Bacteriological Culture Research Articles

ПРИНЦИПЫ ПРОФИЛАКТИРОВАНИЯ АНТИБИОТИКОРЕЗИСТЕНТНОСТИ ПРИ ЛЕЧЕНИИ УРОЛОГИЧЕСКОГО СИНДРОМА КОШЕК

The article presents data on the occurrence of urological syndrome in cats of different age and gender groups and the structure of diseases of the lower urinary tract, leading to its development. The most frequently detected pathology was idiopathic feline cystitis (IFC) 82.3 %, urocystolithiasis and bacterial cystitis were less frequently detected – 10.3 % and 7.4 %, respectively. In the differential diagnosis of recurrent cystitis by bacteriological seeding of urine, it was found that more often the cause of the resumption of dysuria was IFC – 73.7 % of negative urine seeding. In other cases, the bacterial etiology of bladder inflammation was confirmed and uropathogens were identified: E. faecalis, E. faecium – 10.5 %, P. mirabilis – 5.3 % of results. When diagnosing cystitis in cats, the following algorithm should be followed: the primary instrumental diagnostic method is ultrasound (the fact of cystitis is established: thickening of the bladder wall, changes in its structure, the presence of suspension and / or concretions in the organ cavity), to differentiate the etiology of cystitis, it is necessary to use laboratory diagnostic methods – general analysis and bacteriological urine culture. Drug treatment consisted of anesthesia (idiopathic cystitis), and in case of septic cystitis, etiotropic therapy was additionally prescribed. Analgesia was carried out in a complex with the use of drugs from the group of nonsteroidal anti-inflammatory drugs (NSAIDs) – meloxicam 0.05 mg/kg 1 time per day and alpha-blockers – terazosin as an antispasmodic at a dose of 0.5 mg /cat 2 times a day. Antibacterial therapy was used strictly according to the results of bacteriological urine culture: the first–line drug of choice was used – amoxicillin with clavulanic acid, reserve antibiotics – cefixime, marbofloxacin; dosages, frequency of administration per day, the course of treatment was prescribed to each patient individually, according to the diagnostic results. The algorithm of actions of a veterinarian when working with cystitis in cats, developed during this study, will help to avoid uncontrolled use of antibiotics, and, as a consequence, the development of antibiotic resistance

Leptospirose genital bovina: achados em touros mantidos em condições do bioma Caatinga

ABSTRACT: Leptospirosis is a disease that causes economic and social impact, as it affects wild and domestic animals and humans. There may be peculiarities in the epidemiology of this disease in the Caatinga biome, Brazil, where the environment is adverse and the etiologic agent, Leptospira spp., requires alternative transmission routes. Considering that in bovine leptospirosis the genital carrier is constantly neglected and the lack of reports on the role of bulls in the epidemiology of the bovine genital leptospirosis (BGL) syndrome, mainly in semiarid conditions such as Caatinga biome, this study aimed to investigate bulls maintained in Caatinga biome conditions as genital carriers of leptospires. Urinary tract (urine, bladder, and kidney) and reproductive tract (vas deferens, cauda epididymis, and vesicular gland) samples were collected from 42 slaughtered bulls. Microscopic agglutination test (MAT), polymerase chain reaction (PCR), and microbiological isolation were included as diagnostic methods. Anti-Leptospira spp. antibodies were found in 17 (40.48%) animals, while 26 animals (61.90%) had at least one organ or urine with leptospiral DNA, and 10 animals (23.81%) were positive at bacteriological culture. Sequenced samples targeting the LipL32 gene showed 99% similarity with Leptospira borgpetersenii. Molecular analysis of samples from the vas deferens and cauda epididymis is recommended for the diagnosis of genital leptospirosis in bulls and, if it is impossible to collect these tissues, semen can be used. In conclusion, this study provides important information relating to bulls from the Caatinga biome, Brazil, as carriers of genital leptospirosis. The results indicate that, even under adverse environmental conditions, leptospires may survive and propagate, mainly due to the characteristic of genital carriers for the sexually spreading of adapted Leptospira species without influence by external variables. Thus, prevention and control strategies for bovine leptospirosis need to include actions aimed at the genital carrier.

Новые подходы к ведению пациентов с нестойкой ремиссией круглогодичного аллергического ринита на фоне персистирующей хламидийной инфекции

Currently, allergic rhinitis is a global socioeconomic problem. According to current statistics, from 15 to 30% of the world’s population suffers from year-round or seasonal allergic rhinitis. Increasingly, the attention of Russian clinicians is attracted by the problem of year-round allergic rhinitis as there is an increase in the incidence in patients of the central zone of the Russian Federation with this form of rhinitis due to sensitization to house dust mite allergens, epidermal allergens of domestic animals, insect and mold allergens. Despite a timely diagnosis and received basic treatment, patients suffering from year-round allergic rhinitis often fail to achieve stable remission. Therefore, we can conclude that a more thorough diagnosis of the disease is needed, aimed at identifying other factors that affect the course of the disease. Objective. To develop a scheme for diagnosing a possible persistent respiratory chlamydial infection that affects the course of year-round allergic rhinitis in patients with a tendency to transient remissions. Materials and methods. Computed tomography of the paranasal sinuses, nasal swab for flora, PCR scraping of the nasal mucosa for the detection of Epstein–Barr virus (EBV) DNA, determination of viral DNA of cytomegalovirus infection (CMV) (PCR scraping of the nasal mucosa), determination of DNA in the scraping of epithelial cells of the nasal mucosa (PCR scraping) of human herpes virus type 6 (HHV-6 type). Patients who had pathological changes in computed tomography of the paranasal sinuses, deviations from the normal flora during bacteriological culture, and positive results in the PCR study of the above infections were excluded from the study. Then, PCR scraping of the nasopharyngeal mucosa for the detection of chlamydia pneumoniae, a survey of complaints (SNOT-22 questionnaire), data from an objective examination method (examination of ENT organs using video endoscopic technologies), an immunological examination of blood serum for IgG antibodies to chlamydial infection, further avidity of IgG antibodies to chlamydia pneumoniae and serum IL-6. Conclusion. The proposed diagnostic scheme will allow identifying a possible persistent respiratory chlamydial infection, which is the cause of transient remission of year-round allergic rhinitis, and developing a new integrated approach to the management of patients with year-round allergic rhinitis associated with this infection.

Ocorrência de Salmonella spp. em amostras fecais de potros com e sem diarreia no estado de São Paulo: diagnóstico microbiológico, perfil de susceptibilidade aos antimicrobianos e detecção molecular

ABSTRACT: The present study investigated Salmonella spp. in the feces of 200 foals up to one year of age (100 with clinical signs of diarrhea and 100 without clinical signs of diarrhea). Bacteriological culture, serotyping, antimicrobial susceptibility, and real-time PCR (qPCR SYBR® Green or a TaqMan®) for detecting the invA gene (with and without a selective pre-enrichment step in tetrathionate broth) were performed. Bacterial culture revealed 15% (n=30) of positive animals (21 animals with diarrhea and nine without diarrhea). Among the 30 isolates, 13 different serovars were identified: S. Infantis, S. Minnesota, S. I.4,5,12:i:-; S. Anatum, S. Cerro, S. Oranienburg, S. Braenderup, S. Give, S. Newport, S. IIIb 61:c:z35, S. 109:-:1.5, S. I.4.12:d:-, S. I.6.8:-:-. Multidrug resistance was found in 43.33% (n=13) of the isolates, with one isolate obtained from animals without diarrhea and 12 isolates from animals with diarrhea. All qPCR techniques used in the study classified more samples as positive for Salmonella spp. than the bacterial culture of feces. In addition, all qPCR techniques detected more positive animals in the diarrhea group than in the diarrhea-free group. The results confirm the utility of the qPCR method without the pre-enrichment step in tetrathionate as a rapid test for Salmonella spp. in carrier animals. In animals with clinical signs of diarrhea, it can be combined with bacterial culture (antimicrobial susceptibility testing and serotyping). The isolation of Salmonella spp. in nine animals without diarrhea confirms the importance of asymptomatic carrier animals in the epidemiology of the disease. The multidrug resistance observed highlights the importance of rational antimicrobial use in horses and adopting biosecurity protocols that are efficacious in controlling the spread of infections between animals and zoonotic transmission in farms.

Comparative analysis of diagnostic methods and risk factors for Aelurostrongylus abstrusus infection in brazilian cats

Abstract This study aimed to prospectively evaluate the risk factors of infection by Aelurostrongylus abstrusus in Brazilian cats with cough and/or radiographic changes, using as diagnostic tools the Baermann method (BM), polymerase chain reaction (PCR) of feces, bronchoalveolar lavage fluid (BALF), and cytology. Forty-three cats that were presented with cough or lung radiographic abnormalities compatible with bronchoalveolar disease were included in the study. After clinical evaluation, feces samples were collected to investigate lungworm parasitism through BM and PCR. BALF was performed to provide samples for cytology, bacteriology, and fungal culture. Stool PCR was considered the gold standard for diagnosis tests, and the other methods were evaluated by their agreement. PCR presented 74% (32/43) of positivity for A. abstrusus, while in the BM, 41% (18/43) were positive. BM showed sensitivity of 56.25% and specificity of 100% when compared with PCR. No larva was found in the cytological evaluation of 21 BALF samples. Lungworm is an important cause of bronchopulmonary disease in domestic cats in Brazil and should be included as a differential diagnosis when a cat is presented with cough or radiographic abnormalities. BM is a sensitive, non-invasive, and cheap technique to diagnose the disease, but it is not as sensitive as PCR.

Prevalence of Pathogenic Intestinal Parasites and Enteropathogenic Bacteria in Faecal Samples Obtained from Abattoirs in Ogbomoso, Oyo State, Nigeria

This study was undertaken to determine the prevalence of intestinal parasites and enteropathogenic bacteria in fecal effluents from abattoir. A total of 162 samples were examined out of which 70 faecal samples were collected from cow, 35 from pig, 35 from goat and 22 from sheep. These samples were processed using standard parasitological techniques ( macroscopy, microscopy; the Formol-ether concentration technique and zinc sulphate floatation technique) and bacteriological (culture, Gram reaction and biochemical characterization). Data was analyzed using Chi-square test. One hundred and eleven (111) samples were found positive with one or more parasites giving an overall prevalence of 68.5%. Pigs recorded the highest prevalence of 77.1% for intestinal parasites, followed by goat and cow with prevalence of 68.6% and 65.7% respectively and the least prevalence was observed in sheep, 63.6%. The prevalence of different parasites encountered include Fasciolopsis buski (8.6%), Hookworm (8.0%), Ascaris suum (7.4%), Balantidium coli (7.4%), Fasciola hepatica (7.4%), Entamoeba histolytica (7.4%), Taenia species (6.2%), Fasciola gigantica (4.3%) and Toxocara species (1.2%). Mixed infections of Balantidium coli+Entamoeba histolytica has the highest frequency of 4(2.5%) followed by Entamoeba histolytica+Hookworm and Toxocara species+Balantidium coli with the frequency of 3(1.9%) each, Ascaris suum+Taenia species, Ascaris suum+Taenia species+Hookworm and Balantidium coli+Fasciola hepatica with a frequency of 2(1.2%) each and Toxocara species+Balantidium coli recorded the lowest frequency of 1(0.6%). Also the prevalence of potentially pathogenic bacteria and yeast cells encountered include Bacillus species (29.6%), Escherichia coli (23.5%), Campylobacter species (17.3%), Pseudomonas aeruginosa (11.1%), Staphylococcus aureus (10.5%), Yeast cells (4.9%) and Staphylococcus species (3.1%). This study shows high degrees of fecal contamination of intestinal parasites and bacterial agents. As a result of this sanitary measures and Government policy should be strictly employed as this will go a long way to help check environmental contamination and reduce potential risks posed by these pathogens.

РОЛЬ БАКТЕРИОЛОГИЧЕСКОГО И БАКТЕРИОСКОПИЧЕСКОГО ИССЛЕДОВАНИЯ МОЧИ В ДИАГНОСТИКЕ ИНФЕКЦИЙ МОЧЕВЫХ ПУТЕЙ

The article presents the results of comparative urine studies of patients with pyelonephritis and patients without signs of UTI. The results of bacterioscopic and bacteriological examination of urine of 69 patients with pyelonephritis and 27 without UTI were analyzed. A high prevalence of negative urine culture in pyelonephritis (59.4%) was revealed, as well as the prevalence of negative culture in the presence of bacteriuria detected microscopically in urine sediment (37.5%). In patients without pyelonephritis, a bacteriological study showed bacterial growth in 66.7% of cases, which indicates the prevalence of asymptomatic bacteriuria in urological patients. Literature data on diagnostic problems and possible causes of false negative results of bacteriological examination in UTI are analyzed. One of the reasons for these results are the disadvantages and limitations of standard bacteriological culture. The need to introduce new advanced methods of bacteriological research into clinical practice is urgent.

The effect of antibiotic versus no treatment at dry-off on udder health and milk yield in subsequent lactation: A retrospective analysis of Austrian health recording data from dairy herds.

Bovine mastitis is the most commonly diagnosed disease of dairy cows worldwide and causes extensive economic losses to milk producers. Intramammary infection status before dry-off plays a decisive role with respect to udder health and milk yield in the subsequent lactation. The aim of this study was to compare the effect of antibiotic dry cow therapy (DCT) versus no treatment at dry-off on milk yield, somatic cell count (SCC), inflammation of the mammary gland (IMG), and the incidence of clinical mastitis in the subsequent lactation. Dairy herd data from 251 Austrian dairy farms were recorded over an observation period of 12 mo and subsequently analyzed. The data set included 5,018 dairy cows: 2,078 were treated with antibiotics (abDCT group) and 2,940 were not treated (noDCT group) at dry-off. The abDCT group was subdivided, based on the antimicrobial active substances used for drying off, into 4 different groups (penicillins, cloxacillin, cephalosporins, and rifaximin). Based on bacteriological culture results, infections were grouped into those caused by major, minor, and other pathogens. Additionally, the IMG was defined via SCC from milk recording data using a cutoff of 200,000 cells/mL before drying off and after calving. The incidence of clinical mastitis cases within 30 and 90 d in milk was calculated using veterinary diagnosis data. To investigate the effect of different dry cow therapies on the following parameters: milk yield, SCC, and diagnosed clinical mastitis cases, different linear mixed models were constructed. Overall, the abDCT group was determined to have a significantly higher milk yield over 305 d in milk in the subsequent lactation (increase of 6.18%), compared with the noDCT group (increase of 4.29%). Both groups (abDCT and noDCT) demonstrated a decrease in the first SCC after calving compared with the SCC before dry-off, although the treated cows had a significantly higher reduction. Regarding the different antibiotic groups, with exception of the rifaximin treated cows, all antibiotic groups showed a significant difference from not treated cows with respect to SCC. Additionally, we were able to demonstrate that cows with IMG before dry-off had a 2.073 times higher chance of an increased SCC (>200,000 cells/mL) after calving. With respect to the veterinary diagnosis data, neither the IMG before drying off nor the type of DCT had a significant influence on the probability of developing clinical mastitis within 30 or 90 d in milk. Only a small number of treatments was accompanied with a bacteriological examination before drying off. However, the existing data in this study indicates that the intramammary infection status before dry-off in combination with different dry cow treatments influences udder health and milk yield after calving. Nevertheless, further studies with larger data sets of bacteriological examinations are necessary to enable a more in-depth investigation into the effects of different antibiotic substances used for DCT.

Bacteriospermia among smallholder artificial insemination boars in the Philippines and potential associated factors

Objective: To determine the prevalence of bacteriospermia, the bacterial load, and the potential factors associated with bacterial contamination in boar semen collected by local smallholder artificial insemination operators. Methods: Fifteen individual raw semen samples were collected from locally available artificial insemination boars owned by different smallholder boar operators within the 5th district of Leyte, Philippines and were subjected to standard bacteriological culture and identification, including a survey of potentially associated factors. Prevalence and bacterial count were determined accordingly, while boar characteristics and collection practices were clustered following agglomerative hierarchical clustering technique. Results: One hundred percent contamination with a bacterial count of (2.01±0.38)×103 CFU/mL was observed. At least 73.33% of the samples were positive for Bacillus spp., while other identified isolates included Enterobacter spp., Staphylococcus spp., E. coli, Pseudomonas spp., Citrobacter spp., and Klebsiella spp. Conclusions: Despite the high prevalence of bacteriospermia, the bacterial count is low. Nevertheless, on-farm practices on boar health and management, semen collection, and sanitation as well as the enhancement of basic protocols to control contamination should be conscientiously considered in smallholder artificial insemination operation.

Clinical presentation, treatment, and outcome of 24 dogs with bacterial meningitis or meningoencephalitis without empyema (2010-2020).

Bacterial meningitis (BM) and meningoencephalitis (BMEM) are associated with high case fatality rates and neurologic sequelae in people, but limited data exists on outcome in dogs. To report the clinicopathologic features, treatment and outcome of BM/BMEM in dogs, with a focus on clinical presentation, relapse and long-term neurological deficits. Twenty-four client-owned dogs diagnosed with BM/BMEM without empyema. Retrospective case series of dogs diagnosed with BM/BMEM from 5 veterinary referral hospitals between January 2010 and August 2020. Twenty-four dogs were included. Median duration of clinical signs was 2 days (range ≤24 hours to 30 days) and signs recorded included pyrexia (3) and cervical hyperesthesia (10). Neurological deficits were present in 18 dogs including altered mentation (12), ataxia (8), nonambulatory status (8), head tilt (8), and cranial nerve deficits (13). Intracellular bacteria were visualized on cerebrospinal fluid (CSF) analysis in 15/24 dogs, with positive CSF bacteriological culture in 8/21. Otitis media/interna (OMI) was diagnosed in 15/24 dogs, of which 6/15 dogs underwent total ear canal ablation and lateral bulla osteotomy. Twenty dogs survived to hospital discharge. Median duration of antibiotic administrations was 8 weeks (range, 2-16 weeks). Glucocorticoids were administered to 15 dogs. Median follow-up time was 92 days (range, 10-2233 days). Residual neurological deficits were reported in 9 dogs, with a single case of suspected relapse. Clinical signs were variable in dogs with BM/BMEM, the nidus of bacterial infection was often OMI and the majority of dogs made a full recovery with treatment.

Tracking Annual Antimicrobial Resistance at a Tertiary Care Hospital amidst Raging COVID-19 Pandemic

Background: Timely preparation and presentation of the annual cumulative antibiogram play an important role in the dissemination of an updated susceptibility pattern to clinicians and thus aid in the appropriate choice of antimicrobials for empirical therapy while minimizing adverse effects and resistance. The study aimed to present and analyze the annual AMR data that may be helpful in designing antibiotic policy. Methods: All clinical specimens routinely submitted to the Department of Microbiology from January to December 2021 for bacteriological culture and antimicrobial susceptibility testing (AST) were included. AST was performed for pathogenic isolates by disc diffusion/agar dilution/broth microdilution methods/VITEK® 2 compact system. All data were entered and analyzed using WHONET 2020 software. Results: A total of 46,629 routine specimens were processed, yielding 5792 non-repeat bacterial isolates. Relatively fewer specimens were received during the first few months when the hospital catered exclusively to COVID-19 patients. The most common bacterial isolates were Escherichia coli (30%), Staphylococcus aureus (21%), Klebsiella sp. (18%), Pseudomonas sp. (10%), Acinetobacter sp. (8%) and Enterococcus sp. (5%). Analysis showed low susceptibility to 3rd generation cephalosporins, fluroquinolones, and cotrimoxazole among Gram negative bacteria. Less than 50% Acinetobacter sp. were carbapenem susceptible. We report high rate of methicillin resistance in S. aureus (74%). Overall susceptibility was much lower in specimens from ICU followed by in-patients and out-patients. Conclusion: Antimicrobial resistance is rapidly assuming the proportions of a pandemic, with several authors calling it “invisible” pandemic. As is evident from the present study, low susceptibilities to all but a few last-resort drugs are leaving few choices for treatment. This mandates effective preparation, distribution, and presentation of annual antibiograms, which will help in formulating hospital antibiotic policy.

Bacterial identification in cerebrospinal fluid of domestic species with neurologic signs: a retrospective case-series study in 136 animals (2005-2021).

Central nervous system (CNS) infections comprise life-threatening clinical conditions in domestic species, and are commonly related to severe sequelae, disability, or high fatality rates. A set of bacterial pathogens have been identified in central nervous infections in livestock and companion animals, although the most of descriptions are restricted to case reports and a lack of comprehensive studies involving CNS-related bacterial infections have been focused on a great number of domestic species. In this scenario, we retrospectively investigated selected epidemiological data, clinical findings, bacteriological culture, and in vitro susceptibility patterns of 136 nonrepetitive neurologic cases in domestic species (2005-2021). Bacterial isolates were recovered from 25% (34/136) of the cerebrospinal fluid (CSF) sampled. The isolates were obtained from cattle (9/136 = 6.6%), dogs (7/136 = 5.1%), horses (6/136 = 4.4%), goats (3/136 = 2.2%), pigs (3/136 = 2.2%), sheep (3/136 = 2.2%), cats (2/136 = 1.5%), and asinine (1/136 = 0.7%). Among animals with bacterial isolation, Staphylococcus aureus (6/34 = 17.6%), Escherichia coli (5/34 = 14.7%), Staphylococcus beta-hemolytic (5/34 = 14.7%), and Trueperella pyogenes (3/34 = 8.8%) were predominant, in addition to a miscellaneous of other bacteria isolated in minor frequency, e.g., Corynebacterium pseudotuberculosis, Enterobacter cloacae, Mannheimia haemolytica, Pseudomonas aeruginosa, and Streptococcus equi subsp. equi. In vitro susceptibility tests of isolates revealed that amoxicillin/clavulanic acid (11/13 = 84.6%), cephalexin (9/11 = 81.8%), and florfenicol (9/12 = 75%) were the most effective antimicrobials. Conversely, isolates exhibited resistance mainly to tetracycline (6/10 = 60%), penicillin (6/11 = 54.5%), and trimethoprim/sulfamethoxazole (5/11 = 45.5%). Also, multidrug resistance to ≥ 3 classes of antimicrobials was found in 23.5% (8/34) strains. Data relative to the outcome was available in 79.4% (27/34) of animals that had bacterial isolation, and from these, the lethality rate was 92.6% (25/27). Incoordination (14/34 = 41.2%), recumbency (11/34 = 32.4%), apathy (10/34 = 29.4%), anorexia (9/34 = 26.5%), blindness (7/34 = 20.6%), seizure (6/34 = 17.6%), limb paresis (5/34 = 14.7%), head-pressing (4/34 = 11.8%), and nystagmus (3/34 = 8.8%) were the most frequent clinical signs. A variety of bacterial pathogens were identified in the CSF of domestic species showing neurologic signs, with a predominance of staphylococci, streptococci, and enterobacteria. High lethality of cases, poor in vitro efficacy of conventional antimicrobials, and a high in vitro multidrug resistance pattern of isolates were seen. Our results contribute to etiological characterization, antimicrobial resistance patterns, and clinical-epidemiological findings of bacterial infections in domestic species with neurological signs.

Bovine campylobacteriosis in bulls: insights in the conventional and molecular diagnosis.

Campylobacter fetus is a gram-negative motile bacterium, with two subspecies relevant to cattle health: C. fetus subsp. venerealis (Cfv) and C. fetus subsp. fetus (Cff). Both subspecies are associated with reproductive losses in cattle. In this study, we evaluated the identification of C. fetus for the diagnosis of bovine campylobacteriosis through bacteriological culture, direct immunofluorescence (DIF) and molecular tests in preputial smegma (PS) samples of three Angus bulls challenged with Cfv, Cfv biovar intermedius (Cfvi) or Cff, respectively, in an experiment imitating the natural infection. Two DNA extraction protocols were tested (in-house thermal extraction and commercial kit). Aspiration and scraping collection for PS were compared by conventional tests. Additionally, bacteremia was also evaluated in blood samples. Bulls were challenged by natural mating with heifers that had been experimentally infected with C. fetus subspecies; which led to infection. The Cfv- and Cfvi-bulls were positive for at least 9 months. Although Cff is not considered a venereal strain, in this study it was transmissible to bull from heifers experimentally infected, as evidenced by its colonization and persistence in the preputial cavity for 5 to 6 months. This finding suggests a potential risk of dissemination within herds. The results obtained by bacteriological culture or direct immunofluorescence (DIF) showed no significant differences, regardless the sampling device used (aspiration with Cassou pipette, metal and plastic scraper). C. fetus qPCR, on the other hand, yielded better results with an in-house DNA extraction method than with a commercial kit (75% vs 66.6%). Furthermore, qPCR diagnosis was more efficient than culture (66.6%) or DIF (56%). Bacteremia in whole blood samples was negative by qPCR and bacteriological culture in all samples. Altogether, this study demonstrated the transmission of Cff from heifers to bull and also showed that PCR-based methods are promising for the diagnosis of Bovine Genital Campylobacteriosis from clinical samples of PS.

Comparison of PCR-HRM, colorimetric LAMP and culture based diagnostic assays in the detection of endometritis caused by Streptococcus equi subsp. zooepidemicus in mares.

Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) is one of the causative agents of equine endometritis. In this study, a panel of different bacterial species, and colonies derived from bacteriological cultures of 38 clinical samples, were subjected to Loop-Mediated Isothermal Amplification (LAMP) assay and PCR, followed by high-resolution melt (HRM) curve analysis. All clinical samples were genotyped into three distinct groups based on HRM curve analysis. Differences in melting curve profiles were a reflection of DNA variation in sorD gene which was confirmed by DNA sequencing. A mathematical model based on Genetic Confidence Percentage (GCP) was used in HRM curve analysis and a cut-off point value was established which differentiated S. zooepidemicus isolates without requiring visual interpretation of curve profiles. The accuracy of PCR-HRM and bacterial culture in detection of S. zooepidemicus were identical with 100% sensitivity and specificity, while LAMP assay had similar specificity but a lower sensitivity (89.5%). PCR-HRM and LAMP assay provided an effective detection method with a turn-around time of six hours for PCR-HRM and 120min for LAMP assay, compared to a minimum three days that was required when routine bacteriological culture method was used. In summary, results indicate that LAMP had the quickest turnaround, and HRM curve analysis could potentially be used for genotyping without DNA sequencing. Any mare suspected of endometritis will benefit from developed rapid diagnostic tests for detection of S. zooepidemicus and proper treatment prior to being bred and will mitigate unnecessary treatment and antibiotic resistance.

2178. Microbiological Diagnosis of Ventilator Associated Pneumonia Caused by Gram Negative Bacterias Resistant to Carbapenems Using a Fast Molecular Method.

Abstract Background Ventilator-associated pneumonia (VAP) is one of the most important healthcare-associated infections. The burden of VAP regard morbility and mortality is significant. Most of the etiological agents of VAP are Gam negative organisms and a proportion of them could be resistant to carbapenems. GeneXpert Carba-R is a molecular test originally designed to detect rectal colonization by microorganisms expressing resistance genes to carbapenems (NDM, KPC, VIM, IMP, OXA-48). The aim of this study was to determine how useful is to use GeneXpert Carba-R in clinical samples of aspirates of bronchial secretion in patients with VAP. Methods This is a prospective observational study in a sample of patients that developed VAP at the intensive care unit in Hospital Dr. Fernando Vélez Paiz (Managua, Nicaragua) between April 2021 and December 2021. The diagnostic criterias of the CDC for VAP were used. Samples of bronchoalveolar secretions were processed using GeneXpert Carba-R and by bacteriological conventional culture. The molecular method GeneXpert Carba-R was able to detect genes as NDM, KPC, VIM, OXA-48 and IMP. The presence of any of them was considered as microorganism resistant to carbapenems and the result was correlated with the final identification and susceptibility pattern obtained in the bacteriological culture using the system Vitek2. Results A total of 45 patients were recruited in the study. Twenty-seven patients (60%) had at least one gene of resistance detected by GeneXpert Carba-R. The most frequent gene detected was NDM (81%). The cultures identified Acinetobacter baumannii (36%), Klebsiella pneumoniae (27%), and Pseudomonas aeruginosa (23%). The sensitivity and the specificity of the GeneXpert Carba-R for the diagnosis of a organism resistant to carbapenems were 86.7% (CI95%: 71.1-95-8) and 93.3% (CI95%: 80.7%-100%) respectively. The risk factors to develope a VAP with an organism expressing a gene of resistance were diabetes mellitus, extended staying in ICU, SOFA score > 2 points, mechanical ventilation ≥ 8 days, and to have had septic shock at the admission. Correlation between GeneXpert Carba-R and bacteriological culture for microbiological diagnosis of VAP caused by carbapenem-resistant bacterias. Conclusion To process GeneXpert Carba-R directly of bronchoalveolar secretions was useful in the diagnosis of VAP caused by microorganisms resistant to carbapenems. The most frequent gene detected was NDM. Disclosures All Authors: No reported disclosures.

Dissemination of antimicrobial resistance and Potassium Tellurite (PT) in the hospital environment: can the use of means with Tellurite and the detection of insertion sequences contribute to prevention and intervention?

Multidrug resistance is a public health problem. Enterobacteriaceae strains may be reservoirs of antimicrobial and potassium tellurite (PT) resistance genes, which is a determinant of bacterial escape to intraphagocytic killing mechanisms. The mobility of resistance genes and their genetic rearrangements are significantly involved in the dissemination of these genes. Mobile genetic elements such as integrons and transposons, as well as IS26 (considered among the predominant ISs), facilitate the formation and mobilization of sets of resistance genes in plasmids capable of transferring these determinants of resistance and virulence horizontally. There is evidence of associations, in plasmids, of genes encoding adhesins, toxins and antimicrobial resistance, possibly related to PT resistance. In the present work, 342 samples were collected for bacteriological culture in different units of a University Hospital in Rio de Janeiro, Brazil (Hospital Kitchen, Medical and Surgical Clinics Wards, and Intensive Care Unit): 98 samples from hands of professionals, 85 hand samples from food handlers, 104 stool samples (rectal swab) from patients and 55 food samples. We isolated 27 strains of Enterobacteriaceae through selective media containing cephalothin (32µg/mL). Bacterial identification was performed by conventional phenotypic methods. Antimicrobial susceptibility tests, as well as the phenotypic test for Extended-Spectrum Beta-lactamases (ESBLs) production, were performed by disk diffusion. PT resistance was also tested by direct seeding in media with 25µg/mL and 112 µg/mL of the compound. Plasmids were visualized by agarose gel electrophoresis of bacterial DNA extracts. Additionally, antimicrobial resistance genes and IS26 were detected by PCR assays. From a total of 27 strains of Enterobacteriaceae isolated, eight strains of Enterobacteriaceae were selected, considering phenotypes indicative of ESBLs production, resistance to aminoglycosides and presence of plasmids of high and low molecular weight (from the hands of food handlers, food and feces from hospitalized patients). Three strains 3/8 (37.5%) were resistant to aminoglycosides and cephalosporins, concomitantly. Four 4/8 strains (50.0%) were positive for the phenotypic test for ESBL production and six 6/8 strains (75.0%) were resistant to PT. Strains with resistance to aminoglycosides and producing ESBL showed amplification product for the genes tested. We consider that these antimicrobial resistance genes, also the determinants for resistance to PT (as a bacterial virulence factor), as well as IS26, may contribute to the plasticity and fitness of R plasmids, in different environments, favoring the circulation of relevant pathogenic strains.

Deep learning based CT images automatic analysis model for active/non-active pulmonary tuberculosis differential diagnosis.

Active pulmonary tuberculosis (ATB), which is more infectious and has a higher mortality rate compared with non-active pulmonary tuberculosis (non-ATB), needs to be diagnosed accurately and timely to prevent the tuberculosis from spreading and causing deaths. However, traditional differential diagnosis methods of active pulmonary tuberculosis involve bacteriological testing, sputum culturing and radiological images reading, which is time consuming and labour intensive. Therefore, an artificial intelligence model for ATB differential diagnosis would offer great assistance in clinical practice. In this study, computer tomography (CT) scans images and corresponding clinical information of 1160 ATB patients and 1131 patients with non-ATB were collected and divided into training, validation, and testing sets. A 3-dimension (3D) Nested UNet model was utilized to delineate lung field regions in the CT images, and three different pre-trained deep learning models including 3D VGG-16, 3D EfficientNet and 3D ResNet-50 were used for classification and differential diagnosis task. We also collected an external testing set with 100 ATB cases and 100 Non-ATB cases for further validation of the model. In the internal and external testing set, the 3D ResNet-50 model outperformed other models, reaching an AUC of 0.961 and 0.946, respectively. The 3D ResNet-50 model reached even higher levels of diagnostic accuracy than experienced radiologists, while the CT images reading and diagnosing speed was 10 times faster than human experts. The model was also capable of visualizing clinician interpretable lung lesion regions important for differential diagnosis, making it a powerful tool assisting ATB diagnosis. In conclusion, we developed an auxiliary tool to differentiate active and non-active pulmonary tuberculosis, which would have broad prospects in the bedside.

Intrapleural Instillation of Sodium Bicarbonate versus Urokinase in Management of Complicated Pleural Effusion: A Comparative Cohort Study.

The main target is evacuation; however, with evidence about the value of intrapleural instillation of different fibrinolytic agents still under evaluation, our aim was comparing the effectiveness and safety of intrapleural instillation of sodium bicarbonate (NaHCO3) in comparison with urokinase in patients with infected pleural effusion. Our prospective cohort study included 40 patients with complicated empyema; the diagnosis was based on analysis of aspirated fluid in association with radiological and bacteriological culture. The patients were subjected to instillation of two different fibrinolytic agents; the first one was NaHCO3, the second was urokinase. The commonest underlying chest infection that was visualized by CT was pneumonia 70%. Nearly half of cases had community-acquired infection (45%), and more than half of them (55%) had anaerobic infection, and only five cases had TB pleural effusion based on ADA-positive, tuberculin skin test in addition to Abram's needles closed biopsy. The rate of repeated therapeutic thoracentesis success in each group was 85%; 80% in NaHCO3 group, and 90% in urokinase group, both of them was significantly equal, P=0.37. Moreover, the frequency of complications in all patients was less than 13%, hence hemothorax and iatrogenic pneumothorax was 12.5%, and only 10% of cases were admitted in ICU after the maneuver, with insignificant difference in between the groups. However, looking at the smaller rate of RTT failure of NaHCO3 or urokinase, the logistic regression model showed that RTT-NaHCO3 was insignificantly related to failure in both unadjusted and adjusted models, P=0.37 and 0.32, respectively, and only smoking habits increase the likelihood of failure 9-fold (OR=8.9, P=0.04) with respect to age, sex, and treatment methods. The efficacy of repeated therapeutic thoracentesis (RTT) with intrapleural instillation of NaHCO3 was effective and safe, the same as urokinase, with consideration that NaHCO3 was much more available and affordable than urokinase.

Arthroscopic revision cuff repair: do tendons have a second chance to heal?

Few studies have investigated postoperative tendon integrity after reoperation for failed rotator cuff repair. The purpose of this study was to evaluate the anatomic and clinical outcomes of arthroscopic revision rotator cuff repair (AR-RCR) and identify the risk factors related to re-retear. Sixty-nine consecutive patients (mean age, 55 years) with primary failed open (38%) or arthroscopic (62%) cuff repairs underwent AR-RCR and were reviewed regarding clinical examination findings and imaging studies. Patients with massive cuff tears and upward humeral migration (acromiohumeral distance < 6 mm) or glenohumeral osteoarthritis were excluded. Revision repair was performed by a single, experienced shoulder surgeon. Complete footprint coverage was achieved in all cases using a single-row (70%), double-row (19%), or side-to-side (11%) technique. The primary outcome measure was tendon healing assessed with magnetic resonance imaging (57 cases) or computed tomography arthrogram (12 cases) performed at minimum 1-year follow-up. Secondary outcome measures included functional outcome scores, subjective results, and complications. The mean follow-up period was 43 months (range, 12-136 months). The cuff tendons did not heal to the tuberosity in 36% of the shoulders (25 of 69) following revision cuff surgery. Absence of tendon healing was associated with poorer shoulder function (average Constant score, 69±20 vs. 54±18; P=.003) and a decreased Subjective Shoulder Value (72% vs. 54%, P=.002). Factors that were negatively associated with tendon healing were age ≥ 55 years (odds ratio [OR], 4.5 [95% confidence interval, 1.6-12.5]; P=.02), tendon retractionof stage 2 or higher (OR, 4.4 [95% confidence interval, 1.4-14.3]; P=.01), and fatty infiltration index > 2 (OR, 10.2; P<.0001). No differences in retear rates were found between single-row and double-row cases. In 36 shoulders, tissue samples were harvested and submitted for bacteriologic culture analysis; 13 (36%) showed positive findings for infection (Cutibacterium acnesin 12 of 13) and associated antibiotic treatment was given. Overall, 25% of patients had unsatisfactory clinical results and 22% were disappointed or dissatisfied. At last follow-up, 4 patients (5.7%) underwent reoperations, with a second AR-RCR in 1 and conversion to reverse shoulder arthroplasty in 3. Despite careful patient selection and intraoperative complete footprint coverage, in this study the tendons did not heal to bone in 36% of cases after revision cuff surgery. The absence of tendon healing is associated with poorer clinical and subjective results. Patients aged ≥ 55 years and patients with larger tears (stage 2 or higher) and/or muscle fatty infiltration (fatty infiltration index > 2) have significantly lower rates of healing. Surgeons should be aware that structurally failed cuff repair may also be associated with low-grade infection.

Bacteriological and serological investigation of Clostridium perfringens in lambs

Clostridium perfringens is one of the most common and important pathogens in livestock due to its ability to produce a diverse arsenal of toxins. Owing to C. perfringens economic importance, this study aimed to determine the types and toxins of C. perfringens in newly born lambs. A total of 200 lambs of less than one-month old were examined, including 100 lambs suffered from diarrhea, 60 freshly dead and 40 apparent healthy. C. perfringens was identified morphologically and biochemically using bacteriological culture in 103 of 200 samples (51.5%). Moreover, serological typing of C. perfringens isolates revealed three serotypes, C. perfringens type A (54.2%), C. perfringens type B (28.8%) and C. perfringens type D (16.9%). The highest prevalence rate for C. perfringens infection was observed in winter (58.25%) in comparison with other seasons. The findings of the present study confirm the presence of enterotoxmia among lambs in localities under study, causing economic losses. The proper vaccination schedule particularly against C. perfringens type A and B is highly recommended.