Pocket Medicine: The Massachusetts General Hospital Handbook of Internal Medicine (29 page)

•
Amiodarone
(~10%; dose & duration depend.): chronic interstitial pneumonia ↔ ARDS; bx → vacuolized Mf w/ lamellar inclusions on EM; Rx: d/c amio, give steroids • Other drugs: nitrofurantoin, sulfonamides, thiazides, INH, hydralazine, gold • Chemo: bleomycin (triggered by hyperoxia), busulfan, cyclophosphamide, MTX,
etc.

• XRT: COP/BOOP w/ sharply linear, nonanatomic boundaries; DAH

Idiopathic interstitial pneumonias (IIPs)
(
AJRCCM
2005;172:268)

• Definition:
ILD of unknown cause
; dx by radiographic, histologic and clinical features

UIP, usual interstitial PNA (IP); IPF, idiopathic pulm fibrosis (
Lancet
2011;378:1949); NSIP, nonspecific IP; COP, cryptogenic organizing PNA; BOOP, bronchiolitis obliterans w/ organizing PNA; AIP, acute IP (Hamman-Rich syndrome); DIP, desquamative IP; RB-ILD, resp bronchiolitis-assoc ILD.

• Rx for UIP/IPF: ?? NAC (
NEJM
2005;353:2229); pred + AZA harmful (
NEJM
2012;366:1968)

Experimental: tyrosine kinase inhib (
NEJM
2011;365:1079); pirfenidone (
Lancet
2011;377:1760; not avail in U.S.); ? sildenafil (
NEJM
2010;363:621); thalidomide for cough (
Annals
2012;157:398)

• Steroids for other IIPs: NSIP (esp. cellular type) and COP (
AJRCCM
2000;162:571); ? benefit for AIP and DIP/RB-ILD (for which Pts should stop smoking)
Environmental & occupational exposures
(
NEJM
2000;342:406;
Lancet
2012;379:2008)

•
Pneumoconioses
(inorganic dusts)

Coal worker’s: upper lobe coal macules; may progress to massive fibrosis

Silicosis: upper lobe opacities ± eggshell calcification of lymph nodes; ↑ risk of TB

Asbestosis: lower lobe fibrosis, calcified pleural plaques, DOE, dry cough, rales on exam. Asbestos exposure also → pleural plaques, benign pleural effusion, diffuse pleural thickening, rounded atelectasis, mesothelioma, lung Ca (esp. in smokers).

Berylliosis: multisystemic granulomatous disease that mimics sarcoidosis

•
Hypersensitivity pneumonitides
(organic dusts): loose, noncaseating
granulomas

Antigens: farmer’s lung (spores of thermophilic actinomyces); pigeon fancier’s lung (proteins from feathers and excreta of birds); humidifier lung (thermophilic bacteria)

Collagen vascular diseases
(
NEJM
2006;355:2655)

•
Rheumatologic disease

Scleroderma: fibrosis in
67%; PHT seen in
10% of CREST Pts

PM-DM: ILD & weakness of respiratory muscles; MCTD: PHT & fibrosis

SLE & RA: pleuritis and pleural effusions more often than ILD; SLE can cause DAH

•
Vasculitis
(can p/w
DAH
)

Wegener’s granulomatosis (
c-ANCA) w/ necrotizing granulomas

Churg-Strauss syndrome (
c-or p-ANCA) w/ eosinophilia & necrotizing granulomas

Microscopic polyangiitis (
p-ANCA) w/o granulomas

•
Goodpasture’s syndrome
= DAH + RPGN; typically in smokers;
anti-GBM in 90%

•
Lymphangioleiomyomatosis
(LAM): cystic, ↑ in
, Rx w/ sirolimus (
NEJM
2011;364:1595)
Pulmonary infiltrates w/ eosinophilia (PIE)
=
eos on BAL ± periph. blood

•
Allergic bronchopulmonary aspergillosis
(
ABPA
): allergic reaction to
Aspergillus

Criteria: asthma, pulm infiltrates (transient or fixed), skin rxn & serum precipitins to
Aspergillus
, ↑ IgE to
Aspergillus
& total (>1000), ↑ eos, central bronchiectasis

Rx: steroids ± itraconazole for refractory cases (
NEJM
2000;342:756)

• Löffler’s syndrome: parasites/drugs → transient pulm infilt + cough, fever, dyspnea, eos • Acute eosinophilic PNA (AEP): acute hypox febrile illness; Rx: steroids, tobacco cessation • Chronic eosinophilic pneumonia (CEP): “photonegative” of CHF, typically in women • Other: Churg-Strauss syndrome; hypereosinophilic syndrome
Miscellaneous

• Pulm alveolar proteinosis (PAP): accum of surfactant-like phospholipids;
smokers; white & gummy sputum; BAL milky fluid (
NEJM
2003;349:2527); Rx w/ lung lavage & GMCSF

• Langerhans cell granulomatosis (LCG): young
smokers; apical cysts; PTX (25%) • Lymphocytic interstitial PNA: polyclonal B-cell infiltration (? lymphoma); Rx: steroids

PLEURAL EFFUSION

Pathophysiology

•
Systemic factors
(eg, ↑ PCWP, ↓ oncotic pressure) →
transudative
effusion •
Local factors
(ie, Δ pleural surface permeability) →
exudative
effusion
Transudates

•
Congestive heart failure
(
40%
): 80% bilateral, ± cardiomegaly on CXR occasionally exudative (esp. after aggressive diuresis or if chronic), but ~75% of exudative effusions in CHF Pts found to have non-CHF cause (
Chest
2002;122:1518) •
Constrictive pericarditis
(knock on exam, calcification or thickening on imaging) •
Cirrhosis
(“hepatic hydrothorax”): diaphragmatic defect w/ passage of ascitic fluid often right-sided (
²
/
₃
) & massive (even w/o marked ascites) • Nephrotic syndrome: usually small, bilateral, asymptomatic (r/o PE b/c hypercoag) • Other: PE (usually exudate), malignancy (lymphatic obstruction), myxedema, CAPD