Prevalence, predictors, and outcomes of major congenital anomalies: A population-based register study.

Congenital anomalies (CAs) are a leading cause of morbidity and mortality in early life. We aimed to assess the incidence, risk factors, and outcomes of major CAs in the State of Qatar. A population-based retrospective data analysis of registry data retrieved from the Perinatal Neonatal Outcomes Research Study in the Arabian Gulf (PEARL-Peristat Study) between April 2017 and March 2018. The sample included 25,204 newborn records, which were audited between April 2017 and March 2018, of which 25,073 live births were identified and included in the study. Maternal risk factors and neonatal outcomes were assessed for association with specific CAs, including chromosomal/genetic, central nervous system (CNS), cardiovascular system (CVS), facial, renal, multiple congenital anomalies (MCAs) using univariate and multivariate analyses. The incidence of any CA among live births was 1.3% (n = 332). The most common CAs were CVS (n = 117; 35%), MCAs (n = 69, 21%), chromosomal/genetic (51; 15%), renal (n = 39; 12%), CNS (n = 20; 6%), facial (14, 4%), and other (GIT, Resp, Urogenital, Skeletal) (n = 22, 7%) anomalies. Multivariable regression analysis showed that multiple pregnancies, parity ≥ 1, maternal BMI, and demographic factors (mother's age and ethnicity, and infant's gender) were associated with various specific CAs. In-hospital mortality rate due to CAs was estimated to be 15.4%. CAs were significantly associated with high rates of caesarean deliveries (aOR 1.51; 95% CI 1.04-2.19), Apgar < 7 at 1 min (aOR 5.44; 95% CI 3.10-9.55), Apgar < 7 at 5 min (aOR 17.26; 95% CI 6.31-47.18), in-hospital mortality (aOR 76.16; 37.96-152.8), admission to neonatal intensive care unit (NICU) or perinatal death of neonate in labor room (LR)/operation theatre (OT) (aOR 34.03; 95% CI 20.51-56.46), prematurity (aOR 4.17; 95% CI 2.75-6.32), and low birth weight (aOR 5.88; 95% CI 3.92-8.82) before and after adjustment for the significant risk factors. This is the first study to assess the incidence, maternal risk factors, and neonatal outcomes associated with CAs in the state of Qatar. Therefore, a specialized congenital anomaly data registry is needed to identify risk factors and outcomes. In addition, counselling of mothers and their families may help to identify specific needs for pregnant women and their babies.

Incidence, risk factors, and feto-maternal outcomes of inappropriate birth weight for gestational age among singleton live births in Qatar: A population-based study.

BACKGROUND: Abnormal fetal growth can be associated with factors during pregnancy and at postpartum. OBJECTIVE: In this study, we aimed to assess the incidence, risk factors, and feto-maternal outcomes associated with small-for-gestational age (SGA) and large-for-gestational age (LGA) infants. METHODS: We performed a population-based retrospective study on 14,641 singleton live births registered in the PEARL-Peristat Study between April 2017 and March 2018 in Qatar. We estimated the incidence and examined the risk factors and outcomes using univariate and multivariate analysis. RESULTS: SGA and LGA incidence rates were 6.0% and 15.6%, respectively. In-hospital mortality among SGA and LGA infants was 2.5% and 0.3%, respectively, while for NICU admission or death in labor room and operation theatre was 28.9% and 14.9% respectively. Preterm babies were more likely to be born SGA (aRR, 2.31; 95% CI, 1.45-3.57) but male infants (aRR, 0.57; 95% CI, 0.4-0.81), those born to parous (aRR 0.66; 95% CI, 0.45-0.93), or overweight (aRR, 0.64; 95% CI, 0.42-0.97) mothers were less likely to be born SGA. On the other hand, males (aRR, 1.82; 95% CI, 1.49-2.19), infants born to parous mothers (aRR 2.16; 95% CI, 1.63-2.82), or to mothers with gestational diabetes mellitus (aRR 1.36; 95% CI, 1.11-1.66), or pre-gestational diabetes mellitus (aRR 2.58; 95% CI, 1.8-3.47) were significantly more likely to be LGA. SGA infants were at high risk of in-hospital mortality (aRR, 226.56; 95% CI, 3.47-318.22), neonatal intensive care unit admission or death in labor room or operation theatre (aRR, 2.14 (1.36-3.22). CONCLUSION: Monitoring should be coordinated to alleviate the risks of inappropriate fetal growth and the associated adverse consequences.

Incidence, Risk Factors, and Outcomes of Preterm and Early Term Births: A Population-Based Register Study.

Preterm birth (PTB) and early term birth (ETB) are associated with high risks of perinatal mortality and morbidity. While extreme to very PTBs have been extensively studied, studies on infants born at later stages of pregnancy, particularly late PTBs and ETBs, are lacking. In this study, we aimed to assess the incidence, risk factors, and feto-maternal outcomes of PTB and ETB births in Qatar. We examined 15,865 singleton live births using 12-month retrospective registry data from the PEARL-Peristat Study. PTB and ETB incidence rates were 8.8% and 33.7%, respectively. PTB and ETB in-hospital mortality rates were 16.9% and 0.2%, respectively. Advanced maternal age, pre-gestational diabetes mellitus (PGDM), assisted pregnancies, and preterm history independently predicted both PTB and ETB, whereas chromosomal and congenital abnormalities were found to be independent predictors of PTB but not ETB. All groups of PTB and ETB were significantly associated with low birth weight (LBW), large for gestational age (LGA) births, caesarean delivery, and neonatal intensive care unit (NICU)/or death of neonate in labor room (LR)/operation theatre (OT). On the other hand, all or some groups of PTB were significantly associated with small for gestational age (SGA) births, Apgar < 7 at 1 and 5 min and in-hospital mortality. The findings of this study may serve as a basis for taking better clinical decisions with accurate assessment of risk factors, complications, and predictions of PTB and ETB.

Natural history, with clinical, biochemical, and molecular characterization of classical homocystinuria in the Qatari population.

Classical homocystinuria (HCU) is the most common inborn error of metabolism in Qatar, with an incidence of 1:1800, and is caused by the Qatari founder p.R336C mutation in the CBS gene. This study describes the natural history and clinical manifestations of HCU in the Qatari population. A single center study was performed between 2016 and 2017 in 126 Qatari patients, from 82 families. Detailed clinical and biochemical data were collected, and Stanford-Binet intelligence, quality of life and adherence to treatment assessments were conducted prospectively. Patients were assigned to one of three groups, according to the mode of diagnosis: (a) late diagnosis group (LDG), (b) family screening group (FSG), and (c) newborn screening group (NSG). Of the 126 patients, 69 (55%) were in the LDG, 44 (35%) in the NSG, and 13 (10%) in the FSG. The leading factors for diagnosis in the LDG were ocular manifestations (49%), neurological manifestations (45%), thromboembolic events (4%), and hyperactivity and behavioral changes (1%). Both FSG and NSG groups were asymptomatic at time of diagnosis. NSG had significantly higher intelligence quotient, quality of life, and adherence values compared with the LDG. The LDG and FSG had significantly higher methionine levels than the NSG. The LDG also had significantly higher total homocysteine levels than the NSG and FSG. Regression analysis confirmed these results even when adjusting for age at diagnosis, current age, or adherence. These findings increase the understanding of the natural history of HCU and highlight the importance of early diagnosis and treatment. SYNOPSIS: A study in 126 Qatari patients with HCU, including biochemical, clinical, and other key assessments, reveals that patients with a late clinical diagnosis have a poorer outcome, hereby highlighting the importance of early diagnosis and treatment.

Diagnosis of Carnitine Deficiency in Extremely Preterm Neonates Related to Parenteral Nutrition: Two Step Newborn Screening Approach.

Currently, there is no evidence in the literature to support the routine supplementation of all parenterally fed premature infants with l-carnitine. In our study, we found that about 8.56% of extremely preterm neonates are diagnosed with carnitine deficiency secondary to malnutrition, either due to reduced stores at birth or related to total parenteral nutrition (TPN). Our two step approach of performing newborn screening (NBS) again at 32 weeks gestational age (GA) equivalent helps to diagnose 81.4% more preterm babies with carnitine deficiency-who would otherwise be missed-and supplement them with l-carnitine for optimal growth. We performed a retrospective cohort study to diagnose carnitine deficiency related to malnutrition in two groups: those presenting at birth and those presenting later in life. We found that there was a statistically significant difference in the median GA and birth weight (BW) between the two groups, but there was no difference in the free carnitine levels.

Human heterologous liver cells transiently improve hyperammonemia and ureagenesis in individuals with severe urea cycle disorders.

BACKGROUND: Urea cycle disorders (UCDs) still have a poor prognosis despite several therapeutic advancements. As liver transplantation can provide a cure, liver cell therapy (LCT) might be a new therapeutic option in these patients. METHODS: Twelve patients with severe UCDs were included in this prospective clinical trial. Patients received up to six infusions of cryopreserved human heterologous liver cells via a surgically placed catheter in the portal vein. Portal vein pressure, portal vein flow, and vital signs were monitored continuously. Calcineurin inhibitors and steroids were used for immunosuppression. In four patients, ureagenesis was determined with stable isotopes. Number and severity of hyperammonemic events and side effects of immunosuppression were analyzed during an observation period of up to 2 years. RESULTS: No study-related mortality was observed. The application catheter dislocated in two children. No significant side effects of catheter application or cell infusion were noted in the other ten patients. The overall incidence of infections did not differ significantly from a historical control group, and no specific side effects of immunosuppression were found. Seven patients were treated per protocol and could be analyzed for efficacy. Severe metabolic crises could be prevented in all of these patients, moderate crises in four of seven. Ureagenesis increased after cell infusion in all patients investigated. CONCLUSIONS: We found a favorable safety profile with respect to catheter placement, intraportal liver cell infusion, and immunosuppression. More than half of the children treated per protocol experienced metabolic stabilization and could be safely bridged to liver transplantation.

Newborn screening for remethylation disorders and vitamin B12 deficiency-evaluation of new strategies in cohorts from Qatar and Germany.

BACKGROUND: Newborn screening is a precondition for early diagnosis and successful treatment of remethylation disorders and classical homocystinuria (cystathionine-ß-synthase deficiency). Newborn screening for classical homocystinuria using total homocysteine measurement in dried blood spots has been very successfully performed for many years for newborns from Qatar. METHODS: A new optimized newborn screening strategy for remethylation disorders and homocystinuria was developed and evaluated for newborns from Qatar using total homocysteine measurement as first-tier and methionine, methionine-phenylalanine-ratio and propionylcarnitine as second-tiers. Proposed cut-offs were also retrospectively evaluated in newborn screening samples of 12 patients with remethylation disorders and vitamin B12 deficiency from Qatar and Germany. RESULTS: Over a 12 months period, the proposed strategy led to a decrease in the recall rate in homocysteine screening for Qatar from 1.09% to 0.68%, while allowing for additional systematic inclusion of remethylation disorders and vitamin B12 deficiency into the screening panel for Qatar. In the evaluated period the applied strategy would have detected all patients with classical homocystinuria identified by the previous strategy and in addition 5 children with maternal nutritional vitamin B12 deficiency and one patient with an isolated remethylation disorder. Additional retrospective evaluation of newborn screening samples of 12 patients from Germany and Qatar with remethlyation disorders or vitamin B12 deficiency showed that all of these patients would have been detected by the cut-offs used in the proposed new strategy. In addition, an adapted strategy for Germany using methionine, methionine-phenylalanine-ratio and propionylcarnitine as first-tier, and homocysteine as a second-tier test was also positively evaluated retrospectively. CONCLUSIONS: The proposed strategy for samples from Qatar allows inclusion of remethylation disorders and vitamin B12 deficiency in the screening panel, while lowering the recall rate. An adapted second-tier strategy is presented for screening in Germany and will be prospectively evaluated over the next years in a pilot project named "Newborn Screening 2020".

Newborn Screening for Vitamin B6 Non-responsive Classical Homocystinuria: Systematical Evaluation of a Two-Tier Strategy.

BACKGROUND: In classical homocystinuria (HCU, MIM# 236200) due to the deficiency of cystathionine ß-synthase (EC 4.2.1.22) there is a clear evidence for the success of early treatment. The aim of this study was to develop and evaluate a two-tier strategy for HCU newborn screening. METHODS: We reevaluated data from our newborn screening programme for Qatar in a total number of 125,047 neonates including 30 confirmed HCU patients. Our hitherto existing screening strategy includes homocysteine (Hcy) measurements in every child, resulting in a unique dataset for evaluation of two-tier strategies. Reevaluation included methionine (Met) levels, Met to phenylalanine (Phe) ratio, and Hcy. Four HCU cases identified after database closure were also included in the evaluation. In addition, dried blood spot samples selected by Met values >P97 in the newborn screening programs in Austria, Australia, the Netherlands, and Taiwan were analyzed for Hcy. RESULTS: Met to Phe ratio was found to be more effective for first sieve than Met, sorting out nearly 90% of normal samples. Only 10% of the samples would have to be processed by second-tier measurement of Hcy in dried blood spots. As no patient with HCU was found neither in the samples investigated for HCU, nor by clinical diagnosis in the other countries, the generalization of our two-tier strategy could only be tested indirectly. CONCLUSION: The finally derived two-tier algorithm using Met to Phe ratio as first- and Hcy as second-tier requires 10% first-tier positives to be transferred to Hcy measurement, resulting in 100% sensitivity and specificity in HCU newborn screening.

Gestational age specific neonatal survival in the State of Qatar (2003-2008) - a comparative study with international benchmarks.

OBJECTIVE: To analyze and compare the current gestational age specific neonatal survival rates between Qatar and international benchmarks. STUDY DESIGN: An analytical comparative study. PLACE AND DURATION OF STUDY: Women's Hospital, Hamad Medical Corporation, Doha, Qatar, from 2003-2008. METHODOLOGY: Six year's (2003-2008) gestational age specific neonatal mortality data was stratified for each completed week of gestation at birth from 24 weeks till term. The data from World Health Statistics by WHO (2010), Vermont Oxford Network (VON, 2007) and National Statistics United Kingdom (2006) were used as international benchmarks for comparative analysis. RESULTS: A total of 82,002 babies were born during the study period. Qatar's neonatal mortality rate (NMR) dropped from 6/1000 in 2003 to 4.3/1000 in 2008 (p < 0.05). The overall and gestational age specific neonatal mortality rates of Qatar were comparable with international benchmarks. The survival of < 27 weeks and term babies was better in Qatar (p=0.01 and p < 0.001 respectively) as compared to VON. The survival of > 32 weeks babies was better in UK (p=0.01) as compared to Qatar. The relative risk (RR) of death decreased with increasing gestational age (p < 0.0001). Preterm babies (45%) followed by lethal chromosomal and congenital anomalies (26.5%) were the two leading causes of neonatal deaths in Qatar. CONCLUSION: The current total and gestational age specific neonatal survival rates in the State of Qatar are comparable with international benchmarks. In Qatar, persistently high rates of low birth weight and lethal chromosomal and congenital anomalies significantly contribute towards neonatal mortality.

Newborn population screening for classic homocystinuria by determination of total homocysteine from Guthrie cards.

OBJECTIVE: To allow early recognition of cystathionine beta-synthase by newborn screening. STUDY DESIGN: Total homocysteine was determined in dried blood spots with a novel, robust high-performance liquid chromatography method with tandem mass spectrometry. Quantification of homocysteine was linear over a working range up to 50 micromol/L. For mutation analysis, DNA was tested for 2 mutations common in Qatar. RESULTS: Both methods proved to be suitable for high throughput processing. In 2 years, 7 infants with classic homocystinuria were identified of 12,603 native Qatari infants, yielding an incidence of 1:1800. Molecular screening would have missed 1 patient homozygous for a mutation not previously identified in the Qatari population. Over a period of 3 years, a total of 14 cases of classic homocystinuria were detected by screening of homocysteine from all newborn infants born in Qatar (n = 46 406). Homocysteine was always elevated, whereas methionine was elevated in only 7 cases. CONCLUSIONS: The study offers a reliable method for newborn screening for cystathionine beta-synthase deficiency, reaching a sensitivity of up to 100%, even if samples are taken within the first 3 days of life.

Molecular neonatal screening for homocystinuria in the Qatari population.

We report the results of molecular neonatal screening for homocystinuria (cystathionine beta-synthase deficiency) in neonates of Qatari origin, developed in conjunction with a novel biochemical screening approach. DNA was extracted from dried blood spots (DBS); the prevalent Qatari CBS gene mutation p.R336C (c.1006C>T) and a second mutation were tested with specific TaqMan assays. Over a period of 2 years we screened 12,603 neonates and identified six affected neonates homozygous for p.R336C. There were 225 heterozygous carriers for p.R336C. One additional child with homocystinuria detected through biochemical screening was homozygous for a mutation not previously identified in Qatar. Homocystinuria in the Qatari population has an incidence of 1:1,800, the highest in the world and even higher than previously estimated. Allele frequency of the mutation p.R336C is approximately 1%, displaying a significant deviation from Hardy Weinberg equilibrium. In conclusion, first-line molecular neonatal screening is technically feasible and may be developed as an option for presymptomatic identification of genetic disorders caused by specific mutations or a limited number of prevalent mutations. However, sensitivity for the diagnosis of disorders caused by various mutations is limited even in a homogeneous population such as Qatar.

Are heterocygotes for classical homocystinuria at risk of vitamin B12 and folic acid deficiency?

OBJECTIVES/DESIGN: Comparative cross-sectional study to assess homocysteine and vitamin status in carriers of CBS gene mutations. METHOD: Subjects included 34 parents (13 males, 21 females, age 27-59 years) of 30 patients with classical homocystinuria due to homozygous cystathionine beta-synthase deficiency. Control subjects were matched for gender and age (13 males, 21 females, age 25-59 years). All subjects were of Qatari origin, had normal liver and renal function tests and had not taken drugs or vitamin supplements prior to the study. The concentrations of homocysteine, folic acid and vitamins B6 and B12 in blood were determined after an overnight fast. RESULTS: Heterozygous carriers had significantly increased fasting levels of homocysteine compared to controls (9.1 vs. 8.1 micromol/l, P=0.012). Both folic acid (328 vs. 478 pmol/l, P=0.002) and vitamin B12 concentrations (232 vs. 287 pmol/l, P=0.013) were reduced whilst there was no significant difference in vitamin B6 levels between the two groups (5.8 vs. 6.44 microg/l). CONCLUSIONS: Increased homocysteine concentrations in CBS gene mutation carriers are associated with reduced concentrations of folic acid and vitamin B12 in blood. In view of the adverse effects of mild hyperhomocysteinemia, routine testing of vitamin status in parents of homocystinuria patients may be warranted. The causal relationship and pathophysiological consequences are uncertain; it is likely that CBS gene mutation carriers need higher doses of dietary vitamins.