Eosinophilic Lung Diseases.

The eosinophilic lung diseases may manifest as chronic eosinophilic pneumonia, acute eosinophilic pneumonia, or as the Löffler syndrome (generally of parasitic etiology). The diagnosis of eosinophilic pneumonia is made when both characteristic clinical-imaging features and alveolar eosinophilia are present. Peripheral blood eosinophils are generally markedly elevated; however, eosinophilia may be absent at presentation. Lung biopsy is not indicated except in atypical cases after multidisciplinary discussion. The inquiry to possible causes (medications, toxic drugs, exposures, and infections especially parasitic) must be meticulous. Idiopathic acute eosinophilic pneumonia may be misdiagnosed as infectious pneumonia. Extrathoracic manifestations raise the suspicion of a systemic disease especially eosinophilic granulomatosis with polyangiitis. Airflow obstruction is frequent in allergic bronchopulmonary aspergillosis, idiopathic chronic eosinophilic pneumonia, eosinophilic granulomatosis with polyangiitis, and hypereosinophilic obliterative bronchiolitis. Corticosteroids are the cornerstone of therapy, but relapses are common. Therapies targeting interleukin 5/interleukin-5 are increasingly used in eosinophilic lung diseases.

Clinical characteristics, management, and outcome of eosinophilic pneumonia associated with daptomycin

Objective: The association between daptomycin exposure and eosinophilic pneumonia (EP) is mainly based on case reports. The purpose of this study was to evaluate the clinical characteristics and provide more evidence for better identify and management of daptomycin-induced eosinophilic pneumonia in clinical practice.MethodsLiterature from 1991 to October 31, 2021 on EP induced by daptomycin were collected for retrospective analysis.ResultsA total of 47 patients (40 male and 7 female) from 35 studies were included. The median age was 67 years (range 28–89), and 78.7% of patients were ≥60 years. Daptomycin was mainly used in patients undergoing osteoarticular infections (63.8%). Typical initial symptoms were fever (91.5%), cough (55.3%) and dyspnea (59.6%). The median onset time of symptom was 3 weeks. EP recurred in 14.9% of patients after the re-administration of daptomycin, and 57.1% of EP recurred within 24h. Most cases were accompanied by marked accumulation of eosinophils in peripheral (41 cases) and/or bronchoalveolar lavage fluid (27 cases). The main radiological features were pulmonary infiltration, ground glass opacity or consolidation in CT/CXR. All patients had symptom resolution after discontinuation of daptomycin except for one patient died due to the progression of the primary disease, the median time to symptoms relief was 3 days. Corticosteroids have been shown to help symptoms relief in some cases (59.6%).ConclusionDaptomycin-induced eosinophilic pneumonia is a rare and serious complication. Physicians should consider eosinophilic pneumonia as a differential diagnosis when receiving daptomycin therapy, particularly in elderly male patients. (AU)

Objetivo: La asociación entre la exposición a daptomicina y la neumonía eosinofílica (NE) se basa principalmente en informes de casos. El propósito de este estudio fue evaluar las características clínicas y proporcionar más evidencia para una mejor identificación y tratamiento de la NE inducida por daptomicina en la práctica clínica.MétodosSe recopiló literatura médica desde 1991 hasta el 31 de octubre de 2021 sobre NE inducida por daptomicina para un análisis retrospectivo.ResultadosSe incluyeron un total de 47 pacientes (40 hombres y 7 mujeres) de 35 estudios. La mediana de edad fue de 67 años (rango 28-89), y el 78,7% de los pacientes tenían≥60 años. La daptomicina se utilizó principalmente en pacientes con infecciones osteoarticulares (63,8%). Los síntomas iniciales típicos fueron fiebre (91,5%), tos (55,3%) y disnea (59,6%). La mediana del tiempo de aparición de los síntomas fue de 3 semanas. La NE reapareció en el 14,9% de los pacientes después de la readministración de daptomicina, y el 57,1% lo hizo dentro de las primeras 24h. La mayoría de los casos se acompañó de una marcada acumulación de eosinófilos en tejidos periféricos (91,1%)/pulmonares (7 casos) y/o líquido de lavado broncoalveolar (27 casos). Las principales características radiológicas fueron infiltración pulmonar, opacidad «en vidrio deslustrado» o consolidación en TC/CXR. Todos los pacientes tuvieron una resolución de los síntomas después de la interrupción de la daptomicina, excepto uno que falleció debido a la progresión de la enfermedad primaria; la mediana de tiempo hasta el alivio de los síntomas fue de 3 días. Se ha demostrado que los corticoides ayudan al alivio de los síntomas en algunos casos (59,6%).ConclusiónLa NE inducida por daptomicina es una complicación rara y grave. Los médicos deben considerar la NE como un diagnóstico diferencial cuando un paciente recibe tratamiento con daptomicina, particularmente en varones de edad avanzada. (AU)

Identification of Complex Pneumonia during the Outbreak of COVID-19: Bacterial Pneumonia Combined with Acute Eosinophilic Pneumonia in Patients with Maintenance Hemodialysis.

It is of crucial importance to diagnose patients in a timely and clear manner during the outbreak of COVID-19. Different causes of pneumonia makes it difficult to differentiate COVID-19 from others. Hemodialysis patients are a special group of people in this outbreak. We present a successfully treated case of a patient with maintenance hemodialysis from acute eosinophilic pneumonia for using meropenem when treating bacterial pneumonia, avoiding possible panic and waste of quarantine materials in dialysis centers.

Association between peripheral blood/bronchoalveolar lavage eosinophilia and significant oxygen requirements in patients with acute eosinophilic pneumonia.

BACKGROUND: We investigated the association between a combination of two markers, peripheral (PEC) and bronchoalveolar lavage (BAL) eosinophil percentage (BEP), and oxygen requirements in patients with acute eosinophilic pneumonia (AEP). METHODS: We retrospectively reviewed the medical records of patients with AEP treated at the Armed Forces Capital Hospital between May 2012 and May 2017. We used correlation analyses to assess the association between PEC/BEP and clinical outcomes in AEP patients. Receiver operating characteristic (ROC) curve analyses were used to calculate the cut-off value for BEP that categorised patients requiring a significant oxygen supply. The BAL/blood eosinophil (BBE) score was introduced to stratify patients with peripheral eosinophilia and elevated BEP. Clinical characteristics and outcomes were compared between the different groups. Multiple logistic regression was performed for significant oxygen requirements using two different models using age, C-reactive protein (CRP), smoking duration, and BBE score (model 1) and age, CRP, BEP, and PEC (model 2). RESULTS: Among the 338 patients, 99.7% were male, and their mean age was 20.4 ± 1.4 years. Only 0.6% of patients were never smokers and the mean number of smoking days was 26.2 ± 25.4. Correlation analyses revealed that both the PaO2/FiO2 ratio and duration of oxygen supply were associated with BEP. ROC curve analyses indicated a cut-off level of 41.5%. Patients with a high BBE score had favourable outcomes in terms of hypoxemia, hospital days, intensive care unit admission, oxygen supply days, and steroid treatment days. Multiple logistic regression revealed that BEP and BBE score tended to be associated with significant oxygen requirements. CONCLUSIONS: In this study, we revealed that both peripheral and BAL eosinophilia is associated with favourable outcomes in AEP patients.

Idiopathic acute eosinophilic pneumonia: A rare cause of hypoxic respiratory failure.

Idiopathic Acute Eosinophilic Pneumonia (IAEP) is a life-threatening cause of hypoxic respiratory failure. IAEP is challenging to diagnose as it may mimic infectious pneumonia or acute respiratory distress syndrome. Distinguishing IAEP from these alternatives is important; the mainstay of treatment for IAEP is corticosteroids, a therapy which might not otherwise be indicated. Patients treated appropriately usually experience a full recovery. In this case report we describe the presentation, evaluation, and management of a 19-year old male who presented to the emergency department (ED) in respiratory failure from IAEP. The patient was a military trainee who recently moved to the United States from Saudi Arabia. He also recently began smoking cigarettes for the first time, a known risk factor for IAEP. Upon initial presentation, the patient was in respiratory distress and had an oxygen saturation of 82% on room air. His ED diagnostic workup included chest X-ray showing diffuse interstitial thickening and chest computed tomography that demonstrated diffuse nodular opacification of pulmonary parenchyma. The patient was admitted to the intensive care unit (ICU) where bronchoscopy yielded cytology with 30% eosinophilia. The patient ultimately required 3 days of extra corporeal membrane oxygenation (ECMO) due to worsening hypoxic respiratory failure. After both intravenous and outpatient oral steroid treatments, the patient went on to have a full recovery with no ongoing respiratory issues. To our knowledge, this is the first case of IAEP requiring ECMO reported in the emergency medicine literature.

Eosinophilic pneumonia: A review of the previous literature, causes, diagnosis, and management.

Eosinophilic pneumonia (EP) is a rare disorder, comprising several heterogeneous diseases. Two major types of EP are acute eosinophilic pneumonia (AEP) and chronic eosinophilic pneumonia (CEP), both of which are characterized by marked accumulation of eosinophils in lung tissues and/or BAL fluid. AEP and CEP share some similarities in terms of pathophysiology, radiological findings, and treatment response to corticosteroids. However, they distinctly differ in etiology, clinical manifestations, and the nature of disease course. Especially, although AEP and CEP respond well to corticosteroids, relapse frequently occurs in patients with CEP, but rarely in those with AEP. Although CEP occasionally persists and becomes corticosteroid dependent, most patients with AEP completely recover. This article reviews previous studies and discusses the etiology, clinical manifestations, and treatment of AEP and CEP.

Age distribution and seasonality in acute eosinophilic pneumonia: analysis using a national inpatient database.

BACKGROUND: Acute eosinophilic pneumonia (AEP) is a rare inflammatory lung disease. Previous studies have shown that most patients with AEP are aged 20 to 40 years, whereas several case studies have included older patients with AEP. These studies also suggested that AEP is more prevalent in summer, but they were limited due to their small sample sizes. We therefore investigated the age distribution and seasonality among patients with AEP using a national inpatient database. METHODS: Using the Japanese Diagnosis Procedure Combination database, we identified patients with a recorded diagnosis of AEP from 1 July 2010 to 31 March 2015. We examined patient characteristics and clinical practices including age, sex, seasonal variation, length of stay, use of corticosteroids, use of mechanical ventilation, and in-hospital mortality. RESULTS: During the 57-month study period, we identified 213 inpatients with AEP. The age distribution of AEP peaked twice: at 15 to 24 years and 65 to 79 years. The proportion of patients with AEP was highest in summer for those aged < 40 years, whereas it was distributed evenly throughout the year for those aged ≥ 40 years. The interval from hospital admission to corticosteroid administration and the duration of corticosteroid use were significantly longer in the older than younger age group. CONCLUSIONS: The age distribution of patients with AEP was bimodal, and seasonality was undetected in older patients. Older patients may be more likely to have delayed and prolonged treatment.

Treatment of severe, uncontrolled eosinophilic asthma: Where we are heading.

OBJECTIVE: We sought to highlight how our understanding of the pathophysiology of severe asthma has evolved over time and discuss the role of biomarkers in treatment advances and emerging new therapies. DATA SOURCES: Nonsystematic PubMed literature search. STUDY SELECTION: Articles were selected based on areas of relevance to the classification of asthma by endotype, with an emphasis on the evolution of current treatment guidelines for severe asthma. RESULTS: Unlike older guidelines for the treatment of severe asthma, recent updates now distinguish between asthma severity and control. Moreover, asthma classification is shifting from phenotype to endotype with the development of biomarkers used to determine the mechanism driving a patient's disease. Many cases of severe asthma are associated with type-2 inflammation with elevated eosinophil counts in the airways. In recent studies, patients with severe, uncontrolled asthma and high eosinophil counts respond to biologic therapies targeting the type-2 signaling pathway and eosinophils themselves (eg, anti-IL-5 therapy). New treatments that address the pathophysiology of asthma offer a promising alternative to control severe asthma for patients who do not respond to traditional therapies. CONCLUSION: Understanding and using new treatment guidelines that separate the concepts of asthma severity and control may help clinicians to identify patients with severe, uncontrolled asthma who may benefit from new treatment options, such as anti-IL-5 therapies.

Acute eosinophilic pneumonia in the deployed military setting.

RATIONALE: Acute eosinophilic pneumonia (AEP) is a rare but important cause of severe respiratory failure most typically caused by cigarette smoking, but can also be caused by medications, illicit drugs, infections and environmental exposures. There is growing evidence that disease severity varies and not all patients require mechanical ventilation or even supplemental oxygen. OBJECTIVES: To compare patients with AEP treated at Landstuhl Regional Medical Center (LRMC) to those in other published series, and to provide recommendations regarding diagnosis and treatment of AEP. METHODS: A retrospective chart review was completed on forty-three cases of AEP which were identified from March 2003 through March 2010 at LRMC, Germany. RESULTS: Tobacco smoking was reported by 91% of our patients. Only 33% of patients in our series had a fever (temperature > 100.4 °F) at presentation. Peripheral eosinophilia (>5%) was present in 35% on initial CBC, but was seen in 72% of patients during their hospital course. Hypoxemia, as measured by PaO2/FiO2 ratio, seemed to be less severe in patients with higher levels of bronchoalveolar (BAL) eosinophilia percentage. CONCLUSIONS: Based on our experience and literature review, we recommend adjustments to the diagnostic criteria which may increase consideration of this etiology for acute respiratory illnesses as well as provide clinical clues we have found particularly helpful. Similar to recent reports of initial peripheral eosinophilia correlating with less severe presentation we found that higher BAL eosinophilia correlated with less severe hypoxemia.

Healthcare resource use and costs of severe, uncontrolled eosinophilic asthma in the UK general population.

BACKGROUND: Little is known about the prevalence of severe, uncontrolled eosinophilic asthma (SUEA) and associated costs. AIMS: We sought to determine the prevalence of SUEA and compare asthma-related healthcare resource use (HCRU) and associated costs with overall means for a general asthma population. METHODS: This cohort study evaluated anonymised medical record data (December 1989 through June 2015) from the Clinical Practice Research Datalink and the Optimum Patient Care Research Database to study UK patients with active asthma (diagnostic code and one or more drug prescriptions in the baseline year), aged 5 years and older, without concomitant COPD, and with recorded eosinophil count. SUEA was defined as two or more asthma attacks during 1 baseline year preceding a high blood eosinophil count (≥0.3×109/L) for patients prescribed long-acting ß2-agonist (LABA) and high-dosage inhaled corticosteroids (ICS) during baseline plus 1 follow-up year. We compared asthma-related HCRU and associated direct costs (2015 pounds sterling, £) during the follow-up year for SUEA versus the general asthma population. RESULTS: Of 363 558 patients with active asthma and recorded eosinophil count, 64% were women, mean (SD) age was 49 (21) years; 43% had high eosinophil counts, 7% had two or more attacks in the baseline year and 10% were prescribed high-dosage ICS/LABA for 2 study years. Overall, 2940 (0.81%; 95% CI 0.78% to 0.84%) patients had SUEA. Total mean per-patient HCRU and associated costs were four times greater for SUEA versus all patients (HCRU and cost ratios 3.9; 95% CI 3.7 to 4.1). CONCLUSIONS: Less than 1% of patients in a general asthma population had SUEA. These patients accounted for substantially greater asthma-related HCRU and costs than average patients with asthma.

Acute Eosinophilic Pneumonia. Causes, Diagnosis, and Management.

Acute eosinophilic pneumonia (AEP) is an uncommon acute respiratory illness of varying severity that includes presentation as acute respiratory distress syndrome with fatal outcome. AEP may be idiopathic, but identifiable causes include smoking and other inhalational exposures, medications, and infections. The pathogenesis of AEP is poorly understood but likely varies depending on the underlying cause. Airway epithelial injury, endothelial injury, and release of IL-33 are early events that subsequently promote eosinophil recruitment to the lung; eosinophilic infiltration and degranulation appear to mediate subsequent lung inflammation and associated clinical manifestations. Crucial for the diagnosis are the demonstration of pulmonary eosinophilia in the BAL fluid and the exclusion of other disease processes that can present with acute pulmonary infiltrates. Although peripheral blood eosinophilia at initial presentation may be a clue in suggesting the diagnosis of AEP, it may be absent or delayed, especially in smoking-related AEP. Optimal management of AEP depends on the recognition and elimination of the underlying cause when identifiable. The cessation of the exposure to the inciting agent (e.g., smoking), and glucocorticoids represent the mainstay of treating AEP of noninfectious origin. If AEP is recognized and treated in a timely manner, the prognosis is generally excellent, with prompt and complete clinical recovery, even in those patients manifesting acute respiratory failure.

Eosinophilic Lung Disease.

Eosinophils are involved in the pathogenesis of a number of lung diseases. Recent advances in eosinophil biology have now produced clinically applicable therapies that seek to counter eosinophilia in blood and lungs. This article reviews the basic biology of eosinophils and their role in mediating T-helper 2 cell responses. The current status of anticytokine therapy for eosinophilic lung disease is discussed. A clinical approach to eosinophilic lung disease based on symptoms and radiography is generated. The clinical significance of persistent eosinophilia in lung transplant patients and patients with asthma will receive special emphasis.

In vivo neutralization of α4 and ß7 integrins inhibits eosinophil trafficking and prevents lung injury during tropical pulmonary eosinophilia in mice.

Integrins regulate leukocyte trafficking during homeostasis and inflammatory conditions. However, the role of α4 and ß7 integrins in guiding eosinophil transmigration into the lungs during filarial manifestation of Tropical Pulmonary Eosinophilia (TPE) has not been explored. In this study, mice exhibiting TPE manifestations were administered with in vivo neutralizing antibodies against integrins α4 and ß7 or their combination and immuno-pathological parameters were evaluated. Results show an intact lung barrier, significantly lower lung inflammation and reduced eosinophil counts in the Bronchoalveolar lavage fluid and lungs of mice receiving anti-α4+ ß7 treatment. Reduced eosinophil peroxidase and ß-hexosaminidase activity, downregulation of inflammatory genes, lower production of inflammatory lipid intermediates like prostaglandins E2 and D2, leukotriene B4 and cysteinyl leukotrienes were also noted in anti-α4+ ß7 treated mice. Reduced accumulation of central memory, effector memory, regulatory T cells and lower production of IL-4, IL-5, and TGF-ß were other cardinal features of anti-α4+ ß7 treated mice lungs. Flow cytometry-sorted lung eosinophils from anti-α4+ ß7 treated mice showed higher apoptotic potential, downregulated anti-apoptotic gene Bcl-2, and exhibited reduced F-actin polymerization and calcium influx as compared to IgG controls. In summary, neutralization of α4+ ß7 integrins impairs the transmigration, activation and survival of eosinophils and reduces TPE induced pathology in mice lungs.

Acute Eosinophilic Pneumonia: Correlation of Clinical Characteristics With Underlying Cause.

BACKGROUND: Acute eosinophilic pneumonia (AEP) is an uncommon disease, often indistinguishable from ARDS or community-acquired pneumonia at initial presentation. AEP can be idiopathic, but identifiable causes include medications and inhalational exposures, including cigarette smoke. METHODS: Using a computer-assisted search, we retrospectively identified and reviewed the medical records of all patients diagnosed with AEP between January 1, 1998, and June 30, 2016, at our institution. Demographic and clinical data were extracted, including exposures (occupational, environmental, recreational, pharmacologic, and smoking), laboratory and radiologic findings, treatments, hospitalization (including ICU stay), and subsequent clinical course. RESULTS: Among 36 consecutive patients with AEP, 11 were smoking-related cases, six were medication-related cases and 19 were idiopathic. Smoking-related AEP included six first-time smokers and five ex-smokers who had resumed smoking after a period of abstinence. Patients with smoking-related AEP were younger compared with both medication-related and idiopathic AEP cases (median age: 22 vs 47.5 vs 55 years, respectively; P = .004). Patients with smoking-related AEP were less likely to be associated with peripheral eosinophilia at presentation (36% vs 50% vs 58%; P = .52) but more likely to be hospitalized (100% vs 50% vs 63%; P = .039), including a longer ICU stay, compared with medication-related and idiopathic cases. CONCLUSIONS: AEP is associated with a good prognosis when recognized and treated promptly. Compared with medication-related and idiopathic AEP, smoking-related AEP was less likely to be associated with peripheral eosinophilia at presentation but was characterized by more severe disease manifestations.

Pulmonary Eosinophilia From Inhaled Colistin.

We report the case of a patient with a history of chronic bronchiectasis that presented with new onset fatigue, shortness of breath, peripheral blood eosinophilia and infiltrates on chest radiograph. Eight days previously, she was prescribed inhaled colistimethate sodium 75 mg bid to prevent exacerbations of her respiratory condition. To our knowledge, our case is the first to show the clinical and radiologic features of inhaled-colistimethate-induced pulmonary eosinophilia. It also shows the rapid resolution of its features following treatment with oral corticosteroids. Eosinophilic lung reaction to inhaled colistin is rarely reported in the literature. Clinicians should be aware of this possible side effect.