Updated recommendations on the use of hydroxychloroquine in dermatologic practice

Utility of hydroxychloroquine laboratory monitoring in dermatologic and rheumatologic patients

Hydroxychloroquine (HCQ) is an immunomodulator used in dermatology and rheumatology. Side effects may be observed on routine monitoring studies before they become clinically apparent. The goal of this retrospective chart review was to assess laboratory abnormalities in dermatologic and rheumatologic patients taking HCQ. Medical records of patients prescribed HCQ were retrospectively reviewed. Demographics, reported side effects, and parameters on baseline and follow-up complete blood count (CBC) and comprehensive metabolic panel (CMP) were recorded and graded. Laboratory abnormalities were considered severe if they were grade 3 or greater according to Common Terminology Criteria for Adverse Events v3.0 and persistent if they continued beyond subsequent laboratory testing. Of 646 eligible charts, 289 had monitoring studies for review. There were 35 severe (grade 3 or 4, 35/289; 12%) adverse events that developed, as noted on CBC or CMP. Of these 35 severe adverse events, 25 self-corrected on subsequent testing, and 10 (10/289, 3%) across 9 patients were persistent, including glomerular filtration rate, alanine transferase, alkaline phosphatase, glucose, hemoglobin and lymphopenia abnormalities. Of these 10 abnormalities, 7/10 (70%) were unlikely due to hydroxychloroquine use according to the calculated Naranjo score for each patient. Severe laboratory abnormalities while taking hydroxychloroquine are rare, even in a population with a high rate of comorbidities. Among the abnormalities observed, the majority of them (70%) were likely due to disease progression or a medication other than hydroxychloroquine. CBC and CMP monitoring for the reason of observing abnormalities while on HCQ should be at the discretion of the prescribing physician.

Dermatologists' and Rheumatologists' Adherence to the Latest Recommendations for Screening of Hydroxychloroquine Retinopathy in Saudi Arabia: A Cross-Sectional Study

INTRODUCTION

 Hydroxychloroquine (HCQ) is used to manage the symptoms of inflammatory rheumatic and dermatologic disorders. However, HCQ retinopathy is a serious side effect because even after the drug is discontinued, irreversible vision loss may occur and may continue to progress. According to the American Academy of Ophthalmology (AAO), the recent recommendation for HCQ dosing is ≤5 mg/kg of real body weight, with baseline ophthalmologic screening during the first year of HCQ treatment and yearly screening after five years of continuous use of HCQ medication, unless the patient is at high risk or symptoms have developed. Nonetheless, this study aims to assess dermatologists' and rheumatologists' adherence in Saudi Arabia to the 2016 AAO HCQ retinal toxicity guidelines.

METHODS

 A questionnaire-based cross-sectional study was conducted on dermatologists and rheumatologists in Saudi Arabia. It was conducted between August and September 2022 and questionnaires were sent to dermatologists and rheumatologists via their professional emails or accounts.

RESULTS

The collected sample consisted of 635 participants; males and females represented 54% and 46%, respectively; 47.6% were consultants; 50.1% were rheumatologists; and 49.9% were dermatologists. Approximately 28.2% of the participants reported treating one to three patients with HCQ in the previous year. Only 45.4% of the respondents stated that the ideal recommended HCQ dose for reducing the risk of retinopathy is "≤ 5 mg/kg of the real body weight." More than 50% of the respondents stated that systemic lupus erythematosus was the most common disease for which they used HCQ. Additionally, 36.5% of the physicians screened patients during the first year of HCQ treatment. We found significant associations between practice levels and specialty practice-related questions with a p-value of less than 0.05, except for the specialty practice-related question, "What is the most common disease for which you use HCQ?" with a p-value of 0.074. Also, we found significant associations between all demographic variables and screening-related variables with a p-value of less than 0.05, with two exceptions: no significant associations were found between specialty area and the screening-related question, "Do you recommend screening tests for all patients starting treatment with HCQ?" at p = 0.270, and gender and the screening-related question, "When would you recommend screening tests for a patient without risk?" at p = 0.142.

CONCLUSIONS

 Dermatologists and rheumatologists in Saudi Arabia have shown poor adherence to the most recent AAO recommendations. Educating physicians and patients about the AAO guidelines is needed for HCQ to be used in a way that is both effective and safe.

Use of Hydroxychloroquine in Hair Disorders

Hydroxychloroquine (HCQ) is an antimalarial that is utilized to treat a range of dermatologic and autoimmune disorders. With its ability to alter immunologic mechanisms, it has been used to slow or halt the progression of hair loss in conditions secondary to autoimmune dysfunction. Lichen planopilaris (LPP), frontal fibrosing alopecia (FFA), and alopecia areata (AA) are hair disorders with underlying autoimmune components and no standardized treatment guidelines. We summarized the available literature on the use of HCQ to treat LPP, FFA, and AA. For all three conditions, HCQ showed variable efficacy from halted hair loss to no improvement. While patients did show success with HCQ treatment, there were no clear treatment patterns. Regimens ranged from HCQ monotherapy to combination treatments with other agents like steroids. Overall, HCQ should certainly be considered by clinicians as a treatment option for patient suffering from these hair disorders. While there is no standardized treatment, incorporation of HCQ should take into consideration individual patient characteristics, clinical judgment, and risks of side effects.

Hydroxychloroquine-induced Retinal Toxicity

Long-term use of hydroxychloroquine can cause retinopathy, which may result in severe and progressive visual loss. In the past decade, hydroxychloroquine use has markedly increased and modern retinal imaging techniques have enabled the detection of early, pre-symptomatic disease. As a consequence, the prevalence of retinal toxicity in long-term hydroxychloroquine users is known to be higher than was previously estimated. The pathophysiology of the retinopathy is incompletely characterised, although significant advances have been made in understanding the disease from clinical imaging studies. Hydroxychloroquine retinopathy elicits sufficient public health concern to justify the implementation of retinopathy screening programs for patients at risk. Here, we describe the historical background of hydroxychloroquine retinopathy and summarize its current understanding. We review the utility and limitations of each of the mainstream diagnostic tests used to detect hydroxychloroquine retinopathy. The key considerations towards a consensus on the definition of hydroxychloroquine retinopathy are outlined in the context of what is known of the natural history of the disease. We compare the current screening recommendations for hydroxychloroquine retinopathy, identifying where additional evidence is required, and the management of proven cases of toxicity. Finally, we highlight the areas for further investigation, which may further reduce the risk of visual loss in hydroxychloroquine users.

Quantitative autofluorescence findings in patients undergoing hydroxychloroquine treatment

Background

Methods

Results

Conclusions

[Translated article] Hydroxychloroquine: An Essential Drug in Dermatology and Its Controversial Use in COVID-19

Hydroxychloroquine is an antimalarial drug with immunomodulatory, anti-inflammatory, antibacterial, and antiviral properties. It has a good safety profile, can be used in children and in pregnant and breastfeeding women, and does not suppress the immune system. Regular screening for retinopathy, one of the drug’s most feared adverse effects, is necessary. Hydroxychloroquine is a widely used, essential drug in dermatology. Clinical response rates are good in lupus erythematous, where it is a first-line therapy, as well in numerous autoimmune/inflammatory diseases, including lichen planus, polymorphic light eruption, porphyria cutanea tarda, granuloma annulare, and sarcoidosis. In 2020, it was widely prescribed both to prevent and to treat COVID-19 caused by SARS-CoV-2. Its increased use led to serious supply shortages and in some cases stocks were entirely depleted. Recent meta-analyses have concluded that hydroxychloroquine is ineffective against COVID-19 and have advised against its use.

[Hydroxychloroquine: An Essential Drug in Dermatology and Its Controversial Use in COVID-19]

Hydroxychloroquine is an antimalarial drug with immunomodulatory, anti-inflammatory, antibacterial, and antiviral properties. It has a good safety profile, can be used in children and in pregnant and breastfeeding women, and does not suppress the immune system. Regular screening for retinopathy, one of the drug's most feared adverse effects, is necessary. Hydroxychloroquine is a widely used, essential drug in dermatology. Clinical response rates are good in lupus erythematous, where it is a first-line therapy, as well in numerous autoimmune/inflammatory diseases, including lichen planus, polymorphic light eruption, porphyria cutanea tarda, granuloma annulare, and sarcoidosis. In 2020, it was widely prescribed both to prevent and to treat COVID-19 caused by SARS-CoV-2. Its increased use led to serious supply shortages and in some cases stocks were entirely depleted. Recent meta-analyses have concluded that hydroxychloroquine is ineffective against COVID-19 and have advised against its use.

Hydroxychloroquine: An Essential Drug in Dermatology and Its Controversial Use in COVID-19

Hydroxychloroquine is an antimalarial drug with immunomodulatory, anti-inflammatory, antibacterial, and antiviral properties. It has a good safety profile, can be used in children and in pregnant and breastfeeding women, and does not suppress the immune system. Regular screening for retinopathy, one of the drug's most feared adverse effects, is necessary. Hydroxychloroquine is a widely used, essential drug in dermatology. Clinical response rates are good in lupus erythematous, where it is a first-line therapy, as well in numerous autoimmune/inflammatory diseases, including lichen planus, polymorphic light eruption, porphyria cutanea tarda, granuloma annulare, and sarcoidosis. In 2020, it was widely prescribed both to prevent and to treat COVID-19 caused by SARS-CoV-2. Its increased use led to serious supply shortages and in some cases stocks were entirely depleted. Recent meta-analyses have concluded that hydroxychloroquine is ineffective against COVID-19 and have advised against its use.

Drug repurposing of dermatologic medications to treat coronavirus disease 2019: Science or fiction?

No pharmaceutical products have been demonstrated to be safe and effective to specifically treat coronavirus disease 2019 (COVID-19); therefore, the therapy administered to infected patients remains symptomatic and empiric. Alongside the development of new, often high-cost drugs, a different tactic is being applied in parallel, investigating long-established, inexpensive medications originally designed for a variety of diseases to study their potential in treating COVID-19. The skin is the largest organ of the human body. With more than 3,000 skin conditions identified, the specialty of dermatology offers a rich armamentarium of systemic therapeutic agents aimed to treat the various chronic immunologically mediated, metabolic, infectious, occupational, inherited, or paraneoplastic dermatoses. Dermatologists have extensive experience with many drugs that have demonstrated promising in vitro antiviral action (directly targeting the viral replication). Many of these drugs have been used as nonspecific immunosuppressive strategies, such as glucocorticoids, synthetic antimalarials, colchicine, or other immunomodulators, and a number of targeted therapeutics have been directed at controlling hyperinflammatory processes similar to the "cytokine storm" associated with COVID-19 infection. We discuss several dermatologic drugs that have already been used or may have a promising role in the treatment of COVID-19.

The efficacy of antimalarial drugs in the therapy of selected forms of cicatricial alopecia

INTRODUCTION

Frontal fibrosing alopecia (FFA) is primary lymphocytic cicatricial alopecia with a clinically characteristic progressive recession of the frontotemporal hairline, perifollicular erythema, as well as symptoms of itching and burning. It occurs mainly in postmenopausal women. FFA is considered as a subtype of lichen planopilaris (LPP). The treatment of those diseases is presently empirical.

AIM

To define the efficacy of treating FFA and LPP with hydroxychloroquine.

MATERIAL AND METHODS

We performed a retrospective analysis of 95 women, including 35 with FFA and 60 with LPP. We collected the relevant demographic and clinical data. The response to treatment with hydroxychloroquine was assessed using LPPAI. Also, adverse events were monitored.

RESULTS

Treatment with hydroxychloroquine has a statistically significant effect on decreasing the disease activity after 6 and 12 months of therapy. The results of statistical tests do not confirm the existence of a relationship between age range and treatment efficacy. However, there is a correlation between the duration and efficacy of treatment (p < 0.05).

CONCLUSIONS

Administration of hydroxychloroquine can be considered as one of the treatment methods for FFA and LPP in everyday clinical practice. The presented study is the first attempt at using hydroxychloroquine to treat such large patient groups for FFA and LPP. Hydroxychloroquine efficaciously alleviates the symptoms in LPP patients and gives maximum benefits in long-term therapy (12 months). The preliminary results obtained in the presented retrospective analysis should be confirmed in a randomized prospective clinical trial, which remains a future challenge for researchers.

[Drug-induced toxidermia in a patient receiving hydroxychloroquine as systemic therapy for primary Gougerot-Sjögren syndrome: a case report]

Nous rapportons un cas d´exanthème maculo-papuleux apparu après une semaine de prise de l´hydroxychloroquine 400mg prescrite pour une atteinte articulaire d´un syndrome de Gougerot-Sjögren primaire chez une patiente de 41 ans. Cette dernière était suivie pour une lésion glomérulaire minime idiopathique depuis plus d´un an, traitée efficacement avec la corticothérapie. Les exanthèmes maculo-papuleux ont régressé après avoir reçu l´hydrocortisone, la desloratadine et l´arrêt immédiat de l´hydroxychloroquine. Notre cas reflète l´importance d´insister sur la prescription à faible dose de l´hydroxychloroquine chez les sujets avec des pathologies préexistantes rénales et aussi l´intérêt de sensibiliser et d´éduquer les patients des effets secondaires de l´hydroxychloroquine.

Management of Pediatric Chronic Spontaneous Urticaria: A Review of Current Evidence and Guidelines

Chronic urticaria (CU) is associated with debilitating symptoms such as pruritic wheals and/or angioedema, which can significantly affect patients’ sleep, productivity and quality of life. Chronic spontaneous urticaria (CSU) is defined in cases in which no triggering factor is identified. Various guidelines directing the optimal management of CU in the adult population were published and updated over the recent years with the most accepted and widely used being the EAACI/GA²LEN/EDF/WAO 2017 guidelines. Meanwhile, guidelines specific to the pediatric population are scarce, mainly due to the fact that high quality evidence is lacking for many treatment options in this age group. The objective of this article is to review and synthesize the existing literature regarding the management of pediatric CSU. Our review highlights evidence supporting the EAACI/GA²LEN/EDF/WAO 2017 treatment guidelines with non-sedating second-generation antihistamines (sgAHs) as the mainstay of treatment for pediatric CSU, considering their demonstrated efficacy and reassuring safety profile. Additionally, the use of omalizumab in adolescents is well supported by the current literature. There is limited data available regarding the updosing of sgAHs, omalizumab in children with CSU under 12 years of age and the treatment with cyclosporine and leukotriene receptor antagonists (LTRAs) in pediatric patients of all ages. However, the results from currently available case series and case reports are promising for omalizumab and cyclosporine use in children with CSU, although large and well-designed randomized control trials (RCTs) assessing these treatment options are needed in order to formulate strong recommendations for their use. First-generation antihistamines (fgAHs) remain commonly used in pediatric CSU treatment despite a lack of studies assessing their efficacy and safety in the pediatric population and their widely known inferior safety profile compared to sgAHs.

Multicenter Initial Guidance on Use of Antivirals for Children With Coronavirus Disease 2019/Severe Acute Respiratory Syndrome Coronavirus 2

BACKGROUND

Although coronavirus disease 2019 (COVID-19) is mild in nearly all children, a small proportion of pediatric patients develop severe or critical illness. Guidance is therefore needed regarding use of agents with potential activity against severe acute respiratory syndrome coronavirus 2 in pediatrics.

METHODS

A panel of pediatric infectious diseases physicians and pharmacists from 18 geographically diverse North American institutions was convened. Through a series of teleconferences and web-based surveys, a set of guidance statements was developed and refined based on review of best available evidence and expert opinion.

RESULTS

Given the typically mild course of pediatric COVID-19, supportive care alone is suggested for the overwhelming majority of cases. The panel suggests a decision-making framework for antiviral therapy that weighs risks and benefits based on disease severity as indicated by respiratory support needs, with consideration on a case-by-case basis of potential pediatric risk factors for disease progression. If an antiviral is used, the panel suggests remdesivir as the preferred agent. Hydroxychloroquine could be considered for patients who are not candidates for remdesivir or when remdesivir is not available. Antivirals should preferably be used as part of a clinical trial if available.

CONCLUSIONS

Antiviral therapy for COVID-19 is not necessary for the great majority of pediatric patients. For those rare cases of severe or critical disease, this guidance offers an approach for decision-making regarding antivirals, informed by available data. As evidence continues to evolve rapidly, the need for updates to the guidance is anticipated.

Degradation of hydroxychloroquine by electrochemical advanced oxidation processes

In this work, the degradation of hydroxychloroquine (HCQ) drug in aqueous solution by electrochemical advanced oxidation processes including electrochemical oxidation (EO) using boron doped diamond (BDD) and its combination with UV irradiation (photo-assisted electrochemical oxidation, PEO) and sonication (sono-assisted electrochemical oxidation, SEO) was investigated. EO using BDD anode achieved the complete depletion of HCQ from aqueous solutions in regardless of HCQ concentration, current density, and initial pH value. The decay of HCQ was more rapid than total organic carbon (TOC) indicating that the degradation of HCQ by EO using BDD anode involves successive steps leading to the formation of organic intermediates that end to mineralize. Furthermore, the results demonstrated the release chloride (Cl-) ions at the first stages of HCQ degradation. In addition, the organic nitrogen was converted mainly into NO3 - and NH4 + and small amounts of volatile nitrogen species (NH3 and NOx). Chromatography analysis confirmed the formation of 7-chloro-4-quinolinamine (CQLA), oxamic and oxalic acids as intermediates of HCQ degradation by EO using BDD anode. The combination of EO with UV irradiation or sonication enhances the kinetics and the efficacy of HCQ oxidation. PEO requires the lowest energy consumption (EC) of 63 kWh/m3 showing its cost-effectiveness. PEO has the potential to be an excellent alternative method for the treatment of wastewaters contaminated with HCQ drug and its derivatives.

A case of Melkersson-Rosenthal syndrome with endocrine disorders: Extraordinary efficiency of hydroxychloroquine and mechanism hypothesis

BACKGROUND AND PURPOSE

Melkersson-Rosenthal syndrome (MRS) is a rare neuro-mucocutaneous disease. In addition to the traditional clinical triad, there is also a diversity of clinical signs, and it may be related to other systemic diseases.

METHODS

In the present study, we report a case of MRS with endocrine disorders that exhibits extraordinary therapeutic efficiency by using hydroxychloroquine (HCQ), explore whether there is an internal connection between MRS and endocrine disorders, and discuss the mechanism of the therapeutic efficiency of using HCQ. The hypothesis proposed for the first time is that MRS may essentially be a systemic granulomatous disease.

RESULTS

The physical examination revealed orofacial swelling and fissured tongue. The histopathologic examination showed epithelioid granulomas. Combined with the other examination, this case was diagnosed as incomplete MRS. HCQ and local drugs were introduced. The patient achieved clinical recovery and psychological cure by the 18-week follow-up, and the 1-year follow-up found no reactivation of MRS. Moreover, the levels of cortisol and adrenocorticotropic were within normal ranges.

CONCLUSIONS

After the drug therapy was targeted at granuloma, not only did all of the symptoms related to MRS disappear, but the endocrine system also returned to normal. It is speculated that the endocrine disorder in this patient may be related to MRS. We further propose the first-time hypothesis that MRS may essentially be a systemic granulomatous disease. It provides a new medication method with high-level efficiency.

Cytotoxicity Evaluation of Chloroquine and Hydroxychloroquine in Multiple Cell Lines and Tissues by Dynamic Imaging System and Physiologically Based Pharmacokinetic Model

Chloroquine (CQ) and hydroxychloroquine (HCQ) have been challenged in treating COVID-19 patients and still under debate due to the uncertainty regarding the effectiveness and safety, and there is still lack of the systematic study on the toxicity of these two drugs. To further uncover the toxicity profile of CQ and HCQ in different tissues, we evaluated the cytotoxicity of them in eight cell lines and further adopted the physiologically based pharmacokinetic models to predict the tissue risk, respectively. Retina, myocardium, lung, liver, kidney, vascular endothelium, and intestinal epithelium originated cells were included in the toxicity evaluation of CQ and HCQ, respectively. The proliferation pattern was monitored in 0–72 h by IncuCyte S3. CC50 and the ratio of tissue trough concentrations to CC50 (R_TTCC) were brought into predicted toxicity profiles. Compared to CQ, HCQ was found to be less toxic in six cell types except Hep3B and Vero cells. In addition, R_TTCC was significantly higher in CQ treatment group compared to HCQ group, which indicates relative safety of HCQ. To further simulate the situation of the COVID-19 patients who suffered the dyspnea and hypoxemia, we also tested the cytotoxicity upon hypoxia and normoxia (1, 5 vs. 21% O₂). It was found that the cytotoxicity of CQ was more sensitive to hypoxia compared with that of HCQ, particularly in liver originated cells. Both CQ and HCQ showed cytotoxicity in time-dependent manner which indicates the necessity of short period administration clinically.

Spectral-Domain Optical Coherence Tomography Is More Sensitive for Hydroxychloroquine-Related Structural Abnormalities Than Short-Wavelength and Near-Infrared Autofluorescence

Purpose

To analyze the appearance of structural abnormalities due to hydroxychloroquine (HCQ) toxicity by spectral-domain optical coherence tomography (SD-OCT) and short-wavelength autofluorescence (SW-AF) and near-infrared fundus autofluorescence (NIR-AF) imaging.

Methods

This retrospective cohort study included 88 eyes from 44 patients who had a history of or were currently taking HCQ. SD-OCT, SW-AF, and NIR-AF images were analyzed by two independent graders for the detection of HCQ-associated abnormalities.

Results

Sixty eyes (30 patients, 68%) presented with no abnormalities for either imaging modality. Twenty eyes (10 patients, 23%) presented with parafoveal abnormalities (ellipsoid zone attenuation and/or interdigitation zone continuity loss) in SD-OCT scans but with qualitatively normal SW-AF and NIR-AF images. Eight eyes (four patients, 9%) presented with bull's-eye maculopathy in SW-AF and NIR-AF images, with corresponding outer retinal structures disrupted parafoveally in SD-OCT scans ("flying saucer" sign). No patients presented with normal SD-OCT scans and concurrent abnormalities in SW-AF or NIR-AF images.

Conclusions

SD-OCT was more sensitive in detecting structural abnormalities than either SW-AF or NIR-AF imaging, suggesting its superiority as a screening imaging modality for HCQ toxicity. Maculopathy and abnormalities in the retinal pigment epithelium from HCQ toxicity can be appreciated in both SW-AF and NIR-AF images.

Translational Relevance

Although debate exists regarding the best imaging modalities for screening patients for potential HCQ toxicity, our study supports the use of SD-OCT over both SW-AF and NIR-AF imaging as a screening modality.

Hydroxychloroquine treatment for Alopecia Universalis: Report of six cases

Recent reports indicate that hydroxychloroquine is a potential new treatment option for alopecia universalis; thus, we aimed to report on the safety and efficacy of hydroxychloroquine in 6 patients with refractory alopecia universalis that were treated with 400 mg/d continuously for ≥6 months. The treatment outcome was retrospectively evaluated using the Severity of Alopecia Tool (SALT), and at the end of 6 months, patients with a ≥50% decrease in the SALT score were considered as strong responders, a 5%-50% decrease as intermediate responders and a <5% decrease as non-responders. The present findings indicate that hydroxychloroquine is not an effective treatment since in 5 of the 6 patients it was discontinued at the end of 6 months due to lack of hair regrowth, whereas only a 6-year-old boy responded with a SALT score change of 8% after the 12th month.

Demodex positive discoid lupus erythematosus: Is it a separate entity or an overlap syndrome?

Discoid lupus erythematosus (DLE) is a chronic inflammatory erythematous skin disease that can be triggered by several factors. Rosacea is another skin disease that causes facial redness and tenderness. Demodex mites have been reported in rosacea and DLE patients commonly in the literature. These two diseases can be seen concomitant, mimic each other clinically and share common possible etiologic factors. To assess demodex mite infestation in both clinical and histopathological findings in DLE patients. We retrospectively evaluated the files of 42 patients with DLE who had been diagnosed DLE based on clinical and histopathological findings between August 2018 and August 2019. Demodex positivity was detected 50% of patients (n = 21). Neutrophile percentages in the dermal and perivascular area were higher in the demodex positive patients (4.43%) than in the Demodex negative patients (2.19%). The intensity of demodex mites correlated positively with dermal neutrophile percentages. ANA was negative in 29 patients (69%) and positive in 13 patients (31%). Anti-dsDNA was negative in serology and follicular plugging was positive in histopathology in all 42 patients (100%). This was a retrospective study. DLE and rosacea share common features in etiopathogenesis and clinical presentation. Inflammation and exacerbations caused by the demodex mites may increase the clinical severity of DLE. Although the position of demodex mites in DLE etiopathogenesis is not known exactly, the presence of high demodex in DLE patients has been determined. Standard skin surface biopsy can be a routine procedure for the evaluation of DLE patients in daily clinical practice.

Cytotoxicity Evaluation of Chloroquine and Hydroxychloroquine in Multiple Cell Lines and Tissues by Dynamic Imaging System and Physiologically Based Pharmacokinetic Model

Chloroquine (CQ) and hydroxychloroquine (HCQ) have been challenged in treating COVID-19 patients and still under debate due to the uncertainty regarding the effectiveness and safety, and there is still lack of the systematic study on the toxicity of these two drugs. To further uncover the toxicity profile of CQ and HCQ in different tissues, we evaluated the cytotoxicity of them in eight cell lines and further adopted the physiologically based pharmacokinetic models to predict the tissue risk, respectively. Retina, myocardium, lung, liver, kidney, vascular endothelium, and intestinal epithelium originated cells were included in the toxicity evaluation of CQ and HCQ, respectively. The proliferation pattern was monitored in 0-72 h by IncuCyte S3. CC50 and the ratio of tissue trough concentrations to CC50 (R_TTCC) were brought into predicted toxicity profiles. Compared to CQ, HCQ was found to be less toxic in six cell types except Hep3B and Vero cells. In addition, R_TTCC was significantly higher in CQ treatment group compared to HCQ group, which indicates relative safety of HCQ. To further simulate the situation of the COVID-19 patients who suffered the dyspnea and hypoxemia, we also tested the cytotoxicity upon hypoxia and normoxia (1, 5 vs. 21% O₂). It was found that the cytotoxicity of CQ was more sensitive to hypoxia compared with that of HCQ, particularly in liver originated cells. Both CQ and HCQ showed cytotoxicity in time-dependent manner which indicates the necessity of short period administration clinically.

Dermatologists' Adherence to the Latest Recommendations for Screening of Hydroxychloroquine Retinopathy in Saudi Arabia: Cross-Sectional Study

Background

Hydroxychloroquine (HCQ) has been used to manage many inflammatory skin conditions. Nevertheless, retinopathy continues to be its most significant adverse effect. The American Academy of Ophthalmology (AAO) recommends baseline ophthalmologic screening in the first year of HCQ treatment. However, a recent study found an inadequate awareness of the recommendations. Furthermore, limited data are available regarding the implementation of the recommendations among dermatologists.

Objective

The aim of this study was to assess dermatologists’ adherence to recommendations pertaining to their current practice regarding HCQ toxicity detection.

Methods

A self-administrated questionnaire was distributed between February 2 and May 4, 2018, among members of the Saudi Society of Dermatology. The questionnaire comprised demographic-related questions and questions pertaining to each physician’s routine practice about the follow-up of HCQ-treated patients.

Results

A total of 76 dermatologists completed the questionnaire. We achieved a response rate of 62.54%. More than half (43/76, 56%) of the dermatologists were male. Furthermore, more than half (41/76, 53%) of them reported treating 1 to 3 patients with HCQ during the last year. Furthermore, two-thirds (47/76, 61%) of them reported screening patients before initiating HCQ treatment. Regarding follow-up recommendations, 59% (45/76) of dermatologists reported yearly after starting treatment for no-risk patients, whereas 94% (72/76) reported “yearly within 5 years of treatment” for at-risk patients. Data were considered significant at P<.05. All analyses were performed using SPSS, version 20 (IBM).

Conclusions

Dermatologists in Saudi Arabia are not well informed about some aspects of the latest recommendations regarding screening for HCQ toxicity in terms of tests, follow-up timing, cessation of the drug, and causative agents. Therefore, we recommend conducting more studies in Saudi Arabia to determine the adherence of more physicians to the AAO recommendations. Furthermore, patient education regarding HCQ toxicity and increased patient awareness are recommended for effective and safe HCQ use.

Hydroxychloroquine in dermatology: New perspectives on an old drug

Hydroxychloroquine is an age-old drug whose use as an immunomodulatory agent with a low side-effect profile continues to expand. We present a review of this drug including recently updated prescribing recommendations and a summary of its clinical application in dermatology. A maximum daily dose of 5.0 mg/kg based on actual body weight and no greater than 400 mg is advised in order to reduce the risk of retinopathy, which is potentially permanent and has an estimated prevalence of 7.5% at 5 years on standard dosing. Baseline ophthalmologic assessment followed by annual screening after 5 years is recommended; however, closer monitoring should be considered in the setting of existing retinopathy, a cumulative dose > 1000 g or renal dysfunction. Hydroxychloroquine is now considered to be safe in pregnancy, and routine glucose-6-phosphate dehydrogenase (G6PD) deficiency testing is not required. Smoking can significantly decrease its efficacy although the reason is still uncertain. Hydroxychloroquine appears to also demonstrate antineoplastic and cardioprotective benefits.

Treatment of morphea with hydroxychloroquine: A retrospective review of 84 patients at Mayo Clinic, 1996-2013

BACKGROUND

Few studies support treating morphea (localized scleroderma) with hydroxychloroquine.

OBJECTIVE

To assess the efficacy of hydroxychloroquine treatment of morphea.

METHODS

We conducted a retrospective study of 84 patients who had morphea and were treated with hydroxychloroquine monotherapy for at least 6 months at our institution from 1996 through 2013. The median times to initial and maximal responses were assessed.

RESULTS

Of the 84 patients (median age at diagnosis, 29.5 years), 65 (77.4%) were female, 36 (42.9%) had a complete response to hydroxychloroquine, 32 (38.1%) had a partial response greater than 50%, 10 (11.9%) had a partial response less than or equal to 50%, and 6 (7.1%) had no response. The median time to initial response was 4 months, and the median time to maximal response was 12 months. Ten patients (11.9%) experienced adverse effects from hydroxychloroquine; the most common adverse effect was nausea (6 patients).

LIMITATIONS

Retrospective study.

CONCLUSIONS

Hydroxychloroquine is a valuable treatment for morphea because of its high response rate and low rate of adverse effects; however, prospective studies are needed to determine its true efficacy.

[Prevalence of hydroxychloroquine-induced side-effects in dermatology patients: A retrospective survey of 102 patients]

AIM

Our aim was to assess the prevalence of adverse effects (AEs) pertaining to the use and withdrawal of hydroxychloroquine (HCQ) in dermatological outpatients.

PATIENTS AND METHODS

We conducted a retrospective study between January 2013 and June 2014 that included consecutive patients currently or previously receiving HCQ seen in our department. AEs were collated using a standardized questionnaire and validated by clinical and laboratory examination. Drug causality was evaluated using the updated French drug reaction causality assessment method. The main evaluation criterion was the prevalence of AEs in which HCQ had an intrinsic imputability score of I>2.

RESULTS

We included 102 patients (93 of whom were women, with a median age of 44.5; range: 22-90years). HCQ was given for cutaneous lupus in most cases (n=70). At least one AE was reported for 55 patients. Among the 91 reported AEs, 59 (65%) had an HCQ intrinsic imputability score I>2. AEs were responsible for permanent HCQ discontinuation in 19 cases. Of these, 8 were unrelated to HCQ based on imputability score. The most common AEs associated with HCQ were gastrointestinal and cutaneous signs. Of the 8 patients diagnosed with retinopathy, only 3 were confirmed after reevaluation.

CONCLUSION

AEs associated with HCQ were reported for over 50% of patients and were responsible for permanent HCQ discontinuation in one-third of cases. A more in-depth evaluation of imputability seems necessary, particularly regarding ophthalmological symptoms, since in two thirds of cases the reasons for discontinuation were not related to HCQ.

Hydroxychloroquine retinal toxicity in two patients with dermatological conditions

Two patients with dermatological conditions developed retinal toxicity after treatment with hydroxychloroquine that exceeded dosing recommendations. There is no treatment for hydroxychloroquine retinal toxicity and associated visual loss, so appropriate monitoring is imperative. All members of a patient's multidisciplinary team should be aware of the ocular risks of hydroxychloroquine, the importance of dosing within recommended guidelines and appropriate monitoring in reducing the risk of visual loss.

Hydroxychloroquine Inhibits the Differentiation of Th17 Cells in Systemic Lupus Erythematosus

Objective.

Hydroxychloroquine (HCQ) is a commonly used medicine for the treatment of systemic lupus erythematosus (SLE), and Th17 cells are closely related to the pathogenesis of SLE. However, the role and mechanism of HCQ on Th17 cell differentiation in SLE is not clearly understood. Here, we investigate the effect of HCQ on Th17 cell differentiation bothin vitroand in patients with SLE.

Methods.

Twenty-five patients with SLE were divided into 2 treatment groups: prednisone alone and HCQ plus prednisone. Interleukin 17 (IL-17) expression was analyzed by ELISA and real-time (RT)-PCR. Th17 were measured in patients with SLE by flow cytometry before and after HCQ treatment.In vitro, naive T cells were cultured in Th17-inducing conditions with or without HCQ. Cell differentiation and IL-17 expression were analyzed. Finally, transcriptome sequencing identified differential gene expression between naive T cells and induced Th17 cells.

Results.

In patients, HCQ plus prednisone treatment inhibited IL-17 production, gene expression, and Th17 cell differentiation.In vitro, HCQ inhibited Th17 cell proliferation and differentiation, as well as IL-17 production. Five microRNA were significantly different in Th17 cells compared with naive T cells, and HCQ treatment reversed this effect.In vivo, microRNA-590 (miR-590) was verified and was significantly decreased in Th17 cells, compared with naive T cells from lupus-prone mice. Moreover, miR-590 was increased in patients treated with HCQ plus prednisone.

Conclusion.

HCQ inhibited Th17 cell differentiation and IL-17 production bothin vitroand in patients with SLE. Our study provides additional evidence for HCQ as a treatment for SLE.