Comparison of COVID-19-associated multisystem inflammatory syndrome in children (MIS-C) and Kawasaki disease shock syndrome: case reports and literature review

Multisystem inflammatory syndrome in children (MIS-C) is a serious post-infectious complication of COVID-19 characterized by hyperinflammation and multi-organ dysfunction including shock. Shock is also seen in a severe form of Kawasaki disease (KD) called KD shock syndrome (KDSS). Here, we present one MIS-C and one KDSS case and compare similarities and differences between them. Both MIS-C (case 1) and KDSS (case 2) showed hyperinflammation, KD-related features, gastrointestinal problems, hypotension, and coagulopathy. The extent of systemic inflammation and organ dysfunction was more severe in KDSS than in MIS-C. Case 1 was diagnosed as MIS-C because SARS-CoV-2 was confirmed, and case 2 was diagnosed as KDSS because no pathogen was identified in microbiological studies. We believe that the most important difference between MIS-C and KDSS was whether SARS-CoV-2 was identified as an infectious trigger. Organ dysfunction is a hallmark of MIS-C and KDSS, but not KD, so MIS-C shares more clinical phenotypes with KDSS than with KD. Comparison of MIS-C and KDSS will be an interesting and important topic in the field of KD-like hyperinflammatory disease research.

Ischemic Vaso-occlusive Retinopathy as Initial Presentation in Pediatric Systemic Lupus Erythematosus: A Case Report

Ischemic vaso-occlusive retinopathy as an initial manifestation is rare in pediatric systemic lupus erythematosus (pSLE). A 13-year-old girl presented with two months’ history of papules and crusts with fatigue, weight loss, and abrupt hair loss. Pancytopenia and findings compatible with SLE, including positive direct Coombs’ test, antinuclear antibody (Ab), anti-double stranded DNA Ab, anti-Smith Ab, anti-ribonucleoprotein Ab, lupus anticoagulant, anti-β2 glycoprotein Immunoglobulin G, and anti-cardiolipin Ab, were detected. Bi-nasal hemianopsia was detected. Initial visual acuity was hand motion in the right eye and 15/20 in the left. Fundoscopy showed massive exudation around the optic disc with macular edema, vascular sheathing with perivascular hemorrhage in the whole retina, and ghost vessels in the peripheral retina. Intravitreal triamcinolone injection and dexamethasone implant injection were administered. Visual symptoms improved but did not recover. Methylprednisolone therapy and photocoagulation improved visual acuity and fever. Early intervention for retinopathy in pSLE can help prevent vision-loss.

Changes in the Incidence of Intussusception and Infectious Diseases After the COVID-19 Pandemic in Korea

Background@#Intussusception refers to the invagination of a part of the intestine into itself. The exact cause for this condition is unknown in most cases. The active implementation of coronavirus disease 2019 (COVID-19) infection control guidelines has reduced the spread of COVID-19 and the incidence of other infectious diseases in children. The current study aimed to identify changes in pediatric intussusception and infectious diseases after the implementation of infection control guidelines and confirm the association between intussusception and contagious diseases. @*Methods@#We analyzed the electronic medical records of pediatric patients diagnosed with intussusception from seven hospitals in Korea between January 2017 and December 2020.We used open data from the Korea Disease Control and Prevention Agency to investigate changes in infectious diseases over the same period. @*Results@#Altogether, we evaluated 390 children with intussusception. There was a statistically significant decrease in the incidence of monthly visits with intussusception in the COVID-19 period group (9.0 vs. 3.5, P < 0.001). When the monthly incidence of infectious diseases was compared between the pre-COVID-19 and the COVID-19 periods, a statistically significant decrease in respiratory viruses (7979.0 vs. 815.2, P < 0.001), enterovirus infection (262.2 vs. 6.6, P < 0.001), and viral enteritis (916.2 vs. 197.8, P< 0.001) were confirmed in the COVID-19 period. Through interrupted time series analysis, it was confirmed that the incidence of intussusception and viral infectious diseases have drastically decreased since March 2020, when COVID-19 infection control guidelines were actively implemented. @*Conclusion@#We confirmed that implementing infection control guidelines during the COVID-19 pandemic resulted in a decrease in intussusception and viral infectious diseases.Through this result, it was possible to indirectly confirm the existing hypothesis that viral infections play a significant role in the pathophysiologic mechanism of intussusception.

A Boy with X-Linked Inhibitor of Apoptosis Protein (XIAP) Deficiency as the Initial Presentation of Pure Red Cell Aplasia / 임상소아혈액종양

X-linked inhibitor of apoptosis protein (XIAP) deficiency is a rare immunodeficiency disorder. A 13-month-old boy was diagnosed with pure red cell aplasia (PRCA) and treated with steroid and cyclosporine. Bone marrow showed diminished erythroid precursors, and positive results for Parvovirus B19 and Cytomegalovirus (CMV) infection. A genetic study of Diamond-Blackfan anemia was negative. Five months later, he was admitted due to fever and lymphadenopathy. PCR showed still positive for the Parvovirus, CMV, and Epstein-Barr virus (EBV). He was diagnosed with diffuse large B-cell lymphoma that was positive for EBV. The patient received chemotherapy with R-CHOP, and achieved complete remission. Immunoglobulin (Ig) levels were within an age-matched normal range until the completion of chemotherapy. Subsequently, he was admitted nine times due to recurrent pneumonia and acute otitis media between two and eight years old. We reanalyzed the Ig levels and lymphocyte subsets: IgG, IgA, and IgM were 30 mg/dL, below 1.0 mg/dL, and 36 mg/dL, respectively. Lymphocyte subsets showed nearly absent CD19 (+) cells, but T- and NK cell counts were within normal ranges. A genetic study showed a hemizygous inframe deletion mutation in exon 4 of the IAP gene without the SH2D1A mutation, consistent with a XIAP deficiency. Therefore, he was diagnosed with XIAP deficiency. Genetic analysis of his mother, aunt and elder sister showed that they were carriers of the same gene mutation. He receives intravenous Ig regularly with follow-up, and still requires a low dose steroid to maintain hemoglobin level. We report XIAP deficiency as initial presentation of PRCA.

Impending Cardiac Tamponade and Hemorrhagic Pleural Effusion as Initial Presentations of Incomplete Kawasaki Disease: A Case Report

Kawasaki disease (KD) is an acute febrile illness that is characterized by systemic inflammation usually involving medium-sized arteries and multiple organs during the acute febrile phase, leading to associated clinical findings. The diagnosis is based on the principal clinical findings including fever, extremity changes, rash, conjunctivitis, oral changes, and cervical lymphadenopathy. However, KD diagnosis is sometimes overlooked or delayed because other systemic organ manifestations may predominate in acute phase of KD. As a cardiovascular manifestation, an acute pericarditis usually shows a small pericardial effusion, but large pericardial effusion showing clinical signs of cardiac tamponade is very rare. Here, we described a case of incomplete KD presenting with impending cardiac tamponade, and recurrent fever and pleural effusion.

Deep Neck Inflammation: Probable Kawasaki Disease in Korean Children

Objectives@#. Deep neck infections (DNIs) can cause life-threatening complications, and prompt diagnosis and management are necessary. Kawasaki disease (KD) may be accompanied by deep neck inflammation; making it difficult to distinguish from DNIs. This study was performed to evaluate clinical features and outcomes of children with parapharyngeal and retropharyngeal inflammation. @*Methods@#. Medical records of the children diagnosed with parapharyngeal and retropharyngeal cellulitis or abscess using cervical computed tomography (CT) between 2013 and 2017 were retrospectively reviewed. @*Results@#. A total of 47 children were diagnosed with parapharyngeal and retropharyngeal inflammation. Eleven (23.4%) of them were eventually diagnosed with KD, and 36 (76.6%) were diagnosed with DNIs. There were no significantly different clinical and laboratory characteristics on admission between children diagnosed with KD and DNIs; however, significantly more children with KD were febrile for ≥3 days after admission compared to those with DNIs (P=0.009). Deep neck abscesses on CT were observed in 16 children with DNIs (44.4%) and in no child with KD (P=0.009). Among the 36 children with DNIs, 30 (83.3%) were cured with antibiotic therapy only. @*Conclusion@#. A quarter of children presenting with deep neck inflammation were diagnosed with KD. KD should be considered in children showing deep neck inflammation unresponsive to empirical antibiotic therapy after 3 days, especially in those presenting with deep neck cellulitis rather than deep neck abscess.

A Boy with Chronic Active EBV Infection Presented as Mosquito Bite Hypersensitivity Progressed to Fatal Hemophagocytic Lymphohistiocytosis due to NK Cell Neoplasm / 임상소아혈액종양

Chronic active Epstein-Barr virus (CAEBV) infection is characterized by recurrent infectious mononucleosis (IM)-like symptoms and an unusual pattern of anti-EBV antibodies. We report a boy with CAEBV who progressed to aggressive hemophagocytic lymphohistiocytosis (HLH) with NK cell neoplasm. A 19-year-old adolescent boy was admitted with fever and a history of recurrent IM-like symptoms following mosquito bites since the age of 6 years. His condition was diagnosed as CAEBV with atypical lymphocytosis and an unusual pattern of anti-EBV antibodies. His symptoms subsided during treatment with steroids and cyclosporine, although the EBV genome load kept increasing for several years. He was re-admitted after follow-up loss for 8 years, and his clinical and laboratory findings confirmed HLH and high titer of the EBV genome. Bone marrow analysis with flow cytometry showed hemophagocytosis with compatible NK cell neoplasm. He rapidly progressed to pulmonary infection and expired soon after. We conclude that hematopoietic stem cell transplantation may be a potential therapeutic modality for treating CAEBV before serious EBV manifestations.

The Current and Future State of Academic Medicine in Korea: Education, Research, and Patient Care / 의학교육논단

Academic medicine is built from a foundation of education, research, and patient care. Since good patient care results from the application of medical research and continuous education, these three components cannot be separated for medical development to occur. In Korea, many obstacles hinder the achievement of academic medicine, such as an inefficient medical delivery system, limitations of primary care, low insurance prices, and no long-term health care plan. Medical education has changed to outcome-based education, but presented temporal integration status. Governance of healthcare research is not centralized, and Korea is awarded relatively fewer grants than other countries. Medical professors have reached a burnout state due to patient care responsibilities in addition to research and education duties. Many medical systems, including the medical delivery system and insurance problems, may contribute to distrust between doctors and patients. The government is not involved in a long-term health care policy. The multitude of factors mentioned here are hindering the achievement of academic medicine in Korea.

Seroprevalence of Hepatitis A Virus in Pediatric Patients with Hematologic Malignancies after Chemotherapy and Hematopoietic Cell Transplantation

This retrospective study was performed to determine the seroprevalence of hepatitis A virus (HAV) in children and adolescents with hematologic malignancies after the completion of chemotherapy and hematopoietic cell transplantation (HCT). Of 97 enrolled patients, 60 (61.9%) were seropositive for HAV. The seroprevalences in patients undergoing chemotherapy and HCT were 60.3% (41/68) and 65.5% (19/29), respectively (P = 0.628). No significant factors associated with seropositivity for HAV after chemotherapy and HCT were identified. Anti-HAV tests and HAV re-vaccinations can be considered in children and adolescents with underlying hematologic malignancies after chemotherapy and HCT based on the anti-HAV results.

Monogenic Autoimmune Diseases

Monogenic autoimmune diseases (AD) present as lupus-like clinical manifestations with recurrent fever or various vasculopathies. Recurrent fever with an elevation of acute phase reactants and various skin lesions are similar in monogenic AD and autoinflammatory disease. The molecular pathogenesis of adult systemic erythematosus can be understood through monogenic AD based on gene defects: complement, apoptosis, interferonopathy via nucleic acid sensing, tolerance, rasopathies, and others. Skin vasculopathy with chilblains and livedo reticularis, interstitial lung disease, and panniculitis are common occurrences in type I interferonopathy. Some syndromes have been reported to present with autoimmune inflammation and the general clinical findings, including cerebral calcification. Various clinical manifestations in monogenic AD present in accordance with the gene loss- or gain-of-function mutations involved. The monogenic AD for the early onset of more severe lupus-like symptoms or vasculopathy needs to be considered. Furthermore, clinical trials were conducted via targeted therapy for related molecular pathways, because conventional treatments were not effective in managing monogenic AD.

Allogeneic hematopoietic stem cell transplantation in congenital hemoglobinopathies with myeloablative conditioning and rabbit anti-thymocyte globulin

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative therapy for β-thalassemia major (TM) and sickle cell disease (SCD) in children. Graft-versus-host disease (GVHD) and treatment-related mortality (TRM) remain significant challenges to improving survival after HSCT. Here, we analyzed the outcome of TM and SCD patients, who received allogeneic HSCT with myeloablative conditioning at our institution. METHODS: Twenty-two patients (15 TM, 7 SCD), with a median age of 9 years (range, 1.6–16.9), underwent allogeneic HSCT using busulfan, cyclophosphamide and rabbit anti-thymocyte globulin-based conditioning. Cells were derived from either the bone marrow (8 patients), or peripheral blood stem cells (14 patients). The majority of patients received HSCT from a matched sibling donor (N=18). GVHD prophylaxis included cyclosporine and short course methotrexate. RESULTS: All patients achieved donor engraftment. Two SCD patients died from TRM-related grade IV gut GVHD (N=1) or severe bronchiolitis obliterans (BO) (N=1). Cumulative incidence of acute and chronic GVHD was 36.4% and 32.7%, respectively. Veno-occlusive disease (VOD) occurred in 8 patients (36.4%), but resolved in all instances. Epstein-Barr virus (EBV)-related post-transplantation lymphoproliferative disease (PTLD) occurred in 1 patient. The overall survival (OS) was 90.9% (TM 100%, SCD 71.4%), with all patients achieving transfusion independence, while 8 achieved complete donor chimerism. CONCLUSION: Busulfan, cyclophosphamide, and ATG-based conditioning for HSCT of TM and SCD patients did not result in graft failure, although modifications may be required to reduce VOD incidence. Further changes to donor type and cell source prioritization are necessary to minimize TRM and morbidity caused by GVHD.

Treatment and response of autoimmune cytopenia occurring after allogeneic hematopoietic cell transplantation in children

BACKGROUND: Autoimmune cytopenia (AIC) is a rare complication of allogeneic hematopoietic cell transplantation (HCT). In this study, we reviewed the diagnosis, treatment and response to therapy for pediatric patients with post-HCT AIC at our institution. METHODS: Of the 292 allogeneic HCTs performed from January, 2011 to December, 2015 at the Department of Pediatrics, The Catholic University of Korea, seven were complicated by post-HCT AIC, resulting in an incidence of 2.4%. RESULTS: All seven patients with post-HCT AIC had received unrelated donor transplant. Six of seven patients had a major donor-recipient blood type mismatch. The subtypes of AIC were as follows: immune thrombocytopenia (ITP) 2, autoimmune hemolytic anemia (AIHA) 2, Evans syndrome 3. Median time from HCT to AIC diagnosis was 3.6 months. All but one patient responded to first line therapy of steroid±intravenous immunoglobulin (IVIG), but none achieved complete response (CR) with this treatment. After a median duration of treatment of 15.3 months, two patients with ITP achieved CR and five had partial response (PR) of AIC. Five patients were treated with rituximab, resulting in the following response: 2 CR, 2 PR, 1 no response (NR). Median time to response to rituximab was 26 days from first infusion. All patients are alive without event. CONCLUSION: Post-HCT AIC is a rare complication that may not resolve despite prolonged therapy. Rapid initiation of second line agents including but not limited to B cell depleting treatment should be considered for those that fail to achieve CR with first line therapy.

Community-acquired Escherichia coli Enteritis in Korean Children: The Clinical Application of a Stool Polymerase Chain Reaction Assay

BACKGROUND: Although Escherichia coli is a common cause of bacterial enteritis in Korea, reports on community-acquired E. coli enteritis in Korean children are scarce. This study aimed to determine the clinical characteristics and pathotype distribution of community-acquired E. coli enteritis diagnosed by a multiplex polymerase chain reaction (PCR) assay in Korean children. MATERIALS AND METHODS: The medical records of children aged 18 years or less who were diagnosed with acute gastroenteritis by the attending physician between 2013 and 2016 were retrospectively reviewed. The clinical characteristics of children diagnosed with E. coli enteritis were investigated and compared with those diagnosed with Salmonella enteritis. E. coli and Salmonella infections were diagnosed by a stool PCR assay. RESULTS: Among 279 children, in whom PCR assays for E. coli and Salmonella spp. were performed, Salmonella enteritis and E. coli enteritis were diagnosed in 43 (15.4%) and 39 (14.0%) children, respectively. Among the 39 children with E. coli enteritis, enteropathogenic E. coli (n=21, 53.8%) and enteroaggregative E. coli (n=15, 38.4%) were the most common causative agents. Empirical antibiotics were administered to 33 (84.6%) children. A total of 31 (79.5%) children developed fever, and 25 (80.6%) of them had the fever for 3 days or less, which resolved a median of 1 day (range 0-3 days) after hospitalization. The most frequent gastrointestinal symptom was diarrhea (n=36, 92.3%). Significantly more children with E. coli enteritis were aged 2 years or less as compared with those with Salmonella enteritis (41.0% vs. 21.9%, P = 0.021). Children with Salmonella enteritis more frequently complained of fever (97.7% vs. 79.5%, P = 0.012), abdominal pain (90.7% vs. 64.1%, P = 0.004), and hematochezia (46.5% vs. 10.3%, P < 0.001) than those with E. coli enteritis. Erythrocyte sedimentation rate and C-reactive protein levels were significantly higher in children with Salmonella enteritis than those with E. coli enteritis (P < 0.001). CONCLUSION: Enteropathogenic E. coli was the most frequent pathotype in Korean children with E. coli enteritis that caused mild clinical symptoms. A stool PCR assay for E. coli may be useful for epidemiological purpose and for an early diagnosis of E. coli enteritis.

Outcome and Prognostic Factors for ETV6/RUNX1 Positive Pediatric Acute Lymphoblastic Leukemia Treated at a Single Institution in Korea / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: ETV6/RUNX1 (+) acute lymphoblastic leukemia (ALL), which is the most common genetic subtype of pediatric ALL, has a favorable prognosis. In this study, we analyzed the outcome of ETV6/RUNX1 (+) ALL patients treated at our institution with the aim of identifying significant prognostic variables. MATERIALS AND METHODS: Sixty-three patients were diagnosed with ETV6/RUNX1 (+) ALL from 2005 to 2011. Prognostic variables studied included minimal residual disease (MRD) as detected by ETV6/RUNX1 (+) fusion, and the presence of additional cytogenetic abnormalities. RESULTS: The 5-year event-free survival was 84.1±4.6%, with 10 patients relapsing at a median of 28.3 months from diagnosis for a 5-year cumulative incidence of relapse of 15.9±4.6%. Multivariate analysis revealed that the presence MRD, as detected by real-time quantitative-polymerase chain reaction or fluorescence in situ hybridization for ETV6/RUNX1 fusion at end of remission induction, and the presence of additional structural abnormalities of 12p (translocations or inversions) negatively affected outcome. Despite treatment such as allogeneic hematopoietic cell transplantation, eight of the 10 relapsed patients died from disease progression for overall survival of 82.5±6.9%. CONCLUSION: ETV6/RUNX1 (+) ALL may be heterogeneous in terms of prognosis, and variables such as MRD at end ofremission induction or additional structural abnormalities of 12p could define a subset of patients who are likely to have poor outcome.

Increase in Antibiotic-Resistant Gram-Negative Bacterial Infections in Febrile Neutropenic Children

BACKGROUND: The incidence of bacteremia caused by Gram-negative bacteria has increased recently in febrile neutropenic patients with the increase of antibiotic-resistant Gram-negative bacterial infections. This study aimed to identify the distribution of causative bacteria and the proportion of antibiotic-resistant bacteria in bacteremia diagnosed in febrile neutropenic children. MATERIALS AND METHODS: The medical records of febrile neutropenic children diagnosed with bacteremia between 2010 and 2014 were retrospectively reviewed. The causative bacteria and proportion of antibiotic-resistant bacteria were investigated and compared yearly during the study period. The clinical impact of antibiotic-resistant bacterial infections was also determined. RESULTS: A total of 336 bacteremia episodes were identified. During the entire study period, 181 (53.9%) and 155 (46.1%) episodes were caused by Gram-negative and Gram-positive bacteria, respectively. Viridans streptococci (25.9%), Klebsiella spp. (16.7%), and Escherichia coli (16.4%) were the most frequent causative bacteria. The overall distribution of causative bacteria was not significantly different annually. Antibiotic-resistant bacteria were identified in 85 (25.3%) episodes, and the proportion of antibiotic-resistant bacteria was not significantly different annually. Extended-spectrum β-lactamase-producing E. coli and Klebsiella spp. were most common among antibiotic-resistant Gram-negative bacteria, and they accounted for 30.6% (n = 34) of the identified E. coli and K. pneumoniae. Methicillin-resistant coagulase-negative staphylococci were most common among antibiotic-resistant Gram-positive bacteria, and it accounted for 88.5% (n = 23) of the identified coagulase-negative staphylococci. Antibiotic-resistant bacterial infections, especially antibiotic-resistant Gram-negative bacterial infections, caused significantly higher mortality due to bacteremia compared with non-antibiotic-resistant bacterial infections (P <0.001). CONCLUSION: Recently, Gram-negative bacteria caused more bacteremia cases than Gram-positive bacteria in febrile neutropenic children, and antibiotic-resistant Gram-negative bacterial infections increased. Antibiotic-resistant bacterial infections caused poorer prognosis compared with non-antibiotic-resistant bacterial infections, and therefore, continuous surveillance for changing epidemiology of antibiotic-resistant bacterial infections and their clinical impact is necessary.

Clinical Impact of Mixed Respiratory Viral Infection in Children with Adenoviral Infection

BACKGROUND: Although adenovirus (ADV) infection occurs steadily all year round in Korea and the identification of respiratory viral coinfections has been increasing following the introduction of multiplex real-time polymerase chain reaction tests, the clinical impact of viral coinfection in children with ADV infection has rarely been reported. MATERIALS AND METHODS: Medical records of children diagnosed with ADV infection were retrospectively reviewed. The enrolled children were divided into two groups based on the identified respiratory viruses: ADV group and coinfection group. Clinical and laboratory parameters were compared between the two groups. RESULTS: In total, 105 children (60 males and 45 females) with a median age of 29 months (range: 0-131 months) diagnosed with an ADV infection were enrolled. Fever (99.0%) was by far the most frequent symptom, followed by respiratory (82.9%), and gastrointestinal (22.9%) symptoms. Upper and lower respiratory tract infections were diagnosed in 56 (53.3%), and 32 (30.5%) children, respectively. Five (4.8%) children received oxygen therapy, and no child died due to ADV infection. Coinfection was diagnosed in 32 (30.5%) children, with rhinovirus (46.9%), and respiratory syncytial virus (21.9%) being the most frequent. The proportions of children younger than 24 months (P <0.001), with underlying medical conditions (P = 0.020), and diagnosed with lower respiratory tract infection (P = 0.011) were significantly higher in the coinfection group than in the ADV group. In a multivariate analysis, only the younger age was significantly associated with coinfection (P <0.001). Although more children in the coinfection group received oxygen therapy (P = 0.029), the duration of fever and hospitalization was not significantly different between the two groups. CONCLUSION: Respiratory viral coinfection with ADV occurred more frequently in children younger than 24 months of age compared with children aged 24 months or older. Respiratory viral coinfection may increase the severity of ADV infection, however, appropriate therapy prevented prolonged hospitalization and poor prognosis due to coinfection.

Recurrent macrophage activation syndrome since toddler age in an adolescent boy with HLA B27 positive juvenile ankylosing spondylitis / 소아과

Recurrent macrophage activation syndrome (MAS) is very rare. We present the case of an adolescent boy with human leukocyte antigen (HLA) B27-positive ankylosing spondylitis (AS), who experienced episodes of recurrent MAS since he was a toddler. A 16-year-old boy was admitted because of remittent fever with pancytopenia and splenomegaly after surgical intervention for an intractable perianal abscess. He had been diagnosed with hemophagocytic lymphohistiocytosis (HLH) 4 different times, which was well controlled with intravenous immunoglobulin and steroids since the age of 3. We were unable to identify the cause for the HLH. He remained symptom-free until the development of back pain and right ankle joint pain with swelling at 15 years of age. He was diagnosed with HLA B27-positive AS with bilateral active sacroiliitis. He showed symptom aggravation despite taking naproxen and methotrexate, and the symptoms improved with etanercept. On admission, his laboratory data showed leukopenia with high ferritin and triglyceride levels. Bone marrow biopsy examination showed histiocytic hyperplasia with hemophagocytosis. There was no evidence of infection. He received naproxen alone, and his symptoms and laboratory data improved without any other immunomodulatory medications. Genetic study revealed no primary HLH or inflammasome abnormalities. In this case, underlying autoimmune disease should have been considered as the cause of recurrent MAS in the young patient once primary HLH was excluded.

Clinical characteristics and outcomes of varicella zoster virus infection in children with hematologic malignancies in the acyclovir era

BACKGROUND: Although intravenous acyclovir therapy is recommended for varicella zoster virus (VZV) infection in immunocompromised children, the clinical characteristics and outcomes of VZV infection in the acyclovir era have rarely been reported. METHODS: The medical records of children diagnosed with varicella or herpes zoster virus, who had underlying hematologic malignancies, were retrospectively reviewed, and the clinical characteristics and outcomes of VZV infection were evaluated. RESULTS: Seventy-six episodes of VZV infection (herpes zoster in 57 and varicella in 19) were identified in 73 children. The median age of children with VZV infection was 11 years (range, 1-17), and 35 (46.1%) episodes occurred in boys. Acute lymphoblastic leukemia was the most common underlying malignancy (57.9%), and 90.8% of the episodes occurred during complete remission of the underlying malignancy. Acyclovir was administered for a median of 10 days (range, 4-97). Severe VZV infection occurred in 16 (21.1%) episodes. Although the finding was not statistically significant, a previous history of hematopoietic cell transplantation (HCT) appeared to be associated with the development of more severe episodes of herpes zoster (P=0.075). CONCLUSION: Clinical characteristics of VZV infection in immunocompromised children were not significantly different from those without it, and clinical outcomes improved after the introduction of acyclovir therapy. However, risk factors for severe VZV infection require further investigation in a larger population and a prospective setting.

Clinical Features and Prognosis of Invasive Pulmonary Aspergillosis in Korean Children with Hematologic/Oncologic Diseases

Invasive pulmonary aspergillosis (IPA) is the most frequent form of invasive fungal diseases in immunocompromised patients. However, there are only a few studies on IPA in immunocompromised children in Korea. This study was designed to characterize IPA in Korean children with hematologic/oncologic diseases. Medical records of children with hematologic/oncologic diseases receiving antifungal therapy were reviewed. The enrolled children were divided into the IPA group (proven and probable IPA) and non-IPA group, and the clinical characteristics and prognosis were compared between the two groups. During the study period, 265 courses of antifungal therapy were administered to 166 children. Among them, two (0.8%) episodes of proven IPA, 35 (13.2%) of probable IPA, and 52 (19.6%) of possible IPA were diagnosed. More children in the IPA group suffered from neutropenia lasting for more than two weeks (51.4% vs. 21.9%, P<0.001) and showed halo signs on the chest computed tomography (78.4% vs. 40.7%, P<0.001) than in the non-IPA group. No other clinical factors showed significant differences between the two groups. Amphotericin B deoxycholate was administered as a first line antifungal agent in 33 (89.2%) IPA group episodes, and eventually voriconazole was administered in 27 (73.0%) episodes. Ten (27.0%) children in the IPA group died within 12 weeks of antifungal therapy. In conclusion, early use of chest computed tomography to identify halo signs in immunocompromised children who are expected to have prolonged neutropenia can be helpful for early diagnosis of IPA and improving prognosis of children with IPA.

Hepatic veno-occlusive disease may develop in secondary iron overloaded mice after allogeneic hematopoietic stem cell transplantation with total body irradiation

BACKGROUND: The outcome of hematopoietic stem cell transplantation (HSCT) is poor in patients with secondary iron overload (SIO). We evaluated the relationship between SIO and veno-occlusive disease (VOD) in an animal model with radiation for HSCT. METHODS: We used a 6-week-old female BDF1 (H-2b/d) and a male C57/BL6 (H-2b) as recipient and donor, respectively. Recipient mice were injected intraperitoneally with 10 mg of iron dextran (cumulative doses of 50 mg, 100 mg, and 200 mg). All mice received total body irradiation for HSCT. We obtained peripheral blood for alanine transaminase (ALT) and liver for pathologic findings, lipid hyperoxide (LH) as reactive oxygen species (ROS), and liver iron content (LIC) on post-HSCT day 1 and day 7. The VOD score was assessed by pathologic findings. RESULTS: ALT levels increased depending on cumulative iron dose, with significant differences between days 1 and 7 for mice loaded with 200 mg of iron (P<0.01). LH levels significantly increased in mice loaded with 200 mg of iron compared to those in other groups (P<0.01). For mice loaded with 100 mg of iron, the LH level depended on the radiation dose (P<0.01). There was a statistically significant relationship among ALT, LH, and LIC parameters (P<0.05). Pathologic scores for VOD correlated with LIC (P<0.01). CONCLUSION: Livers with SIO showed high ROS levels depending on cumulative iron dose, and correlations with elevated liver enzyme and LIC. The pathologic score for VOD was associated with the LIC. Our results suggest that SIO may induce VOD after HSCT with irradiation.