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Linezolid induced black hairy tongue

Govindan Balaji, B. Maharani1, Velappan Ravichandran, Thiyagarajan Parthasarathi2

ABSTRACT Departments of Dermato-Venereology and Black hairy tongue (BHT) also called as lingua villosa nigra, is a self limiting benign 2Orthopedics, Government Mohan condition characterized by hypertrophy and elongation of fi liform papillae of tongue Kumaramangalam Medical College with brown or black discoloration. Smoking, poor oral hygiene, xerostomia, using 1 Hospital, Salem, Department peroxide containing mouth washes, substance abuse and drugs (steroids, methyldopa, of Pharmacology, Annapoorana olanzapine, etc) are the predisposing factors. However its occurrence in relation to Medical College and Hospitals, linezolid ingestion among south Indians has not been reported in PubMed database. Here Salem, Tamil Nadu, India we report a case, where signifi cant association of linezolid intake with BHT was found in a 10-year-old boy, who was treated with tablet linezolid for post surgical infection Received: 25-04-2014 Revised: 10-05-2014 of left side radial neck fracture. This case is reported for the rarity of occurrence with Accepted: 27-07-2014 linezolid therapy. According to Naranjo adverse drug reaction (ADR) causality scale, the association of BHT due to linezolid in our case was probable. Correspondence to: Dr. B. Maharani, KEY WORDS: Black hairy tongue, linezolid, Naranjo algorithm E-mail: [email protected]

Introduction Case Report Black Hairy Tongue (BHT) is a self limiting benign condition, A 10-year-old boy was referred from orthopaedic characterized by elongation and hypertrophy of filiform department for the complaint of black discoloration of papillae of tongue with brown or black discoloration on the dorsum of tongue for 4 days duration. He was treated posterior dorsum of tongue.[1] Increase in keratin production or with tablet linezolid 600 mg twice daily for two weeks for decrease in normal desquamation may lead to accumulation of post surgical infection of left side radial neck fracture. The keratinized layers.[2] BHT is usually asymptomatic, sometimes boy reported the blackish pigmentation of the posterior patients may complain of nausea, halitosis, dysguesia, tickling aspect of dorsum of tongue on the fourteenth day of tablet of the tongue.[1] Smoking or chewing tobacco, poor oral linezolid. On examination of the oral cavity, black to brown hygiene, xerostomia, substance abuse like cocaine, using discoloration was seen in the posterior aspect of dorsal peroxide containing mouth washes and drugs like steroids, surface of tongue, with elongated and hypertrophied filiform bismuth, methyldopa, tetracycline are the predisposing papillae [Figure 1]. Complete hemogram was normal. Parents factors.[3] Interestingly, olanzapine along with lithium produced did not give consent for biopsy of the lesion. Linezolid was recurrent black hairy tongue in bipolar disorder patient.[4] The stopped after the tongue discoloration. Patient was asked incidence of black hairy tongue in patients receiving linezolid to clean his tongue with normal saline twice daily. Patient was 0.2% in a large controlled study done by Hau.T.[5] There is was followed after 7 days and the discoloration of tongue no case report of black hairy tongue in south Indians due to totally disappeared [Figure 2]. Total disappearance of lesion in linezolid therapy found through PubMed search. Here we 11 days after stopping linezolid]. Employing the Naranjo ADR report a rare case of linezolid induced black hairy tongue in probability scale to find out the association of linezolid intake a 10-year-old boy. to black hairy tongue, the score was five, which revealed a probable adverse drug reaction. The clinical findings and Access this article online Naranjo probability scale had suggested the diagnosis of Quick Response Code: black hairy tongue due to linezolid therapy. Website: www.ijp-online.com

DOI: 10.4103/0253-7613.144942 Discussion Using the Naranjo’s Adverse Drug Reaction Probability Scale, we present a case of probable linezolid-induced BHT in a 10-year-old boy. The patient was not on any other medications except linezolid. Other known causes of BHT were ruled out.

Indian Journal of Pharmacology | December 2014 | Vol 46 | Issue 6 653 Balaji, et al.: Linezolid induced black hairy tongue

Figure 1: Black hairy tongue in a ten year old boy on linezolid Figure 2: Photo after stopping linezolid therapy

Linezolid is an oxazolidinone derivative mainly indicated Conclusion for infections caused by methicillin-resistant staphylococci Linezolid induced BHT is a rare and benign disorder. Other and vancomycin-resistant enterococci. The most common predisposing factors should be excluded before diagnosing side effects of linezolid are nausea, vomiting and headache. linezolid induced BHT. The patient on linezolid therapy should Reversible bone marrow suppression and neuropathy would be advised to maintain a good oral hygiene to prevent the occur, if the duration of the drug intake is more than 4 weeks. development of BHT. Further investigations are needed to find The median time duration of development of black hairy out the pathogenesis for linezolid induced black hairy tongue. tongue after starting linezolid in previous case reports were References two weeks.[6] Petropoulau T et al., described the association of linezolid with both black hairy tongue and discoloration of 1. Thompson DF, Kessler TL. Drug-induced black hairy tongue. Pharmacotherapy [7] 2010;30:585-93. teeth in three children. 2. Manabe M, Lim HW, Winzer M, Loomis CA. Architectural organization of fi liform Defective desquamation of keratinized layer of tongue papillae in normal and black hairy tongue epithelium: Dissection of differentiation leads to excessive growth and thickening of filiform papillae pathways in a complex human epithelium according to their patterns of keratin of tongue which leads to collection of microorganisms or expression. Arch Dermatol 1999;135:177-81. 3. Sarti GM, Haddy RI, Schaffer D, Kihm J. Black hairy tongue. Am Fam Physician foreign material. The exact mechanism behind drug induced 1990;41:1751-5. BHT is not known.[6] The diagnosis of drug induced black 4. Tamam L, Annagur BB. Black hairy tongue associated with olanzapine treatment: hairy tongue depends upon the visual inspection of the A case report. Mt Sinai J Med 2006;73:891-4. discolored, elongated and hypertrophied filiform papillae. 5. Hau T. Effi cacy and safety of linezolid in the treatment of skin and soft tissue infections. Eur J Clin Microbiol Infect Dis 2002;21:491-8. Detailed history of the patient helps us to identify the 6. Khasawneh FA, Moti DF, Zorek JA. Linezolid induced black hairy tongue: A case offending drug and the associated contributing factors. report. J Med Case Rep 2013;7:46. Treatment of the black hairy tongue is immediate withdrawal 7. Petropoulou T, Lagona E, Syriopoulou V, Michos A. Teeth and tongue discoloration after linezolid treatment in children. Paediatr Infect Dis J 2013;32:1284-5. of the offending drug and proper tongue debridement. In 8. Langtry JA, Carr MM, Steele MC, Ive FA. Topical tretinoin: A new treatment for persistent type, it could be treated with 40% urea, salicylic black hairy tongue (lingua villosa nigra). Clin Exp Dermatol 1992;17:163-4. acid and surgical excision.[8] This case is presented for its rarity in occurrence induced by linezolid in a 10-year-old Cite this article as: Balaji G, Maharani B, Ravichandran V, Parthasarathi T. boy and to create awareness among physicians about this Linezolid induced black hairy tongue. Indian J Pharmacol 2014;46:653-4. rare side effect. Source of Support: Nil. Confl ict of Interest: No.

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