Usual Interstitial Pneumonia
UIP

• The most common of the diffuse interstitial pneumonias

• Begins with diffuse damage to alveolar walls

• Necrosis of alveolar lining cells is followed by regeneration

• There is an abundance of polys in bronchial washings in contrast to lymphocytes found in sarcoid or hypersensitivity pneumonias

X-Ray

• Earliest manifestation consists of fine reticular pattern, particularly at the lung bases

• Becomes coarser as disease progresses and ends with honeycomb lung

• Progressive loss of volume is characteristic of either UIP or scleroderma

Clinically

• Symptoms include SOB, non-productive cough and fatigue

• Clubbing of the fingers is very common (85%)

• Cyanosis and pulmonary hypertension usually occur late in the disease

• “Velcro” rales on auscultation

• About 1/3 have +ANA titers and 1/3 have + Rheumatoid factors

Other chronic interstitial pneumonias

• BIP (Bronchiolitis obliterans and diffuse interstitial pneumonia)–favors upper lobes

• DIP (desquamative interstitial pneumonia)–second most common chronic interstitial pneumonia

• Heavy concentration of mononuclear cells rather than polys as in UIP

• Loss of type I alveolar epithelial cells and proliferation of type II cells

• Ground glass pattern in both lower lung fields

• LIP (lymphoid interstitial pneumonia) — like lymphoma

• No characteristic x-ray picture

• GIP (giant cell interstitial pneumonia) — characterized by multinucleated giant cells in the alveoli

• No characteristic x-ray picture