Maternal/neonatal vitamin D deficiency: a new risk factor for necrotizing enterocolitis in preterm infants?

OBJECTIVE: The objective of the study was to investigate the possible association between maternal/neonatal 25-hydroxy vitamin D (25-OHD) levels and development of necrotizing enterocolitis (NEC). STUDY DESIGN: One hundred and forty-five preterm infants ⩽36 weeks of gestation were enrolled. 25-OHD levels were determined in maternal/neonatal blood samples that were obtained at the time of admission to the neonatal intensive care unit. RESULTS: Of the 145 enrolled patients, 26 (18%) developed NEC. Maternal/neonatal 25-OHD levels in the NEC group were significantly lower than those of the no-NEC group (P=0.001 and 0.004, respectively). In univariate logistic regression analysis, both maternal/neonatal vitamin D levels were a significant predictor of NEC (odds ratio (OR): 0.92 and 0.89; P<0.001 and P<0.005, respectively). However, multivariate logistic regression analysis revealed that only maternal vitamin D level was a significant predictor of NEC (OR: 0.86, P<0.0009). CONCLUSION: This is the first study to propose a possible association between maternal/neonatal 25-OHD levels and subsequent development of NEC in preterm infants.

Maternal/neonatal vitamin D deficiency: a risk factor for bronchopulmonary dysplasia in preterms?

OBJECTIVE: The objective of this study was to investigate the possible association between maternal/neonatal 25-hydroxy vitamin D (25-OHD) levels and development of bronchopulmonary dysplasia. STUDY DESIGN: One hundred and thirty-two preterm infants ⩽32 weeks of gestation who were diagnosed with respiratory distress syndrome were enrolled. 25-OHD levels were determined in maternal/neonatal blood samples that were obtained at the time of admission to the neonatal intensive care unit. RESULT: A total of 100 infants were included and 31 (31%) developed bronchopulmonary dysplasia (BPD). Both maternal and neonatal 25-OHD levels in the BPD group were significantly lower compared with those in the no-BPD group (P=0.0001). A positive correlation was detected between maternal and neonatal 25-OHD levels. All of the infants with BPD had a 25-OHD level <10 ng ml(-1), which represented severe deficiency. Univariate logistic regression analysis revealed that maternal/neonatal vitamin D levels were a significant predictor of BPD (odds ratio (OR): 0.76 and 0.61, respectively, P<0.001). CONCLUSION: We demonstrated for the first time that lower maternal and neonatal vitamin 25-OHD levels were associated with BPD development in preterm infants. However, further studies with larger sample sizes are needed to delineate the possible link between vitamin D deficiency and BPD.

Limb deformity in a newborn. Is rifampicin just an innocent bystander?

OBJECTIVE: The first-line antituberculous agents for use during pregnancy have minimal teratogenic effects. The possibility of limb deformity during rifampin use, however, was reported by some researchers. CASE REPORT: A male newborn was born with a hypoplastic right forearm to a mother with tuberculosis who used isoniazid and rifampicin in the first two months of her pregnancy. CONCLUSIONS: The limb anomaly in our case might be attributed to rifampicin usage during the first 2 months of pregnancy. Caution should be given with regard to possible congenital malformations which could be associated with the treatment of pregnant women with antituberculous drugs.

Lower vitamin D levels are associated with increased risk of early-onset neonatal sepsis in term infants.

OBJECTIVE: To evaluate the effect of vitamin D levels on early-onset sepsis (EOS) in term infants. STUDY DESIGN: Fifty term infants with clinical and laboratory findings of EOS (study group) and 50 healthy infants with no signs of clinical/laboratory infection (control group) were enrolled. Blood was drawn at the time of admission during the first 3 postnatal days of life in both groups for measurement of 25-hydroxyvitamin D (25-OHD) levels. RESULT: Maternal and neonatal 25-OHD levels (22.2/8.6 ng ml(-1), respectively) in the study group were significantly lower than those of the control group (36.2/19 ng ml(-1), respectively, P<0.001). A positive correlation was detected between maternal and neonatal 25-OHD levels. Severe vitamin D deficiency was significantly more common in the sepsis group. CONCLUSION: Lower maternal and neonatal 25-OHD levels are associated with EOS. These data suggest that adequate vitamin D supplementation during pregnancy may be helpful to prevent EOS in term neonates.

Coverage of axillary lymph nodes with high tangential fields in breast radiotherapy.

The aim of this study is to evaluate the coverage of axillary nodal volumes with high tangent fields (HTF) in breast radiotherapy and to determine the utility of customised blocking. The treatment plans of 30 consecutive patients with early breast cancer were evaluated. The prescription dose was 50 Gy to the whole breast. Axillary level I-II lymph node volumes were delineated and the cranial border of the tangential fields was set just below the humeral head to create HTF. Dose-volume histograms (DVH) were used to calculate the doses received by axillary nodal volumes. In a second planning set, HTF were modified with multileaf collimators (MLC-HTF) to obtain an adequate dose coverage of axillary nodes. The mean doses of the axillary nodes, the ipsilateral lung and heart were compared between the two plans (HTF vs MLC-HTF) using a paired sample t-test. The doses received by 95% of the breast volumes were not significantly different for the two plans. The doses received by 95% of the level I and II axillary volumes were 16.79 Gy and 11.59 Gy, respectively, for HTF, increasing to 47.2 Gy and 45.03 Gy, respectively, for MLC-HTF. Mean lung doses and per cent volume of the ipsilateral lung receiving 20 Gy (V20) were also increased from 6.47 Gy and 10.47%, respectively, for HTF, to 9.56 Gy and 16.77%, respectively, for MLC-HTF. Our results suggest that HTF do not adequately cover the level I and II axillary lymph node regions. Modification of HTF with MLC is necessary to obtain an adequate coverage of axillary levels without compromising healthy tissue in the majority of the patients.

The application of positron emission tomography/computed tomography in radiation treatment planning: effect on gross target volume definition and treatment management.

AIMS: To analyse the effect of the use of molecular imaging on gross target volume (GTV) definition and treatment management. MATERIALS AND METHODS: Fifty patients with various solid tumours who underwent positron emission tomography (PET)/computed tomography (CT) simulation for radiotherapy planning from 2006 to 2008 were enrolled in this study. First, F-18 fluorodeoxyglucose (FDG)-PET and CT scans of the treatment site in the treatment position and then a whole body scan were carried out with a dedicated PET/CT scanner and fused thereafter. FDG-avid primary tumour and lymph nodes were included into the GTV. A multidisciplinary team defined the target volume, and contouring was carried out by a radiation oncologist using visual methods. To compare the PET/CT-based volumes with CT-based volumes, contours were drawn on CT-only data with the help of site-specific radiologists who were blind to the PET/CT results after a median time of 7 months. RESULTS: In general, our PET/CT volumes were larger than our CT-based volumes. This difference was significant in patients with head and neck cancers. Major changes (> or =25%) in GTV delineation were observed in 44% of patients. In 16% of cases, PET/CT detected incidental second primaries and metastatic disease, changing the treatment strategy from curative to palliative. CONCLUSIONS: Integrating functional imaging with FDG-PET/CT into the radiotherapy planning process resulted in major changes in a significant proportion of our patients. An interdisciplinary approach between imaging and radiation oncology departments is essential in defining the target volumes.

Dosimetric comparison of intensity modulated pelvic radiotherapy with 3D conformal radiotherapy in patients with gynecologic malignancies.

PURPOSE: Before initiating an intensity modulated radiotherapy (IMRT) program for gynecologic malignancies we prospectively evaluated the potential benefits of IMRT by dose volume histogram comparison of IMRT and 3D conformal radiotherapy plans. METHODS: Plans of ten consecutive patients with cervical and endometrial cancer were evaluated. For each patient a 4-field box technique was compared to an IMRT plan. Both plans were normalized to deliver 50.4 Gy to the PTV in six patients and 45 Gy in the remaining four. Isodose distributions and dose volume histograms were compared in seven dose levels. RESULTS: IMRT reduced the volume of small bowel receiving more than 45 Gy in all patients. The average absolute volume of small bowel receiving 45 Gy was significantly reduced from 318 cc to 33 cc. No significant increase in the volume of small bowel receiving less than 20 Gy was observed. Rectum, bladder and bone marrow volumes receiving high doses were also significantly reduced with IMRT. CONCLUSIONS: IMRT significantly reduces the volume of normal tissues irradiated to high doses without compromising the target coverage. This may potentially lead to a reduction in treatment related toxicities.

Solid tumor chemotherapy and in vivo distribution of fluorouracil following administration in poly(L-lactic acid) microspheres.

The physicochemical properties and in vivo distribution of poly(L-lactide) (L-PLA) microspheres containing 5-fluorouracil (5-FU) prepared by a solvent evaporation method were evaluated for potential use in the treatment of liver cancers. Two different molecular weight polymers of L-PLA [L-PLA1 (152,500 Da) and L-PLA2 (52,000 Da)] were used to prepare 5-FU-loaded microspheres. The mean particle size of the microspheres was 3-6 microns, and there was a direct relationship between the mean particle size and the molecular weight of the polymers. The drug release behavior from microspheres exhibited a diffusion mechanism in different dissolution media, with the molecular weight of the polymer being a major factor in controlling the drug release and degradation rates. Following intravenous injection of 99mTc-labeled L-PLA microspheres, with or without 5-FU, or free 5-FU into mice, L-PLA2 microspheres localized mainly in the liver. The disappearance rate of radioactivity from the tissue was very slow in comparison to that of free 5-FU. The results were confirmed by histological examination of liver tissue following administration of fluorescein particles. In addition, growth of a human liver tumor as first transplant generation under the renal capsule of immunocompetent rats and antitumor activity of L-PLA2 microspheres were investigated. Histological examination by optical microscopy showed that there was no neoplastic tissue of the kidney or in other tissues examined after treatment.