Background: Atopic dermatitis (AD) is a chronic relapsing inflammatory skin disease.Although murine studies have demonstrated that type 2 innate lymphoid cells (ILCs) mediate type 2 skin inflammation, their role in skin fibrosis in AD remains unclear. This study investigated whether type 2 ILCs are involved in skin fibrosis using an AD-like murine model. Methods: C57BL/6 mice were treated epicutaneously with Aspergillus fumigatus (Af) for 5 consecutive days per week for 5 weeks to induce skin fibrosis. Mature lymphocyte deficient Rag1−/− mice were also used to investigate the role of type 2 ILCs in skin fibrosis. Results: The clinical score and transepidermal water loss (TEWL) were significantly higher in the AD group than in the control group. The AD group also showed significantly increased epidermal and dermal thicknesses and significantly higher numbers of eosinophils, neutrophils, mast cells, and lymphocytes in the lesional skin than the control group. The lesional skin of the AD group showed increased stain of collagen and significantly higher levels of collagen than the control group (10.4 ± 2.2 µg/mg vs. 1.6 ± 0.1 µg/mg, P < 0.05). The AD group showed significantly higher populations of type 2 ILCs in the lesional skin compared to the control group (0.08 ± 0.01% vs. 0.03 ± 0.01%, P < 0.05). These findings were also similar with the AD group of Rag1−/− mice compared to their control group. Depletion of type 2 ILCs with anti-CD90.2 monoclonal antibodies significantly improved clinical symptom score, TEWL, and infiltration of inflammatory cells, and significantly decreased levels of collagen were observed in the AD group of Rag1−/− mice (1.6 ± 0.0 μg/mg vs. 4.5 ± 0.3 μg/mg, P < 0.001). Conclusion In the Af-induced AD-like murine model, type 2 ILCs were elevated, with increased levels of collagen. Additionally, removal of type 2 ILCs resulted in decreased collagen levels and improved AD-like pathological findings. These findings suggest that type 2 ILCs play a role in the mechanism of skin fibrosis in AD.

Background and Objectives: Blood pressure (BP) measurement using an auscultatory sphygmomanometer is recommended for diagnosing hypertension in children. As mercury sphygmomanometers (MSs) are banned owing to environmental concerns, it is crucial to determine the accuracy of mercury-free sphygmomanometers to replace them. We analyzed the accuracy of these devices to guide the National Survey selection. Methods: BP was measured thrice each with MS, auscultatory device (AD), and oscillometric device (OD) in 104 participants aged 10–18 using the National Survey data. The difference in BP was defined as the difference between MS and other devices. The BP differences, correlations, and influencing factors were analyzed. The frequencies of hypertension were also compared. Results: Systolic BP (SBP) and diastolic BP (DBP) differences between MS and AD were 0.88±3.36 mmHg and 0.63±3.95 mmHg, and those between MS and OD were 0.43±5.83 mmHg and 4.57±6.89 mmHg, respectively. The absolute error of <10 mmHg for DBP between MS and OD was 76%. The concordance correlation coefficient between MS and AD was 0.94 for SBP and 0.90 for DBP, and 0.81 and 0.67, respectively for MS and OD. Arm circumference negatively correlated with BP differences except for SBP between the MS and OD. The frequency of hypertension was not different between MS and AD but was underestimated by OD. Conclusions AD correlated well with MS, while OD did not, especially for DBP. The superiority of AD over OD suggests AD as a possible alternative for MS in the National Survey.

Purpose: Food sensitization to egg white (EW) peaks during early childhood, after which some children with sensitization to EW outgrow food sensitization, while others develop an increased degree of sensitization to EW. We investigated factors determining changes in EW-specific IgE in children under 2 years of age. Methods: Among children under 2 years of age with atopic dermatitis or food allergy who visited Asan Medical Center from March 2018 to September 2021, a total of 172 sensitized to EW were enrolled. Serum specific IgE to EW, ovalbumin and ovomucoid, and specific IgG4 to EW and ovomucoid were measured at 0, 6, and 12 months. An increase in EW-specific IgE was defined as an increased level of EW-specific IgE after 12 months from baseline. Multiple logistic regression analysis was performed to identify factors determining an increase in EW-specific IgE. Results: Of the 172 children, 85 had complete data on serum specific IgE and specific IgG4 during a period of 12 months. The levels of EW-specific IgE were decreased in 51 subjects (60.0%), while they were increased in 34 subjects (40.0%). Introduction of baked eggs had a protective effect against an increase in EW-specific IgE levels during a period of 12 months (adjusted odds ratio, 0.148; 95% confidence interval, 0.022–0.983). Conclusion Introduction of the baked egg can prevent an increase in EW-specific IgE during early childhood. Further studies are needed for the long-term effect of baked egg on the natural course of EW sensitization.

Purpose: Sixty to eighty percent of children with egg allergy are able to tolerate eggs in baked form. The purpose of this study was to evaluate the clinical usefulness and diagnostic value of measurements of IgE specific to egg white, ovalbumin, and ovomucoid for reactivity to baked egg in children with sensitivity to egg. Methods: Two hundred seventeen children with suspected egg allergy underwent open food challenges with baked egg (in the form of muffins). The outcomes of the challenges were compared to the serum concentrations of IgE specific to egg white, ovalbumin, and ovomucoid by using ImmunoCAP. Results: There were no statistically significant differences in levels of IgE specific to egg white, ovalbumin, and ovomucoid between the baked egg challenge positive and negative groups younger than 2 years (n = 163). However, significant differences were observed between the challenge positive and negative groups in 54 subjects aged 2 to 5 years (all P < 0.05). The optimal cutoff points of egg white, ovalbumin, and ovomucoid specific IgE levels among children aged 2 to 5 years were 12.40 kU A/L (sensitivity 79%, specificity 66%), 4.07 kU A/L (sensitivity 88%, specificity 58%), and 3.65 kU A/L (sensitivity 77%, specificity 62%), respectively. Conclusion The level of IgE specific to egg white and its components can predict the reactivity to baked egg in children aged 2 to 5years.

Background: Recently, CrpP enzymes have been described as a novel cause of ciprofloxacin resistance. The crpP gene encodes a novel protein that specifically confers resistance to ciprofloxacin through an adenosine triphosphate-dependent mechanism that phosphorylates the antimicrobial. In this study, the current prevalence of the crpP gene in carbapenemaseproducing Pseudomonas aeruginosa blood isolates was evaluated. Methods: During the study of the Antimicrobial Resistance Surveillance System in Korea, 22 blood isolates of carbapenemase-producing P. aeruginosa were collected from nine general hospitals and two nursing homes in the year 2020. Resistance genes and phylogenic trees were analyzed with the whole genome sequencing data. Results: A total of 11 P. aeruginosa blood isolates coharbored the crpP and carbapenemase genes (nine IMP-6 producers and two GES-5-producers). Nine NDM-1-producers coharbored aac(6')-Ib-cr and qnrVC1 . One GES-9-producer also carried aac(6')-Ib-cr, and one NDM-1-producer also carried qnrVC1. The phylogenic tree showed no epidemiologic link among the 22 carbapenemase-producing P. aeruginosa isolates. Conclusion This is the first report on the current prevalence of the crpP gene in carbapenemaseproducing P. aeruginosa blood isolates in Korea.

Purpose: Mycoplasma pneumoniae pneumonia (MP) is a major cause of community-acquired pneumonia (CAP) in children and is associated with extrapulmonary manifestations (EPM). The incidence and risk factors for EPM in children are unknown. Methods: This was a retrospective study involving 65,243 pediatric patients with CAP between 2010 and 2015 at 23 nationwide hospitals in South Korea. Medical records were reviewed to collect information regarding the clinical characteristics, radiological results, and laboratory findings. Logistic regression with multivariate analysis was performed to evaluate the risk factors associated with EPM in MP. Results: The incidence of EPM was 23.9%, including elevation of liver enzymes (18.1%), mucocutaneous manifestations (4.4%), proteinuria (4.1%), cardiovascular and neurological manifestations (0.4%), hematologic manifestations (0.2%), and arthritis (0.2%). Statistical analysis showed that mucocutaneous manifestations significantly increased with elevated alanine aminotransferase (adjusted odds ratio [aOR], 3.623; 95% confidence interval [CI], 1.933-6.790) and atopic sensitization (aOR, 2.973; 95% CI, 1.615–5.475) and decreased with respiratory virus coinfection (aOR, 0.273; 95% CI, 0.084–0.887). Elevated liver enzymes were significantly associated with elevated lactate dehydrogenase (aOR, 3.055; 95% CI, 2.257–4.137), presence of pleural effusion (aOR, 2.635; 95% CI, 1.767–3.930), and proteinuria with respiratory virus coinfection (aOR, 2.245; 95% CI, 1.113–4.527). Conclusion Approximately 24% of pediatric patients with MP had various EPM. As the risk factors associated with each EPM were different, it is necessary to evaluate the various clinical aspects and findings of MP to predict and prepare for the occurrence of EPM.

Background: Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease mediated by T helper type 2 (Th2) cells in acute phase. Group 2 innate lymphoid cells (ILCs) play a role in the initiation of the Th2 response. Although mold exposure is associated with the development of AD, studies on the underlying mechanisms are lacking. This study investigated whether group 2 ILCs are involved in inflammation in AD-like skin induced by Aspergillus fumigatus (Af). Methods: We investigated changes of group 2 ILCs population in Af-induced AD-like skin lesions. To induce AD-like skin lesions, Af extracts were applied to the dorsal skin of BALB/c and Rag1−/− mice five times per week, with repeat exposures at 2-week intervals. Results: The clinical parameters were higher in the Af-treated group than in the control group. Histologic findings revealed epiderrmal and dermal thickening as well as eosinophil and mast cell infiltration into the skin of Af-treated mice. Populations of group 2 ILCs in the skin were also significantly higher in the Af-treated group. In addition, interleukin-33 mRNA expression was significantly higher in the skin lesions of the Af-treated mice. In the Rag1−/− mice lacking mature lymphocytes, AD-like skin lesions were still induced by Af and ILCs depletion using an anti-CD90.2 mAb lowered the Af-induced inflammatory response. Conclusions Group 2 ILCs may play a role in a murine model of Af-induced AD-like skin lesions.

In this study, we intended to describe an unrecorded species of heterophyid trematode recovered from the small intestine of a Korean raccoon dog, Nyctereutes procyonoides koreensis, in Korea. A total of 13 small flukes were collected from a deceased Korean raccoon dog which was found in Chuncheon-si, Gangwon-do, Korea in May 2017. The trematode body were covered with many small spines, rectangular, broader than long, 807-1,103 µm long and 1,270-1,550 µm wide. Oral sucker in the anterior end slightly smaller than acetabulum. Pharynx muscular and well developed. Esophagus relatively long and sigmoid. Acetabulum small and located at median in anterior 2/5 portion. Ceca bifurcated at the anterior of genital pore and acetabulum and terminated at testis level. Testes larger, deeply lobed and located at the near of posterior end of body. Ovary small, triangular and located at the slight left of median and the anterior of left testis. Vitelline follicles dendritic and extend from the middle level of esophagus to the posterior portion of body. Eggs embryonated, operculated, small and 33-35×15-16 µm in size. Based on the morphological characteristics, the small heterophyid flukes recovered from the small intestines of Korean raccoon dog, N. procyonoides koreensis, were identified as Euryhelmis squamula (Digenea: Heterophyidae). Accordingly, this species of heterophyid flukes is to be a new trematode fauna in Korea by this study.

Canine T-zone lymphoma (TZL) is a mature T-cell lymphoma in dogs. The diagnosis and sub-classification are impossible without biopsy or immunophenotyping by flow cytometry. An 11-year-old, spayed, female Golden Retriever presented with lymph node enlargement. Clinical examination was consistent with canine multicentric lymphoma. However, immunophenotyping revealed positive for CD3, CD4, CD5, CD8, CD21, TCRαβ, and MHCII but negative for CD34, CD45, CD79a, and TCRγδ. Histopathology revealed lymphocytes expanding to the cortex-preserving architecture and thinning of the nodal capsule, and CD3 positive but PAX-5 negative. Owing to the indolent nature of TZL, careful monitoring approach without clinical intervention was utilized.

In this study, we intended to describe an unrecorded species of heterophyid trematode recovered from the small intestine of a Korean raccoon dog, Nyctereutes procyonoides koreensis, in Korea. A total of 13 small flukes were collected from a deceased Korean raccoon dog which was found in Chuncheon-si, Gangwon-do, Korea in May 2017. The trematode body were covered with many small spines, rectangular, broader than long, 807-1,103 µm long and 1,270-1,550 µm wide. Oral sucker in the anterior end slightly smaller than acetabulum. Pharynx muscular and well developed. Esophagus relatively long and sigmoid. Acetabulum small and located at median in anterior 2/5 portion. Ceca bifurcated at the anterior of genital pore and acetabulum and terminated at testis level. Testes larger, deeply lobed and located at the near of posterior end of body. Ovary small, triangular and located at the slight left of median and the anterior of left testis. Vitelline follicles dendritic and extend from the middle level of esophagus to the posterior portion of body. Eggs embryonated, operculated, small and 33-35×15-16 µm in size. Based on the morphological characteristics, the small heterophyid flukes recovered from the small intestines of Korean raccoon dog, N. procyonoides koreensis, were identified as Euryhelmis squamula (Digenea: Heterophyidae). Accordingly, this species of heterophyid flukes is to be a new trematode fauna in Korea by this study.