ABSTRACT
Nonspecific interstitial pneumonia (NSIP) represents one histologic subtype of idiopathic
interstitial pneumonia (IIP). NSIP is typified by temporal homogeneity and less profusion
of fibroblastic foci than is seen with usual interstitial pneumonia (UIP), the most
common IIP. Clinically patients with NSIP present with similar symptoms (cough and
dyspnea) when compared to patients with UIP. The duration of these symptoms prior
to presentation is variable. The finding of fever may be more common in NSIP and clubbing
may be more common in UIP; however, both findings can be seen in either UIP or NSIP.
Physiological findings typically demonstrate a restrictive ventilatory defect with
decreased gas transfer; little difference exists between UIP and NSIP. High resolution
computed tomography (HRCT) scans are more likely to show honeycombing with UIP and
a ground-glass pattern with NSIP, however, either of these findings can be seen with
UIP or NSIP. The most striking differential feature between NSIP and UIP is the markedly
better prognosis for patients with NSIP, a finding that cannot be explained by baseline
differences in physiology or radiographic features. In this article we explore the
clinical, physiological, and radiographic features of NSIP. We also review available
information regarding response to therapy and prognosis.
KEYWORD
Idiopathic interstitial pneumonia - nonspecific interstitial pneumonia