Fever after bronchoscopy: serum procalcitonin enables early diagnosis of post-interventional bacterial infection

Comparison of the upper and lower airway microbiome in early postoperative lung transplant recipients

The upper and lower respiratory tract may share microbiome because they are directly continuous, and the nasal microbiome contributes partially to the composition of the lung microbiome. But little is known about the upper and lower airway microbiome of early postoperative lung transplant recipients (LTRs). Using 16S rRNA gene sequencing, we compared paired nasal swab (NS) and bronchoalveolar lavage fluid (BALF) microbiome from 17 early postoperative LTRs. The microbiome between the two compartments were significantly different in Shannon diversity and beta diversity. Four and eight core NS-associated and BALF-associated microbiome were identified, respectively. NS samples harbored more Corynebacterium, Acinetobacter, and Pseudomonas, while BALF contained more Ralstonia, Stenotrophomonas, Enterococcus, and Pedobacter. The within-subject dissimilarity was higher than the between-subject dissimilarity, indicating a greater impact of sampling sites than sampling individuals on microbial difference. There were both difference and homogeneity between NS and BALF microbiome in early postoperative LTRs. High levels of pathogens were detected in both samples, suggesting that both of them can reflect the diseases characteristics of transplanted lung. The differences between upper and lower airway microbiome mainly come from sampling sites instead of sampling individuals.

IMPORTANCE

Lung transplantation is the only therapeutic option for patients with end-stage lung disease, but its outcome is much worse than other solid organ transplants. Little is known about the NS and BALF microbiome of early postoperative LTRs. Here, we compared paired samples of the nasal and lung microbiome from 17 early postoperative LTRs and showed both difference and homogeneity between the two samples. Most of the "core" microbiome in both NS and BALF samples were recognized respiratory pathogens, suggesting that both samples can reflect the diseases characteristics of transplanted lung. We also found that the differences between upper and lower airway microbiome in early postoperative LTRs mainly come from sampling sites instead of sampling individuals.

Clinical significance of procalcitonin in critically ill patients with pneumonia receiving bronchoalveolar lavage

Background

As a useful tool in intensive care units (ICU), fiberoptic bronchoscopy (FOB) may cause a deterioration of infection. This study is to investigate the clinical significance of procalcitonin (PCT) in critically ill patients with severe pneumonia receiving bronchoalveolar lavage (BAL).

Methods

A retrospective case-control study was performed in a single respiratory ICU (RICU) with 6-bed. Critically ill patients with severe pneumonia admitted to RICU were consecutively reviewed from March 2017 to October 2019. Chi-square test, Wilcoxon test, Mann Whitney U-test, Kaplan-Meier survival analysis or Cox's proportional hazards regression model was used as appropriate.

Results

A total of 72 eligible patients were included in the final analysis, 51 of which received BAL performed by FOB. Serum levels of PCT in group received BAL is markedly increased at 24 hours after FOB (p<0.001). Forty-eight hours later, BAL group with decreased serum levels of PCT had less SOFA score and decreased mortality compared with those with increased serum levels of PCT. Furthermore, Kaplan-Meier analysis indicated that patients with decreased serum levels of PCT had improved survival rate during hospital (Breslow test, p=0.041). However, increased PCT after BAL was not an independent risk factor for in-hospital mortality (hazard ratio: 1.689, 95% CI(0.626 ,4.563), p=0.301).

Conclusions

BAL performed by FOB increased serum levels of PCT. However, PCT levels decreased at 48 hours after BAL predicted a good prognosis of patients with severe pneumonia.

Construction of a Risk Prediction Model for Fever After Painless Bronchoscopy

Background

The aim of this study was to construct a risk prediction model for fever after painless bronchoscopy.

Material/Methods

A total of 188 patients were included, and a self-designed data collection form was used. By collecting relevant clinical data of patients before, during, and after the painless bronchoscopy, the influencing factors were analyzed through univariate analysis, and multiple logistic regression analysis was performed to construct the prediction equation, which was tested by ROC curve analysis.

Results

Of the 188 patients undergoing painless bronchoscopy, 49 had postoperative fever, and the incidence rate was 26.0%. The prediction probability model was: P=e^x/1+e^x, where e is the natural logarithm, X=−4.337+0.020×(CRP)+1.014 (whether the examination time was greater than 30 minutes)+1.912×(whether remifentanil was used during anesthesia)+1.514×(whether nausea or vomiting occurred during surgery or during recovery). The prediction sensitivity and specificity were 78.26% 76.72%, respectively.

Conclusions

Use of this risk prediction model of fever after painless bronchoscopy can improve the recognition of people at high risk of postoperative fever, and it has good ability to guide clinical nursing observation and early screening of fever after painless bronchoscopy.

Impact of diagnostic bronchoscopy in burned adults with suspected inhalation injury

INTRODUCTION

Inhalation injury is a common complication of thermal trauma. Fiberoptic bronchoscopy (FOB) is regarded as current standard practice in diagnosing and grading inhalation injury. Nonetheless, its predictive value in terms of therapeutic decision-making and clinical outcome is controversial.

METHODS

Adult burn patients with inhalation injury (InI) were selected from the National Burn Repository of the American Burn Association. Subjects were propensity score pair-matched based on injury severity and grouped based on whether or not FOB had been performed (FOB, CTR, respectively). Mortality, incidence of pneumonia, length of hospitalization, length of ICU stay and dependency on mechanical ventilation were compared between the two groups.

RESULTS

3014 patients were matched in two groups with a mean TBSA of 22.4%. There was no significant difference in carboxyhemoglobin fraction at admission. Patients, who underwent FOB on admission had a significantly increased incidence of pneumonia (p < 0.001), mortality (p < 0.05), length of hospitalization (p = 0.002), ICU stay (p < 0.001) and duration of mechanical ventilation (p = 0.006). In a subgroup analysis of patients with TBSA of at least 20%, incidence of pneumonia was significantly higher in the FOB group (p < 0.001) and longer mechanical ventilation was required (p = 0.036).

DISCUSSION

Diagnosis and grading of InI through FOB is the current standard, although its predictive value regarding key outcome parameters and therapeutic decision-making, remains unclear. The potential procedural risk of FOB itself should be considered. This study demonstrates correlations of FOB with major clinical outcomes in both a general collective of burned adults as well as severely burned adults. Although these findings must be interpreted with caution, they may induce further research into potential harm of FOB and critical review of routine diagnostic FOB in suspected inhalation injury in thermally injured patients.

Comparison of paired human nasal and bronchial airway epithelial cell responses to rhinovirus infection and IL-13 treatment

BACKGROUND

Because of its advantage as a minimally invasive procedure, nasal brushings have been increasingly used and proposed as a valuable approach to study lower airway diseases in lieu of bronchial epithelial cells. However, there is limited or conflicting evidence pertaining to whether nasal samples can be surrogates to bronchial samples. The goal of the present study is to test whether nasal epithelial cells have similar antiviral and inflammatory responses to IL-13 treatment and rhinovirus infection, a condition mimicking virally induced asthma exacerbation. Nasal and bronchial airway epithelial cells taken from the same patient were cultured under submerged and air-liquid interface (ALI) culture in the absence or presence of rhinovirus and IL-13 treatment. Inflammatory cytokines IP-10 and eotaxin-3, antiviral gene Mx1 and viral levels were measured.

RESULTS

In the absence of IL-13 treatment, nasal and bronchial cells showed a similar IP-10 response in both ALI and submerged cultures. Under the ALI culture, short term (e.g., 3 days) IL-13 treatment had a minimal effect on viral and Mx1 levels in both cell types. However, prolonged (e.g., 14 days) IL-13 treatments in both cell types decreased viral load and Mx1 expression. Under the submerged culture, IL-13 treatment in both cell types has minimal effects on viral load, IP-10 and Mx1. IL-13-induced eotaxin-3 production was similar in both types of cells under either submerged or ALI culture, which was not affected by viral infection.

CONCLUSIONS

Our data suggest that nasal epithelial cells could serve as a surrogate to bronchial epithelial cells in future studies aimed at defining the role of type 2 cytokine IL-13 in regulating pro-inflammatory and antiviral responses.