Quantitative analysis of optical coherence tomography imaging in patients with different severities of hydroxychloroquine toxicity.

PURPOSE: To determine the diagnostic validity of quantitative measures derived from optical coherence tomography (OCT) images in their ability to discriminate between cohorts of eyes unaffected by hydroxychloroquine (HCQ) and those with a range of toxicity severities, including mild toxicity. METHODS: Prospective, single-centre, case-control study conducted between August 2010 and May 2017. Participants were exposed to HCQ for at least 5 years (mean±SD =14±7.2 years) and classified into affected and unaffected cohorts based on the American Academy of Ophthalmology's 2016 recommendations. For affected eyes, severity (groups 1-4) was assigned based on the extent of ellipsoid zone loss. For all eyes, spectral domain-OCT scans were analysed quantitatively to compute inner retinal thickness (IRT), outer retinal thickness (ORT), and minimum signal intensity (MI) and compared across toxicity groups. RESULTS: Of the 85 participants (mean age 59±12 years, 93% female), 30 had retinal toxicity. Significant differences in ORT and MI were observed between each affected severity group and unaffected eyes. Significant differences in IRT were observed for groups 3-4 but not groups 1-2. ORT and MI were each able to discriminate between unaffected and group 1 eyes with the highest discrimination at the inner subfields (areas under the curve, AUC=0.96 for ORT and AUC=0.93 for MI). CONCLUSIONS: Quantitative analysis of OCT scans revealed significant differences between eyes with and without toxicity in two different measures. Each individual metric could discriminate between the unaffected and the lowest severity category, suggesting their potential utility in screening for HCQ toxicity in patients at risk.

Extreme Interocular Asymmetry in an Atypical Case of a Hydroxychloroquine-Related Retinopathy.

Background and Objectives: Long-term hydroxychloroquine (HCQ) therapy can lead to retinal toxicity. Typically, it is characterized by a bull's eye maculopathy. More recently, a "pericentral" form of HCQ retinopathy that predominantly affects patients of Asian descent has been described. To our knowledge, this is the first reported case where such an asymmetry between the right and the left eye in the toxicity profile is observed. Case presentation: The patient presented with a 12-year exposure to HCQ at a daily dose of 4.35 mg/kg. She presented an inferior pericentral-only phenotype of HCQ toxicity on the right eye and a perifoveal-only toxicity on the left eye. Modest progression of toxicity was observed on both eyes over the seven years of follow-up, despite drug discontinuation. Conclusions: To our knowledge, this is the first time that two different phenotypes of HCQ-related retinopathy are found in the same patient, challenging our understanding of the pathophysiology of HCQ retinal toxicity.

Machine Learning-Based Automated Detection of Hydroxychloroquine Toxicity and Prediction of Future Toxicity Using Higher-Order OCT Biomarkers.

OBJECTIVE: Despite guidelines for hydroxychloroquine (HCQ) toxicity screening, there are clear challenges to accurate detection and interpretation. In the current report, the feasibility of automated machine learning (ML)-based detection of HCQ retinopathy and prediction of progression to toxicity in eyes without preexisting toxicity has been described. DESIGN: Retrospective, longitudinal cohort study. SUBJECTS: Subjects on HCQ therapy. METHODS: This was an institutional review board-approved, retrospective, longitudinal image analysis of 388 subjects on HCQ. Multilayer, compartmental, retinal segmentation with ellipsoid zone (EZ) mapping was used to harvest quantitative spectral-domain (SD)-OCT biomarkers. Using a combination of clinical features (i.e., cumulative HCQ dose and the duration of therapy) and quantitative imaging biomarkers (e.g., volumetric EZ integrity and compartmental measurements), ML models were created to detect toxicity and predict progression based on ground-truth OCT-based toxicity readings by 2 masked retina specialists. Furthermore, 10-fold cross-validation was performed. MAIN OUTCOME MEASURES: The model performance was visualized using receiver operator curves and calculating the area under the curve (AUC). The corresponding sensitivity and specificity values were evaluated for the feasibility of HCQ toxicity screening and prediction. RESULTS: The prevalence of HCQ toxicity in this cohort of 388 patients was 9.8% (n = 38). Twenty-one eyes progressed to toxicity during follow-up. OCT-based features (i.e., partial EZ attenuation, EZ volume, outer nuclear layer volume, and compartmental thicknesses) and clinical features (i.e., HCQ daily dose, HCQ cumulative dose, and duration of therapy) showed significant differences between the toxic and nontoxic groups. Percentage area with partial EZ attenuation (i.e., percentage of the macula with an EZ-retinal pigment epithelium thickness of ≤ 20 µm) was the most discriminating single feature (toxic, 35.7 ± 46.5%; nontoxic, 1.8 ± 4.4%; P < 0.0001). Using a random forest model, high-performance, automated toxicity detection was achieved, with a mean AUC of 0.97, sensitivity of 95%, and specificity of 91%. Furthermore, the toxicity progression prediction model had a mean AUC of 0.89, with a sensitivity and specificity of 90% and 80%, respectively. CONCLUSIONS: This report described the feasibility of high-performance automated classification models that used a combination of clinical and quantitative SD-OCT biomarkers to detect HCQ retinal toxicity and predict progression to toxicity in cases without toxicity. Future work is needed to validate these findings in an independent dataset.

Glycolysis aggravates methotrexate toxicity by fueling RFC1-controlled intestinal absorption in rheumatic rats.

Methotrexate (MTX) is a first line anti-rheumatic drug. This study was designed to investigate the impact of rheumatoid arthritis (RA) conditions on its oral absorption, and clarify the relevance with changes of MTX absorption-related transporters in rheumatic models. MTX was orally administered to healthy, collagen-induced arthritis (CIA), and adjuvant-induced arthritis (AIA) rats. MTX plasma concentrations were determined by a validated liquid chromatography-mass spectrometry method. We found that intestinal MTX absorption was significantly increased in CIA/AIA rats versus healthy controls. This finding was supported by small intestine-based MTX uptake assay in vitro. Meanwhile, intestinal expression of both reduced folate carrier 1 (RCF1) and proton-coupled folate transporter (PCFT) remained unchanged. The everted intestinal sac assay confirms RFC1 is the key transporter accounting for intestinal MTX absorption, as its antagonist salicylazosulfapyridine showed potent capacity in reducing MTX uptake. No correlation between RA-related cytokines and RCF1 expression was observed in clinical samples. We further revealed that when cultured with AIA rat or RA patient serum, lactate and adenosine triphosphate (ATP) production as well as MTX uptake in MDCKII cells were significantly increased, and this increase was completely abrogated by ATP production-related metabolic inhibitors. Thanks to its inhibitory effects on MTX bioavailability, the glycolysis inhibitor shikonin diminished MTX-induced injuries of kidney and liver in AIA rats. These data demonstrate that glycolysis-driven high energy metabolism increases MTX absorption in rheumatic subjects, leading to the exacerbated toxicity. These findings will have important implications in optimizing MTX regimens for RA treatment with better efficacy and lower toxicity.

A novel 5-ring multifocal electroretinography stimulus for detecting hydroxychloroquine retinal toxicity.

PURPOSE: Multifocal electroretinogram (mfERG) shows great utility as a screening tool to detect early hydroxychloroquine (HCQ) retinopathy, but its widespread use is limited by the lack of accessibility and long test duration. In this study, we evaluated a novel concentric 5-ring mfERG stimulus to provide a simplified and rapid protocol for screening HCQ toxicity. METHODS: Patients referred for HCQ retinopathy screening were consented to this observational cross-sectional study. Patients with amblyopia, high refractive error (more than 8 diopters), other retinal diseases precluding appropriate evaluation or history of retinal surgery were excluded. The data were collected from patients undergoing HCQ screening at a single center from July 2019 to March 2020. Patients were tested with the new concentric 5-ring mfERG stimulus, standard 61-hexagon mfERG stimulus, spectral domain optical coherence tomography and automated 10-2 visual fields. For the main outcome, the 5-ring mfERG was compared to 61-hexagon stimulus to determine the time-to-test completion and assess the association between ring (R1-R5) amplitude and ring ratio compared against cumulative dose, dose by real body weight and duration of therapy using Pearson correlation. RESULTS: In total, 52 patients (104 eyes; 5 males and 47 females) were recruited with a mean age of 59 years (range 23-85 years). The 5-ring protocol was markedly quicker to perform (1.3 ± 0.2 min; mean (SD)) compared to the 61-hexagon protocol (5.2 ± 0.6 min), p < 0.0001; n = 10 patients. The new R2/R5 ring ratio showed a moderate correlation with daily dose (r = - 0.640), cumulative dose (r = - 0.581) and duration of therapy (r = - 0.417). Similar correlations were observed with the new R2/R4 ring ratio which were not significantly different from the new R2/R5 correlation coefficients. The new R2/R5 ring ratio demonstrated a stronger correlation with daily (p = 0.002) and cumulative dose (p = 0.0001) compared to the 61-hexagon stimulus. CONCLUSIONS: In this exploratory study, our novel 5-ring mfERG protocol significantly shortened data acquisition time while providing comparable results to the standard 61-hexagon stimulus for detecting HCQ-induced electrophysiological changes that are correlated with HCQ dosages and treatment duration. Our protocol has the potential to be more clinically practical by simplifying routine screening.

Impact of Structural Changes on Multifocal Electroretinography in Patients With Use of Hydroxychloroquine.

Purpose: To investigate the relationship between retinal structure and macular function in eyes screened for hydroxychloroquine (HCQ) toxicity. Methods: Participants referred for hydroxychloroquine retinopathy screening with spectral domain optical coherence tomography (SD-OCT) and multifocal electroretinogram (mfERG) testing were included in the analysis. Amplitude and implicit time of mfERG N1 and P1 responses were included in the analysis. Ring ratios were computed for amplitude values as the ratio of rings 1-3:5 (R1-3:R5). A control group of healthy participants was included for comparison of SD-OCT metrics. Results: Sixty-three eyes screened for HCQ retinopathy and 30 control eyes were analyzed. The outer nuclear layer (ONL) was significantly thinner in HCQ patients in the foveal (P = 0.008), parafoveal (P < 0.0001), and perifoveal (P < 0.0001) regions. The HCQ cohort was further divided into two subgroups according to the presence of structural clinically detectable retinopathy (i.e., structural damage as detected by multimodal imaging). HCQ eyes without retinopathy had a thinner ONL thickness in the foveal (P = 0.032), parafoveal (P < 0.0001), and perifoveal (P < 0.0001) regions and a thinner inner nuclear layer (INL) in the parafoveal region (P = 0.045 versus controls). Structural changes in HCQ patients without retinopathy were significantly associated with macular function as R2:R5 ring ratio of mfERG P1 amplitude was associated with INL (P = 0.002) and ONL (P = 0.044) thicknesses, and R3:R5 ring ratio of P1 amplitude was associated with ONL thickness (P = 0.004). Conclusions: Our results suggest that structural alterations secondary to HCQ toxicity may occur in the absence of clinically detectable retinopathy, and this may reflect in an impaired macular function.

Hepatotoxic potentials of methotrexate: Understanding the possible toxicological molecular mechanisms.

Methotrexate (MTX) is one of the most effective and widely used drugs in the management of autoimmune and dermatological diseases. Rheumatoid arthritis and psoriasis patients who are under long term MTX-therapy are at high risk of developing a liver injury. Accumulation of intracellular MTX-polyglutamate (MTX-PG), a metabolite of MTX triggers oxidative stress, inflammation, steatosis, fibrosis, and apoptosis in hepatocytes. MTX-PG causes oxidative stress in the liver by inducing lipid peroxidation thereby releasing reactive oxygen species and suppressing antioxidant response elements. MTX-PG induces several pro-inflammatory signaling pathways and cytokines such as tumor necrosis factor-α, nuclear factor kappa B and interleukin 6 (IL-6), IL- ß1, IL-12. MTX-PG depletes hepatic folate level and decreases RNA and DNA synthesis leading to hepatocyte death. MTX-PG inhibits 5-aminoimidazole-4-carboxamide ribonucleotide transformylase enzyme and thereby causes accumulation of intracellular adenosine, which causes activation of hepatic stellate cells, extracellular matrix accumulation and hepatic fibrosis. MTX-PG induces hepatocytes apoptosis by activation of caspase 3 via the intrinsic pathway. Clinically, aggravation of underlying fatty liver to non-alcoholic steatohepatitis with fibrosis seems to be an important mechanism of liver injury in MTX-treated RA patients. Therefore, there is a need for monitoring liver injury in RA, psoriatic and cancer patients with NAFLD and fibrosis risk factors during MTX treatment. This review summarizes the possible molecular mechanism of MTX-induced hepatotoxicity. It may pave the way for early detection of liver injury and develop novel strategies for treating MTX mediated hepatotoxicity.

Liver X receptors conserve the therapeutic target potential for the treatment of rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic multi-system autoimmune disease with extremely complex pathogenesis. Significantly altered lipid paradox related to the inflammatory burden is reported in RA patients, inducing 50% higher cardiovascular risks. Recent studies have also demonstrated that lipid metabolism can regulate many functions of immune cells in which metabolic pathways have altered. The nuclear liver X receptors (LXRs), including LXRα and LXRß, play a central role in regulating lipid homeostasis and inflammatory responses. Undoubtedly, LXRs have been considered as an attractive therapeutic target for the treatment of RA. However, there are some contradictory effects of LXRs agonists observed in previous animal studies where both pro-inflammatory role and anti-inflammatory role were revealed for LXRs activation in RA. Therefore, in addition to updating the knowledge of LXRs as the prominent regulators of lipid homeostasis, the purpose of this review is to summarize the effects of LXRs agonists in RA-associated immune cells, to explore the underlying reasons for the contradictory therapeutic effects of LXRs agonists observed in RA animal models, and to discuss future strategy for the treatment of RA with LXRs modulators.

Hyaluronate-functionalized hydroxyapatite nanoparticles laden with methotrexate and teriflunomide for the treatment of rheumatoid arthritis.

Rheumatoid arthritis (RA), an autoimmune inflammatory disorder is currently incurable. Methotrexate and Teriflunomide are routinely prescribed drugs but their uses are limited due to severe hepatotoxicity. Hyaluronic acid (HYA) is a targeting ligand for CD44 receptors overexpressed on inflamed macrophages. The present investigation aimed at design and fabrication of HYA coated hydroxyapatite nanoparticles (HA-NPs) loaded with Methotrexate (MTX) and Teriflunomide (TEF) (HAMT-NPs) to form HYA-HAMT-NPs for the treatment of RA. HYA-HAMT-NPs showed the nanoscale size of 274.9 ± 64 nm along with a zeta potential value of -26.80 ± 6.08 mV. FTIR spectra of HYA and HYA-HAMT-NPs proved the coating of HYA on HYA-HAMT-NPs. HYA-HAMT-NPs showed less cell viability compared to drugs on RAW 264.7 macrophage cells. A biodistribution study by gamma scintigraphy imaging further strengthened the results by revealing significantly higher (p<0.05) percentage radioactivity (76.76%) of HYA-HAMT-NPs in the synovial region. The results obtained by pharmacodynamic studies ensured the better efficacy of HYA-HAMT-NPs in preventing disease progression and promoting articular regeneration. Under hepatotoxicity evaluation, liver histopathology and liver enzyme assay revealed ~29% hepatotoxicity was reduced by HYA-HAMT-NPs when compared to conventional FOLITRAX-10 and AUBAGIO oral treatments. Overall, the results suggest that HYA-HAMT-NP is a promising delivery system to avoid drug-induced hepatotoxicity in RA.

"Protenuria in SLE: Is it always lupus?"

Proteinuria is one of the most typical manifestations of kidney involvement in Systemic Lupus Erythematosus (SLE). We report the case of a 23-year-old woman with a 6-year-long history of SLE presenting with proteinuria after a three-year remission on hydroxychloroquine. Kidney histological examination showed alterations inconsistent with lupus nephritis and suggestive of hydroxychloroquine toxicity or Fabry disease. The latter was confirmed by genetic assay.

The influence of obesity on hydroxychloroquine blood levels in lupus nephritis patients.

INTRODUCTION: In 2016 the American Academy of Ophthalmology(2016-AAO) recommended a maximum daily HCQ use of 5.0 mg/kg real body weight(RBW) taking into consideration minimizing eye toxicity. Retinopathy in systemic lupus erythematosus(SLE) patients was recently associated with obesity and this condition is progressively more common in these patients. However, the impact of obesity in HCQ blood levels remains controversial. OBJECTIVE: To determine if the 2016-AAO recommendation based on RBW with and without maximum daily dose restriction results in adequate and safe blood levels in obese lupus nephritis(LN) patients. METHODS: A cross-sectional study was performed with 108 LN patients under the prescribed 2016-AAO dose for at least 3 months. LN patients were assessed for demographic characteristics, body mass index(BMI), disease parameters, HCQ dose, concomitant treatment and HCQ blood levels measured by liquid chromatography-tandem mass spectrometry. Obesity was defined as BMI ≥30kg/m2. RESULTS: Obesity was identified in 35/108(32%) LN patients. The calculation of HCQ daily dosage revealed that obese patients were under a lower prescribed daily dose according to the real body weight (RBW) [4.4(2.9-5.4) vs. 4.9(4-5.5)mg/Kg/day, p < 0.001] due to the maximum limit used. Regardless of that the median of HCQ blood levels was significantly higher in obese compared to non-obese patients (1562 ± 548.6 vs. 1208 ± 448.9 ng/mL, p = 0.002). Further analysis of patients under the 20016-AAO recommendation by RBW without the restriction of maximum daily dose confirmed that in spite of comparable daily dose in 14 obese patients and 61 non-obese patients [4.8 (4.5-5.4) vs. 5.0(4.5-5.5) mg/kg, p = 0.312], the median of HCQ blood levels was significantly higher in obese patients than in non-obese (1734 ± 457.3 vs. 1189 ± 449.4 ng/mL, p < 0.001). CONCLUSION: Obese patients under the 2016-AAO prescribed dose of HCQ based on RBW with and without maximum daily dose restriction have a very high HCQ blood levels compared to non-obese patients, with a potential increased risk of ocular toxicity. The use of 2016-AAO dose of HCQ according to the ideal body weight for this group of patients should be considered.Clinicaltrials.gov #NCT0312243.

SEQUENTIAL RETINAL THICKNESS ANALYSIS SHOWS HYDROXYCHLOROQUINE DAMAGE BEFORE OTHER SCREENING TECHNIQUES.

PURPOSE: We sought to determine the earliest diagnostic signs of hydroxychloroquine retinopathy up to the point of clinical recognition. METHODS: Retrospective series of 6 patients (5 parafoveal disease; 1 pericentral disease) with at least 3 examinations over 3.5 years or more preceding diagnosis of HCQ retinopathy. Spectral domain optical coherence tomography (sdOCT) cross-sections, fundus autofluorescence (FAF) and visual fields were generated clinically. Stored sdOCT data were re-examined later to generate topographic ellipsoid zone (EZ) maps, minimum intensity (MI) analysis and sequential plots of regional retinal thickness. Retrospective series of six patients (5 parafoveal disease; one pericentral disease) with at least three examinations over 3.5 years or more preceding diagnosis of hydroxychloroquine retinopathy. RESULTS: Spectral domain optical coherence tomography cross-sections and fields showed similar sensitivity; fundus autofluorescence was not helpful. In parafoveal cases, EZ topography and minimum intensity analysis were no more reliable. Sequential thickness plots from four parafoveal cases showed dramatic retinal thinning across the posterior pole beginning 4 years to 5 years before clinical diagnosis, with parafoveal regions thinning even faster. The pericentral case showed thinning only outside the central macula. Peripheral EZ loss was more dramatic with EZ topography than sdOCT cross-sections. CONCLUSION: Sequential retinal thickness plots reveal definitive thinning years before current diagnostic procedures. We hope that OCT manufacturers will develop software to display such measurements. Ellipsoid zone topography was not more sensitive than sdOCT cross-sections, but important for recognizing pericentral disease.

ASYMMETRIC HYDROXYCHLOROQUINE MACULAR TOXICITY WITH APHAKIC FELLOW EYE.

BACKGROUND/PURPOSE: Retinal toxicity associated with antimalarial drug use in inflammatory conditions is well described and may be more common than previously recognized. Antimalarial drugs bind to melanin in ocular tissues, particularly the retinal pigment epithelium, but the mechanism of toxicity and its relation to light is unclear. METHODS: Case report. RESULTS: A 62-year-old white woman with erosive rheumatoid arthritis developed hydroxychloroquine toxicity in her phakic eye, with her aphakic fellow eye only mildly affected. CONCLUSION: We report the clinical evaluation of this rare case of asymmetrical hydroxychloroquine retinopathy and present a hypothesis regarding the mechanism of drug toxicity.

Toxicity studies and anti-arthritic effect of mandelic acid (2-hydroxy -2-phenyl acetic acid) using in vitro and in vivo techniques.

The major concern to search for new anti-arthritic drugs is primarily to prevent systemic complications and to maintain quality of life. As these drugs are prescribed for long duration so the objective is to ensure their safety in terms of toxicity. By keeping in view this concept, the present study was investigated to determine new anti-arthritic potential using in-vitro and in-vivo methods. The in-vitro tests comprised of protein denaturation (BSA and egg albumin) and Human Red Blood cell (HRBC) membrane stabilization assays at 50-6400µg/mL, for in-vivo testing, formaldehyde-induced arthritic rats were treated with 40, 80 and 160mg/kg mandelic acid. Mandelic acid (MA) inhibited the protein denaturation and stabilized the membrane of HRBC in a concentration dependent manner. Likewise, mandelic acid exhibited dose dependent reduction in paw volume induced by formaldehyde. For acute and sub-acute treatment, MA did not show any sign of toxicity and mortality in each rat and LD50 might be greater than 2000mg/kg. In addition, histopathological assessment presented slight increased interstitial spaces in the kidney, disorganization of glomerulus, dilated sinusoids at highest dose 800mg/kg which were not observed in sub-chronic therapy. Hence, these results conclude that mandelic acid has the potential to treat rheumatoid arthritis with observed no significant signs of toxicity and should be tested further to determine anti-arthritic mechanism of drug action at cellular level.

Improving eye screening practice among pediatric rheumatology patients receiving hydroxychloroquine.

OBJECTIVE: Hydroxychloroquine (HCQ) is commonly used in the treatment of various autoimmune diseases related to its many benefits and favorable safety profile. Although HCQ retinopathy was considered to be uncommon, a prevalence of 7.5% was described in a recent study making early detection critical. The most updated screening guidelines by the American Academy of Ophthalmology were published in 2016; however, it lacked pediatric-specific recommendations and the overall compliance with screening guidelines was poor in previous studies. We developed a quality improvement (QI) initiative aiming to create institutional screening recommendations. Additionally, to increase eye screening in pediatric rheumatology clinic for patients receiving HCQ from 65% to 85% in 12 months and to sustain that rate for at least 6 months. METHODS: We formed a multidisciplinary team of pediatric rheumatologists and ophthalmologists, clinical pharmacist, clinic nurses, QI specialist, quality data technician and administrative staff. We included patients receiving HCQ and who were evaluated at Nationwide Children's Hospital rheumatology clinic. A key driver diagram was formulated to identify barriers to compliance and determine possible interventions. Main interventions included summarizing screening guidelines in a step by step algorithm, increasing awareness of these guidelines among patients and providers, improving collaboration and communication with ophthalmologists, and initiating pre-visit planning. RESULTS: Baseline performance data included 164 patients. Fifty-four (33%) of those patients were at high risk for HCQ retinopathy. Of them, 50% were on HCQ dose of >5 mg/kg/day and 31.5% had been taking HCQ for ≥5 years. Two center line shifts were noticed over the course of the project. The target of 85% compliance was reached in February 2019 and was sustained until December 2019. CONCLUSIONS: Our study highlights the importance of interdisciplinary communication to increase awareness of screening guidelines among medical providers and patients. Pre-visit planning played a major role in identifying patients and opportunities for optimizing eye screening in patients at risk for HCQ retinopathy. Collaboration between rheumatologists and ophthalmologists is crucial in managing patients on HCQ. The implementation of same-day eye screening allowed this collaboration to be more efficient. Future efforts are being directed at monitoring and improving utilization of the effective interventions.

Development and characterisation of novel poly (vinyl alcohol)/poly (vinyl pyrrolidone)-based hydrogel-forming microneedle arrays for enhanced and sustained transdermal delivery of methotrexate.

Methotrexate (MTX) is one of the mainstays of treatment for rheumatoid arthritis (RA) and juvenile idiopathic arthritis (JIA) and it is mainly administered either orally or by subcutaneous (SC) injection, which are not so satisfactory. While orally administered MTX is associated with variable bioavailability and causes gastrointestinal side effects, including nausea and vomiting, SC injection is painful and produces high peak blood levels of MTX. Transdermal delivery presents an attractive alternative administration route. However, MTX passive permeation through the skin is hindered by the skin barrier and MTX physicochemical properties. To address these issues, hydrogel-forming microneedle arrays (HFMN) and a patch-like reservoir loaded with MTX (MTX-RV) were developed and combined to form a minimally invasive patch to deliver MTX transdermally in a sustained manner. HFMN were prepared from an aqueous blend of poly (vinyl alcohol) (PVA) and poly (vinyl pyrrolidone) (PVP) which was crosslinked chemically with citric acid (CA) at 130˚C. MTX-RV was prepared from hydroxypropyl methylcellulose (HPMC) and glycerol. Both the HFMN and MTX-RV were fully characterised and then combined to form an integrated patch, which was evaluated ex vivo and in preclinical studies. The HFMN demonstrated a satisfactory mechanical strength and insertion capability into excised neonatal porcine skin, as well as moderate swelling properties. The MTX-RV incorporated a high dose of MTX (150.3 ± 5.3 µg/mg) without precipitation. The integrated patch delivered MTX at a steady-state flux of 506.8 ± 136.9 µg.cm2/h in an ex vivo setup. Furthermore, in preclinical studies performed in Sprague Dawley rats, MTX appeared in blood after 1 h from patch application at a concentration of 7.6 ± 2.0 nM. MTX blood level increased gradually to reach its peak, Cmax = 35.1 ± 5.1 nM, at 24 h. Importantly, the HFMN were removed intact from the skin with only mild erythema, despite the cytotoxic nature of MTX. Accordingly, the integrated patch produced in this work represents a promising minimally invasive transdermal drug delivery system that can overcome the skin barrier and deliver MTX in a sustained manner. This may help in minimising or even avoiding the nausea and vomiting, associated with the conventional administration routes.

What every nephrologist needs to know about hydroxychloroquine toxicity
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Hydroxychloroquine (HCQ) has become the rheumatologists's "Swiss army knife" when it comes to managing the rheumatologic manifestations of SLE and other auto-immune disorders. By contrast, nephrologists are much less comfortable in managing the multifaceted effect of HCQ. As a result, nephrologists are inclined to abdicate their responsibility for HCQ management, if this therapy was initiated by a rheumatologist. This report describes such a situation, which had devastating consequences for the patient. On this basis we suggest that this report is a story worth telling, and should encourage the nephrologist to be more involved in their patients' HCQ management.