Impact of Platelet Count in Retinopathy of Prematurity.

Objectives: The aim of the study was to investigate the risk factors for retinopathy of prematurity (ROP), including platelet count. Materials and Methods: This retrospective study analyzed 137 infants in 3 subgroups: no ROP; mild ROP, and severe ROP requiring laser treatment (type 1 ROP). A retrospective review of records was performed and statistical analysis of possible risk factors for ROP including platelet count was evaluated by using logistic regression. Results: Birth weight (BW), gestational age (GA), and low platelet count in the first week after birth were significant risk factors for developing ROP (p=0.038, 0.02, and 0.004, respectively). BW, GA, ventilation, and lower platelet count were associated with progression to type 1 ROP (p=0.004; 0.027, and 0.021, respectively). Conclusion: Lower platelet count in the first week after birth is a risk factor for ROP development in addition to the previously established factors of ventilation need, low BW, and low GA.

Neonatal effects of thyroid diseases in pregnancy and approach to the infant with increased TSH: Turkish Neonatal and Pediatric Endocrinology and Diabetes Societies consensus report.

Thyroid functions in the fetus and newborn carry importance in terms of the baby's health and development of the central nervous system. Maternaliodine deficiency, exposure to iodine, thyroid diseases (Hashimoto thyroiditis, Graves') and drugs used by the mother affect thyroid functions in the fetus. Reflections of these effects are observed immediately after delivery. Investigation of the mother in terms of thyroid diseases during pregnancy, recognition and appropriate assessment of the required conditions, screening of all newborns in the first days of life in terms of congenital hypothyroidism, timely and appropriate evaluation of the screening results, early diagnosis and appropriate treatment of cases of congenital hypothyroidism, assessment and management of cases of transient thyroid hormone disorders and close monitoring of the thyroid functions and development of patients in whom treatment has been initiated with a diagnosis of hypothyroidism are crucial in terms of developmental outcomes of the babies who have thyroid function disorders or hypothyroidism. This guideline was written with the objective of guiding pediatricians, neonatologists and pediatric endocrinologists in the issue of assessment, diagnosis and management of thyroid function disorders and thyroid diseases concerning the fetus and baby during gestation and neonatal period.

Determination of tissue hypoxia by physicochemical approach in premature anemia.

BACKGROUND: Anemia is a common problem in premature infants and its most rapid and effective therapy is erythrocyte transfusion. However, owing to inherent risks of transfusion in this population, transfusions should be administered only when adequate oxygen delivery to tissues is impaired. The aim of this study was to determine tissue acid levels using Stewart method in an attempt to evaluate the tissue oxygenation level and thereby the accuracy of transfusion timing. METHODS: This study included 47 infants delivered at gestational age below 34 weeks who required erythrocyte transfusion for premature anemia. Strong ion gap (SIG), unmeasurable anions (UMA), tissue acid levels (TA), and Cl/Na ratios were calculated before and after transfusion. RESULTS: The mean birth weight and gestational age of the study population were 1210 ± 365 g and 29.2 ± 2.7 weeks, respectively. Tissue acid levels were increased (TA ≥ 4) and tissue hypoxia developed in 10 (16.6%) of 60 erythrocyte transfusions administered according to the restrictive transfusion approach. The patients were divided into two groups according to tissue acid levels as low (<4) and high (≥4) tissue acid groups. The group with tissue hypoxia (TA ≥ 4) had significantly higher UMA levels but a significantly lower Cl/Na ratio; and UMA levels decreased and Cl/Na ratio increased after transfusion in this group. Tissue hypoxia secondary to anemia was shown to be improved by erythrocyte transfusion. CONCLUSION: The results of the present study suggest that the determination of the level of tissue hypoxia by the Stewart approach may be an alternative to restrictive transfusion guidelines for timing of transfusion in premature anemia. It also showed that a low Cl/Na ratio can be used as a simple marker of tissue hypoxia.

Association of Serum Albumin Level and Mortality in Premature Infants.

BACKGROUND: Hypoalbuminemia has been proven to be a powerful predictor of mortality in adult patients. However, prognostic value of serum albumin in neonates is not clear. OBJECTIVE: To assess the relationship between serum albumin level within the first day of life and outcome in preterm infants born before 32 weeks of gestation. METHODS: The study was conducted prospectively in Baskent University Hospital between October 2008 and November 2009. Patients were divided by gestational age into two groups as below or of 28 weeks and above 28 weeks. Then serum albumin percentile groups were established within each gestational age group and were defined as <25, 25-75, and >75 percentile groups by combining percentile groups between the two gestational age groups. Three serum albumin percentile groups were compared regarding neonatal outcomes. RESULTS: A total of 199 infants with mean birth weight of 1,272 ± 390 g and mean gestational age of 29.2 ± 2.2 weeks were admitted to the study. The mean serum albumin level was 30.6 ± 4.7 g/l for all patients. The mean serum albumin levels were 25.5 ± 3.8, 30.1 ± 2.7, and 35.3 ± 3.7 g/l for <25, 25-75, and >75 percentile groups, respectively. Prevalence of infants with respiratory distress syndrome and prevalence of infants with sepsis and mortality were significantly higher in <25 percentile group. Logistic regression analysis showed that serum albumin <25 percentile and birth weight were independent predictive variables of mortality. Albumin concentrations lower than 27.2 g/l was associated with mortality, with a sensitivity of 71% and a specificity of 86%. CONCLUSION: Low serum albumin level within the first day of life is an independent predictor of mortality in preterm infants.

Is umbilical cord milking always an advantage?

OBJECTIVE: The role of cord milking as an alternative to delayed cord clamping is an area that requires more research. Purpose of this clinical trial was to investigate the impact of umbilical cord milking on the absolute neutrophil counts (ANCs) and the neutropenia frequency of preterm infants. METHODS: Fifty-eight pregnant women were randomly assigned to one of the umbilical cord milking and control groups. A total of 54 preterm infants (gestational age ≤ 32 weeks) were enrolled into the study. The umbilical cords of 25 infants were clamped immediately after birth, and in 29 infants, umbilical cord milking was performed first. RESULTS: The ANCs were statistically significantly lower in the cord milking group compared with the control group on days 1, 3 and 7. The frequency of neutropenia was higher in the cord milking group compared with the control group. CONCLUSION: In our study, ANCs were lower in the cord milking group and the frequency of neutropenia was higher. Umbilical cord milking plays a role on the ANCs of preterm infants.

An aggressive parenteral nutrition protocol improves growth in preterm infants.

The objective of this study was to compare postnatal growth and clinical outcomes of preterm infants after an adjustment in amino acid and lipid administration practice. The study was conducted retrospectively in preterm infants with a birth weight < 1250 g for the periods January-June 2007 and June-November 2010. In 2007, amino acid solution was initiated at 2 g/kg/ day on the first day of life and advanced 1 g/kg/day to a maximum of 3 g/kg/day; lipid solution was initiated at 1 g/kg/day on the first day of life and advanced 0.5 g/kg/day to a maximum of 2 g/kg/day (low-dose parenteral nutrition group). In 2010, amino acid solution was initiated at 3 g/kg/day on the first day of life and advanced 1 g/kg/day to a maximum of 4 g/kg/ day; lipid solution was initiated at 1 g/kg/day on the first day of life and advanced 1 g/kg/day to a maximum of 3 g/kg/day (high-dose parenteral nutrition group). Patient characteristics were similar in the two groups. Infants in the high-dose parenteral nutrition group showed a significant reduction in the time needed to regain birth weight and a significant reduction in the maximum weight loss. Weight, length and head circumference at discharge were significantly higher in the high-dose parenteral nutrition group. The mean duration of parenteral nutrition, mean number of days to reach full enteral feeding and incidence of sepsis and necrotizing enterocolitis were significantly lower in the high-dose parenteral nutrition group. There was no significant difference in the mortality rate between the groups. In conclusion, a more aggressive parenteral nutrition protocol for preterm infants resulted in a more rapid increase in weight, length and head circumference, and decreased incidence of sepsis and necrotizing enterocolitis.

Upper Airway Obstruction in a Newborn with Vallecular Cyst.

Vallecular cyst is a rare cause of stridor in neonates, which may present as a life threatening airway obstruction. Here, we report a preterm infant with a congenital vallecular cyst who presented with stridor and respiratory distress that developed immediately after birth. She was successfully treated with endoscopic marsupialization.

Epidermoid Cyst of Orbit in a Newborn.

A 3-day-old male newborn presented with a severe proptosis of the left eye leading to exposure keratopathy. He underwent debulking of the cyst and biopsy of the tumour and received the pathological diagnosis of epidermoid cyst of orbit. Clinicopathological features of this rare disease are discussed.

Inferior Vena Cava Oxygen Saturation during the First Three Postnatal Days in Preterm Newborns with and without Patent Ductus Arteriosus.

BACKGROUND: Inferior vena cava (IVC) oxygen saturation as an indicator of mixed venous oxygenation may be valuable for understanding postnatal adaptations in newborn infants. It is unknown how this parameter progresses in critically ill premature infants. AIMS: To investigate IVC oxygen saturation during the first three days of life in preterm infants with and without patent ductus arteriosus (PDA). STUDY DESIGN: Case-control study. METHODS: Twenty-seven preterm infants were admitted to the Neonatal Intensive Care. Preterm infants with umbilical venous catheterization were included in the study. Six umbilical venous blood gas values were obtained from each infant during the first 72 hours of life. Preterm infants in the study were divided into two groups. Haemodynamically significant PDA was diagnosed by echocardiography in 11 (41%) infants before the 72(nd) hour of life in the study group and ibuprofen treatment was started, whereas 16 (59%) infants who didn't have haemodynamically significant PDA were included in the control group. RESULTS: In the entire group, the highest value of mean IVC oxygen saturation was 79.9% at the first measurement and the lowest was 64.8% at the 72(nd) hour. Inferior vena cava oxygen saturations were significantly different between the study and control groups. Post-hoc analysis revealed that the first and 36(th) hour measurements made the difference (p=0.01). CONCLUSION: Inferior vena cava oxygen saturation was found to be significantly different between preterm infants with and without PDA. Further studies are needed to understand the effect of foetal shunts on venous oxygenation during postnatal adaptation in newborn infants.

Is it accurate to separate glucose-6-phosphate dehydrogenase activity in neonatal hyperbilirubinemia as deficient and normal?

BACKGROUND: The aim of this study was to investigate glucose 6-phosphate dehydrogenase (G6PD) activity in term and late preterm babies with severe neonatal hyperbilirubinemia and its relationship to the severity and treatment of this disorder, regardless of level of G6PD activity (deficient/normal). METHODS: A total of 529 term and late preterm (≥35 weeks) infants (228 female, 301 male) who were diagnosed with severe hyperbilirubinemia were included in this study. In each case, serum was collected to evaluate blood group, direct Coombs' test, complete blood cell count, total and direct bilirubin, thyroid-stimulating hormone, and G6PD activity. A partial correlation analysis was carried out to assess the relationship between G6PD activity and total bilirubin levels. RESULTS: A significant correlation was found between the severity of hyperbilirubinemia and G6PD activity in both males and females. Male neonates who had G6PD levels <12 U/g Hb required more phototherapy time than neonates who had G6PD levels ≥12 U/g Hb; and female neonates who had G6PD levels <16 U/g Hb required more phototherapy time than neonates who had G6PD levels ≥16 U/g Hb (p < 0.0001). When we analyzed only breastfed infants, a significant difference also emerged in both sexes. Decreased G6PD activity was associated with increased phototherapy time and the need for exchange transfusion. CONCLUSION: Routine checks of G6PD level in hyperbilirubinemic neonates are very important in providing proper medical management to prevent bilirubin-induced neurological dysfunction. Appropriate identification of G6PD (<12 U/g Hb for male infants and <16 U/g Hb for female infants) raises awareness of the severity of the condition and the necessity for immediate care of severe hyperbilirubinemic infants.

"Shunt index" can be used to predict clinically significant patent ductus arteriosus in premature neonates in early post-natal life.

BACKGROUND: This study aimed to examine the differences between arterial and inferior caval vein oxygen saturation, fractional oxygen extraction, and the shunt index, which were calculated in the diagnosis of patent ductus arteriosus. METHODS: Twenty-seven preterm infants were included in this study and were divided into two groups according to patent ductus arteriosus. Among them, 11 (41%) infants had haemodynamically significant patent ductus arteriosus and 16 (59%) did not have significant patent ductus arteriosus. Synchronous arterial and venous blood gases were measured during the first post-natal hours after the insertion of umbilical catheters. The differences between arterial and inferior caval vein oxygen saturation, inferior body fractional oxygen extraction, and the shunt index were calculated. Echocardiography was performed before the 72nd hour of life in a selected group of patients who had haemodynamically significant patent ductus arteriosus. Ibuprofen treatment was administered to patients with patent ductus arteriosus. Echocardiography was performed on the 72nd hour of life in preterm infants without any clinical suspicion of patent ductus arteriosus. RESULTS: The early measured differences between arterial and inferior caval vein oxygen saturation and inferior body fractional oxygen extraction were found to be lower and the shunt index was found to be higher in the haemodynamically significant patent ductus arteriosus group than in the group without haemodynamically significant patent ductus arteriosus. CONCLUSION: We found that the shunt index, calculated in the first hours of life as ≥63%, predicted haemodynamically significant patent ductus arteriosus with a sensitivity of 78% and specificity of 82% in preterm newborns.

Poor postnatal weight gain predicts stage 3+ retinopathy of prematurity in very low birth weight infants.

Multiple systemic risk factors are associated with retinopathy of prematurity (ROP). We analyzed the role of low weight gain (WG) to predict the development of stage 3+ ROP among preterm infants. This study included 126 newborns with birth weight ≤1500 g and gestational age <32 weeks. Preterm newborn infants were divided into two groups according to severity of ROP as: preterm infants without ROP or mild ROP (Group 1) and preterm infants with stage 3+ ROP (Group 2). WG and WG proportion were measured at completed 4 and 6 weeks of life. The patients under the cut-off point according to receiver operating characteristic curve were classified as low WG patients. WG and WG proportion were significantly lower in Group 2 than in Group 1 at the 4th and 6th weeks of life. We concluded that low WG and WG proportion at the 4th and 6th weeks of life were predictive for the development of stage 3+ ROP. Preterm babies with low birth weight and low WG should be followed closely for severe ROP.

Hepatic laceration as a life-threatening complication of umbilical venous catheterization.

Umbilical venous catheterization is an intravenous infusion route for maintenance fluids, medications, blood products, and parenteral nutrition in preterm neonates. However, this procedure may be associated with several complications, such as infection, thrombosis, vessel perforation, and cardiac and hepatic injuries. Hepatic laceration is a rare but life-threatening complication of umbilical venous catheterization that is a result of direct injury through the liver parenchyma. Here, we present a preterm newborn with hepatic laceration as a rare and serious complication of umbilical venous catheterization.

Comparison of UK and US screening criteria for detection of retinopathy of prematurity in a developing nation.

PURPOSE: To determine the incidence, risk factors, and appropriateness of differing guidelines in developed nations for screening for retinopathy of prematurity (ROP) in a single nursery in a large urban city in southern Turkey. METHODS: The records of 260 premature infants born ≤34 weeks in a single tertiary unit were retrospectively reviewed for ROP risk factors and diagnosis. Applicability of UK and US criteria were assessed by the use of receiver operating characteristic curves. RESULTS: ROP of any stage was present in 60 infants (23%); ROP requiring treatment was seen in 30 (11.5%). Univariate analysis showed a significant relationship among the following factors: gestational age, birth weight, total duration of supplemental oxygen, duration of mechanical ventilation, respiratory distress syndrome, anemia, and intraventricular hemorrhage (p < 0.0001). Multiple logistic regression analysis showed gestational age (p = 0.039), birth weight (p = 0.05), respiratory distress syndrome (p = 0.05), and anemia (p = 0.004) as independent predictors of ROP requiring treatment. Area under curve for gestational age alone for diagnosing stage 2 or greater ROP was 0.824 ± 0.03 (p = 0.0001) and for birth weight alone was 0.808 ± 0.03 (p = 0.0001). UK screening criteria detected all stage 2 and greater ROP; US screening criteria missed 2 infants with stage 2 ROP but detected all treatment-requiring disease. Adoption of these screening criteria would have reduced unnecessary examinations by either 21% (UK) or 37% (US). CONCLUSIONS: UK and US criteria improved the detection accuracy for ROP requiring treatment in Turkey and should be studied for other developing nations.

The role of plasminogen activator inhibitor-1 and angiotensin-converting enzyme gene polymorphisms in bronchopulmonary dysplasia.

BACKGROUND: Bronchopulmonary dysplasia (BPD) is a multifactorial disease of preterm infants that is characterized by airway injury, inflammation, and parencymal remodeling. Activation of the coagulation cascade leads to intraalveolar fibrin deposition in many inflammatory pulmonary disorders. Increased fibrin formation or decreased fibrinolysis may cause extravascular fibrin deposition. Extravascular fibrin deposits in septae and alveoli due to the altered fibrin turnover are the pathological hallmarks of BPD, which strongly indicate the importance of the imbalance in the competing activities of coagulation and fibrinolysis. OBJECTIVE: We investigated the predictive value of variations in plasminogen activator inhibitor-1 (PAI-1) and angiotensin-converting enzyme (ACE) genes as molecular determinants for BPD in neonates. METHODS: The study group comprised 98 preterm infants with BPD and a control group including 94 preterm infants without BPD. Restriction fragment size analyses were performed by visualizing digested polymerase chain reaction products for ACE and PAI-1 genotypes. RESULTS: No significant associations were found between ACE, PAI-1 gene polymorphisms, and BPD phenotype in our population. CONCLUSIONS: The two gene polymorphisms (PAI-1 and ACE) had no role in the development of BPD in our study. Further studies with other genes are required for the identification of molecular predisposing factors for BPD that may help in the development of new treatments.

Propranolol for infantile hemangiomas: a preliminary report on efficacy and safety in very low birth weight infants.

Despite the relatively recent introduction of propranolol in the treatment of infantile hemangiomas, there can be little doubt of its efficacy. With regard to safety issues, there are no prior data for very low weight infants. In this study, we used propranolol in preterm and very low weight infants. We used clinical criteria to assess the response to the therapy. We noted all side effects expected from beta-adrenergic blocking drugs, and followed the patients' weight gain during propranolol treatment. Objective, clinical evidence of hemangioma regression was seen after two months in all patients. None of the patients required treatment discontinuation due to adverse side effects. During the propranolol treatment, weight gain was normal in all patients. To the best of our knowledge, this is the first report on the use of propranolol in preterm and very low weight infants, and also the first report from Turkey on the use of propranolol in infantile hemangiomas.

Lack of association between FXIII-Val34Leu, FVII-323 del/ins, and transforming growth factor beta1 (915G/T) gene polymorphisms and bronchopulmonary dysplasia: a single-center study.

Bronchopulmonary dysplasia (BPD) is a multifactorial disease of preterm infants that is characterized by airway injury, inflammation, and parenchymal remodeling. Extravascular fibrin deposits in septae and alveoli due to the altered fibrin turnover are the pathological hallmarks of BPD that strongly indicates the importance of the imbalance in the competing activities of coagulation and fibrinolysis. Activation of the coagulation cascade leads to intraalveolar fibrin deposition in many inflammatory pulmonary disorders. Increased fibrin formation or decreased fibrinolysis may cause extravascular fibrin deposition. We evaluated the association between FXIII-Val34Leu, FVII-323 del/ins, and transforming growth factor beta1 (TGF-beta(1)) (915G/T) gene polymorphisms in patients with BPD. The study group consisted of 98 preterm infants with BPD. Ninety-four of the 192 preterm neonates were without BPD and sampled for the control group. Restriction fragment size analyses were performed by examining digested PCR products for FXIII-Val34Leu, FVII-323 del/ins, and TGF-beta(1) (915G/C) genotypes. No significant associations were found between FXIII-Val34Leu, FVII-323 del/ins, TGF-beta(1) (915G/C) gene polymorphisms and BPD phenotype in our population. Further studies with other genes are required for the identification of molecular predisposing factors for BPD that may help in the development of new treatments and hence might allow for targeting of this treatment to a "high-risk" subgroup, reducing unnecessary exposure to potentially harmful therapies.

Species distribution, antifungal susceptibility and clonal relatedness of Candida isolates from patients in neonatal and pediatric intensive care units at a medical center in Turkey.

The aim of this study was to assess species distribution, antifungal susceptibility and clonal relationships among Candida strains isolated from a group of pediatric/neonatal intensive care (PICU/NICU) patients that had a very high mortality rate (76%). The cases of 21 patients (19 with candidemia, 2 with Candida meningitides) treated over a 1-year period in a Turkish hospital PICU and NICU were retrospectively analyzed. Twenty-eight Candida isolates were detected from blood (20), cerebrospinal fluid (CSF) (2) and other specimens (6). Candida species were identified using the API ID 32C System. Susceptibility testing was done (all 28 isolates) for amphotericin B, fluconazole and itraconazole using the broth microdilution method. Arbitrarily primed polymerase chain reaction (AP-PCR) was used for molecular typing of the 3 most common ones; C. albicans (15), C. parapsilosis (6), and C. pelliculosa (4). Electrophoretic karyotyping (EK) was done to check clonal identity obtained by AP-PCR. Of the 20 blood isolates, 8 (40%) were C. albicans, 12 (60%) were non-albicans Candida, and one of the 2 CSF isolates was C. albicans. The overall species distribution was as follows: 15 C. albicans isolates, 6 C. parapsilosis isolates, 4 C. pelliculosa isolates, 2 C. famata isolates and 1 C tropicalis isolate. Amphotericin B had the best antifungal activity with a MIC90 of 0.125 microg/ml, and the rates of susceptibility to fluconazole and itraconazole were 93% and 82%, respectively. AP-PCR revealed 11 genotypes (4 were identical pairs, 7 were distinct) among the 15 C. albicans isolates, 2 genotypes (5 were classified in the same type) among the 6 C. parapsilosis isolates, and 4 separate genotypes for the 4 C. pelliculosa isolates. Karyotyping results correlated well with the AP-PCR findings. As indicated in the previous research, our results confirmed that non-albicans Candida species have become more frequently causative agents for invasive fungal infections in the ICU. Transmission of C. albicans and C. pelliculosa was relatively low, but transmission of C. parapsilosis was high, suggesting that more effective control and very strict treatment protocols are needed for patients having high mortality and invasive fungal infection in ICU.

Use of balloon-expandable metallic stent in a premature infant with congenital tracheobronchial stenosis.

A congenital tracheobronchial stenosis is a rare obstructive lesion of the airway characterized by intrinsic narrowing of a segment of the trachea and bronchi. In this report, we present the smallest premature infant with a congenital tracheobronchial stenosis who has been successfully treated with balloon dilatation and placement of a balloon-expandable metallic stent.

Effect of feeding type on the efficacy of phototherapy.

OBJECTIVE: The objective of this study was to assess the efficacy of phototherapy for nonhemolytic hyperbilirubinemia and rebound bilirubin levels in breast-fed newborns as compared with mixed-fed (breast milk and formula) newborns. STUDY DESIGN/SETTING: Prospective study of effects of feeding type on response to phototherapy in newborns. METHODS: The subjects were 53 full-term healthy newborns with nonhemolytic hyperbilirubinemia [defined as total serum bilirubin 12 mg/dL (205.2 micromol/L) in the first 48 hours of life or 15 mg/dl (256.5 micromol/L), on subsequent days]. Groups were formed according to type of feeding. Group 1 consisted of 28 breast-fed newborns and group 2 consisted of 25 mixed-fed newborns. Phototherapy was terminated when total serum bilirubin concentration fell to 14 mg/dL (< 239.4 micromol/L). Rebound bilirubin measurements were obtained 24 hours after phototherapy ended. RESULTS: The groups were comparable with respect to age at the start of phototherapy. The amount of weight loss (relative to birth weight) recorded at the start of phototherapy was significantly greater in group 1 than in group 2 (8.1+/- 3.9% vs. 5.4+/- 2.6% p = 0.004). The duration of phototherapy was significantly longer in group 1 than in group 2 (38.6+/- 12.6 h vs. 26.8+/- 9.4 h; P < 0.001). The 24-hour rate of decrease in bilirubin concentration in group 2 was significantly higher than that in group 1 [5.4+/- 2.2 mg/dL/d (92.3+/-37.6 micromol/L/d) vs. 4+/- 1.3 mg/dL/d (68.4+/- 22.2 micromol/L/d); p = 0.01]. The overall rate of decrease in bilirubin concentration in group 1 was significantly lower than that in group 2 [0.16+/- 0.05 mg/dL/h (2.73+/- 0.85 micromol/L/h) vs. 0.22+/- 0.09 mg/dL/h (3.76+/- 1.53 micromol/L/h); p = 0.01]. There was no significant difference between the two groups with respect to rebound bilirubin concentration (P = 0.184). CONCLUSION: Phototherapy effectively reduced bilirubin levels in breastfed newborns with hyperbilirubinemia, but these patients show significantly slower response to this treatment than mixed-fed newborns.