Bowel Wall Thickening on Computed Tomography in Children: A Novel Method of Measurement and Its Clinical Significance.

PURPOSE: The clinical implications of bowel wall thickening (BWT) on abdominal computed tomography (CT) among children are unknown. We aimed to suggest a new method for measuring BWT and determining its clinical significance in children. METHODS: We retrospectively analyzed 423 patients with acute abdomen who underwent abdominal CT; 262 were classified into the BWT group. For this group, the pediatric radiologist described the maximal bowel wall thickness (MT), normal bowel wall thickness (mm) (NT), and their ratios for each segment of the bowel wall. RESULTS: In the thickened bowel walls, the thickness differed significantly between the small bowel (6.83±2.14 mm; mean±standard deviation) and the colon (8.56±3.46 mm; p<0.001). The ratios of MT to NT in the small bowel (6.09±3.17) and the colon (7.58±3.70) were also significantly different (p<0.001). In the BWT group, 35 of 53 patients had positive fecal polymerase chain reaction results; 6 patients infected with viruses predominantly had BWT in the small intestine, while the terminal ileum and the colon were predominantly affected in 29 patients with bacterial infections. In the initially undiagnosed 158 patients with BWT, the symptoms improved spontaneously without progression to chronic gastrointestinal disease. CONCLUSION: This study provides a clinical reference value for BWT in the small intestine and colon using a new method in children. The BWT on abdominal CT in children might indicate nonspecific findings that can be observed and followed up without additional evaluation, unlike in adults.

The expressions of MUM-1 and Bcl-6 in ALK-negative systemic anaplastic large cell lymphoma with skin involvement and primary cutaneous anaplastic large cell lymphoma.

BACKGROUND: It is important to differentiate between primary cutaneous anaplastic large cell lymphoma (PC-ALCL) and ALK-negative systemic ALCL with skin involvement, as the prognoses and treatments for these two diseases are considerably different. OBJECTIVE: This study aimed to compare the expressions of multiple myeloma oncogene 1 (MUM-1) and B-cell lymphoma 6 (Bcl-6) in PC-ALCL and ALK-negative systemic ALCL. METHODS: This retrospective qualitative study investigated the clinical features of 7 patients with ALK-negative PC-ALCL, 5 patients with ALK-negative systemic ALCL with skin involvement, and 6 patients with ALK-positive systemic ALCL with skin involvement. The MUM-1 and Bcl-6 expressions were evaluated using immunohistochemistry. RESULTS: The MUM-1 expression rates were 85.7% in the PC-ALCL cases and 100% in the ALK-negative systemic ALCL with skin involvement cases. The Bcl-6 expression rates were 28.5% in the PC-ALCL cases and 20% in the ALK-negative systemic ALCL cases with skin involvement. CONCLUSION: Although the cutaneous manifestations of ALK-negative systemic ALCL and PC-ALCL are similar, the prognoses and treatment approaches are considerably different. Our results indicate that MUM-1 expression is commonly expressed in both types of ALCL, but Bcl-6 is less commonly expressed in PC-ALCL cases and systemic ALCL with skin involvement cases.

Comparative study of the bactericidal effects of indocyanine green- and methyl aminolevulinate-based photodynamic therapy on Propionibacterium acnes as a new treatment for acne.

Acne vulgaris is one of the most common dermatological problems, and its therapeutic options include topical and systemic retinoids and antibiotics. However, increase in problems associated with acne treatment, such as side-effects from conventional agents and bacterial resistance to antibiotics, has led to greater use of photodynamic therapy. The purpose of this study was to compare the bactericidal effects of indocyanine green- and methyl aminolevulinate-based photodynamic therapy on Propionibacterium acnes. P. acnes were cultured under anaerobic conditions; then they were divided into three groups (control, treated with indocyanine green and treated with methyl aminolevulinate) and illuminated with different lights (630-nm light-emitting diode, 805-nm diode laser and 830-nm light-emitting diode). The bactericidal effects were evaluated by comparing each group's colony-forming units. The cultured P. acnes were killed with an 805-nm diode laser and 830-nm light-emitting diode in the indocyanine green group. No bactericidal effects of methyl aminolevulinate-based photodynamic therapy were identified. The clinical efficacy of indocyanine green-based photodynamic therapy in 21 patients was retrospectively analyzed. The Korean Acne Grading System was used to evaluate treatment efficacy, which was significantly decreased after treatment. The difference in the efficacy of the 805-nm diode laser and 830-nm light-emitting diode was not statistically significant. Although the methyl aminolevulinate-based photodynamic therapy showed no bactericidal effect, the indocyanine green-based photodynamic therapy has bactericidal effect and clinical efficacy.

Antibiotics-Associated Hemorrhagic Colitis Caused by Klebsiella oxytoca: Two Case Reports.

Nowadays, Klebsiella oxytoca is described as a causative organism for antibiotic-associated hemorrhagic colitis (AAHC). Here we report two cases of pediatric AAHC, from which K. oxytoca was cultured after starting amoxicillin-clavulanate or amoxicillin treatment. The patients developed severe abdominal pain and a large amount of bloody diarrhea. K. oxytoca was obtained in intestinal fluid culture of a boy through the colonoscopy. On the other hand, colonic tissue culture and intestinal fluid culture were negative of the other patient. K. oxytoca was detected in stool culture when he was admitted. These cases showed characteristic endoscopic findings of segmental hemorrhagic colitis, and both boys recovered spontaneously within 2-3 days after they stopped taking the antibiotics. Therefore, in children who develop relatively large amount of bloody diarrhea after antibiotic treatment, we should consider AAHC caused by K. oxytoca.

Clinical features and prognosis of Asian patients with acral lentiginous melanoma who have nodal nevi in their sentinel lymph node biopsy specimen.

BACKGROUND: Nodal melanocytic nevi (NNs) encountered during sentinel lymph node biopsy (SLB) for malignant melanoma are usually difficult to distinguish from metastatic melanoma. However, NNs have not been well studied in acral lentiginous melanoma (ALM) in Asian populations. OBJECTIVE: To investigate the clinical characteristics and significance of NNs in SLB specimens from patients with ALM. METHODS: We retrospectively analyzed 84 patients with ALM who underwent SLB between June 2010 and July 2017. RESULTS: Of the 84 patients with ALM, 9 (10.7%) had NNs in their SLB specimens. NNs were significantly more common in SLB specimens than in specimens not obtained by SLB. The presence of pre-existing melanocytic lesions was found to be associated with NNs (P < .001). The 5-year overall survival was significantly higher in patients with ALM with NNs than in patients with a positive SLB result (P = .047). Distant recurrence in patients with ALM with NNs was significantly lower than in patients a positive SLB result (P = .03). LIMITATIONS: The small sample size, single-center study design, and retrospective nature of the study were the limitations. CONCLUSION: In Asian populations, the prevalence of NNs in ALM is similar to that reported in Europe and the United States. The rates of distant recurrence and overall survival in patients with ALM who have NNs are similar to those of patients who do not have metastatic melanoma.

Role of Treg and TH17 cells of the gastric mucosa in children with Helicobacter pylori gastritis.

OBJECTIVE: The aim of the present study was to examine the expression of FOXP3, interleukin (IL)-10, transforming growth factor (TGF)-ß1, IL-17A, and T helper 17 (TH17) cells/FOXP3+ regulatory T (Treg) cells balance in the gastric mucosa of children with Helicobacter pylori infection, in relation to the gastric histopathology. METHODS: Antral mucosal biopsies were obtained from 20 children with H pylori(+) gastritis and 20 age- and sex-matched normal controls. Histopathology was assessed by the updated Sydney classification. Gene expression of FOXP3, IL-10, and TGF-ß1 was analyzed by quantitative real-time polymerase chain reaction. Immunohistochemical staining for FOXP3+ Treg and TH17 cells was performed. RESULTS: The gene expression levels of FOXP3, TGF-ß1, and IL-10 messenger RNA (mRNA) and the number of FOXP3+ Treg were significantly higher in the H pylori(+) gastritis group than in the control group (P < 0.01). FOXP3 mRNA levels were correlated positively with TGF-ß1 and IL-10 mRNA levels in the H pylori(+) gastritis group (P < 0.05). Furthermore, FOXP3 mRNA levels were correlated positively with the bacterial density, infiltration of polymorphonuclear cells, and mononuclear cells in the H pylori(+) gastritis group (P < 0.05). The number of TH17 cells was significantly higher in the H pylori(+) gastritis group than in the control group (P < 0.05). In addition, the number of TH17 cells was correlated negatively with the bacterial density and positively with the inflammatory scores of polymorphonuclear cells and mononuclear cells in the H pylori(+) gastritis group (P < 0.05). A negative correlation between the TH17 cells/FOXP3+ Treg ratio and the bacterial density was demonstrated in the H pylori(+) gastritis group (P < 0.05). CONCLUSIONS: This study suggested that a TH17/Treg balance toward a Treg-biased response favors the persistence of bacteria, causing chronic active gastritis.

Congenital chloride diarrhea in Korean children: novel mutations and genetic characteristics.

UNLABELLED: Congenital chloride diarrhea (CLD, OMIM#214700) is an autosomal recessive disorder caused by mutations in the solute carrier family 26 member 3 (SLC26A3) gene, which encodes an intestinal chloride/bicarbonate exchanger. While more than 50 mutations have been identified throughout the world, there have been no data on the genetic characteristics of the patients of East Asian ethnic origin. In this study, we performed genetic analysis by direct sequencing of the 20 exons and parts of exon-intron boundaries of the SLC26A3 gene in eight patients of Korean origin with non-consanguineous parents. We identified three novel mutations, including two splice-site mutations (c.2063-1G>T in intron 18, c.1047+3 A>C in intron 12) and one missense mutation (p.Ser134Asn in exon 5). One previously identified mutation was also found (p.Pro131Leu in exon 5). The most common mutation was c.2063-1G>T, which was found in at least one allele of all patients. CONCLUSION: This is the first report to demonstrate the genetic background of CLD in a single ethnic group of East Asian descent. The c.2063-1G>T mutation could be suggested as a founder mutation in Korean population so that the targeting sequencing for the mutation would be a cost-efficient screening method to confirm a diagnosis of CLD in patients of Korean descent.

FOXP3+ regulatory T cells in children with helicobacter pylori infection.

Despite an intensive pro-inflammatory response, the immune system is unable to clear the organism in Helicobacter pylori gastritis. Regulatory T (Treg) cells, which suppress the immune response of antigen-specific T cells, have recently been demonstrated to play a key role in chronic inflammation by immunologic tolerance. The purpose of our study was to investigate the histopathology, FOXP3+CD4+CD25(high)Treg (FOXP3+Treg) cell expression, and immune responses in children with H. pylori infection. Twenty-four H. pylori -positive and 24 H. pylori -negative children who underwent esophagogastroduodenoscopy for dyspeptic symptoms were included. Histopathologic grading according to the updated Sydney classification and immunohistochemical stains for FOXP3, transforming growth factor-ß1 (TGF-ß1), and CD4 were performed. Histopathologic bacterial density score, gastritis activity score, and chronic inflammation score were higher in the H. pylori -positive group than in the negative group (P < 0.01). The number of FOXP3+Treg cells and CD4+T cells and the grade of TGF-ß1 expression were significantly increased in the H. pylori -positive group compared to the negative group (P < 0.01). The number of FOXP3+Treg cells correlated positively with the grade of TGF-ß1 expression regardless of H. pylori status (P < 0.05). The number of FOXP3+Treg cells and the grade of TGF-ß1 expression correlated positively with H. pylori density, gastritis activity score, and chronic inflammation score regardless of H. pylori status (P < 0.01). These findings indicate that FOXP3+Treg cells could play a role in persistent H. pylori infection.

Enterovirus 71-associated hand, foot and mouth diseases with neurologic symptoms, a university hospital experience in Korea, 2009.

PURPOSE: Hand-foot-mouth disease (HFMD) is a common viral illness in children, which is usually mild and self-limiting. However, in recent epidemics of HFMD in Asia, enterovirus 71 (EV71) has been recognized as a causative agent with severe neurological symptoms with or without cardiopulmonary involvement. HFMD was epidemic in Korea in the spring of 2009. Severe cases with complications including death have been reported. The clinical characteristics in children with neurologic manifestations of EV71 were studied in Ewha Womans University Mokdong Hospital. METHODS: Examinations for EV71 were performed from the stools, respiratory secretion or CSF of children who presented neurologic symptoms associated with HFMD by realtime PCR. Clinical and radiologic data of the patients were collected and analyzed. RESULTS: EV71 was isolated from the stool of 16 patients but not from respiratory secretion or CSF. Among the 16 patients, meningitis (n=10) was the most common manifestation, followed by Guillain-Barré syndrome (n=3), meningoencephalitis (n=2), poliomyelitis-like paralytic disease (n=1), and myoclonus (n=1). Gene analysis showed that most of them were caused by EV71 subgenotype C4a, which was prevalent in China in 2008. CONCLUSION: Because EV71 causes severe complications and death in children, a surveillance system to predict upcoming outbreaks should be established and maintained and adequate public health measures are needed to control disease.

Outbreak of rotavirus variant P[8] in Seoul, South Korea.

An epidemiologic study was performed to determine the genetic variability of rotaviruses in Seoul, South Korea. In 3,174 stool specimens from children with acute diarrhea at five referral hospitals, 571 (18%) possessed the antigen of group A rotavirus detectable by ELISA--10.8% in 2004 and 28.1% in 2005. VP7 genotyping revealed that the G3 type was found in 25.6% of all typed isolates, G4 in 23.8%, G2 in 21.6%, and G1 in 17.6%. VP4 genotyping showed that the P[8] type was detected in 66.7%, P[6] in 15.6%, P[4] in 13.0%, and P[9] in 0.2%. Because the variant P[8] type could not be amplified initially by conventional P typing primers (1T-1), PCR were performed using newly designed 1T-1S primer, which revealed that 307 specimens were the variant P[8] type. Uncommon combinations such as G4P[6] and G2P[8] were also found with relatively high prevalence, 14.6% and 12.8%, respectively. Variant P[8] types were associated with an outbreak of rotavirus in 2005.

Fulminant myocarditis successfully treated with high-dose immunoglobulin.

Fulminant myocarditis is characterized by the rapid development of life-threatening congestive heart failure. Intravenous immunoglobulin (IVIG), by modulating the immune response, may be used for the treatment of acute myocarditis. We report two children with fulminant myocarditis successfully treated with a 10-h infusion of high-dose IVIG. In those cases, a dramatic clinical improvement was achieved, with both cardiac enzymes and myocardial function normalized within 1-2 weeks after treatment.

Adherent cells generated during long-term culture of human umbilical cord blood CD34+ cells have characteristics of endothelial cells and beneficial effect on cord blood ex vivo expansion.

Hematopoiesis depends on the association of hematopoietic stem cells with stromal cells that constitute the hematopoietic microenvironment. The in vitro development of the endothelial cell from umbilical cord blood (UCB) is not well established and has met very limited success. In this study, UCB CD34(+) cells were cultured for 5 weeks in a stroma-free liquid culture system using thrombopoietin, flt3 ligand, and granulocyte-colony stimulating factor. By week 4-5, we found that firmly adherent fibroblast-like cells were established. These cells showed characteristics of endothelial cells expressing von Willebrand factor, human vascular cell adhesion molecule-1, human intracellular adhesion molecule-1, human CD31, E-selectin, and human macrophage. Furthermore, when comparing an ex vivo system without an established endothelial monolayer to an ex vivo system with an established endothelial monolayer, better expansion of total nucleated cells, CD34(+) cells, and colony-forming units (CFUs)-granulocyte-macrophage and CFUs-granulocyte-erythroid-megakaryocyte-macrophage were found during culture. This phenomenon was in part due to the fact that a significant reduction of apoptotic fractions was found in the CD34(+) cells, which were cultured on the adherent monolayer for up to 5 weeks. To gather quantitative data on the number of endothelial cells derived from a given number of CD34 cells, we performed limiting dilution assay by using Poisson distribution: the number of tested cells (linear scale) producing a 37% negative culture (logarithmic scale) is the number of cells containing one endothelial cell. By this method, one endothelial cell may be found from 314 CD34(+) cells after 5 weeks of culture. These results suggest that the UCB CD34(+) cell fraction contains endothelial cell precursors, establishing the hematopoietic microenvironment and providing the beneficial effects through downregulating apoptosis on UCB expansion protocols. These observations may provide insight for future cellular therapy or graft engineering.