A literature review and expert consensus statement on diagnostics in suspected metal implant allergy

BACKGROUND

Although rare, allergic reactions to metal implants represent a diagnostic challenge in view of missing guidelines.

OBJECTIVES

To develop an European expert consensus on characteristics of metal allergy reactions and the utility of various diagnostic tools in suspected metal implant allergy.

METHODS

A nominal group technique (NGT) was applied to develop consensus statements. Initially an online literature database was created on a secure server to enable a comprehensive information. Twenty-three statements were formulated on potential aspects of metal implant allergy with a focus on diagnostics and grouped into five domains. For the consensus development, the panel of 12 experts initially did refine and reformulate those statements that were ambiguous or had unclear wording. By face-to-face (9/12) or virtual participation (3/12), an anonymous online voting was performed.

RESULTS

Consensus (≥80% of agreement) was reached in 20/23 statements. The panel agreed that implant allergy despite being rare should be considered in case of persistent unexplained symptoms. It was, however, recommended to allow adequate time for resolution of symptoms associated with healing and integration of an implant. Obtaining questionnaire-aided standardized medical history and standardized scoring of patient outcomes was also considered an important step by all experts There was broad consensus regarding the utility/performance of patch testing with additional late reading. It was recognized that the lymphocyte transformation test (LTT) has to many limitations to be generally recommended. Prior to orthopaedic implant, allergy screening of patients without a history of potential allergy to implant components was not recommended.

CONCLUSIONS

Using an expert consensus process, statements concerning allergy diagnostics in suspected metal implant allergy were created. Areas of nonconsensus were identified, stressing uncertainty among the experts around topics such as preoperative testing in assumed allergy, histological correlate of periimplant allergy and in vitro testing, which underscores the need for further research.

Patch Test Results and Outcome in Patients with Complications from Total Knee Arthroplasty: A Consecutive Case Series

The role of hypersensitivity in implant-related complications remains controversial. The objectives of our study were to (1) establish the prevalence of hypersensitivity to components of knee prostheses in patients referred to our contact dermatitis clinic, (2) determine if patients with post-surgery dermatitis have become sensitized, and (3) describe the outcome of patients with and without hypersensitivity. We reviewed the charts of patients referred from 2007 to 2018 and extracted demographic information, date, type, and site of implant, clinical presentation, and results of patch testing (PT) or lymphocyte transformation tests (LTT). We called most patients to gather data such as clinical outcome, nature, and timing of additional surgery. Statistical analysis included computation of conventional descriptive statistics. Because of the type of study design, only some categorical variables were tested for possible associations by analytical tools (cross-tabulation). Thirty-nine patients, 23 men (59.0%), and 16 women (41.0%), were included. Their mean age in years was 63.3 (95% confidence interval [CI]: 60.9-65.7) ranging from 39.0 to 79.0, (standard deviation) = 9.69, without statistically significant differences between males and females. Five patients had positive PT possibly relevant to their implant. Four patients had revision surgery and two improved. Of nine patients with dermatitis, one with relevant PT did not improve after revision, and the dermatitis was unrelated to TKA in eight. Of the 26 patients without dermatitis or relevant PT results, 9 had revisions because of incapacitating symptoms, and 5 improved. Hypersensitivity to implant components is a potential factor in the etiology of TKA complications. Patients with confirmed hypersensitivity may benefit from revision. Our study, however, did not detect statistically significant differences in outcome of revision surgery between patients with positive versus negative PT or LTT. In spite of this, we consider that patients with a history suggestive of metal, acrylate or aminoglycoside allergy should be tested preoperatively to avoid hypersensitivity-related postoperative complications. In the absence of hypersensitivity, some patients with incapacitating symptoms may also improve following revision.

Reticular telangiectatic erythema by breast implants

Reticular telangiectatic erythema is a benign dermatosis which has been described on patients with pacemakers, implantable devices or materials inserted in their body. Etiology of this entity hasn't been clarified since the first description in 1981 but it is suggested that physical or mechanical factors have to be involved.

We present the second case of bilateral reticular telangiectatic erythema by breast implants described in the literature.

Contact Urticaria to Nickel: A Series of 11 Patients Who Were Prick Test Positive and Patch Test Negative to Nickel Sulfate 2.5% and 5.0

BACKGROUND

Nickel is the most common allergen found by patch testing; however, not all cases of nickel allergy are type 4 (delayed) allergies. Contact urticaria (CU) to nickel (immediate reaction) has been reported; however, few seem to evaluate it as per a recent published survey of American Contact Dermatitis Society members.

OBJECTIVE

The aim of the study was to present a series of patients who had clinical histories suggestive of nickel allergy and yet were patch test negative but prick test positive to nickel, thus demonstrating CU.

METHODS

We reviewed the charts of 11 patients who were patch test negative but prick test positive.

RESULTS

All 11 patients demonstrated evidence of CU by prick testing (or closed chamber test in 1). None were patch test positive to nickel 2.5% or 5.0%. Four patients' histories mentioned reactions to various jewelry/earrings within minutes, whereas 2 histories mentioned reacting within a few hours. These histories are consistent with CU. Others (except 1 patient) recalled reacting to jewelry/earrings but did not recall a time frame.

CONCLUSIONS

Our series suggests that CU to nickel may be far more common than anticipated and should be evaluated with prick testing when patients' history suggests nickel allergy and yet they are patch test negative.

[Metal implant sensitivity: clinical and histological presentation]

Metal implant sensitivity (intolerance) can cause pain, reduced mobility, loosening of the implant and skin rashes. Knowledge of differential diagnoses, histology and appropriate diagnostics are essential for proper diagnosis. To outline typical clinical signs and histology in metal-implant-associated skin lesions we present three exemplary patients from our implant allergy outpatient department and give an overview of the current literature regarding metal implant sensitivity. In patients with a negative patch test the lymphocyte transformation test may reveal metal sensitization. Even "pure" titanium alloys may contain traces of nickel. The histology of implant-associated skin reactions goes from teleangiectatic postimplantation erythema to eczema and vasculitis. Based on the synopsis of history, clinical picture, allergological testing and histology, metal implant sensitivity can be diagnosed more precisely.

Reticular telangiectatic erythema: case report and literature review

Background:

Reticular telangiectatic erythema is a benign cutaneous reaction that may occur in patients who have received a subcutaneous implantable cardioverter-defibrillator. Reticular telangiectatic erythema is characterized by asymptomatic telangiectasias, blanchable erythematous patches, or both overlying and/or adjacent to the subcutaneous implantable cardioverter-defibrillator.

Purpose:

We describe a man who developed reticular telangiectatic erythema after receiving a subcutaneous implantable cardioverter-defibrillator and review the salient features of this condition. We also summarize the conditions that can mimic reticular telangiectatic erythema.

Materials and methods:

The features of a man with reticular telangiectatic erythema are presented and the literature on reticular telangiectatic erythema is reviewed.

Results:

Our patient developed reticular telangiectatic erythema within one month of subcutaneous implantable cardioverter-defibrillator insertion. The subcutaneous manifestations were asymptomatic. The patient concurred to have periodic clinical follow up and his condition will be monitored for any changes.

Conclusion:

Reticular telangiectatic erythema is a benign condition characterized by the development of erythema, telangiectasia, or both following insertion of a subcutaneous implantable cardioverter-defibrillator. Other subcutaneous implantable cardioverter-defibrillator-related side effects, such as pressure dermatitis and contact dermatitis, can mimic the condition. Reticular telangiectatic erythema can also be observed following insertion of other devices or, rarely, in the absence of inserted devices. Local microcirculatory changes and subcutaneous implantable cardioverter-defibrillator-related obstruction of blood flow have been suggested as possible mechanisms of pathogenesis. The diagnosis can usually be established by clinical presentation. Therefore, patch testing can usually be omitted. Reticular telangiectatic erythema is typically asymptomatic and thus removal of the device is not required.

Clinical and diagnostic challenges of metal implant allergy using the example of orthopaedic surgical implants: Part 15 of the Series Molecular Allergology

The focus of this review are allergic reactions to orthopaedic-surgical metal implants. The spectrum of metal implant associated potential allergic reactions encompasses eczema, impaired wound and fracture healing, infection-mimicking reactions, effusions, pain and loosening. Nickel, cobalt and chromium seem to be the predominant eliciting allergens. Despite the growing number of respective publications the topic „metal implant allergy“ remains a diagnostic challenge. Initially, differential diagnoses should always be excluded in cooperation with surgery collegues. It is recommended to perform a combined evaluation of medical history, clinical findings, patch testing and histology. The lymphocyte transformation test (LTT) can indicate metal sensitization, but it needs careful interpretation. Allergists can provide a substantial contribution to this interdisciplinary topic.

Heat-triggered reticular telangiectatic erythema induced by a spinal cord stimulator

In recent years, cutaneous complications have been reported after implantation of medical devices as a result of their widespread use. We report a case of reticular telangiectatic erythema (RTE) after replacement of a spinal cord stimulator. To date, the pathogenesis of RTE has been poorly understood. Some reports have suggested that heat is involved, whereas others seem to contradict this observation. In our thermographic study, we found that heat can cause RTE.