Diagnosis Of Organizing Pneumonia Research Articles

Organizing pneumonia is associated with molecular allograft injury and the development of antibody-mediated rejection

The association between organizing pneumonia (OP) after lung transplantation with the development of acute rejection (AR) remains undefined. In addition, molecular allograft injury, as measured by donor-derived cell-free DNA (dd-cfDNA), during episodes of OP and its relationship to episodes of AR, chronic lung allograft dysfunction (CLAD), or death is unknown. This multicenter, prospective cohort study collected serial plasma samples from 188 lung transplant recipients for dd-cfDNA at the time of bronchoscopy with biopsy. Multivariable Cox regression was used to analyze the association between OP with the development of AR (antibody-mediated rejection (AMR) and acute cellular rejection (ACR)), CLAD, and death. Multivariable models were performed to test the association of dd-cfDNA at OP with the risk of AR, CLAD, or death. In multivariable analysis, OP was associated with increased risk of AMR (hazard ratio (HR)=2.26, 95% confidence interval (CI) 1.04-4.92, p=0.040) but not ACR (HR=1.29, 95% CI: 0.66-2.5, p=0.45) or the composite outcome of CLAD or death (HR=0.88, 95% CI, 0.47-1.65, p=0.69). Median levels of dd-cfDNA were higher in OP compared to stable controls (1.33% vs 0.43%, p=0.0006). Multivariable analysis demonstrated that levels of dd-cfDNA at diagnosis of OP were associated with increased risk of both AMR (HR=1.29, 95% CI 1.03-1.62, p=0.030) and death (HR=1.16, 95% CI, 1.02-1.31, p=0.026). OP is independently associated with an increased risk of AMR but not CLAD or death. The degree of molecular allograft injury at the diagnosis of OP may further predict the risk of AMR and death.

Exploring Diverse Presentations of Cryptogenic Organizing Pneumonia: A Case Series

Cryptogenic Organizing Pneumonia (COP), the idiopathic form of Organizing Pneumonia (OP) previously known as “bronchiolitis obliterans organizing pneumonia,” is a well-documented medical condition with distinct clinicoradiological features and diagnostic criteria. COP can exhibit a diverse range of radiological presentations, including multiple patchy alveolar opacities (typical pattern), a solitary focal lesion, or diffuse bilateral infiltration. Corticosteroid therapy is typically effective in achieving rapid clinical and imaging improvement, but caution must be exercised in cases of active infections where corticosteroids are contraindicated, posing a challenge for OP diagnosis. This case series emphasizes the need for healthcare providers to be knowledgeable about the various atypical clinical manifestations of COP, recognize the diverse and uncommon radiological presentations that may mimic other pulmonary pathologies, and consider COP in the differential diagnosis to ensure appropriate management and enhance patient outcomes.

Secondary Organising Pneumonia Among COVID-19 Patients: A Retrospective Case-Control Study.

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Secondary organising pneumonia (OP) induced by SARS-CoV-2 infection is a recently recognised complication of COVID-19. We aimed to evaluate the prevalence of OP among hospitalised patients with COVID-19 pneumonia and to assess whether disease severity and other clinical factors and comorbidities are correlated with OP development.We conducted a retrospective case-control study including hospitalised patients due to COVID-19 who performed a chest CT scan during hospitalisation and compared patients with clinical and radiological evidence of OP to patients without evidence of OP. Demographics, comorbidities, disease severity, dexamethasone/remdesivir treatment, laboratory results, and outcomes were compared between groups.One hundred fifteen patients were included, of whom 48 (41.7%) fulfilled clinical and imaging criteria for OP. Among OP patients, the most common chest CT-scan findings were consolidations, arciform condensations, and subpleural bands. OP patients had longer hospitalisation (19.5 vs 10 days, p=0.002) and more frequent ICU admission, but no significant differences in readmittance or mortality rates within 180 days compared to controls. In the adjusted effects model, the need for supplementary oxygen on the 21st day after symptom onset, the presence of Ordinal Scale for Clinical Improvement (OSCI) = 4, when compared to OSCI ≤ 3, and higher C-reactive protein on admission, were significantly associated with higher odds for OP. No other differences were identified between OP and controls after adjusting for other factors. The use of remdesivir or dexamethasone did not impact the diagnosis of OP. Only 38% of OP patients required treatment with high-dose corticosteroids.In conclusion, SARS-CoV-2-induced OP may be more frequent than previously thought, especially among hospitalised patients and patients with a more severe disease, particularly those who fail to improve after the second week of disease or who present higher inflammatory markers on admission. It increases the length of stay, but not all patients require specific treatment and OP may improve despite the absence of high-dose corticosteroid treatment.

Virtual Bronchoscopy Planner and Radial-EBUS Guided Biopsy for Organizing Pneumonia Diagnosis.

Background: The diagnosis of organizing pneumonia (OP) often requires histological confirmation. The aim of this retrospective study was to evaluate the diagnostic yield and complication rate of radial endobronchial ultrasound (r-EBUS) for OP. Methods: All patients who had r-EBUS as a first diagnostic procedure for a peripheral pulmonary lesion at Rouen University Hospital, France, between April 2008 and December 2020 were included. Cases without a final diagnosis of OP or follow-up were excluded. Patients, lesions, and r-EBUS characteristics were retrospectively analyzed. Results: 2735 r-EBUS procedures were performed, and 33 cases with final OP could be analyzed. Procedures were performed under local anesthesia in 28/33 cases (85%). Among the 33 final OP cases, 17 were considered cryptogenic, and 16 secondary. The lesions were patchy alveolar opacities in 23 cases (70%), masses or pulmonary nodules in 8 cases (24%), and diffuse infiltrative opacities in 2 cases (6%). A bronchus sign on CT scan was found in all cases. In 22 cases (67%), a histopathological diagnosis was obtained from the r-EBUS samples. In 4 cases (12%), histopathological diagnosis was made by surgery, and in 7 cases (21%) the diagnosis was made based on clinical, radiological, and evolution features. An ultrasound image was found in 100% (22/22) of cases in the r-EBUS positive (r-EBUS+) group vs. 60% (6/10) in the r-EBUS negative (r-EBUS-) group, respectively (p < 0.002). The diagnostic yield of r-EBUS for OP was 67% and increased to 79% (22/28) when an ultrasound image was obtained. The median time between CT scan and r-EBUS procedure was 14 days (3–94): 11.5 days in the r-EBUS+ group and 22 days in the r-EBUS- group (p < 0.0001). No severe complications were reported. Conclusion: r-EBUS, when performed shortly after a CT scan showing a bronchus sign, is an efficient and safe technique for OP diagnosis.

Comparison of Chest CT Findings of COVID-19, Influenza, and Organizing Pneumonia: A Multireader Study

Background: Previous studies have compared CT findings of COVID-19 pneumonia with those of other infections; however, to our knowledge, no studies have included non-infectious organizing pneumonia (OP) as a comparison group. Objective: To compare chest CT features of COVID-19, influenza, and OP using a multireader design, and to assess radiologists' performance in distinguishing between these conditions. Methods: This retrospective study included 150 chest CT examinations in 150 patients (mean age 58±16 years) with diagnosis of COVID-19, influenza, or non-infectious OP (50 randomly selected abnormal CT examinations per diagnosis). Six thoracic radiologists independently assessed CT examinations for 14 individual CT findings and Radiologic Society of North America (RSNA) COVID-19 category and recorded a favored diagnosis. CT characteristics of the three diagnoses were compared using random effects models; readers' diagnostic performance was assessed. Results: COVID-19 pneumonia was significantly different (p<.05) from influenza pneumonia for seven of 14 chest CT findings, though different (p<.05) from OP for 4 of 14 findings [central or diffuse distribution in 10% and 7% of COVID-19 vs 20% and 21% of OP; unilateral distribution in 1% of COVID-19 vs 7% of OP; non-tree-in-bud nodules in 32% of COVID-19 vs 53% of OP; tree-in-bud nodules in 6% of COVID-19 vs 14% of OP]. A total of 70% of cases of COVID-19, 33% of influenza, and 47% of OP had an RSNA COVID-19 category of typical (p<.001). Mean percentage of correct favored diagnoses compared to actual diagnoses was 44% for COVID-19, 29% for influenza, and 39% for OP. Mean diagnostic accuracy of favored diagnoses was 70% for COVID-19 pneumonia and 68% for both influenza and OP. Conclusion: CT findings of COVID-19 substantially overlap with influenza and, to a greater extent, with OP. Radiologists' diagnostic accuracy was low in a study sample containing equal proportions of these three types of pneumonia. Clinical Impact: Recognized challenges in diagnosing COVID-19 by CT are furthered by our observed strong overlap between CT appearances of COVID-19 and OP. This challenge may be particularly evident in clinical settings with substantial proportions of patients with potential causes of OP such as ongoing cancer therapy or autoimmune conditions.

An unusual cause of "reverse batwing" sign.

An unusual cause of "reverse batwing" sign.

Clinico-etiological characteristics of organizing pneumonia

Introduction:Organizing pneumonia (OP) is an idiopathic interstitial pneumonia characterized radiologically by the patchy peripheral areas of ground-glass opacities and consolidation. It is commonly associated with a variety of conditions such as connective tissue diseases (CTD), drugs, infections, malignancy, radiation exposure, post-transplant, and other interstitial pneumonia. There are no specific clinical manifestations unless there is an underlying etiology. We present a series of such cases.Aims and Objectives:The aim of the study was to identify the clinical characteristics and etiological spectrum of patients manifesting radiologically with OP pattern.Materials and Methods:This was a retrospective analysis of clinico-radiological profile and etiological diagnosis of 23 patients, who had a radiological diagnosis of OP during the period of January 2017–September 2019.Results:Our patients presented with nonspecific symptoms of cough, fever, breathlessness, and occasionally with hemoptysis. The various etiologies identified were CTD (n = 4), infection (n = 2), drugs (n = 4), radiation (n = 1), chronic aspiration syndrome (n = 1), malignancy (n = 2), hypersensitivity pneumonitis (n = 1), and chronic heart failure (n = 2), and in majority (n = 7), no underlying etiology was evident and were labeled as cryptogenic organizing pneumonia.Conclusion:OP is an underdiagnosed entity and is associated with numerous diseases varying from pulmonary tuberculosis to malignancy. Identification of the underlying disease process is of paramount importance as it enables the treating physician to implement necessary therapeutic interventions.

Organizing pneumonia as a presentation of connective tissue disorders

Organizing pneumonia (OP) is a clinical, radiological, and histological entity that is classified under the group of interstitial lung diseases. The diagnosis of OP is based on a characteristic histological pattern in the presence of certain clinical and radiological features. We present four cases of OP who presented with respiratory complaints of several weeks duration. Skin lesions typical of underlying connective tissue disorders were observed in three patients, and these were confirmed on biopsy. The diagnosis of OP was confirmed with the computed tomography scan thorax of all cases and additionally on histopathology of pulmonary lesions in two cases. All of these patients responded well to steroids, but one patient died due to respiratory failure.

Ceritinib-Induced Organizing Pneumonia in Lung Cancer: A Retrospective Analysis.

Ceritinib is a potent selective ALK inhibitor with a manageable safety profile. In anecdotal reports, ceritinib was associated with organizing pneumonia (OP), which could be confused with disease progression. We aimed to delineate the characteristics of OP that occurs during treatment with ceritinib, and evaluate its clinical implications. We retrospectively analyzed 44 lung cancer patients whose tumors harbored ALK or ROS1 fusions and who had received ceritinib. OP diagnosis was based on radiographic and clinical features. Four OP cases were pathologically confirmed. Among 44 patients, 22 OP events occurred in 16 (36.4%) patients. The median time to the first event was 17.2weeks (range 6.7-68.7weeks). All events were grade 1 or 2. Radiographic features were categorized into four patterns: nodular (54.6%), consolidation (27.3%), parenchymal band (4.5%), and ground-glass opacity (GGO) (13.6%). OP improved in 20 events with drug interruption or corticosteroids. The median duration of OP was 11.3weeks (range 2-24weeks). Tumor response rate was 75% in OP-positive and 42.9% in OP-negative groups. The median progression-free survival was 16.7months [95% confidence interval (CI) 10.1-not applicable (NA)] in OP-positive and 5.4months (95% CI 3.6-8.4) in OP-negative patients (P = 0.004). The median overall survival was 46.2months (95% CI 38.1-NA) in OP-positive and 10.5months (95% CI 6.2-18.9) in OP-negative patients (P < 0.001). OP occurs frequently during ceritinib treatment and must be distinguished from disease progression. OP could be reversible without fatal complications and its occurrence is associated with better survival outcomes.

RP EBUS as a guide for transbronchial pulmonary biopsy in the diagnosis of organizing pneumonia.

Diffuse parenchymal lung diseases (DPLDs) include a wide variety of manifestations characterized by different degrees of inflammation and fibrosis with various patterns of secondary lobule alterations, such that the diagnosis often requires histopathological confirmation in addition to clinical and radiological data. Radial probe endobronchial ultrasonography (RP EBUS) can be used as a guide for transbronchial pulmonary biopsy (TBPB) to obtain tissue samples, and thus can be a useful tool in the diagnostic management of peripheral pulmonary lesions. Organizing pneumonia (OP) is a particular type of DPLD characterized by lung inflammation and scarring that obstruct the small airways and air sacs of the lung. In this study, we describe how and when RP EBUS can be used to guide TBPB and significantly help in the diagnosis of OP.

Organizing pneumonia revisited: insights and uncertainties from a series of 67 patients.

Background: Organizing pneumonia (OP) is classified as an acute/subacute pneumonia according to the American Thoracic Society/European Respiratory Society statement (2013 update). Although its clinical presentation, radiologic and histologic features are well established, data on the relevance of potential causes, corticosteroid doses and length, or management of relapses are based on heterogeneous series of patients. Objectives: The aims of this study were to describe clinical presentation, diagnosis and treatment of OP, explore potential causes, discuss strategies for managing relapses, and analyze prognostic factors. We also discuss our findings in relation to relevant data in the literature. Methods: We performed a cross-sectional study of all patients diagnosed with OP at a tertiary referral center in northern Portugal between 2008 and 2015. Results: Sixty-seven patients were diagnosed with OP over the 7-year study period. Dyspnea and cough were the most common presenting symptoms and approximately 30% of patients were hospitalized at the time of diagnosis. Approximately half of the patients were receiving drugs described as potential causes of OP. Microorganisms were isolated in approximately one-third of patients. Other potential causes identified were hematologic disorders, neoplasms, connective tissue diseases, myelodysplastic syndromes, immunodeficiencies, radiotherapy, and bird exposure. Cryptogenic OP was diagnosed in just 16 patients (23.8%). Corticosteroids were the most common treatment and 11 patients (16.4%) experienced relapse. Conclusions: The findings for this series of patients confirm the extreme variability of the contexts in which OP can occur and suggest that rather than a distinct, homogeneous clinicopathologic entity, OP is a non-specific reaction whose outcomes are dependent on the cause. (Sarcoidosis Vasc Diffuse Lung Dis 2018; 35: 129-138).

18 F-FDG uptake in focal organising pneumonia mimicking bronchial carcinoma.

Organising pneumonia (OP) is not a well-known cause of increased 18 F-FDG uptake, and the relationship of the increased 18 F-FDG uptake to clinical parameters has not been clearly identified. This study aims to assess the role of positron emission tomography-computed tomography (PET-CT) for the diagnosis of focal organised pneumonia that may mimic malignity because of mass-like lesions on the radiological images it causes. Among 40 patients of whom histopathological exams were consistent with OP, medical records of 14 focal OP patients diagnosed with surgical biopsy were evaluated retrospectively. There were 10 male (71.4%) and 4 female (28.6%) patients. The mean age at the time of diagnosis was 57.2 ± 11.7 years, ranging from 38 to 85 years. Nine subjects (64.3%) were smokers. Eleven patients (78.5%) had symptoms, the remaining 3 patients (21.5%) were asymptomatic. Three patients (21.3%) had a history of malignancy. Focal lung lesion was initially detected by chest radiography in 10 patients (71.4%) and by computed tomography (CT) scan in all patients. CT scan showed a single lesion in 12 (85.7%) patients. The lesions were located in the right lung of the half of patients (50%) and in the left lung of the other half. The median diameter of the lesions was 3.4 cm (range, 1.8-6.0 cm). PET with 18 F-FDG was performed in all patients, and hypermetabolic activity of the focal lung lesion was demonstrated in all cases. The median values of maximum standardized uptake value was 3.5 ± 2.7 (min 2.1-max 13.1). Focal OP is a discrete form of OP that is associated with unifocal lesions on radiological images, and it can easily mimic lung cancer because of positivity on PET scans. There are no specific findings of PET scan for the diagnosis of OP.

Organising pneumonia can be the inaugural manifestation in connective tissue diseases, including Sjögren's syndrome

Connective tissue diseases are known to be one of the causes of organising pneumonia (OP). However, this association is rare and signs of OP usually occur in the context of an already diagnosed disease. We report three cases of OP preceding the articular symptoms of the underlying connective tissue disease by 3-6 months in two cases of rheumatoid arthritis and by 36 months in one patient with primary Sjögren's syndrome. The diagnosis of post-infectious OP had initially been suspected in the three cases and the patients had not been followed up further. The occurrence of OP preceding articular or any other extrapulmonary involvement of connective tissue disease had been reported in only four cases in the literature and, to our knowledge, no case preceding Sjögren's syndrome had ever been reported. These observations suggest that exhaustive investigations should be considered when OP is diagnosed, including antinuclear auto-antibodies and investigations for Sjögren's syndrome, even when there are no clinical signs suggesting an underlying connective tissue disease. These investigations should also be repeated during the course of the disease, especially in the case of OP continuing to progress under treatment and, of course, if signs of connective tissue disease appear.

Pneumonia organizativa – Experiência da consulta de um hospital central

Aimto characterise outpatients of a Portuguese central hospital diagnosed with organising pneumonia (OP) and compare results with current literature. Methodsmedical processes with diagnosis of OP were retrospectively studied as to demographics, aetiology, clinical and radiological features, average time until and date of diagnosis, laboratory and histological changes, treatment and relapse. Results – thirteen patients with a mean follow-up of 171.6 weeks (max 334 and min 28 weeks) were evaluated. Nine of these patients (70%) had cryptogenic OP (COP) while 30% had secondary OP (SOP), two with rheumatoid arthritis, one with dermatomyositis and another undergoing radiotherapy for breast cancer. Mean age was 55.6 (+-15.3 years), 92% female, 77% were non-smokers. Average time until diagnosis was 77.2 weeks (min 3 and max 432 weeks). Symptoms at presentation were tiredness (92%), cough (85%), fever (65%), shortness of breath (54%), thoracic pain (23%) and weight loss (23%). At the time of diagnosis, the mean erythrocyte sedimentation rate was 70mm (max 170mm and min 16mm). C-reactive protein level was increased in eight patients. Significant leucocytosis was absent. Chest X-ray and chest CT scan showed bilateral distribution in 12 patients (92%). Consolidation with an air bronchogram was present in 12 patients and in four (31%), consolidation was migratory. Four patients (30%) underwent transbronchial pulmonary biopsy, all uncharacteristic and eight patients surgical pulmonary biopsy, four showed histological confirmation of SOP. Corticosteroids were started in 11 patients and average treatment was 61.6 weeks (16–288 weeks). 15% (2/13) had spontaneous resolution. Four patients (31%) relapsed, one of them five times. Two patients are dependent on a low dose of corticosteroids, one due to underlying disease and another due to multiple relapses. Therapy of relapse was corticosteroids alone in minimum effective dosage or associated to azathioprine or ciclosporin. Discussion and conclusionsuch a high incidence in females (92%) may be explained by the limited sample of patients. In 70% of the patients diagnosis were established by clinical and radiology criteria. Mean time to diagnosis was very variable which suggests that in some cases the disease was not diagnosed and treated as another interstitial lung disease or as recurrent pneumonia. Most patients (53.8%) had a favourable clinical course after treatment with corticosteroids with a very low number of relapses (30.8%), much lower than described by other authors (60%). Only in experienced centres should the diagnosis of OP established by clinical and radiological criteria.

Pneumonia organizativa – Experiência da consulta de um hospital central

Aim: to characterise outpatients of a Portuguese central hospital diagnosed with organising pneumonia (OP) and compare results with current literature. Methods: medical processes with diagnosis of OP were retrospectively studied as to demographics, aetiology, clinical and radiological features, average time until and date of diagnosis, laboratory and histological changes, treatment and relapse. Results – thirteen patients with a mean follow-up of 171.6weeks (max 334 and min 28 weeks) were evaluated. Nine of these patients (70%) had cryptogenic OP (COP) while 30% had secondary OP (SOP), two with rheumatoid arthritis, one with dermatomyositis and another undergoing radiotherapy for breast cancer. Mean age was 55.6 (+-15.3years), 92% female, 77% were non-smokers. Average time until diagnosis was 77.2weeks (min 3 and max 432 weeks). Symptoms at presentation were tiredness (92%), cough (85%), fever (65%), shortness of breath (54%), thoracic pain (23%) and weight loss (23%). At the time of diagnosis, the mean erythrocyte sedimentation rate was 70mm (max 170mm and min 16mm). C-reactive protein level was increased in eight patients. Significant leucocytosis was absent. Chest X-ray and chest CT scan showed bilateral distribution in 12 patients (92%). Consolidation with an air bronchogram was present in 12 patients and in four (31%), consolidation was migratory. Four patients (30%) underwent transbronchial pulmonary biopsy, all uncharacteristic and eight patients surgical pulmonary biopsy, four showed histological confirmation of SOP. Corticosteroids were started in 11 patients and average treatment was 61.6weeks (16-288 weeks). 15% (2/13) had spontaneous resolution. Four patients (31%) relapsed, one of them five times. Two patients are dependent on a low dose of corticosteroids, one due to underlying disease and another due to multiple relapses. Therapy of relapse was corticosteroids alone in minimum effective dosage or associated to azathioprine or ciclosporin. Discussion and conclusion: such a high incidence in females (92%) may be explained by the limited sample of patients. In 70% of the patients diagnosis were established by clinical and radiology criteria. Mean time to diagnosis was very variable which suggests that in some cases the disease was not diagnosed and treated as another interstitial lung disease or as recurrent pneumonia. Most patients (53.8%) had a favourable clinical course after treatment with corticosteroids with a very low number of relapses (30.8%), much lower than described by other authors (60%). Only in experienced centres should the diagnosis of OP established by clinical and radiological criteria.Rev Port Pneumol 2010; XVI (3): 369-389

Organizing Pneumonia

Organizing pneumonia (OP) is a histologic term characterized by patchy filling of alveoli and bronchioles by loose plugs of connective tissue. OP may be an incidental finding in lung biopsy specimens or may be found nearby areas of lung involved by other diseases. On other occasions, OP may be the primary cause for pulmonary dysfunction and/or pulmonary symptoms. OP can be either idiopathic (cryptogenic organizing pneumonia, COP) or secondary to underlying disease (secondary organizing pneumonia, SOP). COP typically presents with a prodrome of symptoms of a respiratory illness followed by the insidious onset of dyspnea weeks to months later. The radiological findings typically reveal peripheral consolidation, although ground glass infiltrates or solitary nodules may be seen. The definitive diagnosis of OP requires histology. Open lung biopsy or video assisted thoracoscopy is usually required to obtain specimens large enough for the diagnosis to be made. In some cases, transbronchial biopsy specimens may be adequate for the diagnosis. The treatment of choice for OP includes corticosteroids plus treatment of the underlying disease in cases of SOP. Relapses occur frequently, usually when treatment is withdrawn or tapered. The prognosis is good in most of the cases of COP, whereas in SOP it is dependent on the underlying cause.

Organizing pneumonia in patients with hematologic malignancies: A steroid-responsive lesion

Organizing pneumonia (OP) is a distinct histopathologic lesion that occurs in a variety of clinical contexts. There have been occasional reports of OP occurring in patients with hematologic malignancies. To examine the association of OP with hematologic malignancies and to assess the clinical course of affected patients. A retrospective review of our institutional experience of unexplained OP developing in patients with hematologic malignancies. Tertiary care, referral medical center. We identified 6 patients with a verified histopathologic diagnosis of OP and antecedent or concomitant diagnosis of a hematologic malignancy from the Mayo Clinic database (1995-2003). Clinical, radiologic, and outcome data were abstracted from records. Underlying hematologic disorders included lymphoma (2), acute leukemia (2), cutaneous T-cell lymphoma (1), and myelodysplastic syndrome (1). OP was diagnosed by surgical lung biopsy in 4 and bronchoscopic biopsy in 2. Four of the 6 patients had previously been exposed to chemotherapeutic agents, two had not. Three of the 6 patients had bone marrow transplantation prior to development of OP. Five patients were treated with prednisone and all experienced symptomatic improvement with documented radiologic resolution in 4. One patient experienced symptomatic and radiologic resolution with observation alone. Three patients ultimately died from complications of their underlying hematologic disorder and 1 patient died of unknown causes. Two patients were alive without respiratory complaints more than 1 year after lung biopsy. OP occurs in patients with underlying hematologic malignancies who may or may not have been treated with chemotherapy and responds favorably to corticosteroid therapy.