Recent achievements in the management of Raynaud's phenomenon

Raynaud's Phenomenon: A Current Update on Pathogenesis, Diagnostic Workup, and Treatment

Raynaud's phenomenon (RP) is a condition characterized by episodic, excessive vasoconstriction in the fingers and toes, triggered by cold or stress. This leads to a distinctive sequence of color changes in the digits. Pallor indicates reduced blood flow due to oxygen deprivation, while erythema appears as reperfusion. RP can be primary, with no identifiable underlying cause, or secondary, associated with other conditions. These conditions include autoimmune diseases, most commonly systemic sclerosis, vascular diseases; and neurological conditions. While the exact cause of RP remains unclear, genetic and hormonal (estrogen) factors are likely contributors. The pathogenesis of RP involves a complex interaction between the vascular wall, nerves, hormones, and humoral factors, disrupting the balance between vasoconstriction and vasodilation. In primary RP, the vascular abnormalities are primarily functional. However, in secondary RP, both functional and structural components occur in blood vessels. This explains why digital tissue damage frequently occurs in secondary RP but not primary RP. Diagnosis of RP is primarily clinical. Recent advancements in imaging techniques have aided in diagnosis and monitoring, but nail fold capillaroscopy remains the gold standard for distinguishing between primary and secondary RP. If there are signs of acute ischemic injury, vascular imaging, particularly preoperatively, is crucial to rule out other vaso-occlusive conditions. Management of RP focuses on alleviating symptoms and preventing tissue damage. Vasodilator medications are the first-line treatment when general measures like warmth and stress management are not sufficient. Dihydropyridine calcium channel blockers (CCBs), such as nifedipine, are commonly used for vasodilation. Phosphodiesterase-5 inhibitors and prostaglandin analogs are alternative options for patients who do not respond to CCBs or have ischemic tissue damage. Bosentan, an endothelin-1 receptor antagonist, has shown effectiveness in treating and preventing digital ulcers, especially in patients with multiple ulcers. For severe cases, botulinum toxin injections or sympathectomy surgery can be used to control RP symptoms. However, botulinum toxin injections require repeated administration, and sympathectomy's long-term effectiveness is uncertain. Fat grafting is a promising surgical therapy for promoting healing and preventing tissue injury.

Identification of novel signal of Raynaud's phenomenon with Calcitonin Gene-Related Peptide(CGRP) antagonists using data mining algorithms and network pharmacological approaches

BACKGROUND

Calcitonin gene-related peptide (CGRP) antagonists are recently approved for the treatment of migraine.

AIM

The main aim of the current study was to find out the association of CGRP antagonists with RP using data mining algorithms integrated with network pharmacological approaches.

RESEARCH DESIGN AND METHODS

The individual case safety reports were extracted using OpenVigil2.1-MedDRA-V17 (2004Q1-2022Q3), the United States Adverse Event Reporting System (US FAERS). The data mining algorithms i.e. reporting odds ratio (ROR) with 95% confidence and proportionality reporting ratio (PRR) with associated chi-square value were calculated along with a minimum of three ICSRs to identify the signal. Further, the network was constructed using Cytoscape 3.7.2. Finally, molecular docking was performed using Glide, Schrodinger Inc.

RESULTS

The PRR ≥2 with a linked chi-square value ≥4, add up of co-occurrence ≥3, and a lower limit of 95% confidence interval of ROR exceeding 2 indicates a positive signal of RP. Further, the network pharmacological and molecular docking results have shown the involvement of insulin-like growth factor 1-receptor (IGF1R) pathways.

CONCLUSION

The RP is recognized as a novel signal with all CGRP antagonists.

Raynaud's Phenomenon: Reviewing the Pathophysiology and Management Strategies

Raynaud's phenomenon (RP) is a multifactorial vasospastic disorder characterized by a transient, recurrent, and reversible constriction of peripheral blood vessels. RP is documented to affect up to 5% of the general population, but variation in its prevalence is commonly recognized owing to many factors, including varied definitions, gender, genetics, hormones, and region. Furthermore, RP may be idiopathic or be a clinical manifestation of an underlying illness. Patients with RP classically describe a triphasic discoloration of the affected area, beginning with pallor, followed by cyanosis, and finally ending with erythema. This change in color spares the thumb and is often associated with pain. Each attack may persist from several minutes to hours. Moreover, the transient cessation of blood flow in RP is postulated to be mediated by neural and vascular mechanisms. Both structural and functional alterations observed in the blood vessels contribute to the vascular abnormalities documented in RP. However, functional impairment serves as a primary contributor to the pathophysiology of primary Raynaud's. Substances like endothelin-1, angiotensin, and angiopoietin-2 play a significant role in the vessel-mediated pathophysiology of RP. The role of nitric oxide in the development of this phenomenon is still complex. Neural abnormalities resulting in RP are recognized as either being concerned with central mechanisms or peripheral mechanisms. CNS involvement in RP may be suggested by the fact that emotional distress and low temperature serve as major triggers for an attack, but recent observations have highlighted the importance of locally produced factors in this regard as well. Impaired vasodilation, increased vasoconstriction, and several intravascular abnormalities have been documented as potential contributors to the development of this disorder. RP has also been observed to occur as a side effect of various drugs. Recent advances in understanding the mechanism of RP have yielded better pharmacological therapies. However, general lifestyle modifications along with other nonpharmacological interventions remain first-line in the management of these patients. Calcium channel blockers, alpha-1 adrenoreceptor antagonists, angiotensin-converting enzyme inhibitors, nitric oxide, prostaglandin analogs, and phosphodiesterase inhibitors are some of the common classes of drugs that have been found to be therapeutically significant in the management of RP. Additionally, anxiety management, measures to avoid colder temperatures, and smoking cessation, along with other simple modifications, have proven to be effective non-drug strategies in patients experiencing milder symptoms.

Алгоритмы лечения системной склеродермии при преимущественном поражении кожи и суставов, при синдроме Рейно и дигитальных язвах согласно современным рекомендациям

Системная склеродермия (ССД) (системный склероз) является уникальным заболеванием среди ревматических болезней, поскольку представляет проблему менеджмента хронической мультисистемной аутоиммунной патологии с широко распространенной облитерирующей васкулопатией малых артерий, связанной с разной степенью фиброза тканей. В патологический процесс могут вовлекаться все органы, так или иначе связанные с соединительной тканью и имеющие кровеносные сосуды. Прогрессирующее течение ССД приводит к развитию необратимых фиброзных изменений, в результате которых происходит нарушение функции пораженных органов. Отличительной чертой ССД является клиническая неоднородность подгрупп больных, которые различаются в зависимости от степени тяжести заболевания, вовлечения тех или иных органов и систем и дальнейшего прогноза. Врач должен тщательно обследовать каждого пациента с ССД для определения конкретных проявлений и уровня активности заболевания для назначения соответствующего лечения. В настоящее время использование алгоритмов лечения является современной стратегией ведения пациентов, особенно после неудачного использования препаратов первой линии. При ранней активной диффузной склеродермии с преимущественным поражением кожи следует отдать предпочтение метотрексату (МТХ) в качестве препарата первой линии, а при его неэффективности или непереносимости препаратом второй линии является мофетила микофенолат (ММФ), при неэффективности последнего препаратом третьей линии является внутривенный циклофосфамид. Следует заметить, что при тяжелом поражении кожи препаратом первой линии является ММФ, а МТХ — вторым, при неэффективности ММФ. На сегодняшний день блокаторы кальциевых каналов (БКК), главным образом нифедипин, остаются препаратами первой линии для терапии синдрома Рейно при ССД. При неэффективности этих лекарственных средств следует добавить ингибиторы фосфодиэстеразы-5 (иФДЕ-5), следующим шагом терапии является назначение ингибиторов ангиотензинпревращающего фермента или блокаторов рецепторов ангиотензина. При неэффективности комбинированной терапии БКК и иФДЕ-5, при тяжелом течении синдрома Рейно следует использовать простаноиды. Препаратом первой линии для лечения артрита, как и для поражения кожи, является МТХ, при его неэффективности или высокой воспалительной активности следует добавить глюкокортикоиды и нестероидные противовоспалительные препараты. Гидроксихинолон является препаратом третьей линии, его добавляют к терапии при неэффективности вышеперечисленных агентов. Биологические агенты (ритуксимаб и тоцилизумаб) являются препаратами четвертой линии лечения артрита, ассоциированного с ССД.

Bilateral uniportal video-assisted thoracoscopic sympathectomy for managing secondary Raynaud's in CREST syndrome: A case report

INTRODUCTION

Secondary Raynaud's is a manifestation that can present in CREST syndrome as a variant of five different diseases: Calcinosis, Raynaud's phenomenon, Esophageal dysmotility, Sclerodactyly, and Telangiectasia. Secondary Raynaud's presents as a result of an imbalance between vasoconstriction and vasodilation potentially leading to tissue ischemia. The mainstay treatment is medical while surgery treatment preserved as a last resort.

PRESENTATION OF CASE

A 28-year-old female presented with secondary Raynaud's and was subsequently diagnosed with CREST syndrome. The patient failed to respond to medical treatment, and gangrene of the right fourth distal phalanx developed. Stellate ganglion block was successfully used as a bridge to surgery. Uniportal video-assisted thoracoscopic surgery (VATS) sympathectomy was performed via a 2-cm incision, the sympathetic ganglia were identified and transected by cauterization at the level of the 3rd, 4th, and 5th intercostal spaces extending for a distance of 5 cm to ensure that the nerve of Kuntz was transected. The postoperative outcome was satisfactory, and the condition of the patient improved in a few months.

DISCUSSION

Different management modalities have been used to relieve the symptoms of secondary Raynaud's. The treatment ranges from lifestyle modification, medical treatment, and lastly surgical intervention. Sympathectomy has been suggested for the management of refractive secondary Raynaud's owing to its considerable clinical response.

CONCLUSION

The use of uniportal VATS sympathectomy results in favorable cosmetic and clinical outcomes including reduced length of hospital stay and postoperative pain.

Evaluation of topical econazole nitrate formulations with potential for treating Raynaud's phenomenon

The purpose of this work was to design and characterize a topical formulation of econazole nitrate (EN) with potential for treating Raynaud's phenomenon (RP). Four topical dosage forms (F1_topical solution, F2_HPMC or hydroxypropyl methylcellulose dispersion, F3_VersaBase^® cream, and F4_{_}Lipoderm^® Activemax™ Cream) containing 3% w/w EN were prepared and characterized for drug content, pH, viscosity, spreadability, drug crystallinity, stability, and in vitro permeation using Franz cells across pig ear skin, and results were compared to the 1% marketed EN cream. All four formulations had acceptable physical and visual characteristics required for topical application, with 3% w/w EN. The order of amount of drug permeated from highest to lowest was F2 (10.27%) > F4 (2.47%) > F1 (2.28%) > F3 (1.47%) > marketed formulation (0.22%). Formulation F2 showed better penetration of the drug into the stratum corneum, epidermis, and dermis layers. The drug concentration in the stratum corneum and epidermis was approximately 10-20 times higher with F2 compared to the marketed formulation. All formulations were found to be stable for up to 6 months. All four EN formulations were found to be better than the 1% marketed cream. Formulation F2_{_}HPMC dispersion could be further explored as a treatment option for RP.

Riociguat for the Treatment of Raynaud's Phenomenon: A Single-Dose, Double-Blind, Randomized, Placebo-Controlled Cross-Over Pilot Study (DIGIT)

BACKGROUND AND OBJECTIVE

Raynaud's phenomenon (RP) is characterized by transient digital ischemia and is commonly associated with connective tissue disease. Treatment remains unsatisfactory. Here we evaluate the efficacy, safety, and pharmacokinetics of a single dose of the soluble guanylate cyclase stimulator riociguat in RP.

METHODS

DIGIT was a double-blind, randomized, placebo-controlled pilot study. Patients with primary or secondary RP were randomized to a single oral dose of riociguat 2 mg or placebo in a cross-over design (7 ± 3 days). Efficacy was assessed as placebo-corrected change in digital blood flow 2 h post-dose at room temperature (RT) or following cold exposure (CE), measured by laser-speckle contrast analysis. Patients were regarded as responders if placebo-corrected digital blood flow increased by ≥ 10% from baseline at RT or after CE.

RESULTS

Of 20 eligible patients, 17 (85%) were female and mean [standard deviation (SD)] age was 52 (13.8) years. Placebo-corrected changes in digital blood flow were + 46% [90% confidence interval (CI) - 6 to + 98] at RT and - 9% (90% CI - 63 to + 44) after CE, with high inter-individual variability. Eight patients (40%) were responders at RT, and 12 (60%) after CE. Riociguat increased mean (SD) digital blood flow in responders at RT by + 136% (114) and in responders following CE by + 39% (53). Riociguat was well tolerated, with few adverse events.

CONCLUSION

In this pilot study, single-dose riociguat was well tolerated in patients with RP and resulted in improved digital blood flow in some patient subsets, with high inter-individual variability. Long-term evaluation is warranted.

Evaluation of cebranopadol, a dually acting nociceptin/orphanin FQ and opioid receptor agonist in mouse models of acute, tonic, and chemotherapy-induced neuropathic pain

BACKGROUND

Cebranopadol (a.k.a. GRT-6005) is a dually acting nociceptin/orphanin FQ and opioid receptor agonist that has been recently developed in Phase 2 clinical trials for painful diabetic neuropathy or cancer pain. It also showed analgesic properties in various rat models of pain and had a better safety profile as compared to equi-analgesic doses of morphine. Since antinociceptive properties of cebranopadol have been studied mainly in rat models, in the present study, we assessed analgesic activity of subcutaneous cebranopadol (10 mg/kg) in various mouse pain models.

METHODS

We used models of acute, tonic, and chronic pain induced by thermal and chemical stimuli, with a particular emphasis on pharmacoresistant chronic neuropathic pain evoked by oxaliplatin in which cebranopadol was used alone or in combination with simvastatin.

KEY RESULTS

As shown in the hot plate test, the analgesic activity of cebranopadol developed more slowly as compared to morphine (90-120 min vs. 60 min). Cebranopadol displayed a significant antinociceptive activity in acute pain models, i.e., the hot plate, writhing, and capsaicin tests. It attenuated nocifensive responses in both phases of the formalin test and reduced cold allodynia in oxaliplatin-induced neuropathic pain model. Its efficacy was similar to that of morphine. Used in combination and administered simultaneously, 4 or 6 h after simvastatin, cebranopadol did not potentiate antiallodynic activity of this cholesterol-lowering drug. Cebranopadol did not induce any motor deficits in the rotarod test.

CONCLUSION

Cebranopadol may have significant potential for the treatment of various pain types, including inflammatory and chemotherapy-induced neuropathic pain.

Unexpected drug-induced Raynaud phenomenon: Analysis from the French national pharmacovigilance database

OBJECTIVE

To estimate the association between exposure to medicinal products and Raynaud phenomenon.

METHODS

The study used the data of all adverse drug reactions notified to the French national pharmacovigilance database. All cases reported between 1st January 1995 and 10th December 2012 were selected. A case/non-case method was used to measure disproportionality of the association between drug exposure and Raynaud phenomenon. The cases concerned all observations involving Raynaud phenomenon. Non-cases comprised all other reports of adverse drug reactions over the same period.

RESULTS/DISCUSSION

Among the 307,128 adverse drug reaction reports selected from the French national pharmacovigilance database, 175 involved Raynaud phenomenon, most of them affecting women (61.1%). The mean age was 50.1 years, and 8% had a past medical history of Raynaud phenomenon. According to the summaries of product characteristics, 42.3% of these cases were exposed to drugs known to induce Raynaud phenomenon. Unexpected Raynaud phenomenons (unlisted in the summaries of product characteristics) were associated with exposure to drugs for which Raynaud phenomenons are published (interferons, ribavirin, gemcitabine) or for which Raynaud phenomenons are not published (hepatitis B vaccine, isotretinoin, leflunomide, hydroxycarbamide, rofecoxib, telmisartan, zolmitriptan).

CONCLUSION

The case/non-case method is usually used to generate signals. Further epidemiological studies are now necessary to confirm these findings.

Difficulties in diagnosis and treatment of severe secondary Raynaud's phenomenon in a Cameroonian woman: a case report

Background

Raynaud’s phenomenon is a microvascular disorder that results in exaggerated vasoconstriction over vasodilatation secondary to an alteration in autonomic control. Though benign, it can result in severe ulceration and ultimately gangrene associated with disfiguration and permanent deformity. We present a case of severe secondary Raynaud’s phenomenon in a black-African patient from a resource-limited setting, with focus on the difficulties encountered in the diagnosis and treatment.

Case presentation

A 43-year-old female Cameroonian farmer with a 7-year history of episodic paresthesia in her fingers and toes (when exposed to cold) presented to our emergency department with severe pain, ulceration, and “darkening” of her fingertips over a period of 2 days. An examination revealed bilateral ulceration and dry gangrene of her fingers and toes, based on which a diagnosis of secondary Raynaud’s phenomenon due to a connective tissue disease was proposed. Results of paraclinical investigations were normal. Lifestyle modification along with a calcium channel blocker and phosphodiesterase type 5 inhibitor provided significant relief.

Conclusions

An early diagnosis and knowledge on appropriate treatment of Raynaud’s phenomenon is of vital importance to prevent permanent tissue damage and disability. Relying on biphasic color change for the diagnosis of Raynaud’s phenomenon in black Africans can be potentially misleading.

Efficacy of cilostazol for the treatment of Raynaud's phenomenon in systemic sclerosis patients

Cilostazol is a selective inhibitor of phosphodiesterase-III with antiplatelet, antithrombotic and vasodilating properties. The aim of our study was to evaluate the effect of the drug on vasculopathy and Raynaud's phenomenon (RP), in a series of patients with systemic sclerosis (SSc), before and after cilostazol treatment. Twenty-one consecutive SSc patients with moderate or severe RP were enrolled in an open-label study. Cilostazol was administered at the dose of 100 mg twice a day, for 12 months. Evaluations included: daily RP attack diary documenting the frequency and duration of RP episodes, Health Assessment Questionnaire-Disability Index, scleroderma visual analogue scales (VAS), flow-mediated dilation and immunological status, including endothelin 1 and interleukin 6 plasma levels. Thirteen patients completed the study. RP duration and daily number episodes recorded over a 3-week period significantly decreased after cilostazol treatment (p = 0.0049 and p = 0.0067, respectively). VAS score indicated a significant amelioration of the patients' perception of RP (p = 0.0117), and both baseline and post-ischemic brachial artery diameters were significantly increased after cilostazol treatment, as compared with basal values (p = 0.0119 and p = 0.0076, respectively). None of the patients developed digital ulcers during the study. A significant clinical improvement of RP was recorded in SSc patients undergoing cilostazol treatment. Study results indicate a potential role of cilostazol as oral maintenance therapy in SSc patients with RP.

[Nailfold capillaroscopy]

Capillaroscopy is performed to evaluate the morphology, frequency and blood flow of nailfold capillaries as well as relevant extracapillary changes in rheumatic conditions. The main indication is the differentiation between primary and secondary Raynaud's phenomenon. Various rheumatic conditions show different and partially typical pathognomonic alterations of the microcirculation or capillary patterns. This simple, noninvasive, inexpensive and effective technique is well suited for early diagnosis, especially of connective tissue diseases. The specific significance is highest for systemic sclerosis which is the most frequently evaluated entity. The corresponding microscopic alterations allow stage-adapted conclusions concerning the acuity of inflammation to be formed. That is not the only reason why capillaroscopy represents an important tool in follow-up controls and together with other techniques, such as flow measurement by laser Doppler, further conclusions can be drawn.

The rs3768777-G allele of ITGAV gene is associated with rheumatoid arthritis

Integrin αvβ3 (vitronectin receptor) plays a prominent role in angiogenesis, a key pathogenic feature of rheumatoid arthritis (RA). Moreover, integrin αV (ITGAV) subunit gene has been associated with a susceptibility to RA. The aim of the present study was to detect the potential association between ITGAV gene polymorphisms and a susceptibility to RA in a Turkish cohort. DNA samples were harvested from 160 patients with RA and 144 healthy controls (HC). Three single-nucleotide polymorphisms of ITGAV gene (rs3738919, rs3768777, and rs10174098) were genotyped using real-time PCR. Serum vitronectin levels were analyzed in 30 RA patients, 28 Behçet's disease (BD) patients, and 30 HC subjects. There was no significant difference between the RA and HC groups in terms of the genotypic and allelic distributions of rs3738919 and rs10174098 polymorphisms. However, the prevalence of rs3768777-G allele was higher in the RA group than in the HC group (OR 2.3, 95 % CI 1.6-3.2, p < 0.0001). Moreover, there was a significant association between RA and the genotypic distribution of rs3768777 (GG + AG vs. AA: OR 2.1, 95 % CI 1.3-3.4; GG vs. AG + AA: OR 4.1, 95 % CI 2.1-7.8). Serum vitronectin levels were lower in the RA and BD groups than in the HC group (p ANOVA = 0.002). The rs3738919 and rs10174098 polymorphisms of the ITGAV gene seem not to be associated with susceptibility to RA in Turkish patients. However, rs3768777 increases the risk of RA in this group. These results suggest that the ITGAV gene may be a candidate gene for the etiopathogenesis of RA.

Dynamic adaptation of the peripheral circulation to cold exposure

Humans residing or working in cold environments exhibit a stronger cold-induced vasodilation (CIVD) reaction in the peripheral microvasculature than those living in warm regions of the world, leading to a general assumption that thermal responses to local cold exposure can be systematically improved by natural acclimatization or specific acclimation. However, it remains unclear whether this improved tolerance is actually due to systematic acclimatization, or alternately due to the genetic pre-disposition or self-selection for such occupations. Longitudinal studies of repeated extremity exposure to cold demonstrate only ambiguous adaptive responses. In field studies, general cold acclimation may lead to increased sympathetic activity that results in reduced finger blood flow. Laboratory studies offer more control over confounding parameters, but in most studies, no consistent changes in peripheral blood flow occur even after repeated exposure for several weeks. Most studies are performed on a limited amount of subjects only, and the variability of the CIVD response demands more subjects to obtain significant results. This review systematically surveys the trainability of CIVD, concluding that repeated local cold exposure does not alter circulatory dynamics in the peripheries, and that humans remain at risk of cold injuries even after extended stays in cold environments.

Segmental analysis of indocyanine green pharmacokinetics for the reliable diagnosis of functional vascular insufficiency

Accurate and reliable diagnosis of functional insufficiency of peripheral vasculature is essential since Raynaud phenomenon (RP), most common form of peripheral vascular insufficiency, is commonly associated with systemic vascular disorders. We have previously demonstrated that dynamic imaging of near-infrared fluorophore indocyanine green (ICG) can be a noninvasive and sensitive tool to measure tissue perfusion. In the present study, we demonstrated that combined analysis of multiple parameters, especially onset time and modified T(max) which means the time from onset of ICG fluorescence to T(max), can be used as a reliable diagnostic tool for RP. To validate the method, we performed the conventional thermographic analysis combined with cold challenge and rewarming along with ICG dynamic imaging and segmental analysis. A case-control analysis demonstrated that segmental pattern of ICG dynamics in both hands was significantly different between normal and RP case, suggesting the possibility of clinical application of this novel method for the convenient and reliable diagnosis of RP.