1. Nonspecificity of Immunohistochemistry for Mycobacteria Species Using a Rabbit Polyclonal Antibody.
- Author
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Kelley JT, Kroll-Wheeler L, Hrycaj S, Chan MP, Cheng J, and Lamps LW
- Subjects
- Rabbits, Animals, Humans, Mycobacterium Infections diagnosis, Mycobacterium Infections immunology, Mycobacterium Infections microbiology, Female, Male, Middle Aged, Mycobacterium immunology, Mycobacterium isolation & purification, Adult, Aged, Antibodies, Bacterial immunology, Antibodies, Bacterial analysis, Sensitivity and Specificity, Mycobacterium tuberculosis immunology, Mycobacterium tuberculosis isolation & purification, Nontuberculous Mycobacteria immunology, Nontuberculous Mycobacteria isolation & purification, Immunohistochemistry methods, Cross Reactions
- Abstract
Context.—: Recent publications have featured immunohistochemistry (IHC) as a sensitive tool for detecting Mycobacterium tuberculosis and nontuberculous mycobacteria, but performance is limited to cases suspected to have mycobacterial infection., Objective.—: To examine cross-reactivity of a polyclonal antimycobacterial antibody with various types of pathogens, tissues, and inflammatory patterns., Design.—: Surgical pathology files during a period of 6 years were searched, and 40 cases representing a variety of pathogens, tissue types, and inflammatory responses were retrieved. Cases were stained with a rabbit polyclonal antimycobacterial antibody (Biocare Medical, Pacheco, California). The cases and associated histochemical stains, culture, and molecular results were reviewed by 3 pathologists., Results.—: All 8 cases of mycobacterial infection previously diagnosed by other methods were positive for mycobacteria by IHC. In addition, multiple bacterial and fungal organisms and 1 case of Leishmania amastigotes were also immunoreactive with the mycobacterial IHC., Conclusions.—: Although highly sensitive for mycobacteria, the polyclonal antibody shows significant cross-reactivity with other organisms. This is a sensitive but nonspecific stain that can be used as an alternative confirmation method for mycobacteria, but attention should be paid to inflammatory reaction and organism morphology when IHC is positive to avoid misdiagnosis., Competing Interests: The authors have no relevant financial interest in the products or companies described in this article., (© 2024 College of American Pathologists.)
- Published
- 2024
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