Minocycline-Induced Scleral and Dermal Hyperpigmentation

A review of the application of in-vivo confocal microscopy on conjunctival diseases

Over the past few decades, the expanded applications of in-vivo confocal microscopy (IVCM) have greatly enhanced the knowledge of a variety of conjunctival diseases. IVCM allows non-invasively detailed observation of tarsal, palpebral and bulbar conjunctiva, from the superficial to the substantia propria at the cellular level. IVCM has been shown as a powerful tool for the assessment of morphological changes in both physiological and pathological conditions. High-resolution images of different cellular phenotypes, together with quantifiable results, open new insights into understanding the mechanisms of conjunctival diseases, as well as provide valuable and longitudinal information for the diagnosis and therapeutic evaluation. This review aims to provide an overview of the current knowledge on the applications of IVCM on conjunctival disorders, including aging changes, dry eye-related morphological changes, glaucoma and glaucoma surgery-related morphological changes, conjunctival neoplasm, pterygium, allergic conjunctivitis, trachomatous scarring, and the conjunctiva-associated lymphoid tissue (CALT) changes. In this review, we highlight the key findings of previous studies and discusses the current limitations and challenges of IVCM in assessing the structural characteristics of the conjunctiva. Furthermore, we consider possible future directions for unlocking the full potential of IVCM applications. The insights presented here will contribute to a more comprehensive understanding of the applications of IVCM in conjunctival diseases.

Scleral Discoloration Because of Minocycline Use: A Case Report and Review of the Literature

In this case report, we highlight minocycline-induced scleral hyperpigmentation, combined with ear and fingernail discoloration that developed after over 15 years of use for rosacea in a 78-year-old male with multiple medical comorbidities. Minocycline, a tetracycline antibiotic, is used to treat rosacea and acne as well as some orthopedic infections. It is typically used for extended periods of time; long-term use of minocycline is associated with hyperpigmentation of the sclera, conjunctiva, retina, teeth, skin, subcutaneous fat, oral mucosa, tympanic membrane, and gingiva. This case highlights that hyperpigmentation is more likely to occur in older patients than in younger patients. Scleral hyperpigmentation is not associated with vision loss; however, cosmetic concerns can prompt discontinuation of minocycline. Nonetheless, after cessation, the lesions persist in some patients. Monitoring for hyperpigmentation in patients using minocycline is important, as the hyperpigmentation is more likely to be permanent with long-term use.

Successful Treatment of Minocycline-Induced Facial Hyperpigmentation with a Combination of Chemical Peels and Intense Pulsed Light

Minocycline is a tetracycline derivative antibiotic commonly used to treat acne, rosacea, and other inflammatory skin conditions. Taking minocycline risks inducing skin pigmentation. If minocycline-induced hyperpigmentation is not treated, it may take months to years for the symptoms to subside after discontinuation of the drug, or the hyperpigmentation may never disappear completely, which can lead to cosmetic anxiety and affect people's quality of life. Previous treatment options for hyperpigmentation were mainly q-switched nd: YAG, ruby, and alexandrite lasers. This article reports a case of facial hyperpigmentation caused by minocycline using a combination of chemical peel and intense pulsed light in a patient with eosinophilic cellulitis (Wells syndrome) who was taking oral minocycline. This case suggests combining chemical peel and intense pulsed light is an effective treatment option for minocycline-induced hyperpigmentation.

A Randomized, Controlled Trial of Intense Pulsed Light in combination with Minocycline Hydrochloride for the Treatment of Inflammatory Acne Vulgaris

BACKGROUND

It has been a long-term debate over the concomitant treatment of inflammatory acne vulgaris using Intense Pulsed Light (IPL) and minocycline due to the photosensitivity of minocycline.

OBJECTIVE

We aimed to evaluate the safety and efficiency of IPL combined with minocycline in treating acne vulgaris in a randomized trial.

METHODS

A total of 40 patients were enrolled and randomly assigned into two groups which were either given minocycline (100 mg per day) for 8 weeks with IPL treatments for three times at the weeks of 0, 4, and 8, or the same dosage of minocycline only. The evaluations for inflammatory lesion count, Investigator Global Assessment of Acne (IGA), erythema and purpura indexes were taken before treatment and at the weeks of 4, 8, and 16.

RESULTS

There were significant improvements in inflammatory lesion count, IGA scores, and purpura index in both groups as compared with the baseline at the week of 16 (p < 0.02). The concomitant therapy, but not minocycline only, significantly improved erythema index (p=0.40) at the 16^th week as compared with the baseline. The group with combined treatment showed significantly continuous improvements in inflammatory lesion counts (p < 0.04) and IGA scores (p ≤ 0.02) at the week of 4, 8, and 16 as compared with the group given by minocycline only. No severe adverse effects were observed during the trial.

CONCLUSION

IPL in combination with minocycline shows a better clinical efficacy for treatment of inflammatory acne vulgaris than minocycline alone, and it is safe.

A Review of Systemic Minocycline Side Effects and Topical Minocycline as a Safer Alternative for Treating Acne and Rosacea

Resistance of Cutibacterium acnes to topical antibiotics historically used to treat acne (topical erythromycin and clindamycin and, more recently, topical azithromycin and clarithromycin) has been steadily increasing and new topical antibiotics are needed. Minocycline is a semisynthetic tetracycline-derived antibiotic currently used systemically to treat a wide range of infections caused by Gram-negative and Gram-positive bacteria. In addition to its antibiotic activity, minocycline possesses anti-inflammatory properties, such as the downregulation of proinflammatory cytokine production, suppression of neutrophil chemotaxis, activation of superoxide dismutase, and inhibition of phagocytosis, among others. These characteristics make minocycline a valuable agent for treatment of dermatological diseases such as acne vulgaris and papulopustular rosacea. However, more frequent or serious adverse effects have been observed upon the systemic administration of minocycline than with other tetracyclines. Examples of serious adverse effects include hypersensitivity syndrome reaction, drug-induced lupus, idiopathic intracranial hypertension, and other autoimmune syndromes that may cause death. Here, we review adverse effects and drug–drug interactions observed with oral administration of minocycline and contrast this with topical minocycline formulations recently approved or under development for effectively treating dermatological disorders with fewer adverse effects and less drug interaction.

Ocular Side Effects of Systemic Drugs Used in Dermatology

Some systemically used drugs in managing dermatologic disorders have associated severe side effects, of which eye involvement is very significant. There are various mechanisms for these drugs to cause damage to the eye. The damage to the eye can be acute as in Stevens–Johnson syndrome or chronic as with chloroquine and hydroxychloroquine toxicity. Knowledge about these drugs and information about the mechanisms and types of damage to the eye are essential. It is also important to understand the monitoring mechanisms to diagnose early and limit the damage. Newer investigative tools, especially the imaging techniques help us to diagnose the adverse effects at an early stage. All these issues are discussed in brief here.