Botulinum toxin for refractory Raynaud's phenomenon: A "how to" guide for pediatric patients.

Raynaud's phenomenon describes symptoms caused by digital vascular spasm and is classically induced by cold exposure. Severe cases can result in ulceration, necrosis, and digital autoamputation. When standard and adjunctive medical therapies fail or are contraindicated, botulinum toxin A (BTX-A) is an effective treatment option that can be added to existing regimens and should be considered before utilizing rescue therapies associated with higher risk and often higher cost. This report describes our technique, highlights considerations relevant to pediatric patients, and provides photos and videos of the procedure performed on a 16-year-old girl.

Botulinum Toxins for the Treatment of Raynaud Phenomenon: A Systematic Review With Meta-analysis.

OBJECTIVE: Botulinum toxin (Btx) therapy has emerged as a potential treatment for patients with Raynaud phenomenon (RP) in recent years. This study aimed to investigate the efficacy and safety of Btx treatment for RP. METHODS: Databases of PubMed, EMBASE, Web of Science, and the Cochrane Central Register of Controlled Trials were searched from their inception up to August 2022. Studies that reported Btx use for the treatment of RP were included. A meta-analysis was conducted for the Shortened version of the Disabilities of the Arm, Shoulder, and Hand (Quick DASH) score and visual analog scale pain score using a random-effects model. RESULTS: Thirteen full-text studies were included. The pooled standard mean changes for the visual analog scale pain score and QuickDASH score were -3.82 (95% confidence interval, -6.62 to -1.02) and 0.83 (95% confidence interval, -1.47 to -0.19), respectively. The 2 most common complications were injection site pain and intrinsic hand weakness. CONCLUSIONS: The effect of Btx treatment on RP is promising based on current evidence. Nevertheless, more studies and randomized clinical trials with larger sample sizes are needed to confirm the current results.

[What's new in the management of systemic sclerosis]. / Nouveautés dans la prise en charge de la sclérodermie systémique.

This review of the literature highlights the results of the recent randomized controlled trials about the management of systemic sclerosis (SSc) and its complications. The latest randomized studies have failed to demonstrate the utility against placebo of the injections of botulinum toxin A to achieve a better control of Raynaud's phenomenon and the efficacy of the adipose-derived cell transplantation for the treatment of hand dysfunction. Rituximab allows a significant improvement of cutaneous induration. The injections of mesenchymal stromal cells are well tolerated and should encourage future randomized trials to evaluate their efficacy. Finally, nintedanib and tocilizumab allow a reduction in the rate of decline of lung function, as well as a possible stabilization with tocilizumab.

Cet article expose les résultats des essais randomisés et contrôlés récents concernant la prise en charge de la sclérodermie systémique (SSc) et ses complications. Les études discutent l'utilité des injections de la toxine botulinique pour le contrôle du phénomène de Raynaud, et des injections de cellules dérivées du tissu adipeux pour améliorer la fonctionnalité de la main. Le rituximab permet une amélioration significative de l'induration cutanée, et les injections de cellules stromales mésenchymateuses, en plus d'être bien tolérées, ouvrent la voie à d'éventuels essais randomisés en vue d'évaluer leur efficacité. Finalement, le nintédanib et le tocilizumab permettent une réduction du taux de déclin de la fonction pulmonaire, jusqu'à une éventuelle stabilisation de cette dernière observée avec le tocilizumab.

Sudden winter iloprost withdrawal in scleroderma patients during COVID-19 pandemic.

INTRODUCTION: Intravenous iloprost is currently recommended in the treatment of Raynaud's phenomenon (RP) refractory to oral therapy and of digital ulcers (DUs) related to systemic sclerosis (SSc). In real-life practice there is a huge heterogeneity about the Iloprost regimens used. METHODS: A survey was carried out on SSc patients that interrupted Iloprost infusion to compare acral vascular symptoms just before Iloprost withdrawal and just after the missed infusion. Severity, and frequency of RP, new DUs onset or aggravation of those pre-existing were reported. Last available capillaroscopic images were also evaluated. RESULTS: The analysis includes 50 patients. After iloprost withdrawal, 11 patients reported a RP worsening because of enhanced intensity (p = 0.007). Only 8 patients of them also complained of an increased frequency (p = 0.07). None of the patients experienced digital ulcers for the first-time during quarantine. Among the 27 patients with a history of digital ulcers, 9 reported worsening and 7 recurrence of DUs. Overall, 17 patients (34.0 %) complained of a worsening of SSc vascular acral manifestations, namely RP or DUs. Reduced capillary density was associated with RP worsening, in particular, each unit increase of capillary density corresponds to an average 44 % decrease in the odds of RP worsening (OR 0.56, CI 95 % 0.36-0.97, p = 0.037). As for RP worsening, the aggravation of DU was associated with a lower capillary density. CONCLUSIONS: Low capillary density can predict a worsening of both RP and DUs in controlled quarantine conditions within a month after iloprost discontinuation in SSc patients.

Systemic sclerosis in adults. Part II: management and therapeutics.

The management of systemic sclerosis (SSc) is complex, evolving, and requires a multidisciplinary approach. At diagnosis and throughout the disease course, clinical assessment and monitoring of skin involvement is vital using the modified Rodnan Skin Score, patient-reported outcomes, and new global composite scores (such as the Combined Response Index for Systemic Sclerosis, which also considers lung function). Immunomodulation is the mainstay of skin fibrosis treatment, with mycophenolate mofetil considered first line. Meanwhile vasculopathy-related manifestations (Raynaud's phenomenon, digital ulcers) and calcinosis, require general measures combined with specific pharmacologic (calcium-channel blockers, phosphodiesterase type 5 inhibitors, and prostanoids), nonpharmacologic (digital sympathectomy and botulinum toxin injections), and often multifaceted, management approaches. Patients should be screened at the time of diagnosis specifically for systemic manifestations and then regularly thereafter, with appropriate treatment. Numerous targeted therapeutic options for SSc, including skin fibrosis, are emerging and include B-cell depletion, anti-interleukin 6, Janus kinase, and transforming growth factor ß inhibition. This second article in the continuing medical education series discusses these key aspects of SSc assessment and treatment, with particular focus on skin involvement. It is vital that dermatologists play a key role in the multidisciplinary approach to SSc management.

The efficacy of botulinum toxin A in the treatment of Raynaud's phenomenon in systemic sclerosis: A randomized self-controlled trial.

The current conservative and surgical treatments are not fully effective and have complications for Raynaud's phenomenon (RP) secondary to systemic sclerosis (SSc). Botulinum toxin A (BTX-A) can be used to manage RP, but the literature mostly includes case reports and case series. Thus, we performed a randomized controlled trial to explore the efficacy of BTX-A in the treatment of RP secondary to SSc. Sixteen patients with RP secondary to SSc were recruited. One hand was randomly included in the BTX-A group and the other as control. Both hands were tested before treatment and 4 weeks later using qualitative and quantitative dermatoscopic assessments and the cold water test. Reynolds score (from 6.7 ± 4.0 to 2.9 ± 3.7, p < 0.001), Tbase (from 25.8 ± 3.0°C to 27.9 ± 2.1°C, p = 0.031) and Tchange (from 2.1 ± 1.2°C to 4.5 ± 2.1°C, p < 0.001) in the experimental group were improved, while there were no improvements in Tbase and Tchange in the control group. In the experimental group, the sum of the six dermoscopic parameters was improved after treatment (from 4.00 (3.00, 5.75) to 3.00 (2.00, 5.00), p = 0.002); the nailfold capillary pattern staging was also improved (from 2.00 (2.00, 3.00) to 2.00 (1.00, 3.00), p = 0.004). There were no improvements in the dermoscopic assessment in the control group. None of the patients reported adverse reactions such as infection, hematoma, hand muscle weakness, allergic reaction and nerve injury. In conclusion, local injection BTX-A to treat RP secondary to SSc might be safe and effective.

Vasodilators for primary Raynaud's phenomenon.

BACKGROUND: Numerous agents have been suggested for the symptomatic treatment of primary Raynaud's phenomenon. Apart from calcium channel blockers, which are considered to be the drugs of choice, evidence of the effects of alternative pharmacological treatments is limited. This is an update of a review first published in 2008. OBJECTIVES: To assess the effects of drugs with vasodilator effects on primary Raynaud's phenomenon as determined by frequency, severity, and duration of vasospastic attacks; quality of life; adverse events; and Raynauds Condition Score. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases, and the World Health Organization International Clinical Trials Registry Platform and the ClinicalTrials.gov trial register to November 16, 2020. SELECTION CRITERIA: We included randomized controlled trials evaluating effects of oral, intravenous, and topical formulations of any drug with vasodilator effects on subjective symptoms, severity scores, and radiological outcomes in primary Raynaud's phenomenon. Treatment with calcium channel blockers was not assessed in this review, nor were these agents compared. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies for inclusion, assessed studies using the Cochrane "Risk of bias" tool, and extracted study data. Outcomes of interest included frequency, severity, and duration of attacks; quality of life (QoL); adverse events (AEs); and the Raynaud Condition Score (RCS). We assessed the certainty of the evidence using GRADE. MAIN RESULTS: We identified seven new studies for this update. In total, we included 15 studies involving 635 participants. These studies compared different vasodilators to placebo. Individual studies used different methods and measures to report different outcomes. Angiotensin-converting enzyme (ACE) inhibitors Combining data from three studies revealed a possible small increase in the frequency of attacks per week after treatment (captopril or enalapril) compared to placebo (mean difference [MD] 0.79, 95% confidence interval [CI] 0.43 to 1.17; low-certainty evidence). There was no evidence of a difference between groups in severity of attacks (MD -0.17, 95% CI -4.66 to 4.31; 34 participants, 2 studies; low-certainty evidence); duration of attacks (MD 0.54, 95% CI -2.42 to 1.34; 14 participants, 1 study; low-certainty evidence); or AEs (risk ratio [RR] 1.35, 95% CI 0.67 to 2.73; 46 participants, 3 studies; low-certainty evidence). QoL and RCS were not reported. Alpha blockers Two studies used alpha blockers (buflomedil or moxisylyte). We were unable to combine data due to the way results were presented. Buflomedil probably reduced the frequency of attacks compared to placebo (MD -8.82, 95% CI -11.04 to -6.60; 31 participants, 1 study; moderate-certainty evidence) and may improve severity scores (MD -0.41, 95% CI -0.62 to -0.30; moderate-certainty evidence). With moxisylyte, investigators reported fewer attacks (P < 0.02), less severe symptoms (P < 0.01), and shorter duration of attacks, but the clinical relevance of these results is unclear. No evidence of a difference in AEs between buflomedil and placebo groups was noted (RR 1.41, 95% CI 0.27 to 7.28; 31 participants, 1 study; moderate-certainty evidence). More AEs were observed in participants in the moxisylyte group than in the placebo group. Prostaglandin/prostacyclin analogues One study compared beraprost versus placebo. There was no evidence of benefit for frequency (MD 2.00, 95% CI -0.35 to 4.35; 118 participants, low-certainty evidence) or severity (MD -0.06, 95% CI -0.34 to 0.22; 118 participants, low-certainty evidence) of attacks. Overall, more AEs were noted in the beraprost group (RR 1.59, 95% CI 1.05 to 2.42; 125 participants; low-certainty evidence). This study did not report on duration of attacks, QoL, or RCS. Thromboxane synthase inhibitors One study compared a thromboxane synthase inhibitor (dazoxiben) versus placebo. There was no evidence of benefit for frequency of attacks (MD 0.8, 95% CI -1.81 to 3.41; 6 participants; very low-certainty evidence). Adverse events were not reported in subgroup analyses of participants with primary Raynaud's phenomenon, and the study did not report on duration of attacks, severity of symptoms, QoL, or RCS. Selective serotonin reuptake inhibitors One study compared ketanserin with placebo. There may be a slight reduction in the number of attacks per week with ketanserin compared to placebo (MD -14.0, 95% CI -27.72 to -0.28; 41 participants; very low-certainty evidence) and reduced severity score (MD -133.00, 95% CI -162.40 to -103.60; 41 participants; very low-certainty evidence). There was no evidence that ketanserin reduced the duration of attacks (MD -4.00, 95% CI -14.82 to 6.82; 41 participants; very low-certainty evidence), or that AEs were increased in either group (RR 1.54, 95% CI 0.89 to 2.65; 41 participants; very low-certainty evidence). This study did not report on QoL or RCS. Nitrate/nitrate derivatives Four studies compared topical treatments of nitroglycerin or glyceryl trinitrate versus placebo, each reporting on limited outcomes. Meta-analysis demonstrated no evidence of effect on frequency of attacks per week (MD -1.57, 95% CI -4.31 to 1.17; 86 participants, 2 studies; very low-certainty evidence). We were unable to pool any data for the remaining outcomes. Phosphodiesterase inhibitors Three studies compared phosphodiesterase inhibitors (vardenafil, cilostazol or PF-00489791) to an equivalent placebo. Results showed no evidence of a difference in frequency of attacks (standardized MD [SMD] -0.05, 95% CI -6.71 to 6.61; 111 participants, 2 studies; low-certainty evidence), severity of attacks (MD -0.03, 95% CI -1.04 to 0.97; 111 participants, 2 studies; very low-certainty evidence), duration of attacks (MD -1.60, 95% CI -7.51 to 4.31; 73 participants, 1 study; low-certainty evidence), or RCS (SMD -0.8, 95% CI -1.74 to 0.13; 79 participants, 2 studies; low-certainty evidence). Study authors reported that 35% of participants on cilostazol complained of headaches, which were not reported in the placebo group. PF-00489791 caused 34 of 54 participants to experience AEs versus 43 of 102 participants receiving placebo (RR 1.49). Headache was most common, affecting 14 participants (PF-00489791) versus nine participants (placebo). AUTHORS' CONCLUSIONS: The included studies investigated several different vasodilators (topical and oral) for treatment of primary Raynaud's phenomenon. Small sample sizes, limited data, and variability in outcome reporting yielded evidence of very low to moderate certainty. Evidence is insufficient to support the use of vasodilators and suggests that vasodilator use may even worsen disease.

Targeted high concentration botulinum toxin A injections in patients with Raynaud's phenomenon: a retrospective single-centre experience.

Raynaud's phenomenon is a vasospastic condition affecting hands and feet which may lead to rest pain, ischemic ulcers and gangrene. Botulinum toxin A has been shown to improve peripheral circulation and relieve vasospastic symptoms. Our aim was to assess our treatment outcomes following Botulinum toxin A injections in patients with Raynaud's phenomenon and to explore the importance of toxin concentration and injection sites. Retrospective chart review of patients with primary and secondary Raynaud's syndrome treated with Botulinum toxin A injections and a literature review was conducted. The toxin dose, injection sites, symptom relief, healing of ulcers and complications were assessed. A total of 30 treatment episodes over a 7½ year period were included. All patients had failed medical management. Botulinum toxin A injection was injected primarily in the vicinity of the palmar digital neurovascular bundle. The average total Botulinum toxin A dose injected was 156 U and the concentration was 50 U/ml. All patients reported an improvement in symptoms and healing of digital ulcers. One patient reported a temporary muscle weakness. Six patients had a single treatment episode with long term benefit. Systemic sclerosis patients had an average of 6-month interval between treatment episodes. Higher doses of Botulinum toxin A has been well tolerated with no long term adverse effects. Our study shows that targeted low volume higher concentration Botulinum toxin A injections are effective in treating Raynaud's phenomenon.

Botulinum Toxin A Treatment for Primary and Secondary Raynaud's Phenomenon in Teenagers.

BACKGROUND: Raynaud's phenomenon (RP) is a clinical syndrome characterized by recurrent episodes of digital vasospasm triggered by exposure to physical and chemical agents or emotional stress. Although many pharmacologic treatments have been tested, there is still no cure or gold standard therapy. Botulinum toxin treatment has been proved to reduce pain and increase arterial blood flow in treated hands of adult patients with RP. OBJECTIVE: The aim of this study is to evaluate the efficacy of botulinum toxin A on younger than 18-year-old patients with primary and secondary RP. MATERIALS AND METHODS: A single-center prospective study was performed, including 8 patients aged 14 to 17 years who were clinically diagnosed with primary or secondary RP. BTX was injected into each hand without sedation or anesthetic blockade. The primary outcome was pain reduction after BTX injection. Pain intensity was evaluated at baseline and in the first follow-up. Secondary outcomes included variations in the number and severity of RP episodes after the BTX injection. RESULTS: All patients stated significant pain reduction and decreased cold sensitivity, except one patient who did not feel any changes. No patients reported any loss of strength on thumb-index finger. CONCLUSION: BTX injection is a simple, noninvasive, and cost-effective treatment alternative, offering an important nonsurgical therapeutic option for the pediatric population. It could also help optimize the dose of other treatments used in these patients. The most commonly observed positive effect is a reduction in the pain associated with RP attacks. Further studies are needed to confirm these results.

OnabotulinumtoxinA for Systemic Sclerosis-associated Raynaud's Phenomenon: A Multi-Institutional Study on Accessibility and Effectiveness.

Raynaud’s phenomenon (RP), a common presenting symptom of systemic sclerosis (SSc), is a painful and debilitating condition of the digits caused by increased vascular reactivity.1,2.

Botulinum Toxin for the Treatment of Intractable Raynaud Phenomenon.

Raynaud phenomenon (RP) is a condition causing vasospasm in the fingers and toes of patients that can have a significant negative impact on quality of life. This can lead to pain, ulceration, and possible loss of digits. Several pharmacological options are available for treatment. However, RP can often be refractory to traditional modalities, leaving surgery or injections as the next available options. This article provides a review and update on the use of botulinum toxin as an effective therapy for the treatment of RP refractory to medical management.

Drug repurposing in Raynaud's phenomenon through adverse event signature matching in the World Health Organization pharmacovigilance database.

AIMS: Several pharmacological treatments are recommended for Raynaud's phenomenon (RP) secondary to systemic sclerosis, but they only have modest efficacy. A way to efficiently identify new drugs is drug repurposing, which can be based on signature matching. The signature could be derived from chemical structures, pharmacological affinity or adverse event profiles. We propose to use the World Health Organization (WHO) pharmacovigilance database to generate repositioning hypotheses for treatments of RP through adverse event signature matching. METHODS: We first screened all drugs associated with at least 1 case of erythromelalgia, an adverse effect opposite to RP. In parallel, to define the adverse event signature of drugs recommended in secondary RP from the WHO pharmacovigilance database, we selected the 14 most representative adverse drug reactions (ADRs). Lastly, we performed a hierarchical cluster analysis to identify drugs with similar ADR signature to vasodilatory drugs used in RP. RESULTS: In total, 179 drugs were associated with erythromelalgia; they were related to 860 334 adverse events representative of RP drugs in the WHO pharmacovigilance database. Hierarchical cluster analysis allowed identification of 6 clusters. The most stable cluster contained 7 drugs, among which 5 are recommended in secondary RP, or pertain to the same drug class: epoprostenol, nifedipine, nicardipine, lacidipine and israpidine. The 2 remaining drugs were alemtuzumab and fumaric acid. CONCLUSION: Our ADR signature matching approach suggests that alemtuzumab and fumaric acid could be effective treatments of secondary RP. The latter is currently being investigated as a treatment of pulmonary hypertension in systemic sclerosis.

Botulinum toxin type A in the treatment of Raynaud's phenomenon.

Raynaud's phenomenon is a vasospastic disorder clinically characterized by cold or stress-induced discoloration of the skin, pain and ulcers of the fingers or toes. Although this phenomenon might be self-limiting, there is a subgroup of patients requiring a therapeutic approach. The majority of patients do well on conservative measures; however, there is also a subgroup requiring systemic treatment. The efficacy of these systemic treatments is currently not thoroughly investigated. Furthermore, no uniform guidelines exist regarding the choice for a treatment option. In the past several years, several reports have shown the benefits of botulinum toxin for the treatment of Raynaud's phenomenon. In this case series, we report our experience with botulinum toxin type A in the treatment of Raynaud's phenomenon.

Ischemic ulcers of the toes secondary to Raynaud's phenomenon in a child successfully treated with botulinum toxin.

Raynaud's phenomenon (RP) is an episodic vasospastic response to cold or emotional stress causing color changes and pain. These attacks can lead to digital ischemia, ulcers, and gangrene. Severe and refractory RP in children is a therapeutic challenge for clinicians because there are no standardized treatment protocols for these patients. We present a case of RP involving the toes of a child successfully treated with botulinum toxin A.

The Use of Ultrasound Guidance for the Treatment of Raynaud Disease of the Hand With Botulinum Toxin.

BACKGROUND: This study sought to examine the feasibility and effectiveness of the use of ultrasound (US) as a clinical adjunct in the delivery of botulinum toxin for the treatment of Raynaud disease of the hand. METHODS: One cadaver hand was injected with a colored simulation material using the current traditional surface anatomy approach, whereas an additional cadaver hand was injected using US guidance. The hands were dissected and areas of distribution of the simulation material were evaluated. Five patients diagnosed with Raynaud disease were treated with botulinum toxin using US guidance and data using the Patient-Reported Outcomes Measurement Information System Upper Extremity were collected. RESULTS: The cadaver hand injected with a colored simulation material using US guidance demonstrated significantly reduced surface area of muscle infiltrated compared with the cadaver hand injected using the traditional surface anatomy approach (16 cm vs 37 cm, P < 0.001).All 5 patients treated with botulinum toxin using US guidance reported significant improvement in symptoms and function after injection (P < 0.05), where zero patients reported intrinsic hand weakness. CONCLUSIONS: The use of US significantly improves the accuracy of delivery of a surrogate dye in a cadaver model of Raynaud disease, whereas its use clinically results in at least as effective a treatment as the landmark approach, but with less botulinum toxin required to achieve the clinical effect.

[Reality of inpatient vasoactive treatment with prostacyclin derivatives in patients with acral circulation disorders due to systemic sclerosis in Germany]. / Versorgungsrealität der stationären vasoaktiven Therapie mit Prostazyklinderivaten bei Patienten mit akralen Durchblutungsstörungen bei systemischer Sklerose in Deutschland.

BACKGROUND: Raynaud's phenomenon and the frequently ensuing digital ulcerations represent an early and very distressing symptom in patients with systemic sclerosis (scleroderma, SSc) causing significant limitations in the ability to work and quality of life. The use of vasoactive drugs (especially intravenous prostacyclin derivatives) is recommended to reduce the risk of hypoxic tissue damage up to the loss of fingers. METHODS: In order to obtain information about the current state of treatment of patients with prostacyclin derivatives in routine clinical life in Germany, a survey was conducted among the centers affiliated to the German Network for Systemic Scleroderma (DNSS). In addition, a separate patient survey was conducted by the schleroderma self-help group (Sklerodermie Selbsthilfe e. V.), which only covered the symptoms Raynaud's syndrome, digital ulcers and the use of intravenous prostacyclin derivatives. RESULTS: Of the 433 patients surveyed 56% stated that they had already been treated with prostacyclin derivatives (iloprost/alprostadil) because of their illness and symptoms. A total of 61% received the treatment for severe Raynaud's phenomenon and 39% for digital ulcerations. Most respondents not only experienced an improvement in Raynaud's phenomenon and digital ulcers but also a significant improvement of limitations in everyday life. They also needed significantly less outside help and absenteeism from work was much lower. CONCLUSION: Patients consistently reported a positive effect of treatment with prostacyclin derivatives on Raynaud's phenomenon, acral ulcerations, pain and daily restrictions and felt well and safely cared for during inpatient treatment. These positive effects in the patients' perceptions provide crucial information supporting and confirming the current European and international treatment recommendations.

Ulnar Artery Thrombosis Presented with Unilateral Raynaud's Phenomenon Findings after Long-Term Intensive Handicraft Activity: Hypothenar Hammer Syndrome.

BACKGROUND: Hypothenar hammer syndrome (HHS) is an uncommon vascular syndrome of upper extremity. HHS should be considered in patients who are presented with digital ischemia. Distal ulnar artery compression at the level of Guyon's canal with trauma results in thrombus or aneurysm. It may be observed after repetitive chronic trauma or acute blunt trauma to hypothenar eminence. Middle-aged male laborers, smokers, and dominant hands are affected frequently. Hand pain, discoloration or ulceration of digits, cold intolerance, hypothenar pulsatile mass, hypothenar weakness, and numbness are significant clinical findings. CASE CHARACTERISTICS: In this report, we presented a 37-year-old woman complaining with intermittent hand pain, paleness, and cyanosis at third, fourth, and fifth fingers of the right hand. She had no blunt trauma to her hand but intense amount of needle lace with her hands. Doppler ultrasonography revealed ulnar arterial thrombus at right Guyon's canal level. CONCLUSIONS: She was diagnosed as HHS secondary to intense needlework. A calcium channel blocker and low-dose aspirin were prescribed to her, and avoidance of hand traumas was suggested. These interventions relieved digital ischemia symptoms on her hand.

The clinical effects of l-arginine and asymmetric dimethylarginine: implications for treatment in secondary Raynaud's phenomenon.

Secondary Raynaud's phenomenon (RP) is often the sentinel clinical finding in systemic sclerosis and may precede systemic disease by several years. Altered nitric oxide metabolism plays a critical role in both fibrosis and severe secondary RP phenotypes in these patients. Increased flux through inducible nitric oxide synthase (iNOS) drives cutaneous fibrosis. Failure of flux through endothelial nitric oxide synthase (eNOS) contributes to increased vasoconstriction and decreased vasorelaxation. The underproduction of nitric oxide by eNOS is in part due to increased levels of asymmetric dimethylarginine (ADMA), an endogenous competitive inhibitor of nitric oxide synthase. The inhibitory effects of increased ADMA levels may be counteracted increasing serum l-arginine, which is often an effective treatment strategy in these patients. As such, l-arginine-based therapies should be considered in managing secondary RP, particularly given their favourable safety and tolerability profile. While there is no established dosing regimen, studies of oral l-arginine in secondary RP suggest that divided dosing may begin at 1-2 g/day and may be titrated up to 10 g/day. Conversely, primary RP is not associated with increased ADMA production which likely accounts for the failure of l-arginine trials to show benefit in primary RP.

Botulinum Toxin in the Long-Term Treatment of Refractory Raynaud's Phenomenon

Raynaud's phenomenon is an exaggerated physiological response of blood vessels in the distal extremities to emotional stress and cold. It can be idiopathic or secondary to a connective tissue disorder, such as scleroderma or systemic lupus erythematosus. Treatment for Raynaud's phenomenon consists primarily of lifestyle modifications; if unsuccessful, pharmacotherapy with dihydropyridine calcium channel blockers can be added. Botulinum toxin (BTX-A) is a neurotoxic protein produced by Clostridium botulinum spores. While most widely known for its cosmetic use, BTX-A has many therapeutic utilities due to its ability to inhibit multiple neurotransmitters. In this report, we present a patient with Raynaud's phenomenon refractory to standard therapies whose symptoms resolved after treatment with BTX-A. Follow-up with the patient after one and five years showed no relapse or recurrence of symptoms. J Drugs Dermatol. 2019;18(9):943-945.

On-Demand Sildenafil as a Treatment for Raynaud Phenomenon: A Series of n-of-1 Trials.

Background: Treatment of Raynaud phenomenon (RP) with phosphodiesterase-5 inhibitors has shown moderate efficacy. Adverse effects decrease the risk-benefit profile of these drugs, and patients may not be willing to receive long-term treatment. On-demand single doses before or during exposure to cold may be a good alternative. Objective: To assess the efficacy and safety of on-demand sildenafil in RP. Design: Series of randomized, double-blind, n-of-1 trials. (ClinicalTrials.gov: NCT02050360). Setting: Outpatients at a French university hospital. Participants: Patients with primary or secondary RP. Intervention: Each trial consisted of a multiple crossover study in a single patient. Repeated blocks of 3 periods of on-demand treatment were evaluated: 1 week of placebo, 1 week of sildenafil at 40 mg per dose, and 1 week of sildenafil at 80 mg per dose, with a maximum of 2 doses daily. Measurements: Raynaud Condition Score (RCS) and frequency and daily duration of attacks. Skin blood flow in response to cooling also was assessed with laser speckle contrast imaging. Mixed-effects models were used and parameters were estimated in a Bayesian framework to determine individual and aggregated efficacy. Results: 38 patients completed 2 to 5 treatment blocks. On the basis of aggregated data, the probability that sildenafil at 40 mg or 80 mg was more effective than placebo was greater than 90% for all outcomes (except for RCS with sildenafil, 80 mg). However, the aggregated effect size was not clinically relevant. Yet, substantial heterogeneity in sildenafil's efficacy was observed among participants, with clinically relevant efficacy in some patients. Limitation: The response to sildenafil was substantially heterogeneous among patients. Conclusion: Despite a high probability that sildenafil is superior to placebo, substantial heterogeneity was observed in patient response and aggregated results did not show that on-demand sildenafil has clinically relevant efficacy. In this context, the use of n-of-1 trials may be an original and relevant approach in RP. Primary Funding Source: GIRCI (Groupement Interrégional de Recherche Clinique et d'Innovation) Auvergne Rhône-Alpes (academic funding) and Pfizer.