Superficial femoral artery nitinol stent in a patient with nickel allergy

Nickel-related hypersensitivity reactions following endovascular interventions: A review of current evidence

INTRODUCTION

Nickel is a principal alloying agent in the production of vascular endoprostheses, despite persisting as the most habitually identified allergen. Variable nickel-related hypersensitivity manifestations following endovascular intervention were reported, challenging established paradigms in treatment and accuracy of prognostic assessments. The objective of this review is to critically evaluate current metrics to maximise patient-related outcomes.

METHODS

A literature review was conducted in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2009 statement. Patients indicative of nickel hypersensitivity reaction following endovascular intervention were discerned. A positive reaction was defined by patch testing, histological analysis, or anamnesis indicative of nickel hypersensitivity. Morphology of implicating prostheses, adverse events and postoperative complications, clinical course, diagnostic and therapeutic strategies alongside patient prognosis were recorded.

RESULTS

Nickel-related hypersensitivity reactions following endovascular repair were identified in 36 patients with a median age of 44.5 years. 20 patients received nitinol-containing intervention. 28 (77.8%) patients are female. Multi-organ adverse reactions occurred in 21 (58.3%) patients with variable latency. 14 (38.9%) patients were presented with neurological adverse reactions manifesting mainly as unilateral hemiparesis. Dermatological reactions implicated 16 (44.4%) patients. Miscellaneous manifestations include suicidal ideation. 13 (36.1%) patients displayed previous metal intolerance and 32 (88.9%) patients had positive patch testing for nickel. Histological analysis of lesions and prostheses indicated lymphocytic infiltration. 5 (13.9%) patients experienced device-specific reactions as in-stent restenosis or auxiliary distal vessel stenosis. 11 (30.1%) patients received solely medical therapy and 5 (13.9%) patients received solely surgical therapy. 19 (52.7%) patients underwent both medical (oral corticosteroid) and surgical therapy (device retrieval). 26 (77.1%) patients achieved symptomatic cessation, 6 (16.7%) patients exhibited symptomatic persistence and 0 patients died.

CONCLUSION

Prophylactic pre-assessment for a history of metal allergy and consideration of prostheses alternatives is recommended to minimise reaction risk and severity. Despite nickel's predominant usage, information paucity urges additional studies to emphasise its implications and maximise patient outcomes.

Severe Symptomatic Nickel Allergy Following Stent-Graft Implantation Requiring Excision and External Iliac Artery Reconstruction

Although nickel allergy is a common cause of contact dermatitis, systemic reactions to nitinol stents are rare. A 61-year-old woman had presented with a nonhealing toe wound. Angiography revealed an external iliac artery stenosis, which was treated with a nitinol stent graft. However, she developed severe truncal pruritus, and within 3 months, her external iliac stent graft had thrombosed. Allergy testing revealed nickel sensitivity. After medical therapy had failed, stent graft removal was performed, resulting in complete resolution of her symptoms. The present case demonstrates a rare allergic reaction to the nitinol in commercially available stent grafts. Pruritus and rash are rare reactions to stenting; however, a nitinol allergy should be considered for patients with no other identifiable primary source.

Nickels and tines: the myth of nickel allergy in intracranial stents

BACKGROUND

Most intracranial stents contain nickel alloy, and nickel allergy or hypersensitivity is common. Neurological injury following endovascular treatment with a nickel containing intracranial stent has been reported in patients with purported nickel allergy, but it is unclear whether these reactions represent true nickel hypersensitivity. We quantified nickel release from commonly used intracranial stents to investigate whether such stents should be avoided in patients with nickel allergy.

METHODS

We examined nickel release from seven commonly used intracranial stents: Enterprise, LVIS Jr, Neuroform, Wingspan, Zilver, Pipeline Flex Embolization Device, and Surpass Evolve. We incubated each stent in human plasma-like media for 30 days. Dimethylglyoxime (DMG) spot testing was performed on each stent to detect released nickel at 0 and 30 days. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) was then used to quantify the nickel concentration of the media at 30 days. Nickel currency and nickel standard for atomic absorption spectrometry were used as positive controls.

RESULTS

DMG spot tests indicated nickel release only from nickel currency at 0 and 30 days of incubation. No nickel release was detected from any stent at 30 days using ICP-OES.

CONCLUSIONS

Nickel release from commonly used intracranial stents is negligible. These results suggest that previously reported hypersensitivity to these stents may be misattributed to nickel allergy, and that patients with nickel allergy may be safely treated with select nickel-containing stents.

Nickel hypersensitivity and endovascular devices: a systematic review and meta-analysis

OBJECTIVE

Nickel allergy is common; endovascular specialists are often confronted with nickel allergic patients ahead of the implantation of endovascular devices, many of which are nickel-containing. Our aim was to elucidate whether nickel hypersensitivity is significantly associated with worse or adverse outcomes after placement of a nickel-containing endovascular device.

METHODS

Inclusion criteria were: endovascular and transcatheter procedures for coronary, structural heart, neurovascular and peripheral vascular pathology involving nickel-allergic patients. All adverse outcomes were included as defined by included studies. A systematic review and meta-analysis were undertaken using a random-effects model. Searches of MEDLINE and EMBASE were conducted for articles published 1947-2019.

RESULTS

190 records were identified, 78 articles were included for qualitative synthesis and 15 met criteria for meta-analysis. Patch-test confirmed nickel allergy was associated with an increased risk of adverse outcomes following implantation of a nickel-containing endovascular device (n=14 articles, 1740 patients; OR 2.61, 95% CI 1.41 to 4.85). This finding further was observed in coronary (n=12 articles, 1624 patients; OR 1.94, 95% CI 1.16 to 3.23) and structural heart subgroups (n=2 articles, 83 patients; OR 52.28, 95% CI 1.31 to 2079.14), but not in the neurovascular subgroup (n=1 article, 33 patients; OR 3.04, 95% CI 0.59 to 15.72) or with a patient-reported history of nickel allergy (n=2 articles, 207 patients; OR 2.14, 95% CI 0.23 to 19.70).

CONCLUSIONS

Patch-tested nickel allergy is associated with an increased risk of adverse outcomes following endovascular device implantation and alternative treatment options should be considered. Specialists faced with patients' self-reporting nickel allergy should consider proceeding to diagnostic patch-testing.

Systemic Contact Dermatitis: The Routes of Allergen Entry

Systemic contact dermatitis (SCD) is a generalized reactivation of type IV hypersensitivity skin diseases in individuals with previous sensitization after a contact allergen is administered systemically. Patients with SCD may consider their dermatitis unpredictable and recalcitrant since the causative allergens are difficult to find. If a patient has a pattern of dermatitis suggestive of SCD but fails to improve with conventional treatment, SCD should be taken into consideration. If doctors are not familiar with the presentations of SCD and the possible routes of allergen sensitization and exposure, the diagnosis of SCD may be delayed. In this work, we summarized all of the routes through which allergens can enter the body and cause SCD, including oral intake, local contact (through skin, inhalation, nasal spray and anal application), implants, and other iatrogenic or invasive routes (intravenous, intramuscular, intraarticular, and intravesicular). This will provide a comprehensive reference for the clinicians to identify the culprit of SCD.

Pulmonary arteriovenous malformation with metal allergy

We present a rare case of single pulmonary arteriovenous malformation (PAVM) with multiple metal allergies, including for platinum. A 47-year-old woman presented to our hospital without any symptoms. Enhanced computed tomography showed a single PAVM in S6 of the right lung. Interviews prompted us to suspect a history of palmoplantar pustulosis associated with metal dental filling. Dermatology patch tests for metal allergy were positive for platinum, cobalt, tin and potassium dichromate. The first choice of treatment for PAVM is endovascular treatment using a metal coil. Since the coil is composed of platinum alloy, we performed partial lung resection for PAVM without metal implants. Although metal allergy is rare for endovascular treatment, it causes an additional stress of removal of causative metal or long-term steroidal treatment. Therefore, for single PAVM with multiple metal allergies to the implants, surgical treatment without metal implants should be considered.

Smart materials in cardiovascular implants: Shape memory alloys and shape memory polymers

Smart materials have intrinsic properties that change in a controlled fashion in response to external stimuli. Currently, the only smart materials with a significant clinical impact in cardiovascular implant design are shape memory alloys, particularly Nitinol. Recent prodigious progress in material science has resulted in the development of sophisticated shape memory polymers. In this article, we have reviewed the literature and outline the characteristics, advantages, and disadvantages of shape memory alloys and shape memory polymers which are relevant to clinical cardiovascular applications, and describe the potential of these smart materials for applications in coronary stents and transcatheter valves.

Metallic allergy requiring removal of iliac stent: report of a case

BACKGROUND

The use of metallic stents, which are predominantly composed of nickel, in the treatment of patients with nickel allergy has not been well studied.

CASE PRESENTATION

A patient who suffered from contact dermatitis due to implantation of an iliac stent was successfully treated by removing the stent that caused nickel allergy. The patient has exhibited no symptoms of claudication or severe pruritic rash in the 2-year follow-up period after iliac stent removal.

CONCLUSIONS

We herein report a case of nickel allergy in which a metallic iliac stent that was predominantly composed of nickel was removed. The patient showed a marked recovery from her contact dermatitis. In cases of suspected metallic allergy, it is necessary to consider revascularization without using a metal device.

Corrosion resistance of a Nitinol ocular microstent: Implications on biocompatibility

Nitinol is commonly used in medical implants due to its unique thermomechanical properties of shape memory and superelasticity. Free nickel has the potential to induce biological responses that may be a concern for permanent implants manufactured from nickel-containing alloys. Although there are extensive reports on the effects of surface treatments on corrosion behavior in cardiovascular Nitinol implants, there is a lack of data on corrosion resistance and impact on biocompatibility for ocular implants. Therefore, the objective of this study was to determine localized corrosion and nickel elution resistance of an electropolished Nitinol-based ocular device (Hydrus Microstent, Ivantis, Inc.) intended for patients with primary open angle glaucoma. Pitting corrosion susceptibility was characterized by potentiodynamic polarization testing per ASTM F2129. In addition, nickel ion release was quantified with immersion testing to 63 days. The results indicated high localized corrosion resistance as all samples reached polarization potentials of 800 mV without pitting initiation. Maximum nickel elution rates per device were less than approximately 1.1 ng/device/day after the first day of immersion and reduced to less than 0.1 ng/device/day after 7 days. For a patient with bilateral microstents, these nickel concentrations are ×10,000 lower than previously published tolerable intake levels for systemic toxicity. Overall, these corrosion results are in good agreement with literature values of well processed and biocompatible Nitinol devices indicating adverse systemic biological responses are not expected in vivo.

Impact of nitinol stent surface processing on in-vivo nickel release and biological response

Although nitinol is widely used in percutaneous cardiovascular interventions, a causal relationship between nickel released from implanted cardiovascular devices and adverse systemic or local biological responses has not been established. The objective of this study was to investigate the relationship between nitinol surface processing, in-vivo nickel release, and biocompatibility. Nitinol stents manufactured using select surface treatments were implanted into the iliac arteries of minipigs for 6 months. Clinical chemistry profile, complete blood count, serum and urine nickel analyses were performed periodically during the implantation period. After explant, stented arteries were either digested and analyzed for local nickel concentration or fixed and sectioned for histopathological analysis of stenosis and inflammation within the artery. The results indicated that markers for liver and kidney function were not different than baseline values throughout 180 days of implantation regardless of surface finish. In addition, white blood cell, red blood cell, and platelet counts were similar to baseline values for all surface finishes. Systemic nickel concentrations in serum and urine were not significantly different between processing groups and comparable to baseline values during 180 days of implantation. However, stents with non-optimized surface finishing had significantly greater nickel levels in the surrounding artery compared to polished stents. These stents had increased stenosis with potential for local inflammation compared to polished stents. These findings demonstrate that proper polishing of nitinol surfaces can reduce in-vivo nickel release locally, which may aid in minimizing adverse inflammatory reactions and restenosis.

STATEMENT OF SIGNIFICANCE

Nitinol is a commonly used material in cardiovascular medical devices. However, relationships between nitinol surface finishing, in-vivo metal ion release, and adverse biological responses have yet to be established. We addressed this knowledge gap by implanting single and overlapped nitinol stents with different surface finishes to assess systemic impact on minipigs (i.e. serum and urine nickel levels, liver and kidney function, immune and blood count) over the 6 month implantation period. In addition, nickel levels and histopathology in stented arteries were analyzed on explant to determine relationships between surface processing and local adverse tissue reactions. The findings presented here highlight the importance of surface processing on in-vivo nickel release and subsequent impact on local biological response for nitinol implants.

Nickel-Related Adverse Reactions in the Treatment of Cerebral Aneurysms: A Literature Review

BACKGROUND

Nickel is the most common metal allergen and predominantly affects women. It is also the ubiquitous component in the alloys used to manufacture intracranial devices for aneurysm treatments, including aneurysm clips, self-expanding stents, flow-diverting stents, and endosaccular occlusion devices. Adverse events related to nickel allergy after deployment of such devices are uncommon but can be severe, resulting in dilemmas in the choice of treatment strategies and devices in managing nickel-sensitive patients with intracranial aneurysms.

METHODS

A literature search was performed in accordance with the PRISMA guidelines to identify studies reporting on nickel-related adverse events in patients being treated for cerebral aneurysm. The materials of the culprit devices, clinical presentation, histological features, and treatments were reviewed. Clinical considerations and management options for nickel allergy patients were evaluated.

RESULTS

Nickel is a major component of the cobalt alloy used in aneurysm clips and also of nitinol, which is commonly used in flow diverters and intracranial stents. Our literature review identified 9 articles reporting 10 unique cases of nickel-related adverse events after aneurysm treatment. Five of the cases occurred after aneurysm clipping, and the other 5 were attributed to endovascular devices. Two patients presented with dermatologic manifestations and 8 with neurologic manifestations, including cerebral edema and cerebritis.

CONCLUSIONS

Neurologic complications related to nickel in cerebral aneurysm treatments are rare but remain concern owing to the high prevalence of nickel allergy in the population. Surgeons and interventionists should consider the metal allergy history and its potential clinical significance in managing nickel-allergic patients with aneurysms.

Systemic hypersensitivity reaction to endovascular stainless steel stent

Endovascular intervention has become the mainstay for treatment of most patients suffering from peripheral vascular disease. We describe a patient with a known nickel allergy who underwent placement of a stainless steel stent for aortoiliac occlusive disease. Despite our attempt to avoid a nickel-containing stent, the patient developed a diffuse rash consistent with a nickel or metal allergy. A review of stainless steel metallurgy revealed that nickel, cobalt, and titanium are frequently used to provide anticorrosive properties to stainless steel. The clinical significance of the use of nickel-alloy stents in the setting of patients with a nickel allergy is discussed.

The effects of surface processing on in-vivo corrosion of Nitinol stents in a porcine model

A major limitation with current assessments of corrosion in metallic medical devices is the lack of correlation between in-vitro and in-vivo corrosion performance. Therefore, the objective of this study was to elucidate the relationship between pitting corrosion measured by breakdown potentials (E_b) in ASTM F2129 testing and corrosion resistance in-vivo. Four groups of Nitinol stents were manufactured using different processing methods to create unique surface properties. The stents were implanted into iliac arteries of minipigs for six months and explanted for corrosion analysis. Scanning electron microscopy and energy dispersive X-ray spectrometry analyses indicated that stents with a thick complex thermal oxide (420nm) and high corrosion resistance in-vitro (E_b=975±94mV) were free from detectable corrosion in-vivo and exhibited no changes in Ni/Ti ratio when compared to non-implanted controls. This result was also found in mechanically polished stents with a thin native oxide (4nm; E_b=767±226mV). In contrast, stents with a moderately thick thermal oxide (130nm) and low corrosion resistance in-vitro (E_b=111±63mV) possessed corrosion with associated surface microcracks in-vivo. In addition, Ni/Ti ratios in corroded regions were significantly lower compared to non-corroded adjacent areas on explanted stents. When stents were minimally processed (i.e. retained native tube oxide from the drawing process), a thick thermal oxide was present (399nm) with low in-vitro corrosion resistance (E_b=68±29mV) resulting in extensive in-vivo pitting. These findings demonstrate that functional corrosion testing combined with a detailed understanding of the surface characteristics of a Nitinol medical device can provide insight into in-vivo corrosion resistance.

STATEMENT OF SIGNIFICANCE

Nitinol is a commonly used material in the medical device industry. However, correlations between surface processing of nitinol and in-vivo corrosion has yet to be established. Elucidating the link between in-vivo corrosion and pre-clinical characterization can aid in improved prediction of clinical safety and performance of nitinol devices. We addressed this knowledge gap by fabricating nitinol stents to possess distinct surface properties and evaluating their corrosion susceptibility both in-vitro and after six months of in-vivo exposure. Relationships between stent processing, surface characterization, corrosion bench testing, and outcomes from explanted devices are discussed. These findings highlight the importance of surface characterization in nitinol devices and provide in-vitro pitting corrosion levels that can induce in-vivo corrosion in nitinol stents.

Current practices in corrosion, surface characterization, and nickel leach testing of cardiovascular metallic implants

In an effort to better understand current test practices and improve nonclinical testing of cardiovascular metallic implants, the Food and Drug Administration (FDA) held a public workshop on Cardiovascular Metallic Implants: corrosion, surface characterization, and nickel leaching. The following topics were discussed: (1) methods used for corrosion assessments, surface characterization techniques, and nickel leach testing of metallic cardiovascular implant devices, (2) the limitations of each of these in vitro tests in predicting in vivo performance, (3) the need, utility, and circumstances when each test should be considered, and (4) the potential testing paradigms, including acceptance criteria for each test. In addition to the above topics, best practices for these various tests were discussed, and knowledge gaps were identified. Prior to the workshop, discussants had the option to provide feedback and information on issues relating to each of the topics via a voluntary preworkshop assignment. During the workshop, the pooled responses were presented and a panel of experts discussed the results. This article summarizes the proceedings of this workshop and background information provided by workshop participants. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. J Biomed Mater Res Part B: Appl Biomater, 105B: 1330-1341, 2017.

Severe generalized dermatitis in a nickel-allergic patient with a popliteal artery nitinol stent

We present the case of a patient who developed a full-body desquamating macular-papular, pruritic rash after endovascular placement of a popliteal artery nitinol stent for acute limb ischemia. The rash was resistant to high-dose steroid and immunosuppressive treatment and intensive topical treatment. Patch testing revealed nickel allergy. The stented arterial segment was removed, with significant improvement in his symptoms that allowed the cessation of prednisone and topical treatments. The epidemiology, pathophysiology, and clinical effect of nickel allergy are discussed in addition to the use of nickel-alloy stents.

Design, Manufacturing, and In Vitro Testing of a Patient-Specific Shape-Memory Expander for Nose Reconstruction With Forehead Flap Technique

Forehead skin is widely acknowledged as a good donor site for total nasal reconstruction, thanks to its matching color, texture, and abundant vascularity. The forehead flap technique uses an axial pattern flap forehead skin to replace missing nasal tissue. To increase the amount of available tissue and reduce the size of the tissue defect after flap mobilization, tissue expanders may be used. Although this is a relatively established technique, limitations include reduced moldability of the forehead skin (which is thicker than the nasal skin), and the need for multiple sessions of expansion to achieve a sufficient yield to close the forehead.Shape-memory metals, such as nitinol, can be programmed to "remember" complex shapes. In this work, the methodology for producing a prototype of nitinol tissue expander able to mold the skin in a predetermined patient-specific skin shape is described. A realistic nose mold was manufactured using metal rapid prototyping; nitinol sheet and mesh were molded into nose-shape constructs, having hyperelastic as well as shape-memory capability. Computed tomography scanning was performed to assess the ability of the structure to regain its shape after phase transformation upon cooling within 2% of initial dimensions. The prototypes were implanted in a pig forehead to test its ability to impose a nose shape to the forehead skin.The shape-memory properties of nitinol offer the possibility of producing bespoke tissue expanders able to deliver complex, precisely designed skin envelopes. The hyperelastic properties of nitinol allow constant preprogrammed expansion forces to be generated throughout the expansion process.

Allergy to Surgical Implants

Surgical implants have a wide array of therapeutic uses, most commonly in joint replacements, but also in repair of pes excavatum and spinal disorders, in cardiac devices (stents, patches, pacers, valves), in gynecological implants, and in dentistry. Many of the metals used are immunologically active, as are the methacrylates and epoxies used in conjunction with several of these devices. Allergic responses to surgical components can present atypically as failure of the device, with nonspecific symptoms of localized pain, swelling, warmth, loosening, instability, itching, or burning; localized rash is infrequent. Identification of the specific metal and cement components used in a particular implant can be difficult, but is crucial to guide testing and interpretation of results. Nickel, cobalt, and chromium remain the most common metals implicated in implant failure due to metal sensitization; methacrylate-based cements are also important contributors. This review will provide a guide on how to assess and interpret the clinical history, identify the components used in surgery, test for sensitization, and provide advice on possible solutions. Data on the pathways of metal-induced immune stimulation are included. In this setting, the allergist, the dermatologist, or both have the potential to significantly improve surgical outcomes and patient care.

Allergic Reaction following Implantation of a Nitinol Alloy Inferior Vena Cava Filter

A 67-year-old woman developed severe pruritus after implantation of a retrievable nitinol inferior vena cava (IVC) filter (55.4% nickel and 44.6% titanium). The pruritus resolved only after filter retrieval. The patient's hypersensitivity to nickel was confirmed by a positive skin patch test substantiating a systemic allergic reaction to the implanted nitinol IVC filter.

Contact dermatitis: a practice parameter-update 2015

This parameter was developed by the Joint Task Force on Practice Parameters, which represents the American Academy of Allergy, Asthma & Immunology (AAAAI); the American College of Allergy, Asthma & Immunology (ACAAI); and the Joint Council of Allergy, Asthma & Immunology. The AAAAI and the ACAAI have jointly accepted responsibility for establishing "Contact Dermatitis: A Practice Parameter-Update 2015." This is a complete and comprehensive document at the current time. The medical environment is changing and not all recommendations will be appropriate or applicable to all patients. Because this document incorporated the efforts of many participants, no single individual, including members serving on the Joint Task Force, are authorized to provide an official AAAAI or ACAAI interpretation of these practice parameters. Any request for information or interpretation of this practice parameter by the AAAAI or ACAAI should be directed to the Executive Offices of the AAAAI, the ACAAI, and the Joint Council of Allergy, Asthma & Immunology. These parameters are not designed for use by the pharmaceutical industry in drug development or promotion. Previously published practice parameters of the Joint Task Force on Practice Parameters for Allergy & Immunology are available at http://www.JCAAI.org or http://www.allergyparameters.org.

Dermatitis caused by metal allergy after coil embolization for unruptured cerebral aneurysm

We report a rare case of metal-induced dermatitis after coil embolization for cerebral aneurysm. A 51-year-old woman experienced a rash around the lips and neck 3 weeks after coil embolization. Judging from the clinical course and results of several patch tests, platinum coils were considered to have induced the dermatitis. Symptoms were relieved with administration of oral steroids. This represents the first report of metal-induced dermatitis after neuroendovascular treatment. The possibility of metal allergy was difficult to suspect preoperatively. However, early evaluation and referral are important when skin symptoms are observed postoperatively.

Dermatitis caused by metal allergy after coil embolization for unruptured cerebral aneurysm

We report a rare case of metal-induced dermatitis after coil embolization for cerebral aneurysm. A 51-year-old woman experienced a rash around the lips and neck 3 weeks after coil embolization. Judging from the clinical course and results of several patch tests, platinum coils were considered to have induced the dermatitis. Symptoms were relieved with administration of oral steroids. This represents the first report of metal-induced dermatitis after neuroendovascular treatment. The possibility of metal allergy was difficult to suspect preoperatively. However, early evaluation and referral are important when skin symptoms are observed postoperatively.

Hypersensitivity to nickel in a patient treated with coil embolization for pelvic congestion syndrome

A 34-year-old woman had persistent symptoms of pelvic venous congestion syndrome and developed new symptoms of a systemic allergic reaction after coil embolization of both ovarian and internal iliac veins. Patch testing revealed hypersensitivity to nickel and palladium, both components of the coils used. After surgical removal of the coils and hysterectomy with salpingo-oophorectomy, all her symptoms resolved.