Elevated Activin A urine levels are predictors of intraventricular haemorrhage in preterm newborns

Activin-A urine levels correlate with radiological patterns in preterm infants complicated by intraventricular hemorrhage

BACKGROUND

To validate the role of Activin A in the early diagnosis and prognosis of preterm newborns at risk for intraventricular hemorrhage and neurological sequelae by means of cerebral ultrasound and magnetic resonance imaging (MRI), currently considered standard of care procedures.

METHODS

We conducted an observational case-control study in 46 preterm newborns, 23 with intraventricular hemorrhage (IVH group) and 23 controls matched for gestational age. Standard clinical, laboratory, cerebral ultrasound monitoring procedures and Activin A urine measurement were performed at four time-points (first void, 24, 48, 96 h) after birth. Cerebral MRI was performed at 40-42 weeks of corrected gestational age.

RESULTS

Elevated (P < 0.001, for all) Activin A levels were observed in the IVH group at all monitoring time-point. Activin A correlated (P < 0.05, for all) with intraventricular hemorrhage grade on cerebral ultrasound. At the cut-off of 0.08 pg/mL Activin A at 48-h achieved the best sensitivity, specificity, positive/negative predictive values as early predictor of an abnormal MRI pattern (area under the curve: 0.93).

CONCLUSIONS

The present data showing a correlation among Activin A, cerebral ultrasound and MRI provide further support to Activin A inclusion in clinical daily management of cases at risk for intraventricular hemorrhage and adverse neurological outcome.

Navigating the Complexities of Intraventricular Hemorrhage in Preterm Infants: An Updated Review

Intraventricular hemorrhage (IVH) is a type of bleeding that occurs in the ventricular cavity of the brain. In this comprehensive study, we provide a summary of the pathogenesis, diagnosis, and treatment of intraventricular hemorrhage in premature infants. Preterm babies are at high risk of developing IVH because their germinal matrix is not fully developed, making their blood vessels more prone to rupture. However, that is not necessarily the case in all preterm babies as the inherent structure of the germinal matrix makes it more susceptible to hemorrhage. Incidences of IVH are discussed based on recent data which states that around 12,000 premature infants in the United States experience IVH each year. Although grades I and II make up the majority of IVH cases and are frequently asymptomatic, IVH remains a significant issue for premature infants in neonatal intensive care facilities worldwide. Grades I and II have been linked to mutations in the type IV procollagen gene, COL4A1, as well as prothrombin G20210A and factor V Leiden mutations. Intraventricular hemorrhage can be detected using brain imaging in the first seven to 14 days following delivery. This review also shines a light on reliable methods for identifying IVH in premature newborns like cranial ultrasound and magnetic resonance imaging along with the treatment of IVH which is primarily supportive and involves the management of intracranial pressure, the correction of coagulation abnormalities, and the prevention of seizures.

Serum Activin A as Brain Injury Biomarker in the First Three Days of Life. A Prospective Case-Control Longitudinal Study in Human Premature Neonates

Disruption of normal intrauterine brain development is a significant consequence of premature birth and may lead to serious complications, such as neonatal brain injury (NBI). This prospective case-control longitudinal study aimed at determining the levels and prognostic value of serum activin A during the first three days of life in human premature neonates which later developed NBI. It was conducted in a single tertiary hospital and eligible participants were live-born premature (<34 weeks) neonates. Each case (n = 29) developed NBI in the form of an intraventricular haemorrhage, or periventricular leukomalacia, and was matched according to birth weight and gestational age to one neonate with normal head ultrasound scans. Serum activin A levels in both groups showed a stable concentration during the first three days of life as no difference was observed within the two groups from the first to the third day. Neonates diagnosed with NBI had significantly higher activin A levels during the first two days of life compared to control neonates and its levels correlated to the severity of NBI during the second and third day of life. Although serum activin A on the second day was the best predictor for neonates at risk to develop NBI, the overall predictive value was marginally fair (area under the ROC-curve 69.2%). Activin A, in combination with other biomarkers, may provide the first clinically useful panel for the early detection of premature neonates at high risk of NBI.

Early predictors of perinatal brain damage: the role of neurobiomarkers

The early detection of perinatal brain damage in preterm and term newborns (i.e. intraventricular hemorrhage, periventricular leukomalacia and perinatal asphyxia) still constitute an unsolved issue. To date, despite technological improvement in standard perinatal monitoring procedures, decreasing the incidence of perinatal mortality, the perinatal morbidity pattern has a flat trend. Against this background, the measurement of brain constituents could be particularly useful in the early detection of cases at risk for short-/long-term brain injury. On this scenario, the main European and US international health-care institutions promoted perinatal clinical and experimental neuroprotection research projects aimed at validating and including a panel of biomarkers in the clinical guidelines. Although this is a promising attempt, there are several limitations that do not allow biomarkers to be included in standard monitoring procedures. The main limitations are: (i) the heterogeneity of neurological complications in the perinatal period, (ii) the small cohort sizes, (iii) the lack of multicenter investigations, (iv) the different techniques for neurobiomarkers assessment, (iv) the lack of consensus for the validation of assays in biological fluids such as urine and saliva, and (v), the lack of reference curves according to measurement technique and biological fluid. In the present review we offer an up-to-date overview of the most promising developments in the use of biomarkers in the perinatal period such as calcium binding proteins (S100B protein), vasoactive agents (adrenomedullin), brain biomarkers (activin A, neuron specific enolase, glial fibrillary acidic protein, ubiquitin carboxyl-terminal hydrolase-L1) and oxidative stress markers.

Identification of Urinary Activin A as a Novel Biomarker Reflecting the Severity of Acute Kidney Injury

Acute kidney injury (AKI) is a common but complex condition that is associated with increased morbidity and mortality. In the present study, we examined whether urinary activin A, a member of the TGF-beta superfamily, is present in mice with ischemia-reperfusion injury and in humans with AKI, as well as its potential as a biomarker for AKI. Expression of activin A was markedly increased in ischemic mouse kidneys. In situ hybridization demonstrated that activin mRNA was expressed in tubular cells of ischemic kidneys but not of normal kidneys. Immunoreactive activin A, which was absent in normal kidneys, was detected in the cytoplasm of proximal tubular cells in ischemic kidneys. Activin A was undetectable in the urine of normal mice. In contrast, activin A was significantly increased in the urine of ischemic mice at 3 h after reperfusion. Urinary activin A levels increased according to the period of ischemia. In humans, urinary activin A was almost undetectable in healthy volunteers and in patients with pre-renal AKI, but was significantly increased in patients with renal AKI. There was no significant correlation between urinary activin A and serum activin A. Collectively, urinary activin A might be a useful biomarker reflecting the severity of AKI.

Perinatal biomarkers in prematurity: early identification of neurologic injury

Over the past few decades, biomarkers have become increasingly utilized as non-invasive tools in the early diagnosis and management of various clinical conditions. In perinatal medicine, the improved survival of extremely premature infants who are at high risk for adverse neurologic outcomes has increased the demand for the discovery of biomarkers in detecting and predicting the prognosis of infants with neonatal brain injury. By enabling the clinician to recognize potential brain damage early, biomarkers could allow clinicians to intervene at the early stages of disease, and to monitor the efficacy of those interventions. This review will first examine the potential perinatal biomarkers for neurologic complications of prematurity, specifically, intraventricular hemorrhage (IVH), periventricular leukomalacia (PVL) and posthemorrhagic hydrocephalus (PHH). It will also evaluate knowledge gained from animal models regarding the pathogenesis of perinatal brain injury in prematurity.