Imipenem-cilastatin and Linezolid induced black hairy tongue and teeth used in an Extremely drug resistant tuberculosis (XXDR)- case report and its clinical implications.

Black Hairy Tongue(BHT)/Black tongue is usually an asymptomatic cosmetic nuisance, characterized by hyperkeratosis of the elongated filiform lingual papillae ('hairs'). Black hairy tongue is well known with various drugs. Due to this sign, many a times the drugs are withdrawn and replaced with other drugs. Imipenem and linezolid are the drugs used as antimicrobial drugs in a number of infections but has been repurposed in drug resistant tuberculosis. A case was referred to us who failed on longer MDR treatment for 14 months for further management. DST revealed resistance to 10 drugs and clinical resistance to additional 4 drugs, totalling 14 drugs amounting to extremely drug resistant tuberculosis(XXDR) coined for patients much beyond XDR TB. We put the patient on individualized regime which contained Imipenem, Amikacin, high dose moxifloxacin and Delaminid. Linezolid could not be used due to anaemia but introduced one month later. Patient developed BHT within a week, disappeared on withdrawing the Imipenem but reappeared on reintroduction. Imipenem causing BHT is reported in one case only in last 4 decades of its use as antimicrobial. We are reporting the second case. Patient also developed BHT and blackening of teeth with Linezolid. As Imipenem-cilastatin and Linezolid are important drugs especially in difficult to treat tuberculosis, instead of stopping them we continued with the above drugs despite persistence of black tongue and teeth under close supervision during the whole 18 months without any further complications and patient was cured. Black tongue and teeth also disappeared after stopping the treatment.