Association between human leukocyte antigen alleles and COVID-19 disease severity.

Background: the human leukocyte antigen (HLA) loci have been widely characterized to be associated with viral infectious diseases. Several studies including various ethnic groups and populations suggested associations between certain HLA alleles and SARS-CoV-2 infection. Despite the numerous associations identified, the role of HLA polymorphisms in determining the individual response to SARS-CoV-2 infection is controversial among different Saudi populations.

Identification of the novel HLA-B*53:69 allele by sequencing-based typing.

The HLA-B*53:69 allele differs from HLA-B*53:01:01:01 by two nucleotide changes in exon 3.

Combined effect of age and body mass index on postoperative mortality and morbidity in laparoscopic cholecystectomy patients.

Background: Previous studies have assessed the impact of age and body mass index (BMI) on surgery outcomes separately. This retrospective cohort study aimed to investigate the combined effect of age and BMI on postoperative mortality and morbidity in patients undergoing laparoscopic cholecystectomy.

Methods: Data from the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database for laparoscopic cholecystectomy patients between 2008 and 2020 were analyzed.

Case Report: COVID-19 Infection of a Transplanted Heart Simulating Cellular Rejection.

Contemporary reports showed that solid organ transplantation patients who contract SARS-CoV-2 infection have a high mortality rate. There are sparse data about recurrent cellular rejections and the immune response to the SARS-CoV-2 virus in patients after heart transplantation. Herein, we report a case of a 61-year-old male post-heart transplant patient who tested positive for COVID-19 and developed mild symptoms 4 months after transplantation.

Identification of the novel HLA-C*04:495 allele by sequencing-based typing.

The HLA-C*04:495 allele differs from HLA-C*04:01:01:31 by two nucleotide changes in the 5'UTR and exon 5.

Age/BMI is a Stronger Predictor of Death in COVID-19 Patients than Age Alone: A Pilot Study.

The objective of this study was to investigate the effect of age and BMI on the risk of death in patients with coronavirus disease 2019 (COVID-19). A cohort of 206 Saudi COVID-19 patients was included in this study. Data on age, BMI, hospitalization, comorbidities, and death were collected and analyzed.

Identification of the novel HLA-A*74:03:03 allele by sequencing-based typing.

HLA-A*74:03:03 differs from A*74:03:01 by a synonymous mutation at nucleotide 1948 in exon 4.

Identification of the novel HLA-DQB1*03:483 allele by sequencing-based typing.

A single nucleotide change in exon 1 of HLA-DQB1*03:01:01:03 results in the novel HLA-DQB1*03:483 allele.

Correlation between ABO Blood Group Phenotype and the Risk of COVID-19 Infection and Severity of Disease in a Saudi Arabian Cohort.

Background: Disease severity among patients infected with SARS-CoV-2 varies remarkably. Preliminary studies reported that the ABO blood group system confers differential viral susceptibility and disease severity caused by SARS-CoV-2. Thus, differences in ABO blood group phenotypes may partly explain the observed heterogeneity in COVID-19 severity patterns, and could help identify individuals at increased risk.

Association of KIR gene polymorphisms with COVID-19 disease.

Background: Natural killer (NK) cells play an essential role against viruses. NK cells express killer cell immunoglobulin-like receptors (KIRs) which regulate their activity and function. The polymorphisms in KIR haplotypes confer differential viral susceptibility and disease severity caused by infections.

Kinetics of antibody response in critically ill patients with Middle East respiratory syndrome and association with mortality and viral clearance.

The objective of this study is to examine the IgG antibody response in critically ill patients with the Middle East respiratory syndrome (MERS) and to examine the association of early antibody response with mortality and viral clearance. We collected blood samples from 40 consecutive real-time reverse transcription-polymerase chain reaction (rRT-PCR) confirmed critically ill MERS patients on ICU days 1, 3, 7, 14 and 28. MERS-CoV antibodies were detected by enzyme-linked immunosorbent assay (ELISA), using wells coated with MERS-CoV S1 antigen.

Characterization of the novel HLA-B*57:02:01:03 allele by sequencing-based typing.

Two-nucleotide changes in the 3' UTR of HLA-B*57:02:01:01 result in the novel HLA-B*57:02:01:03 allele.

Characterization of the novel HLA-A*68:277 allele by sequencing-based typing.

A single nucleotide change in exon 1 of HLA-A*68:01:01:02 results in the novel HLA-A*68:277 allele.

Characterization of the novel HLA-A*31:199 allele by sequencing-based typing.

A single nucleotide change in exon 4 of HLA-A*31:01:02:31 results in the novel HLA-A*31:199 allele.

Chances of Finding Matched Unrelated Donors for Saudi Patients in Need of Hematopoietic Stem Cell Transplantation.

Finding HLA-matched donors for patients in need of hematopoietic stem cell transplantation (HSCT) stands a better chance in their own ethnic group. This information led many nations to establish unrelated stem cell donor registries. We started our Saudi Stem Cell Donor registry (SSCDR) in 2011.

Identification of a novel HLA-B*18 variant, HLA-B*18:01:01:52, in a Saudi individual.

A single nucleotide change in the 3' UTR of HLA-B*18:01:01:01 results in the novel HLA-B*18:01:01:52 allele.

Identification of a novel HLA-A*31 variant, HLA-A*31:01:02:31, in a Saudi individual.

A single nucleotide change in the 5' UTR of A*31:01:02:01 results in the novel HLA-A*31:01:02:31 allele.

HLA-A, -B, -C, -DRB1, -DQB1, and -DPB1 Allele and Haplotype Frequencies of 28,927 Saudi Stem Cell Donors Typed by Next-Generation Sequencing.

Human leukocyte antigen (HLA) allele and haplotype frequency distribution varies widely between different ethnicities and geographical areas. Matching for HLA alleles is essential for successful related and unrelated stem cell transplantation. Among the Saudi population, data on HLA alleles and haplotypes are limited.

Inflammatory Response and Phenotyping in Severe Acute Respiratory Infection From the Middle East Respiratory Syndrome Coronavirus and Other Etiologies.

Objectives: In this study, we evaluated the inflammatory response in patients with severe acute respiratory infection due to the Middle East respiratory syndrome and non-Middle East respiratory syndrome and assessed the presence of distinct inflammatory subphenotypes using latent class analysis.

Design: Prospective cohort study.

Setting: A tertiary care ICU in Riyadh, Saudi Arabia.

The novel HLA-DQB1*06:03:01:06 allele identified in a Saudi individual.

HLA-DQB1*06:03:01:06 differs from HLA-DQB1*06:03:01:01 by a single nucleotide substitution in intron 2.

Novel HLA-B*81:02:02 allele identified in a Saudi individual.

HLA-B*81:02:02 differs from HLA-B*81:02 by a synonymous substitution in exon 5.

Evolving sequence mutations in the Middle East Respiratory Syndrome Coronavirus (MERS-CoV).

Background: Middle East respiratory syndrome coronavirus (MERS-CoV) has continued to cause sporadic outbreaks of severe respiratory tract infection over the last 8 years.

Methods: Complete genome sequencing using next-generation sequencing was performed for MERS-CoV isolates from cases that occurred in Riyadh between 2015 and 2019. Phylogenetic analysis and molecular mutational analysis were carried out to investigate disease severity.