Erythrodermic psoriasis is a severe and potentially life-threatening dermatologic condition that can be triggered or unmasked by medications. We report the case of a 73-year-old patient who developed new-onset erythrodermic psoriasis following treatment with antiepileptic drugs (AEDs), specifically carbamazepine and levetiracetam, for autoimmune encephalitis. Despite discontinuation of the AEDs, the patient's condition persisted and improved only after systemic biological therapy. Clinical presentation, together with histopathologic findings, supported a diagnosis of new-onset psoriasis rather than a drug-induced psoriasiform reaction. This case highlights the importance of recognizing AEDs as potential triggers for psoriasis in patients with no prior history. Given the severe complications associated with erythroderma, timely diagnosis and initiation of appropriate therapy are essential. Clinicians should maintain a high index of suspicion for medication-induced dermatologic conditions in patients presenting with new or progressive skin eruptions.

Exfoliative erythroderma is a severe inflammatory skin condition that may result from pre-existing dermatoses, medications, or underlying malignancy. Although malignancy-associated cases are uncommon, persistent and treatment-resistant erythroderma should raise concern for an occult cancer. We report the case of an 82-year-old man with a one-year history of diffuse pruritic erythema and scaling involving nearly the entire body surface area that remained refractory to multiple dermatologic and immunosuppressive therapies. Initial evaluation for cutaneous lymphoma and systemic malignancy was negative. Months later, the patient developed a generalized seizure, and a brain MRI revealed a right frontal lobe mass. Biopsy later confirmed Epstein-Barr virus-positive primary central nervous system diffuse large B-cell lymphoma. This case highlights persistent exfoliative erythroderma as a potential paraneoplastic manifestation of an underlying malignancy and emphasizes the importance of continued evaluation for occult cancer when erythroderma remains unexplained and refractory to treatment.

A 66-year-old woman with a 6-month history of new-onset psoriasis after her first dose of COVID-19 vaccination recently progressed to acute erythroderma accompanied by fever and systemic inflammation. She was started on secukinumab for erythrodermic psoriasis (EP) after conventional therapies were contraindicated. On hospital day 6, her condition deteriorated with dyspnea, high fever, and edema. Laboratory evaluation revealed severe hypoalbuminemia and elevated inflammatory cytokines, with no evidence of infection. Imaging studies showed pulmonary edema and massive pleural effusions requiring therapeutic thoracentesis. After excluding sepsis, cardiogenic pulmonary edema, and allergic reactions, a diagnosis of systemic capillary leak syndrome (SCLS) complicating EP was established. Secukinumab was discontinued, and the patient received supportive care while being switched to apremilast. Her condition improved rapidly, with resolution of fever, reduction in pleural effusions, and significant diminishment of skin erythema. This case highlights a rare but life-threatening complication of severe acute EP, as both conditions are driven by a systemic cytokine storm. A single loading dose of secukinumab failed to effectively control the systemic cytokine storm in this patient, and the potential association between secukinumab administration and disease progression requires further investigation. We review the pathogenesis of EP, differentiate it from plaque psoriasis, identify the risk factors for SCLS, and discuss therapeutic considerations. Clinicians managing patients with severe psoriasis should remain vigilant for the potential occurrence of SCLS, particularly in those presenting with acute EP. Additionally, careful consideration should be given to the selection of biologic agents in high-risk patients.

Introduction Adult exfoliative dermatitis (ED) is a severe inflammatory dermatosis with heterogeneous etiologies and substantial morbidity. Hospital-based prospective data remain limited in Thailand. We aimed to prospectively describe the clinical characteristics, etiologies, management, and outcomes of adults with ED at a tertiary-care hospital in Thailand, and to assess changes during follow-up. Methods We conducted a prospective hospital-based cohort study enrolling consecutive adults diagnosed with ED from November 2024 to March 2026. Baseline demographics, comorbidities, prior treatments, clinical manifestations, and disease severity were recorded. Etiology was determined by clinicopathologic correlation and treating-physician adjudication. Patients were followed longitudinally for up to 12 months after diagnosis, and changes in disease severity and clinical outcomes were assessed during follow-up. Analyses were primarily descriptive. Exploratory comparisons across follow-up visits were reported using nonparametric tests with corresponding p-values. Results Thirty-four patients were recruited; two were lost to follow-up, and one had incomplete baseline data, leaving 31 for analysis. The mean age was 58.0 ± 18.2 years, and 74.2% were male. Most were managed as outpatients (67.7%), while 32.3% required hospitalization. Pruritus, scaling, and erythema were present in all patients. Nail involvement was frequent (64.5%), whereas pustules and mucosal involvement were uncommon (6.5% each). Systemic features occurred in a subset, including arthritis (25.8%), fever (16.1%), edema (16.1%), and lymphadenopathy (6.5%). Conclusions In this prospective hospital-based cohort, adult ED demonstrated uniform core cutaneous features with variable systemic involvement and a substantial proportion requiring hospitalization. These findings provide pragmatic clinical profiles to support early recognition and structured evaluation of etiology and complications in routine practice.

Palisaded neutrophilic and granulomatous dermatitis (PNGD) is a reactive granulomatous dermatitis; the umbrella term includes interstitial granulomatous dermatitis and interstitial granulomatous drug reaction, in addition to PNGD. The histological findings of PNGD include leukocytoclastic vasculitis, neutrophilic infiltrates, and collagen degeneration with palisades of histiocytes and small granulomas. Clinically, the patients show symmetrical, smooth papules that are skin-colored to red, some with central umbilication or crusting, located mainly on the elbows and extremities. PNGD usually occurs with some systemic diseases, such as systemic lupus erythematosus, suggesting a cutaneous reaction pattern due to underlying internal inflammation. Although the present case was histologically diagnosed as PNGD, while excluding other granulomatous diseases, multiple indurated erythematous papules with a tendency to coalesce widely were seen, mimicking erythroderma without any underlying immunological diseases. In addition, the eruption coincided with fluctuating high fever. This was a rare case of PNGD with no underlying immunological disease that presented with severe manifestations such as fever and erythroderma.

Cartilage hair hypoplasia (CHH) syndrome (OMIM #250250) is a rare autosomal recessive metaphyseal dysplasia, characterized by disproportionate short stature, hypotrichosis and variable extra-skeletal manifestations, including immunodeficiency, anemia, intestinal diseases, and predisposition to malignancies. CHH results from homozygous or compound heterozygous mutations in the RMRP gene on chromosome 9p13, which encodes an untranslated RNA component of mitochondrial RNA-processing endoribonuclease. RMRP pathogenic variants can also lead to Omenn Syndrome (OS) (OMIM #603554), a systemic inflammatory condition displaying neonatal erythroderma and immunodeficiency. This report highlights the genotypic and phenotypic overlap between CHH and OS, by presenting a newborn with skeletal dysplasia, immunodeficiency and neonatal onset erythroderma, carrying the homozygous NR_003051:n.35C > A variant in the RMRP gene.

Cutaneous paraneoplastic syndromes (CPSs) in cats represent a diverse group of rare dermatological manifestations that occur as indirect consequences of underlying neoplasia. These syndromes are thought to arise due to tumour-associated systemic effects, including dysregulation of immune responses, metabolic disturbances and aberrant production of cytokines or growth factors. Recognising CPSs is clinically relevant, as they may serve as early indicators of occult neoplasia, guiding timely diagnosis and intervention.

Incontinentia Pigmenti (IP) is a rare X-linked genetic disorder characterised by four stages of cutaneous involvement: vesicular, verrucous, hyperpigmented and hypopigmented (Scheuerle AE, Ursini MV. Incontinentia Pigmenti. In: GeneReviews (Adam MP, eds). Seattle: University of Washington, 1999). Unusual first presentations may obscure the diagnosis and pose a significant diagnostic challenge. We present an atypical case of a female neonate born at thirty-seven weeks who developed a widespread erythematous rash shortly after birth covering over ninety percent of the body surface area. The erythema and associated blisters did not demonstrate a linear or blaschkoid distribution. There was no evidence of ocular, mucosal or extracutaneous involvement. Infection screen, virology and initial blood tests were unremarkable. Viral screening of the CSF was negative. Further investigation was pursued and DNA analysis of the IKBKG (NEMO) gene showed a deletion of exon 4-10 in this gene, the commonest underlying genetic cause of IP (Fusco F, Bardaro T, Fimiani G et al. Molecular analysis of the genetic defect in a large cohort of IP patients and identification of novel NEMO mutations interfering with NF-kappaB activation. Hum Mol Genet 2004;13:1763-73). This case highlights erythroderma as an atypical initial manifestation of IP, deviating from its classic cutaneous presentation. The aetiology of erythroderma in the neonate has several differentials and this case highlights the importance of considering rarer diagnoses even in the absence of hallmark features. Early recognition can facilitate family counselling and monitoring for extracutaneous involvement in this multi-system disorder.