Architectural organization of filiform papillae in normal and black hairy tongue epithelium: dissection of differentiation pathways in a complex human epithelium according to their patterns of keratin expression

A Case Report of a Co-Amoxiclav-Induced Black Hairy Tongue

A black hairy tongue is a benign, self-limiting condition characterized by the discolouration of the tongue due to defective desquamation. Clinical presentation varies, with most cases being asymptomatic although aesthetically unpleasant to the patient. Prevalence varies geographically, ranging from 0.6% to 11.3%. It can be triggered by various factors such as medications, smoking, alcohol, poor oral hygiene, or even underlying systemic conditions such as malignancy. Several antibiotics such as doxycycline, erythromycin, amoxicillin-clavulanate, metronidazole, and piperacillin-tazobactam, have been reported to cause black hairy tongues. Onset can range from a few weeks to as long as five weeks. Diagnosis relies on clinical assessment with a good history and visual examination. Definitive treatment remains unclear, but the condition typically improves by identifying and discontinuing the causative agent and maintaining adequate oral hygiene. Complications are rare, and the prognosis is excellent. This case report aims to raise awareness of the association between the black hairy tongue and co-amoxiclav, which may impose additional burdens on patients, healthcare providers, and the health system if failed to be recognized and treated appropriately.

Long-term use of triple antibiotic-induced black hairy tongue: A case report

Black hairy tongue is a rare condition, characterized by a black discoloration and hair-like structure appearing on the dorsal surface of the tongue. The mechanism of black hairy tongue remains unclear but could be predisposed by multiple factors. We described a case of a 53-year-old Chinese female with a diagnosis of bronchiectasis complicated with Mycobacterium abscessus infection, and a triple antibiotic regimen was prescribed for the infection. One month later, a black hairy tongue appeared. The clinical pharmacist was consulted to investigate the association of medication-related factors by the attending clinician, and the clinical pharmacist identified the potential cause and suggested an appropriate treatment for the black hairy tongue. The black hairy tongue disappeared and did not recur during subsequent treatment.

Black hairy tongue after alprazolam intake

Key Clinical Message

A 31-year-old female with a diagnosis of bipolar disorder developed black hairy tongue after alprazolam therapy. Her symptom resolved 10 days after the cessation of alprazolam.

Abstract

Alprazolam is a widely used antidepressant and antianxiety drug. Mild to moderate side effect of alprazolam was commonly seen, including lethargy, dizziness, headache, dry mouth, nausea, fatigue, constipation, and blurred vision. In this case, we reported a patient developed black hairy tongue after alprazolam intake, and her symptom resolved after 10-day discontinuation of alprazolam. This rare adverse event should be of concern to clinicians. This is the first paper to report an alprazolam-induced BHT. This rare side effect of alprazolam should be concern of clinicians; we hope our report will promote the understand of BHT and acknowledge clinicians of this rare side effect of alprazolam.

Oral Bacteria Dysbiosis in Patients with Linezolid-Induced Black Hairy Tongue: A Case Series

Linezolid-induced black hairy tongue is a self-limiting benign disease that is rare. Here, we report three patients who developed black hairy tongue after linezolid treatment. The severe dysbiosis of oral bacterial communities was observed in all these patients. Proteobacteria was the most prevalent phylum (over 90%) at the black tongue stage. Furthermore, the dramatic oral bacterial alteration took a long time to reverse after the BHT resolved.

Elucidation of a lingual detection mechanism for high-viscosity solutions in humans

While perception of high-viscosity solutions (η > 1000 cP) is speculated to be linked to filiform papillae deformation, this has not been demonstrated psychophysically. Presently, just-noticeable-viscosity-difference thresholds were determined using the forced-choice staircase method and high-viscosity solutions (η = 4798-12260 cP) with the hypotheses that the tongue would be chiefly responsible for viscosity perception in the oral cavity, and that individuals with more, longer, narrower filiform papillae would show a greater acuity for viscosity perception. Subjects (n = 59) evaluated solutions in a normal, "unblocked" condition as well as in a "palate blocked" condition which isolated the tongue so that only perceptual mechanisms on the lingual tissue were engaged. Optical profiling was used to characterize papillary length, diameter, and density in tongue biopsies of a subset (n = 45) of participants. Finally, psychophysical and anatomical data were used to generate a novel model of the tongue surface as porous media to predict papillary deformation as a strain-detector for viscosity perception. Results suggest that viscosity thresholds are governed by filiform papillae features. Indeed, anatomical characterization of filiform papillae suggests sensitivity to high-viscosity solutions is associated with filiform papillae length and density (r = 0.68, p < 0.00001), but not with diameter. Modelling indicated this is likely due to a reciprocal interaction between papillae diameter and fluid shear stress. Papillae with larger diameters would result in higher viscous shear stress due to a narrower gap and stronger fluid-structure interaction, but a larger-diameter papilla would also deform less easily.

Diode Laser Surgery as a Conservative Management of Hairy Tongue Lesion Resistance to Treatment

Hairy tongue is a furry appearance on the dorsum surface of the tongue with variable colors. This lesion is due to defective shedding of filiform papillae. Various treatments are proposed for this condition like keratolytic agents, surgical procedure with a scalpel, or laser application. In this case study, we reported successful treatment of hairy tongue with a diode laser. The diode laser with wavelength 810 nm, power of 4 watts, a pulse width of 20 milliseconds, and an interval of 20 milliseconds by a 400-micron optical fiber was selected for treatment of this lesion. There was no bleeding during this minimally invasive surgery, and the patient experienced a low level of pain. Loss of taste function was completely resolved. Based on the result of this study, a diode laser can be a good alternative for minimally invasive surgical treatment of hairy tongue.

Spatial Ecology of the Human Tongue Dorsum Microbiome

A fundamental question in microbial ecology is how microbes are spatially organized with respect to each other and their host. A test bed for examining this question is the tongue dorsum, which harbors a complex and important microbial community. Here, we use multiplexed fluorescence spectral imaging to investigate the organization of the tongue microbiome at micron to hundred-micron scales. We design oligonucleotide probes for taxa both abundant and prevalent, as determined by sequence analysis. Imaging reveals a highly structured spatial organization of microbial consortia, ranging in linear dimension from tens to hundreds of microns. The consortia appear to develop from a core of epithelial cells, with taxa clustering in domains suggestive of clonal expansion. Quantitative proximity analysis provides the basis for a model of tongue dorsum microbiome organization and dynamics. Our work illustrates how high-resolution analysis of micron-scale organization provides insights into physiological functions and microbiome-host interactions.

How microbes are spatially organized is a fundamental question in microbial ecology about which little is known. Using fluorescence spectral imaging, Wilbert et al. discover dense, highly structured microbial consortia on the human tongue. Analysis of the organization of these consortia permits inferences about community dynamics and oral microbial ecology.

Concurrent chronic hyperplastic candidosis and oral lichenoid lesion as adverse events of secukinumab therapy

Secukinumab (Cosentyx®) is an IL-17A inhibitor which is used for the management of psoriasis, active psoriatic arthritis or ankylosing spondylitis. Oral adverse events of secukinumab therapy are not widely appreciated. This article highlights the presentation of two concurrent oral adverse events of secukinumab therapy; namely chronic hyperplastic candidosis (CHC) and oral lichenoid lesion (OLL). This is the first documented case report of CHC occurring as a consequence of secukinumab therapy, and represents a new adverse effect which general and specialist oral health practitioners should be aware of. This case highlights the importance of correlating the presence of oral lesions with the patient's medical history, keeping up to date with the development of new medications and pharmacotherapeutics, having a deep understanding of underlying biological processes related to various oral diseases, and appreciating the use of clinical adjunctive devices. Accurate diagnosis is key to formulating a correct management plan.

A Case of Lingua Villosa Nigra (Black Hairy Tongue) in a 3-Month-Old Infant

BACKGROUND Black hairy tongue is a self-limiting, usually asymptomatic, benign lesion that most often affects men and people aged over 30-40 years. The lesion is extremely rare among newborns and infants. Lingua villosa nigra is characterized by the presence of elongated filiform papillae of the dorsum of the tongue, which gives a hairy appearance. The overgrown papillae can accumulate fungi, bacteria, pigments originating from food, or any other debris that can contribute to the discoloration of the tongue. The prognosis for black hairy tongue is positive. Gentle tongue brushing or scraping as well as the elimination of predisposing factors usually leads to cessation of the lesion. CASE REPORT A generally healthy, exclusively breastfed 3-month-old female baby was admitted to the Oral Pathology Department of Wrocław Medical University due to a persistent tongue lesion. Intraorally, dark, blackish, elongated tongue papillae were observed. Three weeks earlier, the baby's pediatrician had diagnosed thrush and prescribed systemic antifungal treatment with Nystatinum, without prior mycological examination. The lesion did not resolve and the girl was referred to the Department of Oral Pathology. A meticulous medical and dietary interview revealed that since the 28th day of life the baby had been supplemented with vitamin C. This, together with an intraoral examination, led to the diagnosis of black hairy tongue. The lesion disappeared partially after 4 weeks of tongue brushing. CONCLUSIONS To prevent infants from undergoing persistent and unnecessary treatment (topical or systemic drugs) or additional diagnostic procedures, such as biopsy, it is essential to be familiar with the characteristics of lingua villosa nigra as well as its origin and management. The consideration of this condition is invaluable for babies' health and safety.

Polycomb Repressive Complex 1 Controls Maintenance of Fungiform Papillae by Repressing Sonic Hedgehog Expression

How tissue patterns are formed and maintained are fundamental questions. The murine tongue epithelium, a paradigm for tissue patterning, consists of an array of specialized fungiform papillae structures that harbor taste cells. The formation of fungiform papillae is preceded by pronounced spatial changes in gene expression, in which taste cell genes such as Shh, initially diffused in lingual epithelial progenitors, become restricted to taste cells when their specification progresses. However, the requirement of spatial restriction of taste cell gene expression for patterning and formation of fungiform papillae is unknown. Here, we show that a chromatin regulator, Polycomb repressive complex (PRC) 1, is required for proper maintenance of fungiform papillae by repressing Shh and preventing ectopic SHH signaling in non-taste cells. Ablation of SHH signaling in PRC1-null non-taste cells rescues the maintenance of taste cells. Altogether, our studies exemplify how epigenetic regulation establishes spatial gene expression patterns necessary for specialized niche structures.

Formation and maintenance of patterns are critical for tissue development. Bar et al. show that PRC1, an epigenetic regulator, is critical for lingual papillae development. Specifically, PRC1 regulates maintenance of the developing fungiform papillae, harboring taste cells, by repressing Shh expression in the non-gustatory epithelium surrounding taste cells.

Taste of time: A porous-medium model for human tongue surface with implications for early taste perception

Most sensory systems are remarkable in their temporal precision, reflected in such phrases as “a flash of light” or “a twig snap”. Yet taste is complicated by the transport processes of stimuli through the papilla matrix to reach taste receptors, processes that are poorly understood. We computationally modeled the surface of the human tongue as a microfiber porous medium and found that time-concentration profiles within the papilla zone rise with significant delay that well match experimental ratings of perceived taste intensity to a range of sweet and salty stimuli for both rapid pulses and longer sip-and-hold exposures. Diffusivity of these taste stimuli, determined mostly by molecular size, correlates greatly with time and slope to reach peak intensity: smaller molecular size may lead to quicker taste perception. Our study demonstrates the novelty of modeling the human tongue as a porous material to drastically simplify computational approaches and that peripheral transport processes may significantly affect the temporal profile of taste perception, at least to sweet and salty compounds.

Taste perception is an important gateway for food selection, food intake, energy and nutrition balance–as world is facing epidemic of obesity and diabetes. Information conveyed via the taste system provide crucial behavior choices, e.g. in identifying edible and nutritious food source, driving hedonic evaluation and craving, as well as avoiding poisonous substances. Thus, the interest to understand early taste responses is important, not only for basic science, but also for clinical and public health applications.

Keratin 36, a specific marker of tongue filiform papillae, is downregulated in squamous cell carcinoma of the mobile tongue

Human keratin 36 (K36) is a member of the hair keratin family and is a marker of hair cortex differentiation. The human KRT36 gene is located on the long arm of chromosome 17 and belongs to the cluster of structurally unrelated acidic hair keratins. Recently, it has been reported that KRT36 mRNA is specifically expressed in normal tongue epithelium and downregulated in squamous cell carcinomas of the mobile tongue. Furthermore, KRT36 levels have been reported to be downregulated in clinically normal mobile tongue tissue that is adjacent to tumours, suggesting it could be a marker of pre-neoplastic changes. However, the exact role and the potential role of K36 in tongue tumour formation remains unclear. The aim of the present study was to investigate expression of K36 in a series of squamous cell carcinomas of the mobile tongue, normal mobile tongue and a small panel of other human tissues (normal tissue from the appendix, cervix, hair, lip, mamilla, nail, oesophagus, skin, thymus and vagina) and selected cancer tissue (cervical cancer, melanoma and basal cell carcinoma). Affinity purified polyclonal antibodies against K36 were generated and used for immunohistochemical analysis. The results revealed that in the normal tongue, K36 was detected specifically in the filiform papillae of the dorsal surface of the tongue. Additionally, none of the tongue cancer tissue samples were K36-positive. Immunostaining also revealed that K36 was expressed in nail beds, Hassal's corpuscles in the thymus and the hair cortex. However, K36 was not expressed in the squamous epithelia of the skin, cervix and oesophagus, and the squamous cells of cervical carcinomas, basal cell carcinoma or melanoma. The present data indicated that K36 may be inactivated in tumours of the tongue. However, whether this is part of the tumoural process or if it is an effect of the tumour itself remains to be elucidated.

Hairy Tongue: Differential Diagnosis by Use of Widefield Optical Fluorescence

Hairy tongue is a benign pathology, characterized clinically by hyperkeratinized plaques on the dorsal surface of the tongue, hairlike, whose coloration ranges from unpigment, whitish, yellowish, green, brown to black. Diagnosis is clinical, and, in cases of whitish plaques, it may be difficult to differentiate between oral hairy leukoplakia, potentially malignant leukoplakia or squamous cell carcinoma. Thus, widefield optical fluorescence complementary examination may allow a better visualization of the local hairlike pattern of hyperkeratinization, typical of the hairy tongue, facilitating the diagnosis. In this work, a 57-year-old man was referred to the Dental Specialties Department of the Divinópolis Health Department (MG, Brazil) by a general dental practitioner, aiming a differential diagnosis of possible malignant lesion on the dorsal tongue surface. The complementary examination by wide-field optical fluorescence was performed. For this, it was employed a device with high-power light-emitting diode emitting light centered at a wavelength of (400±10) nm and maximum irradiance of (0.040±0.008) W/cm2 was used for fluorescence visualization. Fluorescence images showed projections of hairlike appearance in tongue dorsal surface with no aspects of malignancy. Hairlike appearance is the principal feature of hairy tongue. In this way, the final diagnosis was established. In conclusion, in this case, the use of widefield optical fluorescence in oral diagnostic routine provided a differential diagnosis, with no need of an incisional biopsy.

Black and Brown: Non-neoplastic Pigmentation of the Oral Mucosa

Black and brown pigmentation of the oral mucosa can occur due to a multitude of non-neoplastic causes. Endogenous or exogenous pigments may be responsible for oral discoloration which can range from innocuous to life-threatening in nature. Physiologic, reactive, and idiopathic melanin production seen in smoker's melanosis, drug-related discolorations, melanotic macule, melanoacanthoma and systemic diseases are presented. Exogenous sources of pigmentation such as amalgam tattoo and black hairy tongue are also discussed. Determining the significance of mucosal pigmented lesions may represent a diagnostic challenge for clinicians. Biopsy is indicated whenever the source of pigmentation cannot be definitively identified based on the clinical presentation.

Linezolid-induced black hairy tongue

Black hairy tongue (BHT) is a self-limiting disorder characterized by abnormal hypertrophy and elongation of filiform papillae on the surface of the tongue. The exact mechanism of drug-induced BHT is unknown. Several factors have been implicated and included smoking or chewing tobacco, drinking alcohol, poor oral hygiene and antibiotics such as tetracyclines and penicillins. We report a quite uncommon case of Linezolid-induced BHT in a patient with a long-lasting history of chest wall infection (www.actabiomedica.it)

Dermoscopic patterns of filiform papillae of the tongue in patients with and without connective tissue autoimmune diseases

BACKGROUND

Connective tissue autoimmune diseases (CTADs) constitute a group of conditions, including rheumatoid arthritis; systemic lupus erythematosus; mixed connective tissue disease; calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia (CREST) syndrome; scleroderma; dermatomyositis; and Sjögren syndrome. There are few studies on the alterations in filiform papillae in CTAD. Thus, the objective of this work was to determine whether there are changes in the macroscopic and dermoscopic patterns of filiform papillae.

METHODS

This case-control study included patients who were diagnosed with CTAD. The dependent variable was the dermoscopic pattern of filiform papillae of the tongue, and the independent variables were age, gender, time of evolution, and current treatment. A photograph of the back of the tongue was taken, and subsequently, the same site was examined by dermatoscopy. The microscopic and dermoscopic patterns of filiform papillae were classified (Maeda).

RESULTS

We included 50 cases and 50 controls, 94% of whom were female. The mean age was 43.96 ± 14.65 years. Of the cases with CTAD, 25% presented with a normal macroscopic pattern, versus 36% (18) with pattern II, 12% (6) with pattern III, and 20% (10) with pattern IV. The dermoscopic pattern was type I in 23 cases (46%), type II in 16 (32%), type III in 10 (20%), and type IV in one patient (2%).

CONCLUSIONS

We have noted alterations in filiform papillae in CTADs, which emphasizes the importance of a detailed intraoral exploration and the macroscopic and dermoscopic evaluation of the dorsum of the tongue, specifically the filiform papillae.

Prevalence of Oral Mucosal Lesions among Dental Patients with Mixed Habits in Salem District - A Study

BACKGROUND

The practice of betel nut chewing with or without tobacco is still practiced in south india, salem inspite of its harmful effects.

METHODOLOGY

200 Patients visiting the outpatient department, Oral medicine and radiology from Aug 2015 to Aug 2016.

RESULT AND CONCLUSION

In our study, 3 women were exclusively churut smokers. Thirty-eight percent of the dental patients were beedi smoker, 32% were tobacco chewers, 12% were both betel nut and tobacco chewers, 8% were exclusively betel nut chewers, 1% of the dental population were exclusively churut smokers. Mean age group of the study population is 50.2 (14.4). There are 28 females and 172 males in the study group. Chi-square test revealed a statistically significant difference (P = 0.001) between males and females based on soft-tissue findings and no statistically significant difference (P = 0.572) between males and females based on distribution of hard-tissue findings.

Black Hairy Tongue: Predisposing Factors, Diagnosis, and Treatment

Black hairy tongue (BHT) is a benign condition commonly found among people who smoke, have poor oral hygiene, are immunocompromised, or have a medical condition limiting their ability to practice good oral hygiene. Though this condition is harmless, patients need to be educated on etiology as many common medications are associated with this condition. Patients being placed on certain antibiotics or antipsychotics should be educated on the importance of good oral hygiene or cessation of habits that promote BHT. Similarly, those with medical conditions increasing the risk for the development of BHT should schedule routine visits with their dentist or dental hygienist. Prognosis is good, and treatment consists of gentle brushing of the tongue, but many anecdotal reports exist demonstrating the use of medications or other products to treat this condition. This review addresses the epidemiology, clinical presentation, pathophysiology, etiology, histology, differential diagnosis, and treatment of BHT and lists all of the medications reported to cause this condition.

Tongue and Taste Organ Biology and Function: Homeostasis Maintained by Hedgehog Signaling

The tongue is an elaborate complex of heterogeneous tissues with taste organs of diverse embryonic origins. The lingual taste organs are papillae, composed of an epithelium that includes specialized taste buds, the basal lamina, and a lamina propria core with matrix molecules, fibroblasts, nerves, and vessels. Because taste organs are dynamic in cell biology and sensory function, homeostasis requires tight regulation in specific compartments or niches. Recently, the Hedgehog (Hh) pathway has emerged as an essential regulator that maintains lingual taste papillae, taste bud and progenitor cell proliferation and differentiation, and neurophysiological function. Activating or suppressing Hh signaling, with genetic models or pharmacological agents used in cancer treatments, disrupts taste papilla and taste bud integrity and can eliminate responses from taste nerves to chemical stimuli but not to touch or temperature. Understanding Hh regulation of taste organ homeostasis contributes knowledge about the basic biology underlying taste disruptions in patients treated with Hh pathway inhibitors.

Advantages and Limitations of Salmon-Gal/Tetrazolium Salt Histochemistry for the Detection of LacZ Reporter Gene Activity in Murine Epithelial Tissue

The Escherichia coli LacZ gene is a widely used reporter for gene regulation studies in transgenic mice. It encodes bacterial β-galactosidase (Bact β-Gal), which causes insoluble precipitates when exposed to chromogenic homologues of galactose. We and others have recently reported that Bact β-Gal detection with Salmon-Gal (S-Gal) in combination with nitro blue tetrazolium chloride (NBT) is very sensitive and not prone to interference by acidic endogenous β-galactosidases. Unfortunately, as we show here, the method appears to be inadequate for evaluation of Bact β-Gal expression in keratinized epithelial appendages but not in other keratinized epithelia. NBT in the reaction mixture, just as other tetrazolium salts, inevitably causes unwanted staining artifacts in lingual filiform papillae, penile spines, and hair fibers by interacting with keratin sulfhydryl-rich regions. The methodological limitation can be overcome in part by pretreating the tissues before the S-Gal/NBT staining with an iodine-potassium iodide solution. Alternatively, the use of iodonitrotetrazolium chloride instead of NBT in the S-Gal reaction mixture provides enough color resolution to distinguish the specific Bact β-Gal staining in orange from the artifact staining in dark red. In summary, we provide evidence that S-Gal/NBT histochemistry has limitations, when staining keratinized epithelial appendages.

Black hairy tongue after chemotherapy for malignant brain tumors

Black hairy tongue (BHT) developed in five patients (2.6%) among 192 patients undergoing chemotherapy for malignant brain tumors. Three patients with a history of diabetes mellitus developed BHT within 10 days after the initiation of chemotherapy. The other two patients suffered more than 100 days after induction and lymphopenia of grade 3 or worse developed for more than 20 days, which was not observed in the three patients with diabetes. We found that BHT could develop after chemotherapy for malignant brain tumors. Patients with diabetes mellitus presented early after chemotherapy, while patients with longstanding severe lymphopenia presented in late phase.

Black hairy tongue in a patient with amyotrophic lateral sclerosis

Black hairy tongue (BHT) is a condition characterized by the elongation of filiform papillae associated with a marked discoloration, from yellowish-brown to black, and a thick lingual coating. BHT is usually observed in the elderly and in patients with limited self-sufficiency, as a consequence of poor oral hygiene. In this perspective, the patients affected by amyotrophic lateral sclerosis (ALS) represent a high-risk category for the occurrence of BHT. The fast and inexorable loss of their self-sufficiency due to progressive muscle atrophy as well as the impropriate education of healthcare assistants have demonstrated to have significant reflection on the maintenance of an adequate standard of oral hygiene. This paper firstly described a case of BHT in a patient affected by ALS. A case of BHT in a patient (Caucasic, male, 63 years old) affected by ALS was described. The primary goal of the work was to teach and motivate the patient to the use of the tongue cleaner in association with the local application of chlorexidine 0.20%. Furthermore, in order to support the patient with accurate domiciliary oral hygiene, a proper training for his health-care assistant was provided. The maintenance of the oral health of ALS patient is fundamental to prevent systemic complications that could jeopardize the already fragile physical balance of these patients. The dedicated monitoring by a dentist or a dental hygienist would seem essential in order to achieve this objective.

Linezolid induced black hairy tongue

Black hairy tongue (BHT) also called as lingua villosa nigra, is a self limiting benign condition characterized by hypertrophy and elongation of filiform papillae of tongue with brown or black discoloration. Smoking, poor oral hygiene, xerostomia, using peroxide containing mouth washes, substance abuse and drugs (steroids, methyldopa, olanzapine, etc) are the predisposing factors. However its occurrence in relation to linezolid ingestion among south Indians has not been reported in PubMed database. Here we report a case, where significant association of linezolid intake with BHT was found in a 10-year-old boy, who was treated with tablet linezolid for post surgical infection of left side radial neck fracture. This case is reported for the rarity of occurrence with linezolid therapy. According to Naranjo adverse drug reaction (ADR) causality scale, the association of BHT due to linezolid in our case was probable.

Black hairy tongue syndrome

Black hairy tongue (BHT) is a benign medical condition characterized by elongated filiform lingual papillae with typical carpet-like appearance of the dorsum of the tongue. Its prevalence varies geographically, typically ranging from 0.6% to 11.3%. Known predisposing factors include smoking, excessive coffee/black tea consumption, poor oral hygiene, trigeminal neuralgia, general debilitation, xerostomia, and medication use. Clinical presentation varies but is typically asymptomatic, although aesthetic concerns are common. Differential diagnosis includes pseudo-BHT, acanthosis nigricans, oral hairy leukoplakia, pigmented fungiform papillae of the tongue, and congenital melanocytic/melanotic nevi/macules. Clinical diagnosis relies on visual observation, detailed history taking, and occasionally microscopic evaluation. Treatment involves identification and discontinuation of the offending agent, modifications of chronic predisposing factors, patient's re-assurance to the benign nature of the condition, and maintenance of adequate oral hygiene with gentle debridement to promote desquamation. Complications of BHT (burning mouth syndrome, halitosis, nausea, gagging, dysgeusia) typically respond to therapy. Prognosis is excellent with treatment of underlying medical conditions. BHT remains an important medical condition which may result in additional burden on the patient and health care system and requires appropriate prevention, recognition and treatment.

Linezolid-induced black hairy tongue: a case report

INTRODUCTION

Linezolid-induced black hairy tongue has been rarely reported. The purpose of this paper is to report a case of linezolid-induced black hairy tongue and review the literature.

CASE PRESENTATION

A 56-year-old Caucasian man was admitted with community-acquired pneumonia that failed to respond to levofloxacin 750mg daily. He was started on linezolid and meropenem and was subsequently discharged home on oral linezolid 600mg every 12 hours and intravenous ertapenem 1g daily. On a follow-up clinic visit, day 14 of linezolid therapy, he complained of dysgeusia and his tongue examination was consistent with black hairy tongue. After he finished his antibiotic course, his complaints resolved with regular tongue brushing.

CONCLUSION

Black hairy tongue is characterized by abnormal hypertrophy and elongation of filiform papillae. Five reported cases of linezolid-induced black hairy tongue were identified in a MEDLINE search (from January 2000 to June 2012). The Naranjo Probability Scale revealed a probable adverse drug reaction of linezolid-induced black hairy tongue. Potential contributing factors included other antibiotics, drug-drug interaction and poor oral hygiene. Health care professionals should be aware of the possibility of linezolid-induced black hairy tongue. Thorough history for other possible contributing factors should be obtained. Patients on linezolid should be counseled to perform good oral hygiene.

Black hairy tongue associated with erlotinib treatment in a patient with advanced lung cancer

Erlotinib is a tyrosine kinase inhibitor that acts on the epidermal growth factor receptor (EGFR). There have been many reports of the mucocutaneous side effects related to several EGFR inhibitors (EGFRIs). However, no case of black hairy tongue (BHT) associated with EGFRI has been reported. Herein, we report the first case of erlotinib-induced BHT in a 61-year-old man with advanced lung cancer. Considering recent use of EGFRIs worldwide, dermatologists should recognize the possible occurrence of BHT associated with EGFRIs such as erlotinib.

Black hairy tongue after allogeneic stem cell transplantation: an unrecognized cutaneous presentation of graft-versus-host disease

Black hairy tongue (BHT) is an unusual condition in adults characterized by marked accumulation of keratin on the dorsum of the tongue, resulting in a hair-like appearance. Herein, we have described 15 patients developing BHT after allogeneic stem cell transplantation (allo-SCT). BHT was generally accompanied by other cutaneous manifestations of cutaneous graft-versus-host disease (GVHD) or a precursor of GVHD. Our experience in this series emphasized that histopathologic evaluation is required for seemingly harmless eruptions like BHT in the posttransplantation period. Given the important prognostic implications of GVHD, physicians should be careful when confronted with BHT.

Atrophic change of tongue papilla in 44 patients with Sjögren syndrome

OBJECTIVE

The purpose of this study was to investigate the atrophic change of tongue papilla in Sjögren syndrome (SjS) patients and the correlation with characteristic features of the disease.

STUDY DESIGN

Atrophic change of tongue papilla, investigated by a digital microscope, was classified from score 0 (normal) to score 6 (severe) and compared among 44 SjS patients, 20 xerostomia patients, and 20 healthy subjects. In SjS patients, correlation of the atrophic score of tongue papilla with characteristic changes in sialometry, sialography, lip biopsy, and serologic tests was also investigated.

RESULTS

The atrophic score of tongue papilla was significantly higher in SjS patients and correlated with the decrease of salivary secretion, the stage on sialography, and the histologic grade of the minor salivary gland.

CONCLUSION

Atrophic change of tongue papilla is significant in SjS patients and is correlated with the characteristic features of the disease.

Scrape cytology in rare case of hairy tongue

Hairy tongue (HT) is a benign condition that causes concern over its abnormal appearance. HT is most commonly seen in adults and is seen as an abnormal coating of the tongue due to hyperkeratosis of filiform lingual papillae. Cytological scraping of the lesion on the tongue was done which showed squamous cells, extraneous material, bacterial colonies, fungal bodies, and hair-like projections, which are the hall mark of the disease. We present a case along with its scrape cytology findings.

Evaluation of oral mucosal lesions in 598 referred Iranian patients

The mucosal membrane of the oral cavity displays at times classical developmental lesions considered to be variations of normal structures rather than having disease characteristics. Of these lesions leukoedema, Fordyce granules, geographic-, fissured- and hairy tongue, median rhomboid glossitis and lingual varices were studied in 598 patients referred to the School of Dentistry, Tehran, Iran. The prevalence was studied in relation to age, gender, occupation, education, smoking habits, general health, addictions and or drug therapies. Oral developmental lesions were seen in 295 patients (49.3%). Only Fordyce granules (27,9%), fissured tongue (12,9%), leukoedema (12,5%) and hairy tongue (8,9%) had enough cases for statistical analysis. Three of these lesions increased with age but not fissured tongue. All were more common in men. After adjusting for age, the parameters education, occupation and complaints upon referral had little influence on the prevalence of the lesions. Fewer Fordyce granules were seen in oral mucosa of smoking men. Leukoedema and hairy tongue were significantly associated with smoking, leukoedema with diabetes mellitus. We conclude that there was a highly significant association between these oral lesions and age, gender and smoking. Few significant associations were found between oral lesions and general diseases.

Black hairy tongue in a 2-month-old infant

Black hairy tongue (BHT) is an unusual condition in adults, and is characterised by marked accumulation of keratin on the filiform papillae of the dorsum of the tongue resulting in a hairlike appearance. The colour of the papillae may vary from brown to black. We describe a case of BHT in a 2-month-old infant. An extended review of the literature suggests that our case is the youngest ever reported. In conclusion, although BHT is considered benign, clinical, haematological and histological, evaluation is recommended to exclude several entities which can present as pigmented lesions of the oral mucosa.

Tongue discoloration in an elderly kidney transplant recipient: Treatment-related adverse event?

BACKGROUND

With the increased occurrence of methicillin-resistant staphylococcus aureus infections, linezolid treatment might be administered more often. New rare adverse events are likely to follow.

CASE SUMMARY

A 65-year-old man (weight, 91 kg; height, 185 cm) presented to the emergency department at the University of Virginia-affiliated Salem Veterans Affairs Medical Center, Salem, Virginia, after a recent (8 weeks) kidney transplantation with a 24-hour history of fatigue, chills, arthralgias, increased urinary frequency, and onset of tongue discoloration. Two days before admission, he completed a 14-day course of linezolid 600 mg PO BID for ampicillin-resistant enterococcal urinary tract infection. He was afebrile on admission and the dorsal aspect of his tongue was blackened centrally, browner peripherally, with normal pink mucosa on the periphery. Based on the Naranjo probability scale, the calculated score for tongue discoloration as a drug-related adverse event was 7 out of a maximum score of 13 points, designating it as a probable cause. The patient's tongue discoloration improved moderately during the hospital stay and resolved 6 months after the discontinuation of linezolid.

CONCLUSIONS

We report a rare association of linezolid and tongue discoloration in an elderly kidney transplant recipient that improved with discontinuation. We present this case to increase clinicians' awareness of the potential adverse event.

Dermoscopic patterns of the filiform papillae of the tongue in patients with Sjogren's syndrome

The purpose of this study was to determine whether there are any differences in the appearance of tongue-surface structure in different kinds of collagen diseases, because red tongue is well known to be a very important feature of suspected Sjögren's syndrome (Sjs). To clarify some features of the filiform papillae on the dorsal surfaces of the tongues of patients with speculated Sjs, we observed a total of 565 individuals with primary Sjs (n = 24, M/F = 0/24), secondary Sjs (n = 16, M/F = 1/15), possible Sjs (n = 96, M/F = 21/75), collagen diseases (CD) (n = 55, M/F = 15/40; 15 SSc, 10 SLE 10, two MCTD, six dermatomyositis, and 22 others), various cutaneous disorders (n = 324, M/F = 118/206), and healthy controls (HC) (n = 50, M/F = 32/18) by using a dermoscope. The average ages of the patients with Sjs, CD (non-Sjs), cutaneous disorders (non-Sjs/CD), and HC were 56.4 14.8, 55.1 116.4, 51.1 121.2, and 37.1 110.6 years of age, respectively. The filiform papillae were classified into four patterns by their structural characteristics: normal papillae (no abnormality with clear cornified tips) (pattern I, n = 162), slightly rounded papillae with unclear cornified tips (pattern II, n = 239), rounded papillae without cornified tips (pattern III, n = 86), and completely flattened papillae (pattern IV, n = 28). Their patterns were reversely related to the volume of salivary fluid (gum test) (P = 0.046) and the degree of furor coating of the tongue (P = 0.051). Pattern IV is predominant in definitive Sjs (primary and secondary Sjs) (n = 15; 53.6%) with positive anti-SS-A or -B antibody (n = 8) with a specificity of 53.6% and a sensitivity of 36.6%. The present dermoscopic finding that the completely flattened pattern (IV) is predominant in definite Sjs patients may indicate a useful marker for suspicion of Sjs.

A two-stage, p16(INK4A)- and p53-dependent keratinocyte senescence mechanism that limits replicative potential independent of telomere status

With increasing frequency during serial passage in culture, primary human keratinocytes express p16(INK4A) (p16) and undergo senescence arrest. Keratinocytes engineered to express hTERT maintain long telomeres but typically are not immortalized unless, by mutation or other heritable event, they avoid or greatly reduce p16 expression. We have confirmed that keratinocytes undergo p16-related senescence during growth in culture, whether in the fibroblast feeder cell system or in the specialized K-sfm medium formulation, and that this mechanism can act as a barrier to immortalization following hTERT expression. We have characterized the p16-related arrest mechanism more precisely by interfering specifically with several regulators of cell cycle control. Epidermal, oral mucosal, corneal limbal, and conjunctival keratinocytes were transduced to express a p16-insensitive mutant cdk4 (cdk4(R24C)), to abolish p16 control, and/or a dominant negative mutant p53 (p53DD), to abolish p53 function. Expression of either cdk4(R24C) or p53DD alone had little effect on life span, but expression of both permitted cells to divide 25 to 43 population doublings (PD) beyond their normal limit. Keratinocytes from a p16(+/-) individual transduced to express p53DD alone displayed a 31-PD life span extension associated with selective growth of variants that had lost the wild-type p16 allele. Cells in which both p53 and p16 were nonfunctional divided rapidly during their extended life span but experienced telomere erosion and ultimately ceased growth with very short telomeres. Expression of hTERT in these cells immortalized them. Keratinocytes engineered to express cdk4(R24C) and hTERT but not p53DD did not exhibit an extended life span. Rare immortal variants exhibiting p53 pathway defects arose from them, however, indicating that the p53-dependent component of keratinocyte senescence is telomere independent. Mutational loss of p16 and p53 has been found to be a frequent early event in the development of squamous cell carcinoma. Our results suggest that such mutations endow keratinocytes with extended replicative potential which may serve to increase the probability of neoplastic progression.

Human keratinocytes that express hTERT and also bypass a p16(INK4a)-enforced mechanism that limits life span become immortal yet retain normal growth and differentiation characteristics

Normal human cells exhibit a limited replicative life span in culture, eventually arresting growth by a process termed senescence. Progressive telomere shortening appears to trigger senescence in normal human fibroblasts and retinal pigment epithelial cells, as ectopic expression of the telomerase catalytic subunit, hTERT, immortalizes these cell types directly. Telomerase expression alone is insufficient to enable certain other cell types to evade senescence, however. Such cells, including keratinocytes and mammary epithelial cells, appear to require loss of the pRB/p16(INK4a) cell cycle control mechanism in addition to hTERT expression to achieve immortality. To investigate the relationships among telomerase activity, cell cycle control, senescence, and differentiation, we expressed hTERT in two epithelial cell types, keratinocytes and mesothelial cells, and determined the effect on proliferation potential and on the function of cell-type-specific growth control and differentiation systems. Ectopic hTERT expression immortalized normal mesothelial cells and a premalignant, p16(INK4a)-negative keratinocyte line. In contrast, when four keratinocyte strains cultured from normal tissue were transduced to express hTERT, they were incompletely rescued from senescence. After reaching the population doubling limit of their parent cell strains, hTERT(+) keratinocytes entered a slow growth phase of indefinite length, from which rare, rapidly dividing immortal cells emerged. These immortal cell lines frequently had sustained deletions of the CDK2NA/INK4A locus or otherwise were deficient in p16(INK4a) expression. They nevertheless typically retained other keratinocyte growth controls and differentiated normally in culture and in xenografts. Thus, keratinocyte replicative potential is limited by a p16(INK4a)-dependent mechanism, the activation of which can occur independent of telomere length. Abrogation of this mechanism together with telomerase expression immortalizes keratinocytes without affecting other major growth control or differentiation systems.