Acute eosinophilic pneumonia: a cause of reversible, severe, noninfectious respiratory failure

Eosinophilic pneumonias in children: A review of the epidemiology, diagnosis, and treatment

Pediatric eosinophilic pneumonias (EPs) are characterized by a significant infiltration of the alveolar spaces and lung interstitium by eosinophils, with conservation of the lung structure. In developed countries, EPs constitute exceptional entities in pediatric care. Clinical symptoms may be transient (Löffler syndrome), acute (<1 month and mostly <7 days), or chronic (>1 month). Diagnosis relies on demonstration of alveolar eosinophilia on bronchoalveolar lavage, whether or not associated with blood eosinophilia. EPs are a heterogeneous group of disorders divided into: (i) secondary forms (seen mainly in parasitic infections, allergic bronchopulmonary aspergillosis, and drug reactions); and (ii) primary forms (eosinophilic granulomatosis with polyangiitis, hypereosinophilic syndrome, idiopathic chronic eosinophilic pneumonia, and idiopathic acute eosinophilic pneumonia). Despite their rarity, the etiological approach to EP must be well-defined as some causes can be rapidly life-threatening without initiation of the proper treatment. This approach (i) eliminates secondary forms, with comprehensive history taking and minimal biological assessment, (ii) is oriented in primary forms by the acute or chronic setting, and the existence of extrapulmonary symptoms. Treatment of primary forms has traditionally relied on corticosteroids, usually with a dramatic response. Specific treatments or the adjunction of corticosteroid-sparing treatment or immunosuppressors are currently being evaluated in order to improve the prognosis and the side effects associated with corticosteroid treatment in a pediatric setting.

Idiopathic eosinophilic pneumonia in children: the French experience

Background

Idiopathic eosinophilic pneumonia is extremely rare in children and adults. We present herein the first series describing the specificities of idiopathic chronic (ICEP) and acute (IAEP) eosinophilic pneumonia in children.

Methods

We retrospectively analyzed all cases of ICEP and IAEP in children that were retrieved from French Reference Centers for rare pediatric lung diseases.

Results

Five cases of pediatric ICEP were identified. Corticosteroid or immunosuppressive therapy dramatically improved the outcome in three cases. The remaining two cases had a persistent interstitial pattern with progressive development of cystic airspace lesions. Three cases of IAEP in adolescents were reported, with one requiring four days of extracorporeal membrane oxygenation.

Conclusion

ICEP is a rare disease with a polymorphic clinical presentation in children. We identified patients with persistent interstitial patterns progressing to cystic airspace regions, for which the boundaries with idiopathic interstitial pneumonias are difficult to establish. We therefore propose a specific pediatric definition and classification algorithm. IAEP in children remains an inflammatory reaction of the lung to an acute toxic exposure, mainly tobacco, as in adults. International studies are required to comprehensively assess the various clinical forms of the disease as well as the appropriate therapeutic regimens.

Acute Respiratory Distress Syndrome in a Patient with Acute Epstein-Barr Viral Infection and Eosinophilic Pneumonia

We report a case of acute respiratory distress syndrome associated with eosinophilic pneumonia in an adolescent with acute Epstein-Barr viral infection.

Smoking-related interstitial lung diseases

Cigarette smoke, a toxic collection of thousands of chemicals generated from combustion of tobacco, is recognized as the primary causative agent of certain diffuse interstitial and bronchiolar lung diseases. Most patients afflicted with these disorders are cigarette smokers, and smoking cessation has been shown to be capable of inducing disease remission and should occupy a pivotal role in the management of all smokers with these diffuse lung diseases. The role of pharmacotherapy with corticosteroids or other immunomodulating agents is not well established but may be considered in patients with progressive forms of smoking-related interstitial lung diseases.

[Acute respiratory failure revealing an idiopathic acute eosinophilic pneumonia: report of a pediatric case]

Eosinophilic pneumonias are a group of heterogeneous disorders, rarely reported in children. We describe a case of a 12-year-old boy hospitalized for an acute febrile respiratory failure. Chest radiograph showed bilateral diffuse infiltrates. A pulmonary eosinophilic infiltration was confirmed by a major blood eosinophilia at 33,800/mm(3) associated with increased eosinophilic rate (90%) on bronchoalveolar lavage fluid. Outcome improved markedly with mechanical ventilation and corticosteroid therapy. Laboratory screenings for parasitic or allergic disease were negative. Bone marrow smear and medullar caryotype eliminated an acute leukemia. No further visceral eosinophilic injury were found. Acute eosinophilic pneumonia should be included in etiological investigation of patients with acute respiratory distress syndrome (ARDS) even in young subjects.

Infection in Pediatric Acute Respiratory Distress Syndrome

Pediatric acute respiratory distress syndrome (ARDS) is a severe lung injury caused by pneumonia, sepsis, and trauma. ARDS results from inflammation and pulmonary capillary leak causing major changes in lung architecture and function. It has a low incidence, but its severity and duration cause major morbidity, mortality, and use of resources. Any organism can cause ARDS. Susceptible populations develop the syndrome more often and have worse outcomes. Aggressive diagnosis and intensive treatment are essential to good outcomes in ARDS caused by infection. The prognosis for survival is good, but morbidity after the syndrome is a major burden.

Pneumonia eosinofílica aguda com evolução para síndroma de dificuldade respiratória aguda: caso clínico

The Authors present a case of acute eosinophilic pneumonia (AEP) associated with severe acute respiratory distress syndrome in a previously healthy young adult, medicated with nitrofurantoin. AEP must be included in the differential diagnosis of community adquired pneumonia, as well as a cause of acute respiratory distress syndrome; its diagnosis is suggested by the presence of eosinophilic alveolitis in bronchoalveolar lavage fluid. The early diagnosis of AEP and corticosteroid therapy may be lifesaving.

Idiopathic acute eosinophilic pneumonia: a study of 22 patients

Idiopathic acute eosinophilic pneumonia (IAEP) is characterized by acute febrile respiratory failure associated with diffuse radiographic infiltrates and pulmonary eosinophilia. We conducted a multicenter retrospective study to characterize this rare clinical entity further and to improve its diagnostic criteria. A total of 13 male and 9 female patients (mean age: 29 +/- 15.8 years) presented with severe hypoxemia (Pa(O2)/fraction of inspired oxygen ratio = 156 +/- 74.1) requiring mechanical ventilation in 14 cases. Bronchoalveolar lavage was performed on all patients and showed 54.4 +/- 19.2% eosinophils on differential cell count, but no open-lung biopsies were done. No clinical differences were found between patients seen at less than 7 days (n = 15) or at 7 to 31 days (n = 7) from the onset of IAEP. A total of 12 patients met the clinical criteria of acute lung injury, and eight of these patients met the criteria for acute respiratory distress syndrome. All patients recovered, either spontaneously (6) or on corticosteroid treatment (16). No relapses occurred. We conclude that: (1) diagnostic criteria of IAEP are compatible with a duration of symptoms for up to 1 month, but the response to corticosteroid treatment is not diagnostic because of possible spontaneous recovery; (2) IAEP should be considered as differential diagnosis of acute lung injury or acute respiratory distress syndrome; (3) bronchoalveolar lavage eosinophilia obviates the need for lung biopsy in IAEP.

Acute eosinophilic pneumonia in a New York City firefighter exposed to World Trade Center dust

We report a sentinel case of acute eosinophilic pneumonia in a firefighter exposed to high concentrations of World Trade Center dust during the rescue effort from September 11 to 24. The firefighter presented with a Pa(O2) of 53 mm Hg and responded to oxygen and corticosteroids. Computed tomography scan showed patchy ground glass density, thickened bronchial walls, and bilateral pleural effusions. Bronchoalveolar lavage recovered 70% eosinophils, with only 1% eosinophils in peripheral blood. Eosinophils were not degranulated and increased levels of interleukin-5 were measured in bronchoalveolar lavage and serum. Mineralogic analysis counted 305 commercial asbestos fibers/10(6) macrophages including those with high aspect ratios, and significant quantities of fly ash and degraded fibrous glass. Acute eosinophilic pneumonia is a rare consequence of acute high dust exposure. World Trade Center dust consists of large particle-size silicates, but fly ash and asbestos fibers may be found in bronchoalveolar lavage cells.

Pediatric bronchoscopy

Diagnostic flexible endoscopy for pediatric respiratory diseases is performed in many centers. Technical advances have resulted in performance of interventional bronchoscopies, and new diagnostic indications are being explored. Indications with documented clinical benefit include congenital or acquired progressive or unexplained airway obstruction. Pulmonary infections in immunodeficient children who do not respond to empirical antibiotic treatment may be diagnosed by bronchoscopy and bronchoalveolar lavage (BAL). The potential usefulness of bronchoscopy and BAL for managing chronic cough, wheeze, or selected cases with asthma or cystic fibrosis requires further study. The use of transbronchial biopsies (TBB) is established in pediatric lung transplantation. The role of TBB in the diagnosis of chronic interstitial lung disease in children remains to be determined. For a number of interventional applications, rigid endoscopy is required, and pediatric bronchoscopists should be trained in its use. Complications in pediatric bronchoscopy are rare, but severe nosocomial infection or overdosing with local anesthetics has occurred. The issues of quality control, video documentation, interobserver variability of findings, and educational standards will have to be addressed in the future as bronchoscopy use becomes less restricted to only large pediatric pulmonary units.

Pulmonary infiltrates with eosinophilia syndromes in children

Pulmonary infiltrates with eosinophilia (PIE) are a group of heterogeneous disorders having the common findings of lung disease and eosinophilia in the peripheral blood, bronchoalveolar lavage fluid, or pulmonary interstitium. Eleven cases of PIE syndromes were identified through a retrospective and prospective chart review: drug-induced (2), acute eosinophilic pneumonia (3), infant pulmonary eosinophilia (2), parasite-induced (2), Churg-Strauss syndrome (1), and atypical chronic PIE (1). Patient demographics, clinical presentation, and disease severity varied considerably among groups. Therapeutic interventions included bronchodilators (10), oxygen (7), corticosteroids (9), and mechanical ventilation (3). A single patient with acute eosinophilic pneumonia died. Our experience suggests that PIE syndromes are rare in childhood and that clinical presentation can vary widely. Because of the potential for significant morbidity and mortality, aggressive diagnostic evaluations are warranted, particularly in children with respiratory failure of unknown etiology.