Objective To explore the clinical characteristics of Chlamydia psittaci pneumonia. Methods From January 2020 to March 2023, 21 cases of Psittacosis from the First Affiliated Hospital of Nanjing Medical University were diagnosed via metagenomic next-generation sequencing (mNGS). They were divided into a severe group (n=10) and a non-severe group (n=11) based on diagnostic criteria for severe pneumonia, and the clinical presentation, secondary examination, treatment, and prognosis of the two groups were analyzed retrospectively. Results Among the 21 patients, there were 11 males and 10 females, with a mean age of (51.7±11.6) years. All patients had an acute onset and 12 had a confirmed history of exposure to poultry. The onset of the disease occurred in the autumn and winter seasons in 18 patients. All the patients were suffering from high fevers. Other symptoms included coughing, phlegm, tightness in the chest and fatigue. Laboratory examinations showed that the levels of leukocytes, neutrophil counts, C-reactive protein, procalcitonin, aminotransferase, creatine kinase, lactic dehydrogenase, brain natriuretic peptide precursors and D-dimer were significantly higher in the severe group than those in the non-severe group. Chest CT scans revealed varying levels of consolidation and spot shadowing with peripheral exudate in all patients. The patients in the severe group were more likely to have bilateral lung involvement, bilateral pleural effusion, cavity and mediastinal lymph node enlargement. Eleven patients received tetracycline alone, three received laudanum alone, two received respiratory quinolones alone, and five received a combination of two drugs including tetracycline. Chest CT at clinical follow-up showed absorption of lung lesions. Conclusions Chlamydia psittaci pneumonia usually occurs in the fall and winter, and most patients have a history of contact with poultry. Clinical presentation and imaging are not specified. The technology of mNGS enables early diagnosis of the disease, and neutrophil lymphocyte ratio, neutrophil-lymphocyte ratio and lactic dehydrogenase levels help assess the risk of severe disease.
Objective To explore the clinical value of metagenomic next-generation sequencing (mNGS) in the diagnosis and treatment of severe and complex infection of malignant hematological disorder. Methods The mNGS test results, traditional etiology test results and general clinical data of inpatients with malignant hematological disorder in the Department of Hematology, the Affiliated Hospital of Southwest Medical University between June 2020 and February 2022 were retrospectively analyzed. To explore the clinical application value of mNGS in the diagnosis and treatment of severe complicated infection of hematological disorder. Results A total of 21 patients were included. The samples included 18 peripheral blood samples, 2 pleural fluid samples and 1 alveolar lavage fluid sample. In the included patients, through mNGS, pathogenic bacteria were directly detected in 17 patients, including 8 fungi, 9 bacteria and 10 viruses, of which 9 were mixed infections. The positive rate (81.0% vs. 33.3%, P=0.002), sensitivity (85.7% vs. 30.0%), granulocytopenia (9 vs. 3 cases, P=0.031) and the types of pathogen (Z=−3.416, P=0.001) detected by mNGS were all higher than those by traditional method. The infection control of 17 patients improved in varying degrees after adjusting the treatment plan according to the test results. ConclusionsmNGS has significantly higher detection rate and sensitivity for bacteria, fungi, viruses and mixed infections. Compared with the traditional method, mNGS has more efficient characteristics. Its clinical application can further improve the diagnosis and treatment efficiency of severe complicated infection of malignant hematological disorder, and thus improve the survival rate of patients.
In recent years, with the wide application of metagenomics next-generation sequencing, more and more rare pathogens have been detected in our clinical work, including non-tuberculous Mycobacterium, Corynebacterium, Fusarium, Cryptococcus pneumoniae, human herpes virus, torque teno virus, parvovirus, Tropheryma whipplei, Bartonella, Chlamydia psittaci, etc. It is difficult to determine whether these rare pathogens are clinically significant and need treatment. This article puts forward some suggestions and discussions on the diagnosis and treatment of pulmonary infections with some rare pathogens.
Objective To explore the application value of metagenomic next-generation sequencing (mNGS) based on human sequencing in the clinical early diagnosis of lung cancer. Methods Four patients hospitalized with suspected lung infection were retrospectively analyzed, and the test results of bronchoalveolar lavage fluid (BALF) on mNGS of tumor metagenome, the routine clinical test results, and their clinical diagnosis and treatment information in between August 26, 2021, and December 18, 2021. Results Patient 1 was preliminarily diagnosed with lung cancer by referring to chest computed tomography (CT) imaging. Chest radiograph or CT in the other three patients showed bilateral lung CT and lamellar hyperintensities (patient 2), bilateral lung mass-like and lamellar hyperintensities (patient 3), and lung masses (patient 4), respectively. BALF samples from all 4 patients were detected with mNGS based on human tumor sequences, indicating tumor. In addition, the result in patient 3 also indicated white pseudofilamentous yeast infection consistent with clinical culture, and the result in patient 4 also showed infection of rhinovirus type A. Conclusion The second generation genome sequencing technology based on human sequence can not only assist clinical diagnosis of infection, but also provide detection datUM support for tumor early warning.
In recent years, due to the extensive usage of immunosuppressant and the rise of patients with cancers and organ transplantation, the incidence rate of invasive fungal infection, especially invasive pulmonary fungal infection, has increased. Besides the clinical manifestations, medical history and imaging, the diagnosis of pulmonary mycosis mainly depends on pathogen detection methods in clinical microbiology laboratory. However, due to the difficulty in fungi culturing and the low sensitivity of smear microscopy, better molecular biology methods are needed. To date, the emergence of metagenomic next-generation sequencing (mNGS) has improved the identification rate of pulmonary fungal infections. mNGS is significantly superior to traditional detection methods in rapid, accurate, and comprehensive determination of fungi from various clinical specimens, especially atypical fungi. However, some problems in mNGS method have to be addressed including sample collection, report interpretation, and its combination with traditional microbiology methods. With the in-depth discussion and solution of the above problems, mNGS will be indispensable to the etiological diagnosis of pulmonary invasive fungal infection.
Objective To summarize and explore the clinical features, diagnosis and treatment of severe pulmonary tuberculosis (TB). Methods One death case of pulmonary TB in The First Affiliated Hospital of Soochow University was analyzed, related publications of case reports and articles relevant on the analysis and study of pulmonary tuberculosis deaths from Pubmed between January 2012 and March 2022 were also reviewed. Results A 25-year-old female patient was admitted for "intermittent cough with sputum for more than 1 year, aggravated with chest tightness and shortness of breath for 5 days". She had no underlying disease. Pulmonary TB was diagnosed by TB bacterium smear and next-generation sequencing of bronchoalveolar lavage fluid. The patient was in shock compensation period and developed acute respiratory distress syndrome immediately after admission. Through active anti-tuberculosis, invasive mechanical ventilation, intra-aortic balloon counterpulsation and continuous renal replacement therapy, the disease continued to deteriorate and she died on the third day after admission. A total of 269 pulmonary TB deaths were retrieved. An analysis of 244 patients' past medical history showed that human immunodeficiency virus co-infection was the most common among young people and chronic diseases were the most common among the elderly. All 269 patients died of septic shock, respiratory failure and multiple organ dysfunction syndrome (MODS), among which hyponatremia was also a significant complication. The shortest time from admission to death was 7 days, while the longest average time was only 35 days. Conclusions Pulmonary TB could develop into septic shock and MODS with poor prognosis and high mortality. Health education on TB should be strengthened.
ObjectiveTo explore the application and clinical value of metagenomic next-generation sequencing (mNGS) combined with Omadacycline in the treatment of Refractory Mycoplasma pneumoniae pneumonia (RMPP).MethodsThe clinical data, relevant laboratory results, diagnosis and treatment process, and imaging outcomes of four patients diagnosed with Mycoplasma pneumoniae pneumonia through mNGS were analyzed. ResultsThe clinical symptoms at onset in all four patients were consistent with Mycoplasma pneumoniae pneumonia. After conventional treatment with macrolides, tetracyclines, or quinolone antibiotics, the symptoms showed no significant improvement, and there was a trend of radiological worsening. Following the confirmation of Mycoplasma pneumoniae infection through mNGS of bronchoalveolar lavage fluid, and due to various reasons preventing the use of the aforementioned drugs, omadacycline was ultimately chosen for treatment. Radiological improvements were observed in all cases, leading to a good prognosis and discharge. ConclusionsFor pneumonia cases where the infectious pathogen cannot be identified and conventional treatment has failed, mNGS can be utilized for early and accurate diagnosis. In cases of RMPP, Omadacycline can be employed as an alternative treatment to prevent delays in care and reduce the risk of complications.
ObjectiveTo explore the clinical value of metagenomic next-generation sequencing (mNGS) in diagnosis and treatment of periprosthetic joint infection (PJI) after total knee arthroplasty (TKA). MethodsBetween April 2020 and March 2023, 10 patients with PJI after TKA were admitted. There were 3 males and 7 females with an average age of 69.9 years (range, 44-83 years). Infection occurred after 8-35 months of TKA (mean, 19.5 months). The duration of infection ranged from 16 to 128 days (mean, 37 days). The preoperative erythrocyte sedimentation rate (ESR) was 15-85 mm/1 h (mean, 50.2 mm/1 h). The C reactive protein (CRP) was 4.4-410.0 mg/L (mean, 192.8 mg/L). The white blood cell counting was (3.4-23.8)×109/L (mean, 12.3×109/L). The absolute value of neutrophils was (1.1-22.5)×109/L (mean, 9.2×109/L). After admission, the joint fluid was extracted for bacterial culture method and mNGS test, and sensitive antibiotics were chosen according to the results of the test, and the infection was controlled in combination with surgery. Results Seven cases (70%) were detected as positive by bacterial culture method, and 7 types of pathogenic bacteria were detected; the most common pathogenic bacterium was Streptococcus lactis arrestans. Ten cases (100%) were detected as positive by mNGS test, and 11 types of pathogenic bacteria were detected; the most common pathogenic bacterium was Propionibacterium acnes. The difference in the positive rate between the two methods was significant (P=0.211). Three of the 7 patients who were positive for both the bacterial culture method and the mNGS test had the same results for the type of pathogenic bacteria, with a compliance rate of 42.86% (3/7). The testing time (from sample delivery to results) was (4.95±2.14) days for bacterial culture method and (1.60±0.52) days for mNGS test, and the difference was significant (t=4.810, P<0.001). The corresponding sensitive antibiotic treatment was chosen according to the results of bacterial culture method and mNGS test. At 3 days after the one-stage operation, the CRP was 6.8-48.2 mg/L (mean, 23.6 mg/L); the ESR was 17-53 mm/1 h (mean, 35.5 mm/1 h); the white blood cell counting was (4.5-8.1)×109/L (mean, 6.1×109/L); the absolute value of neutrophils was (2.3-5.7)×109/L (mean, 4.1×109/L). All patients were followed up 12-39 months (mean, 23.5 months). One case had recurrence of infection at 6 months after operation, and the remaining 9 cases showed no signs of infection, with an infection control rate of 90%. Conclusion Compared with bacterial culture method, mNGS test can more rapidly and accurately detect pathogenic bacteria for PJI after TKA, which is important for guiding antibiotics combined with surgical treatment of PJI.
Objective To analyze the clinical data of patients with Tropheryma whipplei pneumonia, and summarize the clinical characteristics, diagnosis, and treatment methods of Tropheryma whipplei pneumonia. Methods The data of Tropheryma whipplei pneumonia patients from three hospitals in Hunan Province between January 1, 2021 and October 1, 2022 were retrospectively collected. The clinical symptoms, laboratory examination, metagenomics next-generation sequencing (mNGS), CT imaging features, diagnosis and treatments of the included patients were analyzed. Results A total of 4 patients were included. Among them, there were 2 males and 2 females. The main manifestations were cough, expectoration, fever, and shortness of breath. There were 2 cases of diffuse ground glass opacity in both lungs, 1 case of pulmonary nodule, 1 case of pulmonary cavity, 1 case of pleural disease, 2 cases of pulmonary exudative lesions, and 1 case of mediastinal lymphadenectasis. The mNGS results showed that Tropheryma whipplei was detected in all 4 patients, and the median number of serial number (lower quartile, upper quartile) was 1 528 (1 480, 1 576). After anti infection treatment, 3 cases were treated effectively, and 1 case had poor treatment effect. Conclusions mNGS is an effective method to diagnose Tropheryma whipplei pneumonia. The measurement of serum lactate dehydrogenase level is helpful to evaluate the disease and determine the prognosis. Piperacillin tazobactam, meropenem and doxycycline are effective for this disease, while moxifloxacin and trimethoprim / sulfamethoxazole are not recommended because they may be naturally resistant. Without active etiological treatment, the disease may persist in migration and lead to extrapulmonary involvement.
The morbidity and mortality of pulmonary infection are high among infectious diseases worldwide. Rapid and accurate etiological diagnosis is the key to timely and effective treatment. Metagenomic next-generation sequencing (mNGS) technology has brokenthrough the limitations of traditional pathogenic microorganism detection methods and improved the detection rate of pathogens. In this paper, the application and advantages of mNGS technology in the diagnosis of bacteria, fungi, viruses and mixed infections in the lungs are analyzed, and the challenges and breakthroughs in RNA detection, wall breaking of firmicutes and host DNA clearance are described, in order to achieve targeted and accurate etiological diagnosis through mNGS, so as to effectively treat pulmonary infections.