Patch Testing for Metal Allergy With Manufacturer-Supplied Materials Before Nuss Bar Insertion

Contact Dermatitis From Biomedical Devices, Implants, and Metals-Trouble From Within

Allergic contact dermatitis is characterized by its appearance of red, raised and infiltrated, scaling or scabbed skin and intense pruritus, and distinguished from irritant contact dermatitis by its specific immune process and histopathology. Many contact allergens are low-molecular- weight chemicals including metals such as nickel, cobalt, and chromium, preservatives, and adhesives. When such materials are used internally in biomedical devices, they are similarly capable of causing sensitization and an inflammatory response. Sometimes, the reaction remains internal, and presents as swelling, pain, stiffness, decreased range of motion, and internal itching around the implant. Such reactions may, in some cases, also extend to include a localized or, rarely, systemic contact dermatitis indicative of the same process. This review will present an overview of reported skin and local internal reactions to orthopedic implants, which are the largest category of implanted internal metal devices. Immune reactions to smaller categories of medical appliances include cardiac devices and vascular stents, neuromodulation devices, diabetic appliances, Nuss bar surgery for pectus excavatum, and dental and spinal implants. We will review the available diagnostic tools, the consensus on interpretation, and reported strategies for treatment.

Metal implant allergy: A retrospective cohort analysis at a university allergy practice

Background: Concern of metal sensitization in pre- and postsurgical evaluation is growing, with the recent guidelines remaining the criterion standard for consideration of patch testing. Information remains scarce on surgical screening in the groups of patients who reported a history of metal sensitivity versus those with no reported history. Objective: The objective of this study was to assess the utility of patch testing in surgical candidates based on reported metal allergy history. The secondary objective was to evaluate the utility and outcomes in postsurgical patch testing. Methods: Nine hundred and thirty-one patient charts of patients with the diagnosis of "contact dermatitis" who underwent an evaluation at a single allergy clinic site between January 2013 and December 2022 were identified and reviewed as part of a retrospective chart review study. Patients were included in subgroups based on the time of patch testing and history of reported metal allergy. Results: In all, 67 patients underwent patch testing, 10 (14.9%) of whom were surgical candidates without a history of metal sensitivity, 31 (46.2%) of whom were surgical candidates with a history of metal sensitivity, and 26 (38.8%) of whom were postsurgical patients. Twenty-nine (43.3%) of patients had positive patch testing results, with only one (10%) in the presurgical group, 17 (54.8%) in the presurgical with a history of metal sensitivity, and 11 (42.3%) in the postsurgical group. Zero patients in our cohort without metal sensitivity who were undergoing the Nuss procedure had positive reactions on patch testing, whereas two of four (50%) with reported metal sensitivity who were undergoing the Nuss procedure had positive relevant metal reactions. Conclusion: Ambiguity in the utility of patch testing for surgical decision making remains, despite common utilization. Recent guidelines along with coordination of care among the surgeon, allergist, and patient remains the criterion standard of care.

Preoperative Metal Patch Testing and Titanium Bar Use Criteria in Nuss Procedure: A 56-Patients' Cohort Study

INTRODUCTION

 Nuss procedure is the main reason for metal implants use by pediatric and thoracic surgeons. There is an ongoing debate on how to avoid allergic complications. Herein we describe our 8-year experience with systematic preoperative metal patch testing and our selective titanium bar use in Nuss procedure.

MATERIALS AND METHODS

 This is a single center retrospective observational cohort study of patients who underwent the Nuss procedure from 2013 to 2020. Preoperative metal patch testing was done in all cases. Criteria for titanium bar utilization were: a positive test for a major component of the stainless-steel bar; or a positive metal patch test and a positive history of atopy, food or metal allergy, or previous allergic reaction to an implant or device.

RESULTS

 In total, 56 patients were included. Most were male (91.1%) with a median age of 15.0 (13.0-22.0) years old. 19.6% had a positive preoperative metal patch test and 54.5% of these had no personal history of atopy. Stainless-steel bars were used in 27.3% of those patients and titanium bars were used in 72.7%. One patient had a documented minor allergy reaction. None of the 56 patients required early bar removal.

CONCLUSION

 Our study suggests that routine preoperative allergy testing and a judicious use of titanium bar are safe and avoid metal allergic complications.

Nickel contamination after minimally-invasive repair of pectus excavatum persists after bar removal

BACKGROUND

Minimally-invasive repair of pectus excavatum (MIRPE) has been shown to be associated with high release of trace metals into patient's body. The aim of our study was to analyze the kinetics of metal contamination after MIRPE and after bar removal.

METHODS

We prospectively assessed nickel and chromium changes in blood, urine, and local tissue in patients undergoing MIRPE with stainless-steel bar(s). Baseline samples were taken prior to surgery, further samples were taken at six defined time points until 30 months after bar removal. Clinical symptoms were evaluated at the time of every sample collection.

RESULTS

28 patients were included (mean age 16.4 years). At four weeks after MIRPE and persisting up to bar removal, we found significantly elevated trace metal levels in blood and urine. Tissue nickel and chromium levels were significantly elevated at the time of bar removal. After bar removal, the concentration of trace metal in urine and the concentration of chromium in plasma decreased gradually. In contrast, nickel levels in blood further increased. Five patients showed irritative symptoms after MIRPE, all symptomatic patients had elevated metal levels.

CONCLUSIONS

Following MIRPE, we found a rapid systemic increase of nickel and chromium. Our data indicate that trace metal release could cause irritative symptoms. The prolonged elevated systemic nickel levels beyond bar removal necessitate further investigations of the long-term side effects of MIRPE.

Utility of routine patch testing prior to surgical repair of pectus excavatum: A multidisciplinary experience via retrospective review at a single tertiary care center

BACKGROUND

The Nuss procedure is the only implant procedure in which routine, rather than selective, preoperative patch testing is recommended. This practice has recently been called into question.

OBJECTIVE

To evaluate an updated experience of pre-implant patch testing in patients undergoing the Nuss procedure.

METHODS

A retrospective chart review of Nuss procedures from 2012 through 2020.

RESULTS

Forty-five patients were identified for data collection. From 2012 to 2014, none of the 14 patients were patch tested. From 2015 to 2020, 26 of 31 (83.9%) were patch tested. Of those tested, only 2 had a positive patch test. A hypoallergenic titanium bar was inserted in each case. In total, there were zero bar reactions.

CONCLUSION

The risks of patch testing are extremely small and should be weighed against the serious implications of even one bar allergy when deciding on future guidelines.

Metal allergy after the Nuss procedure for pectus excavatum: a review

Minimally invasive repair of pectus excavatum (MIRPE) technique (the Nuss procedure) is a minimally-invasive method that is commonly used in the treatment of pectus excavatum. An allergic reaction to the metal alloy bar that is implanted in the thorax during the procedure is a reported complication. We briefly review current literature concerning epidemiology, mechanisms and research results of allergic reactions after Nuss bar implantation. This allergic reaction occurs in approximately 2.7% of patients and is caused by metals used in the medical implant. The most common symptoms include fever and skin lesions such as allergic dermatitis. Elevated levels of C-reactive protein is a frequent finding in laboratory tests. In order to minimize the risk of such complications, taking a detailed allergy-based medical history and conducting allergy tests, i.e. patch test are required. Allergic reactions can be managed with conservative treatment such as general or topical glucocorticosteroid therapy and antihistamine agents. Severe allergic reactions can be addressed by implant revision, replacement of the steel bar with a titanium substitute or removal of the stabilization at all. Although the risk of an allergic reaction to titanium is smaller it still exists, the titanium substitute is not routinely used due to its higher cost and lesser plasticity which has a negative impact on matching a stabilizing bar during the surgery. Surgeons treating pectus excavatum should remember about the possible allergic reactions after implantation of the metal bar and be familiar with methods of diagnosis and treatment of those complications.

Nickel Allergic Contact Dermatitis: Identification, Treatment, and Prevention

Nickel is a ubiquitous metal added to jewelry and metallic substances for its hardening properties and because it is inexpensive. Estimates suggest that at least 1.1 million children in the United States are sensitized to nickel. Nickel allergic contact dermatitis (Ni-ACD) is the most common cutaneous delayed-type hypersensitivity reaction worldwide. The incidence among children tested has almost quadrupled over the past 3 decades. The associated morbidities include itch, discomfort, school absence, and reduced quality of life. In adulthood, individuals with Ni-ACD may have severe disabling hand eczema. The increasing rate of Ni-ACD in children has been postulated to result from early and frequent exposure to metals with high amounts of nickel release (eg, as occurs with ear piercing or with products used daily in childhood such as toys, belt buckles, and electronics).To reduce exposure to metal sources with high nickel release by prolonged and direct contact with human skin, Denmark and the European Union legislated a directive several decades ago with the goal of reducing high nickel release and the incidence of Ni-ACD. Since then, there has been a global reduction in incidence of Ni-ACD in population-based studies of adults and studies of children and young adults being tested for allergic contact dermatitis. These data point to nickel exposure as a trigger for elicitation of Ni-ACD and, further, provide evidence that legislation can have a favorable effect on the economic and medical health of a population.This policy statement reviews the epidemiology, history, and appearances of Ni-ACD. Examples of sources of high nickel release are discussed to highlight how difficult it is to avoid this metal in modern daily lives. Treatments are outlined, and avoidance strategies are presented. Long-term epidemiological interventions are addressed. Advocacy for smarter nickel use is reviewed. The American Academy of Pediatrics supports US legislation that advances safety standards (as modeled by the European Union) that protect children from early and prolonged skin exposure to high-nickel-releasing items. Our final aim for this article is to aid the pediatric community in developing nickel-avoidance strategies on both individual and global levels.

Utility of Patch Testing and Lymphocyte Transformation Testing in the Evaluation of Metal Allergy in Patients with Orthopedic Implants

Total joint arthroplasties are increasingly common orthopedic procedures performed throughout the United States. Implant failure after these procedures occurs due to a number of causes such as infection or mechanical problems, with metal hypersensitivity being an area of growing interest. The nature and mechanism of a causative relationship between metal hypersensitivity and implant failure have been unclear as it is not known whether implant failure occurs due to a previous metal allergy or metal allergy results from secondary sensitization via metal exposure in existing failing implants. Overall, there appears to be growing support and evidence for metal-hypersensitive patients having worse outcomes with regard to total hip and knee arthroplasties. However, there are conflicting recommendations (outside of Nuss procedures) for pre-implant testing for metal hypersensitivity as testing has not consistently been shown to change patient outcomes.

Patch Testing for the Evaluation of Metal Hypersensitivity in the Nuss Procedure

The Nuss procedure has become the predominant reason for the use of metal implants by pediatric general and thoracic surgeons. Current guidelines recommend preimplant testing for all patients undergoing the Nuss procedure, which differs from the guidelines for all other orthopedic procedures. This review was done to further evaluate this discrepancy.

Patch Testing for Evaluation of Hypersensitivity to Implanted Metal Devices: A Perspective From the American Contact Dermatitis Society

The American Contact Dermatitis Society recognizes the interest in the evaluation and management of metal hypersensitivity reactions. Given the paucity of robust evidence with which to guide our practices, we provide reasonable evidence and expert opinion-based guidelines for clinicians with regard to metal hypersensitivity reaction testing and patient management. Routine preoperative evaluation in individuals with no history of adverse cutaneous reactions to metals or history of previous implant-related adverse events is not necessary. Patients with a clear self-reported history of metal reactions should be evaluated by patch testing before device implant. Patch testing is only 1 element in the assessment of causation in those with postimplantation morbidity. Metal exposure from the implanted device can cause sensitization, but a positive metal test does not prove symptom causality. The decision to replace an implanted device must include an assessment of all clinical factors and a thorough risk-benefit analysis by the treating physician(s) and patient.