Brief description of patient problem/setting (summarize the case very briefly)
Working in the main ER, you notice a patient getting triaged that has shortness of breath, fever, chills and fatigue. They tested negative for COVID/Flu and you are suspecting pneumonia. Standard of practice is getting a chest x-ray to confirm the diagnosis, but you have seen FAST exams being done for fluid accumulation in the chest and abdomen, and wonder if POC ultrasound can be used to look for consolidations like pneumonia in an acute situation.
Search Question: Clearly state the question (including outcomes or criteria to be tracked)
In patients with suspected community-acquired pneumonia, how does point-of-care ultrasound compare to chest X-ray in terms of diagnostic accuracy?
Question Type: What kind of question is this? (boxes now checkable in Word)
☐Prevalence ☐Screening ☒Diagnosis
☐Prognosis ☐Treatment ☐Harms
Assuming that the highest level of evidence to answer your question will be meta-analysis or systematic review, what other types of study might you include if these are not available (or if there is a much more current study of another type)? Please explain your choices.
– If meta-analysis or systematic review are not available, randomized controlled clinical trials will also offer great supporting evidence as they are carefully planned experiments, reduce the potential for bias, and allow for comparison between intervention and control groups.
– Cohort studies could also be used since they allow to follow the patients who have already received a particular treatment forward over time. This is not as reliable as randomized controlled clinical trials since patients might differ in ways other than in the variable that is being observed.
PICO search terms:
| P | I | C | O |
| Patients with community acquired pneumonia | Lung ultrasound | Chest X-ray | Diagnostic accuracy |
| Community acquired pneumonia | Point of care lung ultrasound | Chest radiograph | |
| CAP |
Search tools and strategy used:
Please indicate what data bases/tools you used, provide a list of the terms you searched together in each tool, and how many articles were returned using those terms and filters.
Explain how you narrow your choices to the few selected articles.
Results found:
TRIP Database
- Community acquired pneumonia AND Ultrasound (last 10 years) – 17
- Community acquired pneumonia AND Ultrasound AND Chest X-ray (last 10 years) – 11
PubMed
- Community acquired pneumonia AND Ultrasound (last 10 years) – 16
- Community acquired pneumonia AND Lung ultrasound AND Chest X-ray (last 10 years and Meta-analysis, Systemic Reviews and RCTs) – 6
Google Scholar
- Community acquired pneumonia AND Ultrasound AND Chest X-ray – 26,000
- Community acquired pneumonia AND Lung ultrasound AND Chest X-ray (last 10 years) – 16,900
Thankfully, many articles I found were either systematic reviews, meta-analysis, or a combination of both. One of the articles I found was published in January 2024, which makes it very topical for my discussion. Some of the articles I found were aimed at diagnosing community-acquired pneumonia in children, so I decided to add one of those articles in my discussion because I thought it was very important to include.
Identify at least 4 articles (or other appropriate reputable sources) that answer your specific question with the highest available level of evidence (you will probably need to look at more than 4 articles to get the 4 most focused and highest-level articles to address your question). Please make sure that they are Medline indexed.
Please post the citation and abstract for each article (to include the journal and authors’ names and date) and say why you chose it.
Please also note what kind of article it is (e.g. meta-analysis, cohort study, or independent blind comparison with gold standard of diagnosis, etc.).
At the bottom of each abstract, please comment on what your key points are from this article (including any points or concepts included in the article, but not present in the abstract – i.e. make the concepts understandable to the reader)
Please note that if the evidence is not in the abstract, you must clearly summarize the evidence in your posting.
| Citation: Abid, I., Qureshi, N., Lategan, N., Williams, S., & Shahid, S. (2024). Point-of-care lung ultrasound in detecting pneumonia: A systematic review. Canadian journal of respiratory therapy : CJRT = Revue canadienne de la therapie respiratoire : RCTR, 60, 37–48. https://doi.org/10.29390/001c.92182 |
| Type of article: Systematic Review |
| Abstract Purpose: Limited evidence exists to assess the sensitivity, specificity, and accuracy of point-of-care lung ultrasound (LUS) across all age groups. This review aimed to investigate the benefits of point-of-care LUS for the early diagnosis of pneumonia compared to traditional chest X-rays (CXR) in a subgroup analysis including pediatric, adult, and geriatric populations. Material and Methods: This systematic review examined systematic reviews, meta-analyses, and original research from 2017 to 2021, comparing point-of-care LUS and CXR in diagnosing pneumonia among adults, pediatrics and geriatrics. Studies lacking direct comparison or exploring diseases other than pneumonia, case reports, and those examining pneumonia secondary to COVID-19 variants were excluded. The search utilized PubMed, Google Scholar, and Cochrane databases with specific search strings. The study selection, conducted by two independent investigators, demonstrated an agreement by the Kappa index, ensuring reliable article selection. The QUADAS-2 tool assessed the selected studies for quality, highlighting risk of bias and applicability concerns across key domains. Statistical analysis using Stata Version 16 determined pooled sensitivity and specificity via a bivariate model, emphasizing LUS and CXR diagnostic capabilities. Additionally, RevMan 5.4.1 facilitated the calculation of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), offering insights into diagnostic accuracy. Results: The search, conducted across PubMed, Google Scholar, and Cochrane Library databases by two independent investigators, initially identified 1045 articles. Following screening processes, 12 studies comprised a sample size of 2897. LUS demonstrated a likelihood ratio of 5.09, a specificity of 81.91%, and a sensitivity of 92.13% in detecting pneumonia in pediatric, adult, and geriatric patients, with a p-value of 0.0002 and a 95% confidence interval, indicating diagnostic accuracy ranging from 84.07% to 96.29% when compared directly to CXR. Conclusion: Our review supports that LUS can play a valuable role in detecting pneumonia early with high sensitivity, specificity, and diagnostic accuracy across diverse patient demographics, including pediatric, adult, and geriatric populations. Since it overcomes most of the limitations of CXR and other diagnostic modalities, it can be utilized as a diagnostic tool for pneumonia for all age groups as it is a safe, readily available, and cost-effective modality that can be utilized in an emergency department, intensive care units, wards, and clinics by trained respiratory care professionals. |
| Key Points: This systematic review looked for articles across PubMed, Google Scholar, and the Cochrane Library databases in diagnosing pneumonia among pediatric, adult, and geriatric populations alikeThe timeframes that were looked at was between 2017-2021COVID-19 and its variants were excluded from the studyThe search yielded a total of 1045 articles that was then funneled down to 12 articles involved 2,897 patientsIn the geriatric populations, multiple studies showed a higher sensitivity and specificity for usage of lung ultrasound [LUS] versus chest X-rays [CXR] (LUS at 91% sensitivity and CXR at 76% sensitivity), with one of the articles dropping the sensitivity of CXR to 67%LUS could diagnose smaller consolidations in pediatric patients with a higher degree of accuracy than if the patient got a CXR48% of CXR were correctly diagnosed for community-acquired pneumonia, while 70% of patients who got a lung ultrasound were correctly diagnosedOverall, when the lung ultrasound was implemented, it came with a sensitivity at 92.13% with its ability to accurately identify positive cases across all age groups, while the chest X-ray displayed a sensitivity of 64% across the same groups leading to a faster diagnosis with ultrasound than with x-rayThe specificity of the lung ultrasound was 81.91%, while the specificity of the chest X-ray was higher at 94.3%, across all age groups |
| Why I chose it: I chose this article because it was the most recent article I could find in regards using ultrasound versus x-ray in diagnosing community-acquired pneumonia. This study was published early this year, so it is very topical for this discussion. The study not only covered diagnosing adults with CAP, but also geriatric and pediatric patients, which really showed how much more effective using ultrasound was against a chest x-ray across all age ranges. |
| Citation: Gentilotti, E., De Nardo, P., Cremonini, E., Górska, A., Mazzaferri, F., Canziani, L. M., Hellou, M. M., Olchowski, Y., Poran, I., Leeflang, M., Villacian, J., Goossens, H., Paul, M., & Tacconelli, E. (2022). Diagnostic accuracy of point-of-care tests in acute community-acquired lower respiratory tract infections. A systematic review and meta-analysis. Clinical microbiology and infection: the official publication of the European Society of Clinical Microbiology and Infectious Diseases, 28(1), 13–22. https://doi.org/10.1016/j.cmi.2021.09.025 |
| Type of article: Systematic Review and Meta-Analysis |
| Abstract Background: Point-of-care tests could be essential in differentiating bacterial and viral acute community-acquired lower respiratory tract infections and driving antibiotic stewardship in the community. Objectives: To assess diagnostic test accuracy of point-of-care tests in community settings for acute community-acquired lower respiratory tract infections. Data sources: Multiple databases (MEDLINE, EMBASE, Web of Science, Cochrane Library, Open Gray) from inception to 31 May 2021, without language restrictions. Study eligibility criteria: Diagnostic test accuracy studies involving patients at primary care, outpatient clinic, emergency department and long-term care facilities with a clinical suspicion of acute community-acquired lower respiratory tract infections. The comparator was any test used as a comparison to the index test. In order not to limit the study inclusion, the comparator was not defined a priori. Assessment of risk of bias: Four investigators independently extracted data, rated risk of bias, and assessed the quality using QUADAS-2. Methods of data synthesis: The measures of diagnostic test accuracy were calculated with 95% CI. Results: A total of 421 studies addressed at least one point-of-care test. The diagnostic performance of molecular tests was higher compared with that of rapid diagnostic tests for all the pathogens studied. The accuracy of stand-alone signs and symptoms or biomarkers was poor. Lung ultrasound showed high sensitivity and specificity (90% for both) for the diagnosis of bacterial pneumonia. Rapid antigen-based diagnostic tests for influenza, respiratory syncytial virus, human metapneumovirus, and Streptococcus pneumoniae had sub-optimal sensitivity (range 49%-84%) but high specificity (>80%). Discussion: Physical examination and host biomarkers are not sufficiently reliable as stand-alone tests to differentiate between bacterial and viral pneumonia. Lung ultrasound shows higher accuracy than chest X-ray for bacterial pneumonia at emergency department. Rapid antigen-based diagnostic tests cannot be considered fully reliable because of high false-negative rates. Overall, molecular tests for all the pathogens considered were found to be the most accurate. |
| Key Points: This systematic review and meta-analysis looked at how diagnostic testing accuracy was implemented across five different sections including physical examination (signs and symptoms), host biomarkers (CRP and procalcitonin (PCT)), imaging (chest X-ray, lung ultrasound), pathogen-based tests (RDT-Ab, RDT-Ag) and molecular tests (NAAT, PCR)421 articles were chosen, where 33 of those articles addressed imagingThe 33 studies included 4,901 participants and were all based out of the emergency departmentSkilled ultrasound techs looking for CAP had a sensitivity and specificity of 92% and 90%, respectively, while physicians who attended a short course on lung ultrasounds had a sensitivity and specificity of 89% and 88%, respectively, showing that the US exams did not significantly change with operator experience looking for CAP.Chest X-rays showed a suboptimal diagnostic performance with a sensitivity and specificity of 75% each, respectively. |
| Why I chose it: I chose this article because it was a systematic review and meta-analysis, and it was published a couple of years ago. This article also gave us a look into how accurate other modalities were in looking for respiratory tract infections, which was very eye-opening. As mentioned with the above article, lung ultrasound had a superior sensitivity and specificity against chest x-ray in accurately diagnosing a community-acquired pneumonia. I also thought it was very interesting to include that less experienced ultrasound technicians found CAP a lot faster than a Chest X-ray could. |
| Citation: Balk, D. S., Lee, C., Schafer, J., Welwarth, J., Hardin, J., Novack, V., Yarza, S., & Hoffmann, B. (2018). Lung ultrasound compared to chest X-ray for diagnosis of pediatric pneumonia: A meta-analysis. Pediatric pulmonology, 53(8), 1130–1139. https://doi.org/10.1002/ppul.24020 |
| Type of article: Meta-Analysis |
| Abstract Objective: Although a clinical diagnosis, the standard initial imaging modality for patients with concern for pediatric community acquired pneumonia (pCAP) is a chest x-ray (CXR), which has a relatively high false negative rate, exposes patients to ionizing radiation, and may not be available in resource limited settings. The primary objective of this meta-analysis is to evaluate the accuracy of lung ultrasound (LUS) compared to CXR for the diagnosis of pCAP. Methods: Data were collected via a systematic review of PubMed, EMBASE, and Web of Science with dates up to August 2017. Keywords and search terms were generated for pneumonia, lung ultrasound, and pediatric population. Two independent investigators screened abstracts for inclusion. PRISMA was used for selecting appropriate studies. QUADAS was applied to these studies to assess quality for inclusion into the meta-analysis. We collected data from included studies and calculated sensitivity, specificity, positive predictive value, and negative predictive values of CXR and LUS for the diagnosis of pCAP. Results: Twelve studies including 1510 patients were selected for data extraction. LUS had a sensitivity of 95.5% (93.6-97.1) and specificity of 95.3% (91.1-98.3). CXR had a sensitivity of 86.8% (83.3-90.0) and specificity of 98.2% (95.7-99.6). Variations between the studies included ultrasound findings diagnostic of pneumonia, study setting (inpatient vs emergency department) and inclusion of CXR in the reference standard for pneumonia. Conclusions: In our meta-analysis, lung ultrasound had significantly better sensitivity with similar specificity when compared to chest x-ray for the diagnosis of pediatric community acquired pneumonia. |
| Key Points: This meta-analysis looked at 12 studies across PubMed, EMBASE, and Web of Science that included 1,510 pediatric patientsPatients who were diagnosed with the lung ultrasound had a sensitivity and specificity of 95% eachThe sensitivity and specificity for the pediatric patients who were diagnosed with a chest x-ray were 86% and 98%, respectively112 cases of CAP were found on lung ultrasound, but were not found on chest x-ray35 cases of CAP were identified on chest x-ray but not on lung ultrasoundSmaller consolidations (a centimeter or less) were all missed by chest X-ray, but not with lung ultrasoundAs mentioned with the above article, physicians who had less experience with using lung ultrasound to find consolidations made less mistakes on the lung ultrasound than a patient who was given a chest x-ray looking for consolidations |
| Why I chose it: I chose this article because it was the only article that specifically talked about pediatric patients, who I wanted to include in this discussion. For pediatric patients, we generally use ultrasound to diagnose a plethora of different types of pathologies, and I believe diagnosing community-acquired pneumonia should be no different. This meta-analysis mirrors many of the same points that came from the adult and geriatric data that showed using POC lung ultrasound had a higher sensitivity and specificity in locating CAP versus using a chest x-ray that missed many smaller consolidations. |
| Citation: Ye, X., Xiao, H., Chen, B., & Zhang, S. (2015). Accuracy of Lung Ultrasonography versus Chest Radiography for the Diagnosis of Adult Community-Acquired Pneumonia: Review of the Literature and Meta-Analysis. PloS one, 10(6), e0130066. https://doi.org/10.1371/journal.pone.0130066 |
| Type of article: Systematic Review and Meta-Analysis |
| Abstract Lung ultrasonography (LUS) is being increasingly utilized in emergency and critical settings. We performed a systematic review of the current literature to compare the accuracy of LUS and chest radiography (CR) for the diagnosis of adult community-acquired pneumonia (CAP). We searched in Pub Med, EMBASE dealing with both LUS and CR for diagnosis of adult CAP, and conducted a meta-analysis to evaluate the diagnostic accuracy of LUS in comparison with CR. The diagnostic standard that the index test compared was the hospital discharge diagnosis or the result of chest computed tomography scan as a “gold standard”. We calculated pooled sensitivity and specificity using the Mantel-Haenszel method and pooled diagnostic odds ratio using the DerSimonian-Laird method. Five articles met our inclusion criteria and were included in the final analysis. Using hospital discharge diagnosis as reference, LUS had a pooled sensitivity of 0.95 (0.93-0.97) and a specificity of 0.90 (0.86 to 0.94), CR had a pooled sensitivity of 0.77 (0.73 to 0.80) and a specificity of 0.91 (0.87 to 0.94). LUS and CR compared with computed tomography scan in 138 patients in total, the Z statistic of the two-summary receiver operating characteristic was 3.093 (P = 0.002), the areas under the curve for LUS and CR were 0.901 and 0.590, respectively. Our study indicates that LUS can help to diagnosis adult CAP by clinicians and the accuracy was better compared with CR using chest computed tomography scan as the gold standard. |
| Key Points: The authors of this meta-analysis and systematic review looked through the PubMed and the EMBASE databases and found five studies overallThere was a total of 742 patientsThe sensitivity for diagnosing CAP with lung ultrasound versus chest x-ray was 95% and 77%, respectively The specificity for diagnosing CAP with lung ultrasound versus chest x-ray was 90% and 91%, respectively Diagnostic odds ratio (DOR) of a test is the ratio of the odds of positivity in subjects with disease relative to the odds in subjects without disease. The DOR for lung ultrasound was 151.19, and only 29.46 for chest x-ray |
| Why I chose it: I chose this article because it was another meta-analysis and systematic review. Although the sample size was smaller, I think the information was very similar to information given above. DOR, or diagnostic odds ratio, also showed that lung ultrasound showed more positivity in patients who had community-acquired pneumonia than other patients who didn’t by over five-fold. |
What is the clinical “bottom line” derived from these articles in answer to your question?
For decades, chest x-rays were the gold standard of diagnosing community-acquired pneumonia. As technology gave us newer modalities in looking for pathologies the POC lung ultrasound has been shown to be a more superior and effective modality in locating and correctly diagnosing CAP. Time and time again, as shown above with the different studies and articles, usage of a POC lung ultrasound to find CAP was more sensitive and specific than usage of a conventional chest x-ray. There was also data to back-up less experienced sonographers looking for consolidations found then versus what was found on CXR. If asked, I would definitely say that using a point-of-care lung ultrasound is a great tool to use to effectively find and diagnose community-acquired pneumonia over using a chest x-ray.
