A new medical case study in BMJ Case Reports tells a very unusual story involving a heart transplant, a vacation in North Carolina, bat poop, and a very sneaky fungal infection.
Doctors from the University of Arizona Health Sciences Center explain how a 70-year-old man visited the hospital in Tucson after suffering from an “altered mental status” and confusion for a number of days. A CT-scan highlighted a number of unusual blotches on the man’s brain, strongly suggesting there was some kind of growth.
Further tests indicated that the man might be suffering from a histoplasmosis fungal infection, better known as “cave disease" or "Ohio valley disease”. This fungus often thrives in decaying bird poop, bat guano, and soil found around the humid caves of the Ohio and Mississippi River valleys, as well as select parts of the Americas, Africa, Asia, and Australia.
However, there was just one problem: the man had remained in Arizona for many years, where there are next to no reported cases of the fungus. Furthermore, symptoms typically appear within just two weeks of inhaling the spores.
The fungal spores usually enter a person’s lungs and trigger a fever, cough, tiredness, and various other nasty flu-like symptoms. However, most people can fight off an infection relatively easily unless they have a suppressed immune system. Johnny Cash even sang about a nasty run-in with the fungus in the song Beans for Breakfast.
Some hard detective work by the doctors revealed what might be behind this odd set of circumstances. The man had a vacation in North Carolina, an area known to harbor the fungus, during the mid-1980s. In 1986, he had also undergone a heart transplant and was given long-term immunosuppressant drugs to make sure his body didn’t reject the transplanted organ. These drugs allowed the fungal spores to lay hidden in his body undetected by the immune system. It appears that the fungus had only just presented itself in his brain, 30 years after the initial infection.
The man was discharged from the hospital, given an antifungal medication to treat the infection, and later made a recovery. The doctors on the case say it's a reminder of how histoplasmosis can often play a fickle game by not always presenting itself where and when you think it should.