Clinical Diagnosis Of Infection Research Articles

Clinical and Histopathological Evolution of Acute Intraperitoneal Infection by Streptococcus agalactiae Serotypes Ib and III in Nile Tilapia

Streptococcus agalactiae is a highly invasive bacterium that causes significant economic losses in tilapia aquaculture around the world. Furthermore, it is a pathogen for mammals, including humans, emphasizing its importance in One Health. The aim of this work was to evaluate the evolution of clinical and histopathological lesions caused by acute infection with two serotypes of S. agalactiae. For this, two strains isolated from natural outbreaks in Brazilian aquaculture farms (S13, serotype Ib; S73, serotype III) were used to challenge juvenile Nile tilapia (Oreochromis niloticus) intraperitoneally. Target organ samples were collected ten times, between 1 and 96 h post-infection, for microbiological and histopathological analyses. Anorexia was the first clinical sign and the first death occurred at 24 and 30 h in the fish infected with strains S13 and S73, respectively. Serotype Ib initially caused more pronounced lesions in the nervous system; however, serotype III lesions progressed more aggressively, reaching the same severity as those of serotype Ib. This trend was repeated in the mortality curve after 32 h. These results elucidated the important stages in the pathogenesis of S. agalactiae serotypes Ib and III in tilapia and suggest “tips and tricks” to improve the positive culture rate in the clinical diagnosis of infections in some tissues.

Imaging features of soft-tissue infections.

Skin and soft tissues are among the most common sites of infections. Infections can involve the superficial epidermis to deep muscles and bones. Most infections spread through contiguous structures, although hematogenous spread can occur in the setting of an immunocompromised state and with atypical infections. While clinical diagnosis of infections is possible, it often lacks specificity, necessitating the use of imaging for confirmation. Cross-sectional imaging with US, CT, and MRI is frequently performed not just for diagnosis, but to delineate the extent of infection and to aid in management. Nonetheless, the imaging features have considerable overlap, and as such, it is essential to integrate imaging features with clinical features for managing soft tissue infections. Radiologists must be aware of the imaging features of different infections and their mimics, as well as the pros and cons of each imaging technique to properly use them for appropriate clinical situations. In this review, we summarize the most recent evidence-based features of key soft tissue infections.

Molecular rapid diagnostic testing for bloodstream infections: Nanopore targeted sequencing with pathogen-specific primers

Nanopore sequencing, known for real-time analysis, shows promise for rapid clinical infection diagnosis but lacks effective assays for bloodstream infections (BSIs). We prospectively assessed the performance of a novel nanopore targeted sequencing (NTS) assay in identifying pathogens and predicting antibiotic resistance in BSIs, analyzing 387 blood samples from December 2021 to April 2023. The positivity rate for NTS (69.5%, 269/387) nearly matches that of metagenomic next-generation sequencing (mNGS) (74.7%, 289/387; p=0.128) and surpasses the positivity rate of conventional blood culture (BC) (33.9%, 131/387; p<0.01). Frequent pathogens detected by NTS included Klebsiella pneumoniae (n=54), Pseudomonas aeruginosa (n=36), Escherichia coli (n=36), Enterococcus faecium(n=30), Acinetobacter baumannii(n=26), Staphylococcus aureus(n=23), and Human cytomegalovirus (n=37). Against a composite BSI diagnostic standard, NTS demonstrated a sensitivity and specificity of 84.0% (95% CI 79.5%-87.7%) and 90.1% (95% CI 81.7%-88.5%), respectively. The concordance between NTS and mNGS results (the percentage of total cases where both either detected BSI-related pathogens or were both negative) was 90.2% (359/387), whereas the consistency between NTS and BC was only 60.2% (233/387). In 80.6% (50/62) of the samples with identical pathogens identified by both NTS tests and BCs, the genotypic resistance identified by NTS correlated with culture-confirmed phenotypic resistance. Using NTS, 95% of samples can be tested and analyzed in approximately 7h, allowing for early patient diagnosis. NTS is rapid, sensitive, and efficient for detecting BSIs and drug-resistant genes, making it a potential preferred diagnostic tool for early infection identification in critically ill patients.

Clinical Analysis of Metagenomic Sequencing of Plasma Microbial Cell-Free DNA for Infected Patients in SAA

Backgroun d: As a high-risk group of clinical infection, patients with severe aplastic anemia (SAA) have high mortality due to agranulocytosis or immune function impairment. The current conventional detection methods such as blood culturetissue chulture etc. often cannot identify pathogenic bacteria. We evaluate the diagnostic performance of metagenomic next-generation sequencing (mNGS), and explore the application value of mNGS in infected patients in SAA, in order to provide help for precision therapy. Methods: From Ocb 2020 to Dec 2022 in our center, we enrolled 70 SAA patients with infection and investigated the usefulness of mNGS of plamsa or tissue DNA for identification of infectious pathogens. The consistency of the results of mNGS and the results of routine etiological detection (blood culture(BC), swab/tissue culture) with clinical infection diagnosis and the influence of the results of mNGS on clinical infection treatment were compared. Results: 70 SAA patients of mNGS were detected, including plasma-mNGS 66 cases and tissue-mNGS 4 cases. Among all patients, 48 cases(68.6%) were positive. In comparison to blood culture, the positive and negative agreement of mNGS were 100% (13/13) and 38.6% (22/57), respectively. In 48 mNGS positive cases, 36 patients (75%) underwent antimicrobials adjustment, resulting in positive impact on 30 patients. Fungi were detected in 29 cases, the detection rate was 41.4% (29/70) by mNGS, otherwise 2.8% (2/70) by BC. Of the 70 patients with SAA, 55 infections eventually impproved (78.6%). Conclusion: The positive rate of mNGS detection and the consistent rate with clinical diagnosis are higher than that of conventional etiological detection, which provides a faster and more sensitive detection method for infected patients in SAA. 【 Key words 】 Metagenomic Sequencing ; Plasma Microbial Cell-free DNA; Aplastic anemia; Infection; pathogen diagnosis

A study of clinical utility of peri operative c- reactive protein testing in general surgery at tertiary care centre

Background and objectives Clinical diagnosis of infections, inflammatory diseases, and response monitoring can be done by C reactive protein (CRP), an acute-phase protein. CRP measurement in the perioperative period was studied, and patterns of change were analyzed, for elective general surgical patients. Study aimed to test the efficacy of C - reactive protein as a predictor for surgical stress and diagnostic accuracy to detect early postoperative infectious complications. Objective of this study was to estimate perioperative serum C - reactive protein level in patients undergoing elective surgeries. 1. To find out the relation between serum C-reactive protein level and severity of surgical stress. 2.To find out diagnostic accuracy of C-reactive protein to detect early postoperative infectious complications.

MICROBIOLOGICAL ASPECT OF STAPHYLOCOCCAL INFECTION IN SEVERE DEGREE OF BURNS

Introduction: Burns serve as one of the most common devastating forms of trauma. Significant thermal injuries induce skin disruption and immunosupression that predispose patients to infectious complication. The importance of sampling, detection, and proper treatment for wound infections will significantly increase the likelihood of clinical improvement of the patients. Case: A 44-years-old male came to hospital due to electrical shock. There were serious burns to his face, chest, arms, and legs, some of which were second- and third-degree burns. The patient was conscious, without problems on airway and breathing. Leukocytosis with neutrophilia was presented from laboratory examination, with an increase in liver enzymes and serum creatinine. The gram-positive cocci with leucocytes were revealed from gram examination, and colonization of Staphylococcus aureus was found. Intravenous cefazolin was administered according to the sensitivity test. Discussion: Infection causes the increase in morbidity and mortality of burn patients. Clinical diagnosis of infection must be supported microbiologically by gram examination and culture. One of the most common infectious agents in severe burns is Staphylococcus aureus. The significance of S.aureus as the leading cause of infection must be supported by microbiological data. Dominant growth in culture media and induction of host inflammatory response were indicated as significance of infection. Conclusion: Clinical and microbiological diagnosis of burns infection play important role to prevent complications in severe degree of burns.

Effect of Jiedu Limai decoction in septic patients with syndrome of heat-toxin exuberance

To investigate the clinical effect of Jiedu Limai decoction in septic patients with syndrome of heat-toxin exuberance. A prospective randomized controlled trial was conducted. From March 2019 to April 2020, septic patients with syndrome of heat-toxin exuberance admitted to intensive care unit (ICU) of Shanghai General Hospital and Songjiang Branch of Shanghai General Hospital were enrolled as the research objects, and they were divided into routine treatment group and Jiedu Limai decoction group by the random number table method. Patients in both groups were given standard treatment in accordance with the guidelines, and patients in the Jiedu Limai decoction group were given Jiedu Limai decoction in addition to the standard treatment, once a day for 14 days. The 28-day survival of patients of the two groups were recorded, the acute physiology and chronic health evaluation II (APACHE II) score, sequential organ failure assessment (SOFA) score, coagulation indexes, infection indexes, inflammatory cytokines and organ function indicators before treatment and 7 days after treatment in both groups were recorded, and the prognosis of the two groups were recorded. A total of 259 patients with infection or clinical diagnosis of infection admitted during the experimental observation period were included, and those who did not meet the Sepsis-3 diagnostic criteria, more than 80 years old or less than 18 years old, with multiple tumor metastases, autoimmune system diseases, with length of ICU stay less than 24 hours, with acute active gastrointestinal bleeding and with incomplete data were excluded. One hundred patients were finally enrolled, with 50 patients in the routine treatment group and 50 patients in the Jiedu Limai decoction group. There were no statistically significant differences in coagulation indexes, infection indicators, inflammatory cytokines and organ function indicators before treatment between the two groups. After 7 days of treatment, the coagulation indexes, infection biomarkers and inflammatory cytokines in the Jiedu Limai decoction group were significantly lower than those in the routine treatment group [D-dimer (mg/L): 2.2 (1.8, 8.5) vs. 4.0 (1.5, 8.7), fibrinogen (Fib, g/L): 3.7 (3.4, 4.3) vs. 4.2 (3.7, 4.3), fibrinogen degradation product (FDP, mg/L): 7.2 (5.4, 10.2) vs. 13.2 (9.2, 15.2), procalcitonin (PCT, μg/L): 0.4 (0.2, 2.9) vs. 0.5 (0.2, 0.9), C-reactive protein (CRP, mg/L): 50.1 (9.5, 116.0) vs. 75.1 (23.5, 115.2), interleukin-6 (IL-6, ng/L): 31.6 (21.6, 81.0) vs. 44.1 (14.0, 71.3), all P < 0.05], and the levels of B-type brain natriuretic peptide (BNP) and kidney injury molecule-1 (KIM-1) were significantly lowered [BNP (ng/L): 261.1 (87.5, 360.3) vs. 347.3 (128.8, 439.4), KIM-1 (μg/L): 0.86 (0.01, 1.40) vs. 1.24 (1.05, 1.57), both P < 0.05]. Compared with the routine treatment group, the number of new organ failure in the Jiedu Limai decoction group was decreased (30.0% vs. 50.0%, P < 0.05). Although there was no significant difference in 28-day mortality between the two groups (P > 0.05), the 28-day mortality in the Jiedu Limai decoction group was lower than that in the routine treatment group (18.0% vs. 24.0%). Combining Jiedu Limai decoction to the sepsis guideline in treating syndrome of heat-toxin exuberance can effectively improve patients' coagulation function, the situation of heart and renal injury, reduce the level of inflammatory cytokines, and fewer people develop new organ failure after treatment.

A non-contact device for fast screening of wound infections.

Screening for wound infection relies on the expertise of the provider. Clinical diagnosis of infections based on wound swab/biopsy results often takes a few days and may not assess the full wound. There is a need for a non-invasive tool that can quickly and accurately diagnose wound infection. Leukocyte esterase strips are used to identify various infectious diseases. However, it is not clear whether infected wounds also have elevated leukocyte esterase activities as compared with non-infected wounds. To achieve the objective, a device was developed to detect elevated leukocyte esterase activities in wounds by measuring wound exudates adsorbed onto wound dressings in 3minutes. The efficacy of the device in assessing leukocyte esterase activities across various chronic wounds was tested. Such measurements were unaffected by the type of underlying wound dressing. By correlating the device outputs with clinical adjudication of infection, we found that this device had high positive predictive values for diagnosing wound infection in a wide variety of chronic wounds. In addition, a positive device output increases the probability of detecting infected wounds, while the negative device output reduces the probability of detecting infected wounds. This rapid non-contact and disposable diagnostic tool may serve as a rapid and accurate indication of infection in the chronic wound.

Serum procalcitonin as a biomarker for differentiating between infectious and non-infectious fever after pancreas transplantation.

Laboratory biomarkers that can differentiate non-infectious fever from infectious fever after pancreas transplantation have yet to be discovered. Non-infectious fever was defined as the presence of fever (>38.3°C) in the absence of a documented clinical diagnosis of infection or a positive culture. Among 184 consecutive recipients, a total of 91 recipients developed fever within 1-month post-transplant, of whom 46 had infectious fever and 45 had non-infectious fever at our center between August 2014 and July 2019. The onset of fever was earlier in the non-infectious fever group (14.4±3.7 post-transplant days) compared with the infectious fever group (16.5±5.8 post-transplant days; p=.033). Multivariate analysis showed that serum procalcitonin at the peak of fever could significantly differentiate infectious fever from non-infectious fever (OR 53.378, 95% CI: 6.819-417.802, p<.001). The area under the curve for differentiating between the two groups was 0.853 (95% CI, 0.780-0.926) for procalcitonin and 0.667 (95% CI, 0.549-0.785) for CRP. The best cutoff values of serum procalcitonin and CRP were 0.405ng/ml (sensitivity, 77.1%; specificity, 80.8%) and 7.355mg/dl (sensitivity, 66.7%; specificity, 67.3%), respectively. Serum procalcitonin may be useful for differentiating non-infectious fever from infectious fever after pancreas transplantation.

Investigation and analysis of questionnaire on clinical thinking in the diagnosis of severe infection in Guangxi

To understand the clinical thinking of clinical staff in the diagnosis of severe infection and evaluate their ability to recognize severe infection in the early stage. A questionnaire survey was conducted to investigate the clinical thinking of clinical staff attending the academic annual meeting of critical care physicians of Guangxi Medical Doctors Association from September 26 to September 28, 2019. The objects of investigation included doctors, nurses, clinical pharmacists and medical graduate students, except for non-clinical personnel. The basis factors of clinical diagnosis of infection included clinical symptoms, specific biochemical examination, microorganism examination and Next-generation sequencing technology (NGS). The credibility level of each indicator was summarized as high (credibility of 51%-100%) and low (credibility of 0%-50%). Among the more than 600 participants, 540 people participated in the questionnaire survey (participation rate of about 90.0%), and 466 qualified questionnaires (effective rate of 86.3%) were collected, including 280 from doctors, 155 from clinical nurses, 10 from clinical pharmacists and 21 from clinical graduate students. The working years of doctors, nurses, clinical pharmacists and medical graduate students were (8.2±6.0), (6.4±6.3), (4.5±4.0) and (3.8±2.6) years, respectively. The intermediate title (43.2%) dominated in the doctors group, while junior title dominated in the nurses group, clinical pharmacists group and medical postgraduate group (53.5%, 80.0% and 81.0% respectively). Doctors and nurses were mainly from the general intensive care unit (ICU; 73.2% and 51.0% respectively). According to the results of investigation of clinical thinking on the diagnosis of severe infection, there was similar degree of recognition and credibility for infection-related symptoms in the four groups of doctors, nurses, clinical pharmacists and medical graduate students (the credibility of fever was 80.0%-91.1%, low blood pressure 76.2%-90.0%, disturbance of consciousness 80.0%-85.0%, breathing 81.0%-100.0%, reduced of urine 81.9%-90.0%). The interpretation for pathogen culture and NGS results was insufficient because 29.3%-42.6% of the medical staff did not understand NGS. There were differences in the interpretation of the results of pathogen culture (positive specimen culture could diagnose infection; medical vs. nursing vs. pharmacists vs. student: 93.6% vs. 85.2% vs. 90.0% vs. 85.7%, P = 0.021). There were significant differences among the four groups in some traditional infection-related laboratory indexes which included increased white blood cell count (WBC; χ2 = 8.542, P = 0.026), increased C-reactive protein (CRP; χ2 = 8.826, P = 0.024), increased interleukin-6 (IL-6; χ2 = 13.944, P = 0.002), positive 1, 3-β-D glucan detection test (G test; χ2 = 10.988, P = 0.009) and positive galactomannan antigen detection test (GM test; χ2 = 12.306, P = 0.004). There is difference in clinical thinking of diagnosis of severe infection among clinical medical staff in different positions, and the comprehensive diagnostic ability needs to be improved.

Infection in older adults: a qualitative study of patient experience.

Infection is common in older adults. Serious infection has a high mortality rate and is associated with unplanned hospital admissions. Little is known about the factors that prompt older patients to seek medical advice when they may have an infection. To explore the symptoms of infection from the perspective of older adults, and when and why older patients seek healthcare advice for a possible infection. A qualitative interview study among adults aged ≥70 years with a clinical diagnosis of infection recruited from ambulatory care units in Oxford, UK. Interviews were semi-structured and based on a flexible topic guide. Participants were given the option to be interviewed with their carer. Thematic analysis was facilitated using NVivo (version 11). A total of 28 participants (22 patients and six carers) took part. Patients (aged 70-92 years) had experienced a range of different infections. Several early non-specific symptoms were described (fever, feeling unwell, lethargy, vomiting, pain, and confusion/delirium). Internally minimising symptoms was common and participants with historical experience of infection tended to be better able to interpret their symptoms. Factors influencing seeking healthcare advice included prompts from family, specific or intolerable symptoms, symptom duration, and being unable to manage with self-care. For some, not wanting to be a burden affected their desire to seek help. Tailored advice to older adults highlighting early symptoms of infection may be beneficial. Knowing whether patients have had previous experience of infection may help healthcare professionals in assessing older patients with possible infection.

Postoperative Infections in Dermatologic Surgery: The Role of Wound Cultures.

Dermatologic surgery is associated with low postoperative infection rates, averaging from approximately 1% to 4.25%. Often, postoperative infections are treated empirically based on clinical diagnosis of infection, given it can take 48 to 72 hours for a wound culture to identify a pathogen. We aimed to evaluate the efficacy of empiric antibiotics in dermatologic surgery postoperative infections and if wound cultures change postoperative antibiotic therapy. A 7-center, retrospective analysis of postoperative infections, with culture data, in dermatologic surgery patients was performed. Of 91 cases of clinically diagnosed postoperative infection, 82.4% (n = 75) were successfully treated with empiric oral antibiotics (95% confidence interval [0.73-0.89], p < .0001). In 16 (17.6%) cases, initial empiric antibiotics were unsuccessful, and wound culture results altered antibiotic therapy in 9 cases (9.9%) with 6 (6.6%) of these cases requiring additional coverage for methicillin-resistant Staphylococcus aureus (MRSA). Empiric antibiotic treatment is usually appropriate for patients with postoperative surgical-site infections with wound cultures altering antibiotic management in a minority of cases. When empiric antibiotics fail, lack of MRSA coverage is usually the cause; therefore, providers should be aware of local MRSA prevalence and susceptibilities.

Clinical Diagnosis of Infection in Surgical Intensive Care Unit: You're Not as Good as You Think!

Background: Because of the everincreasing costs and the complexity of institutional medical reimbursement policies, the necessity for extensive laboratory work-up of potentially infected patients has come into question. We hypothesized that intensivists are able to differentiate between infected and non-infected patients clinically, without the need to pan-culture, and are able to identify the location of the infection clinically in order to administer timely and appropriate treatment. Methods: Data collected prospectively on critically ill patients suspected of having an infection in the surgical intensive care unit (SICU) was obtained over a six-month period in a single tertiary academic medical center. Objective evidence of infection derived from laboratory or imaging data was compared with the subjective answers of the three most senior physicians' clinical diagnoses. Results: Thirty-nine critically ill surgical patients received 52 work-ups for suspected infections on the basis of signs and symptoms (e.g., fever, altered mental status). Thirty patients were found to be infected. Clinical diagnosis differentiated infected and non-infected patients with only 61.5% accuracy (sensitivity 60.3%; specificity 64.4%; p = 0.0049). Concordance between physicians was poor (κ = 0.33). Providers were able to predict the infectious source correctly only 60% of the time. Utilization of culture/objective data and SICU antibiotic protocols led to overall 78% appropriate initiation of antibiotics compared with 48% when treatment was based on clinical evaluation alone. Conclusion: Clinical diagnosis of infection is difficult, inaccurate, and unreliable in the absence of culture and sensitivity data. Infection suspected on the basis of signs and symptoms should be confirmed via objective and thorough work-up.

Arbovirus et greffes

Arboviruses are pathogens transmitted by the bite of a hematophagous insect or mite, which emerge or re-emerge both in the tropics, where large-scale epidemics have recently occurred, and in temperate climate, with now regular description of autochthonous transmission cases. Perfectly symbolized by chikungunya, dengue, Zika or West Nile viruses, arboviruses are a problem of new magnitude in transplantation that must now be taken into consideration because the risks to the transplant recipient are real and numerous.These viruses can be transmitted by the organs, cells and tissues taken at the time of the viremic phase in the infected donor.Transplant recipients living or traveling in arbovirus circulation areas are also exposed to classical vector transmission.The early virological and clinical diagnosis of infection is then the prerequisite for rapid and appropriate medical management in order to preserve the prognosis of the patient and the graft. It requires to know the characteristics of the infection in the transplanted patient whose immunity, especially cellular, is voluntarily diminished.The absence of specific antiviral treatment finally requires the establishment of measures to prevent transmission, the only effective means of fighting against infection.

Exploring Chronic Lung Transplant (LTx) Allograft Dysfunction (CLAD): The Potential Clinical Prognostic Relevance of Single Bite Transbronchial Biopsy (TBB) Microarray

Purpose TBB histologic assessment of CLAD status, particularly late post-LTx, is typically clinically unhelpful. Microarray analyses using the Molecular Microscope Diagnostic System (MMDx) in kidney & heart recipients are proving useful in providing mechanistic targets that inform therapeutic interventions, and could show similar promise in LTx. Methods LTx recipients with clinical instability- typically a falling FEV1 and symptoms- had bronchoscopic lavage with microbiologic & cytologic analyses and TBB [4-6 bites analyzed via histology, I TBB bite by MMDx microarray (Alberta Transplant Applied Genomic Center, Edmonton)]. The MMDx uses weighted equations to reflect probabilities of 4 idealized archetypes [Normal, T-cell rejection (TCMR), antibody-mediated rejection (ABMR), Injury]. One month post-TBB a clinical diagnosis was determined, & subsequent change in FEV1 was reassessed 6 months post-TBB. Clinicians were blinded to MMDx scores. Results 48 of 50 LTx who underwent TBB assessment at 1463±1296d post-LTx, (FEV1 32-118% predicted), had an assessable TBB for MMDx. Clinical diagnoses at 1 month post-TBB were CLAD n=21, infection n=17, ABMR n=5, TCMR n=4 & effusion n=1. TBB ISHLT grade was A0 n=46, A1 n=1, B0 n=11, B1 n=1; all others Ax and/or Bx. At 6 months post-TBB, using the highest of the 4 MMDx archetype scores, 1/12 (8%) Normal, 7/14 (50%) TCMR, 5/19 (26%) ABMR & 0/3 (0%) Injury recipients, had rapidly progressive CLAD. 15 patients had DSA>500, 9/15 were in ABMR group- 4 with rapidly progressive CLAD. In 31 patients without a clinical diagnosis of infection at 1 month, 11% Normal, 58% TCMR, 60% ABMR & 0% Injury group recipients went on to have rapidly progressive CLAD. Longer term follow-up (mean of 450±168d) in the TCMR arm and ABMR arm noted there were n=4 & 3 and n=2 & 1 deaths/re-LTx respectively, with 1 other re-LTx in the Normal group: all were CLAD related. Conclusion The MMDx score on single bite TBB specimens provided potentially useful mechanistic, therapeutic & prognostic detail in LTx recipients with clinical instability, whilst TBB histology was not clinically helpful in this cohort. The apparent association or confounding of infection, DSA and a predominant ABMR phenotype is notable. A prospective trial of MMDx directed therapy may be indicated.

A novel monoclonal antibodies-based sandwich ELISA for detection of serotype 4 fowl adenovirus

ABSTRACTAs a major causative agent for hepatitis-hydropericardium syndrome (HPS) in chickens, serotype 4 fowl adenovirus (FAdV-4) has caused huge economic losses in the poultry industry globally. However, there is no commercial diagnostic test for FAdV-4 antigens. To generate a rapid approach for specific detection of FAdV-4, a monoclonal antibodies (mAbs)-based sandwich ELISA was developed. In this ELISA, a purified mAb 4A3 and a HRP-labelled mAb 3C2 specific to the fiber-2 of FAdV-4 were used as the capture antibody and detection antibody respectively. Specificity assay revealed the ELISA only reacted with FAdV-4, not with other avian viruses tested. Sensitivity assay showed the limit of detection of the ELISA was 1000 TCID50/ml and 12.5 ng/ml for the FAdV-4 and the purified GST-Fiber2 protein respectively. Moreover, the ELISA could be efficiently applied in detecting the FAdV-4 in tissue samples from a clinically-diseased chicken flock. All these data demonstrated that the ELISA developed here provides a promising tool for rapid and efficient diagnosis of clinical infection with FAdV-4.

Time-resolved fluorescent immunoassay-based combined detection of procalcitonin, C-reactive protein, heparin binding protein, and serum amyloid A1 to improve the diagnostic accuracy of early infection.

Serological tests are indispensable in the diagnosis of early infection. At present, only procalcitonin (PCT) and C-reactive protein (CRP) are commonly used in clinical practice. Recently, serum amyloid A1 (SAA1) and heparin binding protein (HBP) have been shown to be new biomarkers, because SAA1 is highly sensitive and specific for viral infections, and HBP is predictive for septic shock. In this study, PCT, CRP, HBP, and SAA1 were detected in different combinations to improve the diagnostic accuracy of early infection using the biotin-avidin amplifying system-based time-resolved fluorescent immunoassay (BA-TRFIA). A time-resolved fluorescent immunoassay for PCT, CRP, HBP, and SAA1 was developed and then tested in a clinical setting. All experiments were carried out using the DR6608 time-resolved fluorescent immunoassay analyzer. The cutoff values of PCT, CRP, HBP, and SAA1 were 0.05μg/L, 5.59mg/L, 3.83μg/L, and 1.56mg/L, respectively. The area under the ROC curve (AUC) showed that PCT˃SAA1˃CRP˃HBP>0.8. A methodological comparison of the results showed that a combination of the four biomarkers had the highest accuracy for the diagnosis of infectious diseases. The time-resolved fluorescent immunoassay-based combined detection of PCT, CRP, HBP, and SAA1 was shown to significantly improve the diagnostic accuracy of early infection. Thus, our results indicate that combined detection based on BA-TRFIA may represent a promising strategy in the clinical diagnosis of infection.

11C]Para-Aminobenzoic Acid: A Positron Emission Tomography Tracer Targeting Bacteria-Specific Metabolism.

Imaging studies are frequently used to support the clinical diagnosis of infection. These techniques include computed tomography (CT) and magnetic resonance imaging (MRI) for structural information and single photon emission computed tomography (SPECT) or positron emission tomography (PET) for metabolic data. However, frequently, there is significant overlap in the imaging appearance of infectious and noninfectious entities using these tools. To address this concern, recent approaches have targeted bacteria-specific metabolic pathways. For example, radiolabeled sugars derived from sorbitol and maltose have been investigated as PET radiotracers, since these are efficiently incorporated into bacteria but are poor substrates for mammalian cells. We have previously shown that para-aminobenzoic acid (PABA) is an excellent candidate for development as a bacteria-specific imaging tracer as it is rapidly accumulated by a wide range of pathogenic bacteria, including metabolically quiescent bacteria and clinical strains, but not by mammalian cells. Therefore, in this study, we developed an efficient radiosynthesis for [11C]PABA, investigated its accumulation into Escherichia coli and Staphylococcus aureus laboratory strains in vitro, and showed that it can distinguish between infection and sterile inflammation in a murine model of acute bacterial infection.

The Role of Infections in Preterm Labour and It’s Control: A Review

Preterm labour (PTL) is described as the premature contraction of the uterus before 37 weeks of the gestation cycle, which could results in preterm premature rupture of the membranes (PPROM) and in most cases may lead to preterm birth. Preterm labour that results in preterm birth is a leading precursor of neonatal morbidity and mortality. Infection in the uterus occurs by the aptness of pathogenic microbes to ascend from the female genital area to the uterus. Lactobacilli species constitute about 95% of the female genital normal flora. But the invasion and colonisation of the genital area by gram-negative anaerobes has endangered the female genital area and exposed it to infection. Pathogens such as Neisseria gonorrhoeae, Candida albican, adenovirus and many more are indicated to play a role in preterm labour.The symptoms and clinical diagnosis of infections in the female genital area include itching and inflammation of the vaginal area, heavy, copious yellow-grey, fishy smell discharge etc. Routine clinical investigations from the first trimester of gestation cycle and the administration of probiotics, antibiotics as well as proper toiletry hygiene have contributed to reducing the prevalence of preterm labour.&#x0D;

Assessment of Domestic Goats as Models for Experimental and Natural Infection with the North American Isolate of Rickettsia slovaca.

Rickettsia slovaca is a tick-borne human pathogen that is associated with scalp eschars and neck lymphadenopathy known as tick-borne lymphadenopathy (TIBOLA) or Dermacentor-borne necrosis erythema and lymphadenopathy (DEBONEL). Originally, R. slovaca was described in Eastern Europe, but since recognition of its pathogenicity, human cases have been reported throughout Europe. European vertebrate reservoirs of R. slovaca remain unknown, but feral swine and domestic goats have been found infected or seropositive for this pathogen. Recently, a rickettsial pathogen identical to R. slovaca was identified in, and isolated from, the American dog tick, Dermacentor variabilis. In previous experimental studies, this organism was found infectious to guinea pigs and transovarially transmissible in ticks. In this study, domestic goats (Capra hircus) were experimentally inoculated with the North American isolate of this R. slovaca-like agent to assess their reservoir competence–the ability to acquire the pathogens and maintain transmission between infected and uninfected ticks. Goats were susceptible to infection as demonstrated by detection of the pathogen in skin biopsies and multiple internal tissues, but the only clinical sign of illness was transient fever noted in three out of four goats, and reactive lymphoid hyperplasia. On average, less than 5% of uninfected ticks acquired the pathogen while feeding upon infected goats. Although domestic goats are susceptible to the newly described North American isolate of R. slovaca, they are likely to play a minor role in the natural transmission cycle of this pathogen. Our results suggest that goats do not propagate the North American isolate of R. slovaca in peridomestic environments and clinical diagnosis of infection could be difficult due to the brevity and mildness of clinical signs. Further research is needed to elucidate the natural transmission cycle of R. slovaca both in Europe and North America, as well as to identify a more suitable laboratory model.