Study of biomaterial-induced macrophage activation, cell-mediated immune response and molecular oxidative damage in patients with dermal bioimplants

Oral Methotrexate Treatment of Delayed-Onset Inflammatory Reactions to Dermal Fillers

Background

In aesthetic practice, delayed-onset (late) inflammatory reactions (DIRs) to dermal fillers are encountered. The treatment of DIRs can be challenging, with a response to established therapies, including oral antibiotics, intralesional and oral steroids, and hyaluronidase injection, occasionally reported as unsatisfactory.

Objectives

Evaluate the efficacy of low-dose oral methotrexate (MTX) therapy in treating recalcitrant DIRs.

Methods

We retrospectively reviewed cases of recalcitrant DIRs treated with oral MTX. Data collected included individuals' gender and age, medical history, filler type, facial area(s) injected, previous treatments attempted to dissolve the DIR, MTX treatment dosage and duration, and outcome. Adverse events were monitored throughout the treatment.

Results

Thirteen females with a mean age of 52.6 years (range, 31-67 years) who developed recalcitrant DIRs to dermal filler injection are included. Eight reactions were triggered by the injection of hyaluronic acid (HA) fillers, 4 by liquid injectable silicone (LIS), and 1 by polymethylmethacrylate (PMMA). The average starting dosage of MTX was 12.1 mg/week (range, 7.5-12.5 mg/week). Patients were treated for 2 to 3 months in most cases. The average follow-up post-MTX therapy was 11.8 months (range, 2-36 months). A complete response to MTX treatment was observed in 10 patients (6 HA and 4 LIS cases), partial response in 1 (HA case), and an unsatisfactory response in 2 (HA and PMMA cases). Treatment was well tolerated.

Conclusions

A short course of low-dose oral MTX is a possible treatment for DIRs that have not responded to established therapies. The promising results of this report require validation by powered studies.

Level of Evidence 4

The chitinases as biomarkers in immune-mediate diseases

The role of chitinases has been focused as potential biomarkers in a wide number of inflammatory diseases, in monitoring active disease state, and predicting prognosis and response to therapies. The main chitinases, CHIT1 and YKL-40, are derived from 18 glycosyl hydrolases macrophage activation and play important roles in defense against chitin-containing pathogens and in food processing. Moreover, chitinases may have organ- as well as cell-specific effects in the context of infectious diseases and inflammatory disorders and able to induce tissue remodelling. The CHIT1 measurement is an easy, reproducible, reliable, and cost-effective affordable assay. The clinical use of CHIT1 for the screening of lysosomal storage disorders is quite practical, when proper cut-off values are determined for each laboratory. The potential of CHIT1 and chitinases has not been fully explored yet and future studies will produce many surprising discoveries in the immunology and allergology fields of research. However, since the presence of a null CHIT1 gene in a subpopulation would be responsible of false-negative values, the assay should be completed with the other markers such ACE and, if necessary, by genetic analysis when CHIT1 is unexpected low.

Complications following Permanent Filler Injection: A Prospective Cohort Study and Protocol of Management

Permanent filler (PF) substances are increasingly utilized in aesthetic procedures. Concurrently, complications related to fillers have also risen. This study aims to determine the rate of complications secondary to PF injections and develop a therapeutic approach for treating such complications.

METHODS

This cohort study was conducted by distributing a checklist form among all patients aged 18 years or older who arrived for a new cosmetic consultation between 2015 and 2019. The primary outcome was the occurrence of complications, which are defined as symptoms induced by the PF. The demographics, type of PF, injection site, the time for the complication to occur, and signs and symptoms were recorded and followed up.

RESULTS

In this study, 325 out of 503 (64.61%) patients presented with PF-related complications. About 92.8% were women. All patients with PF-related complications presented with a lump (n = 325, 100%). In regard to the anatomical area of injection, the most common areas were the cheeks (66.6%). The time it took for the complication to occur most commonly ranged from 1-5 years (39.2%, P < 0.001). Complications were significantly higher among patients who received the injection in a nonmedical facility (P < 0.0002). Seventy-seven cases (15.3%, P < 0.0001) underwent PF removal.

CONCLUSIONS

PF-related complications in the body exhibit a wide range of onset and adverse events. The best method to prevent complications caused by permanent filling materials is to avoid them altogether. When it comes to permanent filling agents, we suggest extreme caution.

The role of biomaterials and scaffolds in immune responses in regenerative medicine: macrophage phenotype modulation by biomaterial properties and scaffold architectures

Scaffolds are an integral part of the regenerative medicine field. The contact of biomaterials with tissue, as was clearly observed over the years, induces immune reactions in a material and patient specific manner, where both surface and bulk properties of scaffolds, together with their 3D architecture, have a significant influence on the outcome. This review presents an overview of the reactions to the biomaterials with a specific focus on clinical complications with the implants in the context of immune reactions and an overview of the studies involving biomaterial properties and interactions with innate immune system cells. We emphasize the impact of these studies on scaffold selection and upscaling of microenvironments created by biomaterials from 2D to 3D using immune cell encapsulation, seeding in a 3D scaffold and co-culture with relevant tissue cells. 3D microenvironments are covered with a specific focus on innate cells since a large proportion of these studies used innate immune cells. Finally, the recent studies on the incorporation of adaptive immune cells in immunomodulatory systems are covered in this review. Biomaterial-immune cell interactions are a critical part of regenerative medicine applications. Current efforts in establishing the ground rules for such interactions following implantation can control immune response during all phases of inflammation. Thus, in the near future for complete functional recovery, tissue engineering and control over biomaterials must be considered at the first step of immune modulation and this review covers these interactions, which have remained elusive up to now.

Insights into the toxicity of biomaterials microparticles with a combination of cellular and oxidative biomarkers

Considering that the extensive biomedical, pharmaceutics, cosmetic and other industrial applications of biomaterials (BMs) is of great concern nowadays, regarding their environmental risk, the present study aimed to investigate the effects of four BMs, poly(ε-caprolactone) (PCL), poly(butylene succinate) (PBSu), chitosan (CS) and modified chitosan (succinic acid grafted chitosan) (CS-Suc) in the form of microplastics (particle sizes less than 1 mm) on biochemical parameters of snails Cornu aspersum hemocytes. Due to the absence of knowledge about the environmentally relevant concentrations of BMs, snails were initially treated through their food with a wide range of nominal concentrations of each BM to define the half maximal effective concentration (NRRT₅₀), according to the destabilization degree of hemocytes' lysosomal membranes (by mean of neutral red retention time/NRRT assay). Thereafter, snails were treated with each BM, at concentrations lower than the estimated NRRT₅₀ values in all cases, for periods up to 15 days. After the end of the exposure period, a battery of stress indices were measured in hemocytes of challenged snails. According to the results, all parameters tested in BMs-treated snails statistically differed from those measured in BMs-free snails, thus indicating the pro-oxidant potential of BMs, as well as their ability to affect animals' physiology. The most considerable effect in most cases seems to be caused by modified chitosan and PCL, while chitosan appears to be the least toxic. A common response mechanism of snails' blood cells against the 4 BMs used in the present study was shown. After exposure to each of the studied BMs a significant augmentation in protein carbonyls, MDA equivalents and DNA damage, while a significant reduction in NRRT values was determined in the snails hemocytes, in relation to the unexposed animals. From the biochemical parameters examined, MDA equivalents and DNA damage seem to be more susceptible than the other parameters studied, to respond to BMs effect, with MDA to react with more sensitivity to PCL and CS, while DNA damage to CS-Suc and PBSu. Our results could suggest the simultaneous use of the latter biomarkers in biomonitoring studies of terrestrial ecosystems against the specific BMs.

Anti-inflammatory coating of hernia repair meshes: a 5-rabbit study

PURPOSE

Polymeric mesh implantation has become the golden standard in hernia repair, which nowadays is one of the most frequently performed surgeries in the world. However, many biocompatibility issues remain to be a concern for hernioplasty, with chronic pain being the most notable post-operative complication. Oxidative stress appears to be a major factor in the development of those complications. Lack of material inertness in vivo and oxidative environment formed by inflammatory cells result in both mesh deterioration and slowed healing process. In a pilot in vivo study, we prepared and characterized polypropylene hernia meshes with vitamin E (α-tocopherol)-a potent antioxidant. The results of that study supported the use of vitamin E as potential coating to alleviate post-surgical inflammation, but the pilot nature of the study yielded limited statistical data. The purpose of this study was to verify the observed trend of the pilot study statistically.

METHODS

In this work, we conducted a 5-animal experiment where we have implanted vitamin E-coated and uncoated control meshes into the abdominal walls of rabbits. Histology of the mesh-adjacent tissues and electron microscopy of the explanted mesh surface were conducted to characterize host tissue response to the implanted meshes.

RESULTS

As expected, modified meshes exhibited reduced foreign body reaction, as evidenced by histological scores for fatty infiltrates, macrophages, neovascularization, and collagen organization, as well as by the surface deterioration of the meshes.

CONCLUSION

In conclusion, results indicate that vitamin E coating reduces inflammatory response following hernioplasty and protects mesh material from oxidative deterioration.

Autoimmune/inflammatory syndrome induced by adjuvants-ASIA-related to biomaterials: analysis of 45 cases and comprehensive review of the literature

Systemic autoimmune or granulomatous disorders related to biomaterials of human use have rarely been described. The aim of this study was to report cases of autoimmune/inflammatory syndrome induced by adjuvants (ASIA) related to biomaterial injections and prostheses, mainly silicone, hyaluronic acid, acrylamides and methacrylate compounds in a Spanish patient cohort. This study is a retrospective analysis of clinical, laboratory, histopathological and follow-up data of 45 cases of patients suffering from late-onset, non-infectious inflammatory/autoimmune disorders related to bioimplants. Late onset was defined as 3 months or more post injection. Data were obtained through a further non-systematic but comprehensive review of the literature. Forty-five cases of late-onset adverse reactions related to biomaterial injections or prostheses were reviewed. All cases had systemic complaints that could be categorised as ASIA. In all but four patients, inflammatory features at the implantation site preceded distant or systemic manifestations. Abnormal blood tests were common. Localised inflammatory nodules and panniculitis in 40/45 (88.88%) evolved into a variety of disorders, viz., primary biliary cirrhosis, Sjögren's syndrome, sarcoidosis, human adjuvant disease, vasculitis, inflammatory bowel syndrome and inflammatory polyradiculopathy. Five (11.11%) cases presented primarily with systemic autoimmune disorders. Biomaterials and prostheses can provoke late-onset systemic autoimmune disorders fulfilling ASIA criteria, or present primarily local/regional inflammatory reactions that may eventually evolve into systemic autoimmune and/or granulomatous disorders which fall under ASIA.

A 10-point plan for avoiding hyaluronic acid dermal filler-related complications during facial aesthetic procedures and algorithms for management

The recent rapid growth in dermal filler use, in conjunction with inadequate product and injector control, has heralded a concerning increase in filler complications. The 10-point plan has been developed to minimize complications through careful preconsideration of causative factors, categorized as patient, product, and procedure related. Patient-related factors include history, which involves a preprocedural consultation with careful elucidation of skin conditions, systemic disease, medications, and previous cosmetic procedures. Other exclusion criteria include autoimmune diseases and multiple allergies. The temporal proximity of dental or routine medical procedures is discouraged. Insightful patient assessment, with the consideration of ethnicity, gender, and generational needs, is of paramount importance. Specified informed consent is vital due to the concerning increase in vascular complications, which carry the risk for skin compromise and loss of vision. Informed consent should be signed for both adverse events and their treatment. Product-related factors include reversibility, which is a powerful advantage when using hyaluronic acid (HA) products. Complications from nonreversible or minimally degradable products, especially when layered over vital structures, are more difficult to control. Product characteristics such as HA concentration and proprietary cross-linking should be understood in the context of ideal depth, placement, and expected duration. Product layering over late or minimally degradable fillers is discouraged, while layering of HA of over the same brand, or even across brands, seems to be feasible. Procedural factors such as photographic documentation, procedural planning, aseptic technique, and anatomical and technical knowledge are of pivotal importance. A final section is dedicated to algorithms and protocols for the management and treatment of complications such as hypersensitivity, vascular events, infection, and late-onset nodules. The 10-point plan is a systematic, effective strategy aimed at reducing the risk of dermal filler complications.

Late-Onset Inflammatory Response to Hyaluronic Acid Dermal Fillers

Objective:

Even though injectable hyaluronic acid (HA)–based fillers are considered safe, rare complications, such as late-onset inflammatory reactions have been reported. Possible causes and effective treatments have not been formally described, so this work aims to discuss these and offer a formal protocol for treatment.

Methods:

This article presents 5 clinical cases of late-onset inflammatory response occurring at least 3 months after uneventful injection of HA dermal filler.

Results:

Inflammation appeared spontaneously, usually 4–5 months after the last injection, but in 1 patient, almost 14 months later. One patient was injected at the same time with fillers manufactured by 2 different technologies. In this case, all areas treated with the same filler showed diffuse swelling of inflammatory nature, whereas the lips, treated with the second filler brand, remained unaffected. Four patients reported a flu-like illness or gastrointestinal upset a few days before the onset of dermal filler inflammation.

Conclusion:

Late-onset inflammatory reactions to HA fillers may be self-limiting but are easily and rapidly treatable with oral steroids, and with hyaluronidase in the case of lumps. It is likely these reactions are due to a Type IV delayed hypersensitivity response. Delayed inflammation associated with HA fillers is nonbrand specific. However, the case where 2 different brands were injected during the same session, but only 1 brand triggered a hypersensitivity reaction, suggests that the technology used in the manufacturing process, and the subsequent differing products of degradation, may have an influence on potential allergic reactions to HA fillers.

Anti-inflammatory coatings of hernia repair meshes: A pilot study

The current prevalence of postoperative chronic pain from hernioplasty procedures employing polymer mesh is close to 30%. Most of the researchers agree that oxidative stress, resulting from the release of oxidants and enzymes during acute inflammatory response, is a key factor in the development of posthernioplasty complications. This results in both the decrease of the biomechanical properties and stiffening of the polymer fibers of the mesh, leading to chronic pain. Moreover, enhanced activity of inflammatory cells can lead to an excessive deposition of connective tissue around the implant. In this study polypropylene hernia repair meshes coated with vitamin E (α-tocopherol), a known antioxidant, were prepared and characterized. The absorption isotherm of vitamin E on the mesh was characterized and a release profile study yielded a promising results, showing sustained release of the drug over a 10-day period. An animal study was conducted, and histological analysis five weeks after implantation exhibited a reduced host tissue response for a modified mesh as compared to a plain mesh, as evidenced by a higher mature collagen to immature collagen ratio, as well as lower level of fatty infiltrates, neovascularization and fibrosis in the case of modified mesh. These results support the use of α-tocopherol as a potential coating in attempt to reduce the extent of postoperative inflammation, and thereby improve long-term outcomes of hernioplasty. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 589-597, 2018.

Intravascular large B-cell lymphoma associated with silicone breast implant, HLA-DRB1*11:01, and HLA-DQB1*03:01 manifesting as macrophage activation syndrome and with severe neurological symptoms: a case report

BACKGROUND

Silicone implants have been successfully used for breast augmentation and reconstruction in millions of women worldwide. The reaction to the silicone implant is highly variable; it can lead to local inflammatory symptoms, and sometimes to systemic symptoms and disease. Over 80 cases of anaplastic lymphoma kinase-negative anaplastic large cell lymphoma have been reported in patients with silicone breast implants and have been accepted as a new clinical entity. To the best of our knowledge, an intravascular large B-cell lymphoma associated with a silicone breast implant has not been reported previously.

CASE PRESENTATION

A 48-year-old Caucasian woman who presented with high fever was found to have splenomegaly on physical examination. A laboratory diagnosis revealed pancytopenia, hypertriglyceridemia, and hyperferritinemia. She developed signs of altered sensorium, hemiparesis, aphasia, and cauda equina syndrome. On further evaluation, she fulfilled the necessary five out of eight criteria for diagnosis of macrophage activation syndrome/hemophagocytic lymphohistiocytosis. Dexamethasone administration was followed by prompt improvement; however, 3 days later she again manifested high fever, which persisted despite administration of immunoglobulin and cyclosporine A. Her silicone breast implant was considered a possible contributor to her macrophage activation syndrome and was therefore removed. A histological examination of the capsule tissue showed an extensive lymphohistiocytic/giant cell foreign body reaction suggestive of autoimmune/inflammatory syndrome induced by adjuvants. However, the histological examination unexpectedly also revealed an intravascular large B-cell lymphoma.

CONCLUSIONS

The genetic background of our patient with silicone breast implants might have predisposed her to three rare and difficult to diagnose syndromes/diseases: macrophage activation syndrome/hemophagocytic lymphohistiocytosis, autoimmune/inflammatory syndrome induced by adjuvants, and intravascular large B-cell lymphoma. The simultaneous manifestation of all three syndromes suggests causal interrelationships. Human leukocyte antigen testing in all women who undergo silicon breast implantation could in the future enable us to better evaluate the risk of potential side effects.

Granulomatous foreign-body reactions to permanent fillers: detection of CD123+ plasmacytoid dendritic cells

BACKGROUND

Soft-tissue augmentation with permanent fillers can lead to severe granulomatous foreign-body reactions (GFBRs), but the immune pathomechanism of this complication is still unknown. We performed conventional histologic examination and immunostaining for plasmacytoid dendritic cells (pDCs) in skin sections from patients with GFBR to 4 permanent filler agents, which have been widely used in recent decades.

METHODS

Twenty-one skin biopsies were studied from 19 patients with GFBR to polyalkylimide 4% gel (PAIG, n = 10), polyacrylamide 2.5% gel (PAAG, n = 2), hydroxyethyl methacrylate/ethyl methacrylate in hyaluronic acid (HEMA/EMA, n = 4), or liquid injectable silicone (n = 5). GFBRs were analyzed in hematoxylin and eosin stained sections and pDCs detected using CD123 antibodies. Anti-CD11c immunostaining was performed for comparison.

RESULTS

Grading of the inflammatory infiltrates observed histologically did not correlate with the clinical features of inflammation. Immunostaining for CD123 did not detect pDCs in 8 of 10 polyalkylimide gel, 1 of 2 polyacrylamide gel, and the 5 liquid injectable silicone biopsies. In contrast, all 4 HEMA/EMA biopsies contained collections of pDCs in lymphocytic infiltrates close to filler particles and adjacent sarcoidal granulomas.

CONCLUSIONS

Our data suggest that pDCs contribute to the sarcoidal granulomas associated with injected HEMA/EMA. Recruited pDCs may exert their pro-inflammatory effects by the release of interferon-α at the site of these filler deposits.

Patient factors influencing dermal filler complications: prevention, assessment, and treatment

While rare, complications do occur with the esthetic use of dermal fillers. Careful attention to patient factors and technique can do much to avoid these complications, and a well-informed practitioner can mitigate problems when they do occur. Since cosmetic surgery is usually an elective process, requested by the patient, clinical trials are complex to organize and run. For this reason, an international group of practicing physicians in the field of esthetics came together to share knowledge and to try and produce some informed guidance for their colleagues, considering the literature and also pooling their own extensive clinical experience. This manuscript aims to summarize the crucial aspects of patient selection, including absolute contraindications as well as situations that warrant caution, and also covers important considerations for the pre- and posttreatment periods as well as during the procedure itself. Guidance is given on both immediate and long-term management of adverse reactions. The majority of complications are related to accepting patients inappropriate for treatment or issues of sterility, placement, volume, and injection technique. It is clear that esthetic practitioners need an in-depth knowledge of all aspects of treatment with dermal fillers to achieve optimal outcomes for their patients.

No efficacy for silicone gel sheeting in prevention of abnormal scar formation in children with cancer: a randomized controlled trial

BACKGROUND

Placement of a totally implantable venous access device in children with cancer often leads to hypertrophic scars after its removal. This study investigates whether the use of silicone gel sheets has a beneficial effect on scar outcome in children with cancer.

METHODS

In a three-arm randomized controlled trial, the effects of use of silicone gel sheets for 2 and 6 months were assessed and compared with no intervention in children with cancer after removal of the totally implantable venous access device. Silicone gel sheets were first administered 14 days after surgery. The 1-year follow-up included measurements at seven time points. Next to scar size assessment, the modified Vancouver Scar Scale was used to assess scar outcome.

RESULTS

Thirty-six children participated. For hypertrophy, no significant differences were found between the two intervention groups and the control group. However, at 1-year follow-up, the 2-month application group showed significantly smaller scars compared with the group receiving silicone gel sheet treatment for 6 months (p = 0.04), but not when compared with the control group (p = 0.22). Longitudinal multilevel analyses could not confirm these findings and showed no significant intervention effects on both outcomes.

CONCLUSIONS

This study provides no strong evidence to support the use of silicone gel sheets after totally implantable venous access device removal in children with cancer. There seems to be a small benefit for scar width with application for 2 months. However, for hypertrophy, the scar outcome shows no significant difference between the control group and the 2-month and 6-month treatment groups.

Dermal fillers: facts and controversies

Dermal fillers have been used for decades in soft tissue augmentation. Currently, filler implementation is among the most common minimally invasive procedures for rejuvenation and body sculpturing. There is a broad variety of filler materials and products. Despite immense experience, a number of controversies in this topic exist. Some of these controversies are addressed in this review, for example, who should perform filler injections, the difference between permanent and nonpermanent fillers, the off-label use of liquid silicone, and the role of pain reduction. Implementation of guidelines and restriction of filler use by trained physicians can improve safety for patients.

Bone Marrow Protein Oxidation in Response to Ionizing Radiation in C57BL/6J Mice

The bone marrow is one of the most radio-sensitive tissues. Accidental ionizing radiation exposure can damage mature blood cells and hematopoietic progenitor/stem cells, and mortality can result from hematopoietic insufficiency and infection. Ionizing radiation induces alterations in gene and protein expression in hematopoietic tissue. Here we investigated radiation effects on protein carbonylation, a primary marker for protein oxidative damage. C57BL/6 mice were either sham irradiated or exposed to 7.5 Gy ⁶⁰Co (0.6 Gy/min) total body irradiation. Bone marrow was obtained 24 h post-irradiation. Two dimensional (2-D) gel electrophoresis and Oxyblot immunodetection were used to discover carbonylated proteins, and peptide mass fingerprinting was performed for identification. 2D gels allowed the detection of 13 carbonylated proteins in the bone marrow; seven of these were identified, with two pairs of the same protein. Baseline levels of carbonylation were found in 78 kDa glucose-related protein, heat shock protein cognate 71 KDa, actin, chitinase-like protein 3 (CHI3L1), and carbonic anhydrase 2 (CAII). Radiation increased carbonylation in four proteins, including CHI3L1 and CAII, and induced carbonylation of one additional protein (not identified). Our findings indicate that the profile of specific protein carbonylation in bone marrow is substantially altered by ionizing radiation. Accordingly, protein oxidation may be a mechanism for reduced cell viability.

Late-onset inflammatory adverse reactions related to soft tissue filler injections

An ever-increasing number of persons seek medical solutions to improve the appearance of their aging skin or for aesthetic and cosmetic indications in diverse pathological conditions, such as malformations, trauma, cancer, and orthopedic, urological, or ophthalmological conditions. Currently, physicians have many different types of dermal and subdermal fillers, such as non-permanent, permanent, reversible, or non-reversible materials. Despite the claims of manufacturers and different authors that fillers are non-toxic and non-immunogenic or that complications are very uncommon, unwanted side effects do occur with all compounds used. Implanted, injected, and blood-contact biomaterials trigger a wide variety of adverse reactions, including inflammation, thrombosis, and excessive fibrosis. Usually, these adverse reactions are associated with the accumulation of large numbers of mononuclear cells. The adverse reactions related to fillers comprise a broad range of manifestations, which may appear early or late and range from local to systemic. Clinicians should be aware of them since the patient often denies the antecedent of injection or is unaware of the material employed. Most of these adverse effects seem to have an immunological basis, the fillers acting more as adjuvants than as direct T-cell activators, on a background of genetic predisposition. Their treatment has not been the subject of well-designed studies; management of both acute and systemic reactions is often difficult, and requires anti-inflammatory and occasionally immunosuppressive therapy. The clinical, pathological, and therapeutic aspects of inflammatory and immune-mediated late-onset adverse reactions related to soft tissue filler injections are thoroughly reviewed herein.

Autoimmune/inflammatory syndrome (ASIA) induced by biomaterials injection other than silicone medical grade

BACKGROUND

Systemic autoimmune/granulomatous adverse reactions related to biomaterials other than silicone have rarely been reported.

AIM

The aim of this paper is to communicate the cases of autoimmune/inflammatory syndrome induced by adjuvants (ASIA) in a study of Spanish patients suffering from inflammatory disorders related to biomaterial injections other than silicone, principally hyaluronic acid, acrylamides or methacrylate compounds.

METHODS

The authors performed a retrospective analysis of the clinical, laboratory, histopathology and follow-up of a cohort of 250 cases of patients suffering from inflammatory/autoimmune disorders related to bioimplant injections.

RESULTS

Of these 250 cases, patients with adverse reactions related to silicone injections (n = 65) were excluded. Of the remaining 185, 15 cases (8%) had systemic or distant and multiple complaints that could be categorized as ASIA. In all but four patients, inflammatory features at the implantation site preceded distant or systemic manifestations. Abnormal blood tests were common. Eleven cases (73.3%) with inflammatory localized nodules and panniculitis evolved into a variety of disorders, namely, primary biliary cirrhosis, Sjögren's syndrome, sarcoidosis, human adjuvant disease and inflammatory polyradiculopathy. Four cases presented primarily with systemic autoimmune disorders.

CONCLUSIONS

Infrequently, biomaterials other than silicone can provoke local inflammatory adverse reactions that may evolve into systemic autoimmune and/or granulomatous disorders. Whether or not these biomaterials act as an adjuvant, they could be included in the ASIA category.

Probable biofilm formation in the cheek as a complication of soft tissue filler resulting from improper endodontic treatment of tooth 16

Injectable filling agents offer the promise of a better appearance without surgery and, among them, hyaluronic acid is the most commonly used. Although complications are rare, it is necessary to know the possible side effects and complications in order to be prepared for their management. That is why many researchers have been focusing on the interactions between hyaluronic acid and pathogens, inflammatory mediators, the immune system, and markers of oxidative stress to achieve efficient drug delivery, given that hyaluronic acid has widening applications in the field of nanomedicine. Here we report the case of a 37-year-old female patient who returned to our clinic with an abscess in her left cheek 3 months after a deep injection of 1 mL of stabilized hyaluronic acid in both cheeks. Steroid and antibiotic therapy was initiated without success, and abscess drainage was performed. Extraction of tooth 16 was performed 11 days after insertion of drains into the abscess. Laboratory blood tests showed acute inflammation of presumed bacterial etiology. Microbiological examination of pus was negative. Bacterial cultures were found in the extracted tooth. After antibiotic therapy, a complete reversal of the pathological process was observed. The present report highlights the need to assess periodontal problems prior to any aesthetic facial treatment. Analyses of further case reports and clinical studies are necessary to understand the potential role of hyaluronic acid in the formation of biofilm, and how to avoid this complication, thereby increasing the safety of hyaluronic acid-based procedures.