Plasma metabolomics for the diagnosis and prognosis of H1N1 influenza pneumonia.

BACKGROUND: Metabolomics is a tool that has been used for the diagnosis and prognosis of specific diseases. The purpose of this study was to examine if metabolomics could be used as a potential diagnostic and prognostic tool for H1N1 pneumonia. Our hypothesis was that metabolomics can potentially be used early for the diagnosis and prognosis of H1N1 influenza pneumonia. METHODS: 1H nuclear magnetic resonance spectroscopy and gas chromatography-mass spectrometry were used to profile the metabolome in 42 patients with H1N1 pneumonia, 31 ventilated control subjects in the intensive care unit (ICU), and 30 culture-positive plasma samples from patients with bacterial community-acquired pneumonia drawn within the first 24 h of hospital admission for diagnosis and prognosis of disease. RESULTS: We found that plasma-based metabolomics from samples taken within 24 h of hospital admission can be used to discriminate H1N1 pneumonia from bacterial pneumonia and nonsurvivors from survivors of H1N1 pneumonia. Moreover, metabolomics is a highly sensitive and specific tool for the 90-day prognosis of mortality in H1N1 pneumonia. CONCLUSIONS: This study demonstrates that H1N1 pneumonia can create a quite different plasma metabolic profile from bacterial culture-positive pneumonia and ventilated control subjects in the ICU on the basis of plasma samples taken within 24 h of hospital/ICU admission, early in the course of disease.

Chest Radiological Findings of Patients With Severe H1N1 Pneumonia Requiring Intensive Care.

INTRODUCTION: A new strain of human influenza A (H1N1) virus originated from Mexico in 2009 and spread to more than 190 countries and territories. The World Health Organization (WHO) declared it a level 6 (highest level) pandemic. In August 2010, WHO announced that the H1N1 2009 influenza virus had moved into the postpandemic period. The WHO also declared that this flu strain is expected to continue to circulate as a seasonal virus "for some years to come." The objective of this study is to describe the chest radiographic and computed tomography (CT) findings of patients with severe H1N1 pneumonia admitted to the intensive care unit (ICU) during the 2009 pandemic. HYPOTHESIS: Patients with severe H1N1 pneumonia requiring ICU admission have extensive radiographic and CT abnormalities. METHODS: Eighteen patients, aged 23 to 62 (mean 41), admitted to the ICU at UCLA-Olive View Medical Center with a primary diagnosis of pandemic H1N1 infection, confirmed either via rapid influenza detection test or by real-time reverse transcriptase polymerase chain reaction assay, formed the study population. All patients had chest x-ray (CXR) within 24 hours of admission and 5 patients had CT examinations. In this retrospective study, images were evaluated for the pattern (ground-glass opacities, consolidation, reticular opacities, and nodular opacities), distribution (unilateral/bilateral, upper/middle/lower lung zone, and central/peripheral/peribronchovascular), and extent (focal/multifocal/diffuse; number of lung zones) of abnormalities. RESULTS: All (100%) patients had abnormal CXR and CT studies. The predominant radiographic findings were ground-glass opacities (16 of 18; 89%), consolidation (16 of 18; 89%), and reticular opacities (6 of 18, 33%). The radiographic abnormalities were bilateral in 17 (94%) patients; involved lower lung distribution in 18 (100%) patients, and mid and lower lung distribution in 16 (89%) patients. Radiographic abnormalities were peribronchovascular in 11 (61%) patients and multifocal in 10 (56%). Sixteen (89%) patients had extensive abnormalities involving 3 or more lung zones. The patients requiring mechanical ventilation had a higher incidence of bilateral, diffuse consolidation in a peribronchovascular distribution on chest radiographs. The predominant CT abnormalities were consolidation (5 of 5; 100%), ground-glass opacities (5 of 5; 100%), and nodular opacities (3 of 5, 60%). The CT findings were peribronchovascular and multifocal in 4 (80%) patients and extensive and bilateral in all (100%) patients. CONCLUSIONS: Patients with H1N1 pneumonia admitted to the ICU had bilateral, extensive CXR, and CT abnormalities. Consolidations and ground-glass opacities were the most common imaging findings, predominantly affecting mid and lower lung zones. Imaging abnormalities were peribronchovascular and multifocal in a majority of patients.

Six-Month Outcomes of Post-ARDS Pulmonary Fibrosis in Patients With H1N1 Pneumonia.

Background: Influenza virus is a common pathogen causing community-acquired pneumonia. After H1N1 infection, some patients present with rapid disease progression and various respiratory complications, especially immunocompromised patients and pregnant women. However, most patients have a favorable prognosis. Influenza viruses infect respiratory epithelial cells, leading to diffuse alveolar damage (DAD), which could induce secondary bacterial or fungal infections that could lead to serious complications, such as acute respiratory failure, severe pneumonia, pneumothorax, mediastinal emphysema, acute respiratory distress syndrome (ARDS) and post-ARDS fibrosis. Objective: The short-term mortality rate of ARDS is decreasing, and understanding survivors' posthospitalization outcomes is very important. Our aim was to evaluate the outcomes of 69 patients who survived H1N1 pneumonia with severe respiratory complications and abnormal CT findings and developed post-ARDS pulmonary fibrosis. Materials and methods: The 280 inpatients included in this trial had been diagnosed with H1N1 infection that was confirmed by pharyngeal sputum or swab tests. The data were collected from January 2018 to January 2020 in the First Affiliated Hospital of Zhengzhou University and the Sixth People's Hospital of Zhengzhou. Of these patients, 232 had CT findings indicating pulmonary fibrosis after H1N1 infection, and 69 survived and consented to participate in this study. 6°months after diagnosis, the 69 surviving patients were interviewed and underwent physical examinations, CT scans, 6°min walk tests, and quality-of-life evaluations (SF-36). We analyzed the baseline variables and six-month outcomes of post-ARDS pulmonary fibrosis in patients with H1N1 pneumonia. Results: Of the 69 surviving patients with post-ARDS pulmonary fibrosis, there were 24 females and 45 males, with a mean age of 53.7 ± 16.8°years; 18 patients (26%) had no underlying disease, and 14 (20%) patients had more than one underlying disease. The distance walked in 6°min increased from an average of 451.9°m at 3°months to 575.4°m at 6°months; the mean 36-Item Short Form Survey (SF-36) physical function score increased from an average of 75.3 at 3°months to 77.5 at 6°months; and the average CT score decreased from 31.3 at 3°months to 14.8 at 6°months. Treatment with systemic corticosteroids and the presence of an underlying disease were related to the CT score and the distance walked in 6°min. Conclusion: Among the survivors with pulmonary fibrosis after H1N1 influenza, the 6°min walk test and CT scores continued to be affected after 6°months. The 6°min walk distance and imaging findings improved during the first 6°months. The health-related QoL (HRQoL) scores of H1N1 pneumonia survivors were lower than those of sex- and age-matched controls.

Successful management of H1N1 related severe acute respiratory distress syndrome with noninvasive positive pressure ventilation.

Acute respiratory distress syndrome (ARDS) is a life threatening complication of H1N1 pneumonia. According to the Berlin conference guidelines, severe ARDS requires management with early invasive mechanical ventilation. Whether noninvasive positive pressure ventilation (NIPPV) should be attempted in patients with H1N1 pneumonia is still a matter of debate. We report the case of one patient with severe ARDS without other organ failure. The patient was managed successfully using NIPPV. Endotracheal intubation was avoided and the patient was discharged from the intensive care unit (ICU) after 10 days with a successful outcome. NIPPV can be useful in patients with isolated severe H1N1 ARDS provided early improvement of the oxygenation parameters is achieved. Patients with multiple organ failure or with persistent severe hypoxemia under noninvasive ventilation should be electively intubated and started on invasive mechanical ventilation.

Tracheal mucormycosis pneumonia: a rare clinical presentation.

This article reports an unusual case of tracheal mucormycosis following H1N1 pneumonia and reviews previously reported cases. A 40-y-old female with a 5-y history of diabetes mellitus, adequately controlled by oral hypoglycemic agents, developed tracheal mucormycosis after successful treatment for H1N1 pneumonia. The condition was diagnosed during workup for decannulation due to subglottic and upper tracheal obstruction by necrotic chewing gum-like tissue and cartilage. The patient was managed successfully by treatment with amphotericin B and surgical intervention in the form of laryngofissure and Montgomery tube placement. A review of the literature revealed only 5 previously reported cases of tracheal mucormycosis. A high degree of suspicion, early endoscopy and biopsy, histopathological evidence of the infection, and early institution of therapy are the keys to successful outcome.

Lobar flexible fiberoptic lung lavage: therapeutic benefit in severe respiratory failure in pulmonary alveolar proteinosis and influenza A H1N1 pneumonia.

Lobar fiberoptic lung lavage is a well-known procedure used in primary pulmonary alveolar proteinosis (PAP); the use of this procedure has increased in the recent years. This procedure has also been used in other pulmonary diseases such as desquamative interstitial pneumonia with good results. We describe a case of extremely severe respiratory failure due to concurrence of PAP and Influenza A H1N1 virus pneumonia which resolved with the help of this procedure. The patient, a 41-year-old woman, needed less mechanical ventilation after undergoing lobar fiberoptic bronchoscopic lavage. Moreover, a rapid and progressive improvement in the computed tomography of the lungs was observed. Flexibile fiberoptic bronchoscopic lobar lavage is a simple, safe procedure used not only in milder disease, but also in particular severe cases in which the physiological derangement of whole lung lavage would not be tolerated by patient or when extra-corporeal membrane oxygenation is not available.