Two cases of Mycoplasma pneumoniae pneumonia with A2063G mutation in the 23S rRNA gene in siblings.

We describe 2 cases of pneumonia caused by the same macrolide-resistant Mycoplasma pneumoniae in siblings. M. pneumoniae was identified using real-time PCR. Direct sequence analysis of the 23S rRNA gene revealed a point mutation in V domain (A2063G) of the 23S rRNA gene.

Elevated Serum Levels of IL-21 in Kawasaki Disease.

PURPOSE: The serum level of immunoglobulin (Ig)E has been reported to be elevated in patients with Kawasaki disease (KD). We investigated whether interleukin (IL)-21, rather than IL-4, could be related to elevated serum levels of IgE in KD. METHODS: Sera from 48 patients with KD and 12 controls with high fever were collected to determine the level of IgE using an immunoassay system and the levels of IL-4 and IL-21 were determined using enzyme-linked immunosorbent assay kits. RESULTS: The median IL-21 level of KD patients was significantly elevated, at 499.5 pg/mL (range: <62.5-1,544 pg/mL), whereas that of controls was <62.5 pg/mL (<62.5-825 pg/mL; P<0.001). The median IL-4 level of KD patients was not elevated (4.0 pg/mL; 2.1-7.6 pg/mL). The median level of total IgE in KD patients was 58.0 IU/mL (5-1,109 IU/mL). No statistically significant correlation was found between IL-21 and total IgE levels (Spearman's R=0.2; P=0.19). CONCLUSIONS: Patients with KD have elevated levels of IL-21 in the serum. IL-21 may play a role in the pathogenesis of KD.

Evaluation of new hemagglutinin-based rapid antigen test for influenza A pandemic (H1N1) 2009.

BACKGROUND: A new rapid antigen test (RAT), based on hemagglutinin, was developed for the improvement of influenza A pandemic (H1N1) 2009 detection. OBJECTIVE: To evaluate the performance of the new RAT for the diagnosis of influenza A pandemic (H1N1) 2009. STUDY DESIGN: The new RAT included 2009 H1N1 hemagglutinin-based band and influenza A and influenza B nucleoprotein-based bands. During the period from November 24, 2009 to December 14, 2009, 948 patients underwent the new RAT and real-time reverse transcriptase polymerase chain reaction (rRT-PCR) at the same time. The result of the new RAT was compared with that of rRT-PCR, and the results of hemagglutinin-based and nucleoprotein-based antigen tests were compared. RESULT: Among the 260 patients confirmed by rRT-PCR, 153 (58.8%) were positive in the nucleoprotein-based antigen test, and 182 (70.0%) were positive in the hemagglutinin-based antigen test. These results show that the new hemagglutinin-based antigen test was more sensitive than the nucleoprotein-based antigen test for the detection of influenza A pandemic (H1N1) 2009 (p<0.001, the McNemar test). CONCLUSION: The new hemagglutinin-based antigen test improved the sensitivity of diagnosis for influenza A pandemic (H1N1) 2009 and it might be helpful for the diagnosis of influenza A pandemic (H1N1) 2009.

Identification of adenovirus, influenza virus, parainfluenza virus, and respiratory syncytial virus by two kinds of multiplex polymerase chain reaction (PCR) and a shell vial culture in pediatric patients with viral pneumonia.

PURPOSE: Early identification of causative agents in lower respiratory infection of pediatric patients can reduce morbidity and prevent an overuse of antimicrobials. Two kinds of multiplex polymerase chain reaction (PCR) and a commercial shell vial viral culture were performed to identify causative agents in pediatric patients. MATERIALS AND METHODS: Nasopharyngeal aspirates of 220 children diagnosed with viral pneumonia were obtained. Two kinds of multiplex PCR (Seeplex(TM) RV detection kit, and Labopass(TM) RV detection kit), and a shell vial culture by R-Mix were performed. RESULTS: Positive samples from 220 total samples by two multiplex PCRs were 52.7% and 46.4%, respectively. We also cultured 103 samples that showed positive results of the adenovirus, influenza virus, parainfluenza virus, and respiratory syncytial virus (RSV) by two multiplex PCR. The RSV was most frequently detected in 53.0% (Seeplex) and 51.7% (Labopass) of patients. The detection rate of adenovirus (AdV) was 10.3% and 12.1%, influenza virus (IFV) A and B was 12.5% and 3.4%, and parainfluenza virus (PIFV) 1, 2, and 3 were 2.9% and 2.6%. Shell vial cultures showed concordant results with each multiplex PCR by 96.1% and 77.7%, respectively. Sequencing results were 90% consistent with multiplex PCR. CONCLUSION: Multiplex PCR showed more positivity than the shell vial culture and it can be an effective primary test. Other complementary efforts such as viral cultures and sequencing analysis could be considered, according to clinical and laboratory conditions.

Predicting factors for refractory kawasaki disease.

BACKGROUND AND OBJECTIVES: About 10-15% of Kawasaki disease (KD) is refractory to intravenous immunoglobulin (IVIG) therapy. This study was designed to investigate the predicting factors for refractory KD. SUBJECTS AND METHODS: We reviewed retrospectively the clinical records of 77 patients with typical KD admitted at Wonju Christian Hospital from January, 2005, to December, 2008. The variance of laboratory and demographic parameters between the IVIG-responsive group and IVIG-resistant group were analyzed. Thirteen patients with urinary tract infections were randomly collected as a febrile control group. RESULTS: Among 77 patients diagnosed with complete KD, 13 patients (16.9%) were IVIG-resistant. The febrile period and hospital days were significantly longer in the IVIG-resistant group than IVIG-responsive group (p<0.001, p=0.002). Serum levels of albumin and sodium were significantly lower in the IVIG-resistant group (p=0.025). The Kobayashi score could differentiate these two groups (p=0.015). Fewer lymphocytes was observed during the subacute phase in the IVIG-resistant group (p=0.032). Coronary arterial dilatations (CADs) were observed in 10.9% (7/64) of IVIG-responders and 38.5% (5/13) of IVIG-resistant patients (p=0.038). CONCLUSION: The percentage of neutrophils and lymphocytes in patients with KD, in addition to known risk factors for refractory KD, may help predict IVIG-resistance in patients with KD.

Relationship between gallbladder distension and lipid profiles in kawasaki disease.

BACKGROUND AND OBJECTIVES: Kawasaki disease (KD) is an acute systemic vasculitis in children which causes coronary arterial dilatation (CAD) and gallbladder distension (GBD). There is a dearth of investigating the relationship between the severity of KD and GBD with lipid profiles. SUBJECTS AND METHODS: A total of 80 patients with 'complete KD' who were diagnosed from January 2005 to May 2009 was enrolled in this study. Serum cholesterol {total, high density lipoprotein-cholesterol (HDL-C) and low density lipoprotein-cholesterol (LDL-C)}, triglyceride (TG), complete blood count, inflammation markers {erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)} were measured at the time of admission during febrile period. Echocardiography and abdominal sonogram were performed in all patients to determine CAD and gallbladder size. According to GBD, patients with KD were classified as patients with GBD and patients without GBD. Between two groups, demographic and clinical data were analyzed. RESULTS: The serum level of LDL-C was significantly lower in patients with GBD (p=0.03) compared with patients without GBD or febrile control. There was no significant difference in inflammatory indices between patients with GBD and patients without GBD. GBD was not significant risk factor of CAD in this study (odds ratio=2.0, 95% confidence interval=0.82-5.3, p=0.16). CONCLUSION: This is the first study that highlights the relationship between the GBD and lipid metabolism in patients with KD. This study provides clinical insights about potential mechanism underpinning the relationship between the GBD and lipid metabolism.

Programmed death-1 (PD-1) gene polymorphisms lodged in the genetic predispositions of Kawasaki Disease.

The purpose of this study is to investigate the association of programmed death-1 gene (PD-1) polymorphisms with genetic predispositions to Kawasaki disease (KD). A total of 73 patients with KD and 100 healthy controls were enrolled from 2007 to 2008. Two single nucleotide polymorphisms of the PD-1 gene, rs41386349 and rs2227981, were analyzed. Higher T allele frequency of rs41386349 was found in the patient group than the control group (p = 0.007, odds ratio (OR) = 1.9, 95% CI = 1.2-2.9). PD-1 rs2227981 polymorphism was not significant in patients with KD comparing with the control group (p = 0.4, OR = 1.2 (0.8-1.9)). Furthermore, no difference of PD-1 polymorphisms between patients with coronary artery dilatation (CAD) and those without CAD was found. Our data support the possibility that PD-1 gene polymorphism may be related with the genetic susceptibility of KD in Korean population.

The role of a whole blood interferon-gamma assay for the detection of latent tuberculosis infection in Bacille Calmette-Guérin vaccinated children.

The tuberculin skin test (TST) has limitations in children who are under the Bacille Calmette-Guérin (BCG) effect. Our aim was to evaluate the QuantiFERON-TB Gold In-Tube (QFT-G IT) blood test for Mycobacterium tuberculosis infection in children and to compare results with those of the TST. QFT-G IT and TST data were collected from 227 children between 0 and 15 years of age, split into 4 risk groups. Forty-two children were close contacts, 29 were casual contacts, and 65 were controls. The QFT-G IT positivity rates were 19% (8/42), 6.9% (2/29), and 1.5% (1/65), with a significantly higher rate for the close contacts over the controls (P < 0.05). The high specificity of the QFT-G IT assay and the association of positive results with increasing risk of infection in our study suggest it has major benefits over the TST as a screening test for latent infection with M. tuberculosis in BCG-vaccinated children.

Low-dose methotrexate therapy for intravenous immunoglobulin-resistant Kawasaki disease.

PURPOSE: The aim of this study was to evaluate the efficacy of low-dose oral methotrexate (MTX) as a treatment for patients with Kawasaki disease (KD) which was resistant to intravenous immunoglobulin (IVIG). PATIENTS AND METHODS: The patients who had persistent or recrudescent fever after treatment with IVIG were subsequently treated with low-dose oral MTX [10mg/body surface area (BSA)] once weekly. RESULTS: Seventeen patients developed persistent or recrudescent fever after treatment of KD with IVIG and were consequently given MTX. The proportion of children with coronary artery lesions (CALs) was 76%. The median value of maximum body temperatures decreased significantly within 24 hours of MTX therapy (38.6 degrees C vs. 37.0 degrees C, p < 0.001). The median CRP (C-reactive protein) level was found to be significantly lower 1 week after administering the first dose of MTX (8.9mg/dL vs. 1.2mg/dL, p < 0.001). The median duration of fever before MTX treatment was shorter in CALs (-) group than in CALs (+) group (7 days vs. 10 days, p = 0.023). No adverse effects of MTX were observed. CONCLUSION: MTX treatment for IVIG-resistant KD resulted in quick resolution of fever and rapid improvement of inflammation markers without causing any adverse effects. MTX therapy should further be assessed in a multicenter, placebo-blinded trial to evaluate whether it also improves coronary artery outcome.

Analysis of clinical presentations of Bruton disease: a review of 20 years of accumulated data from pediatric patients at Severance Hospital.

PURPOSE: X-linked agammaglobulinemia (XLA) is a humoral immunodeficiency disease caused by a mutation in the Bruton tyrosine kinase (BTK) gene resulting in defective B cell differentiation. Because it is a relatively rare disorder, it is difficult for clinicians to have a comprehensive understanding of XLA due to a lack of exposure to the disease. Clinical presentations of patients with XLA were analyzed and discussed to improve care plans. MATERIALS AND METHODS: During a 20 year period, from January 1987 to June 2006, a total of 19 patients were diagnosed as XLA in the Department of Pediatrics at Severance Hospital, Seoul, Korea. A retrospective analysis of the clinical presentations of those patients was performed. RESULTS: The mean age of the XLA patients included in the study was 4.89 years, with a range of 6 months to 13 years. Twelve patients were diagnosed before age 5, while the other 7 patients were diagnosed after age 5. Recurrent infections observed in the patients included pneumonia, acute otitis media, septic arthritis, skin infection, sepsis, sinusitis, acute gastroenteritis, cervical lymphadenitis, epididymitis, meningitis, osteomyelitis, urinary tract infection and encephalitis. Frequency of admissions was variable from 0 to 12 times, depending on the time at which immunoglobulin therapy was started. Six cases had family histories positive for XLA. BTK gene mutations were found in 8 cases. CONCLUSION: The overall prognosis of XLA is good as long as patients are diagnosed and treated early with regular intra venous gamma globulin therapy before the sequelae of recurrent infections appear.