Isolation and Detection of Drug-Resistant Bacterial Pathogens in Postoperative Wound Infections at a Tertiary Care Hospital in Saudi Arabia.

Background: Surgical site infections (SSIs), especially when caused by multidrug-resistant (MDR) bacteria, are a major healthcare concern worldwide. For optimal treatment and prevention of antimicrobial resistance, it is important for clinicians to be aware of local drug-resistant bacterial pathogens that cause SSIs. Objective: To determine the frequency patterns of drug-resistant bacterial strains causing SSIs at a tertiary care hospital in Saudi Arabia. Methods: This retrospective study was conducted at the Microbiology laboratory of Al-Noor Specialist Hospital, Makkah, Saudi Arabia, and included wound swab samples from all cases of SSI between January 01, 2017, and December 31, 2021. The swabs were processed for the identification of bacterial strains and their resistance pattern to antibiotics according to the Clinical and Laboratory Standards Institute. Results: A total of 5409 wound swabs were analyzed, of which 3604 samples (66.6%) were from male. Most samples were from the Department of Surgery (43.3%). A total of 14 bacterial strains were isolated, of which 9 were Gram-negative bacteria. The most common isolates were Klebsiella pneumoniae, followed by Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococci (VRE), and vancomycin-resistant S. aureus (VRSA). In terms of MDR in 2021, the highest rate of carbapenem-resistance was in A. baumannii (97%). MDR was as follows: A. baumannii, 97%; K. pneumoniae, 81%; E. coli, 71%; MRSA, 60%; P. aeruginosa, 33%; VRE, 22%; and VRSA, 2%. Conclusion: This study showed that in the city of Makkah, Saudi Arabia, the rates of MDR bacteria are high, with the majority being Gram-negative.

Preparation and biological evaluation of metronidazole derivatives with monoterpenes and eugenol.

Two series of metronidazole derivatives (ester derivatives and ether derivatives) were prepared reacting metronidazole and its acetic acid oxidized form with menthol, thymol, carvacrol, and eugenol. Both series of compounds were tested in vitro against two strains of Helicobacter pylori (the ATCC 26695 and P12), and one strain of Clostridium (Clostridium perfringens). Most of the prepared compounds showed biological activity against the targeted bacteria. Compound 11 was highly active against all tested bacterial strains, especially against P12 with IC50 0.0011 µM/ml. Compound 6 was highly active against C. perfringens with MIC 0.0094 nM/ml. Viability test was conducted for compound 11 to test its selectivity for normal human fetal lung fibroblasts (MRC5), and it was found to be non-toxic with IC50 more than 50 µM/ml.

Berberine nanoparticles with enhanced in vitro bioavailability: characterization and antimicrobial activity.

BACKGROUND: Berberine is an isoquinoline alkaloid widely used in Ayurveda and traditional Chinese medicine to treat illnesses such as hypertension and inflammatory conditions, and as an anticancer and hepato-protective agent. Berberine has low oral bioavailability due to poor aqueous solubility and insufficient dissolution rate, which can reduce the efficacy of drugs taken orally. In this study, evaporative precipitation of nanosuspension (EPN) and anti-solvent precipitation with a syringe pump (APSP) were used to address the problems of solubility, dissolution rate and bioavailability of berberine. METHODS: Semi-crystalline nanoparticles (NPs) of 90-110 nm diameter for APSP and 65-75 nm diameter for EPN were prepared and then characterized using differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRD). Thereafter, drug content solubility and dissolution studies were undertaken. Berberine and its NPs were evaluated for their antibacterial activity. RESULTS: The results indicate that the NPs have significantly increased solubility and dissolution rate due to conversion of the crystalline structure to a semi-crystalline form. CONCLUSION: Berberine NPs produced by both APSP and EPN methods have shown promising activities against Gram-positive and Gram-negative bacteria, and yeasts, with NPs prepared through the EPN method showing superior results compared to those made with the APSP method and the unprocessed drug.

Dexibuprofen nanocrystals with improved therapeutic performance: fabrication, characterization, in silico modeling, and in vivo evaluation.

BACKGROUND: The aim of this study was to prepare and evaluate the impact of polymers on fabricating stable dexibuprofen (Dexi) nanocrystals with enhanced therapeutic potential, using a low energy, anti-solvent precipitation method coupled with molecular modelling approach. METHODS: Dexi nanocrystals were prepared using antisolvent precipitation with syringe pump. Crystallinity of the processed Dexi particles was confirmed using differential scanning calorimetry and powdered X-ray diffraction and transmission electron microscopy. Dissolution of Dexi nanocrystals was compared with raw Dexi and marketed tablets. Molecular modelling study was coupled with experimental studies to rationalise the appropriate polymers for stable Dexi nanocrystals. Antinociceptive study was carried out using balb mice. RESULTS: Combinations of hydroxypropyl methylcellulose (HPMC)-polyvinyl pyrrolidone (PVP) and HPMC-Eudragit (EUD) were shown to be very effective in producing stable Dexi nanocrystals with particle sizes of 85.0±2.5 nm and 90±3.0 nm, and polydispersity of 0.179±0.01, 0.182±0.02, respectively. The stability studies conducted for 90 days demonstrated that nanocrystals stored at 2°C-8°C and 25°C were more stable than those at 40°C. The maximum recovery of Dexi nanocrystals was observed from the formulations using the combination of HPMC-PVP and HPMC-EUD, which equated to 98% and 94% of the nominal active drug content respectively. The saturation solubility of the Dexi nanocrystals was substantially increased to 270.0±3.5 µg/mL compared to the raw Dexi in water (51.0±2.0 µg/mL) and stabilizer solution (92.0±3.0 µg/mL). Enhanced dissolution rate (P<0.05) was observed for the Dexi nanocrystals compared to the unprocessed drug substance and marketed tablets. Dexi nanocrystals produced the analgesic effect at much lower doses (5 mg/kg) than that of control standard, diclofenac sodium (20 mg/kg) and Dexi counterparts (40 mg/kg). CONCLUSION: HPMC-PVP and HPMC-EUD were found the best polymer combination to stabilise Dexi nanocrystals. The Dexi nanocrystals exhibited significant dissolution, solubility and analgesic effect compared to the raw Dexi and the control standard diclofenac sodium.

In vitro inhibitory analysis of consensus siRNAs against NS3 gene of hepatitis C virus 1a genotype.

OBJECTIVE: To explore inhibitory effects of genome-specific, chemically synthesized siRNAs (small interference RNA) against NS3 gene of hepatitis C virus (HCV) 1a genotype in stable Huh-7 (human hepatoma) cells as well as against viral replication in serum-inoculated Huh-7 cells. METHODS: Stable Huh-7 cells persistently expressing NS3 gene were produced under antibiotic gentamycin (G418) selection. The cell clones resistant to 1000 µg antibiotic concentration (G418) were picked as stable cell clones. The NS3 gene expression in stable cell clone was confirmed by RT-PCR and Western blotting. siRNA cell cytotoxicity was determined by MTT cell proliferation assay. Stable cell lines were transfected with sequence specific siRNAs and their inhibitory effects were determined by RT-PCR, real-time PCR and Western blotting. The viral replication inhibition by siRNAs in serum inoculated Huh-7 cells was determined by real-time PCR. RESULTS: RT-PCR and Western blot analysis confirmed NS3 gene and protein expression in stable cell lines on day 10, 20 and 30 post transfection. MTT cell proliferation assay revealed that at most concentrated dose tested (50 nmol/L), siRNA had no cytotoxic effects on Huh-7 cells and cell proliferation remained unaffected. As demonstrated by the siRNA time-dependent inhibitory analysis, siRNA NS3-is44 showed maximum inhibition of NS3 gene in stable Huh-7 cell clones at 24 (80%, P = 0.013) and 48 h (75%, P = 0.002) post transfection. The impact of siRNAs on virus replication in serum inoculated Huh-7 cells also demonstrated significant decrease in viral copy number, where siRNA NS3-is44 exhibited 70% (P < 0.05) viral RNA reduction as compared to NS3-is33, which showed a 64% (P < 0.05) decrease in viral copy number. siRNA synergism (NS3-is33 + NS3-is44) decreased viral load by 84% (P < 0.05) as compared to individual inhibition by each siRNA (i.e., 64%-70% (P < 0.05)) in serum-inoculated cells. Synthetic siRNAs mixture (NS5B-is88 + NS3-is33) targeting different region of HCV genome (NS5B and NS3) also decreased HCV viral load by 85% (P < 0.05) as compared to siRNA inhibitory effects alone (70% and 64% respectively, P < 0.05). CONCLUSIONS: siRNAs directed against NS3 gene significantly decreased mRNA and protein expression in stable cell clones. Viral replication was also vividly decreased in serum infected Huh-7 cells. Stable Huh-7 cells expressing NS3 gene is helpful to develop anti-hepatitis C drug screening assays. siRNA therapeutic potential along with other anti-HCV agents can be considered against hepatitis C.

Risk factors associated with multi-drug-resistant Acinetobacter baumannii nosocomial infections at a tertiary care hospital in Makkah, Saudi Arabia - a matched case-control study.

Objective To determine risk factors for multi-drug-resistant Acinetobacter baumannii (MDR-AB) nosocomial infections in intensive care units in a tertiary care hospital, Makkah, Saudi Arabia. Methods We performed a hospital-based, matched case-control study in patients who were admitted to Al Noor Specialist Hospital between 1 January 2012 and 31 August 2012. The study included cases of A. baumannii nosocomial infection and controls without infection. Controls were matched to cases by age and ward of admission. Results The most frequent site of infection was the respiratory tract (77.3%). Susceptibility to antimicrobial MDR-AB was 92.0% for ceftazidime and ciprofloxacin, while it was 83.3% for imipenem, 83.0% for trimethoprim, 79.0% for amikacin, and 72.7% for gentamicin. Multiple logistic regression of risk factors showed that immunosuppression (OR = 2.9; 95% CI 1.5-5.6; p = 0.002), clinical outcome (OR = 0.4; 95% CI 0.3-0.9; p = 0.01), invasive procedures (OR = 7.9; 95% CI 1.8-34.2; p = 0.002), a central venous catheter (OR = 2.9; 95% CI 1.5-5.6; p = 0.000), and an endotracheal tube (OR = 3.4; 95% CI 1.6-7.3; p = 0.001) were associated with MDR-AB. Conclusions Acinetobacter nosocomial infections are associated with admission to the ICU (Intensive care unit) and exposure to invasive procedures.

Fabrication, characterization and in vitro evaluation of silibinin nanoparticles: an attempt to enhance its oral bioavailability.

BACKGROUND: Silibinin has gained in importance in the past few decades as a hepatoprotector and is used widely as oral therapy for toxic liver damage, liver cirrhosis, and chronic inflammatory liver diseases, as well as for the treatment of different types of cancers. Unfortunately, it has low aqueous solubility and inadequate dissolution, which results in low oral bioavailability. MATERIALS AND METHODS: In this study, nanoparticles (NPs) of silibinin, which is a hydrophobic drug, were manufactured using two cost-effective methods. Antisolvent precipitation with a syringe pump (APSP) and evaporative precipitation of nanosuspension (EPN) were used. The prepared NPs were characterized using different analytical techniques such as scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X-ray powder diffractometry (XRD) and were sifted for their bioavailability through in vitro dissolution and solubility studies. Moreover, the prepared NPs were evaluated for antimicrobial activity against a battery of bacteria and yeast. RESULTS: DSC and XRD studies indicated that the prepared NPs were amorphous in nature, with more solubility and dissolution compared to the crystalline form of this drug. NPs prepared through the EPN method had better results than those prepared using the APSP method. Antimicrobial activities of the NPs were improved compared to the unprocessed drugs, while having comparable activities to standard antimicrobial drugs. CONCLUSION: Results indicate that the NPs have significantly increased solubility, dissolution rate, and antimicrobial activities due to the conversion of crystalline structure into amorphous form.

Effects of Luteolin and Quercetin in Combination with Some Conventional Antibiotics against Methicillin-Resistant Staphylococcus aureus.

The present study was designed to evaluate the effects of flavonoids luteolin (L) and quercetin + luteolin (Q + L) in combination with commonly used antibacterial agents against methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates and S. aureus (ATCC 43300). Minimum inhibitory concentrations (MICs) of L and Q + L, as well as the MICs of flavonoids in combination with antibiotics were determined and results showed an increased activity of flavonoids with antibiotics. The synergistic, additive, or antagonistic relationships between flavonoids (L and Q + L) and antibiotics were also evaluated, and additive and synergistic effects were observed for some antibiotic + flavonoid combinations. In addition, some combinations were also found to damage the bacterial cytoplasmic membrane, as assessed through potassium leakage assay. The effects of flavonoids and flavonoids + antibiotics on mecA gene mutations were also tested, and no functional variation was detected in the coding region.

Acute rhinosinusitis during Hajj season 2014: Prevalence of bacterial infection and patterns of antimicrobial susceptibility.

BACKGROUND: The presence of large number of pilgrims during Hajj in Makkah region increases the risk of respiratory diseases. In this study, we aimed to assess the bacteriology of acute rhinosinusitis (ARS) during Hajj season and to demonstrate the antimicrobial susceptibility patterns that should guide the clinicians towards more appropriate antibiotic use. METHODS: Patients with ARS presenting during Hajj season of 2014 were prospectively enrolled. According to EPOS2012 criteria. Sampling of sinus secretions was performed from the middle meatus adjacent to the maxillary sinus ostium via endoscopic guidance. Over all, the study has covered all ENT, emergency and outpatient departments in Hajj. RESULTS: Two hundred and twenty six patients with ARS were enrolled in the study. Pathogenic bacteria were identified in 93 (41.2%) patients. Of the 93 patients with bacterial ARS, Staphylococcus aureus was isolated in 46 (49.5%) patients, out of which 13 (28.3%) were methicillin-resistant Staphylococcus aureus (MRSA).The second most common group of bacterial isolates was Enterobacteriaceae such as Escherichia coli, and various Klebsiella species. Antibiotic sensitivity showed that methicillin-sensitive Staphylococcus aureus (MSSA) was also sensitive to cephalosporins, quinolones and clindamycin, while exhibiting relatively less sensitivity rates to amoxicillin-clavulinic acid and macrolides. CONCLUSION: Our study demonstrates the importance of assessing the bacteriology of ARS to help implement guidelines for proper treatment and prevention protocols during Hajj season.

INCIDENTAL PARASITIC INFECTIONS IN SURGICALLY REMOVED APPENDICES: A RETROSPECTIVE ANALYSIS.

Numerous parasitic infections can cause inflammation of the appendix and can mimic appendicitis clinically. The diagnosis is generally achieved only after surgery. However early diagnosis through stool examination may prevent life-threatening complications. This study investigated the presence of parasitic infections in surgically removed appendices as an etiology of acute appendicitis. A retrospective study included patients who had undergone surgery for acute appendicitis over a period of three years from Jan 2012 to Dec 2014. Demographic data, laboratory investigations, operative data and pathological findings, presence and type of parasites were retrieved. The results showed that out of 1536 patients with appendectomy done, 938 (61.1%) were males and 598 (38.9%) were females. Parasitic infection was demonstrated only in 0.4% (6 patients). Mean average age of these patients was 12 years. Enterobius vennicularis was present in 4 patients (66% of the parasitic affection) and Schistosoma mansoni in 2 patients (34% of the parasitic affection). Other etiologies were acute suppurative appendicitis (94.1%), chronic appendicitis (3.1%), tumors (0.3%), tuberculosis (0.2%) and actinomycosis (0.1%). Appendix was found normal in 2% of patients underwent appendectomy.

Methicillin-resistant Staphylococcus aureus in the western region of Saudi Arabia: prevalence and antibiotic susceptibility pattern.

BACKGROUND AND OBJECTIVES: Methicillin-resistant Staphylococcus aureus (MRSA) emerged in 1960 and was a problem confined largely to the healthcare setting, or hospital-associated MRSA (HA-MRSA). In the 1990s, community-associated MRSA (CA-MRSA) infections appeared. In Saudi Arabia, the prevalence of MRSA has increased in the past ten years and severe community-acquired infection has been reported. Our objective was to investigate the prevalence of MRSA and their antibiotic susceptibilities in the western region of Saudi Arabia. DESIGN AND SETTING: A retrospective review of the medical records of 186 S aureus infected patients diagnosed from November 2009 through October 2010. METHODS: S aureus was Identified based on Gram stain, catalase and coagulase tests. Susceptibility testing was performed using antibiotic discs and the VITEK 2 system. RESULTS: MRSA was isolated in 39.5% of the specimens. The isolates were commonly associated with wound, skin, and soft tissue infections (87.3%). The prevalence of MRSA was highest among patients who were 56 years old or older (52.2%). CA-MRSA infections represented 31.5% of community S aureus infections, while HA-MRSA accounted 52.6% of hospital S aureus (P=.0029). All MRSA isolates in our study were susceptible to vancomycin, linozolid and teicoplanin. However, multi-resistance was observed in 29.1% of the isolates and was significantly higher among HA-MRSA (P=.03). CONCLUSIONS: The prevalence of MRSA was 39.5%, and infection was commonly associated with wound, skin, and soft tissue infections. MRSA was more prevalent in hospitals and among older patients. All MRSA susceptible to vancomycin, linozolid and teicoplanin.

Frequency and antimicrobial susceptibility of gram-negative bacteria isolated from 2 hospitals in Makkah, Saudi Arabia.

OBJECTIVE: To estimate the prevalence and antibiotic susceptibility of the gram-negative bacteria isolated from 2 hospitals in Makkah. METHODS: This study was undertaken in 2 main tertiary care hospitals namely; Al-Noor Specialist Hospital, and Hera Hospital in Makkah, Kingdom of Saudi Arabia from October 2005 to March 2006. A total of 1137 gram-negative bacteria were identified in non-duplicate clinical specimens obtained from 965 patients of various body sites infections. Demographic data, identity of microorganisms, and antimicrobial susceptibilities were obtained from medical and laboratory records. RESULTS: The most prevalent gram-negative bacteria were Escherichia coli (31.6%), and Pseudomonas aeruginosa (31.2%), followed by Acinetobacter baumannii (10.8%), Klebsiella pneumoniae (8.3%), Klebsiella sp. (6.2%), Haemophilus influenzae (3.7%), Proteus sp. (3.3%), and Enterobacter sp. (1.9%). Results demonstrated that gram-negative bacteria have a high rate of resistance to commonly used antibiotics. Furthermore, multi-drug resistance was also common in this study. CONCLUSION: Our data showed a high rate of resistance among gram-negative pathogens in comparison with other countries in the world. The implementation of monitoring programs is an important part of the prevention strategy against the development of antibiotic resistance in hospitals.