Background: The Omicron variant has become the most prevalent SARS-CoV-2 variant. Omicron is known to induce milder lesions compared to the original Wuhan strain. Fatal infection of the Wuhan strain into the brain has been well documented in COVID-19 mouse models and human COVID-19 cases, but apparent infections into the brain by Omicron have not been reported in human adult cases or animal models. In this study, we investigated whether Omicron could spread to the brain using K18-hACE2 mice susceptible to SARS-CoV-2 infection. Results: K18-hACE2 mice were intranasally infected with 1 × 105 PFU of the original Wuhan strain and the Omicron variant of SARS-CoV-2. A follow-up was conducted 7 days post infection. All Wuhan-infected mice showed > 20% body weight loss, defined as the lethal condition, whereas two out of five Omicron-infected mice (40%) lost > 20% body weight. Histopathological analysis based on H&E staining revealed inflammatory responses in the brains of these two Omicron-infected mice. Immunostaining analysis of viral nucleocapsid protein revealed severe infection of neuron cells in the brains of these two Omicron-infected mice. Lymphoid depletion and apoptosis were observed in the spleen of Omicron-infected mice with brain infection. Conclusion Lethal conditions, such as severe body weight loss and encephalopathy, can occur in Omicron-infected K18-hACE2 mice. Our study reports, for the first time, that Omicron can induce brain infection with lymphoid depletion in the mouse COVID-19 model.

Erythema nodosum (EN) is the most common form of panniculitis and may be triggered by a variety of stimuli, including infections, drugs, pregnancy, sarcoidosis, inflammatory bowel disease, and malignancies. Rare cases of vaccination-related EN have been reported, but none due to the coronavirus disease 2019 (COVID-19) vaccine of Pfizer have been documented. We report a case of EN associated with the Pfizer vaccine. A 43-year-old woman presented with acute-onset painful nodular lesions that appeared bilaterally on the extensor surface of the lower legs. These lesions appeared 5 days after the first dose of Pfizer vaccination. The patient reported no recent infectious history other than fever for 3 days after vaccination. Skin biopsy revealed inflammation extending into the subcutaneous fat with a septal distribution. It is important for physicians to be aware of the side effects of the COVID-19 vaccine because more people are bound to be vaccinated.

Prurigo pigmentosa (PP) is a rare inflammatory skin disease that commonly affects Asian women. It is characterized by symmetric pruritic eruptions in a reticular pattern, primarily on the back, chest, or neck. The etiology of PP is unclear; however, it is estimated that neutrophil-mediated inflammation of the skin is induced by various exogenous stressors, such as friction from clothing and sweating. In addition to exogenous factors, some cases are thought to be related to ketosis, diabetes mellitus, fasting, or dieting to lose weight. With the increasing popularity of ketogenic diets, cases of PP are being more commonly reported. To raise awareness of this disease, we present two cases of PP that occurred after following a ketogenic diet.

Background: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are potentially fatal acute hypersensitivity reactions that involve the skin and mucous membranes. Because they are relatively rare diseases, it is difficult to obtain well-organized epidemiological data. The clinicodemographic characteristics, culprit drugs, and factors related to disease prognosis may vary. Objective: To identify the characteristics of SJS/TEN by investigating patient clinicopathological characteristics, laboratory findings, suspected drugs, and mortality through a retrospective study using medical record data. Methods: The clinical records of patients diagnosed with SJS/TEN between February 2009 and February 2019 at three medical institutions of Soonchunhyang University were retrospectively reviewed. Data pertaining to sex, age, history, suspected drugs, latent period, laboratory findings, and mortality were collected, and their correlations were analyzed. Results: We identified SJS/TEN in 88 patients. Among the probable causative agents, antibiotics were the most common (29 cases, 33.0%), followed by nonsteroidal anti-inflammatory drugs (NSAIDs) in 20 cases (22.7%). The period between drug administration and symptom onset varied with the causative agent. Patients who died had high SCORTEN scores. In addition, hypertension, diabetes, renal failure, and cardiac disease had a statistically significant association with high SCORTEN. Conclusion Antibiotics, NSAIDs, antiepileptics and allopurinol were the most commonly implicated drugs in our retrospective study. There was a significant correlation between comorbidities. Because SJS/TEN is a life-threatening condition, early recognition of the suspected drug are important. The results of this study may provide insights that aid in the early diagnosis and prediction of disease outcomes of SJS/TEN in the Korean population.

Background: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are potentially fatal acute hypersensitivity reactions that involve the skin and mucous membranes. Because they are relatively rare diseases, it is difficult to obtain well-organized epidemiological data. The clinicodemographic characteristics, culprit drugs, and factors related to disease prognosis may vary. Objective: To identify the characteristics of SJS/TEN by investigating patient clinicopathological characteristics, laboratory findings, suspected drugs, and mortality through a retrospective study using medical record data. Methods: The clinical records of patients diagnosed with SJS/TEN between February 2009 and February 2019 at three medical institutions of Soonchunhyang University were retrospectively reviewed. Data pertaining to sex, age, history, suspected drugs, latent period, laboratory findings, and mortality were collected, and their correlations were analyzed. Results: We identified SJS/TEN in 88 patients. Among the probable causative agents, antibiotics were the most common (29 cases, 33.0%), followed by nonsteroidal anti-inflammatory drugs (NSAIDs) in 20 cases (22.7%). The period between drug administration and symptom onset varied with the causative agent. Patients who died had high SCORTEN scores. In addition, hypertension, diabetes, renal failure, and cardiac disease had a statistically significant association with high SCORTEN. Conclusion Antibiotics, NSAIDs, antiepileptics and allopurinol were the most commonly implicated drugs in our retrospective study. There was a significant correlation between comorbidities. Because SJS/TEN is a life-threatening condition, early recognition of the suspected drug are important. The results of this study may provide insights that aid in the early diagnosis and prediction of disease outcomes of SJS/TEN in the Korean population.

Background: In 2015, the Korean Atopic Dermatitis Association (KADA) working group published consensus guidelines for treating atopic dermatitis (AD). Objective: We aimed to provide updated consensus recommendations for systemic treatment of AD in South Korea based on recent evidence and experience. Methods: We compiled a database of references from relevant systematic reviews and guidelines on the systemic management of AD. Evidence for each statement was graded and classified based on thestrength of the recommendation. Forty-two council members from the KADA participated in three rounds of voting to establish a consensus on expert recommendations. Results: We do not recommend long-term treatment with systemic steroids forpatients with moderate-to-severe AD due to the risk of adverse effects. We recommend treatment with cyclosporine or dupilumab and selective treatment with methotrexate or azathioprine for patients with moderate-to-severe AD. We suggest treatment with antihistamines as an option for alleviating clinical symptoms of AD. We recommend selective treatment with narrowband ultraviolet B for patients with chronic moderate-to-severe AD. We do not recommend treatment with oral antibiotics for patients with moderate-to-severe AD but who have no signs of infection. We did not reach a consensus on recommendations for treatment with allergen-specific immunotherapy, probiotics, evening primrose oil, orvitamin D for patients with moderate-to-severe AD. We also recommend educational interventions and counselling for patients with AD and caregivers to improve the treatment success rate. Conclusion We look forward to implementing a new and updated consensus of systemic therapy in controlling patients with moderate-to-severe AD.

BACKGROUND: Systemic immunomodulatory treatment is actively recommended in the treatment for moderate to severe atopic dermatitis (AD) patients. However, consensus criteria for the classification of AD severity or treatment refractoriness have not been established yet. OBJECTIVE: To establish consensus criteria on the definition of severity classification and treatment refractoriness of AD to provide a basis for proper treatment strategy. METHODS: The Korean Atopic Dermatitis Association (KADA) comprised a task force team to establish a definition of moderate to severe AD. A draft of definition of moderate to severe AD was made on the basis of evidence. The recommendation was confirmed by KADA members through a web-based survey. RESULTS: KADA approved that AD with 16≤eczema area and severity index (EASI)<23 should be basically defined as moderate AD whereas AD with EASI score ≥23 should be considered as severe AD. They agreed that it would be reasonable to raise the severity level if patient's daytime or nighttime pruritus numerical rating scale is equal to or higher than 7 (≥7) or dermatology life quality index score exceeds 10. AD patients who do not reach EASI 50 after appropriate treatment for three months should be considered as a non-responder. Patients with recurrence (EASI ≥16) within three months after cessation of treatment should be considered as a recurrent AD. CONCLUSION: KADA built a consensus of definition of moderate and severe AD and treatment-refractoriness. These guidelines are expected to help physicians determine proper treatment options in need.
Advisory Committees ; Classification ; Consensus ; Dermatitis, Atopic ; Dermatology ; Diagnosis ; Humans ; Pruritus ; Quality of Life ; Recurrence ; Treatment Failure ; Withholding Treatment

BACKGROUND: Topical tacrolimus is an effective anti-inflammatory therapy for acute and chronic states of atopic dermatitis (AD) in both adults and children. Topical tacrolimus has particular use at sensitive areas such as the face, anogenitals, and skin folds of neck and extremities. However, many AD patients also experience aggravated symptoms on trunk. OBJECTIVE: The aim of this study was to investigate the efficacy and safety of topical tacrolimus for AD patients with truncal lesions. METHODS: AD patients with truncal lesions who were aged ≥2 years were recruited from 20 centres in Korea. They received treatment with topical tacrolimus ointment twice daily during 4 weeks. The primary end point was change of the local eczema area and severity index (EASI) of the trunk from baseline to day 28. The secondary end points were changes in the patient global assessment (PGA) score and itch visual analogue scale (VAS) score of the trunk between baseline and day 28. RESULTS: Two hundred and ninety-one patients were recruited, and 176 patients completed the full 4-week treatment course. By the end of the treatment, the mean local EASI of the trunk (2.2±4.71) was significantly decreased from that at baseline (4.71±4.03, p < 0.001). PGA (1.71±1.15) and itch VAS score of the trunk (2.61±2.19) on day 28 were also profoundly decreased compared with the baseline (2.96±1.07 and 5.15±2.47, respectively). No serious adverse events were observed during the study period. CONCLUSION: Topical tacrolimus is an effective and safe therapy for truncal lesions in AD patients.
Administration, Topical ; Adult ; Child ; Dermatitis, Atopic* ; Eczema ; Extremities ; Humans ; Korea ; Neck ; Skin ; Tacrolimus*

BACKGROUND AND PURPOSE: Visual assessment of medial temporal-lobe atrophy (MTA) has been quick, reliable, and easy to apply in routine clinical practice. However, one of the limitations in visual assessments of MTA is the lack of widely accepted age-adjusted norms and cutoff scores for MTA for a diagnosis of Alzheimer's disease (AD). This study aimed to determine the optimal cutoff score on a T1-weighted axial MTA Visual Rating Scale (VRS) for differentiating patients with AD from cognitively normal elderly people. METHODS: The 3,430 recruited subjects comprising 1,427 with no cognitive impairment (NC) and 2003 AD patients were divided into age ranges of 50–59, 60–69, 70–79, and 80–89 years. Of these, 446 participants (218 in the NC group and 228 in the AD group) were chosen by random sampling for inclusion in this study. Each decade age group included 57 individuals, with the exception of 47 subjects being included in the 80- to 89-year NC group. The scores on the T1-weighted axial MTA VRS were graded by two neurologists. The cutoff values were evaluated from the area under the receiver operating characteristic curve. RESULTS: The optimal axial MTA VRS cutoff score from discriminating AD from NC increased with age: it was ≥as ≥1, ≥2, and ≥3 in subjects aged 50–59, 60–69, 70–79, and 80–89 years, respectively (all p < 0.001). CONCLUSIONS: These results show that the optimal cutoff score on the axial MTA VRS for diagnosing of AD differed according to the decade age group. This information could be of practical usefulness in the clinical setting.
Aged ; Alzheimer Disease* ; Atrophy* ; Cognition Disorders ; Dementia* ; Diagnosis ; Humans ; Korea* ; Pemetrexed ; ROC Curve