400 likes | 1.35k Views
BOOP. BRONCHIOLITIS OBLITERANS ORGANIZING PNEUMONIA ( a review ) . BUHMC. THE BROOKDALE UNIVERSITY HOSPITAL & MEDICAL CENTER BROOKLYN, NEW YORK, NY, 11212 SIVAKUMAR PADMANABHAN, MD FELLOW, PULMONARY MEDICINE. BOOP--INTRODUCTION.
E N D
BOOP BRONCHIOLITIS OBLITERANS ORGANIZING PNEUMONIA ( a review )
BUHMC THE BROOKDALE UNIVERSITY HOSPITAL & MEDICAL CENTERBROOKLYN, NEW YORK, NY, 11212 SIVAKUMAR PADMANABHAN, MD FELLOW, PULMONARY MEDICINE
BOOP--INTRODUCTION • Bronchiolitis Obliterans - refers to a generic term of non-specific inflammatory reaction of small airways in response to exogenous/endogenous stimuli • Comprises two types - based on histopathology • Clinical features mimic pneumonia without response to antibacterial therapy
BOOP - INTRODUCTION • Once BOOP is documented - look for a precipitating factor • Rx: Steroids/Immunosuppressive agents • Prognosis: Excellent for idiopathic BOOP
Constrictive or Obliterative Bronchiolitis- Concentric Narrowing of Bronchioles with fibrous tissue --> airflow limitation Proliferative Bronchiolitis- Exuberant Granulation tissue and intraluminal plugs of connective tissue(Masson body) in respiratory bronchiole, alveolar duct and alveoli OB vs BOOP
BOOP- EPIDEMIOLOGY • First described in 1901 by Lange • 1985-- More cases reported by Epler et al • Age incidence: 4th- 7th decades • No gender predominance seen • Incidence: 6-7 per 100,000 admissions • Smoking is not a risk factor
SECONDARY BOOP IDIOPATHIC BOOP BOOP- Classification
SECONDARY BOOP • Connective tissue disorders - SLE, RA, Polymyositis - Dermatomyositis, Sjogren’s syndrome, MCTD, Ulcerative Colitis, Vasculitis • Inhaled/Systemic Toxins - gases, nicotine, cocaine, CO, nitrogen, chlorine • Drugs - Penicillamine, Amiodarone, Gold, Bleomycin, Mitomycin-c, Methotrexate, Sulfasalazine
SECONDARY BOOP • Interferon Rx for Hepatitis C - reported Chest 1994 Aug; 106 (2):612-3 Ogata k, Koga T, Yagawa K, Japan
SECONDARY BOOP • Infections: • Mycoplasma, HIV, HSV, CMV, Rubeola, Klebsiella, Hemophilus, Legionella, Grp B- Strep, Cryptococcus, Nocardia, PCP • Pediatric • RSV, Parainfluenza, Adenovirus, Mycoplasma
SECONDARY BOOP • Obstructive Pneumonitis • Hypersensitivity Pneumonitis • Aspiration Pneumonitis • Chronic Eosinophilic Pneumonia • Diffuse Alveolar Damage • Myelodysplastic Syndrome • Hematological malignancy
SECONDARY BOOP • Allograft transplant • Heart, Lung, Bone Marrow • 5-15% in those with GVHD • 1% of Allogenic transplant recepients without GVHD or in Autologous transplant recepients • IPF, ARDS
BOOP - CLINICAL FEATURES • SUBACUTE illness: • non-productive cough • exertional dyspnea - few weeks • Constitutional symptoms: • fever, malaise, weight loss • one- third have a preceding upper respiratory tract infection • MIMICS Community Acquired Pneumonia
BOOP- CLINICAL FEATURES • Physical exam : • Tachypnea, Crackles • Clubbing is rare • Rarely BOOP can mimic Bronchogenic CA by presenting as a solitary pulmonary nodule with cavity and hemoptysis • Unilateral BOOP has been described
BOOP- LAB TESTS • High ESR & CRP - secondary to inflammatory process • 1/3rd have a leukocytosis • Chest Xray: Patchy peripheral bilateral migratory alveolar infiltrates • 20-30% - reticular or nodular infiltrate • Pleural effusions in 30% due to secondary BOOP
BOOP- Imaging • CXR- can be normal in 4-10% • Cavitation & lymphadenopathy are absent • Focal consolidation is a marker for a good response to steroid therapy
BOOP- IMAGING • High Resolution CAT scan of Chest: patchy consolidation, ground glass opacity, nodularity with subpleural lower lobe predeliction. • Bronchial wall thickening and dilatation denote severe disease • Honey combing not seen in idiopathic BOOP
PFTs in BOOP • Restrictive Defect with Low Vital capacity • Low DLCo • Resting and exercise induced Hypoxemia • Pressure-Volume curve shifted down and right due to decreased lung compliance • Obstructive defect is not a feature unless patient is a smoker
BOOP- Bronchoscopy • BAL- High lymphocytes and Neutrophils • Foamy macrophages • Low CD4-CD8 ratio • Transbronchial Biopsy may miss representative lesions but may still be useful • Gold standard- Open lung or thoracoscopic lung biopsy for histopathology
BOOP-Pathogenesis • Accelerated host response to injury- • Bacterial or viral antigen; • Inhaled or noxious stimulus Lung injury Inflammatory cascade subsequent repair
BOOP-HISTOLOGY • Exuberant inflammation and fibrosis in terminal & respiratory bronchioles. • Terminal bronchioles plugged with granulation tissue, neutrophils, edema, fibrin, connective tissue, myoblasts, fibroblasts. • Extends to peribronchiolar region, alveolar duct and alveolar space - organizing pneumonia component
BOOP-HISTOLOGY • Cells-mononuclear, neutrophils, eosinophils, mutinucleate giant cells. • Lesions in peribronchiolar distribution seen on low power is a clue to diagnosis. • Preserved underlying alveolar architecture • Fibrosis usually does not occur • Stereotypic response to lung injury ie lesions are of same age
BOOP- DIFFERENTIAL DIAGNOSIS • Community Acquired Pneumonia • Drug Reactions, ARDS, • Chronic Eosinophilic Pneumonia, • Lymphoproliferative malignancy, • Bronchogenic ca (bronchoalveolar cell) • Histology may resemble usual intersitial pneumonitis or organising diffuse alveolar damage
BOOP VS OB • Obliterative Bronchiolitis due to RA, toxic fumes, bone marrow or lung transplant • CXR - may be normal • PFTs - obstructive or mixed defect • Pathology - concentric bronchiolar narrowing by intramural fibrosis without interstital involvement
BOOP vs OB • OB- Poor response to steroids • OB- Poor prognosis • OB- No spontaneous recovery
BOOP--Treatment • Spontaneous recovery occurs rarely • Antibiotic therapy for underlying infections • Withdrawal of offending toxin/ drug • Supportive therapy • Steroids for idiopathic BOOP and BOOP secondary to connective tissue disorders
BOOP-STEROID Rx • Prednisone- 0.5-1.0 mg/kg/day x 1-3 mos • Taper slowly over several months on individual basis • Duration of Rx 6- 12 months • Relapse may occur during steroid taper • Monitor by clinical, CXR and PFTs. • Response occurs in days to weeks
BOOP-- STEROID Rx • Idiopathic BOOP responds to steroids better than BOOP due to connective tissue disorders
BOOP-Prognosis • 65%- idiopathic BOOP cases have complete clinical, radiographic and physiologic resolution • 20%-Residual pulmonary fibrosis • 3-10%- mortality rate • Secondary BOOP has poor response to steroid Rx
BOOP- Rx • Immunosuppressive agents - cyclophosphamide, azathioprine for those who fail to respond to steroid Rx • Low dose erythromycin has an immunomodulatory effect
FULMINANT BOOP • Rapidly progressive to respiratory failure requiring mechanical ventilation (9 0f 10 patients in a series by Cohen & Colleagues) • Predisposed by Smoking, drugs, connective tissue disorders and environmental agents • Necropsy-septal inflammation, interstitial fibrosis & honeycombing
FULMINANT BOOP • Rx: High dose steroids and immunosuppressive agents • Course: Death or severe residual pulmonary fibrosis
Summary--BOOP • BOOP represents a nonspecific reaction pattern of lung to a wide variety of insults. • Clinical/Histologic correlation aids in correct assessment of diagnostic, therapeutic and prognostic significance
BOOP- References • Fishman’s Pulmonary Diseases & Disorders: vol 1, 3rd ed, ch. 54 p 825-847 • Comprehensive Respiratory Medicine by R Albert, S Spiro, J Jett, 9 48.4--48.6 • ACCP Pulmonary Board Review 1998-99 p.163-166 J P Lynch III ,MD, FCCP • MKSAP- Pulmonary & Critical Care , 2nd ed,ch.4.S B Fiel, J P Lynch III p 108-116 • BOOP associated with acute Mycoplasma infection Clin Inf Dis 1997 Dec, 25(6):1340-2,Llibre JM, Urban A, Garcia E, Carrasco MA, Murcia C • Low dose erythromycin for treatment of BOOP Kurume Med J, 1993; 40(2);65-7 Ichikawa Y, Ninomiya H, Katsuki M, Hotta M, Tanaka M, Oizumi K • A case of Unilateral BOOP, Nebr Med J,1996 May;81(5):149-51 Kanwar BA,Shehan CJ,Campbell JC, Dewan N, O’Donohue WJ Jr