BACKGROUND AND OBJECTIVES

Staphylococcus aureus poses a significant public health threat globally, where both community and hospital-acquired infections are prevalent. The escalating antimicrobial resistance highlights the urgent need for alternative therapies. Hence, traditional medicine using plant extracts offers a potential avenue for novel antibacterial agents. This systematic review aimed to evaluate the existing literature on the antibacterial properties of Philippine plants against S. aureus to provide focus on drug development of a plant-derived antibacterial for this pathogen.

METHODS

Following PRISMA guidelines, a comprehensive search was conducted in PubMed/Medline, SCOPUS, and Herdin databases. Inclusion criteria encompassed in-vitro studies evaluating the antibacterial activity of crude plant extracts sourced from Philippines plants against S. aureus. Data extraction and quality assessment were performed independently by two reviewers, with discrepancies resolved by the third and fourth reviewers.

RESULTS

Of the 413 initial studies identified, nine (9) met the eligibility criteria. The highest zone of inhibition was demonstrated by Lippia micromera L. leaf essential oil at 26.3±1.5 mm, while moderate antibacterial activity was shown by essential oils from Alpinia elegans, Piper quinqueangulatum, and Alpinia cumingii at MIC values of 512 µg/mL, 512 µg/mL, and 1,024 µg/mL, respectively. Other Philippine plants showed a wide range of activity, with MIC values between 50 ?g/mL and 25 mg/mL, MBC values from 78 to 5000 ?g/mL, and ZOI ranging from 5 to 38 mm. However, the overall quality of evidence in these other studies are compromised by bias and incomplete reporting.

CONCLUSION

Leaf essential oils from Alpinia elegans, Piper quinqueangulatum, and Alpinia cumingii demonstrated moderate antibacterial activity against S. aureus. Additionally, the essential oils of Lippia micromera L., Plectranthus amboinicus Lour. Spreng, and Cymbopogon citratus exhibited antibacterial activity against both S. aureus and Methicillin-resistant S. aureus (MRSA) in disk diffusion assays. Majority of the studies gathered had high risk of bias according to the quality assessment criteria tool used in the study. Thus, this systematic review also emphasizes the need for improved methodological rigor on reported in-vitro antibacterial studies.

Staphylococcus ; Staphylococcus Aureus ; Systematic Review

A singular medical incident can alert health officials to an emerging, if not widespread, but possibly undetected publichealth concern.

Our issue contains a remarkable case of a ruptured hepatic abscess in a 3-year-old, which turned out to be MethicillinresistantStaphylococcus aureus (MRSA) by authors Torrico and Tarnate.The concern is that the infection is communityacquired,and the patient was immunocompetent. This sounds the alarm for the occurrence of antimicrobial resistance (AMR)in the communities and calls for a response from health authorities to investigate, analyze, and propose solutions for sucha sentinel event.

We need to support these efforts and, in this issue, we publish such work from our investigators. Antimicrobial resistanceis an urgent global health concern.The impact is magnified in low to middle-income countries where health risks are high,and health infrastructure is weak. Thus, it is imperative that determinants of AMR are scrutinized to allow crafting offocused strategies to combat the problem.

The article by Dela Cruz and Hernandez on the prevalence and practices of antibiotic misuse among adult residents ofRodriguez, Rizal, contributes to this analysis.The paper reveals a disturbing prevalence of self-medication and identifiesbarriers to accessing proper health education and care. This is a global problem, and the paper from Brazil relates the observationof community pharmacists of antibiotic misuse to the rise of antimicrobial resistance.

Dela Cruz and Hernandez recommend stricter antibiotic regulation, and this falls squarely into the scope of concernof another article in this issue, the “Research Needs in Philippine Pharmaceutical Sciences: A Qualitative Perspective fromRegulatory and Clinical Research Sectors of the Pharmaceutical Industry” by Pena and co-authors.Interestingly, whiledrug registration and clinical trials were the focus of the paper, it may be a desired expansion of the regulatory reach of theindustry to temper the use of antibiotics as it is being dispensed to end users.Antimicrobial stewardship involves ethicalpromotion of use and equitable access to appropriate treatment, and these concerns require the responsible participation of thepharmaceutical industry.

Health challenges are complex. The analysis of these challenges requires surveillance of literature for sentinel events, useof community-based research to investigate phenomena, and system mapping to identify relevant sectors to improve strategyand to involve relevant stakeholders.

We support this type of scholarship, which seeks to expand the focus from isolated clinical interventions towards placinga spotlight on relevant work that will lead to impactful reform of broad health ecosystems.

Human ; Child Preschool: 2-5 Yrs Old ; Therapeutics ; Staphylococcus Aureus ; Pharmaceutical Preparations ; Research Personnel ; Health Services Needs And Demand ; Methicillin-resistant Staphylococcus Aureus ; Antimicrobial Stewardship

Methicillin-resistantStaphylococcus aureus(MRSA) is an uncommon etiologic agent of hepatic abscess in children, particularly those without an underlying immunocompromised condition.

We describe a rare case of community-acquired MRSA (CA-MRSA) hepatic abscess with rupture into the anterior abdominal wall in an otherwise healthy 3-year-old Filipino male, manifesting as a one-week history of an enlarging epigastric mass accompanied by abdominal pain and fever. He was treated noninvasively with ciprofloxacin (intravenous at 10 mg/kg every 12 hours for 14 days followed by oral at 15 mg/kg every 12 hours for 28 days), and clindamycin (intravenous at 10 mg/kg every 6 hours for 14 days followed by oral at 10 mg/kg every 6 hours for 28 days), resulting in the resolution of the hepatic abscess and its associated symptoms.

CA-MRSA hepatic abscess is extremely rare in immunocompetent children, and an appropriate diagnostic approach involving imaging and culture studies is crucial in its diagnosis and management.

Human ; Child Preschool: 2-5 Yrs Old ; Therapeutics ; Staphylococcus Aureus ; Staphylococcus ; Residence Characteristics ; Research Report ; Dihydrotachysterol

Purulent pericarditis is a rare occurrence in the era of modern antibiotics. It is most often caused by organisms such as Staphylococcus aureus, Streptococcus pneumoniae, Viridans streptococci, Haemophilus influenzae and anaerobic bacteria with Streptococcus pyogenes (S.pyogenes) being a possible, though very uncommon etiology. This case represents an occurrence of S. pyogenes pericarditis in an apparently healthy female with no known immunocompromising condition. A 37-year-old female, married, real estate agent with no comorbidities came in for chest pain radiating to the upper back, relieved with leaning forward. Cardiac biomarker was normal, ECG demonstrated diffuse ST-segment elevation and PR segment depression, while imaging showed lobar pneumonia. Blood tests showed leukocytosis with neutrophilic predominance and workup for immunocompromised state was negative. The 2D echo showed large pericardial effusion with tamponade physiology. An urgent pericardiocentesis was done. Cultures grew Streptococcus pyogenes confirming the diagnosis of acute purulent pericarditis. Daily drainage of pericardial effusion, colchicine, ibuprofen was initiated together with antibiotics and the patient had resolution of pericardial effusion. Acute pyogenic pericarditis with cardiac tamponade is a rare but serious condition that requires prompt recognition and intervention. Early diagnosis, through a combination of clinical suspicion, ECG and echocardiography is crucial for initiating timely treatment.

Human ; Female ; Adult: 25-44 Yrs Old ; Viridans Streptococci ; Streptococcus Pyogenes ; Streptococcus Pneumoniae ; Staphylococcus Aureus ; Streptococcal Infections ; Electrocardiography ; Echocardiography ; Early Diagnosis

INTRODUCTION

Burn wound infection is a significant risk factor in the morbidity and mortality of burn wound patients. Previous studies in our institution showed bacterial colonization in burn patients seen beyond 24 hours post-injury. The microbiological profile of burn wounds seen within 24 hours, including the presence and risk factors for wound colonization, has not been determined in our Burn Center.

OBJECTIVES

To identify the presence and risk factors for burn wound colonization in burn patients seen less than 24 hours after injury and determine the microbiological profile and antibiotic susceptibility patterns in colonized burn wounds.

METHODS

One hundred eighty-nine burn patients who were seen at and admitted to the UP Philippine General Hospital ATR Burn Center within 24 hours of the burn injury from June 2021 until July 2023 were included in the study. Demographic and clinical data were collected upon admission. A total of 635 swab samples were collected from 189 patients and were sent for identification of aerobic organisms by standard culture methods and antibiotic sensitivity tests using the Kirby-Bauer disc diffusion method. Association of patient characteristics (area of injury, time received post-injury, previous hospital care, place of injury, percent burn injury, etiology, mode of transport, and type of dressing prior to admission) were determined using Chi square test of independence.

RESULTS

Out of 189 burn patients seen within 24 hours after injury included in the study, 58.73% (n = 111) of patients, and 49.29% (n = 313) of swabs showed bacterial colonization. Burn wound colonization was associated with area of injury/body region (χ2 5 = 16.29, p = .0061), time received post-injury (χ2 3 = 24.62, p < 0.0001, post hoc Fisher’s test for 6-12 hours vs. within the first 6 hours: p < 0.0001), place of burn injury (χ2 2 = 18.17, p = 0.0001, post hoc Fisher’s test work vs. home: p = 0.0006, work vs. outdoors: p = 0.0015), percent burn injury (χ2 4 = 21.40, p = 0.0003, post hoc Fisher’s test 25-49% vs. 0-9%: p = 0.004, 50-75% vs. 0-9%: p = 0.002), and etiology of burn injury (χ2 2 = 37.05, p < 0.0001, post hoc Fisher’s test scald vs. flame: p = 0.0012, electrical vs. flame: p < .0001). From 313 positive samples, 357 isolates were identified. Staphylococcus (58.8%) was the most common organism isolated. It was noted that out of the total isolates, 15 (4.2%) were identified to be methicillin-resistant S. aureus (MRSA) while 5 isolates (1.4%) were methicillin-resistant S. epidermidis (MRSE). Streptococcus (10.4%) and Acinetobacter (6.2%) were the second and third most common organisms, respectively. Other groups identified were Aeromonas, Bacillus, Enterobacter, Pseudomonas, Klebsiella, and diphtheroids. Frequency of bacterial isolates differed across body regions, time received post-injury, percent burn injury, and etiology of burn injury. Resistance to one antibiotic was observed in 36.84%, 6.25%, and 63.64% of Staphylococcus, Streptococcus, and Acinetobacter isolates tested, respectively. Resistance to more than 1 antibiotic was observed in 48.68% of Staphylococcus isolates and 50.0% of Streptococcus isolates tested. Among the 51 S. aureus isolates, 29.1% were methicillin-resistant S. aureus (MRSA).

CONCLUSION

In burn patients seen within 24 hours after injury, about half of burn wounds and more than half of patients showed the presence of microbial growth. Potential risk factors for positive microbial growth in a burn wound during this timeframe were area of injury/ body region, place of injury, time received post-injury, percent TBSA burn, and etiology of burn injury. The most common isolate was Staphylococcus spp. More than half of Staphylococcus isolates showed antibiotic resistance, with a significant number showing multidrug resistance. More than a quarter of S. aureus isolates were methicillin-resistant S. aureus (MRSA). These results suggest that bacterial isolates can colonize burn wounds even within 24 hours post-injury and may exhibit antibiotic resistance.

Human ; Burns ; Wounds And Injuries ; Wound Infection ; Methicillin ; Klebsiella ; Methicillin-resistant Staphylococcus Aureus ; Drug Resistance, Multiple

Empyema Necessitans is a rare complication of Empyema Thoracis that is caused by a longstanding pleural infection such as persistent pleural effusion. It is caused by an extension of pus to nearby structures including the chest wall and is usually caused by Mycobacterium tuberculosis infection. It is difficult to diagnose since its features are similar to those of other disease entities such as malignancies; therefore, imaging tests such as a chest CT scan are helpful in establishing the diagnosis. In addition, other diagnostic tests such as acid-fast stain and GeneXpert may be falsely negative due to inadequate or incorrect sampling location. One such case is this 30-year-old female with chronic cough and recurrent pleural effusion that progressed to Empyema Necessitans presenting as an abdominal mass where sputum GeneXpert was negative, but aspirate of the abdominal mass showedMycobacterium tuberculosis. Prompt initiation of anti-tuberculosis treatment once diagnosis is confirmed as well as emphasizing its completion is imperative for definitive treatment. As such, family physicians have a vital role in navigating patients for further workup and necessary referrals for a multidisciplinary management especially in persistent disease processes as well as screening and treatment of the family for holistic care.

Human ; Female ; Adult: 25-44 Yrs Old ; Mycobacterium Tuberculosis

OBJECTIVES: To detect prfA and hly toxin genes of Listeria monocytogenes using polymerase chain reaction (PCR) and colloidal gold technology. METHODS: L. monocytogenes DNA was extracted by boiling method. With prfA and hly of L. monocytogenes as the target genes, the 5' ends of upstream and downstream primers of prfA gene were labeled with 6-FAM and biotin, and the 5' ends of upstream and downstream primers of hly gene were labeled with digoxin and biotin, respectively, to establish the toxin gene detection method. Using cloning transformation, sequencing analysis, cloning of positive control products, the detection kid was developed and its specificity, sensitivity, reproducibility and stability were tested, followed by verification with sample testing. RESULTS: The concentration of L. monocytogenes DNA extracted by boiling method was 148.81±0.97 ng/μL, and the A₂₆₀/A₂₈₀ ratio ranged from 1.8 to 2.0. The PCR products showed a 100% homology with the gene sequences in GenBank database after cloning, transformation and sequencing. The colloidal gold strip yielded positive results only for L. monocytogenes samples without cross-reactions with Staphylococcus aureus, Escherichia coli or Bacillus cereus, and its minimum detection limit was 10^-2 ng/μL, demonstrating a 10-fold greater sensitivity of the test than agarose gel electrophoresis. The test also showed good reproducibility of the results when performed by different operators with good stability of the test strips after storage for 6 to 12 months. The test results showed that this kit could accurately and quickly detect L.monocytogenes in the test samples. CONCLUSIONS The detection kit developed in this study can simultaneously detect prfA and hly toxin genes of L. monocytogenes with good specificity, sensitivity, reproducibility and stability for use in food safety inspection.
Listeria monocytogenes/isolation & purification* ; Gold Colloid ; Bacterial Toxins/genetics* ; Polymerase Chain Reaction/methods* ; Hemolysin Proteins/genetics* ; Bacterial Proteins/genetics* ; DNA, Bacterial/genetics* ; Food Microbiology ; Heat-Shock Proteins

OBJECTIVES: To evaluate the photothermal and antibacterial activities of polydopamine-modified phycocyanin nanoparticles (PDA@PC NPs) and their capacity for promoting wound healing. METHODS: PDA@PC NPs were synthesized from phycocyanin (C-PC) and dopamine hydrochloride using a one-pot method. The photothermal activity of the nanoparticles was assessed in vitro by 808 nm laser irradiation, their biocompatibility was evaluated using CCK-8 assay, and their photothermal antibacterial activity by plate colony counting. In adult male BALB/c mice, two symmetrical full-thickness skin wounds (1.0 cm ×1.0 cm) were created on both sides of the spine, and 200 μL of Staphylococcus aureus suspension was inoculated into the wounds. The mice were divided into control group, PDA@PC NPs group, and PDA@PC NPs with laser irradiation group, and wound healing rates and histomorphological changes in the wound tissues were evaluated on days 0, 7 and 14 after modeling. RESULTS: The synthesized PDA@PC NPs exhibited no obvious cytotoxicity up to a concentration of 500 μg/mL and showed strong photothermal and antibacterial activities in response to 808 nm laser irradiation. In the mouse models, the size of the infected skin wounds showed substantial reduction at 7 and 14 days in PDA@PC NPs group and PDA@PC NPs with laser irradiation group, and the mean wound healing rate was faster in the latter group. HE staining and Masson's trichrome staining revealed extensive granulation tissue formation and collagen deposition on the wound surfaces in both of the treatment groups, and these changes were more obvious in the PDA@PC NPs with laser irradiation group. CONCLUSIONS PDA@PC NPs possess excellent photothermal and antibacterial activities and can effectively promote wound healing in mice.
Animals ; Indoles/chemistry* ; Wound Healing/drug effects* ; Mice ; Mice, Inbred BALB C ; Male ; Nanoparticles ; Polymers/chemistry* ; Phycocyanin/chemistry* ; Skin/injuries* ; Staphylococcus aureus/drug effects* ; Anti-Bacterial Agents/pharmacology*

OBJECTIVES: To investigate the efficacy of Lactobacillus plantarum ZG03 (L. plantarum ZG03) for ameliorating oxidative stress in zebrafish. METHODS: We evaluated the growth pattern of L. plantarum ZG03, observed its morphology using field emission scanning electron microscopy, and assessed its safety and potential efficacy with whole-genome sequencing for genetic analysis. FITC-labeled ZG03 was used to observe its intestinal colonization in zebrafish. In a zebrafish model of 2% glucose-induced oxidative stress, the effect of ZG03 was evaluated by assessing the changes in neutrophils in the caudal hematopoietic tissue (CHT), superoxide dismutase (SOD) activity, reactive oxygen species (ROS) levels, and malondialdehyde (MDA) content. Liquid chromatography-mass spectrometry-based targeted metabolomics was used for analyzing short-chain fatty acids (SCFAs) in the zebrafish, and the antioxidant effects of the key metabolites (acetate, propionate, and caproate) were tested. RESULTS: On MRS agar, L. plantarum ZG03 formed circular, smooth, moist, and milky-white colonies with a rod-shaped cell morphology. Genomic analysis revealed abundant sugar metabolism gene clusters. After inoculation of FITC-labeled L. plantarum ZG03 in zebrafish, green fluorescence was clearly observed in the intestinal bulb, mid-intestine, and hind intestine. In zebrafish with glucose-induced oxidative stress, L. plantarum ZG03 significantly reduced ROS levels and the number of neutrophils in the CHT with increased SOD activity. L.plantarum ZG03 significantly increased the content of SCFAs including acetic acid, propionic acid, and caproic acid in zebrafish metabolites. In addition, sodium acetate, sodium propionate, and sodium caproate in the SCFAs significantly increased SOD activity in the zebrafish models. CONCLUSIONS L. plantarum ZG03 ameliorates oxidative stress in a glucose-induced zebrafish model through its metabolites, particularly the SCFAs including acetic acid, propionic acid and caproic acid.
Animals ; Zebrafish/metabolism* ; Oxidative Stress ; Lactobacillus plantarum/metabolism* ; Fatty Acids, Volatile/metabolism* ; Probiotics ; Reactive Oxygen Species/metabolism* ; Superoxide Dismutase/metabolism*

Otitis media is an infection of the middle ear mainly caused by bacteria, and current treatments rely heavily on antibiotics. However, the emergence of antibiotic-resistant bacterial strains seriously affects their efficacy. In our study, we found that extracellular vesicles (EVs) derived from human natural killer cells (NKs) inhibit the proliferation of both standard and levofloxacin (LVX)-resistant strains of Staphylococcus aureus in a dose-dependent manner. Moreover, compared to LVX, EVs were more effective at reducing effusion and rescuing hearing thresholds in animal models. For LVX-sensitive strains, EVs were significantly more effective in terms of curative time but not curative rate. For LVX-resistant strains, EVs were significantly more effective in terms of both curative rate and curative time when applied alone or applied jointly with LVX. In summary, we found that NK EVs are highly effective in treating otitis media, providing an alternative approach for treating this common disease.
Killer Cells, Natural/metabolism* ; Exosomes/metabolism* ; Animals ; Humans ; Otitis Media/therapy* ; Staphylococcus aureus/drug effects* ; Disease Models, Animal ; Anti-Bacterial Agents/pharmacology* ; Levofloxacin/pharmacology*