Early predictors of bacterial pneumonia infection in children with congenital heart disease after cardiopulmonary bypass: a single-centre retrospective study.

OBJECTIVES: The objective of this study was to evaluate the early predictors of bacterial pneumonia infection in children with congenital heart disease (CHD) after cardiopulmonary bypass (CPB). DESIGN: Retrospective study. SETTING: A freestanding tertiary paediatric hospital in China. PARTICIPANTS: Patients admitted to the hospital due to CHD who underwent open-heart surgery. OUTCOME MEASURES: We retrospectively reviewed and analysed data from 1622 patients with CHD after CPB from June 2018 to December 2020 at the Children's Hospital of Nanjing Medical University. Enrolled patients were assigned to an infection group or a non-infection group according to the presence of postoperative bacterial pneumonia infection, and the differences in clinical indicators were compared. Potential predictors were analysed by multivariate logistic regression analysis and area under the curve (AUC) analysis. RESULTS: Among the 376 patients (23.2%) in the infection group, the three most common bacteria were Streptococcus pneumoniae in 67 patients (17.8%), Escherichia coli in 63 patients (16.8%) and Haemophilus influenzae in 53 patients (14.1%). The infection group exhibited a lower weight (8.0 (6.0-11.5) kg vs 11.0 (7.5-14.5) kg, p<0.001). In the infection group, procalcitonin (PCT) (ng/mL: 4.72 (1.38-9.52) vs 1.28 (0.47-3.74), p<0.001) and C reactive protein (CRP) (mg/L: 21.0 (12.1-32.0) vs 17.0 (10.0-27.0), p<0.001) levels were significantly greater than those in the non-infection group. Binary logistic regression analysis revealed that weight, PCT and CRP were independent risk factors for pulmonary bacterial infection after CPB. The AUCs of weight, PCT, CRP and PCT+CRP for predicting pulmonary bacterial infection after CPB were 0.632 (95% CI 0.600 to 0.664), 0.697 (95% CI 0.667 to 0.727), 0.586 (95% CI 0.554 to 0.618) and 0.694 (95% CI 0.664 to 0.724), respectively, and the cut-off values were ≤10.25 kg, ≥4.25 ng/mL, ≥6.50 mg/L and ≥0.20, respectively. The sensitivities were 69.7%, 54.0%, 93.9% and 70.2%, and the specificities were 53.5%, 77.7%, 19.4% and 59.1%, respectively. CONCLUSIONS: In our study, weight, PCT and CRP were found to be independent predictors of pulmonary bacterial infection after CPB. Moreover, PCT was the most specific predictor, and CRP was the most sensitive independent predictor that might be beneficial for the early diagnosis of pulmonary bacterial infection after CPB in patients with CHD.

Plasma levels of neurogenic inflammation related neuropeptides in pediatric patients with community-acquired pneumonia and their potential diagnostic value in distinguishing viral and bacterial pneumonia.

Neurogenic inflammation is involved in the development and progression of respiratory inflammatory diseases. However, its role in community-acquired pneumonia (CAP) remains unclear. We therefore aimed to investigate plasma levels of neurogenic inflammation-related neuropeptides, calcitonin gene-related peptide (CGRP), substance P (SP), vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY), and procalcitonin (PCT) in pediatric patients with CAP and to assess their diagnostic value in viral and bacterial/mixed pneumonia. A total of 124 pediatric patients with CAP (1 month-18 years old) and 56 healthy children of similar ages were prospectively enrolled. The patients were classified as viral (n = 99) and bacterial/mixed (n = 25) pneumonia. Plasma levels of the peptides were quantified by ELISA. ROC analysis was performed to evaluate possible diagnostic value of the peptides. While plasma levels of CGRP, VIP and PCT were significantly higher in patients with CAP than in the control group, respectively, NPY levels were significantly lower. Moreover, plasma levels of all neuropeptides and PCT were significantly higher in bacterial pneumonia patients compared to viral pneumonia patients. ROC analysis revealed that CGRP, SP and NPY had a diagnostic value in distinguishing viral and bacterial/mixed pneumonia. CONCLUSIONS: Our findings suggest that these neuropeptides may be implicated in pediatric CAP. CGRP, SP and NPY together may be a promising candidate in distinguishing viral and bacterial/mixed pneumonia, however, for this, further studies are needed. WHAT IS KNOWN: • Neurogenic inflammation contributes to the development and progression of respiratory inflammatory diseases such as chronic obstructive pulmonary disease and bronchial asthma. WHAT IS NEW: • Plasma levels of neurogenic inflammation related neuropeptides calcitonin gene-related peptide, substance P, vasoactive intestinal peptide and neuropeptide Y are changed in pediatric community-acquired pneumonia. Calcitonin gene-related peptide, substance P and neuropeptide Y are promising candidates in distinguishing viral and bacterial/mixed pneumonia.

Pseudomonas fluorescens pneumonia.

Pseudomonas fluorescens (P. fluorescens) is not generally considered a bacterial pathogen in humans; however, multiple culture-based and culture-independent studies have identified it in the indigenous microbiota of multiple body sites. We herein report a rare case of pneumonia caused by P. fluorescens. A man in his 80 s with chronic obstructive pulmonary disease and diabetes mellitus was diagnosed with stage II rectal cancer. He underwent laparoscopic surgery, and on the 6th postoperative day, he developed a high fever. Chest computed tomography revealed infiltration in the left lower lung. Gram staining of the sputum showed Gram-negative rods phagocytosed by neutrophils, suggesting postoperative nosocomial pneumonia. The patient was started on tazobactam/piperacillin, and his pneumonia quickly improved. Later, only P. fluorescens was detected in a sputum culture. It was susceptible to common antipseudomonal agents. Gram staining of P. fluorescens appears to show a slightly thicker and larger morphology in comparison to Pseudomonas aeruginosa. Although there have been reports of opportunistic infections caused by P. fluorescens in immunosuppressed patients, including those with advanced cancer, most have been bloodstream infections, with very few reports of pneumonia alone. Clinicians should be aware that patients, who are not necessarily immunosuppressed, may develop pneumonia caused by P. fluorescens.

Achromobacter pneumonia in a patient with advanced COPD, a diagnostic challenge.

Bacterial pneumonia causes significant morbidity and mortality especially in elderly and immunocompromised hosts. Achromobacter xylosoxidans denitrificans pneumonia is very rarely reported. However, the reported cases have been in patients who are either immunocompromised or have bronchiectasis. We hereby present a unique case of Achromobacter xylosoxidans denitrificans pneumonia in an immunocompetent patient with advanced chronic obstructive pulmonary disease (COPD). Our patient is a Caucasian male admitted with shortness of breath, fever and cough. Chest X-ray demonstrated right-sided infiltrates and he was treated with intravenous ceftriaxone and azithromycin. He was discharged home on oral amoxicillin-clavulanate 875-125 mg two times per day for a total of 7 days. Patient returned to emergency room after 5 weeks with persistent symptoms and chest X-ray revealed persistent right-sided infiltrate and sputum culture showed Achromobacter xylosoxidans denitrificans. The patient was started on oral levofloxacin 750 mg one time per day for 2 weeks with resolution of symptoms.

Acute glomerulonephritis with concurrent suspected bacterial pneumonia - is it the tip of the iceberg?

BACKGROUND: Post infectious glomerulonephritis is the most common glomerulopathy in children, occurring several weeks after nephritogenic streptococcal throat or skin infection. Reports of acute glomerulonephritis (AGN) occurring during active bacterial pneumonia in children are rare. The aim of this study was to evaluate the incidence of AGN concurrent with bacterial pneumonia in children. METHODS: We reviewed records of all children admitted with a diagnosis of pneumonia to the pediatric department in a single tertiary medical center between January 2015 and April 2023. Patients with bacterial pneumonia and concurrent glomerulonephritis were included. RESULTS: Eleven (0.98%) of 1,123 patients with bacterial pneumonia had concurrent AGN. All were males with a median age of 2.7 years (range 1-13). Mean time from bacterial pneumonia onset to acute glomerulonephritis symptoms was 2.7 ± 1.5 days. Five (45%) patients had evidence of pneumococcal infection. Hypertension was found in 10 (91%) patients. Mean trough eGFR was 43.5 ± 21.4 ml/min/1.73 m2 (range 11-73). Ten patients (91%) had low C3 levels. Median urinary protein-to-creatinine ratio was 2.5 mg/mg (IQR 2.15-14.75). All patients fully recovered. Microscopic hematuria was the last finding to normalize after a median of 29.5 days (IQR 17.25-38). CONCLUSION: AGN during bacterial pneumonia may be more frequent than previously recognized. Kidney prognosis was excellent in all patients. Prospective studies are needed to evaluate the impact of this condition.

Evaluation of the BioFire® FilmArray® Pneumonia plus Panel for Detecting Bacterial Etiological Agents of Lower Respiratory Tract Infections in an Oncologic Hospital. Comparison with Conventional Culture Method.

Conventional methods used to determine pneumonia pathogens are characterized by low sensitivity and long turnaround times. Introducing new tests with better parameters in patients at higher risk of infections is highly anticipated. The results of the conventional quantitative culture method (CM) in determining the bacterial etiology of pneumonia were compared with the results of the Pneumonia plus Panel test (PNP; BioFire® Diagnostics, USA) in 79 samples of bronchoalveolar lavage (BAL). Materials were collected from 79 patients with suspected pneumonia treated in an oncologic hospital due to solid tumors. Only 16/79 BAL samples (20.3%) were true positive (TP) for bacterial etiology in CM vs. 27/79 samples (34.2%) true positive in the PNP test. The total agreement between methods of interpreting the result (positive or negative) was 84.8%. The most prevalent pathogens in both methods were Staphylococcus aureus, followed by Escherichia coli, Pseudomonas aeruginosa, and Haemophilus influenzae. The PNP test identified several respiratory pathogens that were not grown in culture. The semiquantitative value reported by the PNP test was higher than that reported by culture. The PNP test vs. combined test (PNP test and CM methods) demonstrated positive predictive value (PPV) and negative predictive value (NPV) values of 100.0% and 98.1%, and the sensitivity and specificity were 96.4% and 100.0%. The PNP test is a good tool for determining the etiology of bacterial pneumonia and may support the care of an oncologic patient. However, further large-sample studies are needed to research in strictly defined groups of oncologic patients.

Ratio of procalcitonin/Simpson's dominance index predicted the short-term prognosis of patients with severe bacterial pneumonia.

Objective: The aim of this study was to explore the predictive value of the ratio of procalcitonin (PCT) in serum to Simpson's dominance index (SDI) in bronchoalveolar lavage fluid (BALF), in short-term prognosis of patients with severe bacterial pneumonia (SBP). Methods: This is a retrospective review of case materials of 110 patients with SBP who selected BALF metagenomic next-generation sequencing technique in the intensive care unit (ICU) of the Affiliated Hospital of Yangzhou University from January 2019 and July 2022. Based on the acute physiology and chronic health status score II, within 24 h after admission to the ICU, patients were divided into a non-critical group (n = 40) and a critical group (n = 70). Taking death caused by bacterial pneumonia as the endpoint event, the 28-day prognosis was recorded, and the patients were divided into a survival group (n = 76) and a death group (n = 34). The SDI, PCT, C-reactive protein (CRP), PCT/SDI, and CRP/SDI were compared and analyzed. Results: Compared with the non-critical group, the critical group had a higher PCT level, a greater PCT/SDI ratio, a longer ventilator-assisted ventilation time (VAVT), and more deaths in 28 days. Compared with the survivors, the death group had a higher PCT level, a lower SDI level, and a greater PCT/SDI ratio. The SDI level was significantly negatively correlated with the VAVT (r = -0.675, p < 0.05), while the PCT level, ratio of PCT/SDI, and ratio of CRP/SDI were remarkably positively correlated with VAVT (r = 0.669, 0.749, and 0.718, respectively, p < 0.05). The receiver operating characteristic (ROC) curves analysis showed that the area under ROC curves of PCT/SDI predicting patient death within 28 days was 0.851, followed by PCT + SDI, PCT, SDI, and CRP/SDI (0.845, 0.811, 0.778, and 0.720, respectively). The sensitivity and specificity of PCT/SDI for predicting death were 94.1% and 65.8%, respectively, at the optimal value (11.56). Cox regression analysis displayed that PCT/SDI (HR = 1.562; 95% CI: 1.271 to 1.920; p = 0.039) and PCT (HR = 1.148; 95% CI: 1.105 to 1.314; p = 0.015) were independent predictors of death in patients. Conclusion: The ratio of PCT/SDI was a more valuable marker in predicting the 28-day prognosis in patients with SBP.

Point-of-care procalcitonin testing for lower respiratory tract infection in pulmonary outpatient care has limited value.

Lower respiratory tract infections (LRTI) are frequently the reasons for patients to visit their general practitioners or lung specialists; however, physicians tend to prescribe antibiotics less frequently than necessary. A readily available biomarker could help distinguish between viral and bacterial cause of LRTI. The primary objective of our study was to determine the diagnostic accuracy of point-of-care testing (POCT) of procalcitonin (PCT) in identifying bacterial pneumonia in outpatients with LRTI. All patients aged 18 years or older with signs and symptoms of LRTI who visited a respiratory physician were included in the study and their PCT levels were measured. In 110 patients enrolled in the study, three patients (2.7%) had PCT values above the threshold of 0.25 µg/L without proven bacterial infection, in contrast to seven patients with typical radiological signs of pneumonia without elevated POCT PCT levels. The AUC for PCT for the detection of pneumonia was 0.56 (p=0.685). POCT PCT showed limited specificity and sensitivity in distinguishing pneumonia from bronchitis or exacerbation of chronic respiratory diseases. PCT is a marker of severe bacterial infections and not suitable for milder infections in outpatient care.

Identification of priority pathogens for aetiological diagnosis in adults with community-acquired pneumonia in China: a multicentre prospective study.

BACKGROUND: Community-acquired pneumonia (CAP) is a major public health challenge worldwide. However, the aetiological and disease severity-related pathogens associated with CAP in adults in China are not well established based on the detection of both viral and bacterial agents. METHODS: A multicentre, prospective study was conducted involving 10 hospitals located in nine geographical regions in China from 2014 to 2019. Sputum or bronchoalveolar lavage fluid (BALF) samples were collected from each recruited CAP patient. Multiplex real-time PCR and bacteria culture methods were used to detect respiratory pathogens. The association between detected pathogens and CAP severity was evaluated. RESULTS: Among the 3,403 recruited eligible patients, 462 (13.58%) had severe CAP, and the in-hospital mortality rate was 1.94% (66/3,403). At least one pathogen was detected in 2,054 (60.36%) patients, with two or more pathogens were co-detected in 725 patients. The ten major pathogens detected were Mycoplasma pneumoniae (11.05%), Haemophilus influenzae (10.67%), Klebsiella pneumoniae (10.43%), influenza A virus (9.49%), human rhinovirus (9.02%), Streptococcus pneumoniae (7.43%), Staphylococcus aureus (4.50%), adenovirus (2.94%), respiratory syncytial viruses (2.35%), and Legionella pneumophila (1.03%), which accounted for 76.06-92.52% of all positive detection results across sampling sites. Klebsiella pneumoniae (p < 0.001) and influenza viruses (p = 0.005) were more frequently detected in older patients, whereas Mycoplasma pneumoniae was more frequently detected in younger patients (p < 0.001). Infections with Klebsiella pneumoniae, Staphylococcus aureus, influenza viruses and respiratory syncytial viruses were risk factors for severe CAP. CONCLUSIONS: The major respiratory pathogens causing CAP in adults in China were different from those in USA and European countries, which were consistent across different geographical regions over study years. Given the detection rate of pathogens and their association with severe CAP, we propose to include the ten major pathogens as priorities for clinical pathogen screening in China.

Heparin-Binding Protein in Bronchoalveolar Lavage Fluid as a Biomarker for Discriminating Severe Bacterial and Viral Pneumonia in Critically Ill Children.

Objective: This study is aimed at exploring the ability to use heparin-binding protein (HBP) in bronchoalveolar lavage fluid (BALF) to differentially diagnose bacterial infection from viral infection for severe community-acquired pneumonia (CAP) in critically ill children. Methods: A total of 181 children with severe CAP admitted to the intensive care unit (ICU) were included in this study. BALF and blood samples were collected within the first 24 hours of admission. BALF HBP and interleukin-6 (IL-6) concentrations and neutrophil percentage (N%) as well as blood HBP, IL-6, procalcitonin (PCT), C-reactive protein, white blood cell concentrations and N% were measured. Results: Of the enrolled children, 126 were confirmed to have bacterial pneumonia, and 55 were confirmed to have viral pneumonia. Blood HBP and PCT concentrations and N% and BALF HBP and IL-6 concentrations and N% were significantly higher in bacterial pneumonia than in viral pneumonia (P < 0.05). In the bacterial pneumonia group, HBP and IL-6 concentrations and N% in BALF samples were all significantly higher than those in blood samples (P < 0.001), and BALF HBP and IL-6 concentrations and N% were correlated with blood HBP and IL-6 concentrations and N%, respectively (r = 0.439, 0.250, and 0.235, P < 0.01). BALF N% and blood N% were both correlated with BALF HBP concentrations and blood HBP concentrations, respectively (r = 0.622 and 0.346, P < 0.001). ROC analysis revealed that BALF HBP showed the best ability to predict bacterial pneumonia, with an area under the curve of 0.994, a sensitivity of 95.24%, and a specificity of 100.00% at its optimal cutoff value of 74.05 ng/mL. Conclusion: BALF HBP might be a promising biomarker for the early discrimination of bacterial infection from viral infection in critically ill children with severe CAP.

Values of combined C-reactive protein, procalcitonin and serum amyloid A in differential diagnosis of bacterial and non-bacterial community acquired pneumonia in children.

This research aimed to explore the clinical value of C-reactive protein (CRP), procalcitonin (PCT), and serum amyloid A (SAA) in early diagnosis of bacterial pneumonia. CRP, PCT, and SAA levels of children with bacterial pneumonia, children with non-bacterial pneumonia, and healthy children were compared. The sensitivity and specificity of CRP, PCT, and SAA in the diagnosis of bacterial pneumonia in children were compared. CRP, PCT, and SAA levels were significantly lower in healthy children when compared with children with Community acquired pneumonia (CAP). ROC analyses showed that CRP, PCT, and SAA all had good accuracy in distinguishing bacterial pneumonia from non-bacterial pneumonia. The combination of CRP, PCT, and SAA further enhanced the accuracy in distinguishing bacterial pneumonia from non-bacterial pneumonia. In conclusion, the expression levels of CRP, PCT, and SAA could indicate the status of bacterial pneumonia. The combined test of CRP, PCT, and SAA had the highest diagnostic accuracy.

The utility of procalcitonin for diagnosing bacteremia and bacterial pneumonia in hospitalized oncology patients.

PURPOSE: Procalcitonin (PCT) is an inflammatory marker elevated in bacteremia and bacterial pneumonia. We aimed to assess the real-world diagnostic accuracy of PCT in hospitalized patients with malignancy. METHODS: A retrospective cohort of 715 patients with cancer who had PCT measured during 750 admissions was analyzed. Diagnosis of bacteremia was determined using blood culture data. Diagnosis of bacterial pneumonia was based on radiographic infiltrate and/or sputum culture. PCT's performance was assessed using receiver operating characteristic (ROC) curves, sensitivity, and specificity. RESULTS: Patients had bacteremia, bacterial pneumonia, or both during 210 admissions (28%). PCT elevation above 0.5 ng/mL was significantly associated with diagnosed infection in the overall population (p < 0.0001) and in subgroups with solid tumor malignancies (p < 0.0001) and hematologic malignancies (p = 0.008). PCT was associated with infectious status in patients with any metastases, but not those with primary lung cancer, lung metastases, neuroendocrine tumors, febrile neutropenia, or history of bone marrow transplant (BMT). The area under the ROC curve for PCT in the overall population was 0.655. An ideal cutoff of 0.21 ng/mL led to a sensitivity of 60% and specificity of 59%. At cutoffs of 0.5 ng/mL and 0.05 ng/mL, PCT's sensitivity was 39% and 94%, while specificity was 79% and 17%, respectively. CONCLUSION: In this large cohort of hospitalized oncology patients, PCT elevation was associated with diagnosed bacteremia and/or bacterial pneumonia. However, specificity was limited, and PCT elevation was not associated with diagnosed infection in some subpopulations. While PCT may have some diagnostic utility for hospitalized oncology patients, values must be interpreted cautiously and considering clinical context.

Optimal cut-off value of serum procalcitonin in predicting bacterial infection induced acute exacerbation in chronic obstructive pulmonary disease: A prospective observational study.

OBJECTIVE: To explore the optimal cut-off value of serum procalcitonin (PCT) level in predicting bacterial infection in hospitalized patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). METHODS: 204 hospitalized patients with AECOPD were enrolled in this study. Their diagnoses and treatments followed routine protocols in Fu-Xing Hospital affiliated to Capital Medical University, Beijing, China. Extra blood samples were taken for serum PCT level testing and the results were blinded to the treating physicians. On discharge, clinical data were collected and the treating physicians made comprehensive analyses to determine whether the AECOPD were triggered by respiratory tract bacterial infection or non-bacterial causes according to the "new diagnostic criteria" defined in this study. In the AECOPD patients with bacterial infection, treating physicians decided whether they had bacterial pneumonia based on imaging studies. Receiver operating characteristic curve (ROC) was used to analyze the accuracy of serum PCT level in predicting bacterial infection. RESULTS: In the 173 AECOPD patients who did not have pneumonia, 115 had evidences of bacterial infection while 58 did not. The median PCT levels were 0.1(0.08, 0.18) ng/ml and 0.07 (0.05, 0.08) ng/ml for each group, which were statistically different. The proposed optimal cut-off value of serum PCT level in predicting bacterial infection was 0.08 ng/mL according to this study, with a sensitivity of 81%, specificity of 67% and area under the ROC curve (AUC) of 0.794. There were 31 AECOPD patients diagnosed with pneumonia, their median PCT level was 0.23 ng/mL. CONCLUSIONS: The serum PCT levels slightly increased in the majority of hospitalized patients with AECOPD compared with reference range. When PCT level was ≥0.08 ng/mL, AECOPD was more likely to be caused by bacterial infection. A significantly elevated PCT levels may indicate combination of AECOPD and bacterial pneumonia.

Biomarkers for iron metabolism among patients hospitalized with community-acquired pneumonia caused by infection with SARS-CoV-2, bacteria, and influenza.

Ferritin, the central iron storage protein, has attracted attention as a biomarker of severe COVID-19. Few studies have investigated regulators of iron metabolism in the context of COVID-19. The aim was to evaluate biomarkers for iron metabolism in the acute phase response to community-acquired pneumonia (CAP) caused by SARS-CoV-2 compared with CAP caused by bacteria or influenza virus in hospitalized patients. A cross-sectional study of 164 patients from the Surviving Pneumonia Cohort recruited between January 8, 2019 and May 26, 2020. Blood samples were collected at admission and analyzed for levels of C-reactive protein (CRP), ferritin, soluble transferrin receptor, erythroferrone, and hepcidin. Median (IQR) hepcidin was higher in SARS-CoV-2 with 143.8 (100.7-180.7) ng/mL compared with bacterial and influenza infection with 78.8 (40.1-125.4) and 53.5 (25.2-125.8) ng/mL, respectively. The median ferritin level was more than 2-fold higher in patients with SARS-CoV-2 compared with the other etiologies (p < 0.001). Patients with SARS-CoV-2 had lower levels of erythroferrone and CRP compared with those infected with bacteria. Higher levels of hepcidin and lower levels of erythroferrone despite lower CRP levels among patients with SARS-CoV-2 compared with those infected with bacteria indicate alterations in iron metabolism in patients with SARS-CoV-2 infection.

Evaluation of Procalcitonin's Utility to Predict Concomitant Bacterial Pneumonia in Critically Ill COVID-19 Patients.

Background: Historically, procalcitonin(PCT) has been used as a predictor of bacterial infection and to guide antibiotic therapy in hospitalized patients. The purpose of this study was to determine PCT's diagnostic utility in predicting secondary bacterial pneumonia in critically ill patients with severe COVID-19 pneumonia. Methods: A retrospective cohort study was conducted in COVID-19 adults admitted to the ICU between March 2020, and March 2021. All included patients had a PCT level within 72 h of presentation and serum creatinine of <1.5mg/dL. A PCT threshold of 0.5ng/mL was used to compare patients with high( ≥ 0.5ng/mL) versus low(< 0.5ng/mL) PCT. Bacterial pneumonia was defined by positive respiratory culture. A receiver operating characteristics (ROC) curve was utilized to evaluate PCT as a diagnostic test for bacterial pneumonia, with an area under the curve(AUC) threshold of 0.7 to signify an accurate diagnostic test. A multivariable model was constructed to identify variables associated with in-hospital mortality. Results: There were 165 patients included: 127 low PCT versus 38 high PCT. There was no significant difference in baseline characteristics, vital signs, severity of disease, or outcomes among low versus high PCT groups (all p > 0.05). While there was no difference in bacterial pneumonia in low versus high groups (34(26.8%) versus 12(31.6%), p = 0.562), more patients in the high PCT group had bacteremia (19(15%) versus 11(28.9%), p = 0.050). Sensitivity was 26.1% and specificity was 78.2% for PCT to predict bacterial pneumonia coinfection in ICU patients with COVID-19 pneumonia. ROC yielded an AUC 0.54 (p = 0.415). After adjusting for LDH>350U/L and creatinine in multivariable regression, PCT did not enhance performance of the regression model. Conclusions: PCT offers little to no predictive utility in diagnosing concomitant bacterial pneumonia in critically ill patients with COVID-19 nor in predicting increased severity of disease or worse outcomes including mortality.

Clinical utility of inflammatory biomarkers in COVID-19 in direct comparison to other respiratory infections-A prospective cohort study.

BACKGROUND: Inflammatory biomarkers are associated with severity of coronavirus disease 2019 (COVID-19). However, direct comparisons of their utility in COVID-19 versus other respiratory infections are largely missing. OBJECTIVE: We aimed to investigate the prognostic utility of various inflammatory biomarkers in COVID-19 compared to patients with other respiratory infections. MATERIALS AND METHODS: Patients presenting to the emergency department with symptoms suggestive of COVID-19 were prospectively enrolled. Levels of Interleukin-6 (IL-6), c-reactive protein (CRP), procalcitonin, ferritin, and leukocytes were compared between COVID-19, other viral respiratory infections, and bacterial pneumonia. Primary outcome was the need for hospitalisation, secondary outcome was the composite of intensive care unit (ICU) admission or death at 30 days. RESULTS: Among 514 patients with confirmed respiratory infections, 191 (37%) were diagnosed with COVID-19, 227 (44%) with another viral respiratory infection (viral controls), and 96 (19%) with bacterial pneumonia (bacterial controls). All inflammatory biomarkers differed significantly between diagnoses and were numerically higher in hospitalized patients, regardless of diagnoses. Discriminative accuracy for hospitalisation was highest for IL-6 and CRP in all three diagnoses (in COVID-19, area under the curve (AUC) for IL-6 0.899 [95%CI 0.850-0.948]; AUC for CRP 0.922 [95%CI 0.879-0.964]). Similarly, IL-6 and CRP ranged among the strongest predictors for ICU admission or death at 30 days in COVID-19 (AUC for IL-6 0.794 [95%CI 0.694-0.894]; AUC for CRP 0.807 [95%CI 0.721-0.893]) and both controls. Predictive values of inflammatory biomarkers were generally higher in COVID-19 than in controls. CONCLUSION: In patients with COVID-19 and other respiratory infections, inflammatory biomarkers harbour strong prognostic information, particularly IL-6 and CRP. Their routine use may support early management decisions.

Neumonía por Rothia mucilaginosa en un paciente inmunocomprometido posterior a un trasplante renal / Rothia mucilaginosa pneumonia in an immunocompromised patient after kidney transplant

Resumen Rothia mucilaginosa es una bacteria propia de la microbiota del tracto respiratorio superior, que se asocia en forma infrecuente a infecciones en pacientes inmunocomprometidos y con enfermedades pulmonares crónicas, principalmente neumonía y bacteriemia. Su tratamiento generalmente, se basa en el uso de antibacterianos β lactámicos. Se describe el caso de un paciente sometido a un trasplante renal con uso de fármacos inmunosupresores, que cursó con una infección diseminada por Cryptococcus neoformans. Tras el inicio de la terapia antifúngica, presentó un cuadro febril, con aparición de nuevos infiltrados radiológicos e insuficiencia respiratoria aguda, demostrándose en el estudio con lavado broncoalveolar, un cultivo positivo para R. mucilaginosa, descartándose otras etiologías. Evolucionó en forma favorable tras el uso de meropenem, con buena respuesta clínica y resolución de los infiltrados radiológicos.

Abstract Rothia mucilaginosa is a bacterium derived from the upper respiratory tract microbiota, which is rarely associated with infections in immunocompromised patients suffering chronic lung diseases, mainly pneumonia and bacteremia. Its treatment is generally based on the use of β-lactams. The case study of a kidney transplant patient using immunosuppressive drugs, who developed a disseminated Cryptococcus neoformans infection, is described. After starting antifungal therapy, he presented with fever, appearance of new radiological infiltrates and acute respiratory failure, demonstrating a positive culture for R. mucilaginosa in a study with bronchoalveolar lavage, ruling out other etiologies. He evolved favorably after the use of meropenem, with good clinical response and resolution of radiological infiltrates.

Olsenella uli-induced pneumonia: a case report.

BACKGROUND: Olsenella uli is anaerobic or microaerophilic bacteria, commonly found in oral cavity or gastrointestinal tract, which has not been reported to be associated with lower respiratory tract infection. Herein, we report the first case of Olsenella uli infection in the lung. CASE PRESENTATION: A 70-year-old male farmer with no history of other respiratory tract diseases developed a cough with bloody sputum three times a day without obvious causes or other concomitant symptoms. After a period of treatment with empirical antibiotic, his condition did not improve. The computed tomography (CT) and lung biopsy results indicated bilateral pneumonia, and Olsenella uli was identified by micromorphology, sequence analysis and mass spectrometry analysis recovered from sputum. Ceftazidime, a third generation cephalosporin was used for the treatment, and the patient recovered after 10 days. CONCLUSIONS: Our report suggests a causative role of gingival bacteria in the pathogenesis of pneumonia, thus early diagnosis and prompt antibiotic therapy may play a role in the treatment of Olsenella uli induced pneumonia.

Clinical profile and microbiological aetiology diagnosis in adult patients hospitalized with community-acquired pneumonia.

Early introduction of appropriate antibiotherapy is one of the major prognostic-modifying factors in community acquired pneumonia (CAP). Despite established guidelines for empirical therapy, several factors may influence etiology and, consequently, antibiotic choices. The aims of this study were to analyze the etiology of CAP in adults admitted to a northern Portugal University Hospital and evaluate the yield of the different methods used to reach an etiological diagnosis, as well as analyze of the impact of patient demographic and clinical features on CAP etiology. We retrospectively analyzed 1901 cases of CAP with hospitalization. The diagnostic performance increased significantly when blood and sputum cultures were combined with urinary antigen tests. The most frequent etiological agent was Streptococcus pneumoniae (45.7%), except in August, when it was overtaken by gram-negative bacilli (GNB) and Legionella pneumophila infections. Viral infections were almost exclusive to winter and spring. A negative microbiological result was associated with increasing age, non-smoking and lack of both blood/sputum cultures. Younger age was a predictor for S. pneumoniae, Influenza and L. pneumophila infections. Active smoking without any previously known respiratory disease was a risk factor for legionellosis. COPD was associated with Haemophilus influenzae cases, while dementia was typical in GNB and S. aureus patients. Diabetes mellitus (DM) and heart disease were negative predictors of S. pneumoniae and H. influenzae, respectively. P. aeruginosa was an independent risk factor for mortality (OR 13.02, 95% CI 2.94-57.7). This study highlights the importance of a comprehensive microbiological diagnostic workup and provides clues to predicting the most probable CAP causative agents, based on a patient's clinical profile. These may be taken into account when establishing first line antibiotherapy.