Inherited platelet function disorders (IPFDs) are rare and underdiagnosed in individuals with clinically significant bleeding diathesis. IPFDs are classified according to the causative molecular defects involved in the process of primary hemostasis of platelets, which include the following: 1) adhesion (e.g., Bernard–Soulier syndrome and pseudo-von Willebrand disease), 2) activation (e.g., adenosine diphosphatase receptor defect and thromboxane A2 receptor defect), 3) signal transduction and granule secretion (e.g., gray platelet syndrome, Paris–Trousseau/Jacobsen syndrome, Chediak– Higashi syndrome, and Hermansky–Pudlak syndrome), 4) aggregation (e.g., Glanzmann thrombasthenia), and 5) procoagulant activity (e.g., Scott syndrome). Patients with IPFDs typically present with unexpected mucocutaneous bleeding during early childhood. The diagnosis of these conditions requires several laboratory tests including complete blood cell count, peripheral blood smear, platelet function analysis, light-transmission aggregometry, flow cytometry, electron microscopy, and genetic analysis. Platelet transfusion has been the mainstay of treatment. However, antifibrinolytics, desmopressin, and recombinant activated factor VII are also effective when used as a monotherapy or adjunctive therapy. Importantly, the prevention of bleeding event is the most basic strategy in the management of IPFDs. This review aimed to assess the normal platelet physiology and summarize the current knowledge about the molecular defects, diagnostic evaluation, and treatment strategies of the respective IPFDs. If the cause of the bleeding tendency is difficult to identify, IPFDs should be considered.

Jacobsen syndrome (JS) is a contiguous gene syndrome resulting from a deletion of chromosome 11q, with various clinical manifestations. A post-term small for gestational age infant was born by normal vaginal delivery without trauma or vacuum extraction. On day 5, right parietotemporal scalp swelling developed, with petechiae on the right cheek and thrombocytopenia (platelets: 63,000/µL). A prominent forehead, wide-set eyes, short and upturned nose were noted. Karyotyping and microarray analysis demonstrated del(11)(q24q25), consistent with Jacobsen syndrome. Brain magnetic resonance imaging (MRI) revealed a huge cephalhematoma. The patient is scheduled to receive periodic evaluations for thrombocytopenia and heart, kidney, abdominal malformations, ophthalmologic and auditory problems. There are lots of newborns with cephalhematoma or petechiae after birth. Not all newborns with these symptoms need evaluations, but if they have these symptoms with suspect features or appearances, we need to go through further evaluations.
Brain ; Cheek ; Forehead ; Gestational Age ; Heart ; Humans ; Infant ; Infant, Newborn ; Jacobsen Distal 11q Deletion Syndrome* ; Karyotyping ; Kidney ; Magnetic Resonance Imaging ; Microarray Analysis ; Nose ; Parturition* ; Purpura ; Scalp ; Thrombocytopenia* ; Vacuum

PURPOSE: An adequate vitamin D level is important for normal growth, cancer prevention, controlling hormones, and immune regulation. However, no study has investigated vitamin D status in patients with serious illnesses, such as malignancies, malabsorption diseases, or prematurity in Korean children. Thus, we analyzed the results of 25-hydroxyvitamin D3 (25-D) levels in children in a single tertiary medical center. METHODS: Children who had their vitamin D level evaluated at Keimyung University Dongsan Medical Center from January 2004 to December 2014 were included. We reviewed the medical records and laboratory test results. RESULTS: Ninety-three children (male:female = 48:45) who had their vitamin D levels measured were included. The most common reason for measuring vitamin D level was hypocalcemia with or without neurological signs. Among the subjects, 61 children had hypovitaminosis D (25-D < 30 ng/mL). A positive correlation was detected between 25-D and total calcium levels (p = 0.001). Negative correlations were found between 25-D and immunoreactive parathyroid hormone (iPTH) levels (p = 0.002) and between 25-D and alkaline phosphatase (ALP) levels (p = 0.021). Twenty-three subjects (37.7%) had a critical underlying condition, including a hemato-oncologic issue (18.0%), gastrointestinal or nutritional problem (11.5%), and prematurity or low birth weight (8.2%). CONCLUSION: The levels of total calcium, ALP, and iPTH were correlated with 25-D level. An underlying malignancy, malabsorption issues, or prematurity may be risk factors for hypovitaminosis D in children.
Alkaline Phosphatase ; Calcifediol ; Calcium ; Child* ; Humans ; Hypocalcemia ; Infant, Low Birth Weight ; Infant, Newborn ; Medical Records ; Parathyroid Hormone ; Risk Factors* ; Vitamin D

PURPOSE: The aim of this study was to evaluate the diagnostic accuracy of urinary biomarkers, such as neutrophil gelatinase-associated lipocalin (uNGAL) and β-2 microglobulin (uB2MG), in early detection of urinary tract infection (UTI) in infants aged < 3 months with fever. METHODS: A total of 422 infants aged < 3 months (male:female=267:155; mean age, 56.4 days), who were admitted for fever, were retrospectively included in this study. We compared uNGAL and uB2MG between the UTI and non-UTI groups at the time of admission. The sensitivity, specificity, accuracy, and area under the curve (AUC) of uNGAL and uB2MG for use in diagnosing UTI were assessed. RESULTS: Among 422 patients, 102 (24.2%) were diagnosed with UTI. Levels of uNGAL were higher in the UTI group than in the non-UTI group (366.6 ng/mL vs. 26.9 ng/mL, P < 0.001). Levels of uB2MG were not different between the 2 groups. Multivariate analysis revealed that uNGAL was an independent predictive factor for UTI (P=0.033). The sensitivity, specificity, and accuracy were 90.2%, 92.5%, and 91.9% for uNGAL, and 48.0%, 43.8%, and 44.8% for uB2MG, respectively. AUC of uNGAL was 0.942 and that of uB2MG was 0.407. CONCLUSION: Accuracy of uNGAL in the diagnosis of UTI is high in febrile infants aged < 3 months. uNGAL can help in the early diagnosis and treatment of UTI in infants.
Area Under Curve ; Biomarkers ; Diagnosis ; Early Diagnosis ; Fever ; Humans ; Infant ; Lipocalins ; Multivariate Analysis ; Neutrophils ; Retrospective Studies ; Sensitivity and Specificity ; Urinary Tract Infections ; Urinary Tract

BACKGROUND: Reactive thrombocytosis (RT) is a common condition among children, although no studies have examined the etiology or clinical characteristics of RT among Korean children. METHODS: This retrospective study evaluated children with RT at a single Korean tertiary center during a 10-year period. RESULTS: RT accounted for 13.5% of children who were admitted to the pediatric ward (4,113/30,355): mild RT, 82.7%; moderate RT, 14.1%; severe RT, 1.1%; and extreme RT, 2.1%. There was a negative correlation between platelet count and Hb level (P=0.008). There were positive correlations between platelet count and WBC (P=0.001), erythrocyte sedimentation rate (ESR) (P=0.007), and admission duration (P=0.006). The most common cause of RT was infection and the second most common was Kawasaki disease (KD). The highest proportion of lower respiratory tract infection was observed in extreme RT (P < 0.001). The proportion of KD was highest in extreme RT (P < 0.001) and in children aged 1–7.9 years (P < 0.001). The proportion of refractory KD was highest in extreme RT (P=0.005). In cases of KD, there was a positive correlation between platelet count and fever duration (P=0.006). Non-KD autoimmune inflammation was only observed in mild/moderate RT, and its proportion was highest in children aged 8–18 years (P < 0.001). CONCLUSION: In children, more severe RT was associated with lower Hb, increased WBC, ESR, and prolonged admission. With respiratory infection or KD, extreme RT was associated with more severe disease course.
Blood Sedimentation ; Child* ; Fever ; Humans ; Inflammation ; Mucocutaneous Lymph Node Syndrome ; Platelet Count ; Respiratory Tract Infections ; Retrospective Studies* ; Thrombocytosis*

BACKGROUND: Pilocytic astrocytoma (PA) is a brain tumor that is relatively more common in children and young adults. METHODS: We retrospectively reviewed the medical records of patients with PA treated at a single center between 1988 and 2018. RESULTS: We included 31 subjects with PA. The median age at diagnosis was 13.4 years, and the median follow-up duration was 9.9 years. The total PA group had a 10-year disease-specific survival (DSS) rate of 92.6% [95% confidence interval (CI), 82.6–100] and 10-year progression-free survival (PFS) rate of 52.8% (95% CI, 32.0–73.6). In patients aged <20 years, tumors were more likely to be located in sites in which gross total tumor resection (GTR) was impossible. No statistically significant difference in 10-year DSS was found between the GTR (100%) and non-GTR (89.7%; 95% CI, 76.2–100; p=0.374) groups. However, a statistically significant difference in 10-year PFS was found between the GTR (100%) and non-GTR groups (30.7%; 95% CI, 8.6–52.8; p=0.012). In the non-GTR group, no statistically significant difference in 10-year DSS was found between the patients who received immediate additional chemotherapy and/or radiotherapy (Add-Tx group, 92.9%; 95% CI, 79.4–100) and the non-Add-Tx group (83.3%; 95% CI, 53.5–100; p=0.577). No statistically significant difference in 10-year PFS was found between the Add-Tx group (28.9%; 95% CI, 1.7–56.1) and non-Add-Tx group (33.3%; 95% CI, 0–70.9; p=0.706). CONCLUSION: The PFS of the patients with PA in our study depended only on the degree of surgical excision associated with tumor location. This study is limited by its small number of patients and retrospective nature. A multicenter and prospective study is necessary to confirm these findings.
Adolescent ; Astrocytoma ; Brain Neoplasms ; Child ; Diagnosis ; Disease-Free Survival ; Drug Therapy ; Follow-Up Studies ; Glioma ; Humans ; Medical Records ; Prognosis ; Prospective Studies ; Radiotherapy ; Retrospective Studies ; Survivors ; Young Adult

A 9-year-old Tajikistani girl presented to Keimyung University Dongsan Medical Center for evaluation of a skin lesion on her left eyelid, focal alopecia, unilateral ventricular dilatation, and aortic coarctation. She was diagnosed with encephalocraniocutaneous lipomatosis (ECCL) according to Moog's diagnostic criteria. Café-au-lait spots were found on the left side of her trunk. Multiple nonossifying fibromas were found on her left proximal humerus, left distal femur, both proximal tibias, and left proximal fibula, suggesting Jaffe-Campanacci syndrome (JCS), following imaging of the extremities. Many JCS cases with multiple Café-au-lait macules, multiple nonossifying fibromas may actually have Neurofibromatosis type-1 (NF1). Thus, comprehensive molecular analysis to exclude NF1 mutation was performed using her blood sample. The NF1 mutation was not found. Her height was under the 3rd percentile and her bone age was delayed as compared with her chronological age. Baseline growth hormone (GH) level was below the normal range. Using the insulin stimulation and levo-dihydroxyphenylalanine tests, GH deficiency was confirmed. We present a case of GH deficiency with typical features of ECCL and JCS.

A 9-year-old Tajikistani girl presented to Keimyung University Dongsan Medical Center for evaluation of a skin lesion on her left eyelid, focal alopecia, unilateral ventricular dilatation, and aortic coarctation. She was diagnosed with encephalocraniocutaneous lipomatosis (ECCL) according to Moog's diagnostic criteria. Café-au-lait spots were found on the left side of her trunk. Multiple nonossifying fibromas were found on her left proximal humerus, left distal femur, both proximal tibias, and left proximal fibula, suggesting Jaffe-Campanacci syndrome (JCS), following imaging of the extremities. Many JCS cases with multiple Café-au-lait macules, multiple nonossifying fibromas may actually have Neurofibromatosis type-1 (NF1). Thus, comprehensive molecular analysis to exclude NF1 mutation was performed using her blood sample. The NF1 mutation was not found. Her height was under the 3rd percentile and her bone age was delayed as compared with her chronological age. Baseline growth hormone (GH) level was below the normal range. Using the insulin stimulation and levo-dihydroxyphenylalanine tests, GH deficiency was confirmed. We present a case of GH deficiency with typical features of ECCL and JCS.