Epidemiologic and Clinical Outcomes of Pediatric Renal Tumors in Korea: A Retrospective Analysis of The Korean Pediatric Hematology and Oncology Group (KPHOG) Data.

PURPOSE: Renal tumors account for approximately 7% of all childhood cancers. These include Wilms tumor (WT), clear cell sarcoma of the kidney (CCSK), malignant rhabdoid tumor of the kidney (MRTK), renal cell carcinoma (RCC), congenital mesoblastic nephroma (CMN) and other rare tumors. We investigated the epidemiology of pediatric renal tumors in Korea. MATERIALS AND METHODS: From January 2001 to December 2015, data of pediatric patients (0-18 years) newly-diagnosed with renal tumors at 26 hospitals were retrospectively analyzed. RESULTS: Among 439 patients (male, 240), the most common tumor was WT (n=342, 77.9%), followed by RCC (n=36, 8.2%), CCSK (n=24, 5.5%), MRTK (n=16, 3.6%), CMN (n=12, 2.7%), and others (n=9, 2.1%). Median age at diagnosis was 27.1 months (range 0-225.5) and median follow-up duration was 88.5 months (range 0-211.6). Overall, 32 patients died, of whom 17, 11, 1, and 3 died of relapse, progressive disease, second malignant neoplasm, and treatment-related mortality. Five-year overall survival and event free survival were 97.2% and 84.8% in WT, 90.6% and 82.1% in RCC, 81.1% and 63.6% in CCSK, 60.3% and 56.2% in MRTK, and 100% and 91.7% in CMN, respectively (p < 0.001). CONCLUSION: The pediatric renal tumor types in Korea are similar to those previously reported in other countries. WT accounted for a large proportion and survival was excellent. Non-Wilms renal tumors included a variety of tumors and showed inferior outcome, especially MRTK. Further efforts are necessary to optimize the treatment and analyze the genetic characteristics of pediatric renal tumors in Korea.

Usefulness of Routine Coagulation Tests in Healthy Children Undergoing Elective Minor Surgery: a 12-Year Retrospective Study.

BACKGROUND: Although routine coagulation tests, such as prothrombin time (PT) and activated partial thromboplastin time (aPTT) are performed before surgery to identify the risk of perioperative bleeding, bleeding complications are rare in minor surgeries, and false-positive results are often observed. Therefore, this study aimed to analyze the common causes of abnormal results of preoperative coagulation tests in previously healthy children undergoing elective minor surgery and determine the usefulness of performing these tests. Additionally, it aimed to identify the distribution of factor XII activity in children with prolonged aPTT. METHODS: The medical records of 363 pediatric patients aged 0 - 18 years, who were referred to the pediatric hematology-oncology department due to abnormal preoperative coagulation tests prior to undergoing minor surgery at the Kyung Hee University Medical Center between March 2008 and October 2020, were retrospectively review-ed. RESULTS: The majority of patients (n = 348, 96%) had prolonged aPTT, few (n = 29, 8%) had a prolonged PT international normalized ratio, and a small number (n = 14, 4%) had both prolonged PT and aPTT. On repeating the coagulation tests, 194 children showed persistent abnormal results. Of these, 184 patients underwent mixing tests, and 176 showed correction for factor deficiency (n = 26) and lupus anticoagulant positive (n = 14). Factor deficiencies included factor XII (n = 16), possibility of von Willebrand disease (vWD; n = 4), factor XI (n = 2), factor VIII (n = 1), factors IX and XII (n = 1), factor VII (n = 1), and factor V (n = 1). The severity of factor deficiency was mild (25 - 38%). One patient with factor VII deficiency received preoperative clotting factors but had postoperative bleeding requiring clotting factor replacement. Another patient with possible vWD received fresh frozen plasma after surgery and had mild symptoms. Linear regression showed no significant correlation between factor XII activity and aPTT in patients with prolonged aPTT (R2 = 0.0002, p = 0.84) or factor XII activity according to aPTT results in those with factor XII deficiency (R2 = 0.04749, p = 0.40). CONCLUSIONS: These results suggest that coagulation tests may be selectively performed in previously healthy children undergoing minor surgery with positive bleeding and/or family history. The distribution of factor XII should be investigated further.

Can we Predict the Clinical Course of Immune Thrombocytopenia in Children by The Mean Platelet Volume? A Preliminary Study.

BACKGROUND: Mean platelet volume (MPV) is considered a marker of platelet function and is known to increase in immune thrombocytopenia (ITP). We aimed to investigate the predictive value of MPV for predicting the clinical course of ITP in children. METHODS: We retrospectively analyzed children aged < 18 years with ITP (n = 36) and healthy controls (n = 36) from June 2010 to November 2018. The subjects were stratified into: (i) Healthy controls [group I, n = 36]; (ii) Newly diagnosed ITP (nITP) and persistent ITP (pITP) [group II, n = 24]; and (iii) Chronic ITP (cITP) [group III, n = 12]. Hematological indices including MPV were measured and compared between the three groups. RESULTS: The median MPV values at diagnosis in group I, II, and III were 7.20, 8.15, and 8.65 fL, respectively (p = 0.0004). Cutoff value of MPV at diagnosis differentiating group I from group II + III was 7.6 fL, and group II from group III was 8.7 fL. MPV change (ΔMPV after three months minus MPV at diagnosis) in children with nITP and pITP (n = 22) was greater than in those with cITP (n = 6) (-2.18 fL vs. 0.66 fL, p = 0.0059). CONCLUSIONS: This study revealed that group III had a higher MPV than group II at diagnosis. Therefore, an initial MPV value more than 8.7 fL may be used as a predictive factor for chronicity in children with ITP. The change in MPV over time as well as MPV at diagnosis, may be regarded as a prognostic marker to predict the course of ITP in children.

Rapid weight gain in early life is associated with severity of respiratory syncytial virus (RSV) bronchiolitis in children

Objectives This study aimed to investigate whether rapid weight gain in early life was associated with the severity of respiratory syncytial virus (RSV) bronchiolitis in children. Methods We retrospectively reviewed 190 patients (1–24 months) hospitalized for RSV bronchiolitis. Parameters of bronchiolitis severity were compared between rapid (change in weight z-score from birth >0.67, n = 65) and normal weight gain groups (n = 125). We assessed for correlations between bronchiolitis severity and weight gain. Linear regression was performed to predict for bronchiolitis severity based on weight gain, controlling for covariates. SPSS was used for statistical analyses. Results The rapid weight gain group had longer mean durations of tachypnea (2.3±2.0 vs. 1.7±1.8 days, P = 0.027), wheezing (3.2±2.5 vs. 1.6±1.8 days, P < 0.001), and chest retractions (1.5±2.2 vs. 0.6±1.3 days, P = 0.007). Correlations of weight gain with tachypnea (r = 0.146), wheezing (r = 0.279), and chest retractions (r = 0.179) were statistically significant. Weight gain predicted for tachypnea (B = 0.485, P = 0.013) and wheezing (B = 0.846, P = 0.001) durations after adjusting for covariates of severity (age, sex, current weight, RSV type, coinfection, recurrent bronchiolitis, hospital stay, fever, oxygen supplementation, maximal respiratory and heart rates, and laboratory indices). Conclusions Our findings suggest an association between weight gain and severity of RSV bronchiolitis in young children. Weight gain was significantly associated with the durations of tachypnea and wheezing. The trajectory of weight gain in early life may play a significant role in the clinical course of RSV bronchiolitis (AU)

Rapid weight gain in early life is associated with severity of respiratory syncytial virus (RSV) bronchiolitis in children.

OBJECTIVES: This study aimed to investigate whether rapid weight gain in early life was associated with the severity of respiratory syncytial virus (RSV) bronchiolitis in children. METHODS: We retrospectively reviewed 190 patients (1-24 months) hospitalized for RSV bronchiolitis. Parameters of bronchiolitis severity were compared between rapid (change in weight z-score from birth >0.67, n = 65) and normal weight gain groups (n = 125). We assessed for correlations between bronchiolitis severity and weight gain. Linear regression was performed to predict for bronchiolitis severity based on weight gain, controlling for covariates. SPSS was used for statistical analyses. RESULTS: The rapid weight gain group had longer mean durations of tachypnea (2.3±2.0 vs. 1.7±1.8 days, P = 0.027), wheezing (3.2±2.5 vs. 1.6±1.8 days, P < 0.001), and chest retractions (1.5±2.2 vs. 0.6±1.3 days, P = 0.007). Correlations of weight gain with tachypnea (r = 0.146), wheezing (r = 0.279), and chest retractions (r = 0.179) were statistically significant. Weight gain predicted for tachypnea (B = 0.485, P = 0.013) and wheezing (B = 0.846, P = 0.001) durations after adjusting for covariates of severity (age, sex, current weight, RSV type, coinfection, recurrent bronchiolitis, hospital stay, fever, oxygen supplementation, maximal respiratory and heart rates, and laboratory indices). CONCLUSIONS: Our findings suggest an association between weight gain and severity of RSV bronchiolitis in young children. Weight gain was significantly associated with the durations of tachypnea and wheezing. The trajectory of weight gain in early life may play a significant role in the clinical course of RSV bronchiolitis.

Epidemiology of Congenital Bleeding Disorders: a Nationwide Population-based Korean Study.

BACKGROUND: Except for data in the Korea Hemophilia Foundation Registry, little is known of the epidemiology of congenital bleeding disorders in Korea. METHODS: Data were obtained from the Korean Health Insurance Review and Assessment Service (HIRA) database. RESULTS: From 2010 to 2015, there were 2,029 patients with congenital bleeding disorders in the Korean HIRA database: 38% (n = 775) of these patients had hemophilia A (HA), 25% (n = 517) had von Willebrand disease (vWD), 7% (n = 132) had hemophilia B (HB), and 25% (n = 513) had less common factor deficiencies. The estimated age-standardized incidence rate (ASR) of HA and HB was 1.78-3.15/100,000 and 0.31-0.51/100,000, respectively. That of vWD was 1.38-1.95/100,000. The estimated ASR of HA showed increase over time though the number of new patients did not increase. Most patients with congenital bleeding disorders were younger than 19 years old (47.8%), and most were registered in Gyeonggi (22.1%) and Seoul (19.2%). CONCLUSION: This is the first nationwide population-based study of congenital bleeding disorders in Korea. This study provides data that will enable more accurate estimations of patients with vWD. This information will help advance the comprehensive care of congenital bleeding disorders. We need to continue to obtain more detailed information on patients to improve the management of these diseases.

Serum cytokine profiles in infants with infantile hemangiomas on oral propranolol treatment: VEGF and bFGF, potential biomarkers predicting clinical outcomes.

BACKGROUND: Oral propranolol has become first-line treatment for infantile hemangiomas (IHs). This study focused on identifying cytokines related to the biology of IH and early regression indicators of IH after propranolol treatment. METHODS: For inclusion, the patients had to be aged less than 1 year and have an IH with a largest diameter ≥2 cm. Patients were scheduled to receive 1 year of propranolol treatment. Serum cytokines involved in angiogenesis, vasculogenesis, and/or chronic inflammation were analyzed at 0, 1, and/or 12 months after treatment using Multiplex Luminex assays. RESULTS: Among the 49 evaluable patients, 33 completed the 1-year treatment: 16 showed excellent response and 12 had good response to propranolol. Significant decreases in serum MMP-2, bFGF, VEGF-α, and MCP-1 levels were observed after 1 year of treatment compared to pretreatment values. The maximal diameters of the lesions significantly correlated with pretreatment serum VEGF-α, bFGF, and MMP-9. Patients with higher bFGF and VEGF levels showed better response to propranolol at 1 year. CONCLUSION: MMP-2, VEGF-α, bFGF, and MCP-1 may involve in the biology of IH and their downregulation may be associated with involution processes of IH. Pretreatment bFGF and VEGF could be novel biomarkers for predicting response to propranolol. IMPACT: We found that decreases in the concentrations of MMP-2, bFGF, VEGF, and MCP-1 were associated with regression of the hemangioma, which indicates that one of the mechanisms of propranolol in the treatment of proliferative hemangiomas may involve downregulation of those cytokines. Patients with higher bFGF and VEGF levels showed better response to propranolol at 1 year. Importantly, serum bFGF higher than 37.07 pg/mL may predict an excellent response to propranolol. Therefore, along with the patient's age and the size and visual characteristics of the lesion, bFGF levels could help determine the viability of propranolol use in the treatment of IHs. Our study represented extensive serum profiling in IH, reporting the indicators and molecules clearly related to IH regression with propranolol treatment. The authors believe that monitoring serum cytokines, including MMP-2, bFGF, VEGF, and MCP-1, in IH patients could be important, in addition to clinical follow-up, for determining when to start and end propranolol treatment.

Prospective case control study of iron deficiency and the risk of febrile seizures in children in South Korea.

BACKGROUND: Febrile seizures are the most common type of seizure in the first 5 years of life, and many factors that increase seizure risk have been identified. This study was performed to examine the association between iron status and febrile seizures in children in South Korea. METHODS: A prospective unmatched case control study was performed in 63 cases of febrile seizures and 65 controls with febrile illness but no seizures. RESULTS: Serum iron, plasma ferritin, and transferrin saturation were significantly lower in children with febrile seizures compared to the controls. Iron deficiency, defined as ferritin < 30 ng/mL, was more prevalent in the febrile seizure group (49.2%) than in the control group (16.9%). Serum iron < 22 ng/dL (odds ratio 3.42, 95% confidence interval [CI] 1.31-8.9, P = 0.012) and ferritin < 30 ng/mL (odds ratio 6.18, 95% CI 2.32-16.42, P < 0.001) were associated with increased risk of developing febrile seizures in multivariate logistic regression analysis. CONCLUSION: These observations suggest that iron deficiency prior to development of anemia may increase risk of febrile seizures.

Langerhans Cell Histiocytosis of the Gastrointestinal Tract: Evidence for Risk Organ Status.

OBJECTIVE: To investigate the "risk status" of Langerhans cell histiocytosis (LCH) of the gastrointestinal tract. STUDY DESIGN: Outcomes from 43 published cases of patients with LCH and gastrointestinal tract involvement were matched to 43 patients with LCH without gastrointestinal tract involvement cared for at our institution. Comparisons were made of the 5-year overall survival rates determined from Kaplan-Meier survival curves for the entire cohort of patients, as well as subgroups defined by lack of risk organ involvement and later era of treatment (to control for temporal changes in LCH treatment regimens). In addition, an association between LCH-gastrointestinal tract and risk organ involvement was investigated. RESULTS: The 5-year overall survival for children with LCH-gastrointestinal tract (45.3%) was significantly worse than for those without gastrointestinal tract involvement (94.6%; P = .001). This difference remained significant after we excluded risk organ involvement (53.6%% vs 100%; P = .001), and analyzing subjects diagnosed after 2000 (75% vs 100%; P = .012). A 4-fold increase in risk organ involvement with LCH-gastrointestinal tract was observed (OR 4.359; 95% CI 1.75-10.82, P = .001). CONCLUSIONS: This limited retrospective study suggests that patients with LCH-gastrointestinal tract involvement may have decreased survival, independent of risk organ involvement, and provides evidence to support a prospective study to evaluate risk organ status of LCH-gastrointestinal tract. LCH-gastrointestinal tract may be associated with a 4-fold risk for risk organ involvement. Attention to gastrointestinal symptoms and LCH-gastrointestinal tract in young children diagnosed with LCH is warranted.

Molecular diagnosis of hereditary spherocytosis by multi-gene target sequencing in Korea: matching with osmotic fragility test and presence of spherocyte.

BACKGROUND: Current diagnostic tests for hereditary spherocytosis (HS) focus on the detection of hemolysis or indirectly assessing defects of membrane protein, whereas direct methods to detect protein defects are complicated and difficult to implement. In the present study, we investigated the patterns of genetic variation associated with HS among patients clinically diagnosed with HS. METHODS: Multi-gene targeted sequencing of 43 genes (17 RBC membrane protein-encoding genes, 20 RBC enzyme-encoding genes, and six additional genes for the differential diagnosis) was performed using the Illumina HiSeq platform. RESULTS: Among 59 patients with HS, 50 (84.7%) had one or more significant variants in a RBC membrane protein-encoding genes. A total of 54 significant variants including 46 novel mutations were detected in six RBC membrane protein-encoding genes, with the highest number of variants found in SPTB (n = 28), and followed by ANK1 (n = 19), SLC4A1 (n = 3), SPTA1 (n = 2), EPB41 (n = 1), and EPB42 (n = 1). Concurrent mutations of genes encoding RBC enzymes (ALDOB, GAPDH, and GSR) were detected in three patients. UGT1A1 mutations were present in 24 patients (40.7%). Positive rate of osmotic fragility test was 86.8% among patients harboring HS-related gene mutations. CONCLUSIONS: This constitutes the first large-scaled genetic study of Korean patients with HS. We demonstrated that multi-gene target sequencing is sensitive and feasible that can be used as a powerful tool for diagnosing HS. Considering the discrepancies of clinical and molecular diagnoses of HS, our findings suggest that molecular genetic analysis is required for accurate diagnosis of HS.

Risk Factor Analysis for Secondary Malignancy in Dexrazoxane-Treated Pediatric Cancer Patients.

PURPOSE: Dexrazoxane has been used as an effective cardioprotector against anthracycline cardiotoxicity. This study intended to analyze cardioprotective efficacy and secondary malignancy development, and elucidate risk factors for secondary malignancies in dexrazoxane-treated pediatric patients. MATERIALS AND METHODS: Data was collected from 15 hospitals in Korea. Patients who received any anthracyclines, and completed treatment without stem cell transplantation were included. For efficacy evaluation, the incidence of cardiac events and cardiac event-free survival rates were compared. Data about risk factors of secondary malignancies were collected. RESULTS: Data of total 1,453 cases were analyzed; dexrazoxane with every anthracyclines group (D group, 1,035 patients) and no dexrazoxane group (non-D group, 418 patients). Incidence of the reported cardiac events was not statistically different between two groups; however, the cardiac event-free survival rate of patients with more than 400 mg/m2 of anthracyclines was significantly higher in D group (91.2% vs. 80.1%, p=0.04). The 6-year cumulative incidence of secondary malignancy was not different between both groups after considering follow-up duration difference (non-D, 0.52%±0.37%; D, 0.60%±0.28%; p=0.55). The most influential risk factor for secondary malignancy was the duration of anthracycline administration according to multivariate analysis. CONCLUSION: Dexrazoxane had an efficacy in lowering cardiac event-free survival rates in patients with higher cumulative anthracyclines. As a result of multivariate analysis for assessing risk factors of secondary malignancy, the occurrence of secondary malignancy was not related to dexrazoxane administration.

Should healthy children who will undergo minor surgery be screened for coagulation disorder?

The objective of this study is to analyze the major causes of abnormal findings seen in the preoperative coagulation tests of asymptomatic pediatric patients and to discuss the usefulness of coagulation tests prior to minor surgery. Among patients who received minor surgery in Kyung Hee University Medical Center from March 2008 to April 2015, a total of 7114 pediatric patients (ages 1-18) were included in our study. Of these, 226 (3.1%) were referred to the pediatrics hematology-oncology department because of abnormal preoperative coagulation tests. A review of the coagulation tests indicate the majority (n = 216, 95.5%) have prolonged activated partial thromboplastin time (aPTT), whereas a smaller number (n = 10, 4.5%) have prolonged prothrombin time international normalized ratio (PT INR). When the coagulation tests were repeated, 136 displayed abnormal findings again. Of these 136 patients, 128 patients underwent mixing tests, and 127 showed results of correction and were composed as follows: normal (n = 83), subnormal (n = 26), factor deficiency (n = 15), and lupus anticoagulant positive (n = 3). Breakdown by factor deficiencies was as follows: (i) factor XII (n = 9), (ii) factor IX (n = 2), (iii) factors XII and IX (n = 1), (iv) factor VIII (n = 1), (v) factor XI (n = 1), (vi) von Willebrand factor (vWF; n = 1), and (vii) factor V (n = 1). Each factor activity range was mild (21%-39%), so no patients received preoperative medications or clotting factors/blood products. Even in the presence of factor deficiencies, bleeding symptoms were mild and postoperative complications did not occur. These results suggest that coagulation tests may not be needed in healthy children and should be reserved for patients with positive bleeding and/or family history.

Higher Gemcitabine Dose Was Associated With Better Outcome of Osteosarcoma Patients Receiving Gemcitabine-Docetaxel Chemotherapy.

BACKGROUND: Efficacy of gemcitabine and docetaxel (GEM + DOC) chemotherapy in patients with recurrent or refractory osteosarcoma was evaluated. METHODS: Data of 53 patients from 9 institutions, who received GEM (675 or 900 mg/m(2) on days 1 and 8) and DOC (100 mg/m(2) on day 8), were retrospectively reviewed. RESULTS: GEM + DOC was administered as adjuvant (n = 25) or palliative chemotherapy (n = 28). Patients received a median 3 courses (range, 1-10 courses). Objective response rate (CR + PR, where CR is complete response and PR is partial response) and disease control rate (CR+ PR + SD, where SD is stable disease) were 14.3% and 28.6%, respectively. Disease control rate was higher in patients receiving 900 mg/m(2) GEM than in patients receiving 675 mg/m(2) (50.0% vs. 12.5%, P = 0.03). Higher GEM dose was associated with better survival, both in adjuvant (1-year overall survival, 90.9 ± 8.7% vs. 38.5 ± 13.5%, P = 0.002) and palliative settings (50.0 ± 14.4% vs. 31.3 ± 11.6%, P = 0.04). CONCLUSIONS: Further studies are necessary to investigate the efficacy of more aggressive and higher doses of GEM + DOC chemotherapy in osteosarcoma.

Decreased Cystatin C-Estimated Glomerular Filtration Rate Is Correlated with Prolonged Hospital Stay in Transient Tachypnea of Newborn Infants.

BACKGROUND: Transient tachypnea of the newborn (TTN) is a benign disorder with a variable clinical course that often leads to hospitalization. The aim of this study was to assess and validate the relationship between the serum cystatin C level and symptom duration in infants with TTN. METHODS: Forty newborns presenting with TTN and who had undergone serum cystatin C (Cys C) tests on the first day of admission to the Kyung Hee University Hospital (Seoul, Korea) from 2009 to 2013 were included. The serum Cys C level, creatinine (Cr) level, estimated glomerular filtration rate (eGFR), and tachypnea duration were correlated retrospectively. RESULTS: The median gestation period was 37.8 ± 3.8 weeks and the mean birth weight was 3.2 ± 0.4 kg. Tachypnea duration was 3.3 ± 2.0 days. Serum Cys C and Cr levels were 1.7 ± 0.2 mg/L and 0.8 ± 1.2 mg/dL, respectively. Tachypnea duration was significantly positively correlated with the serum levels of Cys C and significantly negatively correlated with Cys C-based eGFR (p = 0.016), but was not significantly correlated with the serum Cr level or Cr-based eGFR. When tachypnea duration was compared between infants with Cys C level <1.6 mg/L (n = 15; Group A) and infants with Cys C level ≥ 1.6 mg/L (n = 25; Group B), the symptom duration was significantly shorter in Group A infants (p = 0.011). CONCLUSION: Tachypnea duration was shorter with higher Cys C-based eGFR in infants with TTN.

High Remission Rate of Chronic Immune Thrombocytopenia in Children: Result of 20-Year Follow-Up.

PURPOSE: This study examined the outcomes of children with chronic immune thrombocytopenia (ITP). MATERIALS AND METHODS: We retrospectively analyzed the medical records of all patients diagnosed with ITP from January 1992 to December 2011 at our institution. RESULTS: A total of 128 patients (64%) satisfied the criteria for newly diagnosed ITP, 31 (15%) for persistent ITP, and 41 (21%) for chronic ITP. The median age at diagnosis was 4.5 years (range, 1 month to 18 years). The median platelet count at diagnosis was 32×109/L. A comparison of the initial treatment data from 2001 to 2011 with those from 1992 to 2000 showed that the number of bone marrow examinations decreased, whereas observation increased. Chronic ITP presented at an older age than newly diagnosed and persistent ITP (6.6 years vs. 3.8 years vs. 4.1 years, respectively); however, the difference did not reach statistical significance (p=0.17). The probability of complete remission of chronic ITP was 50% and 76% at 2 and 5 years after diagnosis, respectively. Patients aged <1 year at diagnosis had a significantly better prognosis than did older patients (hazard ratio, 3.86; p=0.02). CONCLUSION: Children with chronic ITP showed a high remission rate after long-term follow-up. This study suggests that invasive treatments such as splenectomy in children with chronic ITP can be delayed for 4 to 5 years if thrombocytopenia and therapeutic medication do not affect the quality of life.

Clinical Impact of Epileptiform Discharge in Children With Attention-Deficit/Hyperactivity Disorder (ADHD).

The aim of this study was to investigate the prevalence and clinical significance of epileptiform discharges in patients with attention-deficit/hyperactivity disorder (ADHD). The authors retrospectively reviewed 180 children who were diagnosed with ADHD and had an electroencephalography (EEG) recording. Epileptiform discharges were found in 29 (16.1%) of 180 patients with ADHD. Of these, 15 (8.3%) had generalized epileptiform discharges and 14 (7.7%) had focal epileptiform discharges. The focal epileptiform discharges were most prevalent from the frontal (5/14) and rolandic area (5/14). Among the 29 patients with epileptiform discharges and ADHD, 5 patients had previous history of epilepsy and 4 patients developed epilepsy later, whereas none of the normal EEG group developed epilepsy. The authors suggest that interictal epileptiform discharges appear to be associated with seizure occurrence in children with ADHD and might reflect maturational pathophysiology overlapping with epilepsy.