A man's voice grew hoarse for no obvious reason. It turns out, he had fungus in his throat.

close up of an older man holding his throat in discomfort, as if it's sore
Fungus in a man's throat caused his voice to become hoarse. (Image credit: vitapix via Getty Images)

Over the course of a year, a man's voice grew progressively more hoarse and his speech became shrill and grating, but he didn't know why. Upon examining the man, doctors discovered the reason: Fungus was growing in his throat.

According to the report of the man's case, published Thursday (Aug. 4) in the journal JAMA Otolaryngology–Head & Neck Surgery, the man appeared otherwise healthy when he went to a clinic in Pennsylvania that treats conditions of the head and neck. The man, in his 60s, reported that he'd developed "progressively worsening hoarseness" and shortness of breath over the past 12 months. His primary care physician had previously treated him with inhaled corticosteroids — a standard treatment for asthma — but his symptoms hadn't improved.

To examine the man's vocal folds and larynx, the hollow "voice box" that holds the vocal folds, doctors used a high-speed imaging technique called videostroboscopy. This exam revealed "severe" swelling in the tissue lining the patient's throat, and this swelling had caused the airway to narrow. The doctors also performed a biopsy on tissue from the man's larynx and confirmed that the tissue was swollen, irregular and "friable" to the touch, meaning it tore easily.

A close-up examination of the sampled tissue revealed patches of dead laryngeal cells surrounded by clusters of immune cells, hinting that the cells had died off due to intense inflammation in the throat. The examination also revealed budding yeast cells, which the immune cells had surrounded and begun to engulf.

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A diagnostic test identified the yeast as Blastomyces dermatitidis, a fungus that causes an infection called blastomycosis. 

B. dermatitidis grows in outdoor environments, typically in moist soil and decomposing wood and leaves, according to the Centers for Disease Control and Prevention (CDC). In the U.S., the species is especially prevalent in areas surrounding the Ohio and Mississippi River valleys, the Great Lakes and the St. Lawrence River. People can develop blastomycosis after breathing in B. dermatitidis spores suspended in the air, although most people exposed to the fungus don't become ill. 

Having a weakened immune system raises the risk of infection, and those who become sick typically develop symptoms between three weeks and three months after breathing in the fungal spores. Sometimes, the infection can spread to the lungs, skin, bones or central nervous system, meaning the brain and spinal cord, according to the CDC. 

In the man's case, the fungus grew only in his larynx, which is fairly unusual. "Laryngeal blastomycosis, first reported in 1918, is a rare extrapulmonary manifestation," his doctors noted in the case report.

Due to the significant obstruction of the man's airway, he underwent surgery to have a breathing tube placed in his windpipe and a feeding tube placed in his stomach. He received a long-term prescription for the antifungal drug itraconazole, and at a two-month follow-up appointment, his hoarseness had improved considerably and he had his feeding tube removed. 

At a five-month follow-up, videostroboscopy revealed that the swelling in the man's throat had gone down and that his vocal folds had regained some mobility. At this point, his breathing tube was also removed.

Originally published on Live Science. 

Nicoletta Lanese
Channel Editor, Health

Nicoletta Lanese is the health channel editor at Live Science and was previously a news editor and staff writer at the site. She holds a graduate certificate in science communication from UC Santa Cruz and degrees in neuroscience and dance from the University of Florida. Her work has appeared in The Scientist, Science News, the Mercury News, Mongabay and Stanford Medicine Magazine, among other outlets. Based in NYC, she also remains heavily involved in dance and performs in local choreographers' work.