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Pink spots of Hedley-Whyte in formaldehyde-fixed brains. The subject revisited
M A Mitchell1, S M Nakamura, J J Godyn
1Department of Pathology, Robert Wood Johnson Medical School, New Brunswick, NJ 08903-0019.
Abstract:
In an article published in 1985, Hedley-Whyte described "pink spots," which she observed in gross sections of human brains fixed in formaldehyde solution. Hedley-White found that the spots in question were associated with the presence of bacteria within central nervous system blood vessels. We have recently encountered three cases of Hedley-Whyte-type pink spots during routine postmortem brain examination. In two of these cases, the patient's clinical history included a bacterial infection, which could account for the deposition of bacteria within the central nervous system blood vessels. In the third case, the patient had no clinical history of bacterial infection, and had a negative postmortem blood culture. On microscopic examination, all three cases showed central nervous system intravascular presence of bacteria within the macroscopically recognized pink spots. To test the hypothesis that pink spots result from bacterial fermentation products, at the time of postmortem removal of brains (different from the brains mentioned above), we perfused blood vessels in three brains with 100% ethanol. Subsequent macroscopic examination after fixation in formaldehyde revealed discoloration similar to the Hedley-Whyte spots.
Insights
Pink spots in human brain tissue are linked to bacteria within blood vessels. This study confirms their presence and suggests fermentation products may cause the discoloration.
Area of Science:
- Neuropathology
- Microbiology
Background:
- Hedley-Whyte first described "pink spots" in human brain gross sections in 1985.
- These spots were associated with bacteria in central nervous system (CNS) blood vessels.
Observation:
- Three recent cases of Hedley-Whyte-type pink spots were observed during postmortem brain examinations.
- Two cases had a clinical history of bacterial infection, correlating with CNS intravascular bacteria.
- One case lacked a bacterial infection history, yet microscopic examination revealed CNS intravascular bacteria within the pink spots.
Findings:
- Microscopic examination confirmed the presence of bacteria within the CNS blood vessels in all three cases.
- Experimental perfusion of brain blood vessels with ethanol produced discoloration similar to Hedley-Whyte spots, supporting the hypothesis of fermentation products.
- This suggests bacterial fermentation products may be responsible for the characteristic pink discoloration.
Implications:
- The findings reinforce the association between CNS intravascular bacteria and Hedley-Whyte pink spots.
- This research provides a potential explanation for the observed postmortem brain discoloration, even in cases without a clear clinical history of infection.
- Understanding the cause of these spots aids in accurate neuropathological diagnosis and interpretation.
