Background The immunological factors involved in protection against the disease caused by SARS-CoV-2 are insufficiently defined and understood. However, previous knowledge pertaining to the related SARS virus and other human coronaviruses may prove useful. Population-based serosurveys measuring anti-SARS-CoV-2 antibodies may provide a pattern for estimating infection degrees and observing the development of the epidemic. In this study, we aimed to investigate the persistence of antibody against the SARS-CoV-2 in recovered patients in Al Madinah region of Saudi Arabia. Materials and methods A total of 150 recovered COVID-19 patients participated in this study. All the patients tested positive for the presence of SARS-CoV-2 RNA, using qualitative RT-PCR. An ELISA was used to measure anti-Spike (S) IgG antibodies in serum samples and screen for their persistence at various time points post-infection. Results The patients were categorized as asymptomatic (27.3%), mild (28%) and moderate (44.7%) according to the disease severity. Amongst them, 35.3% were females (n=53) and 64.7% were males (n=97). Significant anti-S IgG antibody levels were observed among the different groups, with the patients in moderate group exhibiting the highest levels followed by the mild group; while the lowest levels were detected among the asymptomatic. There was a significant positive correlation between the patients’ age and anti-S IgG antibody concentrations (Pearson r=0.45; p<0.001). Conclusion Our findings provide a solid evidence to support the use of an anti-S IgG ELISA as a diagnostic tool to indicate SARS-CoV-2 infection. IgG seropositivity was sustained in recovered patients up to a hundred days' post-infection, the latest time point for antibody measurement in our study. Ours is the first report in Saudi Arabia to investigate the durability of humoral immune response in recovered COVID-19 patients.

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). To assess the effect of COVID-19 disease on hematology, coagulation profiles, renal and liver function over the course of the disease, the following laboratory tests were performed: WBCs per mm3, lymphocytes count, Platelet, D-dimmer, AST, Albumin, LDH, Ferritin, CRP, blood culture and viral loads. Patients were grouped according to their initial viral load (Group1: low viral load (L), Group 2: moderate viral load (I), and Group 3, high viral load (H)). The study population median age of the patients was 58 years, and 69% were male. Generally, all patients were admitted to the intensive care unit. Most of the patients (79.5%) had an intermediate viral load, 14.5% had a high viral load, and 5.7% had a low viral load. The Kusakal-Walli’s test revealed a significant difference in the levels of white blood cells, lymphocytes, platelet, D-dimer, AST, CRP, and ferritin (p <0.0001). One hundred twenty-two isolates were recovered from 5362 blood cultures; where as 75% were multiple resistant to three classes of antibiotics and more. True bacteremia was most commonly caused by Klebsiella pneumoniae (45%), Acinetobacter baumannii (30%), and C. albicans (7%). The potential risk factors of advanced age, lymphopenia, D-dimer concentrations greater than 2µg/mL, and ferritin concentrations greater than 400ng/mL may assist clinicians to improve the management of the case and reduce mortality.

The spread of extended spectrum beta lactamase (ESBL) producing Enterobacteriaceae has dramatically increased and become a major public health concern worldwide. The main purpose of the study was to determine antibiotic resistance patterns among ESBL producing Enterobacteriaceae isolated from clinical specimen of pilgrims during Hajj in Medinah, Saudi Arabia. A total of 69 consecutive non-duplicate isolate Enterobacteriaceae were examined by cultured in selective and non-selective media, therefore between June and august 2019. All isolates were identified and tested for susceptibility by the VITAK II. Detection of ESBL was carried out by double disk synergy test technique. Of 69 of Enterobacteriaceae isolates, 3 isolates were associated with multidrug resistance (MDR) phenotype. All isolates showed variable resistance levels to all antibiotics used here expect to colistin, where they were all colistin-sensitive. Sensitivity of 98% was observed to amikacin. 12 out of 69 E. coli isolates were positive for ESBLs by phenotypic methods. 16 out of 69 Klebsiella pneumoniae isolated were ESBL producers. Most of the ESBLs were from urine (45%). The main risk factors for ESBL in these children were previous exposure to antimicrobials and prolonged hospital stay and female gender (68%). No resistance was recorded for the following combinations of antibiotic: amikacin plus nitrofurantoin, amikacin plus piperacillin-tazobactam. Carbapenems are the most sensitive and reliable treatment options for infections caused by ESBL producing Enterobacteriaceae. Amikacin plus piperacillin-tazobactam are good alternatives. Our study documented the high antimicrobial resistance of ESBL producing Enterobacteriaceae to many first line antibiotics currently used to treatment patients, and this implies the need to continuously revise the local guidelines used for optimal empirical therapy for patients.

The coronavirus disease 2019 (COVID-19) virus, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is spreading rapidly. The purpose of this study is to explore high risk patients and guiding future management and summarize the results of routine laboratory testing of asymptomatic, mild to moderate, severe and critical COVID-19 in order to define practical indicators for the diagnosis and treatment of COVID-19. A total of 100 confirmed COVID-19 patients from Madinah city, Saudi Arabia, hospitalized between March to June, 2020 were included, and categorized into asymptomatic, mild to moderate, severe and critically ill patients. Fasting blood samples were withdrawn from all patients for estimation of complete blood count, coagulation profile, biochemistry and serology. Patients were grouped on the basis of the interval between symptom onset: group 1 (asymptomatic), group 2 (mild to moderate), group 3 (severe), and group 4 (critical). Laboratory features and their distribution were analysed and compared across the four groups. Combining assessment of clinical and laboratory findings could facilitate early diagnosis of COVID-19 pneumonia. Median age was 51 years old and 85% of the patients were men. Overall, all patients were admitted to hospitals and 42% required ICU treatment. The majority of patients (29%) were diagnosed with mild to moderate disease, 28% of patients were critical, 26% of patients were severe and 17% of patients were asymptomatic. The comparison COVID-19 patients’ four parameters, using Kusakal-Wallis test, showed a significant difference in the levels of lymphocytes, ESR, PT, INR, d-dimer, CK, BUN and ferritin (P <0.05). C-reactive protein greater than 2.97 (0.84-9.18; p<0.0001). The potential risk factors of older age, lymphopenia, d-dimer greater than 1µg/mL and ferritin greater than 500ng/mL could help physicians to identify patients with a poor prognosis at an early stage.