Non-Infectious Granulomatous Lung Disease: Imaging Findings with Pathologic Correlation

Abstract

Non-infectious granulomatous lung disease represents a diverse group of disorders characterized by pulmonary opacities associated with granulomatous inflammation, a relatively nonspecific finding commonly encountered by pathologists. Some lesions may present a diagnostic challenge because of nonspecific imaging features; however, recognition of the various imaging manifestations of these disorders in conjunction with patients' clinical history, such as age, symptom onset and duration, immune status, and presence of asthma or cutaneous lesions, is imperative for narrowing the differential diagnosis and determining appropriate management of this rare group of disorders. In this pictorial review, we describe the pathologic findings of various non-infectious granulomatous lung diseases as well as the radiologic features and high-resolution computed tomography imaging features.

Necrotizing sarcoid granulomatosis simulating pulmonary malignancy

“…[ 9 , 12 , 13 ] Therefore, the term “sarcoidosis with NSG pattern” is being used instead of NSG to reflect the clinical entity of nodular sarcoidosis. [ 4 , 7 , 8 ]…”

“…Recently, it is accepted as a more convincing idea that NSG is a variant of sarcoidosis with extensive infarct-like necrosis [9,12,13] . Therefore, the term “sarcoidosis with NSG pattern” is being used instead of NSG to reflect the clinical entity of nodular sarcoidosis [4,7,8] …”

“…[9,12,13] Therefore, the term "sarcoidosis with NSG pattern" is being used instead of NSG to reflect the clinical entity of nodular sarcoidosis. [4,7,8] Sarcoidosis with NSG pattern can be easily misdiagnosed as pulmonary malignancy or other pulmonary granulomatous diseases due to their similar radiologic findings and nonspecific clinical presentation. Sarcoidosis with NSG pattern has been reported in a wide range of age groups from 8 to 68 years, with a median age of 42 years.…”

“…[ 6 ] NSG is no longer a term for a disease entity, but a pathologic finding. It is being replaced by “sarcoidosis with NSG pattern.” [ 4 , 7 , 8 ] Usual clinical manifestations of sarcoidosis with NSG pattern are nonspecific. On imaging evaluation, sarcoid-like granuloma can be presented as solitary or multiple pulmonary nodules or masses similar to other granulomatous diseases.…”

Noninfectious Granulomatous Lung Disease: Radiological Findings and Differential Diagnosis

“…While each feature on its own can be nonspecific, the most common radiographic pattern is that of bronchopneumonia with scattered air-space opacities, manifesting as diffuse, small (1-3 mm) nodular areas of increased opacity representing the bronchiolar distribution of the aspirated material (Figure 7B) [67].…”