Kerala man's tongue turns 'black and hairy' after being put on a pureed diet

Elongated, black fibers that gave the appearance of a hairy surface was noticed on the patient's tongue. (Image: Medical Trust Hospital/JAMA)

A Kerala man’s tongue turned dark and hairy after he was put on a pureed diet following a stroke, according to a new report published in a medical journal.

The case, known medically as lingua villosa nigra, happened three months after the stroke left the patient’s left side paralysed. For three months, the man was fed only pureed and liquid food which led to the tongue’s discolouration and carpet-like hair growth. Black hairy tongue or BHT can be the result of a buildup of dead skin cells on the papillae of the tongue, which contains taste buds.

These papillae can easily be affected by bacteria, yeast, tobacco, food or other substances. Other possible causes of BHT include poor oral hygiene, excessive alcohol intake, or changes in the mouth after the uses of antibiotics.

The patient, who is in his 50s, was treated with proper oral cleaning measures and his condition was reversed in 20 days, doctors at the Medical Trust Hospital in Kochi documented in a journal.

“On examination, he did not have a fever and was conscious and oriented, with left-sided motor weakness. The dorsal aspect of his tongue showed a thick black coating that was yellowish toward the medial and proximal parts. Dermoscopy results showed thin, elongated, black fibers that gave the appearance of a hairy surface,” the report read after which doctors diagnosed the man with black hairy tongue (BHT).

The condition is common - an estimated 13 per cent of people develop black hairy tongue at some point in their life, although it is most common in adults over 40 years of age, according to the American Academy of Oral Medicine.

This doesn’t cause any pain or problem and typically does not require any specific treatment other than proper and regular oral hygiene and care.