Delayed seropositivity is associated with lower levels of SARS-CoV-2 antibody levels in patients with mild to moderate COVID-19.

BACKGROUND: Patients with COVID-19 can develop a range of immune responses, including variations in the onset and magnitude of antibody formation. The aim of this study was to investigate whether SARS-CoV-2 antibody levels vary in patients with mild to moderate COVID-19 in relation to the onset (days) of their post-symptom seropositivity and to explore host factors that may affect antibody production METHODS: This was a prospective, multiple measurements study involving 92 PCR-confirmed patients with mild to moderate COVID-19. Antibody testing for anti-nucleocapsid (anti-NP) and spike proteins (anti-S) was performed using ELISA tests. Serum samples were collected over a period of 55 days from symptom onset of COVID-19 infection, and repeated as necessary until they turned positive. RESULTS: No significant differences were found between the positivity rates of anti-S or anti-NP regarding any clinical symptom (p > 0.05). The majority of patients who tested positive for anti-NP and anti-S showed early seropositivity (within 15 days of symptom onset) (75.9% for anti-NP and 82.6% for anti-S). Younger patients, those without chronic diseases, and non-healthcare workers had the highest percentage of seroconversion after day 35 post-symptom onset (p = 0.002, 0.028, and 0.036, respectively), while older patients and those with chronic diseases had earlier seropositivity and higher anti-NP levels (p = 0.003 and 0.06, respectively). Significantly higher anti-S ratios were found among older (p = 0.004), male (p = 0.015), and anemic patients (p = 0.02). A significant correlation was found between both antibodies (p = 0.001). At the end of the study, the cumulative seroconversion rate for both antibodies was almost 99%. CONCLUSIONS: Some COVID-19 patients may exhibit delayed and weak immune responses, while elderly, anemic patients and those with chronic diseases may show earlier and higher antibody responses.

Lectins purified from medicinal and edible mushrooms: Insights into their antiviral activity against pathogenic viruses.

For thousands of years, fungi have been a valuable and promising source of therapeutic agents for treatment of various diseases. Mushroom is a macrofungus which has been cultivated worldwide for its nutritional value and medicinal applications. Several bioactive molecules were extracted from mushroom such as polysaccharides, lectins and terpenoids. Lectins are carbohydrate-binding proteins with non-immunologic origin. Lectins were classified according to their structure, origin and sugar specificity. This protein has different binding specificity with surface glycan moiety which determines its activity and therapeutic applications. A wide range of medicinal activities such as antitumor, antiviral, antimicrobial, immunomodulatory and antidiabetic were reported from sugar-binding proteins. However, glycan-binding protein from mushroom is not well explored as antiviral agent. The discovery of novel antiviral agents is a public health emergency to overcome the current pandemic and be ready for the upcoming viral pandemics. The mechanism of action of lectin against viruses targets numerous steps in viral life cycle such as viral attachment, entry and replication. This review described the history, classification, purification techniques, structure-function relationship and different therapeutic applications of mushroom lectin. In addition, we focus on the antiviral activity, purification and physicochemical characteristics of some mushroom lectins.

Metallo-Beta-Lactamase Producing Pseudomonas aeruginosa in a Healthcare Setting in Alexandria, Egypt.

Pseudomonas aeruginosa has emerged as a major healthcare associated pathogen that creates a serious public health disaster in both developing and developed countries. In this work we aimed at studying the occurrence of metallo-beta-lactamase (MBL) producing P. aeruginosa in a healthcare setting in Alexandria, Egypt. This cross sectional study included 1583 clinical samples that were collected from patients admitted to Alexandria University Students' Hospital. P. aeruginosa isolates were identified using standard microbiological methods and were tested for their antimicrobial susceptibility patterns using single disc diffusion method according to the Clinical and Laboratory Standards Institute recommendations. Thirty P. aeruginosa isolates were randomly selected and tested for their MBL production by both phenotypic and genotypic methods. Diagnostic Epsilometer test was done to detect metallo-beta-lactamase enzyme producers and polymerase chain reaction test was done to detect imipenemase (IMP), Verona integron-encoded (VIM) and Sao Paulo metallo-beta-lactamase (IMP) encoding genes. Of the 1583 clinical samples, 175 (11.3%) P. aeruginosa isolates were identified. All the 30 (100%) selected P. aeruginosa isolates that were tested for MBL production by Epsilometer test were found to be positive; where 19 (63.3%) revealed blaSPM gene and 11 (36.7%) had blaIMP gene. blaVIM gene was not detected in any of the tested isolates. Isolates of MBL producing P. aeruginosa were highly susceptible to polymyxin B 26 (86.7%) and highly resistant to amikacin 26 (86.7%). MBL producers were detected phenotypically by Epsilometer test in both carbapenem susceptible and resistant P. aeruginosa isolates. blaSPM was the most commonly detected MBL gene in P. aeruginosa isolates.

Epstein-Barr virus in multiple sclerosis.

BACKGROUND/OBJECTIVES: Multiple sclerosis (MS) is an inflammatory disorder of the central nervous system. Many diseases are associated with Epstein-Barr virus (EBV) infection, such as infectious mononucleosis and many types of malignancies, and it is thought to be related to some diseases of autoimmune origin, such as rheumatoid arthritis, systemic lupus erythematosis, and others. The present study aimed to assess EBV in patients with MS. PATIENTS AND METHODS: This case-control study was conducted from October 2012 to September 2013 on 75 MS patients and non-MS controls. Both were tested quantitatively for immunoglobulin G (IgG) antibodies against Epstein-Barr nuclear antigen-1 (EBNA1) and viral capsid antigen (VCA) using the enzyme linked immunosorbent assay technique. RESULTS: Seventy MS patients (93.3%) were positive for EBNA1 IgG compared with 68 controls (90.7%). In MS patients, the mean EBNA1 IgG serum level was 310.91 (±131.05) U/ml; meanwhile, among controls the mean serum EBNA IgG level was 177.81 (±104.98) U/ml.All patients with MS were positive for VCA IgG, whereas only 60 (80.0%) controls were positive. In the MS group, the VCA IgG mean level was 302.19 (±152.11) U/ml compared with 167.94 (±111.79) U/ml in controls. The differences in the serum levels of both markers between the two groups were statistically significant (P<0.001). CONCLUSION AND RECOMMENDATIONS: EBV proved to have a unique immunological pattern in MS patients when compared with non-MS controls. Further studies for more confirmation of the relation between EBV and MS on a large scale are recommended.

Performance of a rapid test versus real-time PCR for diagnosis of H1N1 swine flu.

BACKGROUND AND OBJECTIVE: For effective control and treatment of swine influenza, rapid and cost-effective diagnosis is important. Although the gold-standard method for the diagnosis of influenza virus is culture isolation, it is not routinely used in outpatient settings because of the cost and the time needed to complete the assay. This has led to the development of an array of rapid influenza diagnostic tests. The aim of this study was to compare between the performance of CerTest Swine Flu card and RT-PCR in the detection of H1N1 infection. MATERIALS AND METHODS: This study included 40 clinically suspected cases of H1N1. Nasal and throat swabs were collected from patients, placed in viral transport medium, and kept at 4°C until being tested on the same day for the presence of H1N1, using the CerTest Swine Flu test and real-time PCR. RESULTS: Of these 40 suspected cases, seven (17.5%) were found to be positive by the PCR technique, whereas 33 (82.5%) were found to be negative. Of the seven positive cases by the PCR technique, six were found to be positive by the rapid test, and thus the sensitivity of the rapid test was found to be 85.7%, and the specificity was 100%. CONCLUSION: CerTest Swine Flu card rapid test was found to have reliable sensitivity and specificity compared with the gold-standard RT-PCR.

Screening for the hepatitis C virus in some dental clinics in Alexandria, Egypt.

BACKGROUND/OBJECTIVES: Individuals can be exposed to the hepatitis C virus (HCV) infection through inadequately or improperly sterilized medical or dental equipment. The aim of this study was to detect HCV RNA in the dental setting in Alexandria, Egypt. MATERIALS AND METHODS: The study included 100 samples collected from five dental clinics (A-E) in Alexandria. The samples were collected from critical, semicritical, and noncritical instruments during different periods of the day (morning, mid-day, end of the day). Samples were subjected to a reverse transcriptase-PCR for the detection of HCV RNA. RESULTS: HCV RNA was detected in 18% (18 out of 100) of the instrument samples tested. Two positive HCV RNA samples were collected from semicritical instruments in clinic B, whereas 16 positive HCV RNA samples were collected from clinic D (eight samples from critical, six samples from semicritical, and two samples from noncritical instruments). There was a statistically significant difference between clinics B and D in terms of the samples collected in the morning and those collected at the end of the day. CONCLUSION AND RECOMMENDATIONS: HCV RNA as detected by PCR was found in a considerable percent of instruments' samples (18%). Most of the positive HCV RNA samples (16 out of 18 samples) obtained from instruments were among those collected from clinic D. This clinic used only glutaraldehyde as a method of sterilization. Therefore, proper infection control measures, including sterilization and disinfection should be strictly adopted.

Role of occult hepatitis B virus in chronic hepatitis C patients with flare of liver enzymes.

BACKGROUND: Occult HBV infection is defined by detection of HBV DNA in the serum or liver tissue of patients who test negative for HBsAg. The prevalence of occult HBV is higher in hepatitis C virus (HCV) positive patients than HCV negative patients and may have an impact on their clinical outcome. In this study, we evaluated the role of occult hepatitis B virus infection in chronic hepatitis C patients with ALT flare. METHODS: Sixty HBsAg negative patients with chronic hepatitis C virus infection were included. Patients were divided into 2 groups according to their ALT level: 30 patients with normal or slightly high ALT and 30 patients with ALT flare (≥ 5 times normal values). Patients in both groups were examined for the detection of anti-HBs, anti-HBc IgM, and anti-HBc IgG. HBV DNA was detected using semi-nested PCR technique. RESULTS: In patients with normal or slightly high ALT, HBV DNA was detected in 4 (13.3%) patients, while in those with ALT flare, HBV DNA was detected in 19 (63.3%) patients (p<0.001). No association was found between the presence of HBV DNA and various serology markers of HBV infection. CONCLUSION: Presence of occult hepatitis B, with its added deleterious effect, must always be considered in chronic hepatitis C patients especially those with flare in liver enzymes; HBsAg should not be used alone for the diagnosis of HBV infection.

Evaluation of Interleukin-18 as a Non Invasive Marker of Liver Fibrosis among Chronic Hepatitis C Virus Patients.

BACKGROUND: The World Health Organization has declared hepatitis C a global health problem, with approximately 3% of the world's population (roughly 170-200 million people) infected with hepatitis C virus (HCV). In Egypt, Chronic hepatitis C is the main cause of liver cirrhosis and liver cancer. Liver biopsy is currently the gold standard method for ascertaining the presence of cirrhosis, and scoring the severity of necroinflammation and fibrosis, but it is invasive, expensive and associated with rare but serious complications. There has been increasing interest in noninvasive assessment of liver fibrosis by the use of surrogate serum markers; one of them is interleukin-18 (IL-18). OBJECTIVES: The aim of this study was the estimation of the levels of interleukin-18 in chronic hepatitis C patients and comparing between IL-18 levels and results of liver biopsy, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. MATERIAL AND METHODS: It included fifty chronic viral hepatitis C patients who were subjected to liver biopsy as well as fifty healthy blood donors as a control group. Sera were tested for estimation of ALT and AST levels and were subjected to enzyme-linked immunosorbent assay (ELISA) for determination of IL-18 levels. RESULTS: The mean level of IL-18 was significantly higher in chronic hepatitis C patients (347.22pg/ml) compared to the controls (209.61pg/ml), and there was significant relation between levels of IL-18 and the stage of liver fibrosis. CONCLUSION: IL-18 could be used as an additional non invasive marker for monitoring the degree of liver fibrosis in chronic hepatitis C patients.

Microbial study of meningitis and encephalitis cases.

Meningitis and/or encephalitis can pose a serious public health problem especially during outbreaks. A rapid and accurate diagnosis is important for effective earlier treatment. This study aimed to identify the possible microbial causes of meningitis and/or encephalitis cases. CSF and serum samples were collected from 322 patients who had signs and symptoms suggestive of meningitis and/or encephalitis. Out of 250 cases with confirmed clinical diagnosis, 83 (33.2%) were definitely diagnosed as bacterial meningitis and/or encephalitis cases (by using CSF culture, biochemical tests, latex agglutination test, and CSF stain), 17 (6.8%) were definitely diagnosed as having viral causes ( by viral isolation on tissue culture, PCR and ELISA), and one (0.4%) was diagnosed as fungal meningitis case (by India ink stain, culture, and biochemical tests). Also, there was one encephalitis case with positive serum ELISA IgM antibodies against Sandfly scilian virus. N. meningitidis, S. pneumonia and M. tuberculosis were the most frequently detected bacterial agents, while Enteroviruses, herpes simplex viruses and varicella zoster viruses were the most common viral agents encountered. Further studies are needed to assess the role of different microbial agents in CNS infections and their effective methods of diagnosis.

Fungal Infection among Patients with Some Hematopoietic Disorders.

With the increasing number of immune compromised patients suffering from hematological disorders, invasive fungal infections have emerged as a major cause of morbidity and mortality among these patients. This study evaluated the use of conventional blood culture and PCR techniques in the isolation and identification of fungi from patients with different hematopoietic disorders. Ninety blood samples were tested by both techniques, conventional blood culture detected fungal infections in only five (5.6%) samples, which were further identified to be of Candida spp. While PCR technique detected fungal infections in 56 (62.2%) samples, which were further subjected to nested PCR technique giving final identification of Candida spp. infections in 36 (40%) samples and Aspergillus spp. in 16 (17.8) samples. The sensitivity of PCR technique was 100% and the specificity ranged from 40% to 100%. Thus, the use of nested PCR technique was an efficient and sensitive method for detection of invasive fungal infections among patients with hematopoietic disorders.