Sonography of the circumrenal and horseshoe adrenal gland in the newborn

The adrenal gland can be visualized using ultrasonography in at least 90% of fetuses of more than 26 weeks gestation. The fetal and neonatal adrenal gland is described as a structure having a characteristic V or Y shape. Despite the frequency of visualization of the neonatal adrenal gland, few reports of adrenal anomalies are present in the radiologic literature. The purpose of this paper is to describe and depict the sonographic appearance of the horsedhoe and the circumrenal adrenal gland and to discuss adrenal anomalies in general.     

Ultrasound of the thyroid gland in the newborn: normative data

OBJECTIVE: To establish reference ranges for thyroid length, breadth, depth, and volume in healthy term Scottish infants. DESIGN: Prospective observational study of 100 (49 male) neonates. Length, breadth, and depth were measured, and the volume of each lobe was calculated using the formula for a prolate ellipsoid (volume = length x breadth x depth x pi/6). RESULTS: All measurements showed gaussian distribution, with no significant differences between the right and the left lobes. Values (mean (SD) range) were: length (cm), 1.94 (0.24) 0.9-2.5; breadth (cm), 0.88 (0.16) 0.5-1.4; depth (cm), 0.96 (0.17) 0.6-2.0; volume (ml), 0.81 (0.24) 0.3-1.7; combined volume (ml), 1.62 (0.41) 0.7-3.3. Although there was no difference in mean volume between right and left lobes, there was considerable variation (-0.8 to + 0.7 ml) between the two lobes in individual babies. CONCLUSIONS: Both lobes should be measured to give a combined volume. Our findings provide a reference against which thyroid hypoplasia or goitre can be evaluated.     

Is sebaceous gland hypertrophy in the newborn androgen induced?

Sebaceous gland hypertrophy is almost always present on the face of newborn infants and yet its aetiology is obscure. Androgens, either maternal or fetal, are thought to be related to its development. In a study of the extent and distribution of sebaceous gland hypertrophy in 115 newborn infants, it was found that there was no difference between males and females, and that the condition was more extensive in preterm infants. As circulating testosterone levels are higher in male newborns, and as maternal androgen excretion increases as pregnancy progresses, it is concluded that the appearance of sebaceous gland hypertrophy at birth is independent of androgens and may well be a developmental stage in the maturation of the skin.     

The thyroid gland of the newborn infant and postnatal iodine overload]

Severe iodine-induced hypothyroidism was recently diagnosed in several neonates raising the responsibility of the iodine antiseptic agents routinely used in these patients. Postnatal iodine overload due to cutaneous application of these agents (povidone iodine and fluorescinated alcoholic-iodine solution) was studied in 5 patients. Thyroid function studies were performed in iodine-overload neonates and in control neonates with comparable gestional age. Results indicated strong evidence of cutaneous absorption of iodine from the antiseptic agents used, leading to hypothyroidism in 12 of them. The frequency and the severity of thyroid dysfunction was closely related to the degree of prematurity. Full recovery was observed in all cases after withdrawal of the iodine-containing agents. It is therefore recommended to avoid any postnatal use of iodine preparations in neonates, mainly in preterm infants, and to use iodine antiseptic agents with great caution, when necessary during the neonatal period.     

Smoking during pregnancy--hematological observations in the newborn

Hematological values were measured in 28 newborn infants of mothers smoking 10-20 cigarettes daily during pregnancy, and in 25 infants of non-smokers. Higher hematocrit levels were found on the 1st day of life in infants of smoking mothers (60.8 +/- 5.0%, mean +/- S.D.) compared to controls (57.5 +/- 4.8%) (p less than 0.05). The hematocrit levels correlated positively with the maternal smoking level (r = 0.318, p less than 0.05) and the maternal serum thiocyanate concentrations at delivery (r = 0.389, p less than 0.01). Cord serum values for erythropoietin, serum-iron, transferrin and ferritin showed no statistically significant difference between the two groups. A significant inverse correlation was found between the hematocrit value on the 1st day of life and the cord serum ferritin concentration (r = -0.495, p less than 0.005). The present results suggest that maternal smoking stimulates fetal erythropoiesis, probably through a hypoxic effect on the fetus, dose related to the maternal smoking level. Increased erythropoiesis may cause increased iron incorporation into erythrocytes at expense of iron storage in the bone marrow and reticuloendothelial system.     

Human lactation. II: Endogenous fatty acid synthesis by the mammary gland

We studied the effects of a diet that was low in fat, high in carbohydrate (CHO) on milk lipid composition and de novo endogenous fatty acid synthesis by the mammary gland in five lactating women. The women consumed either a low fat (LF) (5% fat, 80% CHO) diet or a high fat (HF) (40% fat, 45% CHO) diet. Fat synthesis was determined after an oral dose of 500 mg/kg D2O by measuring the incorporation of deuterium into C10:0 to C18:0 saturated fatty acids of milk fat and plasma triglycerides by gas chromatography-mass spectrometry. Synthesis of plasma C16:0 and C18:0 triglycerides was barely detectable while women consumed the HF diet, but was increased 6-fold during the LF diet. Medium chain fatty acids secreted by the mammary gland increased from 12.8% (HF diet) to 16.3% (LF diet) in milk fat from four of five subjects (p = 0.027). Medium chain fatty acid secretion, however, increased from 13.9% (HF diet) to 29.9% (LF diet) in one subject. The primary fatty acids synthesized during lactation were C10:0, C12:0, and C14:0 in the majority of women studied. The LF diet significantly increased the apparent synthesis of C14:0 (p = 0.05), whereas no changes were observed in C12:0, C16:0, or C18:0. One subject had highly enriched C16:0 and C18:0 fatty acids in her milk on the LF diet, which could have been the result of mammary synthesis or of transport and secretion of hepatically synthesized lipids.     

Net sodium and water movements in the newborn rabbit collecting tubule: lack of modifications by indomethacin

In contrast to adult tubules, a bath-to-lumen sodium gradient was followed by net sodium entry in the lumen of in vitro isolated perfused newborn (3-5 days) rabbit collecting tubules. In addition, transepithelial voltage and electrical resistance were lower in newborn tubules. The sodium flux into the lumen was unaffected by indomethacin. These observations suggest that the newborn collecting tubule may be unable to maintain an adequate sodium gradient for the optimal function of the urinary concentrating mechanism, and that endogenous prostaglandins are not involved in this defect.     

Local complement genes expression in the mammary gland: effect of gestation and inflammation.

Complement components in breast milk may enhance the local immune response in the gut of infants. In this study, we investigated the expression of complement genes in the mammary gland and attempted to determine possible regulatory mechanisms. We have studied the expression of C3, C4, factor B, and HLA-DRalpha mRNA by in situ hybridization in gestational mammary gland specimens and compared these findings to those in breast tissue affected with an inflammatory process, lactating adenoma or idiopathic gynecomastia. In normal resting breast, only C4 mRNA was noted in some ductal epithelium. In gestational mammary gland, there was a diffuse expression of C4, C3, and factor B mRNA in the epithelial cells of the acini. A similar pattern of complement gene expression was found in localized areas of an infectious inflammatory process. In addition, in the inflammatory specimens, there was also expression of C3 mRNA in infiltrating macrophages (CD 68 positive cells). In gynecomastia, C4 mRNA was noted in ductal epithelium, and there was a marked increased expression of C3 mRNA in the proliferating epithelium of the lactating adenoma. HLA-DRalpha was observed only in macrophages involved in the inflammatory response. Our findings, which reflect the hormonal and inflammatory events in vivo, provide new insights as to in situ complement gene expression.     

Neurological condition of large-for-gestational-age infants during the newborn period

Thirty-two large-for-gestational-age (LGA) infants and 46 appropriate-for-gestational-age (AGA) infants used as controls, were investigated. LGA and AGA infants did not differ regarding instrumental deliveries or asphyxia. The infants were examined on the 1st and 5th days after birth with a standardized neurological assessment. The LGA infants showed a significantly delayed neurological adaptation with fewer optimal responses on day one as compared to the AGA infants. These differences were not observed on day five. There were no neurological differences between prenatally and postnatally detected LGA infants. No significant differences were observed regarding parity on maternal complications, neonatal course, and neurological scores of the LGA infants.     

Adrenal haemorrhage with cholestasis and adrenal crisis in a newborn of a diabetic mother

The large hyperaemic foetal adrenal gland is vulnerable to vascular damage. This may occur in the neonatal period as a consequence of difficult labour, or its aetiology may not be apparent. The spectrum of presentation is considerable, ranging from asymptomatic to severe life-threatening intra-abdominal haemorrhage. The presentation of adrenal insufficiency may be delayed but the regenerative capacity of the adrenal is great, and most adrenal haemorrhage is not associated with significantly impaired function. Some reports showed that cholestatic hepatopathy with congenital hypopituitarism reversed by hydrocortisone treatment is considered in the context of the endocrine syndrome, probably as a consequence of the adrenal failure. We describe a case of bilateral adrenal haemorrhage with hepatitis syndrome and persistent hypoglycaemia in a newborn male with striking features of neonatal cholestasis and adrenal crisis.