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.

Juvenile Dermatomyositis

Juvenile dermatomyositis (JDM) is a systemic capillary vasculopathy. Patients present with proximal muscle weakness, raised muscle enzymes, and pathognomic skin rashes such as heliotrope rash, Gottron’s papules. Main complications are calcinosis, lipodystrophy, osteoporosis. Complement-mediated damage of vessels is a major mechanism. Magnetic resonance imaging is currently widely used to diagnosis of JDM. The goals of treatment are to control inflammatory myositis and prevent disease complication. Early, aggressive treatment of JDM associated with a better prognosis. High-dose corticosteroids in combination with methotrexate is the mainstay of treatment. The course of JDM is variable.

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.

Clinical implications in laboratory parameter values in acute Kawasaki disease for early diagnosis and proper treatment / 소아과

PURPOSE: This study aimed to analyse laboratory values according to fever duration, and evaluate the relationship across these values during the acute phase of Kawasaki disease (KD) to aid in the early diagnosis for early-presenting KD and incomplete KD patients. METHODS: Clinical and laboratory data of patients with KD (n=615) were evaluated according to duration of fever at presentation, and were compared between patients with and without coronary artery lesions (CALs). For evaluation of the relationships across laboratory indices, patients with a fever duration of 5 days or 6 days were used (n=204). RESULTS: The mean fever duration was 6.6±2.3 days, and the proportions of patients with CALs was 19.3% (n=114). C-reactive proteins (CRPs) and neutrophil differential values were highest and hemoglobin, albumin, and lymphocyte differential values were lowest in the 6-day group. Patients with CALs had longer total fever duration, higher CRP and neutrophil differential values and lower hemoglobin and albumin values compared to patients without CALs. CRP, albumin, neutrophil differential, and hemoglobin values at the peak inflammation stage of KD showed positive or negative correlations each other. CONCLUSION: The severity of systemic inflammation in KD was reflected in the laboratory values including CRP, neutrophil differential, albumin, and hemoglobin. Observing changes in these laboratory parameters by repeated examinations prior to the peak of inflammation in acute KD may aid in diagnosis of early-presenting KD patients.

Clinical implications of DMSA Scan in Childhood Acute Pyelonephritis

PURPOSE: This study aimed to evaluate the relationships between 99mTecnicium-dimercaptosuccinic acid (DMSA) scan findings and clinical parameters including age and fever duration. METHODS: The positive rates for abnormal DMSA scans were analyzed according to the age of patients, fever duration prior to admission, and total fever duration. DMSA scan findings were divided into 3 categories: single defect, multifocal defects, and discrepant defects. We evaluated the detection rates of vesicoureteral reflux according to DMSA scan lesions. RESULTS: Among a total 320 cases, 141 (44.1%) had abnormal DMSA scans. The infant group (0-1 year of age) had a shorter total fever duration, and a lower C-reactive protein (CRP) value and DMSA positive rate (39.8% vs. 60.6%, P=0.002) compared to children group (2-15 years of age). Patients with abnormal scans had a longer total fever duration and higher CRP compared to those with normal scans. The positivity rate of abnormal scans did not differ between the patients with a short fever duration prior to admission of ≤2 days and those with longer fever duration of ≥3 days. However, patients with longer total fever duration had a higher rate of abnormal DMSA scans (P=0.02). Among cases with a single defect, multifocal defects, and discrepant defects, vesicoureteral reflux was observed in 22.4%, 60% and 70.6% of cases, respectively (P=0.004). CONCLUSION: Although DMSA scan has limitations in early diagnosis, DMSA scan findings may aid in the prediction of the severity of systemic inflammation and detection of vesicoureteral reflux.

Clinical implications of DMSA Scan in Childhood Acute Pyelonephritis

PURPOSE: This study aimed to evaluate the relationships between 99mTecnicium-dimercaptosuccinic acid (DMSA) scan findings and clinical parameters including age and fever duration. METHODS: The positive rates for abnormal DMSA scans were analyzed according to the age of patients, fever duration prior to admission, and total fever duration. DMSA scan findings were divided into 3 categories: single defect, multifocal defects, and discrepant defects. We evaluated the detection rates of vesicoureteral reflux according to DMSA scan lesions. RESULTS: Among a total 320 cases, 141 (44.1%) had abnormal DMSA scans. The infant group (0-1 year of age) had a shorter total fever duration, and a lower C-reactive protein (CRP) value and DMSA positive rate (39.8% vs. 60.6%, P=0.002) compared to children group (2-15 years of age). Patients with abnormal scans had a longer total fever duration and higher CRP compared to those with normal scans. The positivity rate of abnormal scans did not differ between the patients with a short fever duration prior to admission of ≤2 days and those with longer fever duration of ≥3 days. However, patients with longer total fever duration had a higher rate of abnormal DMSA scans (P=0.02). Among cases with a single defect, multifocal defects, and discrepant defects, vesicoureteral reflux was observed in 22.4%, 60% and 70.6% of cases, respectively (P=0.004). CONCLUSION: Although DMSA scan has limitations in early diagnosis, DMSA scan findings may aid in the prediction of the severity of systemic inflammation and detection of vesicoureteral reflux.

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.

Changes in Acute Poststreptococcal Glomerulonephritis: An Observation Study at a Single Korean Hospital Over Two Decades

PURPOSE: The incidence of acute poststreptococcal glomerulonephritis (APSGN) in Korea has changed. This study aimed to evaluate the epidemiological and clinical changes of APSGN observed in a single Korean institution over two decades. METHODS: We retrospectively analyzed the data of 99 children (0-15 years of age) who were admitted to our institution with APSGN between 1987 and 2013. The patients were selected based on the depression of serum complement 3 (C3, 250 IU/dL) as evidence of previous streptococcal infection. RESULTS: In the 99 patients, the mean age was 8.3 +/- 2.7 years, and the male-tofemale ratio was 2.2:1 (66:30). The annual number of cases fluctuated markedly, and most cases were observed during the late autumn and winter months. However, there have been few cases reported in the past 5 years. Clinical manifestations at presentation, including hypertension and generalized oedema, and the duration of hospitalization were higher and longer in patients admitted during the first half of the study period than during the most recent half-period, suggesting a more severe clinical course in the former group. CONCLUSIONS: APSGN has become a rare disease in Korea with a trend towards a less severe clinical course. This finding suggests that the prevalence of infection-related immune-mediated diseases could change over-time, together with environmental and possibly pathogen-host relationship changes.

Detection of Rotavirus Genotypes in Korea 5 Years after the Introduction of Rotavirus Vaccines

Rotavirus (RV) is one of the most important viral etiologic agents of acute gastroenteritis (AGE) in children. Although effective RV vaccines (RVVs) are now used worldwide, novel genotypes and outbreaks resulting from rare genotype combinations have emerged. This study documented RV genotypes in a Korean population of children with AGE 5 yr after the introduction of RVV and assessed potential genotype differences based on vaccination status or vaccine type. Children less than 5-yr-old diagnosed with AGE between October 2012 and September 2013 admitted to 9 medical institutions from 8 provinces in Korea were prospectively enrolled. Stool samples were tested for RV by enzyme immunoassay and genotyped by multiplex reverse-transcription polymerase chain reaction. In 346 patients, 114 (32.9%) were RV-positive. Among them, 87 (76.3%) patients were infected with RV alone. Eighty-six of 114 RV-positive stool samples were successfully genotyped, and their combinations of genotypes were G1P[8] (36, 41.9%), G2P[4] (12, 14.0%), and G3P[8] (6, 7.0%). RV was detected in 27.8% of patients in the vaccinated group and 39.8% in the unvaccinated group (P=0.035). Vaccination history was available for 67 of 86 cases with successfully genotyped RV-positive stool samples; RotaTeq (20, 29.9%), Rotarix (7, 10.4%), unvaccinated (40, 59.7%). The incidence of RV AGE is lower in the RV-vaccinated group compared to the unvaccinated group with no evidence of substitution with unusual genotype combinations.

Epidemiological comparison of three Mycoplasma pneumoniae pneumonia epidemics in a single hospital over 10 years / 소아과

PURPOSE: Mycoplasma pneumoniae (MP) pneumonia epidemics have occurred in 3- to 4-year cycles in Korea. We evaluated the epidemiologic characteristics of MP pneumonia in Daejeon, Korea, from 2003 to 2012. METHODS: We retrospectively analyzed 779 medical records of children (0-15 years of old) with MP pneumonia admitted to our institution and compared the data from 3 recent epidemics. RESULTS: In 779 patients, the mean age and male-to-female ratio were 5.0+/-2.2 years and 1:1, and most cases were observed in autumn. There were three epidemics during the study period, in 2003, 2006-2007, and 2011. In our comparison of the three epidemics, we found no differences in mean age, the male-to-female ratio, hospital stay, or the rate of seroconverters during hospitalization. All three epidemics began in early summer and peaked in September 2003 and 2011 and in October 2006 and then gradually decreased until the next year's spring season, although the 2006 epidemic extended further into 2007. The peak age groups in the children in 2003 and 2006 were 3-6 year-olds (57.5% and 56%, respectively), but in the 2011 epidemic, the peak group was 1-4 year-olds (46.5%). The proportion of the 10 years of age group was 5.2%, 13.8%, and 14.8% of total patients, respectively. CONCLUSION: MP pneumonia outbreaks occurred every 3-4 years. The pattern of 3 recent epidemics was similar in demographic characteristics and seasonality with some variations in each outbreak.

Early Additional Immune-Modulators for Mycoplasma pneumoniae Pneumonia in Children: An Observation Study

BACKGROUND: Mycoplasma pneumoniae (MP) pneumonia is a self-limiting disease, but some patients complain of progressive pneumonia, despite of appropriate antibiotic treatment. We aimed to introduce the role of immune-modulators (corticosteroid and/or intravenous immunoglobulin, IVIG) treatment for childhood MP pneumonia based on previous our experiences. MATERIALS AND METHODS: A retrospective case series analysis for 183 children with MP pneumonia was performed. MP pneumonia patients were diagnosed by two Immunoglobulin M (IgM) tests: the micro-particle agglutination method (> or =1:40) and the cold agglutination test (> or =1:4), and were examined twice at the initial admission and at discharge. Among 183 MP pneumonia patients, 90 patients with persistent fever for over 48 hours after admission or those with severe respiratory symptoms and signs received additional prednisolone (82 patients, 1 mg/kg/day) or intravenous methylprednisolone (8 patients, 5-10 mg/kg/day) with antibiotics. Four patients with aggravated clinical symptoms and chest radiographic findings after corticosteroid treatment received IVIG (1 g/kg/day, 1-2 doses). RESULTS: Mean age of 183 patients was 5.5 +/- 3.2 years (6 months-15 years), and the male: female ratio was 1.1:1 (96:87). Fifty-seven patients (31%) were seroconverters and 126 seropositive patients showed increased diagnostic IgM antibody titres during admission (over 4 folds). The majority of the patients who received corticosteroids (86/90 cases) showed rapid defervescence within 48 hours with improved clinical symptoms, regardless of the used antibiotics. Also, 4 patients who received additional IVIG improved both clinically and radiographically within 2 days without adverse reaction. CONCLUSIONS: In the era of macrolide-resistant MP strains, early additional immune-modulator therapy with antibiotics might prevent from the disease progression and reduce the disease morbidity without adverse reaction.

Outbreaks of mumps: an observational study over two decades in a single hospital in Korea / 소아과

PURPOSE: The introduction of the mumps vaccine has dramatically reduced the number of mumps cases, but outbreaks have recently occurred among highly vaccinated populations in developed countries. Epidemiological and clinical characteristics of patients with mumps admitted between 1989 and 2012 in a single hospital in Korea are described in the present study. METHODS: We retrospectively evaluated inpatients with mumps between 1989 and 2012 and outpatients and inpatients with mumps in 2011-2012. RESULTS: A total of 152 patients with mumps were admitted between 1989 and 2012, and 163 patients were recorded in 2011-2012. The highest number of admitted cases occurred in 1998 and 2012 (35 and 34 cases, respectively). Among the patients admitted in 2011-2012, the highest frequency was observed among people aged 15-19 years, and low frequency was observed in those aged 20 years, compatible to the city data and national data. In patients admitted to our department in 1998 (35 cases) and in 2010-2012 (27 cases), there were significant differences in the mean age and the rate of secondary measles-mumps-rubella (MMR) vaccination, but had similar clinical features, including complications, except aseptic meningitis. Antimumps immunoglobulin (Ig) G was positive in 83% and 100%, and IgM was positive in 67% and 41%, respectively, in the two periods. CONCLUSION: In Korea, recent mumps outbreaks have occurred mainly among secondary school students who received two doses of the MMR vaccine. The vaccinees might have a modified immune reaction to viral insults, manifesting modified epidemiological and clinical features.

Comparison among Known Severity Scoring Scales in the Evaluation of Acute Gastroenteritis in Children / 소아감염

PURPOSE: This study aimed to evaluate the disease severity of children suffering from gastroenteritis using different scales. The results are compared and subsequently classified on the basis of the type of virus causing the disease in order to investigate the differences in clinical characteristics and disease severity according to pathogen. METHOD: This study was conducted prospectively with patients under 5 years of age diagnosed with acute gastroenteritis and hospitalized at 9 medical institutions in 8 regions across the Republic of Korea. Disease severity was evaluated using the Vesikari Scale, the Clark Scale, and the modified Flores Scale. Fecal samples collected from patients were used to detect rotavirus and enteric adenovirus by enzyme immunoassay, and for RT-PCR of norovirus, astrovirus, and sapovirus. RESULTS: There were a total of 214 patients with a male : female ratio of 1.58 : 1, of which 35 were under the age of 6 months (16.4%), 105 were aged 6-23 months (49.1%), and 74 were aged 24-59 months (34.5%). The rate of concordance between the Vesikari and Clark Scales was 0.521 (P<0.001) and, in severe cases, the Vesikari Scale was 60.7% and Clark Scale was 2.3%, indicating that the Clark Scale was stricter in the evaluation of severe cases. CONCLUSIONS: In children with gastroenteritis, there were differences in disease severity based on the scale used. Therefore, to achieve consistent results among researchers, either only a single scale or a measure of all scales should be used to determine disease severity.

Evaluation of Immunogenicity and Safety of the New Tetanus-Reduced Diphtheria (Td) Vaccines (GC1107) in Healthy Korean Adolescents: A Phase II, Double-Blind, Randomized, Multicenter Clinical Trial

This phase II clinical trial was conducted to compare the immunogenicity and safety of a newly developed tetanus-reduced diphtheria (Td) vaccine (GC1107-T5.0 and GC1107-T7.5) and control vaccine. This study was also performed to select the proper dose of tetanus toxoid in the new Td vaccines. Healthy adolescents aged between 11 and 12 yr participated in this study. A total of 130 subjects (44 GC1107-T5.0, 42 GC1107-T7.5 and 44 control vaccine) completed a single dose of vaccination. Blood samples were collected from the subjects before and 4 weeks after the vaccination. In this study, all subjects (100%) in both GC1107-T5.0 and GC1107-T7.5 groups showed seroprotective antibody levels (> or = 0.1 U/mL) against diphtheria or tetanus toxoids. After the vaccination, the geometric mean titer (GMT) against diphtheria was significantly higher in Group GC1107-T5.0 (6.53) and GC1107-T7.5 (6.11) than in the control group (3.96). The GMT against tetanus was 18.6 in Group GC1107-T5.0, 19.94 in GC1107-T7.5 and 19.01 in the control group after the vaccination. In this study, the rates of local adverse reactions were 67.3% and 59.1% in GC1107-T5.0 and GC1107-7.5, respectively. No significant differences in the number of adverse reactions, prevalence and degree of severity of the solicited and unsolicited adverse reactions were observed among the three groups. Thus, both newly developed Td vaccines appear to be safe and show good immunogenicity. GC1107-T5.0, which contains relatively small amounts of tetanus toxoid, has been selected for a phase III clinical trial.

Prevalence of Primary Immunodeficiency in Korea

This study represents the first epidemiological study based on the national registry of primary immunodeficiencies (PID) in Korea. Patient data were collected from 23 major hospitals. A total of 152 patients with PID (under 19 yr of age), who were observed from 2001 to 2005, have been entered in this registry. The period prevalence of PID in Korea in 2005 is 11.25 per million children. The following frequencies were found: antibody deficiencies, 53.3% (n = 81), phagocytic disorders, 28.9% (n = 44); combined immunodeficiencies, 13.2% (n = 20); and T cell deficiencies, 4.6% (n = 7). Congenital agammaglobulinemia (n = 21) and selective IgA deficiency (n = 21) were the most frequently reported antibody deficiency. Other reported deficiencies were common variable immunodeficiencies (n = 16), X-linked agammaglobulinemia (n = 15), IgG subclass deficiency (n = 4). Phagocytic disorder was mostly chronic granulomatous disease. A small number of patients with Wiskott-Aldrich syndrome, hyper-IgE syndrome, and severe combined immunodeficiency were also registered. Overall, the most common first manifestation was pneumonia. This study provides data that permit a more accurate estimation PID patients in Korea.

Kawasaki Disease: Laboratory Findings and an Immunopathogenesis on the Premise of a "Protein Homeostasis System"

Kawasaki disease (KD) is a self-limited systemic inflammatory illness, and coronary artery lesions (CALs) are a major complication determining the prognosis of the disease. Epidemiologic studies in Asian children suggest that the etiologic agent(s) of KD may be associated with environmental changes. Laboratory findings are useful for the diagnosis of incomplete KD, and they can guide the next-step in treatment of initial intravenous immunoglobulin non-responders. CALs seem to develop in the early stages of the disease before a peak in inflammation. Therefore early treatment, before the peak in inflammation, is mandatory to reduce the risk of CAL progression and severity of CALs. The immunopathogenesis of KD is more likely that of acute rheumatic fever than scarlet fever. A hypothetical pathogenesis of KD is proposed under the premise of a "protein homeostasis system"; where innate and adaptive immune cells control pathogenic proteins that are toxic to host cells at a molecular level. After an infection of unknown KD pathogen(s), the pathogenic proteins produced from an unknown focus, spread and bind to endothelial cells of coronary arteries as main target cells. To control the action of pathogenic proteins and/or substances from the injured cells, immune cells are activated. Initially, non-specific T cells and non-specific antibodies are involved in this reaction, while hyperactivated immune cells produce various cytokines, leading to a cytokine imbalance associated with further endothelial cell injury. After the emergence of specific T cells and specific antibodies against the pathogenic proteins, tissue injury ceases and a repair reaction begins with the immune cells.

Limitation of Prediction on Intravenous Immunoglobulin Responsiveness in Kawasaki Disease / 소아감염

PURPOSE: We aimed to evaluate predictive parameters for non-response to intravenous immunoglobulin (IVIG) in patients with Kawasaki disease (KD) before IVIG use using two controls. METHODS: We evaluated 229 consecutive KD patients who were treated with 2 g/kg of IVIG at a single center. Those who had persistent fever >24 hours after IVIG infusion made up the 23 IVIG non-responders; the first control included a total 206 defervesced cases and the second control included 46 cases that were matched for age and pre-treatment fever duration to non-responders. RESULTS: Demographic and clinical characteristics were similar in IVIG non-responders and responders at presentation. As for laboratory findings, the neutrophil differential, CRP, AST, ALT, and LDH were higher, and lymphocyte differential, total protein, albumin, platelet count, and total cholesterol were significantly lower in IVIG non-responders compared to responders by univariate analysis in both study designs. However in multivariate analysis, non-responders showed a significantly higher neutrophil differential (cutoff value, >77%, sensitivity 68.4% and specificity 79.5%) and lower cholesterol (<124 mg/dL, sensitivity 79% and specificity 70.5%). Whereas plasma albumin (<3.6 g/dL, sensitivity 73.7% and specificity 60%) was the sole laboratory parameter of non-responders in the second study design. CONCLUSION: Severity of inflammation in KD was reflected by higher or lower laboratory values at presentation. Because the multivariate analysis for these indices may be influenced by some confounding factors, including the numbers of patients of different ages and fever duration, other assessment modalities are needed for KD patients with the greatest risk of coronary artery lesions.

Corticosteroid Treatment in Siblings Affected with Severe Mycoplasma pneumoniae Pneumonia

Numerous evidences support the pathogenesis that M. pneumoniae pneumonia is associated with cell-mediated immune reaction. We report 2 cases of severe M. pneumoniae pneumonia in previously healthy sisters, who were both admitted during an epidemic of M.pneumoniae pneumonia. The elder sister, who was 16 years old, was admitted with M. pneumoniae pneumonia. She showed no response to treatment with clarithromycin and levofloxacin, and eventually progressed to severe ARDS, requiring mechanical ventilation. After treatment with hydrocortisone (200 mg/day), there were rapid improvements in clinical manifestations and chest radiographic findings. The younger sister, who was 14 years old, was admitted 10 days later, presenting with fever but no pneumonic lesions on chest radiograph. Just like her sister, the infection showed no response to clarithromycin. Fever persisted and pneumonic consolidation with mild pleural effusion was noticed in the left lower lobe on the 5th hospital-day. After treatment with oral prednisolone (1 mg/kg), she showed rapid defervescence and on the 8th hospital day, no pneumonic lesions were detectable on chest radiograph. Given the fact that the pathogenesis of pneumonia and extrapulmonary manifestations in M. pneumoniae infection is immune-mediated, an immunosuppressive therapy would be validated for selected patients with M. pneumoniae infections.

Corticosteroid Treatment in Siblings Affected with Severe Mycoplasma pneumoniae Pneumonia

Numerous evidences support the pathogenesis that M. pneumoniae pneumonia is associated with cell-mediated immune reaction. We report 2 cases of severe M. pneumoniae pneumonia in previously healthy sisters, who were both admitted during an epidemic of M.pneumoniae pneumonia. The elder sister, who was 16 years old, was admitted with M. pneumoniae pneumonia. She showed no response to treatment with clarithromycin and levofloxacin, and eventually progressed to severe ARDS, requiring mechanical ventilation. After treatment with hydrocortisone (200 mg/day), there were rapid improvements in clinical manifestations and chest radiographic findings. The younger sister, who was 14 years old, was admitted 10 days later, presenting with fever but no pneumonic lesions on chest radiograph. Just like her sister, the infection showed no response to clarithromycin. Fever persisted and pneumonic consolidation with mild pleural effusion was noticed in the left lower lobe on the 5th hospital-day. After treatment with oral prednisolone (1 mg/kg), she showed rapid defervescence and on the 8th hospital day, no pneumonic lesions were detectable on chest radiograph. Given the fact that the pathogenesis of pneumonia and extrapulmonary manifestations in M. pneumoniae infection is immune-mediated, an immunosuppressive therapy would be validated for selected patients with M. pneumoniae infections.

The Change of Immunologic Parameters in Acute Poststreptococcal Glomerulonephritis

PURPOSE: This study was aimed to evaluate the changes of immunologic parameters during hospitalization, and the relationship between IgG and other laboratory or clinical indices in patients with acute poststreptococcal glomerulonephritis (APSGN). METHODS: We reviewed the medical charts of 36 children with APSGN who showed ASO titer >250 Todd U/L and C3125 mmHg), gross hematuria, and weight gain were observed in 27.8% (10/36), 80.1% (29/36), and 80% (24/30) of the patients, respectively. The mean IgG level was 1,432+/-322 mg/dL (1,025+/-234 mg/dL in control group, P8 years of age (15 cases) (-0.6% vs. -5.7%, P=0.01). The IgG and ASO levels did not change, but C3 (P=0.001) and IgM (P=0.02) levels increased during admission. CONCLUSION: Increased IgG and ASO levels in APSGN did not change, but C3 level increased during admission. IgG level was not correlated with other laboratory parameters (ASO and C3) and the severity of the disease. Younger children seem to have less severe clinical course compare to older children. With our hypothetic pathogenesis of APSGN, further studies are needed to resolve the pathogenesis of the disease including the increase of IgG.