Iranian Journal of Microbiology

A review on fungal surgical site infections: epidemiology, risk factors, main fungal agents, and prevention

Kiana Shirani — 2025-07-29

Fungal surgical site infections (SSIs) may be less common than bacterial SSIs but are a significant clinical issue due to their challenging diagnosis, higher morbidity, and rising incidence, particularly in immunocompromised patients. The epidemiology, risk factors, prevalent fungal pathogens, and prevention of SSIs caused by fungi are discussed in this narrative review. Systematic literature search for the period 2000 to 2024 was conducted on top databases using relevant MeSH keywords. The most frequent solitary pathogens were Candida spp., followed by Aspergillus and Mucor spp., especially in transplant, cardiac, and GI infections. The greatest challenge is extended length of hospital stay, broad-spectrum antibiotics, immunosuppression, and invasive interventions with prosthetic device or shunts. While it creates added burden, fungal SSIs go unnoticed by clinical practice and are rarely included in SSI prevention strategies. The review declares the significance of enhanced clinical vigilance and tailored antifungal prophylaxis in high-risk exposure surgical procedures. The review, based on the integration of existing information, provides clinicians and infection control practitioners with a framework of fungal SSIs so that they can be better equipped to assess risk, detect infection sooner, and focus prevention
efforts.

Pattern and trend of bacterial resistance in neonatal sepsis in infants admitted to the neonatal intensive care unit, from 2016 to 2021

Amir Naddaf — 2025-07-29

Background and Objectives: Neonatal septicemia is a significant cause of morbidity and mortality in neonatal intensive care units (NICUs). Understanding the patterns of antibiotic resistance and pathogen prevalence is crucial for effective treatment.
Materials and Methods: This cross-sectional study was conducted from 2016 to 2022 in the NICU of Vali-Asr Hospital in Tehran. All neonates diagnosed with septicemia were included. Data were collected using the hospital's registry system.
Results: A total of 477 infants were hospitalized with sepsis, with 71.7% classified as early-onset sepsis (EOS) and 28.3% as late-onset sepsis (LOS). The most common pathogens were coagulase-negative Staphylococcus (22.1%), Klebsiella pneumoniae (14.9%), and Staphylococcus epidermidis (14.3%). The highest antibiotic resistance was observed for erythromycin (89.8%), clindamycin (80.6%), gentamicin (66.1%), and ciprofloxacin (63.5%), while vancomycin showed the lowest resistance (11.2%). Significant associations were found between antibiotic resistance with low birth weight and chest tube intervention. Trends in antibiotic resistance varied over the study period, with a notable decrease in resistance in 2021.
Conclusion: The study highlights the high prevalence of antibiotic resistance in neonatal sepsis, emphasizing the need for continuous monitoring and tailored antibiotic stewardship programs. The findings underscore the importance of individualized treatment approaches to improve outcomes for neonates with sepsis.

Detection of carbapenemase production in Enterobacterales by mCIM and eCIM: a tertiary care hospital study

Touseefa Shafi — 2025-07-29

Background and Objectives: Carbapenem-resistant Enterobacterales (CRE) pose a major healthcare challenge due to high resistance rates and limited treatment options. This study characterized carbapenemase production among CRE isolates using phenotypic methods—Modified Carbapenem Inactivation Method (mCIM) and EDTA-Carbapenem Inactivation Method (eCIM)—as genotypic methods have limitations like restricted gene targets and mutations.
Materials and Methods: This six-month study was conducted at Sher-i-Kashmir Institute of Medical Sciences (SKIMS). Samples including swabs, respiratory specimens, pus, body fluids, and blood were cultured on Blood Agar and MacConkey Agar (HiMedia, India). Enterobacterales were identified using conventional methods and screened for carbapenem resistance. CRE isolates underwent mCIM and eCIM testing per CLSI guidelines.
Results: Among 471 Enterobacterales isolates tested, 160 (33.9%) were carbapenem-resistant. Of these, 97 (60.6%) were mCIM positive, indicating carbapenemase production. eCIM further identified 83 (85.5%) as metallo-beta-lactamase (MBL) producers and 14 (14.4%) as serine carbapenemase producers. CRE prevalence was higher in ICU settings and among males. Isolates showed high cephalosporin resistance, with multi-drug resistance (MDR) common in both MBL and serine carbapenemase producers.
Conclusion: The prevalence of CRE was found to be 33.9%. The findings underscore the critical need for continuous surveillance and stringent infection control measures to manage the spread of CRE in healthcare settings.

Exploring the genetic diversity and the association of drug resistance and biofilm production in Acinetobacter baumannii strains isolated from burn wound infections

Sanaz Khashei — 2025-07-29

Background and Objectives: Acinetobacter baumannii is considered a troublesome cause of infection in burn units, where its capability to form biofilm and resist antibiotics significantly hampers therapeutic success. This study explored the correlations between antimicrobial resistance profiles, biofilm-producing capacity, and genetic diversity of A. baumannii strains from patients with burn wound infection in Isfahan, Iran.
Materials and Methods: Ninety-six isolates were analyzed for antibiotic resistance using the disk diffusion technique and for biofilm formation through the microtiter dish assay. The prevalence of ten biofilm-related genes was investigated using specific primers. Clonal relatedness among bacterial strains was defined by Enterobacterial Repetitive Intergenic Consensus-Polymerase Chain Reaction (ERIC-PCR).
Results: A vast majority of isolates (99%) exhibited resistance to meropenem, ciprofloxacin, ceftriaxone, cefotaxime, piperacillin-tazobactam, and imipenem, qualifying them as extensively drug-resistant (XDR). Twenty-five percent of the strains were strong biofilm formers, while 68% demonstrated moderate or weak biofilm formation. The most commonly identified biofilm-related genes included bfmR (100%), ompA (100%), and bap (99%). A significant association was found between the production of biofilm, resistance to aminoglycosides, and the presence of csuE and bap genes. ERIC-PCR typing showed the presence of 3 clonal types and 7 single types, with biofilm producers predominantly clustering to clonal type 2.
Conclusion: This work highlights a notable prevalence of biofilm-producing XDR A. baumannii in burn patients, underscoring the need for continuous surveillance and enhanced infection control strategies.

Investigation of virulence factors and genes associated with biofilm and protease in Stenotrophomonas maltophilia isolates in Bushehr, Iran

Neda Shadvar — 2025-07-29

Background and Objectives: This study aimed to investigate the virulence factors and genes associated with biofilm and protease in Stenotrophomonas maltophilia in Bushehr, Iran.
Materials and Methods: Eighty-seven S. maltophilia isolates (67 clinical and 20 environmental isolates) were studied. The isolates were assessed for the production of virulence factors including several enzymes and biofilm. To detect rmlA, rpfF, spgM, smf-1, StmPr1 868 bp, StmPr1 1621 bp, and StmPr2 genes, PCR and sequencing were performed.
Results: All isolates (100%) produced DNase, hemolysin, protease, lipase, and hyaluronidase. Seventy-eight (89.7%) isolates were gelatinase producers, and 85 (97.7%) isolates were lecithinase producers. All isolates were biofilm producers: 79 (90.8%) isolates produced strong biofilm, 5 (5.7%) isolates produced moderate biofilm, and 3 (3.5%) isolates produced weak biofilm. The frequency of smf-1, rmlA, rpfF, and spgM was 93.1%, 86.2%, 26.4%, and 59.8%, respectively. The frequency of protease genes including StmPr1 868 bp, StmPr1 1621 bp, and StmPr2 was 12.6%, 41.4%, and 18.4%, respectively.
Conclusion: Our findings revealed a high frequency of isolates that produce DNase, hemolysin, protease, gelatinase, lipase, lecithinase, hyaluronidase, and biofilm. All isolates that harbored spgM or rpfF or both genes were strong biofilm producers. Notably, the presence of isolates that lacked spgM and rpfF genes but produced strong biofilm indicates that in addition to these two genes, other genes or factors may play a role in the production of strong biofilm. Based on this research, S. maltophilia in our area possesses the capability to produce several factors that could play roles in pathogenicity.

Exploring novel amides as efflux pump inhibitors for overcoming antibiotic resistance in multidrug-resistant Pseudomonas aeruginosa

Fahad Ullah — 2025-07-29

Background and Objectives: Pseudomonas aeruginosa (P. aeruginosa), a multidrug-resistant bacterium, represents a considerable risk in healthcare environments owing to its capacity to induce various infections. The resistance of P. aeruginosa is frequently linked to efflux pumps that actively remove antibiotics from the bacterial cell. This study investigates novel amide compounds as potential alternatives to address P. aeruginosa isolates exhibiting multidrug resistance mediated by efflux pumps.
Materials and Methods: Gram staining and biochemical assays revealed thirty-three multi-drug-resistant P. aeruginosa isolates from a tertiary care hospital Peshawar. After antibiotic susceptibility testing, efflux pumps were detected using Ethidium Bromide (EtBr) agar cartwheel technique and UV transilluminator. Novel amides were tested for efflux pump and anti-pseudomonal action against efflux pump-positive isolates utilizing agar well diffusion and micro broth dilution, including synergy with ciprofloxacin and gentamicin.
Results: Three high efflux pump activity P. aeruginosa isolates were chosen using ETBr agar cartwheel technique. Novel amides (ITC, ITD, ITE, DEP) block efflux pump, although TEM-cu is very antimicrobial. TEM-cu, DEP, ITC, and ITE have 0.19, 0.78, and 0.78 mg/ml MICs. Effectiveness against efflux pump-expressing P. aeruginosa is lowest with ITE (1.56 mg/ml). Together with ciprofloxacin and gentamicin, TEM-cu and DEP improved antimicrobial effectiveness.
Conclusion: TEM-cu is highly effective against efflux pump-positive P. aeruginosa, while amides like ITC, ITD, ITE, and DEP block these pumps. With significant reductions, DEP and TEM-cu improve ciprofloxacin and gentamicin efficacy. This method may help overcome P. aeruginosa efflux pump-mediated resistance.

The emerging threat of multidrug-resistant mecA gene-positive coagulase-negative Staphylococci

Samira Fattah Hamid — 2025-07-29

Background and Objectives: Coagulase-negative staphylococci (CoNS), previously classified as normal bacterial flora, have recently been associated with serious infectious diseases. The clinical isolation rate of these bacteria has increased in parallel with a rising prevalence of antibiotic resistance. Therefore, this study aims to determine the prevalence and species diversity of CoNS and their antibiotic susceptibility patterns.
Materials and Methods: Two hundred samples were collected from patients attending outpatient clinics. Bacterial genus, species, and antimicrobial susceptibility patterns were confirmed by the Vitek2 system. The mecA gene was then detected in all isolated bacteria using a polymerase chain reaction.
Results: The most frequently isolated bacterium was Staphylococcus haemolyticus accounting for 37.83% of the isolates and was identified in different specimens. The antibiotic susceptibility profile illustrated the highest resistance against cefoxitin, followed by erythromycin, tetracycline, gentamicin, levofloxacin, clindamycin, and tobramycin. The mecA gene was detected in 95.49%, and all isolates demonstrated resistance to one or more classes of antibiotics. The highest degree of multiple resistance involved six classes of antibiotics.
Conclusion: Methicillin resistance in coagulase-negative staphylococci is alarmingly high. Periodic surveillance of multidrug-resistant CoNS is essential to monitor changes in their antimicrobial susceptibility and to prevent their transition from opportunistic pathogens to regular pathogens.

Biofilm formation and eradication of Staphylococcus aureus: a study of culture conditions and endolysin ZAM-CS effect

Yasaman Ahmadbeigi — 2025-07-29

Background and Objectives: Staphylococcus aureus significantly contributes to healthcare-associated infections, with biofilm formation causing chronic, antibiotic-resistant cases. Because biofilms show high resistance to conventional antibiotics, endolysins have emerged as a promising alternative for treating antibiotic-resistant, biofilm-associated infections. This study evaluated the effects of four culture media and different incubation times on biofilm formation in methicillin-sensitive (MSSA) and methicillin-resistant (MRSA) S. aureus strains and assessed the anti-biofilm efficacy of a novel chimeric endolysin called ZAM-CS (catalytic domain of SAL-1 endolysin and binding domain of lysostaphin).
Materials and Methods: Biofilms were grown for 24, 48, and 72 hours in Mueller-Hinton broth (MHB), Luria broth (LB), terrific broth (TB), and tryptic soy broth (TSB). The crystal violet assay was used to assess the biomass of the biofilm. The optimal biofilm conditions were then used to test ZAM-CS’s activity at different concentrations.
Results: MSSA formed the strongest biofilms in TB. MRSA formed stable, high-biomass biofilms in TSB, TB, and LB, while MHB was the least supportive medium for both strains. ZAM-CS significantly reduced biofilm biomass in both MSSA and MRSA (up to 77%).
Conclusion: ZAM-CS’s rapid and potent anti-biofilm activity at low concentrations highlights its potential as a promising treatment against antibiotic-resistant S. aureus biofilm infections.

Eradication of Helicobacter pylori: challenges and advances

Yousra Sbibih — 2025-07-29

Background and Objectives: Helicobacter pylori, identified in 1982, remains a major cause of gastric infections. Despite extensive research, an ideal treatment regimen for its eradication is yet to be determined, with antibiotic resistance posing a significant challenge. This study, conducted at Mohammed VI University Hospital, aimed to evaluate and compare the effectiveness of different therapeutic protocols for H. pylori eradication.
Materials and Methods: This 13-month retrospective descriptive study was conducted at the Microbiology Laboratory of Mohammed VI University Hospital in Oujda, Morocco, to evaluate patients suspected of H. pylori infection using the urea breath test.
Results: A total of 190 patients were included, with an overall eradication rate of 73%. Three therapeutic protocols were tested, and bismuth concomitant therapy showed the highest eradication rate at 82%, outperforming the other regimens.
Conclusion: These findings highlight the importance of combining antimicrobial agents with antisecretory treatments to enhance eradication outcomes. The study also emphasizes the need for novel treatment strategies, particularly in light of rising antibiotic resistance. Vonoprazan-based regimens appear to offer a promising alternative, especially in the absence of antibiotic sensitivity testing. Future research should focus on optimizing treatment protocols while preserving beneficial gut flora.

A comparative study on diagnostic accuracy of rapid card test, IgM ELISA and real time-PCR in detecting scrub typhus infection: a cross-sectional study from tertiary care hospital

Gopinath Ramalingam — 2025-07-29

Background and Objectives: Scrub typhus, caused by Orientia tsutsugamushi, is a significant zoonotic illness in the Asia-Pacific region. Timely diagnosis is crucial, but overlapping symptoms and limitations of traditional diagnostic methods pose challenges. This study evaluates the diagnostic accuracy and utility of IgM ELISA, RT-PCR, and Rapid Card test for Scrub typhus, focusing on sensitivity, specificity, and practical applicability in endemic regions.
Materials and Methods: This cross-sectional study was conducted on 192 patients with suspected Scrub typhus at a tertiary care hospital from June to November 2024. Diagnostic tests included Rapid Card, IgM ELISA, and RT-PCR. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated, along with clinical and demographic data.
Results: IgM ELISA had the highest sensitivity (96.30%) and specificity (100%), followed by Rapid Card (sensitivity: 93.55%, specificity: 99.38%) and RT-PCR (sensitivity: 92.86%, specificity: 99.44%). Common symptoms included fever (99.4%) and headache (95.8%). Positive cases were mostly males (56.7%-64.3%) and individuals aged 21-40 years.
Conclusion: IgM ELISA shows high sensitivity and specificity for Scrub typhus, while RT-PCR aids early detection. The Rapid Card offers a quick field alternative. Combining molecular and serological methods can enhance diagnostic accuracy.

Implementation of hazard analysis and critical control points (HACCP) for microbial safety of enteral feeding solutions at Imam Khomeini Hospital, Urmia, Iran

Mohammad Yousefi — 2025-07-29

Background and Objectives: Enteral feeding solutions (gavage) play a vital role in supporting ICU patients who cannot eat by mouth. However, their preparation is vulnerable to microbial contamination, posing serious health risks. This study aimed to assess and improve the microbial safety of enteral feeding solutions prepared at Imam Khomeini Hospital in Urmia, Iran.
Materials and Methods: A three-phase intervention was conducted involving microbial and PCR analyses, source identification, and corrective measures. Initial testing revealed high contamination levels: coliform bacteria (>5×10³ CFU/mL), fungi (>3×10³ CFU/mL), and total mesophilic bacteria (>10⁴ CFU/mL). PCR analysis confirmed the absence of Escherichia coli and Klebsiella spp. Corrective actions—such as installing UV lighting, implementing enhanced cleaning protocols, and replacing the mixing device—were introduced.
Results: Post-intervention analyses showed complete elimination of detectable microbial contamination in the gavage solutions.
Conclusion: This study demonstrates that implementing a HACCP-based approach can effectively eliminate microbial contamination in enteral feeding solutions. The findings support the development of national guidelines and highlight the importance of standardized safety practices to improve patient care in hospital settings.

Antimicrobial and prebiotic properties of Weissella confuse B4-2 exopolysaccharide and its effects on matrix metalloproteinase genes expression

Maryam Firoozi — 2025-07-30

Background and Objectives: Bacterial polysaccharides have diverse applications, including antimicrobial compounds, bio-preservatives, prebiotics, and wound-healing hydrogels. Weissella confusa is notable for its high polysaccharide yield among lactic acid bacteria.
Materials and Methods: The bacteria were identified via 16s rRNA and exopolysaccharide (EPS) production was performed in a 10% skim milk and 10% sucrose medium. FT-IR, SEM, and HPTLC analyzed functional groups, spatial structure, and EPS units. Moreover, MTT assay, DPPH, and Kirby-Bayer disk method assessed cell proliferation, antioxidant activity, and antimicrobial effects of EPS. Additionally, Prebiotic potential and growth kinetics of exopolysaccharide were examined using the Thitiratsakul method. Furthermore, EPS effects on MMP and TIMP gene expression in fibroblast cells were evaluated.
Results: The purified polysaccharide from W. confusa B4-2 (Accession: KY290603), with a yield of 53 g/L, consists of glucose, fructose, and diglucuronic acid. This non-toxic polysaccharide (99-100% cell survival) exhibits 75% free radical scavenging activity along with significant antimicrobial effects against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. It also shows a high prebiotic score (0.912), accelerating wound healing in fibroblast cells while reducing collagen-degrading gene expression, particularly matrix metalloproteinases (MMPs). Notably, exopolysaccharides downregulated MMP1, MMP2, MMP3, and MMP9 gene expression levels by approximately 1.3, 1.2, 1.5, and 1.16 times, respectively.
Conclusion: These features highlight the commercial significance of W. confusa in the food, pharmaceutical, and health industries, surpassing lactobacilli with lower production yields.

Cytomegalovirus infection in patients attending a tertiary care hospital – single center experience

Bashir Ahmad Fomda — 2025-07-30

Background and Objectives: Human cytomegalovirus infection poses an important public health issue. This issue in India has not received enough attention. The majority of research workers have highlighted the seroprevalence of human cytomegalovirus. Hence this study was conducted to find out true magnitude of human cytomegalovirus disease.
Materials and Methods: Samples from 181 patients with suspected human cytomegalovirus disease were analyzed for human cytomegalovirus. DNA extraction was followed by real-time PCR. Human cytomegalovirus DNA-specific probes, fluorophore FAM™ and fluorophore JOE™ were utilized to detect human cytomegalovirus specific DNA and internal control at the same time. After completion of the assay, fluorescent growth curves were examined, and the response growth curves passing the threshold line in less than 36 cycles were deemed to be positive. All relevant clinical, demographic, and epidemiological information of the patients was also recorded.
Results: The most common clinical presentation was meningitis/meningoencephalitis. Out of the total samples, human cytomegalovirus infection was detected in 21% of the samples. Most positive samples were from infants (18.2%), followed by post-renal transplant cases (2.7%). Human cytomegalovirus was detected in urine samples (17.1%) followed by serum (3.8%). Four out of the 14 CSF samples were tested for other viruses as well, and they were positive for EBV (n=1, 7%), enterovirus (n=2, 14%), and varicella zoster virus (n=1, 7%).
Conclusion: PCR has a significant role in the detection of human cytomegalovirus disease at an early stage to avoid irreversible sequelae of late diagnosis.

Transplant failure in relation to BK viremia status among kidney transplant recipients in Jordan

Rabaa Y. Athamneh — 2025-07-30

Background and Objectives: BK polyomavirus (BKPyV) poses a significant threat to kidney transplant (KT) recipients due to immunosuppression, leading to BK-associated nephropathy (BKVN) and reduced transplant survival. This study aimed to determine the prevalence of BKPyV among kidney transplant recipients in Jordan and to evaluate the association between BKPyV activity and kidney transplant outcomes.
Materials and Methods: A retrospective observational study was conducted at the Jordanian Royal Medical Services Hospital (JRMS) from 2021 to 2024. Blood samples (n=157) from kidney transplant recipients were collected, and quantitative real-time PCR was performed to detect BKPyV DNA.
Results: The prevalence of BKPyV infection among kidney transplant recipients was 40.8% (n=64). Transplant failure occurred in 36% of cases (n=57), with BKPyV-DNA viremia observed in 74% of those with transplant failure (n=42). The prevalence of infection was significantly higher in patients under 18 years of age (81%, p<0.001) and in males (72%, p<0.001). BKPyV infection increased the odds of transplant failure tenfold.
Conclusion: In Jordan, the prevalence of BKPyV among kidney transplant recipients is high, particularly in males and younger patients. BKPyV significantly increases the risk of kidney transplant failure. Other studies are needed to further elucidate the impact of BKPyV on kidney transplant rejection and complications.

Immunogenicity assessment of Hepatitis A-VP1 and Hepatitis B surface antigen (HBsAg) fusion protein: a novel bivalent vaccine candidate

Mina Hannan — 2025-07-30

Background and Objectives: Subunit vaccines have the privilege of utilizing immunogenic parts of the variable viruses. The current preventive vaccines against Hepatitis A are based on live-attenuated virus or wild-type growth in cell culture, which is a time-consuming and costly procedure. Thus, the investigation of immunogenic Hepatitis A Virus (HAV) regions seems to be a rational priority. We aimed to evaluate a novel chimeric protein composed of truncated HAV-VP1 and Hepatitis B surface antigen (HBsAg) as a bivalent vaccine candidate in BALB/c mice.
Materials and Methods: The HAV-VP1 (amino acids 99 to 259) and HBsAg fusion protein were applied as a bivalent vaccine in combination with adjuvants. The purified protein was administered through different regimens via subcutaneous injection. Two weeks following the final immunization, serum samples were gathered to assess the humoral responses. Moreover, splenocytes were investigated and assessed for IL-5 and IFN-γ secretion.
Results: The immunized mice with recombinant truncated HAV-VP1-AAY-HBsAg showed a significant immune response, especially in combination with the M720 adjuvant. Humoral immune response results indicated Th1 switching by IgG2a and IgG2b dominancy. Moreover, IFN-γ secretion reached the highest rate in the truncated HAV-VP1-AAY-HBsAg+M720 recipients (p<0.0001).
Conclusion: The HAV-VP1-AAY-HBsAg protein subunit vaccine could help the immune system fight HAV and HBV by stimulating both the humoral and cellular immune systems. The formula proposed in this study has the potential to produce an endemic vaccine based on the circulating HAV viruses in Iran.

The prevalence of pediatric nosocomial fungal infections

Parisa Badiee — 2025-07-30

Background and Objectives: The aim of this study was to identify the incidence of nosocomial fungal infections in pediatric patients and evaluate the etiological agents, risk factors, and sites of infections.
Materials and Methods: Clinical samples were cultured to assess fungal colonization. When fungal nosocomial infections were suspected according to the European Organization for Research and Treatment of Cancer criteria, clinical samples were evaluated using direct microscopic, culture, and molecular methods. Susceptibility patterns of the isolates were evaluated according to the Clinical and Laboratory Standard Institute.
Results: From the 1450 patients, 190 cases (5.5%) were evaluated for nosocomial fungal infections. Candida colonization was observed in 35 (18.4%) patients. The rate of nosocomial fungal infections in pediatrics was 2.69% (12 cases with proven and 27 cases with probable infections, 39/1450). Bloodstream and lungs were the frequent infected sites of patients’ body. Aspergillus species (Aspergillus flavus and Aspergillus fumigatus), Candida species (Candida albicans, Candida parapsilosis, Candida glabrata) and Mucorales were the etiologic agents of infections. Caspofungin and luliconazole were effective antifungal agents for isolated fungi. The rate of mortality in infected patients suffering from proven and probable infections was 15.4% (6/39 cases).
Conclusion: Due to the high mortality rates of fungal infections in pediatrics, it is essential to identify modifiable risk factors, and implement control measures along with early detection techniques in pediatric populations.

The efficacy of luliconazole and caspofungin on planktonic and biofilm of Candida albicans from different sources

Mahboubeh Shabanzadeh — 2025-07-30

Background and Objectives: The ability of Candida albicans to produce biofilm is considered an important pathogenic factor. In addition, the low sensitivity of biofilms to antifungal drugs is a challenge for patients, clinicians, and laboratory workers. We aimed to investigate the effectiveness of luliconazole and caspofungin on the planktonic and biofilm types of C. albicans strains.
Materials and Methods: Fifty C. albicans from vaginitis, candiduria, gastrointestinal candidiasis, and saliva were examined for antifungal susceptibility against caspofungin and luliconazole using the CLSI M27 guideline. Moreover, the susceptibility of biofilms was detected using 96 well microplates and the MTT method.
Results: The capacity of the isolates to produce biofilm within 2, 6, and 24 h was different, however, all tested isolates produced biofilm after 24 h. Vaginal and esophagitis isolates had a high and low ability for biofilm production during 24-hour incubation. In our study, 90% of isolates were sensitive to caspofungin, while 7.5 and 2.5% of them were intermediate and resistant. The MIC range of all isolates against luliconazole was 0.01562-1 µg/mL.
Conclusion: The MICs of biofilms were 15.6, and 171.3 higher than that of planktonic cells for caspofungin and luliconazole, respectively. Moreover, paradoxical and trailing effects occurred at 4 and 32 µg/mL of caspofungin and luliconazole, respectively.

Molecular identification and phylogenetic analysis of yeast strains isolated from dairy products in Isfahan, Iran

Rasoul Mohammadi — 2025-07-30

Background and Objectives: Yeasts play a dual role in dairy processing, serving as beneficial fermentative agents that enhance product quality through flavor, texture, and probiotic properties, while also posing spoilage risks if uncontrolled. This study aimed to characterize yeast isolates from industrial and traditional dairy products in Isfahan using PCR-sequencing and phylogenetic analysis.
Materials and Methods: A total of 155 dairy samples (fresh/stored, traditional/industrial) were collected. Yeasts were cultured and identified via PCR amplification and sequencing of the ITS1-5.8S rDNA-ITS2 region.
Results: Analysis of ITS sequence data identified 28 yeast strains representing eleven species across seven genera, including Saccharomyces cerevisiae (n=8) Kluyveromyces marxianus (n=6), Pichia kudriavzevii (n=4), Candida orthopsilosis (n=2), Pichia membranifaciens (n=2), Pichia cactophila (n=1), Pichia fermentans (n=1), Galactomyces candidum (n=1), Torulaspora delbrueckii (n=1), Debaryomyces hansenii (n=1), and Kluyveromyces lactis (n=1). Phylogenetic analysis grouped isolates into two clusters. Industrial cheese and both industrial/traditional yogurts showed the highest yeast diversity and counts. Notably, C. orthopsilosis was found only in industrial milk and cheese, suggesting potential processing-related contamination.
Conclusion: This study highlights the diversity of yeast microbiota in dairy products and underscores the efficacy of ITS sequencing for accurate yeast identification in the dairy industry, aiding quality control and spoilage prevention.