A vascular mechanistic approach to understanding Raynaud phenomenon. Nat Rev Rheumatol. 2015;11:146-158. [PMID: 25536485 DOI: 10.1038/nrrheum.2014.195]

Blood biomarkers for occupational hand-arm vibration exposure

Hand-arm vibration is a common occupational exposure that causes neurological impairment, myalgia, and vibration-induced Raynaud's phenomena or vibration white fingers (VWF). The pathological mechanism is largely unknown, though several mechanisms have been proposed, involving both immunological vascular damage and defective neural responses. The aim of this study was to test whether the substances interleukin-33 (IL-33), macrophage-derived chemokine (MDC), interleukin-10 (IL-10), endothelin-1 (ET-1), C-C motif chemokine ligand 20 (CCL20), calcitonin, and thromboxane (TXA2) changed before and after occupational hand-arm vibration exposure. 38 full-time shift workers exposed to hand-arm vibration were recruited. All the participants underwent medical examinations regarding symptoms of Raynaud's phenomena. In 29 of the participants, the concentration of IL-33, MDC, IL-10, ET-1, CCL20, calcitonin, and TXA2 was measured before and after a workday. There was a significant increase in ET-1 and calcitonin concentration and a decrease in the CCL20 concentration after the work shift in all participants. In the group suffering from VWF, but not in the non-VWF group, MDC was statistically significantly lower before the work shift (p = .023). The VWF group also showed a significant increase in MDC after the work shift. Exposure to occupational hand-arm vibration is associated with changes in ET-1, calcitonin, and MDC concentration in subjects suffering from vibration white fingers, suggesting a role of these biomarkers in the pathophysiology of this condition.

A case of misdiagnosed arterial thoracic outlet syndrome as primary Raynaud's phenomenon

Arterial thoracic outlet syndrome (aTOS) is a rare, but potentially, limb-threatening condition that is often misdiagnosed. We present the case of a 29-year-old man who was initially managed under the presumption of primary Raynaud's phenomenon for >1 year before the correct diagnosis of aTOS, and the delay in diagnosis was complicated by substantial distal thromboembolic occlusion. Successful staged treatment included thoracic outlet decompression, subclavian artery aneurysm repair with subclavian-to-axillary bypass, anticoagulation, and an unconventional axillary-to-ulnar artery bypass. This report highlights the diagnostic challenges of aTOS and the importance of considering it in patients with Raynaud's phenomenon and vaso-occlusive symptoms.

Temperature-responsive hydrogel-grafted vessel-on-a-chip: Exploring cold-induced endothelial injury

Cold-induced vasoconstriction is a significant contributor that leads to chilblains and hypothermia in humans. However, current animal models have limitations in replicating cold-induced acral injury due to their low sensitivity to cold. Moreover, existing in vitro vascular chips composed of endothelial cells and perfusion systems lack temperature responsiveness, failing to simulate the vasoconstriction observed under cold stress. This study presents a novel approach where a microfluidic bioreactor of vessel-on-a-chip was developed by grafting the inner microchannel surface of polydimethylsiloxane with a thermosensitive hydrogel skin composed of N-isopropyl acrylamide and gelatin methacrylamide. With a lower critical solution temperature set at 30°C, the gel layer exhibited swelling at low temperatures, reducing the flow rate inside the channel by 10% when the temperature dropped from 37°C to 4°C. This well mimicked the blood stasis observed in capillary vessels in vivo. The vessel-on-a-chip was further constructed by culturing endothelial cells on the surface of the thermosensitive hydrogel layer, and a perfused medium was introduced to the cells to provide a physiological shear stress. Notably, cold stimulation of the vessel-on-a-chip led to cell necrosis, mitochondrial membrane potential (ΔΨm) collapse, cytoskeleton disaggregation, and increased levels of reactive oxygen species. In contrast, the static culture of endothelial cells showed limited response to cold exposure. By faithfully replicating cold-induced endothelial injury, this groundbreaking thermosensitive vessel-on-a-chip technology offers promising advancements in the study of cold-induced cardiovascular diseases, including pathogenesis and therapeutic drug screening.

Painful Raynaud's mimics

Raynaud's syndrome is a common finding in many autoimmune conditions. Accurately diagnosing Raynaud's, and differentiating it from mimicking conditions, is imperative in rheumatologic diseases. Raynaud's syndrome and Raynaud's mimickers, especially painful Raynaud's mimickers, can prove a diagnostic challenge for the practicing rheumatologist. Painful Raynaud's mimickers can lead to increased patient stress and unnecessary medical work up; Healthcare providers need to be aware of Raynaud's mimickers when evaluating patient concerns of skin color changes and pain. The present narrative review aims to highlight Raynaud's syndrome, important painful mimickers that may be seen, diagnosis, and updated management recommendations.

Endothelial Dysfunction in Psoriasis: An Integrative Review

Vascular endothelial cells (ECs), the inner layer of blood vessels, were previously considered to be a passive lining that facilitates cellular and molecular exchange. However, recent studies have revealed that ECs can respond to various stimuli and actively regulate vascular function and skin inflammation. Specific subtypes of ECs are known to have significant roles in a diverse range of physiological and pathological processes in the skin. This review suggests that EC dysfunction is both causal and consequential in the pathogenesis of psoriasis. Further investigations into dysregulated pathways in EC dysfunction may provide new insights for the treatment of psoriasis.

Part II: The treatment of primary and secondary Raynaud's phenomenon

Raynaud phenomenon (RP) presents with either primary or secondary disease, and both have the potential to negatively impact patient quality of life. First-line management of RP should include lifestyle modifications in all patients. Some patients with primary RP and most with secondary RP require pharmacologic therapies, which may include calcium channel blockers, topical nitrates, phosphodiesterase 5 inhibitors, or endothelin antagonists. Additional approaches to treatment for those with signs of critical ischemia or those who fail pharmacologic therapy include botulinum toxin injection and digital sympathectomy. Herein, we describe in detail the treatment options for patients with RP as well as provide treatment algorithms for each RP subtype.

Part I: Epidemiology, pathophysiology, and clinical considerations of primary and secondary Raynaud's phenomenon

Raynaud's phenomenon (RP) is a relatively common disease with both primary and secondary forms. It is well understood as a vasospastic condition affecting the acral and digital arteries, resulting in characteristic, well-demarcated color changes typically in the hands and feet in response to cold or stress. Secondary RP (SRP) has been described in association with a variety of rheumatologic and nonrheumatologic diseases, environmental exposures, and/or medications. While both primary RP and SRP may impact the quality of life, SRP may lead to permanent and potentially devastating tissue destruction when undiagnosed and untreated. It is therefore crucial for dermatologists to distinguish between primary and secondary disease forms early in clinical evaluation, investigate potential underlying causes, and risk stratify SRP patients for the development of associated autoimmune connective tissue disease. The epidemiology, pathogenesis, and clinical presentation and diagnosis of both forms of RP are described in detail in this review article.

Inhibiting Intracellular α2C-Adrenoceptor Surface Translocation Using Decoy Peptides: Identification of an Essential Role of the C-Terminus in Receptor Trafficking

The G protein-coupled α2-adrenoceptor subtype C (abbreviated α2C-AR) has been implicated in peripheral vascular conditions and diseases such as cold feet-hands, Raynaud's phenomenon, and scleroderma, contributing to morbidity and mortality. Microvascular α2C-adrenoceptors are expressed in specialized smooth muscle cells and mediate constriction under physiological conditions and the occlusion of blood supply involving vasospastic episodes and tissue damage under pathological conditions. A crucial step for receptor biological activity is the cell surface trafficking of intracellular receptors, triggered by cAMP-Epac-Rap1A GTPase signaling, which involves protein-protein association with the actin-binding protein filamin-2, mediated by critical amino acid residues in the last 14 amino acids of the receptor carboxyl (C)-terminus. This study assessed the role of the C-terminus in Rap1A GTPase coupled receptor trafficking by domain-swapping studies using recombinant tagged receptors in transient co-transfections and compared with wild-type receptors using immunofluorescence microscopy. We further tested the biological relevance of the α2C-AR C-terminus, when introduced as competitor peptides, to selectively inhibit intracellular α2C-AR surface translocation in transfected as well as in microvascular smooth muscle cells expressing endogenous receptors. These studies contribute to establishing proof of principle to target intracellular α2C-adrenoceptors to reduce biological activity, which in clinical conditions can be a target for therapy.

Cooling-induced cutaneous vasodilatation is mediated by small-conductance, calcium-activated potassium channels in tail arteries from male mice

Cooling causes cutaneous dilatation to restrain cold-induced constriction and prevent tissue injury. Cooling increases communication through myoendothelial gap junctions (MEGJs), thereby increasing endothelium-derived hyperpolarization (EDH)-type dilatation. EDH is initiated by calcium-activated potassium channels (KCa ) activated by endothelial stimuli or muscle-derived mediators traversing MEGJs (myoendothelial feedback). The goal of this study was to determine the individual roles of KCa with small (SK3) and intermediate (IK1) conductance in cooling-induced dilatation. Vasomotor responses of mice isolated cutaneous tail arteries were analyzed by pressure myography at 37°C and 28°C. Cooling increased acetylcholine-induced EDH-type dilatation during inhibition of NO and prostacyclin production. IK1 inhibition did not affect dilatations to acetylcholine, whereas SK3 inhibition inhibited dilatation at both temperatures. Cooling uncovered myoendothelial feedback to inhibit constrictions in U46619. IK1 inhibition did not affect U46619 constrictions, whereas SK3 inhibition abolished the inhibitory effect of cooling without affecting U46619 constriction at 37°C. Immunoblots confirmed SK3 expression, which was localized (immunofluorescence) to holes in the internal elastic lamina consistent with myoendothelial projections. Immunoblots and Immunofluorescence did not detect IK1. Studies in non-cutaneous arteries have highlighted the predominant role of IK1 in EDH-type dilatation. Cutaneous arteries are distinctly reliant on SK3, which may enable EDH-type dilation to be amplified by cooling.

Efficacy analysis of minimally invasive surgery for Raynaud's syndrome

BACKGROUND

Raynaud's syndrome (RS), also referred to as Raynaud's phenomenon, is a vasospastic disorder causing episodic color changes in extremities upon exposure to cold or stress. These manifestations, either primary Raynaud's phenomenon (PRP) or associated with connective tissue diseases like systemic sclerosis (SSc) as secondary Raynaud's phenomenon (SRP), affect the quality of life. Current treatments range from calcium channel blockers to innovative surgical interventions, with evolving efficacy and safety profiles.

METHODS

In this retrospective study, patients diagnosed with RS were selected based on complete medical records, ensuring homogeneity between groups. Surgeries involved microscopic excision of sympathetic nerve fibers and stripping of the digital artery's adventitia. Postoperative care included antibiotics, analgesia, oral nifedipine, and heat therapies. Evaluation metrics such as the VAS pain score and RCS score were collected bi-weekly. Data analysis was conducted using SPSS 26.0, with significance set at p < 0.05.

RESULTS

In total, 15 patients formed the experimental group, with five presenting fingertip soft tissue necrosis and ten showing RS symptoms. Comparative analysis of demographic data between experimental and control groups, both containing 15 participants, demonstrated no significant age and gender difference. However, the "Mean Duration of RP attack" in the experimental group was notably shorter (9.47 min ± 0.31) than the control group (19.33 min ± 1.79). The RS Severity Score also indicated milder severity for the experimental cohort (score: 8.55) compared to the control (score: 11.23). Postoperative assessments at 2, 4, and 6 weeks revealed improved VAS pain scores, RCS scores, and other measures for the experimental group, showing significant differences (p < 0.05). One distinctive case showcased a variation in the common digital nerve and artery course in an RS patient.

CONCLUSION

Our retrospective analysis on RS patients indicates that microsurgical techniques are safe and effective in the short term. As surgical practices lean towards minimally invasive methods, our data supports this shift. However, extensive, prospective studies are essential for conclusive insights.

ADRA2A and IRX1 are putative risk genes for Raynaud's phenomenon

Raynaud's phenomenon (RP) is a common vasospastic disorder that causes severe pain and ulcers, but despite its high reported heritability, no causal genes have been robustly identified. We conducted a genome-wide association study including 5,147 RP cases and 439,294 controls, based on diagnoses from electronic health records, and identified three unreported genomic regions associated with the risk of RP (p < 5 × 10-8). We prioritized ADRA2A (rs7090046, odds ratio (OR) per allele: 1.26; 95%-CI: 1.20-1.31; p < 9.6 × 10-27) and IRX1 (rs12653958, OR: 1.17; 95%-CI: 1.12-1.22, p < 4.8 × 10-13) as candidate causal genes through integration of gene expression in disease relevant tissues. We further identified a likely causal detrimental effect of low fasting glucose levels on RP risk (rG = -0.21; p-value = 2.3 × 10-3), and systematically highlighted drug repurposing opportunities, like the antidepressant mirtazapine. Our results provide the first robust evidence for a strong genetic contribution to RP and highlight a so far underrated role of α2A-adrenoreceptor signalling, encoded at ADRA2A, as a possible mechanism for hypersensitivity to catecholamine-induced vasospasms.

Cold Finger: Raynaud Phenomenon Following Snakebite Envenoming by Nikolsky's Viper (Vipera berus nikolskii)

A field biologist was bitten by a female Nikolsky's viper (Vipera berus nikolskii) in Kharkiv Oblast, Ukraine. Two months later, the patient began to experience cold-induced vasospasm of the affected digit diagnosed as acquired Raynaud phenomenon. The patient had more than 30 occurrences during the single winter following the bite, but the signs and symptoms of Raynaud phenomenon disappeared with the end of winter. This report describes the case and puts it into context with the literature on the topic of toxin-induced peripheral vasospastic disorders and their potential importance in snakebite envenoming.

Cold Hands or Feet: Is It Raynaud's or Not?

Raynaud's phenomenon is an exaggerated response to cold stimuli that may be primary or secondary. The diagnosis relies on patient history and physical examination to distinguish RP from other vasomotor dysfunction (e.g. acrocyanosis, pernio, small fiber neuropathy with vasomotor symptoms, and complex regional pain syndrome). Achenbach syndrome, or spontaneous venous hemorrhage, may also be mistaken for RP but is a self-limiting phenomenon. Laboratory evaluation and vascular diagnostic testing may identify SRP causes. Regardless of etiology, treatment includes warming with trigger avoidance, and consideration of vasodilators (eg. calcium channel, alpha-1 blockers). SRP with digital ulceration may require PDE5i, endothelin-1 receptor blockers, and prostanoids. Refractory cases may require pneumatic arterial pumps, botulinum toxin administration, or surgical sympathectomy.

Solvent-Induced Raynaud's Phenomenon

Raynaud's phenomenon (RP) is a vasospastic disorder characterized by an exaggerated vasoconstrictive response to cold or emotional stress. It can be classified as primary (PRP) or secondary (SRP) depending on its association with an underlying condition. We present a case of a young female with severe RP, with trophic changes and abnormal capillaroscopy. After a detailed investigation, a diagnosis of secondary RP due to solvent exposure was made. The patient was treated with calcium channel blocker in low doses, due to hypotension, without improvement of symptoms. Vitamin C and pentoxifylline were added with an unsatisfactory response. Given the progressive worsening of RP and the appearance of trophic lesions, the patient's treatment was reviewed, and continuous intravenous iloprost infusion through an elastomeric pump was started. This resulted in significant symptom improvement and normalization on the capillaroscopic examination.

Vasoreactivity of the optic nerve head, nailfold, and facial skin in response to cold provocation in normal-tension glaucoma patients

BACKGROUND

The dysfunction of optic nerve head (ONH) hemodynamics has been suggested to be involved in the pathogenesis of normal-tension glaucoma (NTG). The aim of this study was to compare vasoreactivity in the ONH, nailfold, and facial skin in response to cold-water provocation in NTG patients and healthy controls.

METHODS

We performed cold-water provocation in 14 eyes of 14 NTG patients and 15 eyes of 15 age-matched control subjects. Laser speckle flowgraphy-derived tissue-area mean blur rate (MT), skin blood flowmetry-derived pulse wave amplitude (PA), nailfold capillaroscopy-derived nailfold capillary diameter, and other clinical parameters were recorded at baseline and 4 and 6 min after the cold stimulus. We compared changes (as percentages) in these variables in the NTG and control subjects with a linear mixed-effects model and evaluated correlations between these changes with Spearman's rank correlation coefficient.

RESULTS

The interaction term between the NTG group (reference, control group) and the 4-min protocol step (reference, baseline) significantly affected the changes in MT, nailfold capillary diameter and PA (β = -9.51%, P = 0.017, β = -20.32%, P = 0.002; β =  + 18.06%, P = 0.017, respectively). The change in MT was positively correlated with the change in nailfold capillary diameter, and negatively correlated with the change in PA (r = 0.39, P = 0.036; r = -0.40, P = 0.031, respectively).

CONCLUSION

NTG patients showed abnormal vasoconstriction in the ONH and nailfold and vasodilation in the facial skin in response to cold-water provocation.

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.

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.

Non-criteria antiphospholipid antibodies and pediatric rheumatic disease: a case series

BACKGROUND

Non-criteria antiphospholipid antibodies (NC-aPL) are a relatively undefined subgroup of antiphospholipid antibodies (aPL). Knowledge about NC-aPL in adults is limited and even less is known in pediatric patients. Routine tests for antiphospholipid syndrome (APS)-a clinical state marked by the presence of aPL in association with vascular thrombosis-usually include lupus anticoagulant (LAC), anti-cardiolipin (aCL) and -beta-2 glycoprotein I (aβ2GPI). LAC is a functional screen for prothrombotic aPL, while the latter tests identify specific autoantibodies. Specific targets of NC-aPL include, but are not limited to, phosphatidylethanolamine, phosphatidylserine, and prothrombin.

PRESENTATION OF CASES

We present single-center data from eight pediatric patients with NC-aPL identified during a three-year period. All patients had presenting features raising suspicion for APS. Most patients were female with a primary rheumatic disease. One patient had a stroke. Another patient had alveolar hemorrhage and pulmonary hypertension. Raynaud's phenomenon, rashes involving distal extremities, and headaches were common. Most patients had a positive LAC, yet their routine aPL tests were negative, prompting testing for NC-aPL.

CONCLUSIONS

Our findings suggest NC-aPL are associated with typical signs and symptoms of APS in pediatric patients. Pediatricians and pediatric subspecialists should consider NC-aPL when clinical suspicion is high and routine aPL tests are negative, particularly when LAC is positive. While guidelines for NC-aPL do not yet exist for children or adults, these autoantibodies have pathogenic potential. Actionable items could include evaluation for the presence of other (primary) rheumatic diseases, and consultation with hematologists and/or obstetricians regarding anticoagulation/platelet inhibition and thrombosis education. Future guidelines regarding NC-aPL will only be generated by gathering more data, ideally prospectively.

[Functional vascular acrosyndromes]

Vascular acrosyndromes are characterized by sparse, uniform clinical manifestations and a variety of possible pathomechanisms. The present article focuses on the functional entities. Raynaud phenomenon is based on cold- or stress-induced vasospasms of acral arteries. It is defined by the color changes of the skin, in the typical case white-blue-red (tricolore). The long fingers are most commonly affected. The etiology is unknown, and the pathophysiology is poorly understood. A distinction is made between primary and a secondary Raynaud phenomenon. The most important underlying diseases include collagenosis, primarily systemic sclerosis, and malignancies; furthermore, medications and drugs may promote vasospasm. Treatment is aimed at preventing or breaking the vasospasm, but has been only partially effective in doing so. Acrocyanosis is a vasospastic dystonic acral disorder that results in permanent reddish-livid discoloration, especially of the hands and feet. Secondary forms occur in collagenosis, malignancies, and myelodysplastic syndromes. The etiology and pathophysiology are virtually unknown. Targeted pharmacological intervention is not possible. Unlike all other vascular acrosyndromes, erythromelalgia is characterized by hyperemia. The primary form is a genetic sodium channelopathy, while secondary forms include malignancies, connective tissue diseases, and myelodysplastic syndromes. The symptoms are often distressing and disabling. Therapy requires a multimodal approach that includes both nonpharmacological and pharmacological strategies. Close interdisciplinary collaboration is essential for the management of this disease.

Raynaud's Phenomenon with Focus on Systemic Sclerosis

Raynaud’s phenomenon is a painful vascular condition in which abnormal vasoconstriction of the digital arteries causes blanching of the skin. The treatment approach can vary depending on the underlying cause of disease. Raynaud’s phenomenon can present as a primary symptom, in which there is no evidence of underlying disease, or secondary to a range of medical conditions or therapies. Systemic sclerosis is one of the most frequent causes of secondary Raynaud’s phenomenon; its appearance may occur long before other signs and symptoms. Timely, accurate identification of secondary Raynaud’s phenomenon may accelerate a final diagnosis and positively alter prognosis. Capillaroscopy is fundamental in the diagnosis and differentiation of primary and secondary Raynaud’s phenomenon. It is helpful in the very early stages of systemic sclerosis, along with its role in disease monitoring. An extensive range of pharmacotherapies with various routes of administration are available for Raynaud’s phenomenon but a standardized therapeutic plan is still lacking. This review provides insight into recent advances in the understanding of Raynaud’s phenomenon pathophysiology, diagnostic methods, and treatment approaches.

Prevalence of Raynaud's Phenomenon in Saudi Arabia

Purpose

Raynaud’s phenomenon (RP) is defined as frequent ischaemic attacks in the fingers and toes due to vascular vasospasm. Studies have been conducted in many countries worldwide to determine the prevalence of RP. The aim of the current study was to assess the prevalence of RP in the Saudi Arabian population.

Patients and Methods

An online survey based on international consensus criteria used to diagnose RP was conducted to collect data from individuals from the Saudi population. Participants were considered positive if they had triphasic or biphasic colours of the extremities with cold-related sensitivity. Awareness of RP was also assessed.

Results

A total of 1025 responses were collected and included in the final analysis. The prevalence of RP was 4.29%, including 22% men and 77% women. The most common age group among women was 26–40 years (36.3%). Familiarity with RP was low, with 56.82% of participants lacking adequate awareness regarding RP. Only 32% of patients with RP reported attending doctor visits regarding symptoms of the disease.

Conclusion

The RP prevalence in Saudi Arabia is comparable to that reported in the international literature. Public awareness activities should be conducted to increase knowledge about RP.

Trial Registration

Not applicable.

The Association of Flow-Mediated Dilatation and Blood Parameters in Primary Raynaud's Phenomenon

INTRODUCTION

Raynaud's phenomenon (RP) is a multifactorial disorder. If any underlying disease cannot be determined to be responsible for RP, then it is considered to be the primary RP (pRP). We aimed to investigate the differences between laboratory markers and impaired endothelial function in pRP.

MATERIALS AND METHODS

Forty-two pRP patients and 30 healthy individuals were included as the study and control groups, respectively. The endothelial function was evaluated with flow-mediated dilatation (FMD) of the brachial artery. The blood samples were obtained from both groups, and white blood cell (WBC), hemoglobin, platelets, mean platelet volume (MPV), creatinine, alanine aminotransferase (ALT), aspartate aminotransferase (AST), D-dimer, fibrinogen, albumin, fibrinogen-to-albumin ratio (FAR), neutrophil-to-lymphocyte ratio (NLR), D-dimer-to-albumin ratio (DDAR), and monocyte chemoattractant protein-1 (MCP-1) parameters were studied. The blood parameters and FMD values obtained were compared between groups.

RESULTS

The groups were similar in regard to age, gender, and smoking history (p < 0.05). There was no difference between the two groups in regard to hemoglobin, platelet, MPV, creatinine, ALT, D-dimer, albumin, FAR, NLR, and DDAR levels (p < 0.05). AST levels were slightly higher in the pRP group (p=0.027). Markedly increased WBC, fibrinogen, MPV, and MCP-1 values were detected in the pRP group (p=0.001), as well as higher abnormal FMD responses (p=0.001). There was a direct correlation between abnormal FMD response and serum MCP-1 values in patients with pRP (R: 0.308, R ²: 0.095, p: 0.044).

CONCLUSION

It seems to be that MCP-1 levels are higher in patients with pRP, and increased values of MCP-1 levels seem to be related to impaired endothelial functions.

Oral Glucose Load and Human Cutaneous Microcirculation: An Insight into Flowmotion Assessed by Wavelet Transform

Simple Summary

There is increasing evidence to suggest that microcirculation becomes dysfunctional earlier than large blood vessels or the heart in several diseases. In diabetes mellitus, a disease characterized by chronic hyperglycemia, microvascular impairment is well-established; on the contrary, the effect of acute hyperglycemia in microcirculation remains unclarified. Our aim was to investigate the microvascular effect of an oral glucose load (OGL) using laser Doppler flowmetry (LDF) as a perfusion quantification technique, coupled with wavelet transform (WT) to perform a spectral decomposition of the LDF signal. On two distinct occasions (pre-load and post-load), sixteen healthy subjects drank either a standard glucose solution or water. Perfusion was assessed by LDF and WT while resting and during post-occlusive reactive hyperemia (PORH), evoked by a transient three-min occlusion of the brachial artery, in the forearm and the finger pulp. The OGL affected microcirculation in both sites compared to water, significantly blunting the PORH response in the forearm. The WT revealed significant differences in the cardiac and sympathetic components after OGL between the pre-load and post-load periods. These results suggest that an OGL induces a short-term subtle microvascular impairment, probably involving a modulation of the sympathetic nervous system.

Abstract

Microcirculation in vivo has been assessed using non-invasive technologies such as laser Doppler flowmetry (LDF). In contrast to chronic hyperglycemia, known to induce microvascular dysfunction, the effects of short-term elevations in blood glucose on microcirculation are controversial. We aimed to assess the impact of an oral glucose load (OGL) on the cutaneous microcirculation of healthy subjects, quantified by LDF and coupled with wavelet transform (WT) as an interpretation tool. On two separate occasions, sixteen subjects drank either a glucose solution (75 g in 250 mL water) or water (equal volume). LDF signals were obtained in two anatomical sites (forearm and finger pulp) before and after each load (pre-load and post-load, respectively), in resting conditions and during post-occlusive reactive hyperemia (PORH). The WT allowed decomposition of the LDF signals into their spectral components (cardiac, respiratory, myogenic, sympathetic, endothelial NO-dependent). The OGL blunted the PORH response in the forearm, which was not observed with the water load. Significant differences were found for the cardiac and sympathetic components in the glucose and water groups between the pre-load and post-load periods. These results suggest that an OGL induces a short-term subtle microvascular impairment, probably involving a modulation of the sympathetic nervous system.

The Effect of Very Low Concentrations of Ethanol on Microvascular Artery and Vein Anastomosis: An Experimental Study

OBJECTIVES

This study investigated the effect of very low concentrations of ethanol on artery and vein anastomosis. Also, it was aimed to determine the appropriate ethanol concentration to be used in vasospasm.

METHODS

Rats were divided into five groups of eight rats, each group, as follows: Group i: saline; Group ii: 2.5% ethanol; Group iii: 5% ethanol; Group IV: 7.5% ethanol; and Group V: 10% ethanol. During the femoral artery and vein anastomosis, 1ml of the agent was used for irrigation in each group. Vessel diameters were measured before the anastomosis, at the fifth and 15th minutes, and the third week after the anastomosis. Histopathological samples were taken in the third week.

RESULTS

In Groups ii and iii, the mean vessel diameters were found to increase 15th minute. Also observed was an increase in mean vessel diameter that continued in the third week. Although acute vasodilation was detected in Groups IV and V, arterial and venous thrombosis was observed in the third week. Intima and media thickness decreased in Group ii, while it increased in Group iii. Perivascular inflammation and fibrosis increased as the ethanol concentration increased.

CONCLUSION

2.5% ethanol causes acute and prolonged vasodilation and does not cause endothelial cell damage, perivascular inflammation, and fibrosis. 2.5% ethanol will be a powerful alternative use in many situations that occur with vasospasm.

Occupational noise exposure and Raynaud's phenomenon: a nested case-control study

The primary aim of this study was to determine if self-reported occupational noise exposure was associated with Raynaud’s phenomenon. In northern Sweden, a nested case–control study was performed on subjects reporting Raynaud’s phenomenon (N=461), and controls (N=763) matched by age, sex and geographical location. The response rate to the exposure questionnaire was 79.2%. The study showed no statistically significant association between occupational noise exposure and reporting Raynaud’s phenomenon (OR 1.10; 95% CI 0.83–1.46) in simple analyses. However, there was a trend towards increasing OR for Raynaud’s phenomenon with increasing noise exposure, although not statistically significant. Also, there was a significant association between noise exposure and hearing loss (OR 2.76; 95% CI 2.00–3.81), and hearing loss was associated with reporting Raynaud’s phenomenon (OR 1.52; 95% CI 1.03–2.23) in a multiple regression model. In conclusion, self-reported occupational noise exposure was not statistically significantly associated with Raynaud’s phenomenon, but there was a dose–effect trend. In addition, the multiple model showed a robust association between hearing loss and Raynaud’s phenomenon. These findings offer some support for a common pathophysiological background for Raynaud’s phenomenon and hearing loss among noise-exposed workers, possibly through noise-induced vasoconstriction.

New mechanism-based approaches to treating and evaluating the vasculopathy of scleroderma

PURPOSE OF REVIEW

Utilizing recent insight into the vasculopathy of scleroderma (SSc), the review will highlight new opportunities for evaluating and treating the disease by promoting stabilization and protection of the microvasculature.

RECENT FINDINGS

Endothelial junctional signaling initiated by vascular endothelial-cadherin (VE-cadherin) and Tie2 receptors, which are fundamental to promoting vascular health and stability, are disrupted in SSc. This would be expected to not only diminish their protective activity, but also increase pathological processes that are normally restrained by these signaling mediators, resulting in pathological changes in vascular function and structure. Indeed, key features of SSc vasculopathy, from the earliest signs of edema and puffy fingers to pathological disruption of hemodynamics, nutritional blood flow, capillary structure and angiogenesis are all consistent with this altered endothelial signaling. It also likely contributes to further progression of the disease including tissue fibrosis, and organ and tissue injury.

SUMMARY

Restoring protective endothelial junctional signaling should combat the vasculopathy of SSc and prevent further deterioration in vascular and organ function. Indeed, this type of targeted approach has achieved remarkable results in preclinical models for other diseases. Furthermore, tracking this endothelial junctional signaling, for example by assessing vascular permeability, should facilitate insight into disease progression and its response to therapy.

Botulinum toxin in the management of primary and secondary Raynaud's phenomenon

Raynaud's phenomenon (RP) is common in rheumatic diseases. In the setting of systemic sclerosis (SSc), it can be complicated by digital ischemia that includes ulceration and gangrene. Systemic adverse effects may preclude the use of oral or topical vasodilators for the treatment of RP and its complications. In this article, we review effectiveness/efficacy of botulinum toxin injection in primary and secondary RP. We discuss botulinum toxin formulations, dosage, sites of administration, and adverse effects. The evidence for botulinum toxin in the treatment of primary and SSc-associated RP is promising. Consistency across patient populations, treatment options (botulinum serotype, dose, and injection site), and outcome measures will be essential for further research.

Cytokines Involved in the Pathogenesis of SSc and Problems in the Development of Anti-Cytokine Therapy

Systemic sclerosis (SSc) is a connective tissue disease of unknown etiology. SSc causes damage to the skin and various organs including the lungs, heart, and digestive tract, but the extent of the damage varies from patient to patient. The pathology of SSc includes ischemia, inflammation, and fibrosis, but the degree of progression varies from case to case. Many cytokines have been reported to be involved in the pathogenesis of SSc: interleukin-6 is associated with inflammation and transforming growth factor-β and interleukin-13 are associated with fibrosis. Therapeutic methods to control these cytokines have been proposed; however, which cytokines have a dominant role in SSc might differ depending on the extent of visceral lesions and the stage of disease progression. Therefore, it is necessary to consider the disease state of the patient to be targeted and the type of evaluation method when an anti-cytokine therapy is conducted. Here, we review the pathology of SSc and potential cytokine targets, especially interleukin-6, as well as the use of anti-cytokine therapy for SSc.

Richter J. Raynaud's Phenomenon: A Vascular Acrosyndrome That Requires Long-Term Care

BACKGROUND

Some 5-10% of the German population are affected by Raynaud's phenomenon (RP). In around 10-20% of cases RP arises from an underlying disease, most commonly a connective tissue disease. This review encompasses the diagnosis and differential diagnosis of RP and examines the efficacy of the currently available pharmaceutical and non-pharmaceutical treatment options.

METHODS

We conducted a selective literature search in PubMed using the search terms "Raynaud's phenomenon", "Raynaud's syndrome," "vasospasm," "vascular acrosyndrome," and "systemic sclerosis," together with a search of the Cochrane Database of Systematic Reviews up to April 2020.

RESULTS

Raynaud's phenomenon mainly affects the fingers or toes and is typically triggered by cold or emotional stressors. The most important diagnostic steps are demonstration of a tendency towards digital vasospasm, exclusion of occlusions in the afferent arteries and acral vessels, nail-fold capillaroscopy, and determination of autoantibody status. Tumor screening should be arranged in the presence of B symptoms or first manifestation of RP in old age. The onset of RP in childhood is a rare occurrence and points to a secondary origin. The principal options for treatment are protection against cold and administration of calcium antagonists, which reduces the occurrence of RP by around 20-40 %. The treatment of RP in patients with systemic sclerosis is described in the recommendations of the European League Against Rheumatism (EULAR).

CONCLUSION

At onset or after years of latency, patients with Raynaud phenomenon may have an underlying disease (most commonly a connective tissue disease). Long-term specialist care is necessary for asymptomatic patients with risk factors and for those with clinically manifest symptoms of an underlying condition alike.

Raynaud's phenomenon and related vasospastic disorders

Raynaud's phenomenon, which is characterized by episodic digital pallor, cyanosis and rubor upon exposure to cold environment or to stress, is relatively common, although the prevalence depends on the climate. Still, it is under-diagnosed, under-treated, and often confused with other conditions. Primary Raynaud's phenomenon (i.e., Raynaud disease) must be distinguished from secondary Raynaud's phenomenon (i.e., Raynaud syndrome) as long-term morbidity and outcomes differ vastly between the two conditions. Additionally, the practitioner must differentiate between Raynaud's phenomenon and related vascular disorders, such as acrocyanosis, pernio, and livedo reticularis. In this article, we review differences between the conditions and suggest an approach to diagnosis and treatment strategy for these disorders.

Metabolic Pattern of Systemic Sclerosis: Association of Changes in Plasma Concentrations of Amino Acid-Related Compounds With Disease Presentation

OBJECTIVE

Amino acids (AA) and their derivatives play an integral role in the synthesis of structural and regulatory elements in human organisms and therefore pathologies such as systemic sclerosis that may alter the blood pattern of these compounds. This study aimed to evaluate changes in plasma concentrations of amino acid-related metabolites in systemic sclerosis in a search for potential biomarkers and mechanisms of the disease.

METHODS

Plasma samples from 42 patients diagnosed with systemic sclerosis (SSc) according to the 2013 American College of Rheumatology and European League Against Rheumatism ACR/EULAR classification criteria were compared to 27 matched healthy controls. Liquid chromatography/mass spectrometry was applied for the analysis of 36 amino acid-related metabolites.

RESULTS

The analysis of plasma AA metabolite patterns revealed the number of changes including an increase (20%) in concentrations of NO synthase (NOS) inhibitor asymmetric dimethylarginine (ADMA) in SSc vs. healthy subjects. Furthermore, SSc patients had higher glutamine, proline, betaine, 1-methylhistidine, and methylnicotinamide levels, while the concentration of tryptophan was lower. The specific metabolic pattern was identified for several aspects of disease presentation. Most interestingly NOS inhibitor L-NAME was elevated in patients with diffuse systemic sclerosis or telangiectasia.

CONCLUSIONS

These results provide further evidence for the involvement of endothelium-dependent pathways in the mechanisms and presentation of SSc. Endothelial dysfunction biomarkers may be useful in the assessment of presentation and prognosis in SSc.

Public interest in Raynaud's phenomenon: A Google Trends analysis

Raynaud's phenomenon is a common disorder affecting body extremities and other vascular beds. As infodemiological methods have developed, online search tools could be used to explore the public interest of the disease. The study aimed to determine the annual trend, seasonal pattern, and associated topics of Raynaud's phenomenon. Google Trends was used to collect the data. "Raynaud syndrome" was selected as the search term. Data on monthly relative search volume (RSV) were collected from four selected countries (United States, United Kingdom, Australia, and New Zealand) and globally. Related topics were obtained, and annual-related topics were also collected for analysis. The maximum RSV appeared in January 2019, and the minimum value was observed in August 2011. The peak for RSV occurred in winter, and the bottom appeared in summer. In top related topics, "Maurice Raynaud" was the most related. In rising related topics, disease manifestations and autoimmune connective diseases were highly concerned. For annual-related topics, associated diseases were attracting more attention over time. The population is interested in related diseases, pathogenesis, and treatment. There was a peak in winter for searching and supported the importance of season variation on the impact of Raynaud's phenomenon.

Impact of global warming on Raynaud's phenomenon: a modelling study

Background: Raynaud's phenomenon is induced by excessive vasoconstriction of the peripheral microcirculation in response to environmental factors, essentially cold, but also stress or emotions. The objective of the present study is to evaluate the impact of global warming on the worldwide prevalence and severity of Raynaud's phenomenon over the 21 st century. Method: We first estimated the correlation between average temperature and prevalence and severity of Raynaud's phenomenon. Then, we mapped the prevalence and the severity of Raynaud's phenomenon worldwide at Christmas 1999 using historical data and, using climate projections from the Inter-Sectoral Impact Model Intercomparison Project, we predicted the prevalence and severity of Raynaud's phenomenon at Christmas 2099 according to four greenhouse-gas emission scenarios. Results: The prevalence of Raynaud's phenomenon in the general population is expected to decrease by 0.5% per degree Celsius increase. Furthermore, patients are expected to suffer from one less attack per week for each increase of 2.5 degrees Celsius.  Conclusions: Our study shows that global warming may have a significant impact on the prevalence and the severity of Raynaud's phenomenon over the 21 st century. However, as expected, this will greatly depend on the level of greenhouse-gas emissions.

Is Botulinum Toxin Useful in Systemic Sclerosis Related Peripheral Vasculopathy? A Literature Review

INTRODUCTION

In systemic sclerosis (SSc), peripheral vasculopathy presents typically as Raynaud Phenomenon (RP) and Digital Ulceration (DU). Over the last decade, botulinum toxin (BT) has been reported effective in this scenario. Our goal was to review existing literature evaluating the efficacy of BT on RP/DU in SSc.

MATERIALS AND METHODS

We performed a search in Pubmed with the MeSH terms "systemic sclerosis" and "botulinum toxin". Original studies evaluating BT in the treatment of SSc-associated RP/DU were considered for inclusion. Results were screened by title, abstract and full-text.

RESULTS

We identified 30 results, of which 5 original papers were included: 2 randomized controlled trials (RCT), 2 case series and 1 case control study, from a total of 133 patients. Only one RCT showed negative results, with worse blood flow in treated arm, but with lower dose of BT. Despite this, all 5 included studies reported improvement of at least 1 RP/hand function outcome measure. Concerning DU healing, resolution of baseline DU at the end of follow-up was reported in 75-100% of the patients, with 1 RCT showing superiority over placebo. The only reported adverse effect was transient hand weakness, affecting only 0-16.7% of patients. BT injection protocols were highly heterogeneous.

CONCLUSION

Despite conflicting results in 1 RCT, evidence points BT as an option in the treatment of SSc-related peripheral vasculopathy. However, future larger prospective trials are necessary to corroborate this hypothesis.

The Role of Endogenous Eicosapentaenoic Acid and Docosahexaenoic Acid-Derived Resolvins in Systemic Sclerosis

Resolvins, the member of specialized pro-resolving mediators, are produced from omega-3 polyunsaturated fatty acids as a response to an acute inflammatory process in that termination and resolution of inflammation. In the acute inflammation, these lipid mediators limit polymorphonuclear cells infiltration, proinflammatory cytokine production; promote efferocytosis, and regulate several cell types being important roles in innate and adaptive immunity. Any dysregulation or defect of the resolution phase result in prolonged, persistent inflammation and eventually fibrosis. Resolvins are implicated in the development of various chronic autoimmune diseases. Systemic sclerosis (SSc) is a very complicated, chronic autoimmune disorder proceeding with vasculopathy, inflammation, and fibrosis. Dysregulation of innate and adaptive immunity is another important contributing factor in the pathogenesis of SSc. In this review, we will focus on the different roles of this new family of lipid mediators, characterized by the ability to prevent the spread of inflammation and its chronicity in various ways and how they can control the development of fibrotic diseases like SSc.

Raynaud Phenomenon in Systemic Sclerosis: Does Digital Thermal Monitoring Correlate to Specific Nailfold Videocapillaroscopy Abnormalities?

OBJECTIVE

Early diagnosis of systemic sclerosis (SSc) is imperative, and Raynaud phenomenon (RP) is an important component of progressive vasculopathy. Nailfold videocapillaroscopy (NVC) is a well-established tool that can quantify structural vascular abnormalities. Digital thermal monitoring (DTM) assesses microvascular functional dysfunction related to thermoregulation. In this study, we investigated the correlation of NVC patterns and DTM variables in patients with SSc.

METHODS

Patients with SSc according to the 2013 American College of Rheumatology/European League Against Rheumatism criteria who consented and enrolled in the clinical care registry had NVC and DTM performed. For NVC, the number of capillaries (density), measurement of apical diameter (dimension), presence or absence of hemorrhages, and number of abnormal shapes were assessed to categorize 3 different qualitative patterns: early, active, and late. For DTM, Doppler ultrasound hyperemic, low frequency, blood velocity of radial artery, and fingertip vascular function were assessed, and a vascular reactivity index (VRI) measurement was automated. Statistical evaluation was performed by nonparametric tests to assess the correlation of NVC and VRI.

RESULTS

Thirty-one SSc subjects with interpretable NVC and DTM performed on the same day were included in the study. VRI was progressively higher in SSc patients with early, active, and late NVC patterns of microangiopathy (P < 0.0001). There was a significant negative correlation between VRI and microhemorrhages scores (r = -0.363, P = 0.044).

CONCLUSION

Our study suggests that more advanced vasculopathy correlates to reduced microvascular function as detected by DTM and more advanced structural abnormalities detected by NVC. NVC and DTM may provide different aspects of vasculopathy quantification and complement each other as investigative tools.

Cooling-induced dilatation of cutaneous arteries is mediated by increased myoendothelial communication

Cold exposure causes cutaneous vasoconstriction via a reflex increase in sympathetic activity and a local effect to augment adrenergic constriction. Local cooling also initiates cutaneous dilatation, which may function to restrain cold-induced constriction. However, the underlying mechanisms and physiological role of cold-induced dilatation have not been defined. Experiments were performed to assess the role of endothelial-derived mediators in this response. In isolated pressurized cutaneous mouse tail arteries, cooling (28°C) did not affect the magnitude of dilatation to acetylcholine in preconstricted arteries. However, inhibition of nitric oxide (NO) [N^G-nitro-l-arginine methyl ester (l-NAME)] and prostacyclin (PGI₂) (indomethacin) reduced acetylcholine-induced dilatation at 37°C but not at 28°C, suggesting that cooling increased NO/PGI₂-independent dilatation. This NO/PGI₂-independent dilatation was reduced by inhibition of endothelial SK (UCL1684) and IK (TRAM34) Ca²⁺-activated K⁺-channels (K_Ca), consistent with endothelium-derived hyperpolarization (EDH). Cooling also increased dilatation to direct activation of K_Ca channels (SKA31, CyPPA) but did not affect dilatation to exogenous NO (DEA-NONOate). This cooling-induced increase in EDH-type dilatations was associated with divergent effects on potential downstream EDH mechanisms: cooling reduced dilatation to K⁺, which mimics an intercellular K⁺ cloud, but increased direct communication between endothelial and smooth muscle cells (myoendothelial coupling), assessed by cellular transfer of biocytin. Indeed, inhibition of gap junctions (carbenoxolone) abolished the EDH-type component of dilatation to acetylcholine during cooling but did affect NO-dominated dilatation at 37°C. Cooling also inhibited U46619 constriction that was prevented by inhibition of IK and SK K_Ca channels or inhibition of gap junctions. The results suggest that cooling dilates cutaneous arteries by increasing myoendothelial communication and amplifying EDH-type dilatation.NEW & NOTEWORTHY Cold causes cutaneous vasoconstriction to restrict heat loss. Although cold also initiates cutaneous dilatation, the mechanisms and role of this dilatation have not been clearly defined. This study demonstrates that cooling increases myoendothelial coupling between smooth muscle and endothelial cells in cutaneous arteries, which is associated with increased endothelium-derived hyperpolarization (EDH)-type dilatation. Dysfunction in this process may contribute to excessive cold-induced constriction and tissue injury.

Current and Future Outlook on Disease Modification and Defining Low Disease Activity in Systemic Sclerosis

Systemic sclerosis (SSc) is an autoimmune rheumatic disease with heterogeneous clinical manifestations and a variable course in which the severity of the pathology dictates the disease prognosis and course. Among autoimmune rheumatic diseases, SSc has the highest mortality rate among all rheumatic diseases, though there are exciting new therapeutic targets that appear to halt the progression of SSc manifestations such as skin or lung fibrosis. In selected patients, high-intensity regimens with autologous stem cell transplantation can favorably modify the course. In what was once thought to be an untreatable disease, targeted therapies have now changed the outlook of SSc to a treatable disorder. Herein, we discuss the targeted therapies modifying the outlook on selected organ involvement and creating opportunities for future treatment. We also present a framework for defining low disease activity in SSc.

Pain Intensity, Pressure Pain Hypersensitivity, Central Sensitization, and Pain Catastrophizing Related to Vascular Alterations in Raynaud's Phenomenon: A Preliminary Case-Control Study

OBJECTIVE

To evaluate pain intensity, widespread pressure pain, central sensitization (CS), and catastrophizing between subjects with primary and secondary Raynaud's phenomenon (RP) and healthy controls and to compare the relationships between vascular impairment and pain perception.

METHODS

A preliminary case-control study was performed with a total sample of 57 participants (37 with RP). Sociodemographic data, clinical/vascular data, and pain variables (pain intensity, pressure pain sensitivity, pain magnitude and threshold, CS, and catastrophizing) were registered. Results were analyzed by analysis of covariance and Pearson correlation.

RESULTS

Participants with RP had a lower basal temperature (more vasoconstriction) in their hands (P ≤ 0.012), higher pain intensity (P ≤ 0.001), higher electrical pain magnitude (P < 0.001), and lower pressure pain (P ≤ 0.05) and electrical pain (P < 0.001) thresholds in comparison with healthy controls. Secondary RP participants showed a significantly higher level of CS compared with controls and primary RP participants (P = 0.001). Catastrophizing was higher in the primary and secondary RP (P ≤ 0.001) groups than in controls. No correlations were observed between severity of vasoconstriction and pain variables.

CONCLUSIONS

RP participants showed bilateral hypersensitivity to pressure pain. However, the severity of vascular alterations seems not to be related to central pain experiences. Additional mechanisms such as catastrophizing may influence pain in RP; nevertheless, central sensitization only appears to be involved in the secondary form of RP.

Improvement of peripheral vascular impairment by a phosphodiesterase type 5 inhibitor tadalafil prevents oxaliplatin-induced peripheral neuropathy in mice

Oxaliplatin, a platinum-based chemotherapeutic drug, frequently induces peripheral neuropathy. Accumulating evidences suggest a possible relationship between peripheral vascular impairment and peripheral neuropathy. In this study, we investigated the effects of vasodilators on cumulative peripheral neuropathy induced by repeated injections of oxaliplatin (10 mg/kg) once a week for 8 weeks in mice. Single injections of vasodilators, including a phosphodiesterase type 5 inhibitor tadalafil acutely alleviated oxaliplatin-induced cold hypersensitivity, while tadalafil had no effect on the mechanical hypersensitivity. By contrast, long-term administration of tadalafil (0.1% in chow diets) during the oxaliplatin injection period reduced the oxaliplatin-induced decreases in skin temperature and blood flow without affecting platinum concentrations in blood, sciatic nerves, and dorsal root ganglion. The long-term administration significantly suppressed cold, mechanical, and electrical current hypersensitivities as well as thermal hypoesthesia. Furthermore, it prevented the decreases in sensory nerve conductance velocity and the number of endoneurial microvessels, and axon degeneration in the sciatic nerves. In vitro studies confirmed that tadalafil does not interfere with the cytotoxicity of oxaliplatin against human cancer cell lines. Altogether, these results suggest that improvement of peripheral vascular impairment by tadalafil could alleviate and prevent oxaliplatin-induced peripheral neuropathy.

Raynaud's phenomenon manifesting as progressive abnormal MRI bone marrow signal in the toes

Objective

The purpose of this report is to discuss the presentation and the progressive magnetic resonance imaging (MRI) findings in a single patient with clinically-diagnosed Raynaud's phenomenon (RP).

Conclusion

RP can present as non-specific toe pain and manifest as progressive abnormal MRI bone marrow signal in the toes. In addition to patient presentation and clinical assessment, this information could contribute to earlier diagnosis and treatment of RP and other coexisting rheumatologic disorders.