Rapid Molecular Test Research Articles

Cartridge-Based Nucleic Acid Amplification Test Compared to Fine Needle Aspiration Cytology in Suspected Cases of Tubercular Lymphadenitis (the Indian Experience)

INTRODUCTION: Diagnosis of tubercular lymphadenitis is daunting as there are varied clinical presentations and no single confirmatory gold standard test. Cartridge-based nucleic acid amplification test (CBNAAT) of the lymph node is a rapid molecular diagnostic test for simultaneously detecting tuberculosis (TB) and rifampicin resistance. AIM: To evaluate the performance of the CBNAAT test for detecting M. tuberculosis in lymph node specimens compared to fine needle aspiration cytology (FNAC). MATERIALS AND METHODS: The study was conducted in a rural tertiary care hospital in central India. A total of 180 patients clinically suspected of tubercular lymphadenitis were included. The male-to-female ratio was 1:1.3. The average age was 33.3 years. The age group 21–40 years had the highest number of cases. The most common complaints among the patients were fever (29.4%), followed by loss of appetite (9.5%), weight loss (9.5%), and cough (6.6%). However, most patients presented to the hospital with only lymphadenopathy (44.4%). The most common site involved was the anterior cervical lymph node (78.8%), followed by the axillary group (10.5%), submandibular (2.8%), inguinal (2.8%), supraclavicular (2.2%), submental (1.7%) and infraclavicular (1.1%) group of lymph nodes. The patients were subjected to both FNAC and CBNAAT testing. Results were reported as positive or negative for M. tuberculosis as CBNAAT gives a semiquantitative estimate of the concentration of bacilli. Rifampicin resistance results were reported as detected or not detected. RESULTS: Cytological examination of the lymph node aspirates revealed that most were tubercular lymphadenitis cases. Cytomorphological analysis of the cases of tubercular lymphadenitis revealed Type 6 (tubercular abscess) as the predominant pattern. CBNAAT testing detected 26 cases of M. tuberculosis and three cases of rifampicin resistance. The study reported a specificity of 92.92% and low sensitivity of 26.86% of combined FNAC and CBNAAT is much higher compared to only CBNAAT. CONCLUSION: CBNAAT, along with FNAC, is a valuable addition in first-line investigations of tubercular lymphadenitis to make a timely diagnosis.

A-367 Development of a Multimodal Point-of-Care Diagnostic Platform to Perform Rapid, Accurate, and Cost-Effective Molecular, Immunochemistry, Clinical Chemistry, and Cytometry Tests

Abstract Background Access to point-of-care (POC) testing can make a significant impact on the quality of care. However, because POC diagnostic platforms available today are expensive and only perform one type of test, clinicians are unable to implement all the POC tests they wish to perform. Fluxergy is developing a multimodal POC diagnostic platform that consolidates diverse diagnostic modalities into a single, compact platform to minimize the cost of POC testing and standardize testing workflow for the most common clinical chemistry, hematology, immunochemistry and molecular tests. This study describes feasibility studies performed to benchmark these assay modalities on the Fluxergy Analyzer. Methods Fluxergy Analyzer: The Fluxergy Analyzer integrates conventional detection systems—colorimetric, fluorometric, and electrochemical—into a singular POC platform. This unique design expands -omics testing capabilities, including molecular, immunochemistry, clinical chemistry, and hematology within a single instrument. Benchmarking Feasibility Studies: Molecular benchmarking was performed using a multiplex respiratory panel on contrived samples in UTM/VTM. Immunochemistry benchmarking was performed using a procalcitonin assay on spiked sodium citrate plasma samples. Cytometry benchmarking was performed using a white blood cell count (WBC) assay and testing contrived samples whole blood samples. Results For molecular testing, the Fluxergy Analyzer was able to accurately detect flu A, flu B, SARS-CoV-2, and RSV with agreements with the Luminex ARIES® Flu A/B & RSV Assay and Cepheid Xpert® SARS-CoV-2 test results. For immunochemistry testing, the Fluxergy Analyzer accurate quantified PCT levels at 0.3, 0.6, 1.25 and 2.5 ng/mL. For hematology testing, the Fluxergy Analyzer demonstrated a strong correlation across the reportable range against the standard of care HemoCue analyzer. For clinical chemistry testing, the Fluxergy Analyzer demonstrated a strong correlation against the Siemen’s epoc® Blood Analysis System. Conclusions The Fluxergy Analyzer is uniquely suited to offer a comprehensive menu of the most common POC tests on a single, cost-effective platform.

Nosocomial cluster of patients infected with imipenemase-1-producing Enterobacter ludwigii.

Introduction. Imipenemase (IMI) enzymes are an uncommon class A carbapenemases that have been isolated from aquatic environments and, occasionally, from clinical isolates of Enterobacterales.Aim. We describe a cluster of three patients infected by IMI-1 carbapenemase-producing Enterobacter ludwigii (IMI-1-Elud) in a tertiary university hospital in Gran Canaria, Spain.Methodology. Antimicrobial susceptibility was determined using the Vitek2 AST-N355 card and antibiotic gradient strips. The modified carbapenem inactivation method (CIM) test was performed in cases where the ertapenem MIC value was higher than 0.125 mg l-1. The carbapenemase was identified by PCR and DNA microarray and later characterized by whole-genome next-generation sequencing (NGS) with Illumina.Results. Three patients presented thoracic or abdominal infections caused by IMI-1-Elud ST1677 from 14 June 2022 to 14 July 2022. All patients underwent at least one gastroscopy during their admission, and two of them were located in adjoining rooms. Isolates were resistant to carbapenems, colistin and fosfomycin but susceptible to ciprofloxacin. IMI/NMC-A carbapenemase was detected by PCR and hybridization test and confirmed by NGS as IMI-1. All patients underwent at least one gastroscopy, and two of them were in nearby rooms. Patients showed microbiological and clinical improvement following focus drainage and targeted antibiotic treatment with a fluoroquinolone.Conclusions. This study reports the first documented global outbreak of patients infected with IMI-1-Elud. The source appeared to be related to endoscopes. Contact transmission may also have played a role. A screening method such as the modified CIM test is crucial for detecting less common carbapenemases that might not be identified by rapid molecular or immunochromatographic tests, as these often do not include bla IMI genes, which could lead to the undetected dissemination of carbapenemase-producing Enterobacterales. Effective infection source control and targeted treatment are essential for achieving a favourable clinical outcome.

Evaluation of Multiplex loop-mediated isothermal amplification assay for the detection of Mycobacterium tuberculosis complex from clinically suspected cases of pulmonary tuberculosis

Tuberculosis (TB) is the second leading cause of death from a single infectious agent worldwide. Bangladesh ranks 7th among the 30 high TB burdened countries in the world. Accurate detection of Mycobacterium tuberculosis complex (MTBC) is challenging for developing countries as most of the resource poor settings are not suitable to perform molecular techniques.The purpose of the study was to compare the multiplex TB-LAMP assay with MTB/NTM qPCR, culture, Z-N staining, and fluorescence microscopy in order to assess the effectiveness of the LAMP assay for detecting cases of pulmonary tuberculosis.This research work was done from March 2022 to February 2023. Fulfilling the inclusion criteria 130 sputum samples were collected. TB-LAMP assay, qPCR, culture in L-J media, Z-N staining and fluorescence microscopy were performed.Out of 130 samples qPCR detected MTBC in 56.92% cases and TB-LAMP detected 53.85%. MTBC was detected by culture 46.15%, by Fluorescence microscopy 40.77% and Z-N staining 36.92%. TB-LAMP detected 16.93% more cases than Z-N staining and 13.08% more cases than fluorescence microscopy. The sensitivity, specificity, positive, and negative predictive values of multiplex-LAMP assay were 95%, 81.4%, 81.4% and 95% respectively considering culture as a gold-standard. MTBC negative culture samples (18.57%) showed positivity by LAMP assay as well as by qPCR. This study detected 7.69% non-tuberculous mycobacteria (NTM) by qPCR. All NTM positive samples were negative by TB-LAMP.TB-LAMP is an easy to perform, cost-effective, reliable assay with high sensitivity and specificity. World Health Organization recommended TB-LAMP as a rapid molecular test for rapid detection of tuberculosis and as replacement of microscopy in resource poor settings/hard to reach areas. Bangladesh being a high TB burden country it is essential to implement TB-LAMP to achieve End TB Strategy by 2035.

A Rare Case of Pulmonary Tuberculosis Masquerading as Laryngeal Tuberculosis or Malignant Manifestation

Introduction: Laryngeal tuberculosis (LTB) is usually accompanied by pulmonary tuberculosis (TB) involvement. Misdiagnosis often occurs because the symptoms are non-specific and resemble laryngeal malignancy. We reported a rare condition of pulmonary TB masquerading as larynx abnormalities such as malignant manifestations. Case: A 59-year-old man presented with a main complaint of prolonged hoarseness without clinical respiratory complaints. The patient additionally reported coughing as a symptom while receiving medical treatment in the hospital. A computed tomography (CT) scan of the neck without contrast revealed a glottic tumor invading the vocal cord – T3N2cMx. Laryngoscopy examination revealed T1-T1 tonsils. The pharyngeal mucosa was slightly hyperemic. The arytenoids and epiglottis were less hyperemic. There was no edema, the left vocal fold was paralyzed, could not be adducted, and there was a lump. The glottis rima gap was narrow, size 3–4 mm, and the mass could not be evaluated. Chest X-ray examination was normal, but rapid molecular tests of TB detected very low Mycobacterium tuberculosis (MTB) levels. The patient was treated with anti-TB treatment (ATT) according to body weight. An evaluation was performed after 2 weeks, and the patient's clinical and physical condition improved. Conclusion: Pulmonary TB patients in endemic countries can have clinical manifestations such as LTB or laryngeal malignancy in 1% of cases. The prognosis for LTB with pulmonary T involvement is quite good with ATT administration.

Diagnostic accuracy of truenat MTB plus for the detection of pulmonary and extrapulmonary tuberculosis

BackgroundThe diagnosis of Tuberculosis (TB) has been a challenge till the advent of rapid molecular diagnostic tests. The traditional diagnostic tests have its own limitations with regard to its performance or the turnaround time. Truenat MTB Plus assay, a battery-operated molecular assay developed in India has been introduced for its use in pulmonary TB (PTB). However, the diagnostic accuracy of the assay is not well studied in comparison with Mycobacterial culture, especially for extrapulmonary TB (EPTB). AimWe aimed at evaluating the diagnostic accuracy of Truenat MTB Plus assay for both PTB and EPTB comparing with culture for adult population. MethodsThe specimens from presumptive PTB and EPTB patients were processed for Truenat MTB Plus assay, solid or liquid culture and AFB staining. The electronic data of all the specimen reports collected retrospectively were analysed for the sensitivity and specificity. ResultsOut of the 736 samples which had valid culture reports, 364 (49.4 %) were respiratory and 372 (50.6 %) were extrapulmonary specimens. The test positivity rate for smear microscopy, Truenat MTB Plus assay and culture was 3.7 % (27), 8.2 % (60), 7.1 % (52) respectively. Of the 60 Truenat MTB Plus positive patients with TB, 33 (55 %) were PTB and 27 (45 %) were EPTB. We estimated overall sensitivity and specificity of Truenat MTB Plus as 90 % (95 % CI: 73.4–97.8) and 98. 2 (95 % CI:96–99.3) respectively for the detection of PTB. The overall sensitivity and specificity for EPTB was 81.8 % (95 % CI: 59.7–94.8) and 97.4 % (95 % CI: 95.1–98.8) respectively. ConclusionsTruenat MTB Plus assay has comparable diagnostic accuracy with other molecular assays. The Truenat MTB Plus assay can be used for the diagnosis of PTB and EPTB, especially in resource limited settings.

Overview of Tuberculosis: Causes, Symptoms and Risk Factors

Tuberculosis (TB) remains a global health threat, exacerbated by factors such as drug resistance, co-infections, and social determinants of health. This comprehensive review examines various aspects of TB, including epidemiology, pathophysiology, diagnosis, treatment, prevention, and control measures. The bacterium Mycobacterium tuberculosis causes TB and primarily affects the lungs, although it can also affect other organs. Risk factors for TB include poverty, malnutrition, overcrowded living conditions, and immunocompromised states such as HIV/AIDS. Symptoms of TB include cough, fever, weight loss, and night sweats, but can vary depending on the site of infection. Diagnosis typically involves clinical evaluation, imaging studies, and microbiological testing, with rapid molecular tests such as the Xpert MTB/RIF assay revolutionizing TB diagnostics. Treatment consists of multidrug therapy for six to nine months, with drug-resistant TB requiring longer and more complex regimens. Prevention and control efforts focus on early case detection, treatment adherence, infection control measures, and Bacille Calmette-Guérin (BCG) vaccine vaccination. TB research and innovation aim to develop new diagnostics, drugs, and vaccines to improve TB control and treatment outcomes. Challenges to TB control include stigma, healthcare access barriers, and the rise of drug-resistant TB strains. Collaboration and advocacy efforts are essential for addressing TB in special populations, high-risk settings, and co-infection scenarios. Integrating a One Health approach, harnessing technology, and addressing climate change impacts is critical for advancing TB control efforts and achieving the goal of ending the global TB epidemic.

An Overview of the Management of Drug-Resistant Tuberculosis in Six French-Speaking African Countries from 2018 to 2022.

Drug-resistant tuberculosis (DR-TB) poses a significant public health challenge, particularly in resource-limited settings. The prevalence and management of DR-TB in African countries require comprehensive strategies to improve patient outcomes and control the spread of the disease. Aggregated routine data (from 2018 to 2022) on multidrug-resistant TB (MDR-TB) were collected from the National TB Programs (NTPs) from all six countries. The diagnostic capacity for MDR-TB was globally insufficient. The system for collecting and transporting samples was sometimes inoperative. A total of 2353 cases of MDR-TB were reported, with 86.4% receiving treatment. The gap between the expected number of MDR-TB cases and the number reported per country varied from 51.5% to 88.0%, depending on the year. Fifty-two extensively drug-resistant (XDR) TB cases received treatment regimens over five years, with variations across countries. All patients received free follow-up examinations, nutritional and financial support for travel expenses to the outpatient care and treatment centers. The MDR-TB treatment success rates for all regimens between 2018 and 2021 ranged from 44.4 to 90.9%, varying by country and year. The information system relied on primary tools, reporting tools, and digital solutions. Progress has been made in MDR-TB management; however, challenges persist, necessitating resources to enhance access to rapid molecular screening tests.

Demographic and Clinical Factors Associated with Bacterial or Nonbacterial Etiologies of Acute Undifferentiated Febrile Illness: Findings from a 3-Year Observational Study in Thailand, 2017-2020.

Acute undifferentiated febrile illness (AUFI) is often undiagnosed in Thailand, resulting in delayed or ineffective treatment. We compared the demographic, exposure history, and clinical characteristics of AUFI patients with laboratory evidence of bacterial and nonbacterial pathogens. Patients aged 2-80 years presenting to 12 hospitals in Nakhon Phanom and Tak provinces were enrolled from April 2017 through May 2020. Interviews were conducted and blood, urine, and sputum were collected for culture as well as rapid diagnostic and molecular testing. A total of 1,263 patients tested positive for one or more bacterial, viral, or parasitic pathogens and were included in the analysis. Multivariable logistic regression was performed to compare factors associated with bacterial infections versus nonbacterial infections. Bacterial infections were more commonly identified in participants from Nakhon Phanom than Tak. Bacterial infections were independently associated with several factors including age ≥50 years (adjusted odds ratio [95% CI]): (4.18 [2.85-6.14]), contact with farm animals (1.82 [1.29-2.57]), antibiotic use within 72 hours of hospital presentation (2.37 [1.50-3.74]), jaundice (2.31 [1.15-4.63]), existing comorbidities (2.77 [1.93-3.96]), contact with febrile individuals (0.42 [0.31-0.57]), muscle pain (0.44 [0.31-0.64]), and rash (0.45 [0.29-0.70]). Bacterial infections were also associated with longer hospitalization (2.75 [2.08-3.64]) and lower odds of recovery at the time of discharge (0.14 [0.07-0.31]). Consideration of patient characteristics and signs/symptoms may help to inform targeted laboratory testing for suspected infectious etiologies. Understanding factors associated with bacterial and non-bacterial causes of AUFI may aid diagnosis and judicious use of antibiotics in resource-limited settings.

Early detection of bacteremia pathogens with rapid molecular diagnostic tests and evaluation of effect on intensive care patient management

İntroductionThe BioFire FilmArray Blood Culture Identification panel (BCID2), a rapid molecular blood culture identification test based on multiplex nested polymerase chain reaction. The aim of this study was to evaluate clinical outcomes between the period before (pre-BCID2 group) and after (post-BCID2 group) the introduction of the BCID2 panel into our routine practice. MethodsThe primary endpoint was time to optimal antibiotherapy, and the secondary endpoints were duration of hospital and intensive care unit stay, 7-day, 14-day and 28-day mortality rates after bacteremia. ResultsThe median time from empirical antibiotherapy to optimal antimicrobial therapy was 4560 (IQR;3060-7140) minutes in the pre-BCID2 group and 1715 (IQR;1362- 2776.25) minutes (in the post-BCID2 group (p<0.05). ConclusionAdding the BCID2 panel may improve antibiotic management in critically ill bacteremia patients

The Role of Rapid Molecular Tests, Whole-genome Sequencing, and Phenotypic Drug Susceptibility Testing in the Detection and Control of Drug-resistant Tuberculosis

The Role of Rapid Molecular Tests, Whole-genome Sequencing, and Phenotypic Drug Susceptibility Testing in the Detection and Control of Drug-resistant Tuberculosis

The Performance of GeneXpert in the Diagnosis of Lymph Node Tuberculosis: A Prospective Study Comparing GeneXpert and Culture Findings.

Background and objective Lymph node tuberculosis (LNTB) is a common manifestation of extrapulmonary tuberculosis (EPTB). GeneXpert is a rapid diagnostic molecular test that simultaneously detects tuberculosis and rifampicin (RIF) resistance. In this study, we aimed to assess the epidemiology of LNTB and diagnostic performance parameters of the GeneXpert in routineENT practice. Methods We conducted a cross-sectional prospective study from January to July 2019,in the Department of Otorhinolaryngology and Head Neck Surgery at the Hassan II University Hospital Center of Fez, Morocco. The samples were collected using lymph node biopsy and subjected to GeneXpert assay, culture, and histopathology. Diagnostic performance parameters of the GeneXpert were calculated and compared with culture. Results All patients with cervical adenopathy were included. Lymph node biopsies were performed for all patients. The performance of the GeneXpert was assessed according to culture findings. Among the 75 cases, the mean age was 21.6 ± 12.7 years with a female predominance (60%). GeneXpert was positive in 66.7% of specimens. The sensitivity and specificity of the GeneXpert assay were 78.6% and 40.4% respectively. GeneXpert accuracy was 54.6%. The positive predictive value (PPV) and negative predictive value (NPV) were found to be 44% (95% CI: 30.2-57.8) and 76% (95% CI: 59.3-92.7) respectively. Mycobacterium bovis was isolated in all samples, with no case of resistance to RIF found. Conclusions The performance of GeneXpert was found to be superior in terms of establishing the diagnosis of LNTB. It offers speedy and prompt results and clinicians should adopt it in routine clinical practice.

Overview of rapid molecular test (RMT)–gene xpert mtb/rif ultra results in pulmonary tuberculosis patients based on the history of therapy

Overview of rapid molecular test (RMT)–gene xpert mtb/rif ultra results in pulmonary tuberculosis patients based on the history of therapy

The Molecular Mouse System: A New Useful Tool for Guiding Antimicrobial Therapy in Critically Ill Septic Patients.

Bloodstream infections (BSI) caused by multidrug-resistant (MDR) bacteria, pose a major threat for patients, especially for those who are immunosuppressed. Rapid pathogen detection and characterization from positive blood cultures are crucial in the management of patients with BSI to enable an adequate and timely antimicrobial therapy. This study aimed to investigate the potential role of the Molecular Mouse system, a new CE IVD molecular test designed to rapidly detect the causative agents of bacteremia and their resistance determinants, in the management of the therapy in critically ill patients. Agreement between the results of the Molecular Mouse and the conventional routine method was also considered. Overall, 100 positive blood cultures were collected from septic critically ill patients from May 2023 to January 2024 and analyzed with Molecular Mouse and routine protocols. The new instrument consistently agreed with the routine protocols in the case of monomicrobial blood cultures, while some discrepancies were obtained in the polymicrobial samples. Antimicrobial resistance genes were detected in 35 samples, with vanA and CTX-M-1/9 groups being the most frequently detected targets. Therapy was adjusted in 42 critically ill patients confirming the importance of new rapid molecular tests in the management of positive blood cultures, to adjust empirical therapy and use new antibiotics accurately.

Does the Addition of Point-of-Care Testing Alter Antibiotic Prescribing Decisions When Patients Present with Acute Sore Throat to Primary Care? A Prospective Test of Change.

Accurate clinical diagnosis of patients presenting to primary care settings with acute sore throat remains challenging, often resulting in the over-prescribing of antibiotics. Using point-of-care tests (POCTs) to differentiate between respiratory infections is well-accepted, yet evidence on the application within primary care is sparse. We assessed the application of testing patients (n = 160) from three family practices with suspected Streptococcal infections using rapid molecular tests (ID NOW Strep A2, Abbott). In addition to comparing clinical evaluation and prescription rates with either usual care or testing, patients and staff completed a questionnaire about their experience of molecular POCT in primary care. The immediate availability of the result was important to patients (100%), and staff (≈90%) stated that molecular testing improved the quality of care. Interestingly, only 22.73% of patients with a Centor score > 2 tested positive for Strep A and, overall, less than 50% of Centor scores 3 and 4 tested positive for Strep A with the ID NOW testing platform. The addition of rapid molecular POCTs to clinical assessment resulted in a 55-65% reduction in immediate and deferred antibiotic prescriptions. The intervention was popular with patients and medical staff but was associated with increased cost and a longer appointment length.

Universal and Expanded Screening Strategy for Congenital Cytomegalovirus Infection: Is Pool Testing by a Rapid Molecular Test in Saliva a New Choice in Developing Countries?

Background: Several screening strategies for identifying congenital CMV (cCMV) have been proposed; however, the optimal solution has yet to be determined. We aimed to determine the prevalence of cCMV by universal screening with saliva pool testing and to identify the clinical variables associated with a higher risk of cCMV to optimize an expanded screening strategy. Methods: We carried out a prospective universal cCMV screening (September/2022 to August/2023) of 2186 newborns, analyzing saliva samples in pools of five (Alethia-LAMP-CMV®) and then performed confirmatory urine CMV RT-PCR. Infants with risk factors (small for gestational age, failed hearing screening, HIV-exposed, born to immunosuppressed mothers, or &lt;1000 g birth weight) underwent expanded screening. Multivariate analyses were used to assess the association with maternal/neonatal variables. Results: We identified 10 infants with cCMV (prevalence: 0.46%, 95% CI 0.22–0.84), with significantly higher rates (2.1%, 95% CI 0.58–5.3) in the high-risk group (p = 0.04). False positives occurred in 0.09% of cases. No significant differences in maternal/neonatal characteristics were observed, except for a higher prevalence among infants born to non-Chilean mothers (p = 0.034), notably those born to Haitian mothers (1.5%, 95% CI 0.31–4.34), who had higher odds of cCMV (OR 6.82, 95% CI 1.23–37.9, p = 0.04). Incorporating maternal nationality improved predictive accuracy (AUC: 0.65 to 0.83). Conclusions: For low-prevalence diseases such as cCMV, universal screening with pool testing in saliva represents an optimal and cost-effective approach to enhance diagnosis in asymptomatic patients. An expanded screening strategy considering maternal nationality could be beneficial in resource-limited settings.

Spinal Osteoarticular Multidrug-resistant Tuberculosis (MDR/RR-TB) in a Child: A Case Report

Introduction We report a case of a young child with multidrug-resistant tuberculosis (MDR/RR-TB) of the thoracic spine, complicated by myelopathy. Case Report Clinical assessment revealed a lower thoracic gibbus and neurological features of upper motor neuron syndrome conforming to myelopathy. Radiological evaluation revealed a marked kyphosis, contiguous T10-T11 vertebral destruction, paraspinal soft tissue collection, and intraspinal compression with cord signal changes, suggestive of spinal TB. Rapid molecular testing expedited the diagnosis of MDR/RR-TB and guided prompt treatment initiation. Although second-line drugs are the mainstay of treatment, surgery was undertaken due to marked kyphosis, spinal instability, and neurological complications in the growing spine. Conclusion Although the case seems interesting, it, unfortunately, highlights multiple health system failures in developing countries, resulting in premature termination of MDR/RR-TB treatment and loss of kyphosis correction with subsequent recurrence of the kyphotic deformity.

Molecular and phenotypic identification of bacterial species isolated from cows with mastitis from three regions of Poland

BackgroundBovine mastitis is a widespread disease affecting dairy cattle worldwide and it generates substantial losses for dairy farmers. Mastitis may be caused by bacteria, fungi or algae. The most common species isolated from infected milk are, among others, Streptococcus spp., Escherichia coli, Staphylococcus aureus and non-aureus staphylococci and mammaliicocci. The aim of this paper is to determine the frequency of occurrence of bacterial species in milk samples from cows with mastitis from three regions of Poland: the north-east, the south-west and the south. To this end 203 milk samples taken from cows with a clinical form (CM) of mastitis (n = 100) and healthy animals (n = 103) were examined, which included culture on an appropriate medium followed by molecular detection of E. coli, S. aureus, Streptococcus agalactiae and Streptococcus uberis, as one of the most common species isolated from mastitis milk.ResultsThe results obtained indicated that S. uberis was the most commonly cultivated CM species (38%, n = 38), followed by S. aureus (22%, n = 22), E. coli (21%, n = 21) and S. agalactiae (18%, n = 18). Similar frequencies in molecular methods were obtained for S. uberis (35.1%) and S. aureus (28.0%). The variation of sensitivity of both methods may be responsible for the differences in the E. coli (41.0%, p = 0.002) and S. agalactiae (5.0%, p = 0.004) detection rates. Significant differences in composition of species between three regions of Poland were noted for E. coli incidence (p < 0.001), in both the culture and molecular methods, but data obtained by the PCR method indicated that this species was the least common in north-eastern Poland, while the culture method showed that in north-eastern Poland E. coli was the most common species. Significant differences for the molecular method were also observed for S. uberis (p < 0.001) and S. aureus (p < 0.001). Both species were most common in southern and south-western Poland.ConclusionsThe results obtained confirm the need to introduce rapid molecular tests for veterinary diagnostics, as well as providing important epidemiological data, to the best of our knowledge data on Polish cows in selected areas of Poland is lacking.

Polymerase Chain Reaction (PCR) Profiling of Extensively Drug-Resistant (XDR) Pathogenic Bacteria in Pulmonary Tuberculosis Patients.

Introduction Pulmonary tuberculosis (TB) remains a global health concern, exacerbated by the emergence of extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis. This study employs advanced molecular techniques, specifically polymerase chain reaction (PCR) profiling, to comprehensively characterize the genetic landscape of XDR pathogenic bacteria in patients diagnosed with pulmonary TB. The objective of the study is to elucidate the genes that are associated with drug resistance in pulmonary TB strains through the application of PCR and analyze specific genetic loci that contribute to the development of resistance against multiple drugs. Materials and methods A total of 116 clinical samples suspected of TB were collected from the tertiary healthcare setting of Saveetha Medical College and Hospitals for the identification of MTB, which includes sputum (n = 35), nasal swabs (n = 17), blood (n = 44), and bronchoalveolar lavage (BAL) (n = 20). The collected specimens were processed and subjected to DNA extraction. As per the protocol, reconstitution of the DNA pellet was carried out. The reconstituted DNA was stored at -20 °C for the PCR assay. From the obtained positive sample specimens, XDR pulmonary TB specimens were focused on the targeted genes, specifically the rpoB gene for rifampicin resistance, inhA, and katG gene for thepromoter region for isoniazid resistance. Results Out of a total of 116 samples obtained, 53 tested positive for pulmonary TB, indicative of a mycobacterial infection. Among these positive cases, 43 patients underwent treatment at a tertiary healthcare facility. Subsequently, a PCR assay was performed with the extracted DNA for the target genes rpoB, inhA, and katG. Specifically, 22 sputum samples exhibited gene expression for rpoB, inhA, and katG, while nine nasal swabs showed expression of the rpoB and inhA genes. Additionally, rpoB gene expression was detected in seven blood specimens, and both rpoB and inhA genes were expressed in five BAL samples. Conclusion The swift diagnosis and efficient treatment of XDR-TB can be facilitated by employing advanced and rapid molecular tests and oral medication regimens. Utilizing both newly developed and repurposed anti-TB drugs like pretomanid, bedaquiline, linezolid, and ethionamide. Adhering to these current recommendations holds promise for managing XDR-TB effectively. Nevertheless, it is significant to conduct well-designed clinical trials and studies to further evaluate the efficacy of new agents and shorter treatment regimens, thus ensuring continuous improvement in the management of this challenging condition.

Rapid resistance detection is reliable for prompt adaptation of isoniazid resistant tuberculosis management

ObjectivesAppropriate tuberculosis (TB) management requires anti-TB drugs resistance detection. We assessed the performance of rapid resistance detection assays and their impact on treatment adaptation, focusing on isoniazid resistant (Hr) TB. MethodsFrom 2016 to 2022, all TB cases enrolled in 3 hospitals were reviewed for phenotypic drug susceptibility testing (p-DST) and genotypic DST (g-DST) performed by rapid molecular testing, and next generation sequencing (NGS). Clinical characteristics, treatment and outcome were collected for Hr-TB patients. The concordance between g-DST and p-DST results, and delay between treatment initiation and results of g-DST and p-DST were respectively recorded to assess the contribution of DST results on Hr-TB management. ResultsAmong 654 TB cases enrolled, 29 were Hr-TB. Concordance between g-DST by rapid molecular methods and p-DST was 76.9 %, whilst concordance between NGS-based g-DST and p-DST was 98.7 %. Rapid resistance detection significantly fastened Hr-TB treatment adaptation (median delay between g-DST results and treatment modification was 6 days). It consisted in fluoroquinolone implementation for 17/23 patients; outcome was favourable except for 2 patients who died before DST reporting. ConclusionRapid resistance detection fastened treatment adaptation. Also, NGS-based g-DST showed almost perfect concordance with p-DST, thus providing rapid and safe culture-free DST alternative.