, of which 13 were sputum samples, 64 were nasopharyngeal swab specimens, 30 were tracheal aspirates, and 3 were bronchoalveolar lavage specimens; 2 samples were of unknown origin. Tracheal aspirates yielded significantly higher MERS-CoV loads, compared with nasopharyngeal swab specimens (P = .005) and sputum specimens (P = .0001). Tracheal aspirates had viral loads similar to those in bronchoalveolar lavage samples (P = .3079). Bronchoalveolar lavage samples and tracheal aspirates had significantly higher genome fraction than nasopharyngeal swab specimens (P = .0095 and P = .0002, respectively) and sputum samples (P = .0009 and P = .0001, respectively). The genome yield from tracheal aspirates and bronchoalveolar lavage samples were similar (P = .1174). CONCLUSIONS: Lower respiratory tract samples yield significantly higher MERS-CoV loads and genome fractions than upper respiratory tract samples.

Rotavirus gastroenteritis and strain diversity in Saudi Arabia. Current status and future prospects.

OBJECTIVE: To determine the epidemiological profile and strain diversity in the light of recent published studies to provide an updated comprehensive picture of the significance of the effect of this virus in Saudi Arabia. METHODS: The epidemiology, disease burden, and strain diversity of rotavirus in Saudi Arabia were reviewed using 22 studies of rotavirus and the etiology of diarrhea. We reviewed the studies conducted between 1982 and 2005 as well as the 2 recently published studies in 2008. This study took place in King Fahd Hospital, Maddina, Kingdom of Saudi Arabia. RESULTS: In Saudi Arabia, a review published in 2006 showed that rotavirus prevalence ranged from 10-46%, with a median prevalence of 30% of cases of gastroenteritis. Recent studies in the country however showed a lower detection rates (18% and 12%). These 2 studies described the distribution of G and P types of rotavirus circulating in Saudi Arabia and demonstrated the presence of serotype G1-G4, G9, G12, P[4], P[6], and P[8]. CONCLUSION: These results have importance regarding a future rotavirus immunization strategies in Saudi Arabia, and underscore the need for a countrywide monitoring a rotavirus G- and P-types before the introduction of a rotavirus vaccine.

Molecular epidemiology of rotavirus diarrhea among children in Saudi Arabia: first detection of G9 and G12 strains.

In anticipation of rotavirus vaccine introduction in Saudi Arabia, this study was undertaken to determine the distribution of the G and P genotypes of rotaviruses in order to examine whether there was any emerging serotype or unusual strain circulating in children in Saudi Arabia. Of 984 stool specimens collected between 17 April 2004 and 16 April 2005, rotavirus was detected by an enzyme-linked immunosorbent assay in 187 (19%) diarrheal children less than 5 years of age. Of these, 160 (86%) were classified into G and P genotypes as follows: G1P[8] (44%), G2P[4] (20%), G9P[8] (11%), G12P[8] (4%), and G3P[8] (4%). RNA polyacrylamide gel electrophoresis identified 94 (50%) specimens as long RNA patterns, 30 (16%) specimens as short RNA patterns, and 1 mixed infection. Only a single long RNA electropherotype was identified for seven specimens containing G12P[8] rotavirus. RNA-RNA hybridization demonstrated that the G12P[8] strains were similar in their genomic constellation to locally cocirculating strains and to a Nepalese G12P[8] strain. The Saudi Arabian G12 VP7 gene had a 99% nucleotide sequence identity with Nepalese and Indian G12 VP7 genes and belonged to the third lineage. This study is the first to describe the distribution of rotavirus G and P types and also the first to identify G9P[8] and G12P[8] strains in the country.

Characterization of rotavirus strains detected among children and adults with acute gastroenteritis in Gizan, Saudi Arabia.

OBJECTIVE: To assess the circulating rotavirus strains among hospitalized children and adults in Gizan City. METHODS: This cross-sectional study was based in 5 hospitals in the Gizan area. Stool samples were collected between November 2004 and March 2005, from sequential patients with acute, dehydrating diarrhea. Rotavirus antigen was detected in stool by enzyme-linked immunosorbent assay. The diversity of rotavirus strains was investigated using electropherotying and reverse transcription-polymerase chain reaction amplification of the VP7 and VP4 genes (G and P genotyping). RESULTS: Rotavirus was detected in 54 of 454 (12%) subjects. The ages of those infected with rotavirus ranged from 15 days to 20 years, with a median age of 36 months. The highest rotavirus detection rate (24%) occurred in children aged 48-59 months. Overall, 50 (93%) of strains could be assigned both a G- and P-type; G1P[8] was the most frequently detected strain type (n=48, 89%) with one rotavirus each of G2P[4] and G9P[8]. CONCLUSION: Rotavirus strains circulating in Gizan would be well covered by current rotavirus vaccines. Rotavirus serotype G9 has been detected in Saudi Arabia for the first time. Continued surveillance of rotavirus strains is required.

Rotavirus infection in Saudi Arabia.

BACKGROUND: Human rotavirus, an important causative agent of severe gastroenteritis in infants and young children worldwide, leads to high morbidity in both developing and developed countries, including Saudi Arabia, and high mortality in developing countries. Effective control depends upon an accurate understanding of disease burden and the relative importance of circulating serotypes. METHODS: We examined the epidemiology and disease burden of rotavirus in Saudi Arabia through a review of 22 published studies of rotavirus and the aetiology of diarrhoea carried out from 1982 to 2003. RESULTS: The prevalence of rotavirus infection ranged between 10% to 46% with a median of 30%. Most cases were among children less than 2 years of age, and particularly in the first year of life. There were significant differences in seasonality within Saudi Arabia, with increased infection during winter in some cities and during summer in others. G1 was the predominant serotype followed by G4, G3 and G2, in 4 studies where strains had been G-typed. The prevalence of nontypeable strains ranged from 11.0% to 31.3%. No data were available on P types. Results of electropherotyping in 4 studies revealed that the long electropherotype was predominant. CONCLUSION: Rotavirus is an important cause of severe diarrhoea in Saudi children. However, the available data on rotavirus strains in circulation are limited and there is an urgent need for up-to-date and comprehensive studies to evaluate rotavirus strains in circulation and identify unusual types that could be incorporated into future vaccines.