Infectious Disorders - Drug Targets (Formerly Current Drug Targets - Infectious Disorders) - Volume 20, Issue 1, 2020

Chronic hepatitis C remains a major public health concern with a prevalence of more than 1% worldwide. Of late, with the discovery of newer drugs, chronic HCV treatment has touched new dimensions. The treatment has progressed from Interferons to Pegylated interferon (Peg IFN) based therapy, with or without ribavirin to treatment with orally active Direct Acting Antivirals (DAA) with Peg IFN and ribavirin and eventually to various combinations of DAA, without IFN. Introduction of newer DAAs has transfigured the treatment of chronic HCV. Chronic HCV patients with advanced liver disease, psychiatric condition, anemia or autoimmune diseases, not eligible for Peg IFN based therapy have a ray of hope now. Amongst all DAAs, nucleoside inhibitors have been the most promising agent. Thus the present review focuses on Sofosbuvir, one of the most effective nucleoside inhibitors; in terms of potency, resistance profile, activity against all genotypes of HCV and adverse effects. FDA approved Sofobuvir for clinical use in 2013. Chemically, it is 2'-deoxy-2'-α-fluoro-β-Cmethyluridine- 5'-triphosphate; a phosphoramidate prodrug that is activated by enzyme present in human liver. It is a highly potent inhibitor of HCV NS5B polymerase. Efficacy of the Sofosbuvir has been established in various phase 2 and phase 3 clinical trials like PROTON, ELECTRON, FUSION, POSITRON etc. Sofosbuvir has a good safety profile with few mild to moderate adverse effects. Evidence reveals that sofosbuvir has substantial impact on the treatment of HCV.

Free radicals are generated in our body by several systems. A balance among free radicals and antioxidants is an important matter for appropriate physiological function. If free radicals become greater than the ability of the body to control them, a case known as oxidative stress appears, as a result of that, a number of human diseases spread in the body. Antioxidants can contribute to facingthis oxidative stress. The present review provides a brief overview of free radicals, oxidative stress, some natural antioxidants and the relationship between them.

Background: Chemotherapy as a science began within the 1st decade of the twentieth century with understanding of the principles of selective toxicity, the particular chemical relationships between microorganism pathogens and medicines, the event of drug resistance, and also the role of combined medical aid. Objectives: This review aims to highlight the characteristics, specifically the pharmacokinetic parameters and the analytical methods reported in literature for the determination of Cefquinome, a fourth generation cephalosporine used to treat Gram-positive and Gram-negative caused infections. Conclusion: Analysis of such drugs, whether used for the treatment of human or animal illness, is essential in understanding the bioavailability and therapeutic control which will ensure their activity and safety.

South Africa is considered the epicenter of HIV/AIDS with a high rate of TB infection as well. Links have been established between treatments of these conditions to ototoxicity. However, no standardized and systematic ototoxicity monitoring exists within the clinical sites where these conditions are treated, with very minimal and adhoc involvement of audiologists as part of the treatment team. With 3.4 million HIV-infected South Africans being reported to have been on antiretroviral drugs by the end of March 2016; with universal coverage being the target, it is important that ototoxicity monitoring becomes part of the treatment plan. The objective of the current paper is to propose an ototoxicity monitoring protocol that can be implemented within this population to ensure that systematic data are collated in order for evidence-based protocols to be adopted within the South African context. Such a protocol will also allow for early identification and intervention of ototoxic hearing loss within this population. Enough evidence exists to support implementation of standardized protocols that will allow for proper, accurate, efficient, and reliable comparisons of data within and between patients; as well as between and within treatment sites – both locally and internationally. It is hoped that implementation of such a monitoring protocol will also have significant implications for the expanded role of the audiologist in the drug development process, affording evidence-based benefit-risk assessments of drugs in the market for this population.

Background: Chronic infection with Hepatitis C virus (HCV) is considered as a major cause for developing liver cirrhosis and hepatocellular carcinoma. A new era in HCV treatment is ongoing using Direct Acting Antiviral activity (DAA). The first approved DAA drug was Sofosbuvir which has a high tolerability and preferable pharmacokinetic profile. Another recently developed drug is Daclatasvir a first-in-class HCV NS5A replication complex inhibitor. Both drugs are administered orally once daily and have potent antiviral activity with wide genotypic coverage. Methods: In the outpatient clinic, one hundred and fifty naïve difficult to treat chronic HCV patients were recruited from Tropical Medicine Department at Fayoum public hospital. A combination of Daclatasvir (60 mg) and Sofosbuvir (400 mg) (DCV/SOF) has been administered for those patients once daily with Ribavirin (1200 mg or 1000 mg based on patients’ weight on two divided doses) over a period of 12 weeks. All patients have been followed up for clinical, laboratory assessment and HCV PCR to detect the efficacy and safety of the therapy. Results: Sustained Virologic Response rate (SVR12) was achieved in the vast majority of patients (90.67%). Cirrhotic patients showed lower SVR compared to non-cirrhotic patients (88.89% vs 90.91%, respectively). Around half of the patients (49.33%) developed adverse events (AEs) during treatment. The most common AEs were headache, fatigue and abdominal pain. Conclusion: The available evidence seems to suggest that combination therapy of (DCV/SOF with RBV) in the treatment of chronic HCV genotype IV naïve difficult to treat patients either cirrhotic or non-cirrhotic is safe and effective. Monitoring for clinical and laboratory hepatic parameters was the basis for these findings.

Introduction: Plasmid-induced quinolone resistance has raised a great concern in the treatment of serious infections worldwide. The aims of this study were to determine the antibiotic susceptibility, the frequency of qepA, aac(6')-Ib and qnr genes by PCR and sequencing, and typing of the resistant isolates using repetitive extragenic palindromic sequence-based PCR (REPPCR) in Pseudomonas aeruginosa isolated from burn wound infections. Methods: In the current cross-sectional study, 149 P. aeruginosa were isolated from the burn wound samples of patients admitted to Motahari hospital in Tehran, Iran, from February to December 2016. The bacterial isolates were identified using standard laboratory methods and their antibiotic susceptibility to quinolones was evaluated using the standard Kirby-Bauer method, according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. The presence of aac(6')-Ib, qepA, qnrA, qnrB4, qnrB and qnrS genes was assessed using PCR and sequencing methods and clonal relationship of the resistant isolates was evaluated using REP-PCR method. Results: All (100%) isolates showed complete resistance to used quinolone compounds in this study. The qnr and qepA genes were not found, but all (100%) isolates were positive for the presence of aac(6')-Ib gene and the sequencing revealed that all (100%) belong to the aac(6')-Ib-cr variant. REP-PCR showed that the studied isolates belonged to three distinct clones of A (77.9%), B (18.1%), and C (4%). Conclusion: The findings of the present study indicated the presence of aac(6')-Ib-cr variant and lack of the contribution of qnr and qepA in the emergence of resistance to quinolones in P. aeruginosa isolated from burn patients. Considering the importance of clonal spread of these resistant isolates and their significant role in the development of clinical infections, especially in patients with burns, more attention should be paid to the prevention of the dissemination of these resistant isolates.

Background: Resistance to antimicrobial agents in Pseudomonas aeruginosa (P. aeruginosa) including carbapenems is a prominent problem in patients. The aim of this study is surveying Metallo-beta-lactamase (MBL)-producing P. aeruginosa isolated from patient specimens with nosocomial and non-nosocomial infections in Kurdistan province, Iran. Methods: In total, 146 Pseudomonas spp. were collected (December 2015 to August 2017). P. aeruginosa isolates were detected by phenotypic and polymerase chain reactions (PCR) of gyrB gene. Combination disk (CD) phenotypic test was used for the identification of MBL-producing strains and PCR was applied for identification of blaIMP and blaVIM genes in P. aeruginosa. Sensitivity and specificity of phenotypic tests were calculated as well. Fisher’s exact test and logistic regression were used for data analysis (p≤0.05). Results: A total of 134 (91.78%) and 133 (91.09%) P. aeruginosa were detected using PCR and the phenotypic test, respectively. Fifty-six (41.79%) clinical isolates were isolated from patients with nosocomial infection. CD test proved that 67 out of 134 (50%) P. aeruginosa isolates were positive for MBL, of which 11 (8.20%) carried blaIMP gene. No significant relationship was found between MBL-producing P. aeruginosa and blaIMP genes; as well as between MBL-producing P. aeruginosa and blaIMP genes with age, sex, city of residence, inpatient/outpatient and specimen's type (p≥0.05). Conclusion: Presence of MBL-producing P. aeruginosa strains and blaIMP genes were proved in this study; thus more precaution should be taken in the administration of carbapenem antibiotics to patients.

Background: Tissue destruction can be measured by the level of lipid peroxidation (LP) end products. Since free radicals are very reactive with low survival time, the level of free radicals and oxidative stress activity are measured indirectly by tissue damage end product assessment, i.e. Malondialdehyde (MDA) that is a final end product of LP. Objective: The aim of this study was to evaluate salivary MDA level as an indicator of oxidative stress; in caries-active and caries-free students. Methods: A total of 100 male and female students, 15-17 years of age, participated in this casecontrol study. Five mL of whole saliva was obtained. Salivary MDA level was measured spectrophotometrically. Statistical comparisons were performed with Student’s t-test, using SPSS 13. Results: Salivary MDA level was significantly higher in the caries-active group compared to the control caries-free group. MDA was also slightly lower in males. Conclusion: Higher MDA level might indicate caries-induced oxidative stress. In this study there was a relationship between salivary MDA level and dental caries. Therefore oxidative stress suppression might prevent caries initiation and progression.

Background: The need for suitable antibacterial agents effective against Multi-drug resistant Gram-negative bacteria is acknowledged globally. The present study was designed to evaluate the possible antibacterial potential of an extracted compound from edible flowers of Moringa oleifera. Methods: Five different solvents were used for preparing dried flower extracts. The most effective extract was subjected to fractionation and further isolation of the active compound with the highest antibacterial effect was obtained using TLC, Column Chromatography and reverse phase- HPLC. Approaches were made for characterization of the isolated compound using FTIR, NMR and Mass spectrometry. Antibacterial activity was evaluated according to the CLSI guidelines. Results: One fraction of aqueous acetic acid extract of M. oleifera flower was found highly effective and more potent than conventional antibiotics of different classes against Multi-drug resistant Gram-negative bacilli (MDR-GNB) when compared. The phytochemical analysis of the isolated compound revealed the presence of hydrogen-bonded amine and hydroxyl groups attributable to unsaturated amides. Conclusion: The present study provided data indicating a potential for use of the flowers extract of M. oleifera in the fight against infections caused by lethal MDR-GNB. Recommendations: Aqueous acetic acid flower extract of M. oleifera is effective, in-vitro, against Gram-negative bacilli. This finding may open a scope in pharmaceutics for the development of new classes of antibiotics.

Background: Stavudine is an antiretroviral therapy with so many side effects and has a short half-life of 1.5 h. It degrades to thymine under hydrolytic, oxidative and photolytic conditions hence has major formulation challenges. Objectives: To formulate sustained release lipid based stavudine and to study the properties of the formulations by in vitro and in vivo methods. Methods: Stavudine tablets were formulated by moulding using validated tablets moulds. The carrier used were solidified reverse micellar solution (SRMS) made up of varying ratios of hydrogenated palm oil and Phospholipid admixtures. Evaluation tests were carried out on the tablets using both Pharmacopoeial and non Pharmacopoeial test. Drug release was studied in both simulated gastric fluid (SGF, pH 1.2) and simulated intestinal fluid (SIF, pH 7.2). In vivo release was studied using Wistar rats. Results: The results showed that stavudine tablets exhibited weight range of 372 ± 0.14 to 386 ± 0.52 mg, friability ranged from 0.00 to 0.13 % and hardness ranged from 4.27 ± 0.25 to 5.30 ± 0.21 Kgf. Tablets formulated with SRMS 1:2 had erosion time range of 60.80 ± 1.23 to 87.90 ± 2.33 min and was affected significantly by the presence of Poloxamer 188 (p < 0.05). The formulations exhibited T100 % at 10 to13 h in SIF. Stavudine tablets showed the area under the curve (AUC) of 854.0 μg/h/ml, significantly higher than the AUC of the reference (p < 0.05). Conclusion: Stavudine SRMS-based tablets had good stability and sustained release properties. Formulations containing 1 % Poloxamer 188 exhibited enhanced in vivo absorption and hence could be used once daily in order to enhance the bioavailability of this drug.

Background: Side effects and toxicity have posed a threat to the positive contribution of Antiretroviral Therapy (ART) in the management of human immunodeficiency virus (HIV) infection and Acquired Immune Deficiency Syndrome (AIDS). Symptoms of mitochondrial toxicity including myopathy, pancreatitis, hyperlipidaemia and lactic acidosis are found among HIVinfected patients on ART. To date, there is not a reliable biomarker for monitoring ART-related mitochondrial toxicity. Plasma level of Cytochrome c (Cyt-c) has been proposed as a potential biomarker for ART-related toxicity due to its strong association with apoptosis. Objective: The present study assessed toxicity and level of plasma Cyt-c among HIV-infected patients receiving ART in Ghana. Methods: A total of eighty (80) HIV patients were recruited into the study. Demographic data were obtained from personal interview and medical records. Plasma samples were screened for toxicity from sixty (60) participants due to limited resources, and plasma Cyt-c levels were determined using ELISA. Data were analyzed using Stata version 13. Results: Out of the 60 participants, 11 (18.3%) were found with symptoms of myopathy, 12 (20%) with pancreatitis, 21 (35%) with hyperlipidaemia and 36 (60%) with at least one of the symptoms. The concentration of plasma Cyt-c was higher (0.122 ng/ml) in patients with toxicity than in those without toxicity (0.05 ng/ml), though the difference was not statistically significant (p = 0.148). There was a weak correlation between plasma Cyt-c level and duration of ART (Spearman rho = 0.02, p = 0.89). Conclusion: This study, therefore, demonstrated a high prevalence of ART-related toxicity and high levels of Cyt-c in HIV-infected patients in support of the argument that plasma Cyt-c levels are potential biomarkers for determining ART-related toxicity in HIV patients.

Background: Trichomoniasis is known as a common venereal disease. It is estimated that 180 million people in the world are infected with this disease. The present study was conducted to estimate the prevalence of (Trichomonas vaginalis) T. vaginalis among women who were referred to the central laboratory in Ilam. Methods: In this cross-sectional study, 481 women with suspicious symptoms of trichomoniasis were selected during the first six months of 2015 in the central laboratory and Shahid Mostafa laboratory in Ilam, Iran. All patients were referred to the labs by gynecologists. Sterile swabs were used to collect direct smears. The results and questionnaire data were entered into SPSS version 16 and were analyzed using chi-square test and Fisher's exact test. Results: Direct smear of T. vaginalis demonstrated seven positive cases (1.5%). The highest and the lowest percentages of T. vaginalis infection in women were related to the 45-50 and 20-30 years age groups, respectively. Illiterate women had the highest percentage of infection. No significant relationship was found between the level of education and trichomoniasis infection in women (p = 0.085). The highest infection rate was associated with the use of ectopic contraceptive methods (condoms). Conclusion: The prevalence of T. vaginalis was low among women in Ilam but was high among women who have used tubal ligation and condom to prevent pregnancy. Therefore, more attention is required from healthcare centers for appropriate education to women about the proper use of protective equipment.

Background: Brucellosis, a major health problem in developing countries, is a multisystem infection with a broad spectrum of clinical manifestations. Hematological complications, ranging from an intravascular coagulopathy to mild homeostasis disorders (such as gammopathy), have been reported in brucella infection. These signs and symptoms may lead to misdiagnosis of brucellosis with other hematological diseases. Case: A 65-year-old male whose occupation was shepherding was referred to our hospital as a known case of multiple myeloma with continuous fever, muscle weakness, and night sweating after taking 2 courses of chemotherapy. The laboratory diagnosis of multiple myeloma had been based on the observation of a high percent of plasma cells in the bone marrow aspiration. At follow- up, the result of patient's fever workup, with 2 sets of blood cultures, was positive for Brucella melitensis. Isolated brucella was confirmed as B. melitensis by 16S rRNA sequencing. Brucellosis serologic test was performed by agglutination test and positive results were obtained. The patient was discharged with the cessation of fever and general improvement after the end of the parental treatment phase of brucella bacteremia. Conclusions: Brucella infection may cause a severe disease, mimicking a primary hematological disease, which could complicate the correct diagnosis. In brucellosis cases, due to the wide range of symptoms, in addition to cultivation and serological methods, molecular methods should also be used to prevent inappropriate diagnosis and additional costs

Background: Burkholderia cepacia complex is widespread in the environment and has been recognized as a cause of opportunistic pulmonary infections, particularly in patients with Cystic Fibrosis (CF). The natural ecology of the bacteria as part of plant growth-promoting rhizosphere provides stark contrast to its infectious potential. Its preponderance as a nosocomial pathogen may be due to its ability to survive in antiseptic solutions, contaminate equipments and intrinsic antimicrobial resistance. Case: An elderly, diabetic male was evaluated for hemoptysis, fever and cough. Chest computed tomography showed a thick walled cavity in the left lung and hilar lymphadenopathy. Sputum examination showed Gram negative bacilli and no acid fast bacilli. Sputum culture yielded growth of non-fermentative Gram negative bacilli on two occasions, but blood culture was sterile. The isolate was identified as B. cepacia by Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS). The patient’s general condition remained poor and in spite of initiation of antibiotics, the patient expired after an episode of massive hemoptysis. Conclusion: This report raises concerns regarding the spread and severity of B. cepacia infection in non-compromised patients in the community and the need to suspect and identify it. Since the organism is inherently resistant to antipseudomonal penicillins, aminoglycosides and polymyxin B, differentiation from Pseudomonas spp. and determining antimicrobial susceptibility is paramount for treatment.