Search Results (100)

Background/Objectives: Acute generalized exanthematous pustulosis (AGEP) is a severe drug-induced cutaneous reaction characterized by the abrupt onset of sterile pustules, fever, neutrophilia, and a T cell-mediated type IVd hypersensitivity response. This narrative review synthesizes current evidence on pharmacological triggers, immunopathogenic mechanisms, diagnostic criteria, and differential diagnosis to provide a clinically oriented framework. Methods: A comprehensive literature search was conducted in PubMed/MEDLINE, Scopus, ScienceDirect, and SpringerLink for studies published between 2000 and 2025, complemented by selected clinical reference sources. Studies addressing clinical features, immunological pathways, pharmacovigilance signals, and diagnostic tools for AGEP were included. Synthesis of Evidence: β-lactam antibiotics remain the most frequent triggers, while increasing associations have been reported with hydroxychloroquine, targeted therapies, immune checkpoint inhibitors, psychotropic agents, and vaccines. Immunopathogenesis is driven by IL-36 activation, CXCL8/IL-8–mediated neutrophil recruitment, and IL36RN mutations, explaining overlap with pustular psoriasis. Diagnostic accuracy improves through integration of drug latency, clinical morphology, histopathology, biomarkers, and standardized tools such as the EuroSCAR score. Conclusions: AGEP is a complex pustular reaction induced by diverse drugs and amplified by IL-36-mediated inflammation. Accurate diagnosis requires a multidimensional approach supported by structured algorithms and robust pharmacovigilance to identify evolving drug-associated patterns. Full article

Background/Objectives: Cutaneous adverse drug reactions (CADRs) represent the most common manifestations of drug-induced allergy, with most unfavorable clinical outcomes seen in severe cutaneous adverse reactions (SCARs). To manage SCARs immediate cessation of the offending drug is needed; therefore, it is crucial to identify the list of medications associated with SCARs in real-world clinical practice. The objective of this study was to evaluate the structure of drugs associated with SCARs and to analyze drug-induced SCAR signals by calculating the reporting odds ratio (ROR) and proportional reporting ratio (PRR) based on spontaneous reports extracted from the Russian national pharmacovigilance database. Methods: A retrospective, descriptive pharmacoepidemiological analysis of spontaneous reports (SRs) registered in the pharmacovigilance database from 1 April 2019 to 31 March 2025. Results: A total of 7011 SRs with SCARs were finally revealed, with 907 identified drug triggers. The most frequently reported were antibacterial drugs for systemic use (22.8%), antineoplastic agents (17.8%), and antiepileptics (6.0%). The top five drugs involved in SCARs were dupilumab (2.14%, n = 244), piperacillin and beta-lactamase inhibitor (2.0%, n = 227), pembrolizumab (1.98%, n = 225), levofloxacin (1.95%, n = 222), and linagliptin (1.93%, n = 220). The strongest signals were detected for linagliptin (PRR = 15.37, 95% CI: 13.54–17.44; ROR = 17.24, 95% CI: 14.95–19.88), followed by clindamycin (PRR = 12.44, 95% CI: 10.89–14.21; ROR = 13.62, 95% CI: 11.77–15.77) and by piperacillin and beta-lactamase inhibitor (PRR = 10.02, 95% CI: 8.86–11.43; ROR = 10.81, 95% CI: 9.42–12.40). Conclusions: Pharmacovigilance databases facilitate the identification of diverse phenotypes of SCARs and the list of culprit drugs. The accumulated data serve as a valuable tool to enhance clinical practice outcomes and strengthen overall healthcare monitoring. Full article

Background/Objectives: Drug hypersensitivity reactions (DHRs) are an important cause of morbidity in hospitalized patients, but their epidemiology and management in the inpatient setting are not well defined. Mislabeling of drug allergies may lead to inappropriate treatment and reduced antimicrobial stewardship. This study aimed to characterize the clinical profile, diagnostics, and management of inpatients referred for suspected drug allergy in a tertiary care hospital. Methods: We retrospectively reviewed all adult inpatients (≥18 years) at Luigi Sacco Hospital (Milan, Italy) who received allergology consultation between 1 June 2022 and 31 May 2025. Data on demographics, reaction type, culprit drugs, investigations, and management were collected. Immediate reaction severity was graded using the United States Drug Allergy Registry (USDAR) scale; delayed reactions were classified as severe cutaneous adverse reactions (SCARs) or non-SCARs. Logistic regression identified predictors of severity. Results: Among 35,438 admissions, 334 patients (0.9%) were evaluated; median age was 65 years, 51.2% were female, 67.4% had atopic comorbidities, and 55.1% reported prior drug allergy. Immediate reactions occurred in 49.1%, delayed in 43.7%. Cutaneous involvement was present in 86.8%, anaphylaxis in 6.6%, and SCARs in 3.9%. Antibiotics—particularly β-lactams—were most often implicated. In multivariate analysis, antibiotic exposure and older age were linked to more severe immediate reactions, while the absence of atopy predicted SCARs. Desensitization was successfully performed in 16.2% of patients. Conclusions: DHRs in inpatients are frequent and often involve high-risk drugs. Structured inpatient allergology services and an “allergy stewardship” approach may reduce DHR-related risks, support optimal therapy, and improve antimicrobial use strategies in tertiary care settings. Full article

Background: Fixed drug eruption (FDE) is a non-immediate, CD8+ T cell–mediated hypersensitivity reaction characterized by well-demarcated erythematous–violaceous plaques that recur at the same site after re-exposure to the causative drug. Although NSAIDs and antibiotics are the most common triggers, various other medications may induce FDE, and genetic susceptibility has been linked to specific HLA alleles. Methods: We conducted a clinical evaluation supported by patch testing, oral drug provocation, and assessment of therapeutic alternatives to identify the causative agent and confirm delayed-type hypersensitivity. Results: We report the case of a 53-year-old woman with essential hypertension, autoimmune thyroiditis, and renal lithiasis who developed well-demarcated erythematous plaques with central vesiculation and moderate pruritus on the dorsal hand and posterior calf approximately 8 h after ingestion of a 60 mg etoricoxib tablet. Patch testing was negative, while oral challenge confirmed etoricoxib-induced FDE; celecoxib was subsequently evaluated as a potential safe alternative. Conclusions: This case underscores the importance of an integrated diagnostic approach—including careful history, clinical examination, and confirmatory testing—to accurately diagnose delayed cutaneous drug reactions and to identify safe therapeutic options for patients. Full article

A 10-year-old male neutered British Shorthair cat with diabetes mellitus presented with an acute onset of unilateral swelling, erythema, alopecia and coalescing ulcerations of the face and periocular skin. Initial clinical differential diagnoses were trauma, infections (including feline respiratory viruses), arthropod bites, and eosinophilic dermatoses such as eosinophilic granuloma complex, mosquito-bite hypersensitivity and cutaneous adverse drug reaction. Histopathology revealed fulminant furunculosis with abundant eosinophils and vasculitis. Initial topical glucocorticoid treatment partially improved the clinical signs but severely raised serum glucose levels. As a result, systemic glucocorticoids and ciclosporin were not considered optimal treatments, and the off-label and short-term use of oclacitinib was chosen with the owner’s informed consent. This treatment induced fast remission of clinical signs with no recurrence for 17 months. Secondary fusion of the eyelids caused by cicatrization was surgically reconstructed to restore full function. Full article

Lamotrigine is the drug of choice for the treatment of depressive episodes in bipolar disorder (BD). Despite its generally favorable tolerability profile, lamotrigine use is associated with a risk of Cutaneous Adverse Drug Reactions (cADRs), including Stevens–Johnson Syndrome (SJS) and Lyell’s syndrome, also known as toxic epidermal necrolysis (TEN). Genetic markers HLA and, in particular, HLA-B 15:02 and HLA-A 31:01 are crucial in predicting individuals’ susceptibility to developing the symptoms. The symptoms are triggered by type IV hypersensitivity developing because of CTL and NK cell activation, leading to keratinocyte apoptosis, epidermal necrosis and skin detachment. The exact pharmacotherapy that should be widely utilized in treating affected patients has not yet been established. New therapies including JAK inhibitors or cyclosporine show potential in improving outcomes by reducing mortality and enhancing the period of recovery. Key factors in preventing cADRs may include adequate patient observation, gradual titration of the patient’s dose, and reduction of risk factors through screening for HLA polymorphisms. When the initial symptoms of cADR are identified, it is imperative to make an immediate decision to discontinue treatment, as this can significantly reduce the risk of progression to SJS/TEN and systemic complications. The purpose of this review is to identify a significant correlation between lamotrigine use in BD and the occurrence of SJS by showing the risk factors, neuropharmacological mechanisms, immune response and correctness of pharmacotherapy. Full article

Background and Clinical Significance: Intermediate- to high-risk Myelodysplastic Syndrome (MDS), according to the Revised International Prognostic Scoring System (IPSS-M), confers a high risk of progression into acute myeloid leukemia. Treatment with hypomethylating agents, including azacitidine and decitabine, represents the current standard of care. In eligible patients, hypomethylating agents are used as a bridge for allogeneic stem cell transplantation, currently the only curative approach in these malignancies. The most common side effects of hypomethylating agents are myelosuppression, cutaneous injection site reactions (when azacitidine is given subcutaneously), and gastrointestinal symptoms. Uncommon, disabling, and long-lasting side effects represent a threat to effective treatment in this group of patients. Case Presentation: We describe the case of a 49-year-old male patient with IPSS-M intermediate-risk MDS, intended to receive first-line treatment with azacitidine followed by allogeneic stem cell transplantation. The first, late-onset azacitidine reaction was observed 48 h after the first exposure, with cutaneous and respiratory toxicity, followed by the late-onset recurrence of symptoms after azacitidine withdrawal and decitabine introduction. Conclusions: This case highlights atypical, disabling, and long-lasting drug reactions to two hypomethylating agents, with the persistence of hypersensitivity manifestations months after medication withdrawal. Full article

Tuberculosis remains a significant public health challenge globally. The emergence of multidrug-resistant Mycobacterium tuberculosis strains presents one of the biggest hurdles in tuberculosis management. Both first- and second-line tuberculosis drugs are associated with common adverse reactions, which can lead to treatment interruptions and decreased adherence. In this article, we review the most commonly used drugs for the treatment of tuberculosis, focusing on the adverse reactions they may cause. We will examine the frequency and timeline of adverse drug reactions involving gastrointestinal, cardiac, neurological, nephrological, and cutaneous systems. Identifying patients at risk of developing those reactions is crucial for healthcare providers to implement monitoring strategies and manage complications effectively. In the review, we present the data about risk factors, management recommendations, and drug discontinuation rates as a result of side effects. Full article

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by epidermal barrier dysfunction and immune dysregulation, with interleukin (IL)-4, IL-13, and IL-31 recognized as key mediators. Prurigo nodularis (PN) is another chronic inflammatory disorder driven by T helper type 2-mediated inflammation and neural dysregulation, leading to severe pruritus. Nemolizumab, a humanized monoclonal antibody targeting IL-31 receptor A, has been approved for use in the treatment of AD and PN. Clinical trials have demonstrated significant reductions in pruritus and cutaneous symptoms associated with its use. In clinical practice, acute eczema and edematous erythema frequently occur, occasionally necessitating the discontinuation of treatment. Despite these observations, no comprehensive review has examined nemolizumab-associated cutaneous adverse events. This review aimed to examine various cutaneous reactions associated with nemolizumab therapy, including psoriasiform eruptions, AD exacerbation, bullous pemphigoid, drug-induced eruptions, and fungal infections. Potential mechanisms underlying these reactions include T-cell activation due to drug sensitization, immune responses triggered by nemolizumab acting as a hapten, and a relative increase in IL-4 and IL-13 levels following IL-31 inhibition. However, the precise pathophysiological mechanism and risk factors remain unclear, and standardized clinical management guidelines are lacking. Further accumulation of clinical data and immunological research are essential for developing evidence-based strategies to manage these adverse events, ensuring treatment continuity and optimizing patient outcomes. Full article

A 56-year-old female with a history of Luminal A breast cancer, previously treated with surgery, radiotherapy, and systemic therapy, underwent palliative re-irradiation in November 2024 for painful bone metastases. Three weeks later, following the initiation of Fulvestrant, she developed a grade 3 erythematous reaction localized to the re-irradiated area. The reaction persisted with minimal improvement over two months, despite symptomatic management. No infectious or allergic etiologies were identified, and dosimetric analysis confirmed that the delivered radiation dose to the skin was insufficient to directly induce such a reaction. Notably, the erythema was most pronounced along a pre-existing surgical scar, suggesting a localized inflammatory response. Given the temporal relationship with Fulvestrant administration, we hypothesize a drug-induced recall-like phenomenon, though no previous reports have specifically linked Fulvestrant to such an event. This case underscores the need for awareness of unexpected cutaneous reactions following re-irradiation and highlights the potential role of systemic therapies in modulating local tissue responses. Full article

Background: Denosumab, a receptor activator of nuclear factor kappa-Β ligand (RANKL) inhibitor, demonstrates therapeutic effects beyond traditional osteoporosis management through the RANK/RANKL/osteoprotegerin pathway. Methods: This narrative review analyzed 37 studies (2018–2024) examining denosumab’s broader physiological effects and clinical applications. Results: Long-term safety data spanning 10 years showed sustained fracture prevention efficacy with a favorable benefit/risk profile. Compared to bisphosphonates, denosumab demonstrated superior outcomes in bone mineral density improvement and fracture risk reduction, particularly in elderly and frail populations. It enhanced muscular function by improving appendicular lean mass and grip strength while reducing fall risk. The drug showed potential cardiovascular benefits through its effects on cardiac and smooth muscle function. Notably, denosumab use was associated with reduced Type II diabetes mellitus risk through improved glucose metabolism. Additionally, it demonstrated promise in osteoarthritis treatment by suppressing osteoclast activity and chondrocyte apoptosis. While there are multisystem benefits, vigilance is required regarding adverse events, including hypocalcemia, infection risk, cutaneous reactions, and osteonecrosis of the jaw. Conclusions: Denosumab exhibits potential benefits in bone and systemic metabolism. Further research is needed to fully understand its therapeutic potential beyond osteoporosis and optimize clinical applications across different populations. Full article

Background: Drug reaction with eosinophilia and systemic symptoms is a severe cutaneous reaction with a high mortality rate. It is challenging to diagnose due to its similar presentation to infectious disease syndromes, variation with the culprit drug, and lack of awareness. Methods: We searched PubMed, and Embase, for RegiSCAR-scored observational studies, the FDA Adverse Events Reporting System (FAERS) for adverse event reports, and the Allele Frequency Net Database (AFND) for HLA allele frequency. In our meta-analysis, we employed a random effects model to subgroup patients by ethnicity to determine the proportion of DRESS cases compared with various associated medications. Additionally, we identified a correlation between the proportion of cases and the presence of the HLA*A-32:01allele, which is suspected to predispose individuals to DRESS. Results: Twenty-one studies on 1949 DRESS cases in vancomycin and 2558 antimicrobial DRESS reports in the FAERS database were analyzed. Meta-analysis showed a 27% incidence of vancomycin-DRESS, with Caucasians having the highest proportion at 36%. The median latency for symptom onset was 21 days, with no female predisposition. The proportional incidence of vancomycin-DRESS did not correlate with the HLA-A*32:01 allele. The adjusted ROR for vancomycin was 2.40 compared to other antimicrobials, and the risk increased by 77% with concurrent antimicrobials. Piperacillin/tazobactam had a similar DRESS reporting risk at 0.95 (95%CI: 0.88–1.02). Conclusions: Vancomycin significantly contributes to the incidence of DRESS and is more closely related to ethnicity than to allele frequency, indicating that the HLA-A*32:01 allele may not be directly involved. Furthermore, the use of other antimicrobials can influence the reaction, underscoring the need to minimize antimicrobial use for better coverage. Full article

Background: Serious adverse drug reactions (ADRs) can lead to hospital admission and can be fatal, but some of them are preventable. This study aimed to determine the types and frequencies of serious cutaneous ADRs and the methods employed to manage and prevent them, as well as to assess the factors related to their seriousness. Methods: A cross-sectional study was conducted retrospectively on inpatients and outpatients at a tertiary care hospital. All data were collected from the medical records database over a period of 3 years. Serious cutaneous ADRs were identified in the hospital database using the International Classification of Disease and Related Health Problems, 10th Revision (ICD-10). Results: A total of 2151 cases were retrieved using the ICD-10, and 436 patients were randomly selected for this study. Of these, 218 patients experienced ADRs (50.0%). The major clinical symptoms of the eight serious ADRs included anaphylaxis (38.5%) and urticaria (30.2%). The most commonly suspected drug group was antibiotics (45.0%). The main methods of ADR management were drug treatment (84.4%) and drug withdrawal (81.2%). The primary method of ADR prevention was patient drug allergy cards (52.3%). Factors affecting the severity of ADRs were having an underlying condition (p = 0.031) and the concomitant use of drugs (p = 0.044). Conclusions: Anaphylaxis was the most common serious ADR. Patients with underlying diseases and those taking concomitant drugs are more likely to present with serious ADRs. The prevention of serious ADRs should be promoted at all levels in hospitals to reduce harm and prevent their reoccurrence. Full article

Diabetes is a complex global healthcare burden involving multiple organ systems with its prevalence on the rise. SGLT2 inhibitors enhance glucose excretion. The objective of our literature review was to determine the association between cutaneous adverse drug reactions (CADRs) and the use of SGLT2 inhibitors. We collected data on CADRs related to the use of SGLT2 inhibitors from all available published articles and studied their details to understand the patterns of their association. PubMed, Cochrane, Google, and Embase were searched for relevant articles. A total of 37 papers were included and studied. Most articles were case reports followed by pharmacovigilance studies, case series, and reviews. The cutaneous findings ranged from benign eruptions to severe reactions. The available literature suggests a strong link between the use of SGLT2 inhibitors and Fournier’s gangrene/necrotizing fasciitis. T2DM patients using SGLT2 inhibitors have also developed fixed drug eruptions, drug-induced pruritus, and Sweet syndrome/acute febrile neutrophilic dermatosis, among other skin lesions. We found that SGLT2 inhibitors present a risk of developing CADRs. Raising awareness among healthcare providers regarding CADRs to SGLT2 inhibitors can reduce complications, minimize hospitalizations, and improve patient care in the vulnerable population of diabetes patients. Full article

Cutaneous metastases from clear cell renal carcinoma (ccRC) are uncommon and often indicate a poor prognosis. These metastases typically occur on the scalp, face, and trunk, and they can be difficult to diagnose due to their resemblance to benign dermatological tumors. We report the case of a 56-year-old patient with a history of ccRC (TNM stage 4) who was referred to our dermatology department with two rapidly enlarging, painful lesions on the left jawline and scalp, which had developed one month and one week earlier, respectively. On examination, the lesions appeared as well-defined, round to oval plaques with a central ulceration and a peripheral red rim, suggestive of an inflammatory appearance. Dermoscopic examination revealed a structureless pink to orange pattern, atypical central vessels, and irregular linear vessels in a corona-like arrangement. Despite the patient’s stable oncological treatment for six months, pain management had recently included paracetamol, tramadol, and NSAIDs. The primary presumptive diagnosis was of cutaneous metastasis, considering the patient’s history of metastatic ccRC. However, given the recent initiation of new pharmacological agents, the rapid progression of the cutaneous lesions, and their clinical presentation, alternative differential diagnoses were considered, including drug-induced reactions such as erythema multiforme or fixed drug eruption. A biopsy of the facial lesion revealed immunohistochemical positivity for CD10, CAIX, and PAX8, confirming the diagnosis of metastatic ccRC with sarcomatoid differentiation. Unfortunately, despite continued targeted therapies and palliative care, the patient’s condition deteriorated rapidly, leading to death two months later. This case highlights the potential for extremely rapidly evolving cutaneous metastases from ccRC and their capacity to occasionally mimic atypical drug eruptions. Additionally, it reaffirms the poor prognosis of such metastases, as evidenced by the patient’s death within two months. Full article