Skin pigmentation from clofazimine therapy in leprosy patients: a reappraisal

Pre-formulation of an additive combination of two antimicrobial agents, clofazimine and nisin A, to boost antimicrobial activity

According to the World Health Organization, antimicrobial resistance is one of the top ten issues that pose a major threat to humanity. The lack of investment by the pharmaceutical industry has meant fewer novel antimicrobial agents are in development, exacerbating the problem. Emerging drug design strategies are exploring the repurposing of existing drugs and the utilization of novel drug candidates, like antimicrobial peptides, to combat drug resistance. This proactive approach is crucial in fighting global health threats. In this study, an additive combination of a repurposed anti-leprosy drug, clofazimine, and an antimicrobial peptide, nisin A, are preformulated using liquid antisolvent precipitation to generate a stable amorphous, ionized nanoparticle system to boost antimicrobial activity. The nanotechnology aims to improve the physicochemical properties of the inherently poorly water-soluble clofazimine molecules while also harnessing the previously unreported additive effect of clofazimine and nisin A. The approach transformed clofazimine into a more water-soluble salt, yielding amorphous nanoparticles stabilized by the antimicrobial peptide; and combined the two drugs into a more soluble and more active formulation. Blending pre-formulation strategies like amorphization, salt formation, and nanosizing to improve the inherent low aqueous solubility of drugs can open many new possibilities for the design of new antimicrobial agents. This fusion of pre-formulation technologies in combination with the multi-hurdle approach of selecting drugs with different effects on microbes could be key in the design platform of new antibiotics in the fight against antimicrobial resistance.

Clofazimine for the treatment of tuberculosis

Shorter (6-9 months), fully oral regimens containing new and repurposed drugs are now the first-choice option for the treatment of drug-resistant tuberculosis (DR-TB). Clofazimine, long used in the treatment of leprosy, is one such repurposed drug that has become a cornerstone of DR-TB treatment and ongoing trials are exploring novel, shorter clofazimine-containing regimens for drug-resistant as well as drug-susceptible tuberculosis. Clofazimine's repurposing was informed by evidence of potent activity against DR-TB strains in vitro and in mice and a treatment-shortening effect in DR-TB patients as part of a multidrug regimen. Clofazimine entered clinical use in the 1950s without the rigorous safety and pharmacokinetic evaluation which is part of modern drug development and current dosing is not evidence-based. Recent studies have begun to characterize clofazimine's exposure-response relationship for safety and efficacy in populations with TB. Despite being better tolerated than some other second-line TB drugs, the extent and impact of adverse effects including skin discolouration and cardiotoxicity are not well understood and together with emergent resistance, may undermine clofazimine use in DR-TB programmes. Furthermore, clofazimine's precise mechanism of action is not well established, as is the genetic basis of clofazimine resistance. In this narrative review, we present an overview of the evidence base underpinning the use and limitations of clofazimine as an antituberculosis drug and discuss advances in the understanding of clofazimine pharmacokinetics, toxicity, and resistance. The unusual pharmacokinetic properties of clofazimine and how these relate to its putative mechanism of action, antituberculosis activity, dosing considerations and adverse effects are highlighted. Finally, we discuss the development of novel riminophenazine analogues as antituberculosis drugs.

Disorders of hyperpigmentation. Part I. Pathogenesis and clinical features of common pigmentary disorders

Disorders of hyperpigmentation are common and, depending on the extent and location of involvement, can affect the quality of life and pose a significant psychologic burden for patients. Given the similarities in presentation of the various causes of hyperpigmentation, it is often difficult to elucidate the etiology of these conditions, which is important to guide management. Furthermore, certain disorders, such as lichen planus pigmentosus and ashy dermatosis, have similar clinical and/or histologic presentations, and their classification as distinct entities has been debated upon, leading to additional confusion. In this review, the authors selected commonly encountered disorders of hyperpigmentation of the skin, subdivided into epidermal, dermal, or mixed epidermal-dermal disorders based on the location of pigment deposition, along with disorders of hyperpigmentation of the mucosa and nails. Melanocytic nevi, genetic disorders, and systemic causes of hyperpigmentation were largely excluded and considered to be outside the scope of this review. We discussed the pathogenesis of hyperpigmentation as well as the clinical and histologic features of these conditions, along with challenges encountered in their diagnosis and classification. The second article in this 2-part continuing medical education series focuses on the medical and procedural treatments of hyperpigmentation.

Measuring Stigma to Assess the Social Justice Implications of Health-Related Policy Decisions: Application to Novel Treatment Regimens for Multidrug-Resistant Tuberculosis

In making policy decisions with constrained resources, an important consideration is the impact of alternative policy options on social justice. Social justice considers interactions between individuals and society and can be conceptualized across domains of agency, association, and respect. Despite its importance, social justice is rarely considered formally in health policy decision making, partially reflecting challenges in its measurement. We define three criteria for considering social justice in health-related policy decisions: 1) linkage of social justice to a measurable construct; 2) ability to reproducibly and feasibly estimate the impacts of a policy decision on the selected construct; and 3) appropriate presentation to decision makers of the expected social justice implications using that construct. We use preliminary data from qualitative interviews from three groups of respondents in South Africa and Uganda to demonstrate that stigma meets the first of these criteria. We then use the example of policy addressing novel treatment regimens for multidrug-resistant tuberculosis and a validated tuberculosis stigma scale to illustrate how policy effects on stigma could be estimated (criterion 2) and presented to decision makers in the form of justice-enhanced cost-effectiveness analysis (criterion 3). Finally, we provide a point-by-point guide for conducting similar assessments to facilitate consideration of social justice in health-related policy decisions. Our case study and guide for how to make social justice impacts more apparent to decision makers also illustrates the importance of local data and local capacity. Performing social justice assessments alongside more traditional evaluations of cost-effectiveness, budget impact, and burden of disease could help represent data-informed considerations of social justice in health care decision making more broadly.

Shortened tuberculosis treatment regimens: what is new?

Given the global burden of tuberculosis, shortened treatment regimens with existing or repurposed drugs are needed to contribute to tuberculosis control. The long duration of treatment of drug-susceptible tuberculosis (DS-TB) is associated with nonadherence and loss to follow up, and the treatment success rate of multidrug-resistant tuberculosis (MDR-TB) is low (approximately 50%) with longer regimens. In this review article, we report recent advances and ongoing clinical trials aimed at shortening regimens for DS-TB and MDR-TB. We discuss the role of high-dose rifampin, as well as that of clofazimine and linezolid in regimens for DS-TB. There are at least 5 ongoing clinical trials and 17 observational studies and clinical trials evaluating shorter regimens for DS-TB and MDR-TB, respectively. We also report the results of observational studies and clinical trials evaluating a standardized nine-month moxifloxacin-based regimen for MDR-TB. Further studies, especially randomized clinical trials, are needed to evaluate regimens including newer drugs, drugs proven to be or highly likely to be efficacious, and all-oral drugs in an effort to eliminate the need for injectable drugs.

In Vitro Efficacies, ADME, and Pharmacokinetic Properties of Phenoxazine Derivatives Active against Mycobacterium tuberculosis

Mycobacterium tuberculosis, the causative agent of tuberculosis, remains a leading infectious killer globally, demanding the urgent development of faster-acting drugs with novel mechanisms of action. Riminophenazines such as clofazimine are clinically efficacious against both drug-susceptible and drug-resistant strains of M. tuberculosis We determined the in vitro anti-M. tuberculosis activities, absorption, distribution, metabolism, and excretion properties, and in vivo mouse pharmacokinetics of a series of structurally related phenoxazines. One of these, PhX1, displayed promising drug-like properties and potent in vitro efficacy, supporting its further investigation in an M. tuberculosis-infected animal model.

Structural variety of clofaziminium salts: effect of the counter-ion on clofaziminium conformation and crystal packing

Clofazimine is a water-insoluble antimycobacterial agent gaining attention as a treatment for multi-drug resistant and extensively drug-resistant tuberculosis. Novel salts of clofazimine are reported with fumaric, succinic, 2,4-dihydroxybenzoic and terephthalic acids and with saccharin. The salt structures were obtained by single-crystal X-ray diffraction. The salts with 2,4-dihydroxybenzoic acid and with saccharin are solvated (methanol and acetonitrile, respectively). The reaction of clofazimine with terephthalic acid led to two salt cocrystals, one solvated and one non-solvated. These new clofaziminium salts are compared with the currently known ones in terms of crystal packing and clofazimine/ium conformation. Clofaziminium hydrogen succinate presents isostructurality with clofaziminium hydrogen malonate, an already described salt. In the structure of clofaziminium terephthalate terephthalic acid salt cocrystal, solvent evaporation leads to packing and hydrogen-bonding modifications. In all the new structures, the clofaziminium conformation is quite well conserved and steric hindrance is observed around the protonated site. Conformational optimization of clofaziminium reveals that this steric-hindrance energy penalty is compensated for by hydrogen-bond interactions with the salt counter-ions.

An overview of new antitubercular drugs, drug candidates, and their targets

The causative agent of tuberculosis (TB), Mycobacterium tuberculosis and more recently totally drug-resistant strains of M. tuberculosis, display unique mechanisms to survive in the host. A four-drug treatment regimen was introduced 40 years ago but the emergence of multidrug-resistance and more recently TDR necessitates the identification of new targets and drugs for the cure of M. tuberculosis infection. The current efforts in the drug development process are insufficient to completely eradicate the TB epidemic. For almost five decades the TB drug development process remained stagnant. The last 10 years have made sudden progress giving some new and highly promising drugs including bedaquiline, delamanid, and pretomanid. Many of the candidates are repurposed compounds, which were developed to treat other infections but later, exhibited anti-TB properties also. Each class of drug has a specific target and a definite mode of action. These targets are either involved in cell wall biosynthesis, protein synthesis, DNA/RNA synthesis, or metabolism. This review discusses recent progress in the discovery of newly developed and Food and Drug Administration approved drugs as well as repurposed drugs, their targets, mode of action, drug-target interactions, and their structure-activity relationship.

Single Crystal FLIM Characterization of Clofazimine Loaded in Silica-Based Mesoporous Materials and Zeolites

Clofazimine (CLZ) is an effective antibiotic used against a wide spectrum of Gram-positive bacteria and leprosy. One of its main drawbacks is its poor solubility in water. Silica based materials are used as drug delivery carriers that can increase the solubility of different hydrophobic drugs. Here, we studied how the properties of the silica framework of the mesoporous materials SBA-15, MCM-41, Al-MCM-41, and zeolites NaX, NaY, and HY affect the loading, stability, and distribution of encapsulated CLZ. Time-correlated single-photon counting (TCSPC) and fluorescence lifetime imaging microscopy (FLIM) experiments show the presence of neutral and protonated CLZ (1.3-3.8 ns) and weakly interacting aggregates (0.4-0.9 ns), along with H- and J-type aggregates (<0.1 ns). For the mesoporous and HY zeolite composites, the relative contribution to the overall emission spectra from H-type aggregates is low (<10%), while for the J-type aggregates it becomes higher (~30%). For NaX and NaY the former increased whereas the latter decreased. Although the CLZ@mesoporous composites show higher loading compared to the CLZ@zeolites ones, the behavior of CLZ is not uniform and its dynamics are more heterogeneous across different single mesoporous particles. These results may have implication in the design of silica-based drug carriers for better loading and release mechanisms of hydrophobic drugs.

In Vitro and In Vivo Activities of the Riminophenazine TBI-166 against Mycobacterium tuberculosis

The riminophenazine agent clofazimine (CFZ) is repurposed as an important component of the new short-course multidrug-resistant tuberculosis regimen and significantly shortens first-line regimen for drug-susceptible tuberculosis in mice. However, CFZ use is hampered by its unwelcome skin discoloration in patients. A new riminophenazine analog, TBI-166, was selected as a potential next-generation antituberculosis riminophenazine following an extensive medicinal chemistry effort. Here, we evaluated the activity of TBI-166 against Mycobacterium tuberculosis and its potential to accumulate and discolor skin. The in vitro activity of TBI-166 against both drug-sensitive and drug-resistant M. tuberculosis is more potent than that of CFZ. Spontaneous mutants resistant to TBI-166 were found at a frequency of 2.3 × 10^-7 in wild strains of M. tuberculosis TBI-166 demonstrates activity at least equivalent to that of CFZ against intracellular M. tuberculosis and in low-dose aerosol infection models of acute and chronic murine tuberculosis. Most importantly, TBI-166 causes less skin discoloration than does CFZ despite its higher tissue accumulation. The efficacy of TBI-166, along with its decreased skin pigmentation, warrants further study and potential clinical use.

Topical Delivery of Artemisone, Clofazimine and Decoquinate Encapsulated in Vesicles and Their In vitro Efficacy Against Mycobacterium tuberculosis

Vesicles are widely investigated as carrier systems for active pharmaceutical ingredients (APIs). For topical delivery, they are especially effective since they create a "depot-effect" thereby concentrating the APIs in the skin. Artemisone, clofazimine and decoquinate were selected as a combination therapy for the topical treatment of cutaneous tuberculosis. Delivering APIs into the skin presents various challenges. However, utilising niosomes, liposomes and transferosomes as carrier systems may circumvent these challenges. Vesicles containing 1% of each of the three selected APIs were prepared using the thin-film hydration method. Isothermal calorimetry, differential scanning calorimetry and hot-stage microscopy indicated no to minimal incompatibility between the APIs and the vesicle components. Encapsulation efficiency was higher than 85% for all vesicle dispersions. Vesicle stability decreased and size increased with an increase in API concentration; and ultimately, niosomes were found the least stable of the different vesicle types. Skin diffusion studies were subsequently conducted for 12 h on black human female skin utilising vertical Franz diffusion cells. Transferosomes and niosomes delivered the highest average concentrations of clofazimine and decoquinate into the skin, whereas artemisone was not detected and no APIs were present in the receptor phase. Finally, efficacy against tuberculosis was tested against the Mycobacterium tuberculosis H37Rv laboratory strain. All the dispersions depicted some activity, surprisingly even the blank vesicles portrayed activity. However, the highest percentage inhibition (52%) against TB was obtained with niosomes containing 1% clofazimine.

Impact of Clofazimine Dosing on Treatment Shortening of the First-Line Regimen in a Mouse Model of Tuberculosis

The antileprosy drug clofazimine was recently repurposed as part of a newly endorsed short-course regimen for multidrug-resistant tuberculosis. It also enables significant treatment shortening when added to the first-line regimen for drug-susceptible tuberculosis in a mouse model. However, clofazimine causes dose- and duration-dependent skin discoloration in patients, and the optimal clofazimine dosing strategy in the context of the first-line regimen is unknown. We utilized a well-established mouse model to systematically address the impacts of duration, dose, and companion drugs on the treatment-shortening activity of clofazimine in the first-line regimen. In all studies, the primary outcome was relapse-free cure (culture-negative lungs) 6 months after stopping treatment, and the secondary outcome was bactericidal activity, i.e., the decline in the lung bacterial burden during treatment. Our findings indicate that clofazimine activity is most potent when coadministered with first-line drugs continuously throughout treatment and that equivalent treatment-shortening results are obtained with half the dose commonly used in mice. However, our studies also suggest that clofazimine at low exposures may have negative impacts on treatment outcomes, an effect that was evident only after the first 3 months of treatment. These data provide a sound evidence base to inform clofazimine dosing strategies to optimize the antituberculosis effect while minimizing skin discoloration. The results also underscore the importance of conducting long-term studies to allow the full evaluation of drugs administered in combination over long durations.

Pigmented Deposits in the Skin

Pigmented deposits can occur in the skin due to many and varied causes. Some of them are systemic conditions accompanied by involvement of internal organs. Others have serious prognostic implications, and early diagnosis can help in the correct and adequate management of the diseases. In addition, some of them are quite innocuous and the correct diagnosis avoids unnecessary treatments. In this article, we review the morphologic features of some of the most common and some of the less usual pigmented deposits in skin other than tattoos.

Old antibiotics for emerging multidrug-resistant/extensively drug-resistant tuberculosis (MDR/XDR-TB)

Recently, multidrug-resistant tuberculosis (MDR-TB) has become a therapeutic challenge. In addition to drug resistance, drug adverse events, intravenous delivery, cost and availability of some antibiotics in low-income countries have led to a look back to old drugs, especially those efficient against closely related organisms such as Mycobacterium leprae. Here we review the available drugs that respect the conditions above and could be upgraded to first-line therapy for treating MDR-TB and extensively drug-resistant tuberculosis (XDR-TB).

Extensively Drug-Resistant Tuberculosis: Report and Literature Review on Two Cases Requiring Prolonged Treatment

BACKGROUND Extensively drug-resistant tuberculosis (XDR-TB) is a global problem due to the high morbidity and mortality it causes. Peru is one of the countries with the highest numbers of cases of XDR-TB, which increase every year. CASE REPORT We present the case of two siblings who developed XDR-TB, underwent surgery twice, and were in individualized treatment for more than 6 years. Finally they achieved remission of symptoms, despite not having standardized treatment schemes during their diagnosis period. CONCLUSIONS Extensively drug-resistant tuberculosis can be cured with a treatment that involves both medical care and patient actions to achieve remission of the disease.

Mode of Action of Clofazimine and Combination Therapy with Benzothiazinones against Mycobacterium tuberculosis

Clofazimine (CZM) is an antileprosy drug that was recently repurposed for treatment of multidrug-resistant tuberculosis. In Mycobacterium tuberculosis, CZM appears to act as a prodrug, which is reduced by NADH dehydrogenase (NDH-2), to release reactive oxygen species upon reoxidation by O2. CZM presumably competes with menaquinone (MK-4), a key cofactor in the mycobacterial electron transfer chain, for its reduction by NDH-2. We studied the effect of MK-4 supplementation on the activity of CZM against M. tuberculosis and found direct competition between CZM and MK-4 for the cidal effect of CZM, against nonreplicating and actively growing bacteria, as MK-4 supplementation blocked the drug's activity against nonreplicating bacteria. We demonstrated that CZM, like bedaquiline, is synergistic in vitro with benzothiazinones such as 2-piperazino-benzothiazinone 169 (PBTZ169), and this synergy also occurs against nonreplicating bacteria. The synergy between CZM and PBTZ169 was lost in an MK-4-rich medium, indicating that MK-4 is the probable link between their activities. The efficacy of the dual combination of CZM and PBTZ169 was tested in vivo, where a great reduction in bacterial load was obtained in a murine model of chronic tuberculosis. Taken together, these data confirm the potential of CZM in association with PBTZ169 as the basis for a new regimen against drug-resistant strains of M. tuberculosis.

Mental disorders in leprosy: an underdiagnosed and untreated population

OBJECTIVE

To describe the frequency of psychiatric comorbidities in leprosy patients and check if they had been previously diagnosed and were in psychiatric care.

METHOD

The study was conducted with a sample of 120 leprosy patients being treated at two reference hospitals for leprosy in Salvador, Bahia, Brazil. Survey participants were more than 18 years of age, had a confirmed diagnosis of leprosy and was undergoing antimicrobial treatment. Patients were evaluated face-to-face with a socio-demographic questionnaire and the Mini-International Neuropsychiatric Interview (MINI-Plus) in Portuguese. The period of data collection was between October 2009 and June 2012.

RESULTS

The assessment using the MINI-Plus showed that 34 (28.3%) patients did not receive any psychiatric diagnosis and 86 (71.7%) met the criteria for at least one. Of these 86 patients, 25 (20.8%) had one diagnosis, 26 (21.7%) had two diagnoses and the rest, 35 (29.2%), had three or more psychiatric diagnoses. All patients with a moderate or high risk of suicide had one or more psychiatric comorbidities.

CONCLUSION

Leprosy patients have a high prevalence of psychiatric comorbidities. Furthermore, most of them had no previous psychiatric diagnosis and the majority was not undergoing treatment.

Minocycline-induced hyperpigmentation in multibacillary leprosy

Minocycline has been used in the treatment of leprosy since the demonstration of its efficacy in inhibiting Mycobacterium leprae growth in 1987. Hyperpigmentation, a well-documented adverse effect, classically shows 3 clinical and histological patterns: type I consists of blue-black pigmentation in areas of current or previous inflammation, type II consists of blue-gray pigmentation of normal skin, often seen on the legs, and type III consists of diffuse muddy-brown pigmentation accentuated on sun-exposed sites. Whereas type I hyperpigmentation stains positively for hemosiderin and type III hyperpigmentation stains positively for melanin, type II hyperpigmentation stains positively for both. We describe 2 patients with leprosy on minocycline therapy who developed multiple patches of blue-gray pigmentation within preexisting leprosy lesions. Biopsies from both patients demonstrated deposition of brownish-black pigment granules within the cytoplasm of foamy histiocytes that was highlighted by both Perls and Fontana-Masson stains. Given the clinical and histological findings in our patients, it is as yet unclear whether this coexistent type I clinical pattern and type II histopathologic pattern of pigmentation is unique to multibacillary leprosy. These findings provide support for the existence of additional subtypes of minocycline-induced hyperpigmentation that do not adhere to the classic 3-type model described.

Rising to the challenge: new therapies for tuberculosis

The standard treatment for tuberculosis (TB) is lengthy, complex, and significantly toxic. Drug development for TB has stagnated for decades, but in recent years renewed commitment and coordinated research has generated a modest pipeline of new drugs that hold the potential to make treatment more effective, shorter, less complex, and less toxic in the near future. With a particular focus on bedaquiline (TMC207), the first anti-TB drug of a novel class to be approved by the US Food and Drug Administration (FDA) in 40 years, this review summarizes the recent evidence behind new developments in TB treatment. Novel drug classes, repurposed drugs, and host-directed therapies are reviewed. In parallel to these exciting developments in drug discovery, we propose that it is crucial to develop more rapid and comprehensive diagnostics that will allow the timely selection of the best regimen for individual patients.

Clofazimine analogs with efficacy against experimental tuberculosis and reduced potential for accumulation

The global tuberculosis crisis urgently demands new, efficacious, orally available drugs with the potential to shorten and simplify the long and complex treatments for drug-sensitive and drug-resistant disease. Clofazimine, a riminophenazine used for many years to treat leprosy, demonstrates efficacy in animal models of tuberculosis via a novel mode of action. However, clofazimine's physicochemical and pharmacokinetic properties contribute to side effects that limit its use; in particular, an extremely long half-life and propensity for tissue accumulation together with clofazimine's dye properties leads to unwelcome skin discoloration. We recently conducted a systematic structure-activity study of more than 500 riminophenazine analogs for anti-Mycobacterium tuberculosis activity. We describe here the characteristics of 12 prioritized compounds in more detail. The new riminophenazine analogs demonstrated enhanced in vitro activity compared to clofazimine against replicating M. tuberculosis H37Rv, as well as panels of drug-sensitive and drug-resistant clinical isolates. The new compounds demonstrate at least equivalent activity compared to clofazimine against intracellular M. tuberculosis and, in addition, most of them were active against nonreplicating M. tuberculosis. Eleven of these more water-soluble riminophenazine analogs possess shorter half-lives than clofazimine when dosed orally to mice, suggesting that they may accumulate less. Most importantly, the nine compounds that progressed to efficacy testing demonstrated inhibition of bacterial growth in the lungs that is superior to the activity of an equivalent dose of clofazimine when administered orally for 20 days in a murine model of acute tuberculosis. The efficacy of these compounds, along with their decreased potential for accumulation and therefore perhaps also for tissue discoloration, warrants further study.

Protective role of vitamin E on the oxidative stress in Hansen's disease (Leprosy) patients

BACKGROUND

A constellation of reactive oxygen species (ROS) capable of damaging cellular constituents generated in excess during the chronic, inflammatory, neurodegenerative disease process of leprosy. The consequences of this leads to enhanced oxidative stress and lower antioxidant status. Enzymatic antioxidants provide first line defense against ROS. We have measured the levels of oxidative stress indices like lipid peroxidation (LPO), protein carbonyls together with enzymatic antioxidants in the blood samples of control and leprosy patients. Nutritional rehabilitation by way of exogenous supplementation of functionally efficient antioxidants like vitamin E reactivates the enzymatic antioxidant system and guards against the insult caused by ROS during the pathogenesis of the disease and antileprosy chemotherapy.

DESIGN

Untreated leprosy patients were selected on the basis of clinical examination and skin smear. All diagnosed untreated leprosy patients received multi drug therapy (MDT) consisting of rifampicin, dapsone and clofazimine as recommended by World Health Organization. A small number of untreated cases were selected for co-supplementation of vitamin E along with MDT. Oxidative stress indices, enzymatic and nonenzymatic antioxidant status were assayed in untreated, MDT treated and those supplemented vitamin E along with MDT.

STATISTICAL METHODS

We have compared the significance in the mean+/-s.d. values of the oxidative stress indices and the levels of antioxidants using one way analysis of variance (ANOVA) between control, untreated, MDT treated and those supplemented vitamin E with MDT and the results were significant at P < 0.05. Statistical analysis of the results suggests that oral administration of vitamin E lowers oxidative stress and augments antioxidant status in affected individuals.

RESULTS

Enhanced oxidative stress as evidenced by increased LPO and protein carbonyl in leprosy cases lowers the antioxidant status. Treatment with MDT has a limited impact on increased oxidative stress and decreased antioxidant status. Coadministration of vitamin E along with MDT decreases oxidative stress and activate the antioxidant status.

DISCUSSION

The excess production of ROS as seen in leprosy cases could lead to degeneration of tissues and derangement of internal organs. The possible reason for the decreased antioxidant status in leprosy cases may be increased production of ROS, deranged liver function, and the free radical producing ability of drugs used in MDT of leprosy. Intervention with antioxidant supplementation like vitamin E prevents oxidative stress mediated through ROS and activates the net antioxidant status during the chronic course of the disease and antileprosy chemotherapy.

Double-blind, randomized, controlled clinical trial of clofazimine compared with chloroquine in patients with systemic lupus erythematosus

OBJECTIVE

To evaluate the efficacy of clofazimine (CFZ) compared with chloroquine diphosphate (CDP) for the treatment of cutaneous involvement in systemic lupus erythematosus (SLE).

METHODS

A prospective, randomized, controlled, double-blind clinical trial was carried out in SLE patients with active cutaneous lesions, of whom 16 were randomized to receive CFZ at 100 mg/day and 17 received CDP at 250 mg/day for 6 months. All drugs had a similar appearance to avoid identification. Both groups received broad-spectrum sunscreens twice a day and the prednisone dose was kept stable during the study. Cutaneous lesions were evaluated by 2 blinded observers at baseline and at months 1, 2, 4, and 6.

RESULTS

Thirty-three patients were randomized to a treatment group, of whom 27 completed 6 months of treatment. The groups were homogeneous and comparable in terms of demographic and clinical characteristics. Five CFZ-treated patients and 1 CDP-treated patient (P = 0.15) dropped out due to development of severe lupus flare. At the end of the study, 12 CFZ-treated patients (75%) and 14 CDP-treated patients (82.4%) had complete or near-complete remission of skin lesions; intention-to-treat analysis showed no significant difference in the response rates between groups. Side effects, mainly skin and gastrointestinal events, were frequent in both groups, but no patients had to discontinue their treatment.

CONCLUSION

These findings suggest that CFZ is equally as effective as CDP in controlling cutaneous lesions in SLE patients. However, we cannot exclude the possibility that the CFZ itself could be the cause of systemic lupus flare.

Optimal management of recalcitrant disorders of hyperpigmentation in dark-skinned patients

Alterations in skin pigmentation may often have a dramatic expression in individuals with a dark skin complexion and can be a source of significant emotional distress in these individuals. Hyperpigmented disorders such as melanosis (melasma), post-inflammatory hyperpigmentation, drug-induced hyperpigmentation, and erythema dyschromicum perstans tend to have a prolonged course and, in many cases, are refractory to treatment, further contributing to the psychological impairment of the affected patients. Melanosis, is a common form of facial pigmentation attributable to sunlight and hormonal factors. A range of treatment modalities, such as depigmenting agents, topical retinoids, and chemical peels in conjunction with rigorous sun protection, can improve the melanosis but the condition usually recurs. Combination regimens, including frequent applications of superficial- and medium-depth chemical peels, appear to be particularly effective and well tolerated in dark-skinned patients with melanosis. Post-inflammatory hyperpigmentation is the result of excess pigment deposition following an inflammatory skin disorder. Topical tretinoin, hydroquinone, azelaic acid, kojic acid, and glycolic acid peels have been employed with variable degrees of success. Drug-induced pigmentation is a frequent cause of acquired hypermelanosis, its clinical expression depending on the triggering molecule and the underlying pathogenetic mechanism. Identifying and discontinuing the offending agent is the main approach in this condition, although, recent reports have demonstrated the efficacy of Q-switched lasers in accelerating the pigment removal. Erythema dischromicum perstans is a characteristic dermal pigmentation occurring mainly in dark-skinned individuals. Immunomodulating agents, such as clofazimine and dapsone have been shown to lighten this disorder, although, the exact mode of action is not clear.

Arbutin increases the pigmentation of cultured human melanocytes through mechanisms other than the induction of tyrosinase activity

We assessed the effects of arbutin on the pigmentation of cultured normal human melanocytes. As indicated by a cell-blotting assay, arbutin at concentrations in the range of 0.5-8 mM increased the pigmentation of the cultured melanocytes, while kojic acid at concentrations in the range of 0.5-4 mM decreased the pigmentation. The pigmentation-augmenting effect of arbutin was further confirmed by the results of a cell-pelleting assay, the traditional method of assessment. Treatment of the cells with arbutin increased the melanin content of the cells and the protein content as well. On the other hand, the tyrosinase activity in the cells was reduced by arbutin treatment. The levels of transcription of tyrosinase and tyrosinase related protein-1 genes were not affected by arbutin treatment as indicated by a semi-quantitative reverse transcription-polymerase chain reaction assay. These results demonstrate that arbutin promotes an increase in pigmentation of cultured human melanocytes that is not mediated by augmented tyrosinase activity.

Diffuse hyperpigmentation of the skin: a clinicopathologic approach to diagnosis

There are multiple causes of diffuse hyperpigmentation of the skin (DHP) and determination of the exact etiology can sometimes be difficult. A systematic classification based on both clinical and pathological findings that should aid the clinician who is confronted with this situation is presented in this article. The skin diseases that cause DHP are classified based on the pigment characteristics (melanin, non-melanin), pigment distribution (epidermal, epidermal-dermal, dermal) and density of melanocytes (normal, increased). The intent of this review is to provide a "histopathological tool" that increases diagnostic accuracy in the evaluation of a patient with DHP.

Oral lesions of iatrogenic and undefined etiology and neurologic disorders associated with HIV infection

A review of a miscellaneous group of oral mucosal disorders in the setting of infection with the human immunodeficiency virus is presented. Included is a discussion of oral lesions of iatrogenic and undefined etiology and neurologic disorders. Mechanisms of pathogenesis, including possible common pathways and relationships to underlying immunosuppression, are emphasized.