Skin Testing and Drug Provocation Tests in Epidermal Necrolysis: A French Experience.

BACKGROUND: There are limited data on the use of skin testing, other than patch testing, and challenges in the evaluation of epidermal necrolysis (EN), including Stevens-Johnson syndrome and toxic epidermal necrolysis. OBJECTIVE: To report a French multicenter experience in skin testing and challenges in EN, and investigate the factors associated with tests' positivity. METHODS: All patients who were evaluated by patch tests (PTs), skin prick tests, intradermal tests (IDTs), or drug provocation tests (DPTs) for EN between 2010 and 2020 were retrospectively included through 2 French drug reaction networks. RESULTS: In total, 113 patients were included from 8 centers. Median (interquartile range) time from EN to hypersensitivity workup was 7.9 months (5.1-15 months). All patients had PTs, 17 (15%) had skin prick tests or IDTs with delayed readings and 32 (28.3%) had DPTs. One mild reaction occurred after a DPT. Overall, 22 patients (19.5%) had positive PTs, and the only factors associated with positivity were Algorithm of Drug Causality for Epidermal Necrolysis (ALDEN) score and drug class. Only 1 IDT was positive but considered irrelevant. The DPTs were never performed to prove responsibility of a highly suspected drug but were used to confirm current tolerance of needed medications. CONCLUSIONS: Allergological workup in EN, performed by specialists involved in EN, seems safe. Skin tests, although of limited sensitivity, can be helpful for considering the reintroduction of essential drugs according to a benefit-to-risk decision. We propose an algorithm for approaching hypersensitivity testing in patients with EN, to be adapted to each patient.

Bone Status According to Neurofibromatosis Type 1 Phenotype: A Descriptive Study of 60 Women in France.

There is an increased risk of osteoporosis and an abnormal bone turn over in neurofibromatosis 1 (NF1). Our objective is to evaluate bone status in NF1 and to look for associations with cutaneous phenotype. We conducted a descriptive, monocentric study. We included 60 NF1 women, 18-51 years old, non-menopausal, divided in 2 groups: «at risk phenotype¼ (ARP) composed by 30 patients with at least 2 subcutaneous neurofibromas (SC-NF) and «classical phenotype¼ (CP) composed by 30 patients with none or 1 SC-NF. We evaluated low bone mineral density (BMD) risk factors and measured BMD, calcium and phosphorus homeostasis and bone turnover markers. Before 50 years old, Z-score has to be used to assess BMD. Z-score < - 2 is below expected range and represents 2.5% of the population. There was no difference between the two groups. Overall, Z-scores were low and 5 patients had a Z-score < - 2 (8.3%), which is 3 times general population low BMD frequency. 10 fragility fractures occurred in 8 patients, among which 2 were vertebral fractures. 85% had low calcium intake. 12 patients had hypophosphoremia, 25 elevated PTH. Vitamin D levels were low for 86.4%. 41 patients (69.5%) had at least one abnormal bone turnover markers. Low BMD is 3.3 times more frequent in NF1 than in general population, with high fracture risk, regardless of the skin phenotype, classical or at risk, because of high bone turn over and secondary hyperparathyroidism due to vitamin D deficiency and poor calcium intake.

Neurofibromatosis 1 French national guidelines based on an extensive literature review since 1966.

Neurofibromatosis type 1 is a relatively common genetic disease, with a prevalence ranging between 1/3000 and 1/6000 people worldwide. The disease affects multiple systems with cutaneous, neurologic, and orthopedic as major manifestations which lead to significant morbidity or mortality. Indeed, NF1 patients are at an increased risk of malignancy and have a life expectancy about 10-15 years shorter than the general population. The mainstay of management of NF1 is a patient-centered longitudinal care with age-specific monitoring of clinical manifestations, aiming at the early recognition and symptomatic treatment of complications as they occur. Protocole national de diagnostic et de soins (PNDS) are mandatory French clinical practice guidelines for rare diseases required by the French national plan for rare diseases. Their purpose is to provide health care professionals with guidance regarding the optimal diagnostic and therapeutic management of patients affected with a rare disease; and thus, harmonizing their management nationwide. PNDS are usually developed through a critical literature review and a multidisciplinary expert consensus. The purpose of this article is to present the French guidelines on NF1, making them even more available to the international medical community. We further dwelled on the emerging new evidence that might have therapeutic potential or a strong impact on NF1 management in the coming feature. Given the complexity of the disease, the management of children and adults with NF1 entails the full complement healthcare providers and communication among the various specialties.

Higher Frequency of Dipeptidyl Peptidase-4 Inhibitor Intake in Bullous Pemphigoid Patients than in the French General Population.

Dipeptidyl peptidase-4 inhibitors have been suspected to induce bullous pemphigoid (BP). The objective of this study was to compare the observed frequency of gliptin intake in a large sample of 1,787 BP patients diagnosed between 2012 and 2015 in France, with the expected frequency after indirect age standardization on 225,412 individuals extracted from the database of the National Healthcare Insurance Agency. The secondary objective was to assess the clinical characteristics and the course of gliptin-associated BP, depending on whether gliptin was continued or stopped. The observed frequencies of intake of the whole gliptin class and that of vildagliptin in the BP population were higher than those in the general population after age standardization (whole gliptin class: 6.0%; 95% confidence interval = 4.9-7.1% vs. 3.6%, observed-to-expected drug intake ratio = 1.7; 95% confidence interval = 1.4-2.0; P < 0.0001; vildagliptin = 3.3%; 95% confidence interval = 2.5-4.1% vs. 0.7%, ratio = 4.4; 95% confidence interval = 3.5-5.7; P < 0.0001). The association of any gliptin+metformin was also higher than in the general population, ratio = 1.8 (95% confidence interval = 1.3-2.4; P < 0.0001). Gliptin-associated BP had no specific clinical characteristics. Gliptin was stopped in 48 (45.3%) cases. Median duration to achieve disease control, rate, and delay of relapse were not different whether gliptin was stopped or continued. This study strongly supports the association between gliptin intake, particularly vildagliptin, and the onset of BP.

Patch testing in non-immediate cutaneous adverse drug reactions: value of extemporaneous patch tests.

BACKGROUND: Patch testing following a standardized protocol is reliable for identifying the culprit drug in cutaneous adverse drug reactions (CADRs). However, these patch tests (PTs) require pharmaceutical material and staff, which are not always easily available. OBJECTIVES: To evaluate an extemporaneous PT method in CADRs. METHODS: We retrospectively analysed data for all patients referred to our department between March 2009 and June 2013 for patch testing after a non-immediate CADR. The patients who supplied their own suspected drugs were tested both with extemporaneous PTs and with conventional PTs. Extemporaneous PTs involved a nurse crushing and diluting the drug in pet. in a ratio of approximately one-third to two-thirds. Standardized PTs were performed according to guidelines, with commercial drugs diluted to 30% or with active ingredients diluted to 10%. We analysed the data for the two PT methods in terms of the number of positive test reactions, drugs tested, and type of CADR for patients in whom the two PT methods were used. RESULTS: In total, 75 of 156 patients underwent the two PT procedures, including 91 double tests. Overall, 21 tests gave positive reactions with the two methods, and 69 other tests gave negative results with the two methods. CONCLUSION: Our series yielded results similar to those of published series concerning the types of CADR and the drugs responsible. Our results suggest that, for CADRs, if a patient supplies a suspected drug but if the pharmaceutical material and staff are not available for conventional PTs, extemporaneous PTs performed by the nurse with the commercial drug used by the patient can be useful and reliable.

Severe cutaneous adverse reactions to drugs.

During the past decade, major advances have been made in the accurate diagnosis of severe cutaneous adverse reactions (SCARs) to drugs, management of their manifestations, and identification of their pathogenetic mechanisms and at-risk populations. Early recognition and diagnosis of SCARs are key in the identification of culprit drugs. SCARS are potentially life threatening, and associated with various clinical patterns and morbidity during the acute stage of Stevens-Johnson syndrome and toxic epidermal necrolysis, drug reactions with eosinophilia and systemic symptoms, and acute generalised exanthematous pustulosis. Early drug withdrawal is mandatory in all SCARs. Physicians' knowledge is essential to the improvement of diagnosis and management, and in the limitation and prevention of long-term sequelae. This Seminar provides the tools to help physicians in their clinical approach and investigations of SCARs.

Acute Liver Failure/Injury Related to Drug Reaction With Eosinophilia and Systemic Symptoms: Outcomes and Prognostic Factors.

BACKGROUND: Drug reaction with eosinophilia and systemic symptoms (DRESS) is a rare severe adverse drug-induced reaction with multiorgan involvement. The outcome and prediction of those patients who develop severe acute liver injury (sALI) or acute liver failure (ALF) remain little known. METHODS: A multicenter retrospective study of patients admitted with a diagnosis of DRESS-related sALI or ALF. Histological review was performed on liver core biopsies from native livers. RESULTS: Sixteen patients (11 women, 5 men; mean age, 39±17.2 years) were classified as having definite (n=13) or probable (n=3) DRESS. At admission, 3 patients had hepatic encephalopathy; median levels of prothrombin time, INR, and total bilirubin were, respectively, 33% (Q1-Q3, 21-41), 2.74 (1.98-4.50), and 94 µmol/L (Q1-Q3, 39.5-243.5). Nine patients received corticosteroid therapy. Overall, 9 patients improved spontaneously and 7 worsened (liver transplantation [LT] (n=5), deceased (n=2)). Transplantation-free and post-LT survival was 56% and 60%, respectively. After LT, DRESS recurrence was observed in 3 of 5 patients. Systemic corticosteroid therapy was not significantly associated with a clinical improvement. In the multivariate analysis, factor V level less than 40% at day 0 and factor V levels of 40% or greater at admission but decreasing at day 2 were associated with worse outcome. Pathological findings (n=7) revealed atypical lymphoid infiltrates, Kupffer cell hyperplasia with erythrophagocytosis, and an inconstant presence of eosinophils. CONCLUSIONS: The spontaneous prognosis of patients with sALI/ALF due to DRESS is poor and was not improved by corticosteroid therapy. Histology is helpful to establish diagnosis. Dynamic variables regarding factor V values are predictive of a poor outcome.

Ischemic myopathy revealing systemic calciphylaxis.

INTRODUCTION: Patients with renal failure who are being treated with dialysis frequently develop neuromuscular manifestations. Renal failure-associated calciphylaxis, also termed calcific uremic arteriolopathy (CUA), is a life-threatening condition usually observed in patients with end-stage renal disease on chronic dialysis or after renal transplantation. METHODS: We describe a hemodialyzed patient who presented with rapidly progressive unexplained systemic vasculopathy, muscle atrophy, and proximal weakness, that unexpectedly proved to be caused by calciphylaxis. RESULTS: Quadriceps muscle biopsy disclosed diffuse vascular calcific deposits on medium- and small-sized vessels, characteristic of CUA. Other changes included ischemic myopathy, focal intracellular calcium accumulation within myofibers, and calcium deposits in endomysial capillaries associated with marked complement activation and C5b9 formation. CONCLUSION: There are only a few descriptions of muscle involvement in the context of CUA, a condition with a prognosis that depends on early diagnosis and treatment. This report underscores the usefulness of muscle biopsy in the diagnosis of systemic calciphylaxis. Muscle Nerve 56: 529-533, 2017.

Interleukin-15 Is Associated with Severity and Mortality in Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis.

Early diagnosis and prognosis monitoring for Stevens-Johnson syndrome/toxic epidermal necrolysis (TEN) still remain a challenge. This study aims to explore any cytokine/chemokine with prognostic potential in Stevens-Johnson syndrome/TEN. Through screening a panel of 28 serological factors, IL-6, IL-8, IL-15, tumor necrosis factor-α, and granulysin were upregulated in patients with Stevens-Johnson syndrome/TEN and selected for the further validation in total 155 patients with Stevens-Johnson syndrome/TEN, including 77 from Taiwan and 78 from the Registry of Severe Cutaneous Adverse Reactions. Among these factors evaluated, the levels of IL-15 (r = 0.401; P < 0.001) and granulysin (r = 0.223; P = 0.026) were significantly correlated with the disease severity in 112 samples after excluding patients with insufficient data to calculate the score of TEN. In addition, IL-15 was also associated with mortality (P = 0.002; odds ratio, 1.09; 95% confidence interval, 1.03-1.14; P = 0.001; adjusted odds ratio, 1.10; 95% confidence interval, 1.04-1.16). Consistent results were obtained after the exclusion of Taiwanese patients with sepsis to rule out possible confounders. Moreover, IL-15 was shown to enhance cytotoxicity of cultured natural killer cells and blister cells from patients with TEN. Our findings highlight a usefulness of IL-15 in prognosis monitoring and therapeutic intervention of this devastating condition.

AP1S3 Mutations Cause Skin Autoinflammation by Disrupting Keratinocyte Autophagy and Up-Regulating IL-36 Production.

Prominent skin involvement is a defining characteristic of autoinflammatory disorders caused by abnormal IL-1 signaling. However, the pathways and cell types that drive cutaneous autoinflammatory features remain poorly understood. We sought to address this issue by investigating the pathogenesis of pustular psoriasis, a model of autoinflammatory disorders with predominant cutaneous manifestations. We specifically characterized the impact of mutations affecting AP1S3, a disease gene previously identified by our group and validated here in a newly ascertained patient resource. We first showed that AP1S3 expression is distinctively elevated in keratinocytes. Because AP1S3 encodes a protein implicated in autophagosome formation, we next investigated the effects of gene silencing on this pathway. We found that AP1S3 knockout disrupts keratinocyte autophagy, causing abnormal accumulation of p62, an adaptor protein mediating NF-κB activation. We showed that as a consequence, AP1S3-deficient cells up-regulate IL-1 signaling and overexpress IL-36α, a cytokine that is emerging as an important mediator of skin inflammation. These abnormal immune profiles were recapitulated by pharmacological inhibition of autophagy and verified in patient keratinocytes, where they were reversed by IL-36 blockade. These findings show that keratinocytes play a key role in skin autoinflammation and identify autophagy modulation of IL-36 signaling as a therapeutic target.

Low Rates of Blood Transfusion in Elective Resections of Neurofibromas in a Cohort Study: Neurofibroma Length as a Predictor of Transfusion Requirement.

BACKGROUND: Neurofibromas in neurofibromatosis type 1 induce aesthetic and functional morbidity. Perioperative bleeding has been reported as an obstacle to neurofibroma resections. The authors studied the requirement for blood transfusion during surgical treatment of neurofibromatosis type 1. METHODS: Six hundred twenty-two procedures performed on 390 neurofibromatosis type 1 patients at the national referral center from 1995 to 2011 were analyzed in two chronologic sets of patients: set 1 (February of 1995 to September of 2007), in which only one surgeon operated; and set 2 (October of 2007 to January of 2011), in which two additional surgeons were involved. Malignant peripheral nerve sheath tumors, reconstructive procedures, and spontaneous hemorrhages were excluded from the analysis. Age, sex, preoperative hemoglobin concentration, location, length, estimated volume and histologic features of the largest neurofibroma (cumulative values for multiple neurofibromas), and procedure duration were studied as potential predictors of blood transfusion that were measured in terms of units of packed red blood cells. RESULTS: Seventy reconstructive procedures, two cases of spontaneous hemorrhage, and 32 malignant peripheral nerve sheath tumor resections were excluded. Among 516 procedures (318 and 198 in sets 1 and 2, respectively), 17 (2.7 percent) required blood transfusions. The requirement for transfusion was associated with neurofibroma length in both sets, with an optimal cutoff value of 13 cm in both sets. CONCLUSIONS: Contrary to the literature, the requirement for blood transfusion was found to be low (2.7 percent of the cases) during elective resection of neurofibromas in neurofibromatosis type 1. Elective resections of benign neurofibromas less than 13 cm in length were not associated with a requirement for blood transfusion. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Metabolic Tumour Burden Measured by 18F-FDG PET/CT Predicts Malignant Transformation in Patients with Neurofibromatosis Type-1.

BACKGROUND: To investigate the diagnostic and prognostic performances of 18F-FDG PET/CT measures of metabolic tumour burden in patients with neurofibromatosis type-1 (NF1), suspect of malignant transformation. METHODS: This retrospective study included 49 patients (15-60 years old, 30 women) with a diagnosis of NF1, followed in our Reference Centre for Rare Neuromuscular Diseases, who presented clinical signs of tumour progression (pain, neurological deficit, tumour growth). Quantitative metabolic parameters were measured on 149 tumoral targets, using semi-automatic software and the best cut off values to predict transformation was assessed by Receiver Operating Characteristics (ROC) analysis. Prognostic value of PET/CT metabolic parameters was assessed by Kaplan-Meier estimates of overall survival. RESULTS: Lesions were histologically documented in 40 patients: a sarcomatous transformation was found in 16, a dysplastic neurofibroma (NF) in 7, and a benign NF in 17; in the remaining 9 patients, a minimal follow-up of 12 mo (median 59 mo) confirmed the absence of transformation. The optimal cut off values for detection of malignant transformation were, in decreasing order of area under the ROC curves, a tumour-to-liver (T/L) ratio >2.5, SUVmax > 4.5, total lesion glycolysis (TLG) > 377, total metabolic tumour volume (TMTV) > 88 cm3, and heterogeneity index (HIsuv) > 1.69. The best prognostic marker was the TLG: the 4-y estimates of survival were 97% [95% CI, 90% - 100%] in patients with TLG ≤ 377 vs. 27% [95% CI, 5% - 49%] in patients with TLG > 377 (P < 0.0001; χ2 27.85; hazard ratio 13.27 [95% CI, 3.72-47.35]). T/L ratio, SUVmax and TMTV demonstrated slightly lower performance to predict survival, with χ2 ranging 14.41-19.12. The HIsuv index was not predictive of survival. CONCLUSION: Our study demonstrates that TLG and TMTV, as PET/CT measures of metabolic tumour burden, may be used clinically to identify sarcomatous transformation in patients with NF1 and predict overall survival, with a higher specificity for the TLG. Conventional measures such as the SUVmax, and T/L ratio also demonstrate high prognostic value.

Facial Scars following Toxic Epidermal Necrolysis: Role of Adnexal Involvement?

Toxic epidermal necrolysis (TEN) is a severe cutaneous adverse drug reaction leading to extensive sloughing of the skin. Late cutaneous complications such as pigmentation disorders are frequently reported. In this report, we present particular facial cutaneous sequelae with histological analysis after TEN. Two young patients who had survived TEN presented permanent multiple hypopigmented papules on the face affecting their quality of life. Histological analysis revealed areas of scarring, dystrophic microcalcifications and sebaceous hyperplasia. Late cutaneous sequelae are well documented; however, the physiopathological mechanisms leading to different clinical presentations remain unknown. We suggest that the destruction of the hair follicle by necrolysis leads to secondary dermal microcalcifications, scarring and sebaceous hyperplasia. Further studies are needed for a better understanding of these findings.

[DRUG INDUCED EXANTHEMA AND SEVERE CUTANEOUS DRUG REACTIONS]. / Exanthèmes médicamenteux et toxidermies sévères Signes généraux et muqueux imposent l'arrêt immédiat du médicament.

Cutaneous adverse drug reactions (CADR) are delayed hypersensivities. Their clinical presentation and severity are very diverse ranging from the frequent and benign exanthemas to the rare but severe CADR involving deep organs in the case of drug reaction with eosinophilia and systemic symptoms (DRESS) or leading to skin bulla and epidermal detachment in toxic epidermal necrolysis. The main differential diagnoses are infections, especially viral ones, which could give clinical symptoms identical to those occurring in CADR.

Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: An Update.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening mucocutaneous reactions, predominantly drug induced. The mortality rates for SJS and TEN are as high as 30 %, and short- and long-term morbidities are very common. SJS/TEN is one of the few dermatological diseases that constitute a true medical emergency. Early recognition and prompt and appropriate management can be lifesaving. In recent years, our understanding of the pathogenesis, clinical presentation, and management of SJS/TEN has improved. Nevertheless, in 2015, there are still no internationally accepted management guidelines. This review summarizes up-to-date insights on SJS/TEN and describes a protocol for assessment and treatment. We hope these suggested guidelines serve as a practical clinical tool in the management of SJS/TEN. The classic manifestation of SJS/TEN consists of initial "flu-like" symptoms (malaise, fever, anorexia) in the prodromal phase, followed by cutaneous and mucous membrane (ocular, oral, and genital) inflammation and pain, and other systemic involvement. Symptoms usually begin 4-28 days after the onset of drug intake. Treatment is multidisciplinary and includes identification and withdrawal of the culprit drug, transfer to a specialist unit, supportive care, medical treatment, communication, and provision of appropriate information and emotional support.