Internal Medicine

0521779407-B02 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 20:52

254 Bronchiolitis

■Bronchiolitis obliterans:

➣After inhalation of toxic fumes

➣After respiratory infections

➣Associated with connective tissue disorders (rheumatoid arthri-

tis, SLE, polymyositis, dermatomyositis)

➣After bone marrow transplantation: occurs in 10% of patients

with chronic graft-vs-host disease; preceded 2–3 mo after trans-

plantation by mucositis, esophagitis, skin rash

➣After lung or heart-lung transplantation: occurs in 30–50%

of lung transplant recipients; probably reflects chronic rejec-

tion

■Bronchiolitis obliterans with organizing pneumonia (BOOP):

➣Usually follows flu-like illness

➣Often thought to be slowly resolving pneumonia

■Respiratory bronchiolitis: smokers and patients with mineral dust

exposure

■Panbronchiolitis:

■Most cases in Japan; also non-Japanese Asians and caucasians

■Predominantly males, nonsmokers

■Associated with chronic sinusitis

Signs & Symptoms

■Despite widespread involvement of small bronchi and bronchioles,

symptoms may occur late

■Gradual onset of dyspnea and nonproductive cough

■Fever may be present with acute bronchiolitis

■Physical exam typically normal

■Wheezing uncommon; may be diffuse or localized

■Crackles or “Velcro” rales in 68% of patients with BOOP

■Rales common with respiratory bronchiolitis

tests

Laboratory

■Routine blood tests: usually normal

Imaging

■CXR, CT:

➣Variable pattern

➣Miliary or diffuse nodular; reticulonodular; normal

➣Hyperinflation or air trapping may be present