Minocycline-induced autoimmune syndromes: an overview

Use of Doxycycline in a Patient following Minocycline-Induced Lupus

Minocycline, a tetracycline antibiotic, is commonly used to treat rosacea and acne vulgaris. A rare adverse reaction of minocycline use is the development of drug-induced lupus. Fortunately, most patients recover from minocycline-induced lupus (MIL) after the drug is discontinued. However, many patients, after recovering from MIL, may desire further treatment for their acne and may consider doxycycline, a close relative of minocycline. Though no cases of doxycycline-induced lupus have been reported, there is little guidance in the medical literature as to whether doxycycline poses a particular risk to patients who have recovered from MIL. We report the long-term follow-up of a patient who recovered from MIL (the diagnosis satisfying clinical and laboratory criteria) and was treated for 8 years with various forms of doxycycline without any untoward effects, suggesting that, at least in some cases, doxycycline can be used safely following MIL.

Remission of Angiographically Confirmed Minocycline-induced Renal Polyarteritis Nodosa: A Case Report and Literature Review

A 23-year-old man presented with severe hypertension. Based on his history of minocycline treatment for over three years and clinical symptoms, such as myalgias and renovascular hypertension with multiple intrarenal aneurysms, he was diagnosed with minocycline-induced renal polyarteritis nodosa (PAN). After minocycline treatment cessation and management of the hypertension, his blood pressure, renin-aldosterone levels, and urinary protein levels gradually improved. Seven and a half years later, repeated angiography found that the aneurysms had resolved. This is the first report in English describing a case of minocycline-induced renal PAN that was reversed functionally and morphologically without steroids or immunosuppressive drugs.

Pediatric Autoimmune Liver Diseases: Autoimmune Hepatitis and Primary Sclerosing Cholangitis

In chronic hepatitis, a broad differential diagnosis should be considered to accurately identify the cause(s) of liver injury. Autoimmune liver diseases (autoimmune hepatitis, primary sclerosing cholangitis, overlap syndrome) can occur in the setting of limited symptoms; therefore, a high index of suspicion and appropriate diagnostic workup should be performed. Most children with autoimmune hepatitis achieve sustained remission with medical therapy; however, there are no equivalent therapies for primary sclerosing cholangitis that impact the progression of disease. Research should include biomarker studies to predict histologic remission in autoimmune hepatitis and mechanistic studies to define future treatment targets for primary sclerosing cholangitis.

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.

Minocycline for the management of multiple sclerosis: repositioning potential, opportunities, and challenges

INTRODUCTION

Multiple sclerosis (MS) is a chronic demyelinating inflammatory disorder with variable clinical and pathologic characteristics reflecting multiple underlying pathophysiologic mechanisms. Repositioning of existing drugs for the new indications offers several advantages including significant reduction in the cost and time of drug development and exemption from early phase clinical trials. Minocycline has been reported to exhibit immunomodulation in several pre-clinical and clinical studies through suppression of migratory inflammatory cells, modulation of peripheral immune response, and inhibition of microglial activation within the CNS.

AREAS COVERED

Here, the authors review the repositioning potential of minocycline for the treatment of MS along with appraisal of the evidence obtained from preclinical and clinical research. The authors also discuss the advantages and potential safety concerns related to the use of minocycline for the management of MS.

EXPERT OPINION

Minocycline offers several distinct advantages in terms of well-known safety profile, lower cost of therapy, widespread availability, and being available as an oral formulation. The authors call upon the public and private funders to facilitate well designed and adequately powered randomized clinical trials that can provide conclusive evidence regarding the safety and efficacy of minocycline in patients with MS.

Contribution of HLA-DRB1 * 09: 01 allele to development of minocycline induced antineutrophil cytoplasmic antibody (ANCA)-associated cutaneous vasculitis: report of two cases

We report two cases of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) that developed after long-term oral administration of minocycline and consider the contribution of human leukocyte antigen (HLA)-DRB 1 * 09: 01 allele to its development. Case 1; A 47-year-old man receiving minocycline for palmoplantar pustulosis for 24 months developed fever, arthralgia, and irregular livedo on the bilateral lower legs. Skin biopsy demonstrated vasculitis, while a blood test showed positivity of myeloperoxidase (MPO)-ANCA. Discontinuation of minocycline and oral administration of prednisolone relieved the symptoms promptly. Case 2; A 53-year-old woman developed reddish-brown livedo reticularis with tenderness on the bilateral lower legs after administration of minocycline to treat palmoplantar pustulosis for 24 months. Although skin biopsy did not demonstrate vasculitis, a blood test showed MPO-ANCA positivity. Cessation of minocycline resulted in rapid improvement of the cutaneous lesions and constitutional symptoms. We diagnosed both cases as having Drug-associated ANCA-associated Vasculitis (DAV) caused by minocycline according to the diagnostic criteria proposed by Cluver et al. Further examination revealed the presence of HLA-DRB1 * 09:01 allele in both cases. This allele has been implicated in the genetic background of idiopathic microscopic polyangiitis (MPA) in the Japanese population. Our finding suggests a relationship between the development of MPO-ANCA or DAV caused by minocycline and HLA-DRB1 * 09:01 allele, but will have to confirmed by further studies with larger numbers of patients.

A Case of Diffuse Alveolar Hemorrhage Associated with High-Titer of MPO-ANCA Demonstrating Cytoplasmic Staining Pattern

Diffuse alveolar hemorrhage (DAH) is a life-threatening complication of ANCA-associated vasculitis (AAV) that requires urgent recognition and treatment. A presumptive diagnosis is often rendered without histopathology if concordant positivity of ANCA by indirect immunofluorescence (IIF) and ELISA assays, i.e., P-ANCA+/myeloperoxidase (MPO) Ab+ or C-ANCA+/proteinase-3 (PR3) Ab+, is documented in the context of pulmonary-renal syndrome or rapidly progressive glomerulonephritis. In this respect, the discordance between IIF and ELISA assays poses a diagnostic challenge in the absence of convincing histopathology and involves the risks of delaying the implementation of timely immunosuppressive therapy. Here, we report a 74-year-old woman who developed DAH and was found to have a high titer of MPO-ANCA exhibiting cytoplasmic staining on IIF, i.e., MPO-C-ANCA. The literature suggests that the availability of distinct epitopes on the MPO molecule dictates the perinuclear versus cytoplasmic staining pattern, which potentially explains the discordance between ELISA and IIF assays. Her DAH was controlled in association with seven sessions of plasmapheresis, methylprednisolone 1 gram daily for 3 days followed by 1 mg/kg/day, and rituximab. This case exemplifies the importance of consideration of pretest probability of suspected diagnosis that would realize a plausible interpretation of seemingly inconsistent serological profile and its effective incorporation into the diagnostic reasoning.

Reconsidering the Use of Minocycline in the Preliminary Treatment Regime of Rheumatoid Arthritis

Strong epidemiologic, clinical, and basic science studies have identified a number of factors that may lead to rheumatoid arthritis (RA) onset and progression, particularly involving the complex interplay between genomics, environmental risk factors, the breakdown of immune self-tolerance, and microbiome dysbiosis. A chronic state of inflammation established by infectious agents has long been suspected to set the stage for the development of RA. The purpose of this article is to review the contribution of the gut, lung, and oral microbiomes to the pathogenesis of RA and consider the importance of supplementing the preliminary treatment regime of RA patients with antibiotics, in particular, minocycline. Minocycline has been used in the treatment of RA due to its bacteriostatic, as well as immunomodulatory and anti-inflammatory properties. Ultimately, a short course of antibiotic treatment with minocycline may eliminate pathogenic organisms contributing to the development and progression of RA. 

Tetracycline Allergy

Despite the widespread use of tetracycline antibiotics since the late 1940s, tetracycline hypersensitivity reactions have rarely been described in the literature. A comprehensive PubMed search was performed, including allergic and serious adverse reactions attributed to the tetracyclines class of antibiotics. Of the evaluated tetracycline analogs, minocycline was attributed to the greatest overall number and severity of serious adverse events reported in the literature, with notable reactions primarily reported as respiratory and dermatologic in nature. Reactions to tetracycline have also been well described in the literature, and although dermatologic reactions are typically less severe in comparison with minocycline and doxycycline, various reports of anaphylactic reactions exist. Although doxycycline has been noted to have had the fewest reports of severe allergic reactions, rare descriptions of life-threatening reactions are still reported in the literature. Allergic reactions regarding tetracyclines are rare; however, adverse reaction type, severity, and frequency among different tetracycline analogs is somewhat variable. A consideration of hypersensitivity and adverse reaction incidence should be performed prior to the selection of individual tetracycline entities.

Case Series: Minocycline-Associated Thyroiditis

INTRODUCTION

Minocycline, a member of the tetracycline class of antibiotics, has been associated with benign thyroid pigmentation but reports of thyroid dysfunction are sparse.

METHODS

Cases were selected via an inquiry of the electronic medical records for patients with thyroid dysfunction and the use of a tetracycline antibiotic. Non-autoimmune thyroiditis was defined as abnormally low or suppressed thyroid-stimulating hormone (TSH, <0.3 µIU/mL), elevated free thyroxine or total thyroxine, and undetectable antithyroid antibodies.

RESULTS

Nine cases of thyroiditis without autoimmunity were identified out of 423 reviewed patients. Cases of thyroiditis occurred in adolescents ages 14-17 years who had been taking minocycline for 6 months to 4 years. In all cases, minocycline was prescribed for the treatment of acne. Four of the 9 received treatment for thyrotoxicosis with a β-blocker (in 3 cases) and/or antithyroid drug (in 2 cases). Thyroiditis was symptomatic in all but one individual who presented with painless goiter. All thyroiditis was transient and resolved after a median of 4.5 months (range 2-5 months). In one case, thyroiditis was followed by transient hypothyroidism.

DISCUSSION

Minocycline is known to cause thyroid abnormalities, although it has not been definitively linked to thyroid dysfunction. Here, we report 9 cases of non-autoimmune thyroiditis in adolescents receiving minocycline for acne. We recommend that minocycline exposure be considered in the differential diagnosis for thyroiditis and that patients receiving minocycline be counseled regarding the risk of thyroid dysfunction.

Minocycline-Induced Autoimmune Hepatitis: A Rare But Important Cause of Drug-Induced Autoimmune Hepatitis

Drug-induced autoimmune hepatitis (DIAIH) is an increasingly recognized form of drug-induced liver injury that leads to a condition similar to idiopathic autoimmune hepatitis. A number of drugs have been associated with DIAIH, minocycline is one of the most well characterized. Minocycline is a semisynthetic tetracycline antibiotic used in the treatment of acne vulgaris. Minocycline-induced autoimmune hepatitis presents with serologic and histologic features similar to idiopathic autoimmune hepatitis. However, the natural history and outcomes of these two conditions differ significantly. The majority of patients with minocycline-induced autoimmune hepatitis experience complete resolution of symptoms after withdrawal of the medication. Some patients may require a short course of steroids and rarely use of an immunomodulator to achieve resolution of disease. Recurrence of symptoms is rare and typically only occurs with reintroduction of minocycline. It is important for primary care providers to consider minocycline-induced autoimmune hepatitis when liver injury develops during minocycline therapy.

Drug-Induced Autoimmune Hepatitis in a Patient Treated with Minocycline: A Rare Adverse Effect

Drug-induced autoimmune hepatitis is an acute and potentially severe adverse effect, which has been reported following the long-term use of minocycline. The condition's typical biochemical findings include an elevated antinuclear antibody titer, hypergammaglobulinemia with elevated levels of serum immunoglobulin G, and, sometimes, positive anti-smooth muscle antibodies. Characteristically, transaminase levels are very elevated, while markers of cholestasis and bilirubin levels are mildly increased, and histological features are very similar to those observed in sporadic autoimmune hepatitis. Here, we describe an interesting case of a young female who developed drug-induced autoimmune hepatitis after taking minocycline for the treatment of acne vulgaris.

Peripheral Vasculitic Neuropathy Associated With Minocycline Use

We describe 2 patients presenting with multiplex mononeuritis, associated with skin manifestation, secondary to minocycline-induced vasculitis. One of the cases is associated neither with lupus nor polyarteritis nodosa. An extensive laboratory workup ruled out any possible underlying immunologic disorder. Electrodiagnostic studies were conducted to show axonal neuropathy in patchy and multifocal distribution consistent with multiplex mononeuritis. This diagnosis was confirmed with nerve biopsy. Withdrawing from the offending medication, minocycline, improved the patients' clinical condition and the quantitative serological measures.

Genetic Factors Influencing Drug-Induced Liver Injury: Do They Have a Role in Prevention and Diagnosis?

Purpose of Review

The pathogenesis of DILI is currently unknown; however, research has shown strong genetic associations with some DILIs. This paper describes the variant alleles uncovered by GWAS and discusses their potential role as susceptibility biomarkers.

Recent Findings

An association with HLADRB1*15:01 and amoxicillin/clavulanate DILI has been shown by a number of research groups. The presence of the HLA-B*57:01 allele has been associated with an 81-fold increased risk of flucloxacillin DILI. The HLA-B*35:02 allele has significant association with minocycline DILI.

Summary

With the exception of abacavir for HIV therapy, no other prospective genetic screening tests have met the threshold for clinical application. This is largely because DILI incidence is too low to warrant the cost and effort associated with testing. Perhaps, with the development of personalised medicine, a panel of genes for disease susceptibility, drug efficacy and adverse reactions could be tested once off. This would change the cost-effectiveness paradigm, personalise healthcare and reduce DILI risk by avoiding medications in patients with specific HLA alleles.

Minocycline induced lupus with yellow colored chylous exudative pleural effusion

Ninety years old male was admitted to hospital due to breathlessness. The prominent findings were extensive blue-grey skin pigmentation and large left chylothorax. Drug induced lupus was diagnosed due to either minocycline chronic treatment or no alternative illness to explain his sub-acute disease. Minocycline therapy was stopped with gradual improvement of pleural effusion and skin discoloration. This case is the first presentation of minocycline induced lupus with chylothorax.

Environmental Basis of Autoimmunity

The three common themes that underlie the induction and perpetuation of autoimmunity are genetic predisposition, environmental factors, and immune regulation. Environmental factors have gained much attention for their role in triggering autoimmunity, with increasing evidence of their influence as demonstrated by epidemiological studies, laboratory research, and animal studies. Environmental factors known to trigger and perpetuate autoimmunity include infections, gut microbiota, as well as physical and environmental agents. To address these issues, we will review major potential mechanisms that underlie autoimmunity including molecular mimicry, epitope spreading, bystander activation, polyclonal activation of B and T cells, infections, and autoinflammatory activation of innate immunity. The association of the gut microbiota on autoimmunity will be particularly highlighted by their interaction with pharmaceutical agents that may lead to organ-specific autoimmunity. Nonetheless, and we will emphasize this point, the precise mechanism of environmental influence on disease pathogenesis remains elusive.

Drug-induced lupus: an update

Drug-induced lupus erythematosus (DILE) is a lupus-like illness that has been recognized as an entity under environmentally-induced lupus erythematosus, where other agents such as physical (ultra-violet irradiation), chemical (heavy metals, aromatic amines) and food products (alfalfa sprouts) have been implicated. DILE has been accepted as a side effect of therapy with over 80 drugs since its first description in association with sulfadiazine in 1945. The epidemiology and clinical course of SLE and DILE differ markedly and prognosis is generally favourable in the latter although occasional lifethreatening cases have been reported in the literature. Constant pharmacovigilance is crucial for prompt diagnosis and cessation of offending therapy offers the best outcome. This review discusses the clinical presentation, diagnosis of DILE as well as provides an update on postulated pathogenic mechanisms and an overview of implicated drugs.

Severe and Persistent Thyroid Dysfunction Associated with Tetracycline-Antibiotic Treatment in Youth

Thyroid dysfunction in adolescents treated with minocycline for acne has been previously described as transient effect and/or associated with autoimmune thyroiditis. We report nonimmune-mediated thyroid dysfunction associated with minocycline/doxycycline in 3 adolescents whose clinical courses suggest an adverse effect that may be more common, serious, and persistent than realized previously.

Toward a noncytotoxic glioblastoma therapy: blocking MCP-1 with the MTZ Regimen

To improve the prognosis of glioblastoma, we developed an adjuvant treatment directed to a neglected aspect of glioblastoma growth, the contribution of nonmalignant monocyte lineage cells (MLCs) (monocyte, macrophage, microglia, dendritic cells) that infiltrated a main tumor mass. These nonmalignant cells contribute to glioblastoma growth and tumor homeostasis. MLCs comprise of approximately 10%-30% of glioblastoma by volume. After integration into the tumor mass, these become polarized toward an M2 immunosuppressive, pro-angiogenic phenotype that promotes continued tumor growth. Glioblastoma cells initiate and promote this process by synthesizing 13 kDa MCP-1 that attracts circulating monocytes to the tumor. Infiltrating monocytes, after polarizing toward an M2 phenotype, synthesize more MCP-1, forming an amplification loop. Three noncytotoxic drugs, an antibiotic - minocycline, an antihypertensive drug - telmisartan, and a bisphosphonate - zoledronic acid, have ancillary attributes of MCP-1 synthesis inhibition and could be re-purposed, singly or in combination, to inhibit or reverse MLC-mediated immunosuppression, angiogenesis, and other growth-enhancing aspects. Minocycline, telmisartan, and zoledronic acid - the MTZ Regimen - have low-toxicity profiles and could be added to standard radiotherapy and temozolomide. Re-purposing older drugs has advantages of established safety and low drug cost. Four core observations support this approach: 1) malignant glioblastoma cells require a reciprocal trophic relationship with nonmalignant macrophages or microglia to thrive; 2) glioblastoma cells secrete MCP-1 to start the cycle, attracting MLCs, which subsequently also secrete MCP-1 perpetuating the recruitment cycle; 3) increasing cytokine levels in the tumor environment generate further immunosuppression and tumor growth; and 4) MTZ regimen may impede MCP-1-driven processes, thereby interfering with glioblastoma growth.

Safety Considerations and Monitoring in Patients Treated with Systemic Medications for Acne

Acne vulgaris, a disorder of the pilosebaceous unit, is one of the most commonly encountered conditions in dermatology practice. Effective treatment of acne vulgaris is important in that it can prevent psychosocial distress and physical scarring. Systemic therapeutic options are available for moderate to severe acne. It is imperative that the safe and effective treatment revolves around the health care provider's familiarity of side effects of various treatments. In this article, the side effects and monitoring guide for the most commonly prescribed systemic agents for acne vulgaris are reviewed.

Testicular Pain Associated With Minocycline Use

Two males ages 16 and 23 years presented with new testicular pain while taking minocycline. Both patients experienced resolution of their symptoms only after minocycline discontinuation. Testicular pain with minocycline use has been previously described, however only in the setting of systemic autoimmune reactions (which were absent here). These cases represent probable rare adverse reactions to minocycline. For patients taking minocycline who experience otherwise unexplained testicular pain, a trial discontinuation of this medication should be considered.

Vasculitic neuropathy following exposure to minocycline

Objective:

To report 3 patients with minocycline-induced autoimmunity resulting in peripheral nerve vasculitis.

Methods:

We report 3 patients who, during minocycline treatment for acne vulgaris, developed subacute onset of pain and weakness caused by vasculitis in single and multiple mononeuropathy patterns.

Results:

Each patient underwent either a nerve or muscle biopsy that confirmed vasculitis. One patient additionally developed systemic symptoms (including fever, fatigue, and night sweats) and another had a posterior circulation stroke. Symptoms developed with either early or prolonged use of minocycline. Despite withdrawal of minocycline, patients needed long-term immunotherapy to gain neurologic improvement.

Conclusions:

Our findings suggest that the typical neuropathy associated with minocycline use is painful single or multiple mononeuropathy due to peripheral nerve vasculitis, which may also be accompanied by presumed CNS vasculitis (presenting as stroke).

Adverse effects of acne medications: recognition and management

Acne vulgaris is a very common chronic inflammatory disease of the skin. The clinical features of acne range from non-inflammatory comedones to inflammatory nodules. While often perceived as an adolescent disease, the prevalence remains high into adulthood, and the manifestations can have detrimental psychosocial effects. It is therefore not surprising that many patients are motivated to seek treatment. The existing treatment strategies for acne are complex due to the multifactorial pathogenesis of the disease. Although it is difficult to cure, four categories of medications have proved efficacious in reducing acne lesions: topical agents, systemic antibiotics, systemic retinoids, and hormonal agents. Unfortunately, these medications can cause adverse effects that may limit their use. Typically, these adverse effects are mild and transient and can be remedied by altering the dose or frequency of the offending agent. However, more serious adverse effects can occur that pose a significant health risk to the patient. Understanding how to recognize and manage the adverse effects of common acne therapies is imperative to providing the safest and most appropriate treatment for each patient. This article focuses on the recognition and management of adverse effects associated with current acne medications.

Minocycline-induced polyarteritis nodosa-like vasculitis presenting as brainstem stroke

Minocycline use has been associated with the development of autoimmune disorders, including drug-induced vasculitis. Previously published reports suggest that clinical manifestations are limited to cutaneous, constitutional, or musculoskeletal symptoms. To our knowledge there has been only one reported patient with ischemic stroke in the setting of minocycline-induced vasculitis. We describe a 26-year-old woman, with no vascular risk factors, who had an ischemic pontine stroke in the setting of biopsy-proven minocycline-induced polyarteritis nodosa-like vasculitis. Discontinuation of minocycline resulted in resolution of the vasculitis, and she has not had any recurrent ischemic events. This report shows that ischemic strokes may occur as a result of minocycline-induced vasculitis. While this is likely a rare association, recognition is important given the widespread use of minocycline and the potential for devastating consequences in a young population. Consequently, drug-induced vasculitis should be considered in patients with an ischemic stroke taking minocycline.

Effective combination of human bone marrow mesenchymal stem cells and minocycline in experimental autoimmune encephalomyelitis mice

INTRODUCTION

Multiple sclerosis (MS) is the most common inflammatory demyelinating disorder of the central nervous system (CNS). Minocycline ameliorates the clinical severity of MS and exhibits antiinflammatory, neuroprotective activities, and good tolerance for long-term use, whereas it is toxic to the CNS. Recently, the immunomodulation and neuroprotection capabilities of human bone marrow mesenchymal stem cells (hBM-MSCs) were shown in experimental autoimmune encephalomyelitis (EAE). In this study, we evaluated whether the combination of hBM-MSCs and a low-dose minocycline could produce beneficial effects in EAE mice.

METHODS

The sensitivity of hBM-MSCs to minocycline was determined by an established cell-viability assay. Minocycline-treated hBM-MSCs were also characterized with flow cytometry by using MSC surface markers and analyzed for their multiple differentiation capacities. EAE was induced in C57BL/6 mice by using immunization with MOG35-55. Immunopathology assays were used to detect the inflammatory cells, demyelination, and neuroprotection. Interferon gamma (IFN-γ)/tumor necrosis factor alpha (TNF-α) and interleukin-4 (IL-4)/interleukin-10 (IL-10), the hallmark cytokines that direct Th1 and Th2 development, were detected with enzyme-linked immunosorbent assay (ELISA). terminal dUTP nick-end labeling (TUNEL) staining was performed to elucidate the cell apoptosis in the spinal cords of EAE mice.

RESULTS

Minocycline did not affect the viability, surface phenotypes, or differentiation capacity of hBM-MSCs, while minocycline affected the viability of astrocytes at a high dose. In vivo efficacy experiments showed that combined treatment, compared to the use of minocycline or hBM-MSCs alone, resulted in a significant reduction in clinical scores, along with attenuation of inflammation, demyelination, and neurodegeneration. Moreover, the combined treatment with hBM-MSCs and minocycline enhanced the immunomodulatory effects, which suppressed proinflammatory cytokines (IFN-γ, TNF-α) and conversely increased anti-inflammatory cytokines (IL-4, IL-10). In addition, TUNEL staining also demonstrated a significant decrease of the number of apoptotic cells in the combined treatment compared with either treatment alone.

CONCLUSIONS

The combination of hBM-MSCs and minocycline provides a novel experimental protocol to enhance the therapeutic effects in MS.

Doxycycline-Induced Cutaneous Inflammation with Systemic Symptoms in a Patient with Acne Vulgaris

Background:

Doxycycline is a commonly prescribed antibiotic for the treatment of acne vulgaris. Often preferred to other tetracyclines due to a safer and milder side-effect profile, doxycycline is more frequently prescribed as a treatment of this common condition.

Objective:

To present a case report of a young patient who developed skin eruptions over the extremities; myalgias; fatigue; swelling involving the face, hands, and feet; headache; and mood changes after 2 years of using doxycycline. She promptly developed similar symptoms after a rechallenge with doxycycline 1 year later.

Results/Conclusion:

This important finding will make practitioners more vigilant to the side effects of this medication despite its current safety profile and regardless of the time that a patient is using it.

Long-lasting effects of minocycline on behavior in young but not adult Fragile X mice

Fragile X Syndrome (FXS) is the most common single-gene inherited form of intellectual disability with behaviors characteristic of autism. People with FXS display childhood seizures, hyperactivity, anxiety, developmental delay, attention deficits, and visual-spatial memory impairment, as well as a propensity for obsessive-compulsive disorder. Several of these aberrant behaviors and FXS-associated synaptic irregularities also occur in "fragile X mental retardation gene" knock-out (Fmr1 KO) mice. We previously reported that minocycline promotes the maturation of dendritic spines - postsynaptic sites for excitatory synapses - in the developing hippocampus of Fmr1 KO mice, which may underlie the beneficial effects of minocycline on anxiolytic behavior in young Fmr1 KO mice. In this study, we compared the effectiveness of minocycline treatment in young and adult Fmr1 KO mice, and determined the dependence of behavioral improvements on short-term versus long-term minocycline administration. We found that 4- and 8-week-long treatments significantly reduced locomotor activity in both young and adult Fmr1 KO mice. Some behavioral improvements persisted in young mice post-treatment, but in adults the beneficial effects were lost soon after minocycline treatment was stopped. We also show, for the first time, that minocycline treatment partially attenuates the number and severity of audiogenic seizures in Fmr1 KO mice. This report provides further evidence that minocycline treatment has immediate and long-lasting benefits on FXS-associated behaviors in the Fmr1 KO mouse model.

ANA (+) ANCA (+) systemic vasculitis associated with the use of minocycline: case-based review

Minocycline is a synthetic tetracycline-derived antibiotic with significant anti-inflammatory properties that may benefit patients with rheumatoid arthritis. Surprisingly, chronic exposure to minocycline can also cause a breach in immunologic tolerance resulting in a variety of autoimmune syndromes such as drug-induced lupus or autoimmune hepatitis. Vasculitis, most commonly resembling cutaneous polyarteritis nodosa, has also been seen in patients taking this drug. Herein, we present a case of biopsy-proven systemic vasculitis presenting as an ANA (+) ANCA (+) polyarteritis nodosa-like syndrome in a male patient who was taking minocycline for his acne for approximately 2 years. Patient initially presented with constitutional symptoms such as profound weight loss and fatigue, along with myalgias, oligoarticular arthritis, and livedo reticularis. About 2 months later, he developed a severe left testicular pain. Biopsy showed vasculitis complicated with the infarction of the left testis. Angiography revealed microaneurysms in the renal and splenic circulation. Stopping the offending drug, along with the short course of prednisone and hydroxychloroquine, resulted in prompt resolution of his symptoms. We additionally present a comprehensive review of biopsy-proven cases of vasculitis associated with chronic minocycline treatment focusing on its pathogenesis and clinical manifestations.

SAPHO syndrome

SAPHO syndrome is a disorder characterized by Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis. As the osteoarticular and skin manifestations often do not occur simultaneously and there are no validated diagnostic criteria, the diagnosis can be difficult. Clinical and imaging investigation is necessary to establish the many differential diagnoses of SAPHO syndrome. The etiopathogenesis involves infectious (probably Propionibacterium acnes), immunologic, and genetic factors. Treatment is based on information gathered from case reports and small series, and is related to specific skin or articular symptoms.

Autoimmune hepatitis induced by nitrofurantoin. The importance of the autoantibodies for an early diagnosis of immune disease

Nitrofurantoin has been in use since 1953 as an effective agent for the prevention of recurrent urinary tract infection. It is associated with a wide range of adverse drug reactions. Chronic active hepatitis has increasingly been observed and many cases have been reported with case fatalities. We present a case of nitrofurantoin induced chronic active hepatitis and briefly review the serology and clinico pathological features of 57 similar cases reported in English literature. The consistent presence of antinuclear antibody, anti smooth muscle antibody, elevated immunoglobulin and pathological feature suggests an immunologic mechanism. Complete recovery is possible in most cases if medication is discontinued in time. Steroids may play a role in management if no improvement occurs despite discontinuation of medication. We suggest all patients who are on prolonged nitrofurantoin therapy be followed up with anti nuclear antibody, anti smooth muscle antibody, serum immunoglobulin and hepatic panel every three months.

Immunotherapies in rheumatologic disorders

Over the past several decades, rheumatology has directed its focus to understanding and countering the immune dysregulation underlying autoimmune diseases with rheumatologic manifestations. Older therapies, effective though poorly understood, are being scrutinized anew and are yielding the immune-modulating mechanisms behind their efficacy. New therapies, the "biologics," are drugs tailored to address specific immune defects and imbalances. This article discusses the current standard and biologic immunotherapies of the rheumatic diseases, correlating our current understanding of their mechanisms with dysfunctions believed to be present in the major autoimmune syndromes, especially rheumatoid arthritis and systemic lupus erythematosus.

Vasculitic neuropathy associated with minocycline use

INTRODUCTION

Minocycline is an antibiotic used for the treatment of acne. It has been associated with several autoimmune syndromes, including drug-induced lupus, autoimmune hepatitis, and vasculitis.

METHOD AND RESULTS

We report a case of a 28-year-old previously healthy woman who developed a left sciatic mononeuropathy 2 weeks after starting minocycline for acne. Magnetic resonance imaging studies supported the localization. A biopsy of the left sural nerve revealed acute nerve large arteriole necrotizing vasculitis. Her condition improved after the withdrawal of minocycline and a course of treatment with methylprednisolone.

CONCLUSION

This case provides further evidence that minocycline may induce a nonsystemic necrotizing vasculitis.

Drug-induced autoimmune-like hepatitis

The clinical phenotype of classical autoimmune hepatitis can be mimicked by idiosyncratic drug-induced liver injury, and differentiation can be difficult. The goals of this review are to enumerate the major agents of drug-induced autoimmune-like hepatitis, describe the clinical findings and risk factors associated with it, detail the clinical tools by which to assess causality, discuss putative pathogenic mechanisms, and describe treatment and outcome. The frequency of drug-induced autoimmune-like hepatitis among patients with classical features of autoimmune hepatitis is 9%. Minocycline and nitrofurantoin are implicated in 90% of cases. Female predominance, acute onset, and absence of cirrhosis at presentation are important clinical manifestations. Genetic factors affecting phase I and phase II transformations of the drug, polymorphisms that protect against cellular oxidative stress, and human leukocyte antigens that modulate the immune response may be important pathogenic components. Clinical judgment is the mainstay of diagnosis as structured diagnostic methods for drug-induced liver injury are imperfect. The covalent binding of a reactive drug metabolite to a hepatocyte surface protein (commonly a phase I or phase II enzyme), formation of a neoantigen, activation of CD8 T lymphocytes with nonselective antigen receptors, and deficient immune regulatory mechanisms are the main bases for a transient loss of self-tolerance. Discontinuation of the offending drug is the essential treatment. Spontaneous improvement usually ensues within 1 month. Corticosteroid therapy is warranted for symptomatic severe disease, and it is almost invariably effective. Relapse after corticosteroid withdrawal probably does not occur, and its absence distinguishes drug-induced disease from classical autoimmune hepatitis.

Minocycline in acne vulgaris: benefits and risks

Minocycline is a semi-synthetic, second-generation tetracycline. It was introduced in 1972 and has both antibacterial and anti-inflammatory properties. Minocycline is used for a variety of infectious diseases and in acne. Even today, new indications beyond the antibacterial indications are being investigated such as its use in neurologic diseases. Formerly, minocycline was thought to have a superior efficacy in the treatment of inflammatory acne, especially with respect to antibacterial-resistant Propionibacterium acnes. A thorough review of the literature, however, shows that minocycline is not more effective in acne than other tetracyclines. Compared with first-generation tetracyclines, minocycline has a better pharmacokinetic profile, and compared with doxycycline it is not phototoxic. However, minocycline has an increased risk of severe adverse effects compared with other tetracyclines. It may induce hypersensitivity reactions affecting the liver, lung, kidneys, or multiple organs (Drug Reaction with Eosinophilia and Systemic Symptoms [DRESS] syndrome) in the first weeks of treatment and, with long-term treatment, may cause autoimmune reactions (systemic lupus erythematosus, autoimmune hepatitis). In addition, CNS symptoms, such as dizziness, are more frequent compared with other tetracyclines. Long-term treatment may induce hyperpigmentation of the skin or other organs. Resistance of P. acnes to minocycline also occurs, dependent on the prescribing behavior. Considering the aspects of efficacy, its adverse effect profile, resistance, price, and alternatives, minocycline is no longer considered the first-line antibacterial in the treatment of acne.

[Case of minocycline-induced vasculitic neuropathy]

A 70-year-old woman was admitted to our hospital because of fever, numbness in her extremities and right drop foot. Because her hip prosthesis had loosened as a result of infection, she had been taking 100 mg of minocycline orally for eight months. Three months before admission, she had had melena several times and body weight loss and pyrexia developed. A month before admission, asymmetrical paresthesia and numbness appeared in her extremities and finally right drop foot developed. Laboratory tests showed elevated C-reactive protein and positive anti-nuclear antibody. Abnormalities found in nerve conduction study were compatible with mononeuritis multiplex. Sural nerve biopsy revealed an occluded medium-size artery in the epineurium and axonal degeneration in the nerve fascicles, confirming the diagnosis of vasculitic neuropathy. These manifestations met the American Congress Rheumatology criteria for polyarteritis nodosa. However, her clinical conditions markedly improved after discontinuing minocycline and therefore she was diagnosed as having minocycline-induced vasculitic neuropathy. Although minocycline-induced vasculitis is a well known adverse effect of the drug, peripheral neuropathy with biopsy findings has rarely been reported. Drug induced-vasculitis is important as a differential diagnosis for mononeuritis multiplex because the symptoms can be improved by the discontinuation of an offending drug.

Minocycline-induced dermatomyositis

Minocycline is a semisynthetic tetracycline that causes a spectrum of autoimmune adverse reactions. We report a previously healthy patient who developed a panniculitis and histopathologically proven dermatomyositis during treatment with minocycline for acne vulgaris. Her signs and symptoms resolved completely upon cessation of minocycline. This case illustrates a novel adverse effect of a widely prescribed medication.

Lupus syndrome with neutropenia following minocycline therapy - a case report

An 18-year-old patient is described who presented with febrile neutropenia and hepatitis caused by minocycline therapy. This rare complication of minocycline-induced lupus syndrome is discussed here.

Minocycline--an old drug for a new century: emphasis on methicillin-resistant Staphylococcus aureus (MRSA) and Acinetobacter baumannii

The epidemiology of nosocomial and community-acquired infections has changed in recent years. Methicillin-resistant Staphylococcus aureus (MRSA), especially community-associated MRSA (CA-MRSA), has emerged as a gram-positive organism with an increasing impact in clinical practice. Infections with Acinetobacter baumannii have become a major cause of morbidity and mortality. Minocycline has significant in vitro activity against MRSA and A. baumannii that is comparable with agents currently used against these organisms. The absence of an intravenous (i.v.) minocycline formulation in recent years has limited its use in seriously ill patients infected with these organisms. However, minocycline i.v. has recently been reintroduced to the US market. The objective of this study was to review available information on the chemistry, mechanism of action, in vitro activity, resistance mechanisms, pharmacokinetics, tolerability and efficacy of minocycline against MRSA and A. baumannii. This article provides suggestions for future studies and potential uses of minocycline and is designed to trigger interest in systematic clinical evaluation of minocycline for patients infected with these organisms. In conclusion, minocycline is an old drug that has the potential to become an important part of the armamentarium against emerging infections such as CA-MRSA and A. baumannii. Owing to its promising profile against these clinically important pathogens as well as excellent pharmacokinetic properties, minocycline merits evaluation in serious infections.

Immune-mediated adverse drug reactions

Many adverse drug reactions are mediated by the immune system. This can be because the therapeutic effect of the drug targets the immune system. For example, immunosuppressive drugs increase the risk of infections. It is paradoxical that some immunosuppressive drugs can lead to autoimmune reactions. Another mechanism by which drugs can cause an adverse reaction involves an idiosyncratic response to the drug such as an immune-mediated skin rash. These idiosyncratic drug reactions (IDRs) are difficult to study because of the paucity of valid animal models and their unpredictable nature. Therefore, much of our mechanistic knowledge of IDRs is based on inferences from the clinical characteristics of IDRs rather than on controlled mechanistic studies. In general, IDRs are associated with a delay between starting the drug and the onset of the adverse reaction, and the typical delay is different for different types of IDRs. In contrast, on rechallenge, there is usually a rapid onset of the adverse reaction, which is characteristic of an amnestic immune response. The absence of such a rapid response is usually considered evidence that an IDR is not immune-mediated; yet, there are immune-mediated IDRs that do not have an amnestic response. One possible reason for the lack of an amnestic response is if the IDR has a strong autoimmune component leading to deletion of autoimmune memory cells when the drug is withdrawn. Another interesting characteristic of IDRs is that there are many drugs that can cause different types of IDRs in different patients. A possible explanation is that although the immune response is induced by a drug, it is directed against an autoantigen, and interindividual differences in the immune repertoire determine which autoantigen and target organ are affected. Although testing these hypotheses represents a difficult challenge, the importance of these adverse reactions makes it a high priority.