Age-specific causes of upper gastrointestinal bleeding in children

The etiology of upper gastrointestinal bleeding (UGIB) varies by age, from newborns to adolescents, with some of the causes overlapping between age groups. While particular causes such as vitamin K deficiency and cow's milk protein allergy are limited to specific age groups, occurring only in neonates and infants, others such as erosive esophagitis and gastritis may be identified at all ages. Furthermore, the incidence of UGIB is variable throughout the world and in different hospital settings. In North America and Europe, most UGIBs are non-variceal, associated with erosive esophagitis, gastritis, and gastric and duodenal ulcers. In recent years, the most common causes in some Middle Eastern and Far Eastern countries are becoming similar to those in Western countries. However, variceal bleeding still predominates in certain parts of the world, especially in South Asia. The most severe hemorrhage arises from variceal bleeding, peptic ulceration, and disseminated intravascular coagulation. Hematemesis is a credible indicator of a UGI source of bleeding in the majority of patients. Being familiar with the most likely UGIB causes in specific ages and geographic areas is especially important for adequate orientation in clinical settings, the use of proper diagnostic tests, and rapid initiation of the therapy. The fundamental approach to the management of UGIB includes an immediate assessment of severity, detecting possible causes, and providing hemodynamic stability, followed by early endoscopy. Unusual UGIB causes must always be considered when establishing a diagnosis in the pediatric population because some of them are unique to children. Endoscopic techniques are of significant diagnostic value, and combined with medicaments, may be used for the management of acute bleeding. Finally, surgical treatment is reserved for the most severe bleeding.

Sensorineural Hearing Loss in a Child with Succinic Semialdehyde Dehydrogenase Deficiency

Succinic semialdehyde dehydrogenase (SSADH) deficiency is a rare autosomal-recessive disorder of gamma-aminobutyric acid (GABA) metabolism, resulting in accumulation of GABA and gamma-hydroxybutyric acid (GHB) in physiological fluids. Approximately 450 patients have been diagnosed worldwide with this inherited neurotransmitter disorder. We report on a five-year-old male patient, homozygous for the pathogenic variant (NM_170740:c.1265G>A) in ALDH5A1 presenting with an unexpected association of typical SSADH deficiency manifestations with bilateral sensorineural hearing loss (SNHL). Brainstem evoked response audiometry (BERA) testing showed mid-frequency sensorineural hearing damage that suggested a hereditary component to SNHL. Whole exome sequencing (WES) failed to discern other genetic causes of deafness. Several variants of uncertain significance (VUS) detected in genes known for their role in hearing physiology could not be verified as the cause for the SNHL. It is known that central auditory processing depends on a delicate balance between excitatory and inhibitory neurotransmission, and GABA is known to play a significant role in this process. Additionally, excessive concentrations of accumulated GABA and GBH are known to cause a down-regulation of GABA receptors, which could have an adverse influence on hearing function. However, these mechanisms are very speculative in context of SNHL in a patient with inherited disorder of GABA metabolism. Injury of the globi pallidi, one of hallmarks of SSADH deficiency, could also be a contributory factor to SNHL, as was suspected in some other inborn errors in metabolism. We hope that this case will contribute to the understanding of phenotypic complexity of SSADH deficiency.

Ambiguous Genitalia and Lissencephaly in A 46,XY Neonate with a Novel Variant of Aristaless Gene

INTRODUCTION

Disorders of sexual development can present isolated or as a part of complex genetic syndromes.

CASE PRESENTATION

A newborn with ambiguous genitalia and prenatally diagnosed brain malformations was referred to our hospital. Prenatal ultrasound examination and MRI showed lissencephaly and absence of the corpus callosum. At admission, physical examination revealed microphallus, hypospadia and complete fusion of labioscrotal folds with nonpalpable gonads, normal blood pressure and serum biochemistry. Cortisol level was normal (201 nmol/L), testosterone elevated (14.4 nmol/L), FSH 0.1 IU/L, LH 0.7 IU/L, estradiol 241 pmol/L. Seizures were noted on the 2^nd day and the child was started on anticonvulsives. When 17-OHP level results came back elevated (200 nmol/L), ACTH test was performed and the child was started on hydrocortisone and fludrocortisone treatment. Congenital adrenal hyperplasia became unlikely when karyotype result showed normal male karyotype (46, XY, SRY+) with no Mullerian structures seen on ultrasonographic exam. As association of ambiguous genitalia and lissencephaly strongly suggested a mutual genetic background, diagnosis of X-linked lissencephaly with ambiguous genitalia (X-LAG) became apparent.

CONCLUSIONS

The presented case highlights the importance of looking at the whole clinical picture instead of separate isolated findings with emphasis on patient-centered approach guided by clinical findings and patient history.

Impact of genotype on neutropenia in a large cohort of Serbian patients with glycogen storage disease type Ib

BACKGROUND

Glycogen storage disease type Ib (GSD-Ib) is an inherited metabolic disorder caused by autosomal recessive mutations in SLC37A4 coding for the glucose-6-phosphate transporter. Neutropenia represents major feature of GSD-Ib along with metabolic disturbances. Previous research in GSD-Ib patients did not reveal significant genotype-phenotype correlation. Our objective was to explore the frequency and severity of neutropenia and it's complications in relation to genotype of GSD-Ib patients.

METHODS

We estimated cumulative incidence of neutropenia and severe neutropenia, relation of genotype to absolute neutrophil count (ANC), and dynamics of ANC during serious bacterial infections (SBI) in a cohort of Serbian GSD Ib patients. Impact of genotype on GSD Ib-related inflammatory bowel disease (IBD) was also assessed.

RESULTS

Absolute neutrophil count (ANC) < 1500/mm³ was present in all 33 patients, with severe neutropenia (ANC<500/mm³) occurring in 60.6% of patients. The median age at neutropenia onset was 24 months, while severe neutropenia developed at median of 4.5 years. The ANC was elevated during 90.5% episodes of SBI. Genotypes c.81T>A/c.785G>A and c.81T>A/c.1042_1043delCT are associated with earlier onset of neutropenia. Patients carrying c.785G>A mutation express a higher capacity for ANC increase during SBI. Inflammatory bowel disease was diagnosed in 8 patients (24.2% of total) with median age of onset at 7 years. Risk for IBD occurrence was not significantly affected by gender, genotype and severity of neutropenia.

CONCLUSIONS

We may conclude that certain mutations in SLC37A4 influence the risk for severe neutropenia occurrence but also affect the capacity to increase ANC during SBI.

Genetic characterization of GSD I in Serbian population revealed unexpectedly high incidence of GSD Ib and 3 novel SLC37A4 variants

Glycogen storage disease (GSD) type I is inborn metabolic disease characterized by accumulation of glycogen in multiple organs. We analyzed 38 patients with clinical suspicion of GSD I using Sanger and next-generation sequencing (NGS). We identified 28 GSD Ib and 5 GSD Ia patients. In 5 patients, GSD III, VI, IX, cholesteryl-ester storage disease and Shwachman-Diamond syndrome diagnoses were set using NGS. Incidences for GSD Ia and GSD Ib were estimated at 1:172 746 and 1:60 461 live-births, respectively. Two variants were identified in G6PC gene: c.247C>T (p.Arg83Cys) and c.518T>C (p.Leu173Pro). In SLC37A4 gene, 6 variants were detected. Three previously reported variants c.81T>A (p.Asn27Lys), c.162C>A (p.Ser54Arg) and c.1042_1043delCT (p.Leu348Valfs*53) accounted for 87% of all analyzed alleles. Computational, transcription studies and/or clinical presentation in patients confirmed pathogenic effect of 3 novel variants: c.248G>A (p.Gly83Glu), c.404G>A (p.Gly135Asp) and c.785G>A (p.Ser263Glyfs*33 or p.Gly262Asp). In the cohort, hepatomegaly, hypoglycemia and failure to thrive were the most frequent presenting signs of GSD Ia, while hepatomegaly and recurrent bacterial infections were clinical hallmarks of GSD Ib. All GSD Ib patients developed neutropenia while 20.6% developed inflammatory bowel disease. Our study revealed the highest worldwide incidence of GSD Ib. Furthermore, description of 3 novel variants will facilitate medical genetic practice.

Novel intragenic deletions within the UBE3A gene in two unrelated patients with Angelman syndrome: case report and review of the literature

BACKGROUND

Patients with Angelman syndrome (AS) are affected by severe intellectual disability with absence of speech, distinctive dysmorphic craniofacial features, ataxia and a characteristic behavioral phenotype. AS is caused by the lack of expression in neurons of the UBE3A gene, which is located in the 15q11.2-q13 imprinted region. Functional loss of UBE3A is due to 15q11.2-q13 deletion, mutations in the UBE3A gene, paternal uniparental disomy and genomic imprinting defects.

CASE PRESENTATION

We report here two patients with clinical features of AS referred to our hospital for clinical follow-up and genetic diagnosis. Methylation Specific-Multiplex Ligation-Dependent Probe Amplification (MS-MLPA) of the 15q11.2-q13 region was carried out in our laboratory as the first diagnostic tool detecting two novel UBE3A intragenic deletions. Subsequently, the MLPA P336-A2 kit was used to confirm and determine the size of the UBE3A deletion in the two patients. A review of the clinical features of previously reported patients with whole UBE3A gene or partial intragenic deletions is presented here together with these two new patients.

CONCLUSION

Although rare, UBE3A intragenic deletions may represent a small fraction of AS patients without a genetic diagnosis. Testing for UBE3A intragenic exonic deletions should be performed in those AS patients with a normal methylation pattern and no mutations in the UBE3A gene.

Postprandial hyperinsulinemic hypoglycemia in a child as a late complication of esophageal reconstruction

BACKGROUND

Postprandial hyperinsulinemic hypoglycemia (PHH) is an increasingly recognized complication of gastric bypass surgery in obese adults, distinct from the "dumping syndrome".

CASE PRESENTATION

Upon birth, primary repair of esophageal atresia was performed, and at the age of 14 months definite esophageal reconstruction was performed. At the age of 3 years, recurrent brief episodes of symptomatic hypoglycemia started. At the age of 5.7 years the girl was admitted to our clinic and investigations indicated hyperinsulinemic hypoglycemia. Oral glucose tolerance test (OGTT) and continuous glucose monitoring results revealed frequent postprandial hypoglycemic events, which were always preceded by early postprandial hyperglycemia. It was concluded that the patient had PHH caused by a delayed and hyperinsulinemic response to carbohydrate intake as a result of esophagogastric surgery. Treatment with acarbose was titrated using flash glucose monitoring, which resulted in satisfactory glucose regulation.

CONCLUSIONS

This is the first described case of a child with PHH following esophageal reconstruction.

Genotype-phenotype correlation in 44 Czech, Slovak, Croatian and Serbian patients with mucopolysaccharidosis type II

Mucopolysaccharidosis type II (Hunter syndrome, MPS II, OMIM 309900) is an X-linked lysosomal storage disorder caused by deficiency of iduronate-2-sulfatase (IDS). We analyzed clinical and laboratory data from 44 Slavic patients with this disease. In total, 21 Czech, 7 Slovak, 9 Croatian and 7 Serbian patients (43 M/1 F) were included in the study (median age 11.0 years, range 1.2-43 years). Birth prevalence ranged from 1:69,223 (Serbia) to 1:192,626 (Czech Rep.). In the majority of patients (71%), the disease manifested in infancy. Cognitive functions were normal in 10 patients. Four, six and 24 patients had mild, moderate, and severe developmental delay, respectively, typically subsequent to developmental regression (59%). Residual enzyme activity showed no predictive value, and estimation of glycosaminoglycans (GAGs) had only limited importance for prognosis. Mutation analysis performed in 36 families led to the identification of 12 novel mutations, eight of which were small deletions/insertions. Large deletions/rearrangements and all but one small deletion/insertion led to a severe phenotype. This genotype-phenotype correlation was also identified in six cases with recurrent missense mutations. Based on patient genotype, the severity of the disease may be predicted with high probability in approximately half of MPS II patients.

Early Presentation of Hyperinsulinism/Hyperammonemia Syndrome in Three Serbian Patients

Hyperinsulinism/hyperammonemia (HI/HA) syndrome is considered as the second most common type of hereditary HI. Correlation of genotype and phenotype in HI/HA syndrome has been described in several studies. We present three Serbian patients with HI/HA syndrome with emphasis on a possible correlation between genotype and clinical manifestations. Patient 1 was heterozygous for a de novo mutation p.S445L in the GLUD1 gene, while patients 2 and 3 (son and mother) both carry the p.R221C mutation. Early onset of hypoglycaemia with generalized seizures was recorded in infancy in all three patients. The two male patients had mild developmental delay, while the female patient presented with epilepsy. Analysis of Serbian patients with HI/HA syndrome confirms the association of p.S445L and p.R221C mutations with hypoglycaemic seizures noted within the first three months of life and with subsequent risk for cognitive impairment and/or epilepsy.

Molecular and phenotypic characteristics of seven novel mutations causing branched-chain organic acidurias

Specific mitochondrial enzymatic deficiencies in the catabolism of branched-chain amino acids cause methylmalonic aciduria (MMA), propionic acidemia (PA) and maple syrup urine disease (MSUD). Disease-causing mutations were identified in nine unrelated branched-chain organic acidurias (BCOA) patients. We detected eight previously described mutations: p.Asn219Tyr, p.Arg369His p.Val553Glyfs*17 in MUT, p.Thr198Serfs*6 in MMAA, p.Ile144_Leu181del in PCCB, p.Gly288Valfs*11, p.Tyr438Asn in BCKDHA and p.Ala137Val in BCKDHB gene. Interestingly, we identified seven novel genetic variants: p.Leu549Pro, p.Glu564*, p.Leu641Pro in MUT, p.Tyr206Cys in PCCB, p.His194Arg, p.Val298Met in BCKDHA and p.Glu286_Met290del in BCKDHB gene. In silico and/or eukaryotic expression studies confirmed pathogenic effect of all novel genetic variants. Aberrant enzymes p.Leu549Pro MUT, p.Leu641Pro MUT and p.Tyr206Cys PCCB did not show residual activity in activity assays. In addition, activity of MUT enzymes was not rescued in the presence of vitamin B12 precursor in vitro which was in accordance with non-responsiveness or partial responsiveness of patients to vitamin B12 therapy. Our study brings the first molecular genetic data and detailed phenotypic characteristics for MMA, PA and MSUD patients for Serbia and the whole South-Eastern European region. Therefore, our study contributes to the better understanding of molecular landscape of BCOA in Europe and to general knowledge on genotype-phenotype correlation for these rare diseases.

Tetrahydrobiopterin deficiency among Serbian patients presenting with hyperphenylalaninemia

Hyperphenylalaninemia (HPA) [phenylketonuria (PKU) and tetrahydrobiopterin (BH4) deficiencies] is rare inborn metabolic disease characterized by elevated phenylalanine level in body fluids. In Serbia, 62 HPA patients have been identified through newborn screening since 1983. However, pterin pattern analysis is not performed. We present a patient initially diagnosed and treated as classical PKU. At 3 years of age, during infection with H1N1 influenza A virus, the patient first developed a neurologic crisis with encephalopathy and dystonic movements. We suspected that the patient is the first case of BH4 deficiency identified in Serbia. Genetic analyses showed that the patient does not have disease-causing variants of the PAH gene and carries a p.Asp136Val mutation in homozygous state in the PTS gene. For patients with treatable rare diseases, like PKU and BH4 deficiencies, correct diagnosis is crucial for the implementation of optimal treatment. If biochemical tests needed for differential diagnosis are not available, our experience emphasizes the necessity of immediate genetic testing after newborn screening.

Epidemiology of Rett syndrome in Serbia: prevalence, incidence and survival

BACKGROUND

Rett syndrome (RTT) is a severe neurodevelopmental disorder that represents the second most common cause of mental retardation in females. However, incidence and prevalence of RTT are scarcely reported.

METHODS

A retrospective study included all patients with RTT diagnosed between 1981 and 2012 in Serbia. Estimation of incidence and prevalence was calculated on the basis of vital statistics reported by Statistical Office of Republic of Serbia.

RESULTS

From 1981 to 2012, RTT has been diagnosed in 102 girls in Serbia. Incidence of RTT in Serbia is estimated at 0.586:10,000 female live births. We estimated the prevalence of RTT in population of females younger than 19 years at 1:8,439. Death occurred in 19 patients (18.63%), with pneumonia as the most common cause. The lethal outcome by the age of 12 years could be expected for 11% of patients. The mean age at diagnosis was 3.5 years and we have confirmed a significant trend towards earlier dianosis during studied period.

CONCLUSIONS

Rett syndrome incidence in Serbia is in accordance with reports from other countries. Serbian RTT patients have increased risk for early death when compared to patients in more developed countries, most commonly due to pneumonia. There was significant trend towards early diagnosis of RTT in Serbia over recent decades.

Vitamin D deficiency in Serbian patients with Rett syndrome

INTRODUCTION

Rett syndrome (RTT) is a severe neurodevelopmental disorder. Bone manifestations of RTT include osteopenia and fractures. Studies addressing serum vitamin D levels in patients with RTT are scarce.

GOALS

The goals of this study were (1) to determine the prevalence of vitamin D deficiency in patients with RTT, (2) to compare serum vitamin D levels between patients with RTT and those with other neurological diseases, and (3) to explore the correlation between demographic and clinical characteristics of patients with RTT and vitamin D levels.

METHODS

Demographic and clinical characteristics included age, body mass index Z-score, mutation status, clinical severity score, presence of epilepsy, number of antiepileptic drugs, history of fractures, scoliosis, and ambulation ability. Laboratory parameters included serum 25-hydroxyvitamin D [25(OH)D], PTH, calcium, and alkaline phosphatase.

RESULTS

The study included 35 patients with RTT and 35 age-matched females with other neurological diseases. The median serum 25(OH)D concentration in the RTT group was 26.25 nmol/L, with values <75 nmol/L in all participants. Severe deficiency (<25 nmol/L) was detected in 17 of 35 (48.6%) patients. The median 25(OH)D concentration was significantly lower in patients with RTT than in control subjects. The risk for fracture by 12 years of age in patients with RTT was 35.3%. An inverse correlation of the 25(OH)D level to age and PTH level was detected. Patients receiving antiepileptic polytherapy had a 3.3 times greater chance for severe vitamin D deficiency than patients receiving monotherapy.

CONCLUSION

The prevalence of vitamin D deficiency in patients with RTT is higher than that in patients with other neurological diseases. The high risk for vitamin D deficiency should be accounted for in the strategy of antiepileptic treatment in RTT, especially when polytherapy is considered.

Pulmonary involvement in siblings with Gaucher disease type III

INTRODUCTION

Pulmonary involvement has been described in all types of Gaucher disease (GD) but it is considered as relatively rare manifestation. There are reports suggesting that homozygosity for L444P mutation in GBA gene is associated with a substantial risk for developing primary pulmonary disease in GD.

CASE REPORT

We reported sisters with pulmonary involvement in GD type III. Respiratory failure with fatal outcome at 3 years and 4 months of age occurred in K.K. due to pulmonary complications of GD. At the time enzyme replacement therapy (ERT) was not available in Serbia. J.K., homozygous for L444P mutation, developed asymptomatic pulmonary involvement at the age of 6 after 2.5 years of ERT. Pulmonary disease in J.K. was verified by high resolution computerized tomography, cytology of bronchoalveolar lavage fluid and histopathology of transbronchial lung biopsy.

CONCLUSION

Primary lung disease in children homoallelic for L444P mutation in GBA gene emerges as a significant clinical manifestation of GD with unclear response to ERT.

Social context of marijuana use among the young population: Case of Serbia

Introduction

Global socio-cultural and family context of Serbian society intensifies risks of marijuana use (MU).

Objectives

Prevalence of MU in young population in Serbia and identification of family factors related to increased risk of MU.

Aim

Five indicators were examined: prevalence of MU, age of first MU, MU during one month before survey, motives for MU, family factors of risk for MU.

Method

The study included 2987 participants aged between 16 and 35 years from different parts of Serbia. Collection of data was conducted in April 2007. Participants completed self-administered anonymous questionnaires (modified YOUTH RISK BEHAVIOUR SURVEY) that consisted of sociodemographic characteristics and experiences related to MU.

Results

The prevalence of lifetime MU among participants was 32%. First use was reported by 14% to occur at the age of sixteen or younger. During one month before survey 10% of participants had smoked marijuana. Risk of MU in regular cigarette smokers is two-fold higher than in non-smokers. Key motives for MU are curiosity (59%), achieving “good mood” (12%), persuasion by persons of the same age (11%), the emotional crisis (8,5%). Alcoholism of both parents and family dysfunctionality - especially physical and verbal conflicts between parents - were related to significantly higher risk of marijuana use.

Conclusion

Early use of marijuana, history of family disorganization, parental alcoholism and conflicts were identified as factors significantly related to increased risk of marijuana use among young population in Serbia.