RELATIONSHIP BETWEEN INSULIN-LIKE GROWTH FACTOR TYPE 1 AND INTRAUTERINE GROWTH.

Insulin-like growth factor 1 (IGF-1) is a regulator of intrauterine growth, and circulating concentrations are reduced in intrauterine growth-restricted fetuses. The aim of our study was to investigate the relationship between IGF-1 levels in newborns and intrauterine growth, expressed as birth weight (BW). The research was designed as a cross-sectional study. The study included 71 premature newborns, gestational age (GA) ≤33 weeks. Quantitative determination of IGF-1 was performed in the 33rd post-menstrual week (pmw) to make the measurements more comparable. We used an enzyme-bound immunosorbent test for quantitative determination of IGF-1. Our results showed the mean IGF-1 level in premature newborns in 33rd pmw to be 23.1±4.56 (range 15.44-39.75) µg/L. There was no difference in IGF-1 values between male (23.1±4.98 µg/L) and female (23.1±4.87 µg/L) newborns. There was no significant difference in the average IGF-1 levels between male and female newborns with BW <50th and BW >50th percentile for GA either (p>0.50). Only BW <33rd percentile newborns had a statistically significantly lower IGF-1 level compared to newborns with greater BW. Based on our results, it is concluded that serum IGF-1 level reflects intrauterine growth only in BW <33rd percentile newborns. This fact could be used for further therapeutic purposes.

PRO-OXIDANTS AND ANTIOXIDANTS IN RETINOPATHY OF PREMATURITY.

- Premature infants are susceptible to oxidative stress that causes neonatal disease such as retinopathy of prematurity (ROP). Oxidative stress is an imbalance between the production of pro-oxidants and the ability of the body to detoxify their harmful effects by antioxidants. The proliferative phase 2 ROP occurs at around 33rd postmenstrual week (pmw). The purpose of our study was to evaluate the pro-oxidant/antioxidant status in preterm infants at 33rd pmw. The study included 59 premature infants. ROP was classified according to the International Classification of Retinopathy of Prematurity. Total oxidative status (TOS), total antioxidant status (TAS), malondialdehyde (MDA) and paraoxonase 1 (PON1) activity were determined spectrophotometrically. The values of the pro-oxidants TOS and MDA were significantly higher in infants with ROP as compared to infants without ROP (p<0.05 both). There were no significant differences in the values of TAS and PON1 between the infants with and without ROP. According to study results, TOS and MDA are good markers of oxidative stress, whereas TAS and PON1 activity are unreliable in assessing antioxidant protection.

Tachycardia in a newborn with enterovirus infection.

Enterovirus infections are common in the neonatal period. Newborns are at a higher risk of severe disease including meningoencephalitis, sepsis syndrome, cardiovascular collapse, or hepatitis. The mechanism of heart failure in patients with enterovirus infection remains unknown. Early diagnosis may help clinicians predict complications in those infants initially presenting with severe disease. An 11-day-old male newborn was admitted to our neonatal intensive care unit because of tachycardia and crises of cyanosis. His elder brother had febrile illness. The newborn was cyanotic, in respiratory distress, with tachycardia, low blood pressure and prolonged capillary refilling time. Limb pulse oximeter was around 85%. During the first day of hospitalization, the newborn had one febrile episode. Laboratory data: elevated transaminases, markers of inflammation negative, all bacterial cultures negative. Enterovirus RNA was detected in blood sample. Other blood findings were without significant abnormalities. Electrocardiogram showed tachycardia, with narrow QRS complexes (atrial tachycardia) and heart rate up to 280/min. In order to convert the rhythm, the patient was administered adenosine and amiodarone. In the further course of hospitalization, the patient was in good general condition, eucardiac and eupneic. Newborns with tachycardia and a family history of febrile illness should be suspected to have enterovirus infection. Enterovirus infection is a highly contagious and potentially life-threatening infection if not detected early. The use of sensitive molecular-based amplification methods offers potential benefits for early diagnosis and timely treatment.

Retinopathy of prematurity and serum level of insulin-like growth factor-1.

The aim of our study was to measure and compare serum insulin-like growth factor-1 (IGF-1) levels at postmenstrual age of 33 weeks between preterm infants with and without retinopathy of prematurity (ROP). ROP occurs in two phases. Low serum levels of IGF-1 during ROP phase 1 have been found to correlate with the severity of ROP. ROP phase 2 begins around postmenstrual week 33. We conducted a prospective cohort study to measure serum IGF-1 levels in premature infants at postmenstrual age of 33 weeks. The study included all premature infants (N = 74), gestational age < or = 33 weeks, hospitalized at Department of Neonatology, Clinical Center of Montenegro, from April 2008 to July 2009. The incidence of ROP in the study cohort was 50.7%. Infants with ROP had a significantly lower birth weight and significantly shorter gestational age. The mean level of IGF-1 at postmenstrual age of 33 weeks was 23.7 mcg/L. Study results showed that there was no significant difference in serum IGF-1 level between newborns with and without ROP at postmenstrual age of 33 weeks (in newborns with ROP, it was the beginning of ROP phase 2). A large controlled study with repeated measurement of IGF-1 level in the neonatal period is needed to confirm that restoration of IGF-I level occurs in ROP phase 2, i.e. that the low level of IGF-1 is only a feature of ROP phase 1.

[The values of serum cytokines in chronic lung disease in newborn].

INTRODUCTION: Chronic lung disease in the newborn is a complication of mechanical ventilation. The diagnosis of chronic lung disease is made in children of over 36 post-conceptual weeks' age who still require additional oxygen and who have abnormal chest x-ray findings. This study was aimed at triaging newborns at risk of developing chronic lung disease. The operating study hypothesis was that the values of insulin-like growth factor I below 30 microg/L in the 33rd post-conceptual week were associated with the development of chronic lung disease. MATERIAL AND METHODS: The above hypothesis was verified by a cohort, prospective study, which included preterm newborns of 33 gestational weeks' age or less who were hospitalised at the Department of Neonatology of the Clinical Centre of Montenegro from Aril 2008 to July 2009. The blood sample was taken in the 33rd post-conceptual week and the insulin-like growth factor value was determined by the method of enzyme immunoassay. RESULTS: Our study results confirmed the theory of statistically significant correlation of the length of pregnancy and birth body weight with insulin-like growth factor serum level. DISCUSSION: We did not find any statistically significant correlation between the insulin-like growth factor serum value and chronic lung disease in the newborn. It is possible that the insulin-like growth factor has a different role at various stages of pathogenesis of diseases of prematurity. CONCLUSION: We believe that by correcting the term for determining the levels we can get a significant correlation between low values of insulin-like growth factor -1 and chronic lung disease.