[Chorioretinal atrophy in pediatric cerebral folate deficiency-a preventable disease?] / Chorioretinale Atrophie bei kindlichem zerebralem Folatmangel ­ eine vermeidbare Erkrankung?

Cerebral folate deficiency (CFD) results in neurological alterations and a massive degeneration of the choroid/retina if left untreated, which limit the visual field and visual acuity. This article reports the case of a female patient with CFD, who developed autistic personal characteristics prior to reaching school age and first started to speak at the age of 3 years. At the age of 6 years she was presented because of unclear reduced visual acuity in the right eye. At that time mild bilateral peripheral chorioretinal atrophy was present, which subsequently became more pronounced. Additionally, a centrally emphasized chorioretinal atrophy further developed. Visual acuity of both eyes progressively deteriorated until stagnating at 0.1 at the age of 14 years. The causal assignment of the findings of the patient was not possible for many years. Choroideremia was excluded by molecular genetic testing (CHM gene with no mutations) and gyrate atrophy was ruled out by a normal ornithine level. The existence of a mitochondrial disease was almost completely excluded by exome sequencing. After the onset of further nonocular symptoms, e.g. neuromuscular disorders, electroencephalograph (EEG) alterations and autistic disorder, intensified laboratory diagnostics were performed in the treating pediatric hospital. Finally, an extremely low level of the folic acid metabolite 5­methyltetrahydrofolate was detected in the cerebrospinal fluid (CSF) leading to the diagnosis of CFD. High-dose substitution treatment with folic acid was subsequently initiated. After excluding the presence of a pathogenic mutation of the FOLR1 gene for the cerebral folate receptor 1, a high titer blocking autoantibody against cerebral folate receptor 1 was detected as the cause.

[Adverse drug reactions in elderly people : First data from the Leipzig Research Center for Civilization Diseases (LIFE)]. / Unerwünschte Arzneimittelreaktionen beim älteren Menschen : Erste Daten aus dem Leipziger Forschungszentrum für Zivilisationserkrankungen (LIFE).

BACKGROUND: Few data exist on adverse drug reactions (ADR) in elderly people. In this group, pharmacotherapy represents a challenge with regard to comorbidities, drug interactions and compliance. OBJECTIVE: The aim of this article is to highlight the characteristics of ADR in elderly patients. METHODS: In addition to a literature review we present the first data from the Leipzig Research Center for Civilization Diseases (LIFE). Between 2011 and 2015 a total of 9537 subjects aged 40-79 years were randomly included in this population-based, age and sex standardized investigation in the inhabitants of Leipzig, Germany and special emphasis was placed on allergies including questions with regard to ADR. RESULTS: Of the 9537 subjects, data on allergies were available from 8979 subjects. Female gender, comorbidities and the use of multiple drugs were significantly associated with an increased risk of ADR. Women also reported ADR significantly more frequently than men. Of the subjects 22% reported suffering from some form of ADR as a result of medications, while in 2.3% this reaction had occurred within the previous 12 months. Less than 15% of LIFE patients with ADR were in possession of a document giving details of the ADR. DISCUSSION: The occurrence of ADR significantly contributes to morbidity in elderly patients. For prevention of ADR knowledge of patient-related factors, underlying diseases, drug characteristics and drug interactions are necessary.

Deficiency or inhibition of lysophosphatidic acid receptor 1 protects against hyperoxia-induced lung injury in neonatal rats.

AIM: Blocking of lysophosphatidic acid (LPA) receptor (LPAR) 1 may be a novel therapeutic option for bronchopulmonary dysplasia (BPD) by preventing the LPAR1-mediated adverse effects of its ligand (LPA), consisting of lung inflammation, pulmonary arterial hypertension (PAH) and fibrosis. METHODS: In Wistar rats with experimental BPD, induced by continuous exposure to 100% oxygen for 10 days, we determined the beneficial effects of LPAR1 deficiency in neonatal rats with a missense mutation in cytoplasmic helix 8 of LPAR1 and of LPAR1 and -3 blocking with Ki16425. Parameters investigated included survival, lung and heart histopathology, fibrin and collagen deposition, vascular leakage and differential mRNA expression in the lungs of key genes involved in LPA signalling and BPD pathogenesis. RESULTS: LPAR1-mutant rats were protected against experimental BPD and mortality with reduced alveolar septal thickness, lung inflammation (reduced influx of macrophages and neutrophils, and CINC1 expression) and collagen III deposition. However, LPAR1-mutant rats were not protected against alveolar enlargement, increased medial wall thickness of small arterioles, fibrin deposition and vascular alveolar leakage. Treatment of experimental BPD with Ki16425 confirmed the data observed in LPAR1-mutant rats, but did not reduce the pulmonary influx of neutrophils, CINC1 expression and mortality in rats with experimental BPD. In addition, Ki16425 treatment protected against PAH and right ventricular hypertrophy. CONCLUSION: LPAR1 deficiency attenuates pulmonary injury by reducing pulmonary inflammation and fibrosis, thereby reducing mortality, but does not affect alveolar and vascular development and, unlike Ki16425 treatment, does not prevent PAH in neonatal rats with experimental BPD.

Posterior fossa abnormalities in high-risk term infants: comparison of ultrasound and MRI.

OBJECTIVES: We aimed to assess the characteristics of posterior fossa (PF) abnormalities in a cohort of high-risk term neonates, as well as the diagnostic performance of cranial ultrasound (CUS) with additional mastoid fontanelle (MF) views for the detection of these abnormalities, with magnetic resonance imaging (MRI) being the reference standard. METHODS: In this retrospective study, 113 term neonates with CUS and subsequent MRI were included. Sensitivity, specificity, and predictive values of routine CUS and CUS with MF views were calculated. RESULTS: Posterior fossa abnormalities were diagnosed on CUS in 46 of 113 infants. MRI confirmed these findings in 43 and showed additional abnormalities in 32 infants. The sensitivity and specificity of anterior fontanelle views for major PF abnormalities as seen on MRI were 16% and 99%. Adding MF views increased the sensitivity of US to 82%. The sensitivity and specificity of MF views for the detection of any (major or minor) PF abnormality were 57% and 95%. Especially acute hypoxic-ischemic injury and small subdural and punctate cerebellar haemorrhage remained undetected by CUS. CONCLUSIONS: PF abnormalities are frequent in high-risk term infants. MF-CUS enables early diagnosis of major PF abnormalities. We therefore advocate to perform MF-CUS in high-risk term neonates. KEY POINTS: • Posterior fossa abnormalities are a frequent finding in high-risk term infants. • Adding mastoid fontanelle views improves ultrasound detection of clinically relevant abnormalities. • Hypoxic-ischemic injury and small posterior fossa haemorrhages are better detected with MRI. • Cranial ultrasound examination should include mastoid fontanelle views in high-risk term neonates.

Profiling the preterm or VLBW born adolescent; implications of the Dutch POPS cohort follow-up studies.

In 1983, data of a unique nationwide cohort of 1338 very preterm (<32 weeks of gestation) or VLBW (birth weight<1500g) infants in the Netherlands was collected and followed at several ages until they reached the age of 19 years. At 19 years of age a more extensive follow-up study was done, including questionnaires, tests on a computer and a full physical exam. These studies provide insight into how Dutch adolescents at 19 years of age, who were born very preterm or with a very low birth weight (VLBW), reach adulthood. At 19 years, 705 POPS participants participated (74% of 959 still alive). Outcome measures at 19 years included: physical outcomes (e.g. blood pressure), cognition, behavior, quality of life, and impact of handicaps. The POPS participants showed more impairments on most outcome measures at various ages, compared to norm data. Major handicaps remained stable as the children grew older, but minor handicaps and disabilities increased. At 19 years of age, only half (47.1%) of the survivors had no disabilities and no minor or major handicaps. Especially those born small for gestational age (SGA) seem most vulnerable. These long-term results help to support preterm and SGA born children and adolescents in reaching independent adulthood, and stress the need for long term follow-up studies and to promote prevention of disabilities and of preterm birth itself.

Reproductive outcomes of women and men born very preterm and/or with a very low birth weight in 1983: a longitudinal cohort study in the Netherlands.

UNLABELLED: The aims of this study were to analyze reproductive outcomes of women and men born very preterm (gestational age <32 weeks) or with a very low birth weight (<1500 g) in 1983 in the Netherlands and to compare their reproductive outcomes with the total population at a similar age of 28 years. Young adults who were born after a pregnancy complicated by very preterm (VP) delivery or with a very low birth weight (VLBW) in the Netherlands in 1983 (Project on Preterm and Small for Gestational Age Infants (POPS) cohort) were invited to complete an online questionnaire at the age of 28. In total, 293 POPS-28 participants (31.6%) completed the questionnaire including 185 female and 108 male participants. Female and male participants who were born VP or with a VLBW had significant reduced reproductive rates compared to the total Dutch population at 28 years of age (female 23.2 vs 31.9% and male 7.4 vs 22.2%). Pregnancies of the female participants were in 14% complicated by preterm delivery in at least one pregnancy. CONCLUSION: This study indicates that women and men born VP or with a VLBW have reduced reproductive rates at the age of 28 compared to the total Dutch population at a similar age.

Auditing documentation on delivery room management using video and physiological recordings.

OBJECTIVE: Neonatal resuscitation is often retrospectively documented, which can lead to inaccuracy and incomplete recording of delivery room management. In this study, we assessed the accuracy and completeness of neonatal resuscitation documentation in our neonatal intensive care unit. METHODS: Recordings of physiological parameters and video data were performed in the delivery room and used to deduct the clinical condition of the infant, the interventions done and their effect on the infant's condition. The data from the recordings were compared with the documentation on neonatal stabilisation in the medical records (paper or digital). RESULTS: Recordings of 54 infants were compared with the documentation in their medical records. In 93% of the medical records delivery room management was documented. The clinical condition of the infant at birth was documented in 76% and 1 min Apgar scores in 98%. Respiratory support was correctly documented in 83%, heart rate in 37% and oxygen saturation in 13%. In 57% use of supplemental oxygen and its indication were correctly reported. Seven infants were intubated and this was correctly documented in 57%. Apgar scores were compared between the recordings and the medical records. At 1 min, 5 min and 10 min after birth the Apgar score, given by the researcher using the recordings, was similar to the scores in the medical records in 33%, 44% and 53%, respectively. CONCLUSIONS: Accurate and complete documentation of neonatal resuscitation continues to be a challenge. Recordings of physiological parameters and video imaging can improve documentation by providing detailed information.

Early-onset thrombocytopenia in near-term and term infants with perinatal asphyxia.

BACKGROUND: Neonates after perinatal asphyxia are at increased risk of thrombocytopenia. The correlation between perinatal asphyxia and the risk and severity of early-onset thrombocytopenia is not well known. OBJECTIVE: To estimate the incidence, severity and risk factors for early-onset thrombocytopenia in neonates after perinatal asphyxia. METHODS: We included all newborns (gestational age ≥ 36 weeks) admitted to our neonatal nursery due to perinatal asphyxia in this retrospective study. We collected platelet counts that were obtained within the first 48 h of life to estimate the incidence and severity of early-onset thrombocytopenia. RESULTS: A total number of 171 neonates with perinatal asphyxia were included in the study. The incidence of early-onset thrombocytopenia (platelet count < 150 × 109/l) was 51% (87/171). Several factors were associated with increased risk of early-onset thrombocytopenia, including prolonged prothrombin time (PT) [odds ratio (OR) 1·18, 95% confidence interval (CI) 1·08­1·30, P < 0·01], prolonged activated partial thromboplastin time (APTT) (OR 1·07, 95% CI 1·03­1·11, P < 0·01), low Apgar score at 10 min (OR 1·25, 95% CI 1·08­1·45, P < 0·01) and high serum lactate (OR 1·12, 95% CI 1·06­1·19, P < 0·01). After multiple logistic regression analysis, we found an independent association between early-onset thrombocytopenia and prolonged PT (OR 1·15, 95% CI 1·00­1·33, P = 0·045) and higher lactate level (OR 1·15, 95% CI 1·03­1·28, P = 0·01). CONCLUSIONS: Early-onset thrombocytopenia occurs frequently in neonates after perinatal asphyxia and is independently associated with PT and lactate level.

Doxapram use for apnoea of prematurity in neonatal intensive care.

Apnoea of prematurity is treated with noninvasive respiratory therapy and methylxanthines. For therapy unresponsive apnoea doxapram is often prescibed in preterm neonates. The duration, dosage and route of administration of doxapram together with its efficacy was evaluated in two Dutch neonatal intensive care. Outcome concerning short-term safety and neonatal morbidity were evaluated. During 5 years, 122 of 1,501 admitted newborns <32 weeks of gestational age received doxapram. 64.8% of patients did not need intubation after doxapram. 25% of treated neonates were <27 weeks of gestation. A positive response to doxapram therapy on apnoea was associated with longer duration of doxapram usage (P < 0.001), lower mean doses (P < 0.003), and less days of intensive care (median 33 versus 42 days; P < 0.002). No patients died during doxapram therapy. Incidence of necrotizing enterocolitis, intraventricular hemorrhage, periventricular leukomalacia, retinopathy of prematurity, persistent ductus arteriosus, or worsening of pulmonary condition did not increase during doxapram therapy. Doxapram is frequently used for apnoea of prematurity, despite a lack of data on short-term efficacy and long-term safety. Until efficacy and safety are confirmed in prospective trials, doxapram should be used with caution.

Outcome and management in neonatal thrombocytopenia due to maternal idiopathic thrombocytopenic purpura.

BACKGROUND AND OBJECTIVES: Pregnant women with Idiopathic thrombocytopenic purpura (ITP) can deliver neonates with severe thrombocytopenia. Clear evidence declaring the pathophysiological cause of this neonatal thrombocytopenia is lacking, as antiplatelet antibodies are not always detectable in maternal serum. Severe neonatal thrombocytopenia below 50 × 10(9) /l is reported in 8-13% of the neonates from mothers with ITP and intracranial haemorrhage (ICH) in 0-2·9%. Evidence about the optimal postnatal treatment is scarce. Our objective was to evaluate the outcome and management in neonates with passive ITP. MATERIALS AND METHODS: All neonates from mothers with ITP born between 1980 and 2011 were included. Platelet counts during the first 10 days, presence of ICH and postnatal treatment were recorded. Maternal characteristics were analysed as possible risk factors for severe neonatal thrombocytopenia. RESULTS: Sixty-seven neonates were included. Severe thrombocytopenia (<50 × 10(9) /l) occurred in 20/67 (29·9%) neonates. In three neonates, platelet count rose spontaneously, 18 neonates were treated (one with persistent moderate thrombocytopenia) with the following: platelet transfusions (3), prednisone (2), intravenous immunoglobulin (IVIG) (1), platelet transfusions and IVIG (11), platelet transfusion and prednisone (1). Recurrence of low platelet counts after transfusions was commonly seen. Risk factors for severe neonatal thrombocytopenia were a previous sibling with severe thrombocytopenia and low maternal platelet nadir during pregnancy. CONCLUSION: In this cohort, severe neonatal thrombocytopenia occurs more frequently than previously reported. To maintain a platelet count above 50 × 10(9) /l, often multiple transfusions and IVIG are required. Multiple transfusions may be avoided by starting IVIG, when platelet count falls below 50 × 10(9) /l after the first platelet transfusion.

Iron status in infants with alloimmune haemolytic disease in the first three months of life.

BACKGROUND AND OBJECTIVES: Ferritin levels are often highly elevated at birth in neonates with alloimmune haemolytic disease of the fetus and newborn (HDFN). Data on ferritin levels in these infants in the first 3 months of life are lacking. Objective of this study was to examine the course of iron status and incidence of iron deficiency and overload in neonates with alloimmune HDFN up to 3 months of age. Secondary objective was to analyse bilirubin levels, liver enzymes and red-blood-cell indices in the same time period and the association with intrauterine transfusion (IUT). MATERIALS AND METHODS: Observational study of neonates with alloimmune HDFN admitted to our centre between November 2010 and March 2012. Data on iron status, bilirubin levels, liver enzymes and red-blood-cell indices up to 3 months of age were routinely collected and compared between neonates treated with and without IUT. RESULTS: Thirty-five infants with alloimmune HDFN were included. Iron overload occurred in 70% of neonates at birth and in 50% and 18% at the age of 1 and 3 months, respectively. No cases of iron deficiency at birth and only one case of iron deficiency at 3 months of age were found. No infants received iron therapy. Infants who received IUT had a significantly lower haemoglobin level and reticulocyte count and higher ferritin level at birth. CONCLUSION: The vast majority of neonates with alloimmune HDFN have iron overload at birth. Incidence of iron overload gradually decreases within the first 3 months without iron supplementation.

Prevalence, size, number and localization of vascular anastomoses in monochorionic placentas.

INTRODUCTION: Most monochorionic (MC) twin pregnancies have an uncomplicated course, but some develop severe complications including selective intrauterine growth restriction (sIUGR), twintwin transfusion syndrome (TTTS) and twin anemia-polycythemia sequence (TAPS). The underlying pathogenesis of these various complications is associated with the ubiquitous presence of vascular anastomoses in MC placentas. METHODS: The aim of this study was to estimate the prevalence, number, size and localization of the anastomoses in sIUGR, TTTS and TAPS placentas compared to normal MC placentas using color dye injection. We excluded MC twin pregnancies treated with fetoscopic laser surgery or selective feticide. RESULTS: A total of 235 placentas fulfilled the inclusion criteria: 126 normal MC, 47 TTTS, 46 sIUGR and 16 spontaneous TAPS. Median number of anastomoses in normal MC, sIUGR, TTTS and TAPS placentas was 8 (IQR: 4-12), 8 (IQR: 5-14), 7 (IQR: 5-11) and 4 (IQR: 3-5), respectively. The prevalence of arterio-arterial (AA) anastomoses in normal MC, sIUGR, TTTS and TAPS placentas was 96%, 98%, 47% and 19%, respectively. We found AV anastomoses to be evenly distributed along the vascular equator in all MC placentas except in TAPS cases, where anastomoses were mostly localized near the margin. We also found that, in sIUGR and TTTS placentas, AA anastomoses tended to be at the center of the placenta. CONCLUSION: The present study shows that the prevalence, size, number and localization of the various types of anastomoses differ between normal MC, sIUGR, TTTS and TAPS placentas.

Hypoalbuminemia in donors with twin anemia-polycythemia sequence: a matched case-control study.

OBJECTIVE: To determine the differences in albumin levels between donors and recipients with twin anemia-polycythemia sequence (TAPS). METHODS: We included all consecutive monochorionic twins with TAPS with double survivors. Each twin pair was matched for gestational age at birth with 2 control monochorionic twin pairs unaffected by TAPS or twin-twin transfusion syndrome. We measured levels of albumin, total protein, and hemoglobin on the first day of life in donors and recipients (TAPS group) and the control group. RESULTS: A total of 25 TAPS twin pairs and 50 control twin pairs were included in the study. The median gestational age at birth was 32 weeks in both groups. In the TAPS group, median levels (IQR) of albumin in donor twins were significantly lower than in recipient twins, i.e. 28.0 g/l (24.0-32.0) versus 32.0 g/l (30.0-34.5) (p = 0.008). Median levels (IQR) of total protein in donor twins were also lower than in recipients, i.e. 44.0 g/l (36.5-49.0) versus 49.0 g/l (46.5-51.0), respectively (p = 0.004). The median (IQR) intertwin albumin difference was significantly higher in the TAPS group than in the control group, i.e. 4.0 g/l (2.5-10.5) versus 2.0 g/l (1.0-4.0) (p = 0.003). The rate of hypoalbuminemia (<20 g/l) and hypoproteinemia (<40 g/l) in donor twins with TAPS was 20% (5/25) and 32% (8/25). CONCLUSIONS: In addition to lower hemoglobin levels, donor twins with TAPS also have significantly lower albumin and total protein levels compared to recipient twins.

Placental characteristics in monochorionic twins with spontaneous versus post-laser twin anemia-polycythemia sequence.

INTRODUCTION: Twin anemia-polycythemia sequence (TAPS) may occur in monochorionic twins either spontaneously or after laser surgery for twin-twin transfusion syndrome. Our aim was to analyze the placental angioarchitecture in spontaneous versus post-laser TAPS. METHODS: We included all monochorionic twin placentas with spontaneous or post-laser TAPS injected at our center between 2002 and 2012. Placental angioarchitecture was evaluated using colored dye injection. RESULTS: A total of 600 monochorionic placentas were injected during the study period of which 43 (7.2%) with TAPS (spontaneous TAPS, n = 16; post-laser TAPS, n = 27). Almost all anastomoses (96%; 119/124) were very small (diameter <1 mm) and the majority was localized near the placental margin. The median number of anastomoses per placenta was 4 (interquartile range (IQR): 3-5) in the spontaneous TAPS group and 2 (IQR: 1-3) in the post-laser TAPS group (p = 0.003). Arterio-arterial (AA) anastomoses were detected in 14.0% (6/43) of TAPS placentas and were all minuscule (diameter <1 mm). The rate of AA anastomoses in the spontaneous TAPS group and post-laser TAPS group was 18.8% (3/16) and 11.1% (3/27), respectively (p = 0.184). DISCUSSION: Spontaneous TAPS placentas have a significantly higher total number of anastomoses compared to post-laser TAPS placentas. Most anastomoses were localized near the margins of the placenta. Minuscule AA anastomoses were detected sporadically in both groups and the rate of AA anastomoses is slightly higher in the spontaneous TAPS group than in the post-laser group. CONCLUSION: Spontaneous TAPS placentas have a different placental angioarchitecture than post-laser TAPS placentas in terms of number and type of vascular anastomoses.

Acute hemorrhage in monochorionic twins with ruptured velamentous vessels: anemic twin resuscitated by its co-twin through placental vascular anastomoses?

Monochorionic (MC) twin pregnancies are at increased risk of several complications including acute or chronic twin-twin transfusion syndrome (TTTS) and twin anemia-polycythemia sequence (TAPS). Both TTTS and TAPS result from inter-twin fetofetal transfusion through the placental vascular anastomoses. In addition, MC twin pregnancies are at increased risk of having a velamentous cord insertion, which has been linked with poor perinatal outcome due to risk of rupture of the velamentous vessels. In sporadic cases, these vascular connections may have a positive effect instead of a deleterious effect. We present a case of acute fetal distress in a MC twin pregnancy caused by acute hemorrhage following rupture of velamentous vessels. An emergency cesarean section delivery was performed at 29+2 weeks' gestation. One infant was severely anemic at birth and required immediate treatment with volume expansion and blood transfusion. Acute fetal blood loss through the ruptured vessels led to an acute fetofetal transfusion from the co-twin through the placental vascular anastomoses. Delayed intervention could have resulted in severe hypovolemic shock and acute anemia in both fetuses. Instead, in the current case, placental vascular anastomoses had a transient protective role and allowed transfusion of blood from one co-twin into the circulation of the anemic twin.

Hypoalbuminemia in donors with twin-twin transfusion syndrome.

OBJECTIVE: To estimate the differences in albumin levels between donors and recipients with twin-twin transfusion syndrome (TTTS). METHODS: We performed a matched case-control study including twin pairs with TTTS treated conservatively (conservative group) or with fetoscopic laser surgery (laser group) and analyzed the albumin levels at birth in donor and recipient twins. RESULTS: We included 18 twin pairs in the conservative group and 36 control twin pairs (laser group), matched for gestational age at birth. Median albumin levels in donor twins in the conservative group were significantly lower than in recipient twins, 25.0 versus 33.0 g/l, respectively (p = 0.001). In the laser group, albumin levels in donors and recipients were similar, 32.0 versus 32.0 g/l, respectively (p = 0.633). Hypoalbuminemia (albumin level <20 g/l) occurred in 22% (4/18) of donor twins in the conservative group. CONCLUSIONS: Hypoalbuminemia occurs frequently in donor twins with TTTS treated conservatively. In TTTS treated with laser, donor twins have similar and normal albumin levels compared to recipients, confirming a successfully performed fetoscopic laser procedure.

Arterio-arterial vascular anastomoses in monochorionic placentas with and without twin-twin transfusion syndrome.

We performed a matched case-control study to analyze the placental angioarchitecture, in particular the diameter of arterio-arterial (AA) anastomoses in monochorionic placentas from pregnancies with twin-twin transfusion syndrome (TTTS) compared to a control group of uncomplicated monochorionic placentas. Placental angioarchitecture was analyzed using colored dye injection. AA anastomoses were detected in 37% (14/38) of TTTS placentas versus 91% (209/228) in control placentas (p < 0.001). The median diameter of AA anastomoses in the group with and without TTTS was 1.9 mm and 2 mm, respectively (p = 0.711). In conclusion, our findings show that AA anastomosis occur less frequently in TTTS placentas, supporting the concept of the protective role of AA anastomoses in TTTS. However, the size of the AA anastomosis, when present, does not appear to influence the pathophysiology of the disease.

Arterio-arterial vascular anastomoses in monochorionic twin placentas with and without twin anemia-polycythemia sequence.

We performed a matched case-control study to analyze the placental angioarchitecture, in particular the diameter of arterio-arterial (AA) anastomoses in monochorionic placentas from pregnancies with spontaneous twin anemia-polycythemia sequence (TAPS) compared to a control group of uncomplicated monochorionic placentas. Placental angioarchitecture was analyzed using colored dye injection. AA anastomoses were detected in 20% (3/15) of spontaneous TAPS placentas. The median diameter of AA anastomoses in the group with and without TAPS was 0.4 mm and 2.2 mm, respectively (p = 0.01). In conclusion, AA anastomoses are rarely detected in TAPS placentas. When present, the AA anastomosis is very small, preventing equilibration of hemoglobin levels between both twins.