Evaluation of Vascular Health of E-Beta Thalassemia Patients: Effect of Iron Overload.

Hb E-ß thalassemia is the most common form of hemoglobinopathy in Southeast Asia and eastern India. Iron overload resulting from blood transfusion and increased intestinal iron absorption promotes the formation of reactive oxygen species (ROS), leading to oxidative stress, organ dysfunction, and tissue damage. Of these, cardiovascular complications are the leading cause of mortality. Impaired endothelial function is a biomarker of vascular health in patients with cardiovascular risks. Therefore, assessment of endothelial function is a useful prognostic tool. In the present study, 60 E- ß thalassemia patients and 60 healthy, age, sex matched control subjects were taken. The mean hemoglobin and ferritin of thalassemic patients were 7.43gm/dl and 1032 mcg/dl respectively. The vascular health was compared by measuring flow-mediated vasodialation (FMD), arterial elastic parameters, and carotid intima-medial thickness (CIMT). There was lower FMD (7.49%) and higher CIMT (0.46mm) in thalassemic group than control (10.52 % and 0.36mm respectively) (p value< 0.05). Also arterial stiffness is elevated and arterial distensibility is lower in thalassemic patients than control. Among the thalassemic patients FMD or CIMT did not correlate with serum ferritin value. So, the E- ß thalassemia patients had poor vascular health and are at a higher risk of developing atherosclerosis and cardio-vascular complication than normal population. The vascular dysfunction does not correlate with serum ferritin value, so regular monitoring with Doppler study is required for early diagnosis of subclinical atherosclerosis in this group of patients. However the effects of chelation therapy, Hydroxyurea, or other targeted therapies needs to be validated by further study.

Large scale validation of a new non-invasive and non-contact bilirubinometer in neonates with risk factors.

The study was aimed to evaluate the performance of a newly developed non-invasive and non-contact bilirubin measurement device (AJO-Neo) as an alternative to the conventional invasive biochemical method of total serum bilirubin (TSB) estimation in preterm and term neonates suffering from hyperbilirubinemia associated with risk factors, and/or undergoing phototherapy. The safety and efficacy of the device were assessed in 1968 neonates with gestational ages ranging from 28 to 41 weeks and suffering from incidences of hyperbilirubinemia. Linear regression analysis showed a good correlation between AJO-Neo and the conventional method of TSB (Pearson's coefficient, r = 0.79). The small bias (0.27 mg/dL) and limits of agreements (- 3.44 to 3.99 mg/dL) were within the range of clinical acceptance. The device was also precise in the measurement of bilirubin levels in all subgroups of the study. The receiver operator curve (ROC), that takes account of both sensitivity and specificity of a device showed high efficacy of the device (area under the curve, AUC = 0.83) in the detection of bilirubin. While monitoring the bilirubin level during phototherapy, the device indicated promising results showing good agreement with TSB. Specificities and sensitivities of the device indicated a much higher accuracy in neonates with associated risk factors for hyperbilirubinemia. Hence, the newly developed device (AJO-Neo) is reliable in measuring bilirubin level in preterm, and term neonates irrespective of gestational or postnatal age, sex, risk factors, feeding behavior or skin color.

A Novel Whole Spectrum-Based Non-Invasive Screening Device for Neonatal Hyperbilirubinemia.

OBJECTIVE: Careful screening of bilirubin level in newborns is mandatory as per American Academy of Pediatrics (2004), to reduce incidents of kernicterus and acute bilirubin encephalopathy. Although, invasive capillary collection of blood and subsequent biochemical test is considered a gold standard for jaundice detection in neonates, transcutaneous bilirubin measurement using various non-invasive instruments is also used sporadically across the globe. The major aim of this study was to develop a non-invasive spectrometry-based technique for measurement of neonatal bilirubin level as an alternative of total serum bilirubin (TSB) test without limitations of other available bilirubinometers. METHODS: The instrument comprises of a light source and a spectroscopic detector. A light beam from source incident on the neonatal nail plate through optical fibers. The retro reflected light is acquired using the detector. An indigenously developed software is used to acquire and analyze the optical signal and to calculate the bilirubin value. The instrument was calibrated and validated in reference to TSB on 1033 subjects. MAJOR RESULTS: The result (r = 0.95 and P < 0.001) indicates a strong correlation between the bilirubin value obtained from our method and TSB. Time variant analysis of the subjects undergoing phototherapy provided a good correlation (r = 0.98). The repeatability test result shows the mean coefficient of variation is less than 5.0%. CONCLUSIONS: The indigenously developed non-invasive technique successfully detects the bilirubin level in newborns under various physiological conditions with high accuracy and precision.