Minocycline-induced intraoral pharmacogenic pigmentation: case reports and review of the literature

Long-Term Safety Profiles of Macrolides and Tetracyclines: A Systematic Review and Meta-Analysis

Macrolides and tetracyclines are antibiotics that have a range of anti-inflammatory properties beyond their microbial capabilities. Although these antibiotics have been in widespread use, the long-term safety profiles are limited. We performed a systematic review and meta-analysis of randomized clinical trials that compared macrolides or tetracyclines with placeboes to provide long-term safety information. We searched Medline and EMBASE from inception to October 2022 and identified studies that reported study drug-related death, serious adverse events (SAEs), or withdrawal rates, and common adverse effects of each drug. Relative risk (RR) and number needed to harm were calculated. Of the 52 randomized clinical trials included, there are 3151 participants on doxycycline, 2519 participants on minocycline, 3049 participants on azithromycin, 763 participants on clarithromycin, 262 participants on erythromycin, and 100 participants on roxithromycin. There was no death related to any study drugs and rates of SAE were not significantly different from placebo in any drug. Overall withdrawal rates were slightly higher than placebo in doxycycline (RR, 1.30; 95% CI, 1.12-1.52) and minocycline (RR, 1.29; 95% CI, 1.15-1.46). Withdrawal rates due to adverse events were higher in doxycycline (RR, 2.82; 95% CI, 1.88-4.22), minocycline (RR, 1.48; 95% CI, 1.09-1.98), and azithromycin (RR, 1.53; 95% CI, 1.13-2.08). Gastrointestinal disturbances are the most common tolerable adverse effects for every drug. Photosensitivity and rash are the second most common adverse effects for doxycycline and minocycline. We found no evidence that long-term use up to 2 years of macrolides or tetracyclines was associated with increased risk of SAEs.

Tetracyclines and bone: Unclear actions with potentially lasting effects

Tetracyclines are a broad-spectrum class of antibiotics that have unclear actions with potentially lasting effects on bone metabolism. Initially isolated from Streptomyces, tetracycline proved to be an effective treatment for Gram +/- infections. The emergence of resistant bacterial strains commanded the development of later generation agents, including minocycline, doxycycline, tigecycline, sarecycline, omadacycline, and eravacycline. In 1957, it was realized that tetracyclines act as bone fluorochrome labels due to their high affinity for the bone mineral matrix. Over the course of the next decade, researchers discerned that these compounds are retained in the bone matrix at high levels after the termination of antibiotic therapy. Studies during this period provided evidence that tetracyclines could disrupt prenatal and early postnatal skeletal development. Currently, tetracyclines are most commonly prescribed as a long-term systemic therapy for the treatment of acne in healthy adolescents and young adults. Surprisingly, the impact of tetracyclines on physiologic bone modeling/remodeling is largely unknown. This article provides an overview of the pharmacology of tetracycline drugs, summarizes current knowledge about the impact of these agents on skeletal development and homeostasis, and reviews prior work targeting tetracyclines' effects on bone cell physiology. The need for future research to elucidate unclear effects of tetracyclines on the skeleton is addressed, including drug retention/release mechanisms from the bone matrix, signaling mechanisms at bone cells, the impact of newer third generation tetracycline antibiotics, and the role of the gut-bone axis.

Minocycline-induced black bone disease with synovial pigmentation in a patient undergoing revision anterior cruciate ligament surgery: A case report

INTRODUCTION

Long-term use of minocycline at high doses is associated with hyperpigmentation with multiple sites of involvement. While the cutaneous organs and the oral cavity are most commonly affected, bone discoloration is a rare entity.

CASE PRESENTATION

A 19-year-old male patient with a history of acne vulgaris and intermittent treatment with high dose minocycline for three years presented with recurrent anterior cruciate ligament (ACL) tear. During arthroscopic surgery, however, hyperpigmentation of the femur and synovium was observed. Abnormal tissue was biopsied and confirmed through histopathological examination to contain melanin-related minocycline pigmentation. Revision surgery was re-scheduled with no intraoperative complications and excellent long-term clinical outcomes.

CLINICAL DISCUSSION

There are several possible causes of hyperpigmentation, including hemosiderin deposition, infection, aseptic necrosis, demineralization, and metastatic disease. Black bone disease, caused by minocycline-induced hyperpigmentation, is rare. While the appearance is grossly abnormal in black bone disease, there has been no evidence suggesting that tissue integrity is compromised.

CONCLUSION

This case confirms that hyperpigmentation does not affect bone integrity and that surgical procedures can be performed safely. Knowing the adverse effects of minocycline administration could reduce inappropriate postponement of surgical procedures, thereby saving time and resources.

Green Bone: Minocycline-Induced Discoloration of Bone Rarely Reported in Foot and Ankle

The tetracycline antibiotics incorporate into bone similar to bisphosphonates. Tetracycline stains bone a fluorescent yellow and minocycline, more commonly used for chronic acne, stains bone dark green. Owing to its frequent use, the occurrence of green bone discoloration due to antibiotics in the tetracycline class is well understood. Its pigmentation can be seen through delicate, thin tissue as a dark blue-gray. Histologic inspection of this bone will confirm a benign condition without evidence of bone disease. Although yellow and green discoloration has been documented frequently in association with oral surgery, it has been reported less commonly in the lower extremity. Green discoloration of bone has rarely been reported in the foot and ankle. Unlike other forms of hyperpigmentation of the skin and bone, this entity is benign when resulting from tetracycline therapy. It is always prudent to have a clinical correlate for an unusual discoloration or hyperpigmentation of any tissue when it exists. In the absence of a definitive clinical correlation, a biopsy is warranted. The following case studies provide a pictoral of green bone as it was encountered in the foot and ankle of 2 young adult females undergoing surgery.

Adverse Drug Reactions in the Orofacial Region

A wide spectrum of drugs can sometimes give rise to numerous adverse orofacial manifestations, particularly dry mouth, taste disturbances, oral mucosal ulceration, and/or gingival swelling. There are few relevant randomized double-blind controlled studies in this field, and therefore this paper reviews the data from case reports, small series, and non-peer-reviewed reports of adverse drug reactions affecting the orofacial region (available from a MEDLINE search to April, 2003). The more common and significant adverse orofacial consequences of drug therapy are discussed.

Black bone disease in a healing fracture

Black bone disease refers to the hyperpigmentation of bone secondary to prolonged usage of minocycline. We present a report of a 34-year-old man who underwent femoral shaft fracture fixation complicated by deep infection requiring debridement. The implants were removed 10 months later after long-term treatment with minocycline and fracture union. A refracture of the femoral shaft occurred 2 days after implant removal and repeat fixation was required. Intraoperatively, abundant heavily pigmented and dark brown bone callus was noted over the old fracture site. There was no evidence of other bony pathology and the appearance was consistent with minocycline-associated pigmentation. As far as we are aware, this is the first case of black bone disease affecting callus within the interval period of bone healing. We also discuss the relevant literature on black bone disease to bring light on this rare entity that is an unwelcomed surprise to operating orthopaedic surgeons.

Diagnosis of oral pigmentations and malignant transformations

BACKGROUND

Oral pigmentation is a common finding in the mouth. Pigmentation can be either normal or abnormal discoloration of oral mucous membrane. The purpose of this review mainly focuses on the main oral pigmented lesions, in order to help the clinicians establish a better approach towards the patients with pigmented oral lesions and to provide thorough knowledge regarding such lesions for patient reassurance, early definitive diagnosis and prompt treatment.

METHODS

Relevant data concerning oral pigmented lesions, clinical features and the possibility of malignant transformation of such lesions were reviewed thoroughly from pubmed literature published in English. Pigmented lesions affecting the skin were not included in our review.

RESULTS

Few pigmented lesions have been identified and their tendency to become malignant has been reported in the literature. The oral lesions showing malignant transformation reported were mostly case series. Unfortunately, due to lack of long-term studies, follow ups and randomized controlled studies in this respect it was difficult to draw a statistical analysis. This information is quite crucial for general dental practitioners to improve their understanding regarding oral lesions and to differentiate between normal and diseased conditions, so that they can master the skill of differential diagnosis, definitive diagnosis and prompt treatment.

CONCLUSION

Oral pigmentation may present as focal, multifocal or diffused macular or tumefactive lesions. They may greatly vary in color as blue, purple, brown, gray or black depending on the quantity and site of melanin in the tissues [1]. Etiology of pigmentation can be multi factorial. Mostly pigmentation is physiologic but at times it can be a precursor of severe diseases. Lesions may be caused by localized harmless accumulations of melanin, hemosiderin or exogenous metals or they may be a sign of underlying systemic or genetic disease. A few lesions may be associated with life-threatening medical conditions that require immediate intervention. The differential diagnosis for any pigmented lesion is extensive, as it includes examples of endogenous and exogenous pigmentations. Although biopsy is a helpful and necessary aid in the diagnosis of focally pigmented lesions, with diffuse pigmentation lesions require a thorough dental and medical history and laboratory investigations.

Adverse drug events in the oral cavity

Adverse reactions to medications are common and may have a variety of clinical presentations in the oral cavity. Targeted therapies and the new biologic agents have revolutionized the treatment of cancers, autoimmune diseases, and inflammatory and rheumatologic diseases but have also been associated with adverse events in the oral cavity. Some examples include osteonecrosis, seen with not only bisphosphonates but also antiangiogenic agents, and the distinctive ulcers caused by mammalian target of rapamycin inhibitors. As newer therapeutic agents are approved, it is likely that more adverse drug events will be encountered. This review describes the most common clinical presentations of oral mucosal reactions to medications, namely, xerostomia, lichenoid reactions, ulcers, bullous disorders, pigmentation, fibrovascular hyperplasia, white lesions, dysesthesia, osteonecrosis, infection, angioedema, and malignancy. Oral health care providers should be familiar with such events, as they will encounter them in their practice.

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.

Characteristics of hospitalized children infected with macrolide-resistant Mycoplasma pneumoniae

Background

The aim of this study was to clarify retrospectively the characteristics of children hospitalized for respiratory tract infection caused by macrolide-resistant Mycoplasma pneumoniae (M. pneumoniae).

Methods

Children who were hospitalized for respiratory tract infection due to M. pneumoniae were enrolled in this study. The diagnosis of M. pneumoniae infection was made on the grounds of polymerase chain reaction results.

Results

Thirty-three children were hospitalized due to lower respiratory tract infection with M. pneumoniae. Of the 33 children, 31 (median age five years) were identified as being infected with macrolide-resistant M. pneumoniae (A2063G:30, A2064G:1) by sequence analysis. Of the 31 children infected with macrolide-resistant M. pneumoniae, 21 (68%) had received 14- or 15-membered macrolide antibiotics and four (13%) had received minocycline before hospitalization. During hospitalization, minocycline was administered to 16 (52%) of the 31 children infected with macrolide-resistant M. pneumoniae. Of the 20 children infected with macrolide-resistant M. pneumoniae under eight years of age, six (30%) were treated with minocycline during hospitalization. The difference in total febrile days between children receiving minocycline treatment before hospitalization and children not receiving minocycline treatment was three days.

Conclusions

The majority of hospitalized children with respiratory tract infection due to macrolide-resistant M. pneumoniae infection was of preschool age and had received 14- or 15-membered macrolide antibiotics before hospitalization. Because macrolide-resistant M. pneumoniae is widespread in Japan, the administration of minocycline as a second-line antibiotic in children under eight years of age cannot be withheld when clinical symptoms do not improve with macrolide antibiotics.

Triclosan-loaded poly(amido amine) dendrimer for simultaneous treatment and remineralization of human dentine

In order to treat dental caries of damaged dentine, triclosan-loaded carboxyl-terminated poly(amido amine) dendrimer (PAMAM-COOH) is prepared and characterized. While being incubated in artificial saliva, triclosan-loaded PAMAM-COOH formulation can induce in situ remineralization of hydroxyapatite (HA) on etched dentine, and the regenerated HA has a similar crystal structure with natural dentine. It can also release the encapsulated triclosan for a long period. The interesting drug release profiles are controlled by both dendrimer encapsulation capability and the mineralization degree, which are ideal to obtain multifunctional properties of long-term release of anti-bacterial drug for local treatment during the remineralization process. The triclosan-loaded G4-COOH provides a general strategy to cure dental caries and repair damaged dentine at the same time, which forms a potential restorative material for dental repair.

Approaches to the evaluation of lip hyperpigmentation

Hyperpigmentation of the lips is a common condition. It is associated with a wide variety of conditions that include physiologic changes, genodermatoses, inflammatory diseases, endocrinologic disorders, drugs and chemicals, benign and malignant neoplasm, and other non-melanotic conditions. The aim of this article is to provide a clinical approach to hyperpigmented lesions on the lips based on the extent of lesions, the age of onset, and associated systemic involvements. In this review, we present an algorithm to guide the diagnosis of and plan for therapeutic intervention for pigmented lesions of the lips. The algorithm is based on the typical clinical presentation of each entity and should not be taken as an absolute indicator of diagnosis. Although the differences in color can help to differentiate among pigmented lesions, the interpretation of color can be subjective and is influenced by the amount and location of the pigment within the mucosa. The limitations of this review are that some data are based on case reports and small case series that may not reflect true association.

Minocycline-induced periarticular black bones in inflamed joints which underwent arthroplastic reconstruction

Background

Minocycline-induced pigmentation of bone (black bone) is well described in tooth-bearing intra-oral bone, but is less known in periarticular bone in patients who have undergone total joint arthroplasty. On a retrospective basis, we investigated the short-term clinico-radiological results of total joint arthroplasties in which the patient developed minocycline-induced periarticular black bone.

Methods

We found 5 cases (0.08%), in 4 patients, of periarticular bone pigmentation revealed during total joint arthroplasties (2 hips, 2 knees, and 1 ankle) in our series of total joint surgeries (6,548 cases) over a 10-year time period in our 3 institutes. Their mean age was 56 years at surgery. All patients had received long-term minocycline treatment. Mean dosage and duration of minocycline was 160 mg/day and 2.2 years, respectively. Minocycline had been prescribed for reactive arthritis (one), rheumatoid arthritis (two) and late infection after total joint arthroplasty (two patients). Mean follow-up period was 3.4 years after the surgeries.

Results

All cases had black or brown pigmentation in the periarticular bones during the surgery. There was no pigmentation in the cartilage or soft tissues of the joints. The mean Japanese Orthopaedic Association (JOA) score or Japanese Society for Surgery of the Foot (JSSF) scale for rheumatoid arthritis foot and ankle joints at latest follow-up (case 1, 66; case 2, 87; case 3, 77; case 4, 77; case 5, 80) improved compared to those of pre-surgery (case 1, 47; case 2, 45; case 3, 55; case 4, 34; case 5, 55). No implant loosening was noted on radiographic examination during the follow-up period. No abnormal bone formation, bone necrosis, hemosiderin deposition, malignancy or metallic debris was found on histological examination.

Conclusions

No clinico-radiological symptoms of total joint arthroplasties showed in the patients with minocycline-induced periariticular black bone in the short-term. Systemic minocycline treatment has the potential to induce significant black pigmentation of many tissues. In particular, minocycline-induced pigmentation of periarticular bone may be accelerated by inflammation due to rheumatic or pyogenic arthritis. Surgeons should recognize the risk of bone pigmentation in inflamed joints due to the systemic treatment of minocycline and explore its influence on periarticular bone and total joint arthroplasty in the long-term.

Drug-induced black hairy tongue

Black hairy tongue (BHT) is a benign, self-limiting disorder characterized by abnormally hypertrophied and elongated filiform papillae on the surface of the tongue. The prevalence of BHT is quite variable, ranging from 0-53.8% depending on the population. Many predisposing factors to BHT exist, and several drugs and drug classes have been implicated in causing this disorder. A modified Naranjo adverse drug reaction probability nomogram specific for BHT was used to rate causality for the available published case reports of drug-induced BHT. From the available data, antibiotics and drugs capable of inducing xerostomia are the drug classes that have modest evidence of causality and a rational mechanism. The presence of underlying predisposing factors in these cases along with the variable prevalence of BHT make drawing firm conclusions difficult. Treatment for BHT involves eliminating any predisposing issues and practicing scrupulous oral hygiene. Drug therapy and physical removal of the elongated filiform papillae are available for resistant cases. Clinicians should be aware of the prevalence, the predisposing factors and drug classes that may play a role in the development, and the treatment of BHT.

Staining of palatal torus secondary to long term minocycline therapy

Minocycline and other tetracycline analogs are well known to cause discoloring of alveolar bone, teeth and other tissues. The present case reports palatine torus discoloring, in a 91-year-old patient, after long term minocycline therapy. The patient was presented with staining of the palatal torus resulting from prior minocycline use for three-and-a-half years. The diagnosis of minocycline staining of palatal torus was done during a routine hygiene examination. The patient was informed that the bluish appearance of the palatal torus was the result of long term minocycline use. The patient was not willing to discontinue the antibiotic and was not concerned about the appearance. The clinician should inform patients on long term minocycline therapy about the possible side effects of staining of the alveolar bone, teeth and other soft tissue.

Drug-induced disorders of teeth

It is essential that every health care professional who is involved with the prescription or recommendation of drugs be fully aware of any resultant disorders that may arise as a side-effect. A range of drugs can affect the teeth. In this review article, drugs that have the potential to induce changes in teeth have been classified as those leading to tooth discoloration (intrinsic and extrinsic), physical damage to tooth structure (enamel, dentin, and cementum), and alteration in tooth sensitivity.

Minocycline-associated intra-oral soft-tissue pigmentation: clinicopathologic correlations and review

BACKGROUND

Intra-oral minocycline staining of alveolar bone and teeth is well-described in the literature. Minocycline-induced discoloration of oral soft tissues is less common and has been often attributed to staining of the underlying bone.

AIM

This report documents the clinical and histopathologic features of a case of actual oral soft tissue minocycline-induced pigmentation. The patient, a 45-year-old Caucasian female, presented with pigmentation of the gingiva, lips, and nail beds of recent onset. The past medical history revealed initiation of minocycline therapy 6 months earlier for dermatological concerns. Histopathologic examination of biopsy specimens from the gingiva and lip showed evidence of increased melanin/melanocytes in the epithelium and melanin/melanophages in the connective tissue. A working diagnosis of drug-associated pigmentation was determined and the patient discontinued immediately minocycline therapy. Nine months after cessation of minocycline the patient exhibited a marked reduction in pigmentation.

CONCLUSION

Systemic minocycline treatment has the potential to induce significant and esthetically objectionable discoloration of the gingiva and oral mucosa. A brief review of the literature is presented to help understand this uncommon finding that should be included in the differential diagnosis of spontaneous discoloration of intra-oral soft tissues.

Tetracycline and other tetracycline-derivative staining of the teeth and oral cavity

Tetracyclines (TCN) were introduced in 1948 as broad-spectrum antibiotics that may be used in the treatment of many common infections in children and adults. One of the side-effects of tetracyclines is incorporation into tissues that are calcifying at the time of their administration. They have the ability to chelate calcium ions and to be incorporated into teeth, cartilage and bone, resulting in discoloration of both the primary and permanent dentitions. This permanent discoloration varies from yellow or gray to brown depending on the dose or the type of the drug received in relation to body weight. Minocycline hydrochloride, a semisynthetic derivative of tetracycline often used for the treatment of acne, has been shown to cause pigmentation of a variety of tissues including skin, thyroid, nails, sclera, teeth, conjunctiva and bone. Adult-onset tooth discoloration following long-term ingestion of tetracycline and minocycline has also been reported. The remarkable side-effect of minocycline on the oral cavity is the singular occurrence of "black bones", "black or green roots" and blue-gray to gray hue darkening of the crowns of permanent teeth. The prevalence of tetracycline and minocycline staining is 3-6%. The mechanism of minocycline staining is still unknown. Most of the reviewed literature consisted of case reports; longitudinal clinical trials are necessary to provide more information on the prevalence, severity, etiology and clinical presentation of tetracycline and TCN-derivative staining in the adult population.

Black pigmentation of bone due to long-term minocycline use

Minocycline-induced dark pigmentation has been described affecting the oral cavity (teeth, mucosa, alveolar bone), skin, nails, eyes and thyroid. To date, there is no report of other bones being affected. We report a case of black pigmentation of the acromian in a patient who had used minocycline on a long-term basis for acne rosecea. Biopsy of the iliac crest revealed that the pelvis was also affected.

Oral mucosal pigmentation secondary to minocycline therapy: report of two cases and a review of the literature

Minocycline is a semisynthetic broad-spectrum antimicrobial agent that was first introduced into clinical practice in 1967. The most common use of minocycline is for the long-term treatment of acne vulgaris. A well-recognized side effect of minocycline treatment is pigmentation, which has been reported in multiple tissues and fluids including thyroid, skin, nail beds, sclera, bone, and teeth. While there have been several reports of oral pigmentation following minocycline therapy, these have been, for the most part, pigmentation of the underlying bone with the overlying oral mucosa only appearing pigmented. We report two cases of actual pigmented oral mucosal lesions on the hard palate secondary to minocycline therapy with the accompanying histopathology, followed by a discussion of minocycline-induced oral pigmentation and a differential diagnosis of these lesions.

Minocycline: stain devil?

Minocycline is the treatment of choice for acne vulgaris, the most common form of inflammatory acne, despite the increase in awareness of rare but significant side-effects. This paper discusses the undesirable side-effect of minocycline staining in permanent teeth.

Minocycline-induced staining of torus palatinus and alveolar bone

BACKGROUND

Minocycline hydrochloride, an analog of tetracycline, is widely used in the treatment of acne. Its use has been associated with discoloration of teeth, bone, and other tissues.

METHODS

A case is presented involving a patient with minocycline-induced staining of the torus palatinus and alveolar bone.

RESULTS

No treatment was rendered since the patient was not concerned with the appearance of the discoloration. The patient's dermatologist elected to change antibiotics.

CONCLUSIONS

Patients on long-term minocycline therapy should be made aware of the possibility of pigmentation of bone and soft tissue that may be reversible with discontinuation of therapy; however, minocycline-induced staining of the permanent dentition may not be reversible.

[Cyclines and acne: pay attention to adverse drug reactions! A recent literature review]

PURPOSE

Cyclines are broad-spectrum antibiotics often used in acne. Side effects might occur precociously or more insidiously during long term treatment such in acne. The aim of this study is to review all adverse effects recently reported in this indication.

CURRENT KNOWLEDGE AND KEY POINTS

A literature review from 1997 to 2001 has been conducted. Seventy-six articles reporting 250 cases have been found. Data analysis indicated that minocycline is the most widely incriminated molecule. Seventy-two cases revealed autoimmune disorders : lupus like syndrome associated or not with autoimmune hepatitis, 5 cases developed vasculitis. These reactions occurred in long term treatment (several weeks to several months). Fifteen cases of hypersensitivity syndromes and 3 cases of serum sickness like illness have been reported. These reactions occurred within the first weeks of exposure. Twenty-four cases of pseudotumor cerebri and 123 cases of abnormal pigmentations (skin, nails, mouth, bones or organs) have also been found. Eight cases presented other diseases.

FUTURE PROSPECTS AND PROJECTS

Adverse effects of cyclines might be serious and sometimes unknown. Long term treatment by tetracyclines must be researched in patients presenting such symptoms. Moreover, several adverse drug reactions might be avoided by an optimal use of the drug (oesophageal ulcerations, photosensitivity) or by shorter periods of treatment (autoimmune disorders, pigmentations); only DRESS are drug adverse reactions unpredictable and sometimes severe.

Tetracyclines for the treatment of rheumatoid arthritis

In this review the rationale for the possible beneficial effect of tetracycline derivatives for the treatment of rheumatoid arthritis is discussed. Early studies (Sanchez, Skinner et al. and Brown et al. ) and the two open trials of the 1980s are briefly discussed. The three double-blind studies conducted in the 1990s (Kloppenburg et al. , The Netherlands; the MIRA trial, USA and the O'Dell et al., USA) are described in detail. The baseline clinical and demographic data for these patients, as well as the efficacy and toxicity data are described in the text and summarised in tables. The long-term data of the O'Dell et al.'s trial is described. Finally, side effects not observed during the conduct of these trials, but reported to occur in other patients, for example those receiving minocycline for the treatment of acne, are also listed.

Dental and oral discolorations associated with minocycline and other tetracycline analogs

It has been well acknowledged in recent literature that minocycline, a semisynthetic tetracycline derivative, causes discolorations in adult teeth and various other collagenous tissues. This article presents the most common patterns of minocycline staining in addition to comparing the staining patterns of other tetracycline analogs in the permanent dentition. It also reviews the literature's most prominent theories describing the process of minocycline discoloration, and evaluates their plausibility. It is a goal of this article to make dental practitioners aware of the possible effects of minocycline therapy and to highlight useful ways to treat or prevent these discolorations. Currently, conventional treatments include vital and nonvital bleaching, veneers, or crowns, depending on the severity of the discoloration. The literature shows that possible preventive efforts revolve around cessation of the drug or the use of large doses of vitamin C or other antioxidants in conjunction with minocycline therapy to prevent the formation of the pigment responsible for the staining.

CLINICAL SIGNIFICANCE

Minocycline and other tetracycline analogs are well known for causing discoloration of developing teeth in children. However, practitioners must be aware of the tooth staining potential of minocycline in adult populations as well. Studies suggest that the concomitant use of vitamin C may help prevent adult-onset pigmentation caused by minocycline.

Drugs and oral disorders

This chapter affirms that drugs and medicaments may have a profound effect on the periodontal structures. In some instances, such as drug-induced melanosis, the effect may be insignificant to the health of the patient. In other circumstances, drug-induced disorders may initiate painful, destructive disease processes that will not be successfully managed unless the causal role of drugs is recognized and altered. Finally, the clinician must remain aware of the contribution of drug-induced xerostomia and smoking to increased susceptibility to dental and periodontal diseases.

Minocycline-associated tooth staining

OBJECTIVE

To describe a case of tooth discoloration in an adult after minocycline treatment for arthritis.

CASE SUMMARY

A 68-year-old white women presented with blue-black staining of her lower anterior teeth after 4 months of minocycline therapy for arthritis. Her other medications are not known to cause discoloration of teeth. While the patient continued taking minocycline, her dentist was not able to remove the discoloration. Within 1 month after discontinuation of the minocycline, the dentist was able to remove the discoloration entirely.

DISCUSSION

Minocycline, a synthetic derivative of tetracycline, has been shown to cause abnormal pigmentation of the skin, thyroid gland, nails, bone, sclera, and conjunctiva in adults. It also has been shown to cause tooth discoloration in a few patients. This case is unusual in that the tooth discoloration disappeared after discontinuing minocycline therapy.

CONCLUSIONS

This complication of minocycline is more commonly thought of in the pediatric population. However, clinicians need to be aware of this adverse drug reaction, as this agent may be used increasingly in the treatment of adults with arthritis.

Management of gingival vitiligo with the use of a tattoo technique

The purpose of this report is to describe the management of gingival vitiligo in a black female. This patient was referred by her psychiatrist to the Mount Sinai Hospital Dental Department (Toronto) for assessment of progressive loss in gingival pigmentation. According to her psychiatrist this loss of pigmentation, which the patient indicated may be considered in Africa as a hallmark of HIV infection, was a significant exogenous factor in relation to the patient's ongoing clinical depression. After obtaining informed consent, a modification of a tattooing method used for skin was applied to the patient's attached gingival tissues. Test sites were tattooed prior to performing full gingival tattooing under local anaesthesia. The results demonstrate that it was possible to restore this patient's gingival pigmentation in a highly esthetically acceptable manner. The resulting coloration was reminiscent of the patient's natural pigmentation that had been lost ostensibly because of her systemic disorder. Our findings also showed that the artificial pigmentation established via the tattoo method was stable 4 months postoperatively and continues to be stable, as expected. A profound improvement in the patient's mood was noted.