000 Nonspecific Interstitial Pneumonia, NSIP Introduction

In a Nutshell Buzz (NB)
Position of Disease
Lower Lobe distribution – apico-basilar gradient
Ashley Davidoff MD TheCommonvein.net lungs-0771

 

Position and Nature of NSIP
Broncho vascular and inter- alveolar interstitial fibrosis dominantly in the lower lobes but affecting the middle and upper lobes to lesser extent resulting in bronchiectasis and reticulations.  The overall increase in density results in ground glass changes 
Ashley Davidoff MD TheCommonvein.net lungs-0738 NSIP
Imaging Manifestations of  NSIP
Broncho vascular distribution associated with peripheral sparing, ground glass changes, reticulations, and volume loss, dominantly in the lower lobes but to some extent in the middle lobe and upper lobes
Ashley Davidoff MD TheCommonvein.net lungs-0771b
Imaging Manifestations of  NSIP
Broncho vascular distribution associated with peripheral sparing, ground glass changes, reticulations, and volume loss, dominantly in the lower lobes but to some extent in the middle lobe and upper lobes
Ashley Davidoff MD TheCommonvein.net lungs-0771b

Fibrotic NSIP

Imaging Manifestations of  Fibrotic NSIP
Broncho vascular distribution associated with increased reticular changes, more prominent traction bronchiectasis, decreased lung volumes , and decreased lung volumes,  dominantly in the lower lobes but to some extent in the middle lobe and upper lobes.  Pulmonary hypertension becomes more common.
Ashley Davidoff MD TheCommonvein.net lungs-0771d

Starts Central and Spreads Outward Along the Bronchovascular bundle

peribronchovascular

symmetric

ground glass

reticulation

traction bronchiectasis

loss of volume

subpleural sparing 60-65%

confluent

reticular

consolidations

honeycomb rare

Interlobular septa
can be thickened.

Alternatively All the S’s

subpleura

sparing

symmeteric

ground glass

scleroderma sle and all the other s’s arthritis, vasculitis

 

basal

? Interlobular septa

 

In general not progressive

May get better on Rx

 

Size

thickening of bronchovascular bundles

Shape
Position

subpleural (subpleural sparing,  specific for NSIP but other causes eg small airway disease)

relatively symmetric

apico-basilar gradient

Character

ground glass

fine reticulation

reticular opacities and irregular linear opacities (sometimes – minor subpleural reticulation)

Associated Findings

volume loss

traction bronchiectasis

Classical Subpleural Sparing

SCLERODERMA NSIP
NSIP
CT scan through the chest shows relatively symmetrical and peripherally positioned ground glass infiltrates with a region of subpleural sparing (red arrowhead)
Courtesy Pathology Outlines
http://www.pathologyoutlines.com/

http://www.pathologyoutlines.com/

NSIP
CT scan through the lower lobes showing basilar ground glass opacification with peribronchial thickening and traction bronchiectasis
Courtesy pathology Outlines
http://www.pathologyoutlines.com/
NSIP
CT scan through the lower lobes showing basilar ground glass opacification, with fine reticulation
Courtesy pathology Outlines
http://www.pathologyoutlines.com/
NSIP
CT scan through the lower lobes showing basilar ground glass opacifictaion with peribronchial thickening and traction bronchiectasis
Courtesy pathology Outlines
http://www.pathologyoutlines.com/

 

 

  • NSIP
    CT scan through the lower lobes showing basilar ground glass opacifictaion with peribronchial thickening and traction bronchiectasis
    Courtesy pathology Outlines
    http://www.pathologyoutlines.com/

    TYPICAL FINDINGS IN NSIP
    Spatially homogeneous pattern of fibrosis seen in non specific interstitial pneumonia (NSIP) (trichrome stain X40)
    Courtesy Medscape eMedicine

    Methotrexate-induced NSIP in a 41-year-old woman with rheumatoid arthritis who presented with dyspnea and decreased diffusing capacity of the lungs for carbon monoxide (Dlco). (a) High-resolution CT scan shows
    scattered ground-glass attenuation and thickened inter- and intralobular lines (arrow). (b) Photomicrograph (original
    magnification, 400; hematoxylin-eosin stain) of a specimen from lung biopsy shows patchy interstitial fibrosis, expansion of the interstitium by chronic inflammatory infiltrates, and reactive hyperplastic type II pneumonocytes (arrow), findings consistent with NSIP induced by the pulmonary toxic effects of methotrexate.
    Diffuse mucinous bronchioloalveolar carcinoma in a 78-year-old man. (a) High-resolution CT scan
    shows a bilateral crazy-paving pattern and centrilobular nodules. (b) Photomicrograph (original magnification,
    400; hematoxylin-eosin stain) of a specimen from open lung biopsy shows replacement of the alveolar epithelium
    by epithelial neoplastic cells with abundant intracytoplasmic mucin (arrows).
    Rossi, S.E et al “Crazy-Paving” Pattern at Thin-Section CT of the Lungs: RadiologicPathologic Overview Radiographics  Volume 23 – Number 6,  2003

  • Cellular NSIP and Fibrotic NSIP

  • NSIP can be divided into two subtypes based on the predominant histological pattern seen on lung biopsy: cellular NSIP and fibrotic NSIP.
    • In Cellular NSIP, the lung tissue is
    • relatively little fibrosis. In contrast,
      • CT
        •  patchy or diffuse ground-glass opacities
        • may be associated with a reticular pattern and
        • traction bronchiectasis
        • more pronounced in the
          • peripheral regions of the lungs, and may be
          • subpleural or
          • peribronchovascular
            • may also be consolidation in some areas of the lung.
    • In Fibrotic NSIP
      • presence of fibrosis or
      • scarring within the lung tissue.
      • worse prognosis c
      • more severe respiratory symptoms,
      • lower lung function, and a
      • greater likelihood of developing pulmonary hypertension.
        • CT
          • shows more pronounced and
          • diffuse reticular opacities and
          • traction bronchiectasis, with
          • less ground-glass opacities
          • fibrotic changes may be
            • more extensive and involve
            • larger areas of the lung tissue.
          • may also be
            • honeycombing in advanced cases.
  • The fibrotic form of nonspecific interstitial pneumonia (NSIP) is a
    subtype characterized by a predominant pattern of lung fibrosis,
    with varying degrees of inflammation. Unlike the cellular form, the
    fibrotic form involves more extensive scarring of the lung
    interstitium, leading to thickening and stiffening of the lung tissue.
    This subtype is often associated with autoimmune diseases (like
    systemic sclerosis, rheumatoid arthritis, or dermatomyositis) and
    can also occur as an idiopathic condition. Diagnosis is based on
    high-resolution CT (HRCT) scans, which often reveal reticular
    opacities, traction bronchiectasis, and subpleural sparing, but
    typically lack honeycombing. A lung biopsy may be necessary to
    confirm the diagnosis. The fibrotic form of NSIP generally has a less
    favorable prognosis than the cellular form, as the extent of fibrosis
    limits the reversibility of the condition, though some patients may
    still respond to immunosuppressive therapies.

Radiopedia

Primarily idiopathic but the morphological pattern can be seen in association with a number of conditions:

Pathology Outlines

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