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

There have been some cases where abnormal histopathologic findings could not be found in the kidney could even with proper specimen collection through percutaneous renal biopsy (PRB) in accordance with its indication. We analyzed the incidence and clinical outcomes of children who showed normal histopathological findings in their PRBs. Methods: The medical records of 552 pediatric subjects who underwent PRB between 2005 and 2016 were reviewed. Twenty-six subjects were excluded because allograft biopsy was performed in nine subjects, and the age at biopsy was greater than 18 years in 17 subjects. Finally, 526 subjects were enrolled in this study. Results: Of the 526 pediatric patients, 32 (6.1%) showed no histopathological abnormalities in their PRBs. The male-to-female ratio of the patients was 1.9:1, and the mean ages at the first visit and at biopsy were 10.6 ± 4.1 and 11.4 ± 3.8 years, respectively. In accordance with the biopsy indications, recurrent gross hematuria showed the highest incidence rate, but combined hematuria and proteinuria had the lowest incidence rate regarding normal renal histopathology among all the subjects. At a mean follow-up of 35.5 ± 23.6 months, urinary abnormalities had improved in more than 50% of the subjects with normal renal histopathology, and none of the patients showed progression to end-stage renal disease or required rebiopsy due to symptom worsening during the follow-up period. Conclusion: The clinical outcomes of children with normal PRB histopathologic findings are generally good. Further studies to evaluate their long-term outcomes are needed.

Background and Objectives: Kawasaki disease (KD) is an acute systemic vasculitis that affects the coronary arteries. Abnormal immune reactions are thought to contribute to disease pathogenesis. The effect of immunoglobulin (Ig) isotype (IgG, IgA, IgM, and IgE) on inflammatory data and clinical outcomes of patients with KD was examined. Methods: Ig levels in 241 patients with KD were measured during the acute, subacute, convalescent, and normal phases of the disease. Results: Compared with reference Ig values, IgG, IgA, and IgM levels were significantly higher in the subacute phase, while IgE levels were elevated in 73.9% (178/241) of patients with KD in all clinical phases. However, high IgE levels were not associated with clinical outcomes, including intravenous immunoglobulin unresponsiveness and coronary artery lesions (CALs).Significantly more CALs were observed in the high IgA group than in the normal IgA group (44.7% vs. 20.8%, respectively; p<0.01). In addition, IgA levels in the acute phase (p=0.038) were 2.2-fold higher, and those in the subacute phase were 1.7-fold higher (p <0.001), in the CAL group than in the non-CAL group. IgA concentrations increased along with the size of the coronary artery aneurysm (p <0.001). Furthermore, there was a strong correlation between IgA levels and CAL size (r=0.435, p<0.001), with a high odds ratio of 2.58 (p=0.022). Conclusions High IgA levels in patients with KD are prognostic for the risk of CALs.

Background and Objectives: Kawasaki disease (KD) is an acute systemic vasculitis that affects the coronary arteries. Abnormal immune reactions are thought to contribute to disease pathogenesis. The effect of immunoglobulin (Ig) isotype (IgG, IgA, IgM, and IgE) on inflammatory data and clinical outcomes of patients with KD was examined. Methods: Ig levels in 241 patients with KD were measured during the acute, subacute, convalescent, and normal phases of the disease. Results: Compared with reference Ig values, IgG, IgA, and IgM levels were significantly higher in the subacute phase, while IgE levels were elevated in 73.9% (178/241) of patients with KD in all clinical phases. However, high IgE levels were not associated with clinical outcomes, including intravenous immunoglobulin unresponsiveness and coronary artery lesions (CALs).Significantly more CALs were observed in the high IgA group than in the normal IgA group (44.7% vs. 20.8%, respectively; p<0.01). In addition, IgA levels in the acute phase (p=0.038) were 2.2-fold higher, and those in the subacute phase were 1.7-fold higher (p <0.001), in the CAL group than in the non-CAL group. IgA concentrations increased along with the size of the coronary artery aneurysm (p <0.001). Furthermore, there was a strong correlation between IgA levels and CAL size (r=0.435, p<0.001), with a high odds ratio of 2.58 (p=0.022). Conclusions High IgA levels in patients with KD are prognostic for the risk of CALs.

Purpose: Alport syndrome (AS) is one of the most common inherited renal diseases caused due to mutations of genes encoding specific proteins of the type IV collagen family, and its major clinical manifestations include progressive renal failure, sensorineural deafness, and ocular abnormalities. We investigated the clinical characteristics and long-term prognosis of AS in Korean pediatric and adult populations. Methods: We conducted a retrospective review of medical records of 33 children and adults who had been diagnosed or treated with AS from 1985 to 2019. Results: The mean age of the 33 patients diagnosed with AS was 16.2±13.6 years, and the male-to-female ratio was 2:1. At the first visit, recurrent gross hematuria was the most common initial symptom. In 10 of 33 patients (30.3%), sensorineural hearing loss (SNHL) was diagnosed, but none had ophthalmic problems. Moreover, 11 of 33 patients (33.3%) had advanced to end-stage renal disease (ESRD), and a significant difference was observed in the age of the patients who progressed to ESRD based on the presence or absence of SNHL (P =0.035). Conclusion SNHL in AS can be an important prognostic factor for long-term deterioration of renal function. Further investigation is required to confirm the clinical course and the genetic characteristics of AS in Korea through prospective national cohort studies.

PURPOSE: Nutritional markers, such as total protein, albumin, and vitamin D have been reportedly associated with neonatal outcomes. This study aimed to assess the correlation between nutritional markers at birth and the need for respiratory support on the first day of life. METHODS: This retrospective study included 94 newborns admitted to the neonatal intensive care unit of Kyungpook National University Children's Hospital between March and December 2017. We measured levels of nutritional markers, including serum total protein, albumin, ferritin, 25-hydroxyvitamin D (25-OHD), and prealbumin, from cord blood or blood sample within 24 hours after birth. Respiratory support was defined as the use of nasal continuous positive airway pressure, humidified high-flow nasal cannula, or mechanical ventilation on the first day of life. RESULTS: The mean gestational age and birth weight were 36.6±2.3 weeks and 2,714±575 g, respectively. Serum total protein, albumin, prealbumin, and ferritin levels at birth were significantly correlated with gestational age and birth weight. Total protein, albumin, ferritin, and 25-OHD levels were not correlated with the time to recover birth weight after adjusting for gestational age. Moreover, prealbumin levels at birth were significantly lower in small-for-gestational-age infants than in appropriate-for-gestational-age infants. The need for respiratory support on the first day of life decreased 0.058- and 0.001-fold for every 1 g/dL increase in serum total protein (95% confidence interval [CI], 0.004 to 0.833; P=0.036) and albumin (95% CI, 0.000 to 0.136; P=0.009) levels, respectively. CONCLUSION: Nutritional status at birth could be associated with the need for respiratory support on the first day of life, regardless of the Apgar score.
Apgar Score ; Birth Weight ; Catheters ; Continuous Positive Airway Pressure ; Ferritins ; Fetal Blood ; Gestational Age ; Gyeongsangbuk-do ; Humans ; Infant ; Infant, Newborn ; Intensive Care, Neonatal ; Nutritional Status ; Parturition ; Prealbumin ; Respiration, Artificial ; Respiratory Insufficiency ; Retrospective Studies ; Vitamin D

PURPOSE: Croup is known to have epidemics in seasonal and biennial trends, and to be strongly associated with epidemics of parainfluenza virus. However, seasonal and annual epidemics of croup have not been clearly reported in Korea. This study aimed to examine the seasonal/annual patterns and etiologies of childhood croup in Korea during a consecutive 6-year period. METHODS: Pediatric croup data were collected from 23 centers in Korea from 1 January 2010 to 31 December 2015. Electronic medical records, including multiplex reverse transcription polymerase chain reaction (RT-PCR) results, demographics and clinical information were cross-sectionally reviewed and analyzed. RESULTS: Overall, 2,598 childhood croup patients requiring hospitalization were identified during the study period. Among them, a total of 927 who underwent RT-PCR were included in the analysis. Males (61.5%) predominated, and most (63.0%) of them were younger than 2 years of age (median, 19 months; interquartile range, 11–31 months). Peak hospitalization occurred in 2010 and 2012 in even-numbered years, and parainfluenza virus (PIV, 39.7%) was the most common cause of childhood croup requiring hospitalization, followed by respiratory syncytial virus (14.9%), human rhinovirus (12.5%), Mycoplasma pneumonaie (10.6%), and human coronavirus (7.3%). CONCLUSION: It is concluded that croup hospitalization has a biennial pattern in even-numbered years. PIV may be the most common cause of childhood croup; however, croup epidemics could be attributed to other viruses.
Child ; Coronavirus ; Croup ; Demography ; Electronic Health Records ; Hospitalization ; Humans ; Korea ; Male ; Mycoplasma ; Paramyxoviridae Infections ; Polymerase Chain Reaction ; Respiratory Syncytial Viruses ; Retrospective Studies ; Reverse Transcription ; Rhinovirus ; Seasons

Kawasaki disease (KD) is an acute febrile vasculitis predominately affecting infants and children. The dominant incidence age of KD is from 6 months to 5 years of age, and the incidence is unusual in those younger than 6 months and older than 5 years of age. We tried to identify genetic variants specifically associated with KD in patients younger than 6 months or older than 5 years of age. We performed an age-stratified genome-wide association study using the Illumina HumanOmni1-Quad BeadChip data (296 cases vs. 1,000 controls) and a replication study (1,360 cases vs. 3,553 controls) in the Korean population. Among 26 candidate single nucleotide polymorphisms (SNPs) tested in replication study, only a rare nonsynonymous SNP (rs4365796: c.1106C>T, p.Thr369Met) in the lymphoid enhancer binding factor 1 (LEF1) gene was very significantly associated with KD in patients younger than 6 months of age (odds ratio [OR], 3.07; p(combined) = 1.10 × 10⁻⁵), whereas no association of the same SNP was observed in any other age group of KD patients. The same SNP (rs4365796) in the LEF1 gene showed the same direction of risk effect in Japanese KD patients younger than 6 months of age, although the effect was not statistically significant (OR, 1.42; p = 0.397). This result indicates that the LEF1 gene may play an important role as a susceptibility gene specifically affecting KD patients younger than 6 months of age.
Asian Continental Ancestry Group ; Child ; Genome-Wide Association Study ; Humans ; Incidence ; Infant ; Lymphoid Enhancer-Binding Factor 1 ; Mucocutaneous Lymph Node Syndrome* ; Polymorphism, Single Nucleotide ; Vasculitis

PURPOSE: The incidence of inflammatory bowel disease (IBD) is rapidly increasing, and several reports have described the renal complications of IBD. We sought to evaluate the clinical manifestations of renal complications in children with IBD in order to enable early detection and prompt treatment of the complications. METHODS: We retrospectively reviewed the medical records of 456 children and adolescents aged < 20 years who had been diagnosed with IBD since 2000. We analyzed patient age, sex, medication use, IBD disease activity, and clinical manifestations of renal symptoms. RESULTS: Our study comprising 456 children with IBD included 299 boys (65.6%) and 157 girls (34.4%). The study included 346 children with Crohn disease and 110 children with ulcerative colitis. The incidence of kidney-related symptoms was 14.7%, which was significantly higher than that in normal children. We observed 26 children (38.8%) with isolated hematuria, 30 children (44.8%) with isolated proteinuria, and 11 children (16.4%) with hematuria and concomitant proteinuria. A renal biopsy was performed in 7 children. Histopathological examination revealed immunoglobulin A nephropathy in 5 children (71.4%). All children presented with mild disease and well-controlled disease activity of IBD. CONCLUSION: Children with IBD are more likely to show kidney-related symptoms than healthy children and adolescents are. Therefore, regular screening of urine and evaluation of renal function in such children are necessary for early detection of renal complications.
Adolescent* ; Biopsy ; Child* ; Colitis, Ulcerative ; Crohn Disease ; Female ; Glomerulonephritis, IGA ; Hematuria ; Humans ; Incidence ; Inflammatory Bowel Diseases* ; Kidney ; Mass Screening ; Medical Records ; Proteinuria ; Retrospective Studies

BACKGROUND: Various systemic agents have been assessed for the treatment of alopecia areata (AA); however, there is a paucity of comparative studies. OBJECTIVE: To assess and compare cyclosporine and betamethasone minipulse therapy as treatments for AA with regard to effectiveness and safety. METHODS: Data were collected from 88 patients who received at least 3 months of oral cyclosporine (n=51) or betamethasone minipulse therapy (n=37) for AA. Patients with ≥50% of terminal hair regrowth in the alopecic area were considered responders. RESULTS: The responder of the cyclosporine group was 54.9% and that of the betamethasone minipulse group was 37.8%. In the cyclosporine group, patients with mild AA were found to respond better to the treatment. Based on the patient self-assessments, 70.6% of patients in the cyclosporine group and 43.2% of patients in the betamethasone minipulse group rated their hair regrowth as excellent or good. Side effects were less frequent in the cyclosporine group. CONCLUSION: Oral cyclosporine appeared to be superior to betamethasone minipulse therapy in terms of treatment effectiveness and safety.
Alopecia Areata* ; Alopecia* ; Betamethasone* ; Cyclosporine* ; Hair ; Humans ; Pulse Therapy, Drug ; Self-Assessment ; Treatment Outcome