Loss-of-function variants in TIAM1 are associated with developmental delay, intellectual disability, and seizures.

TIAM Rac1-associated GEF 1 (TIAM1) regulates RAC1 signaling pathways that affect the control of neuronal morphogenesis and neurite outgrowth by modulating the actin cytoskeletal network. To date, TIAM1 has not been associated with a Mendelian disorder. Here, we describe five individuals with bi-allelic TIAM1 missense variants who have developmental delay, intellectual disability, speech delay, and seizures. Bioinformatic analyses demonstrate that these variants are rare and likely pathogenic. We found that the Drosophila ortholog of TIAM1, still life (sif), is expressed in larval and adult central nervous system (CNS) and is mainly expressed in a subset of neurons, but not in glia. Loss of sif reduces the survival rate, and the surviving adults exhibit climbing defects, are prone to severe seizures, and have a short lifespan. The TIAM1 reference (Ref) cDNA partially rescues the sif loss-of-function (LoF) phenotypes. We also assessed the function associated with three TIAM1 variants carried by two of the probands and compared them to the TIAM1 Ref cDNA function in vivo. TIAM1 p.Arg23Cys has reduced rescue ability when compared to TIAM1 Ref, suggesting that it is a partial LoF variant. In ectopic expression studies, both wild-type sif and TIAM1 Ref are toxic, whereas the three variants (p.Leu862Phe, p.Arg23Cys, and p.Gly328Val) show reduced toxicity, suggesting that they are partial LoF variants. In summary, we provide evidence that sif is important for appropriate neural function and that TIAM1 variants observed in the probands are disruptive, thus implicating loss of TIAM1 in neurological phenotypes in humans.

An unexpected cause of chorea in an adolescent girl: systemic lupus erythematosus.

Involuntary movement disorders are rare in childhood. Hyperkinetic movement disorders including chorea stand as the leading cause. Although Sydenham chorea is the major diagnosis in most children and adolescents, appropriate differential diagnosis is fundamental for a final decision. A detailed and careful history as well as physical examination is the principal proceeding for accurate diagnosis. Herein, we report on an adolescent girl who was admitted to our hospital with chorea and subsequently diagnosed with systemic lupus erythematosus (SLE). Accompanying joint complaints in the patient's history, including growth retardation noticed during a physical examination and bicytopenia recognized in laboratory evaluation, increased the suspicion of SLE rather than Sydenham chorea in the patient. Central nervous system involvement defined as neuropsychiatric lupus presents wide clinical findings varying from stroke and seizures to psychosis and cognitive dysfunction. Although disease activity, persistently positive anticardiolipin antibodies, and lupus anticoagulant positivity are reported to be the most important risk factors in neuropsychiatric lupus, they are not always directly correlated. We present this patient in order to draw attention to the importance of physical examination and history in the differential diagnosis of chorea in childhood.

Homozygous missense VPS16 variant is associated with a novel disease, resembling mucopolysaccharidosis-plus syndrome in two siblings.

Disorders of intracellular trafficking are a group of inherited disorders, which often display multisystem phenotypes. Vacuolar protein sorting (VPS) subunit C, composed of VPS11, VPS18, VPS16, and VPS33A proteins, is involved in tethering of endosomes, lysosomes, and autophagosomes. Our group and others have previously described patients with a specific homozygous missense VPS33A variant, exhibiting a storage disease phenotype resembling mucopolysaccharidosis (MPS), termed "MPS-plus syndrome." Here, we report two siblings from a consanguineous Turkish-Arabic family, who have overlapping features of MPS and intracellular trafficking disorders, including short stature, coarse facies, developmental delay, peripheral neuropathy, splenomegaly, spondylar dysplasia, congenital neutropenia, and high-normal glycosaminoglycan excretion. Whole exome sequencing and familial segregation analyses led to the homozygous NM_022575.3:c.540G>T; p.Trp180Cys variant in VPS16 in both siblings. Multiple bioinformatic methods supported the pathogenicity of this variant. Different monoallelic null VPS16 variants and a homozygous missense VPS16 variant had been previously associated with dystonia. A biallelic intronic, probably splice-altering variant in VPS16, causing an MPS-plus syndrome-like disease has been very recently reported in two individuals. The siblings presented herein display no dystonia, but have features of a multisystem storage disorder, representing a novel MPS-plus syndrome-like disease, associated for the first time with VPS16 missense variants.

Parental Attitudes and Knowledge About Lumbar Puncture in Children.

OBJECTIVES: Lumbar puncture (LP) is fundamental for diagnosis and treatment; however, some parents do not provide consent for their children to undergo the procedure, which can make diagnosis and determination of the optimal treatment difficult. The present study aimed to describe the level of knowledge and attitudes toward LP of parents whose children were scheduled to undergo the procedure. METHODS: A prospective cross-sectional descriptive study of a convenience sample of parents of 84 children aged 2 months to 17 years scheduled for LP at a single academic children's hospital between 2015 and 2017. Parents were administered a written survey and interviewed by a physician other than the person who did the LP. Data on parental level of knowledge and attitudes regarding LP, in addition to reasons for refusal, were collected.The parents of 84 patients scheduled for LP due to various indications were administered a face-to-face survey interview. The survey was used to collect parental demographic data, as well as opinions and knowledge about LP and postinterventional complications. RESULTS: The mean age of the 84 patients (57% male and 43% female) was 6.4 ± 5.17 years. Lumbar puncture was planned for the presumptive diagnosis of neurological disease in 45.25% of the patients, central nervous system infection in 45.25%, and acute encephalopathy in 9.5%. Among the parents, 65% (n = 55) had no knowledge or attitude about LP prior to the survey interview. The most common parental concern related to LP was paralysis (25%), followed by infertility (2%), mental retardation (1%), and disease progression (1%). Only 4.7% of the parents did not provide consent for their child to undergo LP. CONCLUSIONS: We found that most parents had little knowledge about LP, and the most common parental concern was paralysis. Despite this, in our study, only 5% of parents did not consent to LP.

Secondary hemophagocytic lymphohistiocytosis in pediatric patients: a single center experience and factors that influenced patient prognosis.

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening syndrome of excessive immune activation. Secondary HLH syndrome develops as a complication of infection, drugs, rheumatologic conditions, or malignancy. The main objectives of this work were to identify the etiology of secondary HLH and prognostic factors associated with mortality. Patients diagnosed with secondary HLH, between January 2011 and December 2016, were retrospectively included in this study. We analyzed clinical and laboratory findings as well as prognostic factors from 24 pediatric patients diagnosed with secondary HLH. The mean age of patients at the time of diagnosis was 79.9 ± 68.7 months (range: 2-202) and 54.2% of the patients were male. The most frequent HLH-2004 criterion was fever (100%). Underlying triggers of HLH were as follows: 13 (54.1%) infections, juvenile idiopathic arthritis in 5 patients (20.8%), drugs in 3 patients (12.5%), malignancies in 2 (0.8%), Kawasaki disease in 1 (0.4%) patient, and 1 (0.4%) with unknown triggers. The median time of diagnosis was 3 days (1-67 days). Overall, the mortality rate was 20.8%. In our logistic regression model, factors associated with mortality were decreased albumin levels (OR1 = 2.3[1.48-3.43]) and etoposide usage (OR2 = 1.22 [1.14-1.89]). The patient's 30-day survival was inferior among patients whose albumin level was 2 g/dL or less compared to those over 2 g/dL. Increased awareness of the underlying condition is critical in HLH patients. Our study emphasizes the prognostic significance of albumin level.

Time-averaged hemoglobin values, not hemoglobin cycling, have an impact on outcomes in pediatric dialysis patients.

BACKGROUND: During erythropoietin-stimulating agent (ESA) treatment, hemoglobin (Hb) levels usually fluctuate; this phenomenon is known as "Hb cycling (HC)." In this study, we aimed to evaluate the predictors of HC and its impact on left ventricular hypertrophy (LVH) as a patient-important outcome parameter in pediatric dialysis patients. METHODS: Records of patients followed up in nine pediatric nephrology centers between 2008 and 2013 were reviewed. More than 1 g/dL decrease or increase in Hb level was considered as HC. Patients were divided into two groups according to 12-month Hb trajectory as rare cycling (RC) (≤ 3) and frequent cycling (FC) (> 3 fluctuation) as well as three groups based on T-A-Hb levels: < 10, 10-11, and > 11 g/dL. RESULTS: Two hundred forty-five dialysis (160 peritoneal dialysis (PD) and 85 hemodialysis (HD)) patients aged 12.3 ± 5.1 (range 0.5-21) years were enrolled in this study. Fifty-two percent of the patients had RC, 45% had FC, and only 3% had no cycling. There were no differences between HC groups with respect to age, dialysis modality, having anemia, hospitalization rate, residual urine volume, and mortality. Although left ventricular mass index (LVMI) tended to be higher in RC than FC group (65 ± 37 vs 52 ± 23 g/m2.7, p = 0.056), prevalence of LVH was not different between the groups (p = 0.920). In regression analysis, FC was not a risk factor for LVH, but low T-A Hb level (< 10 g/dL) was a significant risk for LVH (OR = 0.414, 95% CI 0.177-0.966, p = 0.04). The target Hb levels were more often achieved in PD patients, and the number of deaths was significantly lower in non-anemic patients (Hb level > 11 g/dL). CONCLUSION: Hb cycling is common among dialysis patients. Severity of anemia rather than its cycling has more significant impact on the prevalence of LVH and on inflammatory state.

Recurrent hepatic failure and status epilepticus: an uncommon presentation of hyperargininemia.

Argininemia is a rare hereditary disease due to a deficiency of hepatic arginase, which is the last enzyme of the urea cycle and hydrolyzes arginine to ornithine and urea. Herein we report a patient with arginase I (ARG1) deficiency who presented with recurrent nonconvulsive status epilepticus and liver failure. A novel homozygous frameshift mutation c.703_707delGGACTinsAGACTGGACC (p.G235Rfs*20) was detected.

Ranitidine-induced black tongue: A case report.

Black tongue is a rare, benign, self-limiting disorder caused by certain conditions and some medications. We report the first case of a child diagnosed with black tongue associated with ranitidine use. We report our case to emphasize the rare side effect of this frequently used drug. Health care professionals should be aware of the likelihood of ranitidine-induced black tongue in clinical practice.

Results of native and transplant kidney biopsies of children in a single center over a 15 years period.

Renal biopsy is an important diagnostic procedure in pediatric nephrology. This study retrospectively investigates the indications, results and complications in a single tertiary children's hospital in Turkey. We evaluated the native and transplant kidney biopsies in Gazi University Pediatric Nephrology Department between 2001 and 2015. A total of 196 biopsies (144 natives and 52 transplants) were included into the study. The mean age of the patients was respectively 10.8 ± 3.5, 13.9 ± 1.5 years. The main indication for a biopsy was non-nephrotic proteinuria with or without hematuria (n= 35), followed by steroid-resistance nephrotic syndrome (SRNS) (n = 34) and Henoch-Schönlein purpura (HSP)-related proteinuria (n = 20) for native kidneys. We found that focal segmental glomerulosclerosis (FSGS) (11.7%) was the most common histopathologic diagnosis for native kidneys, but acute cellular rejection (7.6%) was the most common histopathologic diagnosis for transplant kidneys. The complication rate in our study was founded 6.6% totally. Different complication rates were found in other studies; however, we think that this difference comes from the inspecting methodology of the complications. Hence, we wanted to share our own experience in the context of other studies in the literature.

Effects of whole blood viscosity and plasma NOx on cardiac function and cerebral blood flow in children with chronic kidney disease

Background/aim: The aim of the study was to investigate the effects of whole blood viscosity and plasma nitric oxide on cerebral and cardiovascular risks associated with chronic kidney disease. Materials and methods: The study group consisted of 40 pediatric patients and 21 healthy control subjects. Hematologic and biochemical variables, viscosity and plasma nitric oxide levels, echocardiographic findings, and middle cerebral artery blood flow velocity were examined. Results: Viscosity values of patients were significantly lower than those of the control group. Lower values of hematocrit, total protein, and albumin and higher values of ferritin in all patient groups resulted in significantly low viscosity levels. Plasma nitric oxide levels were higher in all patient groups than those in the controls. No statistically significant difference was present in middle cerebral artery blood flow velocity between the patient and control groups. Even when systolic functions were normal, the patient group had significant deterioration in diastolic functions, suggesting morbidity and mortality risks. Conclusions: Cerebral blood flow velocities were not affected by viscosity and nitric oxide levels, suggesting that cerebral circulation has the ability to make adaptive modulation. The metabolism of nitric oxide levels needs further investigation and studies in patients with chronic renal disease.

Effect of plasma NOx values on cardiac function in obese hypertensive and normotensive pediatric patients.

BACKGROUND: Hypertension (HT) is a major comorbidity of obesity that is associated with an increased risk of cardiovascular disease and higher mortality. The aim of our study was to evaluate cardiac function in obese hypertensive (OHT) and obese normotensive (ONT) pediatric patients and determine the effects of plasma nitric oxide (NOx) values on cardiac function, while demonstrating the role of plasma NOx in HT in obese pediatric patients. METHODS: The study population consisted of 62 patients (27 boys, 35 girls), aged 13-18 years and 21 age-matched healthy controls. All subjects enrolled in the study underwent echocardiography (Echo) evaluation and ambulatory blood pressure monitoring for HT. Plasma NOx and biochemical values were studied in both patient groups separately. RESULTS: Plasma NOx levels were found to be lower in the OHT group than in the ONT and control groups (p < 0.001) and to be negatively correlated with left ventricular mass index values (p < 0.05). Both the OHT and ONT groups had concentric hypertrophy of the heart. CONCLUSIONS: Plasma NOx plays an essential role in obesity-induced HT. Concentric hypertrophy of the left ventricle was found in both the OHT and ONT groups, indicating structural deformation of the heart.

The evaluation of bone metabolism in children with renal transplantation.

This study aims to evaluate BMD and bone biomarkers and to investigate the effects of immunosuppressives on bone disease after RTx. Thirty-three RTR aged 16.7 ± 3.7 yr and healthy controls (n = 32) were enrolled. There was no difference between pre-RTx BMD and BMD at the time of study (45.9 ± 30.9 months after RTx), while both values were lower than controls (p < 0.01 and p < 0.05, respectively). Worst BMD scores were obtained at sixth month after RTx (-0.2 ± 0.9) and best at fourth year (1.4 ± 1.3). 25-hydroxy-(OH) vitamin D and OPG were higher in RTR (p < 0.001). BMD z scores negatively correlated with OPG and cumulative CS doses at the time of study (r = -0.344, p < 0.05 and r = -0.371, p < 0.05, respectively). Regression analysis revealed OPG as the only predictor of BMD (ß -0.78, 95% CI -0.004 to -0.013, p < 0.001). The increase in OPG, a significant predictor of BMD, could either be secondary to graft dysfunction or for protection against bone loss. CS doses should be minimized to avoid their untoward effects on bone metabolism.

Hemolytic Anemia due to Glucose 6 Phosphate Dehydrogenase Deficiency Triggered by Type 1 Diabetes Mellitus

Glucose 6 phosphate dehydrogenase (G6PD) is expressed in all tissues and is necessary to maintain oxidant stress capacity of cells. G6PD deficiency is the most common enzymopathy in humans and is among the important causes of hemolytic anemia. It has been reported that severe hemolytic anemia due to G6PD deficiency may develop in newly diagnosed diabetes, especially during the correction of hyperglycemia. To date, nine cases have been published. Genetic analysis was not performed for G6PD deficiency in these published patients. We present a case of hemolytic anemia due to G6PD deficiency secondary to newly diagnosed type 1 diabetes mellitus. Genetic testing was performed for the index patient and revealed a previously reported missense pathogenic variant (c.653C>T; p.Ser218Phe) in the G6PD gene.