Acute Hypersensitivity Pneumonitis Associated With a High Ki-67 Proliferative Index

Edward Nabrinsky; Amanda Kamar; Dereen Mohammed Saeed; Michael Pins; Arvey Stone

doi:10.7759/cureus.7905

Acute Hypersensitivity Pneumonitis Associated With a High Ki-67 Proliferative Index

Cureus. 2020 Apr 30;12(4):e7905. doi: 10.7759/cureus.7905.

Authors

Edward Nabrinsky¹, Amanda Kamar¹, Dereen Mohammed Saeed², Michael Pins³, Arvey Stone⁴

Affiliations

¹ Internal Medicine, Advocate Lutheran General Hospital, Park Ridge, USA.
² Pathology, University of Illinois, Chicago, USA.
³ Pathology, Advocate Lutheran General Hospital, Park Ridge, USA.
⁴ Pulmonary and Critical Care Medicine, Advocate Lutheran General Hospital, Park Ridge, USA.

Abstract

Hypersensitivity pneumonitis (HSP) is an interstitial lung disease caused by exposure to a large range of environmental antigens. Inhaling aerosolized particles leads to a heightened immune response. HSP comes in acute, subacute, or chronic forms, all with their own potential clinical and radiographic findings. Mycobacterium avium complex (MAC) is the most common nontuberculous mycobacteria and is known to cause HSP with certain exposures. However, although certain histologic findings can be seen with HSP, a high ki-67 proliferation index is unusual and more commonly associated with malignancy. In this report, we discuss a case of MAC that had acute HSP associated with a high ki-67 proliferative index.

Keywords: hsp; hypersensitivity pneumonitis; immunohistochemistry; ki-67; mac; mycobacterium; mycobacterium avium complex; proliferation.

Publication types

Case Reports