Deficiency of antioxidants and increased oxidative stress in COVID-19 patients: A cross-sectional comparative study in Jigawa, Northwestern Nigeria.

INTRODUCTION: The COVID-19 is a pandemic caused by SARS-CoV-2 which has infected over 74 million people, killing more than 1,600,000 million people around the world as of 17th December 2020. Accumulation of free radicals coupled by weakened antioxidant system leads to oxidative stress, which will further worsen respiratory diseases, COVID-19 inclusive. This study aimed to examine the levels of some antioxidants and oxidative stress markers in COVID-19 patients. METHODS: This was a cross-sectional comparative study in which 50 COVID-19 symptomatic patients who were on admission at the COVID-19 isolation center in Jigawa, Northwestern Nigeria, were recruited. Twenty one (21) apparently healthy individuals were included as controls. Levels of antioxidant trace elements (Se, Zn, Mg, Cu and Cr), 8-isoprostaglandin F2 alpha and malondialdehyde in the plasma and erythrocytes activity of glutathione, glutathione peroxidase, superoxide dismutase and catalase were determined. RESULTS: The plasma concentrations of vitamins A, C and E were significantly lower (p < 0.001) in COVID-19 patients than controls. Activities of glutathione, glutathione peroxidase, catalase and superoxide dismutase were lower in COVID-19 subjects than controls (p < 0.001). The concentrations of Se, Zn, Mg and Cu were significantly lower (p < 0.001; p = 0.039; p < 0.001; and p < 0.001), respectively, in COVID-19 patients than controls, while chromium showed no significant difference (p = 0.605). Oxidative stress marker, 8-isoprostaglandin F2 alpha, was significantly higher (p = 0.049), while malondialdehyde was lower (p < 0.001) in COVID-19 patients than controls. CONCLUSION: In conclusion, COVID-19 patients are prone to depleted levels of antioxidant substances due to their increase utilization in counterbalancing the negative effect of free radicals. Furthermore, COVID-19 infection with other comorbidities, such as malaria, hypertension and diabetes, are at higher risk of developing oxidative stress.

An elevated 8-isoprostaglandin F2 alpha (8-iso-PGF2α) in COVID-19 subjects co-infected with malaria.

INTRODUCTION: the most recently discovered severe acute respiratory syndrome Coronavirus 2 (SARS-COV-2) that causes COVID-19, subjected the entire world in turmoil health-wise and economically. With higher burden of malaria in Nigeria and other sub-Saharan African countries coupled with fragile healthcare system and delivery, these may pose a threat in the diagnosis and management of COVID-19 patients co-infected with malaria. Free radicals have been implicated in the progression and pathogenesis of malaria and COVID-19 through Fenton's reaction and cytokine storm respectively. METHODS: the current research comprises of seventy-four (74) participants; 20 apparently healthy controls and 54 COVID-19 patients (34 among which were co-infected with malaria). Serum levels of 8-iso PGF2α and Alphatocopherol were determined among the study participants using ELISA technique and colorimetric assay, respectively. RESULTS: results revealed statistically significant elevation of 8-iso PGF2α in COVID-19 patients co-infected with malaria compared to COVID-19 patients only, and this may be due to increase production of free radicals. Furthermore, a significant decrease of Alphatocopherol was observed in COVID-19 co-infected with malaria compared to COVID-19 patients due to increase utilization of antioxidants in counterbalancing the negative effect of free radicals generated. CONCLUSION: conclusively, SARS-COV-2 patients co-infected with malaria might be predisposed to oxidative stress and low Alphatocopherol. The increase in oxidative stress is proportional to malaria parasite density and inversely related to Alphatocopherol levels. This implies that oxidative stress is notably higher and such patients may have a severer form of the COVID-19. Increased 8-iso-PGF2α in co-infection and decreased alphatocopherol levels can reflect the severity and adverse outcomes compared to COVID-19 naïve because of their tremendous involvement in the pathogenesis and progression of diseases.

Molecular Detection of Panton Valentine Leukocidin Toxin in Clinical Isolates of Staphylococcus aureus from Kiambu County, Kenya.

Panton-Valentine leukocidin gene is produced by Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus isolates as a pore-forming toxin is largely responsible for skin and soft tissue illnesses. MRSA produces PVL toxins through lukS and lukF proteins causing tissue necrosis by damaging membrane of the defense cells. Presence of PVL toxin was tested from the 54 S. aureus clinical isolates obtained from Thika and Kiambu Level 5 Hospitals, in Kiambu County, Kenya, by Geno Type® MRSA assay (Hain Life Science, Nehren, Germany). DNA was isolated from freshly harvested bacterial cultures by spin column using Geno Type DNA isolation kit. The detection of PVL toxins was performed by amplification of genomic DNA and by reverse hybridization that identifies PVL genes using Geno Type MRSA kit. Out of 138 samples that were collected from patients in Kiambu County, 54 S. aureus isolates were obtained, of which 14 (25.9%; 95% CI = 11.9-38.9) samples had PVL toxins. The isolates that were obtained from the female patients had a higher PVL toxin prevalence of 35.7%, while the isolates collected from the male patients had a lower prevalence of 15.4% (P = 0.09). The pediatrics department had the highest PVL gene prevalence compared to outpatient department and surgical units (P = 0.08). However, the age groups of patients and the hospital attended by patients showed no significant difference in terms of PVL gene prevalence (P = 0.26). Therefore, the patients' gender and hospital units were not significantly associated with PVL gene prevalence (P = 0.08). This study shows that PVL positive isolates occur in the sampled hospitals in the county and female as well as children must be taken into consideration among patients with wound infections when isolating S. aureus.

Phenotypic analysis and antibiotic susceptibility of methicillin-resistant Staphylococcus aureus in Kiambu County, Kenya.

INTRODUCTION: Methicillin resistant Staphylococcus aureus (MRSA) causes illness to people and can be picked up from both healthcare facilities and the environment leading to high morbidity and mortality. The study was aimed at identifying phenotypic characteristics of Methicillin-Resistant Staphylococcus aureus and determine the antibiotic susceptibility pattern of clinical samples isolated from patients attending or admitted in two health facilities in Kiambu County, Kenya. METHODOLOGY: One hundred and thirty-eight (138) clinical samples were collected from patients attending Thika and Kiambu Level-5 Hospitals. The isolates were obtained using standard bacteriological techniques. Methicillin resistance of Staphylococcus aureus was determined using the cefoxitin disk diffusion test. RESULTS: Out of 138 samples, 54 (39.1%) were found to have Staphylococcus aureus of which 22 (40.7%) were shown to be MRSA using the cefoxitin- based susceptibility test. Antibiotic susceptibility testing using Kirby-Bauer technique was performed on all 54 isolates. The highest sensitivity was found in chloramphenicol 46 (85.2%) and lowest in penicillin-G 8 (14.8%). Multi-Drug Resistance (MDR) was reported in 35 (64.8%) of the 54 isolates of Staphylococcus aureus. All 22 MRSA strains were found to be MDR. CONCLUSIONS: the data obtained revealed that there is presence of MRSA in healthcare settings in Kiambu County, Kenya with varying antibiotic sensitivity patterns as well as multidrug resistance. The findings will help healthcare workers in the county to develop preventive strategy as well as institute policy for antibiotic usage, infection control and surveillance.