Differentiation Of Bacterial Infection Research Articles

Rapid antigen test for adenovirus in children: Age and onset of symptoms are important

IntroductionRespiratory infection is the most common human adenovirus (HAdV) disease accounting for 7–8% of viral respiratory diseases in children less than 5 years. Differentiation of bacterial infections and viral infections is a common clinical problem. Material and methodsOne hundred oropharyngeal swabs obtained from October 2019 to November 2020 from patients attending the paediatric emergency room with suspicion of upper respiratory tract infection and negative results in influenza and RSV tests were included. Oropharyngeal swabs specimens were rapidly processed with STANDARD™ F Adeno Respi Ag FIA and the results were confirmed by RealStar® Adenovirus PCR Kit 1.0 (Altona diagnostics). ResultsSTANDARD™ F Adeno Respi Ag FIA had sensitivity and specificity values of 71.93% and 100% respectively. The performance of the test was higher in samples from children younger than 24 months and taken less than 72h since the beginning of symptoms. In this subgroup the test had 88.8% sensitivity and 100% specificity. ConclusionSTANDARD™ F Adeno Respi Ag FIA may improve the management of respiratory diseases in children younger than 24 months and less than 72h since the beginning of symptoms in paediatric emergency rooms.

Rapid antigen test for adenovirus in children: Age and onset of symptoms are important

IntroductionRespiratory infection is the most common human adenovirus (HAdV) disease accounting for 7–8% of viral respiratory diseases in children less than 5 years. Differentiation of bacterial infections and viral infections is a common clinical problem. Material and methodsOne hundred oropharyngeal swabs obtained from October 2019 to November 2020 from patients attending the paediatric emergency room with suspicion of upper respiratory tract infection and negative results in influenza and RSV tests were included. Oropharyngeal swabs specimens were rapidly processed with STANDARD™ F Adeno Respi Ag FIA and the results were confirmed by RealStar® Adenovirus PCR Kit 1.0 (Altona diagnostics). ResultsSTANDARD™ F Adeno Respi Ag FIA had sensitivity and specificity values of 71.93% and 100% respectively. The performance of the test was higher in samples from children younger than 24 months and taken less than 72h since the beginning of symptoms. In this subgroup the test had 88.8% sensitivity and 100% specificity. ConclusionSTANDARD™ F Adeno Respi Ag FIA may improve the management of respiratory diseases in children younger than 24 months and less than 72h since the beginning of symptoms in paediatric emergency rooms.

POS1367 PROCALCITONIN IN RHEUMATOLOGY

Background:The differentiation between infection and aseptic inflammation is difficult and often a challenge in the daily practice of rheumatology.Procalcitonin (PCT) is a preferred marker for bacterial infections that allows the rheumatologist to make an early diagnosis, choose an appropriate antibiotic therapy for bacterial infection, and avoid unnecessary antibiotic therapy for inflammation.Objectives:To study the levels of PCT in various inflammatory states observed in a rheumatology department, and to assess its possible discriminating role in the differentiation of bacterial infection from other inflammatory processes.Methods:This is a preliminary monocentric retrospective study conducted from January 2018 to December 2020 in our rheumatology department. The inclusion criteria were all patients hospitalized in rheumatology for a rheumatic or autoimmune disease or a bone and joint infection.PCT samples from patients were analyzed along with general signs (fever/chills) and with routine assessment (blood count including white blood cell count(WBC), erythrocyte sedimentation rate (ESR)and C reactive protein(CRP)) in patients admitted to hospitalfor a fever or a biological inflammatory syndrome, or both, with a laboratory cut-off value of 0.5 ng/ml.Results:20 patients were included. Their mean age was 46.1 (extremes 19 – 66)and the with sex ratio was 1. Three patients had a history of autoimmune disease, 2 of neoplasia, 1 with chronic terminal kidney failure and hemodialysis, and 4 patients took antibiotics before hospitalization. The mean PCT was 100.01ng/ml (extremes 0.01-200), and Sensitivity at 57.44% and specificity at 100%, PPV: 100%, NPV: 81.25%.The patients were divided according to their final diagnosis into 3 groups: bacterial or fungal infection; inflammatory abacterian disease (autoimmune or rheumatic flare, neoplasia, metabolic, reactive arthritis); infection + inflammatory abacterian disease. Group 1 included 4 patients, their mean PCT was 6.92ng/ml (0.16-26.80),mean CRP was 131.725 mg/L, and mean ESR was 50 mm, and 25% had hyperleukocytosis.2 patients had already taken antibiotics before admission. Group 2 included 13 patients, their mean PCT was 0.025 ng/mL (0.01-0.13), mean CRP was 132.25mg/L, mean ESR was 84.38mm, and 30.77% of them had hyperleukocytosis. Group 3 included 3 patients, their mean PCT was 66.88 ng/mL (0.02-200), mean CRP was 560 mg/L, mean ESR was 107.33 mm, and 33.33% had hyperleucocytosis. The patient with the highest PCT was admitted for a sepsis with uremic encephalopathy that improved after hemodialysis. A control PCT was made in 2 patients with infection who received antibiotics,showing a decrease or negativation compared to the initial value of PCT.Conclusion:Our study showed that PCT levels only increased significantly in bacterial infections. The PCT values were more discriminating than the level of WBC and CRP in differentiating a bacterial infection from another inflammatory process, hence the value of using this marker in case diagnosis doubt.Group 1(n=4)Group 2(n=13)Group 3(n=3)Mean age4546.7744.67Sex ratio M/F2/28/50/3Reason for hospitalizationPhlegmon of the left shoulder and inflammatory gonalgia in a feverish context 25%Multiple vertebral fractures 25%Acute monoarthritis of the left knee 25%Pain in the left hip with functional impairment 25%Inflammatory polyarthralgia15.38%Inflammatory back pain 23.07%Activity of his autoimmune 15.38%diseaseChronic hip pain 7.69%Acute febrile polyarthralgia 30.77%Biarthritis 7.69%Acute febrile polyarthralgia 66.67%Flare of polymyalgia rheumatica 33.33%HistoryNeoplasia 25%Autoimmune disease 23.07%End-stage chronic renal disease with hemodialysis 33.33%PCT indicationSuspected septic arthritis 75%Exploration of inflammatory syndrome 25%Suspicion of arthritis 46.15%Exploration of inflammatory syndrome 53.85%Suspicion of sepsis 33.33%Exploration of inflammatory syndrome 66.67%Mean PCT value (ng/ml)6.920.02566.88fever/chills75%30.77%33.33%Biological parametersHyperleukocytosisESR (mm)CRP (mg/L)25%50131.72530.77 %84.38132.2533.33%107.33560Disclosure of Interests:None declared

Biomarkers for diagnosing serious bacterial infections in older outpatients: a systematic review

BackgroundThe value of biomarkers for diagnosing bacterial infections in older outpatients is uncertain and limited official guidance exists for clinicians in this area. The aim of this review is to critically appraise and evaluate biomarkers for diagnosing bacterial infections in older adults (aged 65 years and above).MethodsWe searched Medline, Embase, Web of Science and the Cochrane Library, from inception to January 2018. We included studies assessing the diagnostic accuracy of blood, urinary, and salivary biomarkers in diagnosing bacterial infections in older adults. The QUADAS-2 tool was used to assess study quality.ResultsWe identified 11 eligible studies of moderate quality (11,034 participants) including 51 biomarkers at varying thresholds for diagnosing bacterial infections. An elevated Procalcitonin (≥ 0.2 ng/mL) may help diagnose bacteraemia in older adults [+ve LR range 1.50 to 2.60]. A CRP ≥ 50 mg/L only raises the probability of bacteraemia by 5%. A positive urine dipstick aids diagnosis of UTI (+ve LR range 1.23 to 54.90), and absence helps rule out UTI (−ve LR range 0.06 to 0.46). An elevated white blood cell count is unhelpful in diagnosing intra-abdominal infections (+ve LR range 0.75 to 2.62), but may aid differentiation of bacterial infection from other acute illness (+ve LR range 2.14 to 7.12).ConclusionsThe limited available evidence suggests that many diagnostic tests useful in younger patients, do not help to diagnose bacterial infections in older adults. Further evidence from high quality studies is urgently needed to guide clinical practice. Until then, symptoms and signs remain the mainstay of diagnosis in community based populations.

Serum Procalcitonin and C-Reactive Protein Level as Markers of Bacterial Infection

Background: C-reactive protein (CRP) and procalcitonin (PCT) are useful diagnostic tools used to estimate the risk of bacterial infection and the severity of the infection. The accurate diagnosis of bacterial infection is crucial to avoid unnecessary antibiotic use and to focus on the appropriate therapy. Aim of the work: this study aimed to summarize the sensitivity and specificity of both PCT and CRP and their serum levels as markers in bacterial infection Methods: scientific websites were used to search for articles such as Pubmed and Google Scholar. Several keywords were used to obtain all possible articles about the subject. Conclusion: overall accuracy of PCT markers is higher than that of CRP markers in differentiation of bacterial infections

Detection of Bacteria-Specific Metabolism Using Hyperpolarized [2-13C]Pyruvate.

The differentiation of bacterial infection from other causes of inflammation is difficult in clinical practice and is critical where patient outcomes rely heavily on early interventions. In addition to physical exam and laboratory markers, several imaging modalities are frequently employed, but these techniques generally target the host immune response, rather than the living microorganisms themselves. Here, we describe a method to detect bacteria-specific metabolism using hyperpolarized (HP) 13C magnetic resonance spectroscopy. This technology allows visualization of the real-time conversion of enriched 13C substrates to their metabolic products, identified by their distinct chemical shifts. We have identified the rapid metabolism of HP [2-13C]pyruvate to [1-13C]acetate as a metabolic signature of common bacterial pathogens. We demonstrate this conversion in representative Gram-negative and Gram-positive bacteria, namely, Escherichia coli and Staphylococcus aureus, and its absence in key mammalian cell types. Furthermore, this conversion was successfully modulated in three mutant strains, corresponding to deletions of relevant enzymes.

Procalcitonin (PCT) As A Promising Marker For Diagnosis and Differentiation of Bacterial Infections

Background: Bacteremia is a life-threatening infection whose prognosis is highly dependent on early recognition and treatment with appropriate antibiotics. Early identification of bacterial infection in patients with fever is important for prompt treatment. However, the available parameters such as C-reactive protein (CRP) and leukocyte counts are not very specific. This study was aimed to assess the diagnostic value of procalcitonin (PCT) and cholesterol for bacterial infection in febrile patients. Procalcitonin levels have been shown to distinguish between bacteremia and noninfectious inflammatory states accurately and quickly in critically ill patients. Also a decrease in plasma lipids occurs during severe sepsis and has prognostic implications in critical illness. Methods: Review of the medical records of every patient treated between May, 2014 and May, 2015 who had bacteremia caused by either Gram positive (GP) or Gram negative (GN) bacteria, and whose PCT, WBCs, CRP and cholesterol levels were measured at the onset of infection Results: 88 episodes of either GN bacteremia (n = 56) or GP bacteremia (n = 32) were included. Procalcitonin levels were found to be markedly higher in patients with GN bacteremia than in those with GP bacteremia. TLC, CRP, PCT were significantly increased, while cholesterol was significantly decreased in cases when compared to control group. Conclusion: In a critically ill patient with clinical sepsis, GN bacteremia could be associated with higher PCT values than those found in GP bacteremia, regardless of the severity of the disease. Low lipid levels, particularly low Cholesterol, pointed to bacterial infection Reflecting the severity of disease, plasma lipid levels may be a complementary tool in the diagnostic workup of patients with septicemia.

(99m)tc-Ubiquicidin [29-41], a Promising Radiopharmaceutical to Differentiate Orthopedic Implant Infections from Sterile Inflammation.

Ubiquicidin (UBI) [29-41] is a synthetic cationic antimicrobial peptide that preferentially binds to bacterial cell membrane at the site of infection. We aimed to assess diagnostic value of (99m)Tc-UBI [29-41] as a radiopharmaceutical in differentiation of bacterial infection from sterile inflammation in suspected orthopedic implants. Nine patients suspected for orthopedic implant infection, all males with the mean age of 41.6 ± 20.9 years, were studied. A dose of 10 MBq/Kg (range : 555-740 MBq) (99m)Tc-UBI [29-41] was injected intravenously. A dynamic study followed by static whole body imaging at 30, 60 and 120 min post-radiotracer injection was acquired. Periprosthetic tissue culture was considered the closest test to a gold standard for diagnosing infections and scintigraphic scans were categorized as true- or false-positive and true- or false-negative, considering the bacterial culture as the gold standard. No adverse reaction was observed during or after the radiotracer injection days. There were five true positive, four true negative and no false positive and false negative scans. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were all calculated as 100%. We found a high diagnostic accuracy for (99m)Tc-UBI [29-41] scintigraphy in differentiation of bacterial infection from sterile inflammation in suspected orthopedic implants. Therefore, (99m)Tc-UBI [29-41] scintigraphy might be potentially recommended as a safe and promising imaging modality in these settings. However, further studies on a larger number of patients and different pathologies are still needed.

Serial plasma procalcitonin levels in patients requiring admission to liver ITU with paracetamol induced acute liver failure

Introduction Patients with paracetamol-induced acute liver failure have a clinical state resembling septic shock. There is a high frequency of bacterial infection in these patients contributing to the development of multiorgan failure. In the normal liver, Kupffer cells play a major role in clearing bacteria from portal blood. The usual signs of sepsis cannot be used to differentiate between severe hepatic necrosis and bacterial infection. Procalcitonin (PCT) has been reported to be a selective inflammatory marker that rises in bacterial infection but not in non-infection related inflammation. Possible sources of PCT include monocytes and hepatocytes. We hypothesised that levels of PCT might assist in the differentiation of bacterial infection from toxic inflammatory insult. Method: Serial plasma PCT was measured daily, using a chemiluminescent immunoassay assay in 22 patients admitted with PIALF until either day 5 or discharge and levels compared with APACHE 11 scores, conventional inflammatory markers, liver function tests and microbiological cultures. Results: From a total of 22 patients 11 survived with medical support alone and 11 did not (seven died, four received liver transplants). A total of 35 blood, 15 urine, 16 sputum cultures were prepared: four endotracheal sputum cultures were positive. Eighty-one daily plasma samples were collected for PCT measurement (Table 40). Upon admission the following results were obtained: APACHE 11 (4–34) median 19; PCT (1.7–72.1) median 10.6 ng ml−1; INR (2–>15) median 3.6; AST (151–17080) median 8726 IU litre−1. PCT in non-infected patients was (0.9–123.8) median 9.4 ng ml−1. PCT on day of positive culture was (2.3–72.2) median 42.9 ng ml−1. Conclusion In patients with paracetamol-induced acute liver failure PCT is significantly higher than in normal controls and correlates with daily APACHE II score independently of the severity of liver insult, however, admission PCT does not correlate with survival. PCT did not specifically rise in those patients who developed chest infection and therefore does not appear to be a useful marker of bacterial infection in this group of patients.

Antimicrobial Chemotherapy for Children with Malignancy

AbstractInfection is the major complication occurring in children with cancer and is often fatal.Since the clinical manifestations of infection are slight, except for fever, a definitive diagnosis is difficult in the early phase of infection, but using laboratory parameters, the differentiation of bacterial infections may be possible to some extent. The infection cannot be treated only by antimicrobial chemotherapy, but supportive measures such as neutrophil transfusion, and other biological medications should be given in consideration of the deficiency of the immune defense mechanisms of the patient. Anticancer treatment is also needed, along with antimicrobial treatment.The prophylactic use of antimicrobial drugs is still controversial but it is effective, depending on the type of infection for which it is used, and on the status of the defective defense mechanism in the patient who is on cancer chemotherapy.

NBT test in the diagnosis of febrile patients.

Leukocytosis frequently accompanies bacterial infection, but stresses incident to burns, diabetic ketoacidosis, seizures, emotional disturbances and strenuous exercise may also produce leukocytosis and limit its usefulness in differential diagnosis. A major step in differentiation of bacterial infection from nonbacterial diseases accompanied by leukocytosis and fever was made by Park and his associates1 with the use of nitroblue tetrazolium (NBT) dye. They demonstrated that the percentage and absolute number of polymorphonuclear leukocytes that reduced NBT dye to blue-black formazan deposits was strikingly increased in bacterial infection as compared to normal persons or patients with nonbacterial illnesses.The original observations of Park . . .