Neonatal thrombo-embolism: risk factors, clinical features and outcome

Association between Portal Vein Thrombosis after Umbilical Vein Catheterization and Neonatal Asphyxia

INTRODUCTION

Neonatal portal vein thrombosis (PVT) is frequently related to umbilical venous catheterization (UVC), but risk factors remain unclear. This study aims to analyze the variables associated to PVT in near- to full-term newborns with UVC, with a focus on newborns exposed to controlled therapeutic hypothermia (CTH) for hypoxic ischemic encephalopathy (HIE).

METHODS

This is retrospective cohort study of infants delivered at or after 36 weeks and with a birthweight over 1,500 g. All infants were assessed for UVC location and PVT using ultrasonography performed between day 5 and day 10 after catheterization.

RESULTS

Among 213 eligible patients, PVT was diagnosed in 57 (27%); among them, 54 (95%) were localized in the left portal vein branch. With all significant factors in univariate analysis considered, higher gestational age at birth (adjusted OR 1.35; 95% CI: 1.12-1.64, p = 0.002) and duration of UVC placement (adjusted OR 1.36; 95% CI: 1.11-1.67, p = 0.004) were the main risk factors of PVT. Among 87 infants who were cooled for HIE, 31 (36%) had PVT compared to 26 (21%) in infants without CTH. Using a multivariate model including variables linked to treatment procedures only, an increased PVT incidence was statistically associated with UVC duration (adjusted OR 1.33; 95% CI: 1.08; 1.63, p = 0.01) and CTH (adjusted OR 1.94; 95% CI: 1.04-3.65, p = 0.04).

CONCLUSION

Left PVT was frequently observed in near- to full-term neonates with UVC. Among factors linked to treatment procedures, both duration of UVC and CTH exposure for HIE were found to be independent risk factors of PVT.

Risk factors for venous thromboembolism in a single pediatric intensive care unit in China

BACKGROUND

Analyses of extensive, nationally representative databases indicate a rising prevalence of venous thromboembolism (VTE) among critically ill children. However, the majority of studies on childhood VTE have primarily concentrated on Caucasian populations in the United States and European countries. There is a lack of epidemiological studies on VTE in Chinese children.

METHODS

We conducted a retrospective cohort study of data from the Pediatric Intensive Care (PIC) database. Data were obtained and extracted by using Structured Query Language (SQL) and the administrative platform pgAdmin4 for PostgreSQL. Bivariate analyses were conducted in which categorical variables were analyzed by a chi-square test and continuous variables were analyzed by a Student's t-test. Separate multivariable logistic regressions were employed to investigate the associations between VTE and sociodemographic factors as well as clinical factors.

RESULTS

Our study included 12,881 pediatric patients from the PIC database, spanning the years 2010 to 2018. The incidence rate of pediatric VTE was 0.19% (24/12,881). The venous thrombotic locations were deep venous thrombosis extremities (n = 18), superior vena cava (n = 1), cerebral sinovenous (n = 1), and other deep venous thrombosis (n = 4). Univariate analysis showed that age, weight, shock, sepsis, cancer and vasopressor receipt were statistically significant risk factors for pediatric VTE (all p ≤ 0.05). After multivariable logistic regression analysis, only shock (aOR: 6.77, 95%CI: 1.33-34.73, p = 0.019) and admission for sepsis (aOR: 6.09, 95%CI: 1.76-21.09, p = 0.004) were statistically significant associated with pediatric VTE.

CONCLUSIONS

In conclusion, data obtained from the Pediatric Intensive Care (PIC) database revealed a prevalence of VTE in pediatric patients of 0.19%. The most common location for venous thrombi was deep venous thrombosis (DVT) in the extremities. We identified that shock and sepsis were statistically significant factors associated with pediatric VTE.

Neonatal portal vein thrombosis: risk factors, diagnosis, treatment recommendations and review of the literature

BACKGROUND

Neonatal portal vein thrombosis (PVT) is currently more commonly encountered as a result of advances in diagnostic tools and increase in invasive interventions.

METHODS

In this study, 11 premature and 12 term infants diagnosed with PVT were retrospectively evaluated for clinical and laboratory characteristics, umbilical catheterization procedure, PVT location, risk factors, treatments, and long-term outcomes.

RESULTS

Median age of the patients at diagnosis was 10 days (range 3-90 days), and 69.6% of patients were girls. Of the 23 patients, 87% had left PVT and, 91.3% had at least one thrombosis risk factor, which was sepsis in 73.9% of patients, and presence of umbilical venous catheter in 87%. Totally, 59.1% of PVTs were completely resolved in a median follow-up of 7 months (1 month to 12 months), and 78.3% of these patients had no anticoagulant therapy (ACT). Partial thrombus resolution was achieved in 9 patients (40.9%). Five patients (%21) received ACT. Overall, 34.8% of patients had long-term complications. neonatal PVT is most commonly reported in the left portal vein and there is no evidence for the impact of ACT on reducing the short- or long-term complications. Well designed and larger studies are necessary to clarify this issue, which can facilitate developing appropriate management algorithms.

CONCLUSION

Neonatal PVT is most commonly reported in the left portal vein and there is no evidence for the impact of ACT on reducing the short- or long-term complications. Well designed and larger studies are necessary to clarify this issue, which can facilitate developing appropriate management algorithms.

Neonatal Myocardial Ischemia-Reperfusion Injury: A Proposed Pathogenic Sequence in the Context of Maternal/Fetal Vascular Malperfusion and Paradoxical Embolism

BACKGROUND

Neonatal myocardial infarction (MI) in a structurally normal heart is frequently an obscure event that remains undiagnosed until autopsy. Causal attributions usually cite underlying maternal or fetal conditions. Refinement in understanding of pathogenic mechanisms underlying neonatal MI is key to advancements in diagnosis, prevention, treatments and prognosis.

OBJECTIVE

This study presents a 36-week gestational age female with perinatal asphyxia, congenital hemolytic anemia and umbilical vein thrombosis who sustained catastrophic MI with reperfusion injury; and it reviews pertinent literature.

RESULTS

We propose a pathogenic sequence that links maternal vascular malperfusion, fetal vascular malperfusion, hemolytic anemia, umbilical venous thrombosis, and paradoxical thromboemboli.

CONCLUSION

This case highlights the importance of placental examination in connecting complex neonatal events with adverse maternal/placental conditions. A high index of suspicion is essential for early diagnosis of neonatal MI.

Venous Thromboembolism in Premature Neonates

While the incidence of venous thromboembolism (VTE) is lower among children than adults, the newborn period is one of two bimodal peaks (along with adolescence) in VTE incidence in the pediatric population. Most VTE cases in neonates occur among critically ill neonates being managed in the neonatal intensive care unit, and most of these children are born premature. For this reason, the presentation, diagnosis, management, and outcomes of VTE among children born premature deserve special emphasis by pediatric hematologists, neonatologists, pharmacists, and other pediatric health care providers, as well as by the scientific community, and are described in this review.

Incidence of umbilical vein catheter-associated thrombosis of the portal system: A systematic review and meta-analysis

BACKGROUND

The use of umbilical venous catheters (UVCs) in the perinatal period may be associated with severe complications, including the occurrence of portal vein thrombosis (PVT).

AIM

To assess the incidence of UVC-related PVT in infants with postnatal age up to three months.

METHODS

A systematic and comprehensive database searching (PubMed, Cochrane Library, Scopus, Web of Science) was performed for studies from 1980 to 2020 (the search was last updated on November 28, 2020). We included in the final analyses all peer-reviewed prospective cohort studies, retrospective cohort studies and case-control studies. The reference lists of included articles were hand-searched to identify additional studies of interest. Studies were considered eligible when they included infants with postnatal age up to three months with UVC-associated PVT. Incidence estimates were pooled by using random effects meta-analyses. The quality of included studies was assessed using the Newcastle-Ottawa scale. The systematic review was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines.

RESULTS

Overall, 16 studies were considered eligible and included in the final analyses. The data confirmed the relevant risk of UVC-related thrombosis. The mean pooled incidence of such condition was 12%, although it varied across studies (0%-49%). In 15/16 studies (94%), diagnosis of thrombosis was made accidentally during routine screening controls, whilst in 1/16 study (6%) targeted imaging assessments were carried out in neonates with clinical concerns for a thrombus. Tip position was investigated by abdominal ultrasound (US) alone in 1/16 (6%) studies, by a combination of radiography and abdominal US in 14/16 (88%) studies and by a combination of radiography, abdominal US and echocardiography in 1/16 (6%) studies.

CONCLUSION

To the best of our knowledge, this is the first systematic review specifically investigating the incidence of UVC-related PVT. The use of UVCs requires a high index of suspicion, because its use is significantly associated with PVT. Well-designed prospective studies are required to assess the optimal approach to prevent UVC-related thrombosis of the portal system.

Childhood risk factors for adulthood chronic kidney disease

Chronic kidney disease (CKD) is a major public health challenge, affecting as much as 8 to 18% of the world population. Identifying childhood risk factors for future CKD may help clinicians make early diagnoses and initiation of preventive interventions for CKD and its attendant comorbidities as well as monitoring for complications. The purpose of this review is to describe childhood risk factors that may predict development of overt kidney disease later in life. Currently, there are multiple childhood risk factors associated with future onset and progression of CKD. These risk factors can be grouped into five categories: genetic factors (e.g., monogenic or risk alleles), perinatal factors (e.g., low birth weight and prematurity), childhood kidney diseases (e.g., congenital anomalies, glomerular diseases, and renal cystic ciliopathies), childhood onset of chronic conditions (e.g., cancer, diabetes, hypertension, dyslipidemia, and obesity), and different lifestyle factors (e.g., physical activity, diet, and factors related to socioeconomic status). The available published information suggests that the lifelong risk for CKD can be attributed to multiple factors that appear already during childhood. However, results are conflicting on the effects of childhood physical activity, diet, and dyslipidemia on future renal function. On the other hand, there is consistent evidence to support follow-up of high-risk groups.

Risk factors for umbilical vascular catheter-related adverse events: A scoping review

INTRODUCTION

Adverse events associated with umbilical catheters include malposition, bloodstream infections, thrombosis, tip migration, and extravasation, resulting in loss of vascular access and increased risk of morbidity and mortality. There is a need for greater understanding of risk factors associated with adverse events to inform safe practice.

OBJECTIVES

The aim of the study was to summarise the existing evidence regarding risk factors for umbilical catheter-related adverse events to inform the undertaking of future research.

REVIEW METHOD USED

A scoping review of peer-reviewed original research and theses was performed.

DATA SOURCES

The US National Library of Medicine National Institutes of Health, Embase, EMcare, and ProQuest Dissertations and Theses were the data sources.

REVIEW METHODS

Informed by the Joanna Briggs Institute Reviewer's Manual, all types of original research studies reporting adverse events published in English from 2009 to 2020 were eligible for inclusion. Studies where umbilical artery catheter and umbilical venous catheter data could not be extracted separately were excluded.

RESULTS

Searching identified 1954 publications and theses, 1533 were excluded at screening, and 418 were assessed for eligibility at full text. A total of 89 studies met the inclusion criteria. A range of potential risk factors for umbilical arterial and venous catheters were identified. Longer dwell time and prematurity were associated with increased risk of bloodstream infection and thrombosis in cohort studies. Case studies detailed analogous factors such as insertion techniques and lack of catheter surveillance during dwell warrant further investigation.

CONCLUSIONS

We identified a vast range of patient, device, and provider risk factors that warrant further investigation. There was a lack of large cohort studies and randomised controlled trials to demonstrate the significance of these risk factors. Improvement in methods to ensure correct catheter tip location and to detect adverse events early is essential. In addition, policy needs to be developed to guide clinicians in catheter surveillance measures to reduce the risk of adverse events.

A fern frond-like peripheral portal vein thrombosis in a neonate: A case report

Although the ultrasonographic (US) features of portal vein thrombosis in premature newborns have been described, there are very few reports on thrombosis of the peripheral branches of the portal vein. Here, I describe a case of peripheral portal vein branch thrombosis in a neonate, appearing on US imaging with a fern frond pattern.

Epidemiology of thrombosis in Canadian neonatal intensive care units

OBJECTIVE

To assess the rate, location, risk factors, management, and outcomes of neonatal thrombosis (NT).

DESIGN

A retrospective study investigating infants admitted to NICUs in Canadian Neonatal Network between January 2014 and December 2016 and diagnosed with NT. Each infant with NT was matched with an infant without NT.

RESULTS

Of 39,971 infants, 587 (1.5%) were diagnosed with NT: 440 (75%) venous, 112 (19%) arterial, 29 (5%) both. NT rate was 1.4% in full-term and 1.7% in preterm infants. Venous thrombi occurred most commonly in the portal vein and arterial thrombi in the cerebral artery. Conservative management and low molecular weight heparin were the most common treatment modalities. Hospital stay was longer (p < 0.001) in the NT patients, but mortality was similar.

CONCLUSIONS

NT was diagnosed in ~15/1000 NICU admissions and most commonly in the portal vein and cerebral arteries. Management varied based on the type and location of thrombi. Large multicenter trials are needed to address the best management strategies.

Outcomes following neonatal portal vein thrombosis: A descriptive, single-center study and review of anticoagulant therapy

BACKGROUND

Neonatal portal vein thrombosis (PVT) is uncommon with potentially serious complications that may manifest in infancy and childhood.

OBJECTIVE

The primary aim of our study was to describe the short-term and long-term outcomes of neonatal PVT.

METHODS

A retrospective chart review was conducted from 2008 to 2016 of neonates diagnosed with PVT. A systematic review was also performed from 2000 to 2018 to evaluate anticoagulant therapy (ACT) in neonatal PVT.

RESULTS

Forty-four premature and 30 term infants (mean gestational age 30.7 vs 39.1 weeks, respectively) had PVT. Sixty-eight involved the left portal vein, one involved only the main portal vein, and 5 involved ≥1 vein. PVT was catheter associated in 46 (62%); none of the 7 neonates tested had thrombophilia. Of 74 neonates, 19 (26%) received ACT and 55 (74%) were untreated. The mean follow-up duration was 16.6 months (SD = 17.62; range, 0-89.6); 59.5% were followed for ≥6 months. On last ultrasound examination, thrombus resolution was documented in treated (ACT; n = 19) and nontreated (n = 55) neonates: 12 (63%) versus 32 (58%) with complete resolution, 1 (5%) versus 6 (11%) partial, 0 versus 1 (2%) extension, and 6 (32%) versus 16 (29%) had nonprogressive lesions, respectively. Seventy-one (96%) had no complications. Seventy-one articles met inclusion criteria for the systematic review and 19 were retained for analysis after assessment.

CONCLUSIONS

PVT resolution rate was similar to previous reports. Although a low complication rate was detected, longer follow-up is necessary to determine the need for early treatment and the precise incidence of outcomes such as portal hypertension.

Risk Factors for Neonatal Venous and Arterial Thromboembolism in the Neonatal Intensive Care Unit-A Case Control Study

OBJECTIVE

To identify risk factors associated with venous and arterial thrombosis in sick neonates admitted to the neonatal intensive care unit.

STUDY DESIGN

A case-control study was conducted at 2 centers between January 2010 and March 2014 using the Children's Hospital Neonatal Database dataset. Cases were neonates diagnosed with either arterial or venous thrombosis during their neonatal intensive care unit stay; controls were matched in a 1:4 ratio by gestational age and presence or absence of central access devices. Bivariable and conditional logistic regression analyses for venous and arterial thrombosis were performed separately.

RESULTS

The overall incidence of neonatal thrombosis was 15.0 per 1000 admissions. A higher proportion of neonates with thrombosis had presence of central vascular access devices (75% vs 49%; P < .01) were of extremely preterm gestational age (22-27 weeks; 26% vs 15.0%; P <.05) and stayed ≥31 days in the neonatal intensive care unit (53% vs 32.9%; P <.01), when compared with neonates without thrombosis. A final group of 64 eligible patients with thrombosis and 4623 controls were analyzed. In a conditional multivariable logistic regression model, venous thrombosis was significantly associated with male sex (AOR, 2.12; 95% CI, 1.03-4.35; P = .04) and blood stream infection (AOR, 3.47; 95% CI, 1.30-9.24; P = .01).

CONCLUSIONS

The incidence of thrombosis was higher in our neonatal population than in previous reports. After matching for central vascular access device and gestational age, male sex and blood stream infection represent independent risk factors of neonatal venous thrombosis. A larger cohort gleaned from multicenter data should be used to confirm the study results and to develop thrombosis prevention strategies.

Inherited Thrombophilia in Pediatric Venous Thromboembolic Disease: Why and Who to Test

Venous thromboembolic disease in childhood is a multifactorial disease. Risk factors include acquired clinical risk factors such as a central venous catheter and underlying disease and inherited thrombophilia. Inherited thrombophilia is defined as a genetically determined tendency to develop venous thromboembolism. In contrast to adults, acquired clinical risk factors play a larger role than inherited thrombophilia in the development of thrombotic disease in children. The contributing role of inherited thrombophilia is not clear in many pediatric thrombotic events, especially catheter-related thrombosis. Furthermore, identification of inherited thrombophilia will not often influence acute management of the thrombotic event as well as the duration of anticoagulation. In some patients, however, detection of inherited thrombophilia may lead to identification of other family members who can be counseled for their thrombotic risk. This article discusses the potential arguments for testing of inherited thrombophilia, including factor V Leiden mutation, prothrombin mutation, and deficiencies of antithrombin, protein C, or protein S and suggests some patient groups in childhood, which may be tested.

Venous Thromboembolism in Adolescents

The incidence of venous thromboembolism (VTE) during childhood is low with two peaks – neonatal and adolescent age. This retrospective study is focused on clinical characteristics of VTE during adolescence. The main goals are to assess the most frequent inherited and acquired risk factors and to evaluate the benefit of D-dimers in diagnostics of venous thromboemblism. The data of 18 adolescents were analysed – 16 girls (88.9%), 2 boys (11.1%). In 9 patients (50%) thrombosis of the lower limb deep veins was diagnosed, six patients (33.3%) suffered from symptomatic pulmonary embolism (PE) and 3 patients (16.7%) from thrombosis at unusual sites. One patient had an idiopathic VTE, the mean number of the inherited and acquired risk factors was 2.6. The most frequent inherited risk factor was Leiden mutation of factor V (27.8%). The most frequent acquired risk factor was oral contraception (OC) in 12 out of 16 girls (75%). All of our patients on oral contraception had one or more additional risk factors. 10 out of 18 (55.6%) patients with VTE had elevated activity of factor VIII. The sensitivity of D-dimers was low (50%) in patients with distal lower limb thrombosis, but very high (100%) in patients with PE.

Manifestations and clinical impact of pediatric inherited thrombophilia

The etiology of pediatric venous thromboembolic disease (VTE) is multifactorial, and in most children, 1 or more clinical risk factors are present. In addition, inherited thrombophilic disorders contribute to the development of pediatric VTE. In this review, the role of inherited thrombophilic disorders in the development of pediatric VTE, as well as the benefits and limitations of thrombophilia testing, will be discussed.

Risk factors for hospital-sssociated venous thromboembolism in the neonatal intensive care unit

OBJECTIVE

To determine hospital-associated venous thromboembolism (HA-VTE) risk factors in critically ill neonates.

METHODS

We conducted a case-control study in the neonatal intensive care unit (NICU) of All Children's Hospital Johns Hopkins Medicine (St. Petersburg, FL), from January 1, 2006 - April 10, 2013. We identified HA-VTE cases using electronic health record. Four NICU controls were randomly selected for each HA-VTE case. Associations between putative risk factors and HA-VTE were estimated using odds ratios (ORs) and ninety-five percent confidence intervals (95%CIs) from univariate and multivariate regression analyses.

RESULTS

Twenty-three HA-VTE cases and 92 controls were included. The annual HA-VTE incidence was approximately 1.4 HA-VTE cases per 1,000 NICU admissions. In univariate analyses, mechanical ventilation (OR=7.27, 95%CI=2.02-26.17, P=0.002), central venous catheter (CVC; OR=52.95, 95%CI=6.80-412.71, P<0.001), infection (OR=7.24, 95%CI=2.66-19.72, P<0.001), major surgery (OR=5.60, 95%CI=1.82-17.22, P=0.003) and length of stay ≥15days (OR=6.67, 95%CI=1.85-23.99, P=0.004) were associated with HA-VTE. Only CVC (OR=29.04, 95%CI=3.18-265.26, P=0.003) remained an independent risk factor in the multivariate analysis. Based on this result, the estimated risk of HA-VTE in NICU patients with a CVC was 0.9%.

CONCLUSION

This study identifies CVC as an independent risk factor for HA-VTE in critically ill neonates. However, the level of risk associated with CVC is below the conventional threshold for primary anticoagulation thromboprophylaxis. Larger studies are needed to substantiate these findings and identify novel putative risk factors to further distinguish NICU patients at highest HA-VTE risk.

Fibrinolytic therapy of thrombosis in 27 newborns followed-up in neonatal intensive care unit

BACKGROUND AND AIM

We aimed to report newborns with thrombosis and needed fibrinolytic treatment.

PATIENTS AND METHODS

This was a retrospective study conducted on 27 newborns with thrombosis followed-up in a neonatal intensive care unit between December 2007 and December 2012. The patients were divided into two groups according to treatment protocol; Group 1 (n = 15): recombinant tissue-type plasminogen activator (r-tPA) and Group 2 (n = 12): streptokinase (STK). The groups were compared in terms of the efficacy and complications of the treatments.

RESULTS

In Group 1, flow restoration was complete in nine (60%) patients, partial in two (13.3%), and absent in four (26.7%). In Group 2, flow restoration was complete in seven (58.3%) patients, partial in three (25%), and absent in two (16.0%). The incidence of complete/partial recovery was similar in the groups. There was no difference between the two groups with regard to the duration of thrombus resolution. Fibrinolytic treatment was terminated in seven patients (46.7%) in Group 1, while in three patients (25%) in Group 2 due to the complications. The most common complications were minor or major bleedings. There was no statistically significant difference with regard to all bleedings complications between the two groups (P = .08), although the incidence of skin hemorrhages was higher in Group 1 (P = .007). There was no significant difference between the mortality rates.

CONCLUSION

Even though the use of STK is not further recommended because of its potential undesirable side effects in newborns, its efficacy and safety appears to be similar to those of r-tPA.

Risk-prediction tool for identifying hospitalized children with a predisposition for development of venous thromboembolism: Peds-Clot clinical Decision Rule

BACKGROUND

The prevalence of VTE is increasing in tertiary pediatric hospitals. Identification of high-risk populations using uniform criteria is required to develop evidence-based VTE prevention guidelines.

OBJECTIVE

To develop a VTE risk prediction rule, the Peds-Clot clinical Decision Rule (PCDR), to identify high-risk children who were at increased risk of developing VTE.

METHODS

This retrospective case-control study developed the PCDR using a derivation cohort (173 cases, 346 controls) and validated it on a separate validation cohort (100 cases, 100 controls). A uniform data collection strategy was applied to derive both the samples. Conditional logistic regression analyses were used to develop a risk-prediction model. Each significant predictor was assigned a score based on its beta coefficient and the PCDR was developed. ROC curves were derived to test the performance of the PCDR.

RESULTS

Characteristics of derivation and validation cohorts were comparable. Six risk factors (positive blood stream infection, central venous catheter, direct admission to ICU/NICU, hospitalization for ≥ 7 days, immobilization for > 72 h, and use of birth control pills) formed the final risk prediction model (risk score range, 0.5-9.5). A risk score of 3 or more identified high-risk children at a sensitivity of 70% and specificity of 80% and AUC of 0.852 (95% confidence interval, 0.814-0.890). The application of a risk score to the validation sample showed sensitivity 57% and specificity 88% and an AUC of 0.875 (95% confidence interval, 0.82-0.924).

CONCLUSION

Incorporation of the PCDR in routine clinical care can be an attractive strategy to identify high-risk hospitalized children with a predisposition for VTE. The clinical utility of the PCDR needs validation in prospective studies.

Myocardial infarction in a newborn heterozygous for the MTHFR C677T mutation

Neonatal myocardial infarction secondary to congenital heart disease, anomalous coronary artery anatomy, thromboembolism, coagulopathy, birth asphyxia, and unknown causes has been previously reported. We now report an infant who suffered a massive myocardial infarction during birth, requiring extensive resuscitation and aggressive management. A thrombus, the origin of which was not detected on autopsy, was found occluding the proximal left coronary artery several hours after birth. Genetic studies revealed a single copy variant of the MTHFR C677T mutation that we speculate may have predisposed the infant to coronary thrombosis.

Preterm infant with a catastrophic hemorrhagic-thromboembolic incident

Thrombotic disease of the newborn is uncommon but usually associated with serious morbidity and mortality. Although the operating mechanisms of coagulation and fibrinolysis are the same in all age groups, plasma concentrations of the two systems' components are significantly different in neonates compared to children and adults. This places neonates at greater risk for thrombosis that may rise considerably if a predisposing factor is present or a genetic or medical condition predisposing to thrombosis coexists. While marginal, the possibility of abnormal bleeding secondary to congenital prothrombotic disorders has been described. A significant association between thromboembolic/hemorrhagic disease in newborns and each of factor V(Leiden) and prothrombin G20210A mutations has been reported. Although not a frequent occurrence in adults and children, congenital 'multigenic' thrombophilia is well known. However, the combined heterozygote state of both mutations is perhaps underreported in preterm infants. We present a severely intrauterine growth-restricted preterm baby born to consanguineous parents. He had stroke as part of a generalized bleeding-thromboembolic incident caused by combined heterozygote mutation of factor V(Leiden) and prothrombin G20210A, each of which was then found in a heterozygote form in each of the 2 parents.

Neonatal portal vein thrombosis: diagnosis and management

Neonatal portal vein thrombosis (PVT) is an increasingly recognized event. Patients are generally asymptomatic in the neonatal period. The diagnosis is made with Doppler ultrasound. Umbilical catheterization, exchange transfusion and sepsis are risk factors for neonatal PVT. Thrombophilia is possibly a contributing risk factor. Although there are potential serious acute complications such as hepatic necrosis, the outcome is good in the majority of cases, followed up to 8 years of age. Thrombus resolution occurs in 30-70% in days to months. Liver lobe atrophy may occur following PVT, and does not appear to be associated with any impairment of liver function. Non-occlusive thrombosis is more likely to resolve than non-occlusive thrombosis. A subset of patients without resolution is at risk for developing portal hypertension over the next decade of life. There are no current defining features present during the neonatal period to enable identification of neonates at risk for portal hypertension. There is no evidence that anticoagulation therapy improves time to resolution or decreases the likelihood of portal hypertension. Anticoagulation therapy may be considered. A management algorithm is proposed.

Early intravenous immunoglobin (two-dose regimen) in the management of severe Rh hemolytic disease of newborn--a prospective randomized controlled trial

Phototherapy is the standard treatment in moderately severe hemolytic disease of newborn (HDN), whereas exchange transfusion (ET) is the second line in progressive cases. Intravenous immunoglobin (IVIG) has been suggested to decrease the need for ET. We aimed at assessing the efficacy of early two-dose regimens of IVIG to avoid unnecessary ET in severe Rh HDN. The study included 90 full-term neonates with Rh incompatibility unmodified by antenatal treatment and not eligible for early ET and which were randomly assigned into one of three groups: group (I), treated by conventional method; groups IIa and IIb received IVIG once at 12 h postnatal age if PT was indicated, in a dose of 0.5 and 1 g/kg, respectively. Analysis revealed 11 neonates (22%) in the conventional group and 2 (5%) in the intervention group who administered low-dose IVIG at 12 h, while none in group IIb required exchange transfusion (p = 0.03). Mean bilirubin levels were significantly lower during the first 96 h in the intervention group compared to the conventional group (p < 0.0001). Shorter duration of phototherapy (52.8 ± 12.39 h) and hospital stay (3.25 ± 0.71 days) in the IVIG group compared to conventional group (84 ± 12.12 h and 4.72 ± 0.78 days, p < 0.0001, respectively) were observed. We conclude that IVIG administration at 12 h was effective in the treatment of severe Rh HDN; the low-dose IVIG (0.5 g/kg) was as effective as high dose (1 g/kg) in reducing the duration of phototherapy and hospital stay, but less effective in avoiding exchange transfusion.

Umbilical vascular catheter associated portal vein thrombosis detected by ultrasound

OBJECTIVE

To determine catheter-associated thrombosis by color Doppler ultrasound and to detect duration of catheter placement as a risk factor for thrombosis.

METHODS

All newborn infants with umbilical vascular catheterization for more than 6 h duration were included in this study. Color Doppler ultrasound examination was performed within 24-48 h of catheter insertion, 48-72 h after its withdrawal and weekly until hospital discharge or clot resolution.

RESULTS

Portal vein thrombosis (PVT) was determined in five cases (3.04%) of 164 infants received umbilical vascular catheterization. The mean duration of catheter placement in patients with PVT was 3.4 ± 1.94 days, which was not significantly different from infants without thrombosis (3.5 ± 2.03). Thrombosis was completely recanalized and resolved after 3-6 weeks in three survived neonates. There was history of exchange transfusion for hyperbilirubinemia via umbilical vein in two neonates with PVT.

CONCLUSIONS

Catheter-associated portal venous thrombosis was uncommon in our study. The duration of catheter placement was not longer in patients with portal vein thrombosis than those without thrombosis.