How Food Choices Impact on Male Fertility

PURPOSE OF REVIEW

Increasing evidence on the significance of nutrition in reproduction is emerging from both animal and human studies, suggesting an association between nutrition and male fertility. Here, we have highlighted the impact of the various food groups on reproductive hormones and on spermatogenesis, and the effects of classical and latest dietary patterns such as Mediterranean diet, Western diet, intermittent fasting, ketogenic diet, and vegan/vegetarian diet on male fertility.

RECENT FINDINGS

Nutrients are the precursors of molecules involved in various body's reactions; therefore, their balance is essential to ensure the correct regulation of different systems including the endocrine system. Hormones are strongly influenced by the nutritional status of the individual, and their alteration can lead to dysfunctions or diseases like infertility. In addition, nutrients affect sperm production and spermatogenesis, controlling sexual development, and maintaining secondary sexual characteristics and behaviors. The consumption of fruit, vegetables, fish, processed meats, dairy products, sugars, alcohol, and caffeine importantly impact on male fertility. Among dietary patterns, the Mediterranean diet and the Western diet are most strongly associated with the quality of semen. Nutrients, dietary patterns, and hormonal levels have an impact on male infertility. Therefore, understanding how these factors interact with each other is important for strategies to improve male fertility.

The interplay between macronutrients and sleep: focus on circadian and homeostatic processes

Sleep disturbances are an emerging risk factor for metabolic diseases, for which the burden is particularly worrying worldwide. The importance of sleep for metabolic health is being increasingly recognized, and not only the amount of sleep plays an important role, but also its quality. In this review, we studied the evidence in the literature on macronutrients and their influence on sleep, focusing on the mechanisms that may lay behind this interaction. In particular, we focused on the effects of macronutrients on circadian and homeostatic processes of sleep in preclinical models, and reviewed the evidence of clinical studies in humans. Given the importance of sleep for health, and the role of circadian biology in healthy sleep, it is important to understand how macronutrients regulate circadian clocks and sleep homeostasis.

Weight Loss and Sleep, Current Evidence in Animal Models and Humans

Sleep is a vital process essential for survival. The trend of reduction in the time dedicated to sleep has increased in industrialized countries, together with the dramatic increase in the prevalence of obesity and diabetes. Short sleep may increase the risk of obesity, diabetes and cardiovascular disease, and on the other hand, obesity is associated with sleep disorders, such as obstructive apnea disease, insomnia and excessive daytime sleepiness. Sleep and metabolic disorders are linked; therefore, identifying the physiological and molecular pathways involved in sleep regulation and metabolic homeostasis can play a major role in ameliorating the metabolic health of the individual. Approaches aimed at reducing body weight could provide benefits for both cardiometabolic risk and sleep quality, which indirectly, in turn, may determine an amelioration of the cardiometabolic phenotype of individuals. We revised the literature on weight loss and sleep, focusing on the mechanisms and the molecules that may subtend this relationship in humans as in animal models.

Dynamic Changes of BVRA Protein Levels Occur in Response to Insulin: A Pilot Study in Humans

Biliverdin reductase-A (BVRA) is involved in the regulation of insulin signaling and the maintenance of glucose homeostasis. Previous research showed that BVRA alterations are associated with the aberrant activation of insulin signaling in dysmetabolic conditions. However, whether BVRA protein levels change dynamically within the cells in response to insulin and/or glucose remains an open question. To this aim, we evaluated changes of intracellular BVRA levels in peripheral blood mononuclear cells (PBMC) collected during the oral glucose tolerance test (OGTT) in a group of subjects with different levels of insulin sensitivity. Furthermore, we looked for significant correlations with clinical measures. Our data show that BVRA levels change dynamically during the OGTT in response to insulin, and greater BVRA variations occur in those subjects with lower insulin sensitivity. Changes of BVRA significantly correlate with indexes of increased insulin resistance and insulin secretion (HOMA-IR, HOMA-β, and insulinogenic index). At the multivariate regression analysis, the insulinogenic index independently predicted increased BVRA area under curve (AUC) during the OGTT. This pilot study showed, for the first time, that intracellular BVRA protein levels change in response to insulin during OGTT and are greater in subjects with lower insulin sensitivity, supporting the role of BVR-A in the dynamic regulation of the insulin signaling pathway.

Obesity-Associated Hepatic Steatosis, Somatotropic Axis Impairment, and Ferritin Levels Are Strong Predictors of COVID-19 Severity

The full spectrum of SARS-CoV-2-infected patients has not yet been defined. This study aimed to evaluate which parameters derived from CT, inflammatory, and hormonal markers could explain the clinical variability of COVID-19. We performed a retrospective study including SARS-CoV-2-infected patients hospitalized from March 2020 to May 2021 at the Umberto I Polyclinic of Rome. Patients were divided into four groups according to the degree of respiratory failure. Routine laboratory examinations, BMI, liver steatosis indices, liver CT attenuation, ferritin, and IGF-1 serum levels were assessed and correlated with severity. Analysis of variance between groups showed that patients with worse prognoses had higher BMI and ferritin levels, but lower liver density, albumin, GH, and IGF-1. ROC analysis confirmed the prognostic accuracy of IGF-1 in discriminating between patients who experienced death/severe respiratory failure and those who did not (AUC 0.688, CI: 0.587 to 0.789, p < 0.001). A multivariate analysis considering the degrees of severity of the disease as the dependent variable and ferritin, liver density, and the standard deviation score of IGF-1 as regressors showed that all three parameters were significant predictors. Ferritin, IGF-1, and liver steatosis account for the increased risk of poor prognosis in COVID-19 patients with obesity.

Nonalcoholic fatty liver disease and diabetes

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease in the world and represents a clinical-histopathologic entity where the steatosis component may vary in degree and may or may not have fibrotic progression. The key concept of NAFLD pathogenesis is excessive triglyceride hepatic accumulation because of an imbalance between free fatty acid influx and efflux. Strong epidemiological, biochemical, and therapeutic evidence supports the premise that the primary pathophysiological derangement in most patients with NAFLD is insulin resistance; thus the association between diabetes and NAFLD is widely recognized in the literature. Since NAFLD is the hepatic manifestation of a metabolic disease, it is also associated with a higher cardio-vascular risk. Conventional B-mode ultrasound is widely adopted as a first-line imaging modality for hepatic steatosis, although magnetic resonance imaging represents the gold standard noninvasive modality for quantifying the amount of fat in these patients. Treatment of NAFLD patients depends on the disease severity, ranging from a more benign condition of nonalcoholic fatty liver to nonalcoholic steatohepatitis. Abstinence from alcohol, a Mediterranean diet, and modification of risk factors are recommended for patients suffering from NAFLD to avoid major cardiovascular events, as per all diabetic patients. In addition, weight loss induced by bariatric surgery seems to also be effective in improving liver features, together with the benefits for diabetes control or resolution, dyslipidemia, and hypertension. Finally, liver transplantation represents the ultimate treatment for severe nonalcoholic fatty liver disease and is growing rapidly as a main indication in Western countries. This review offers a comprehensive multidisciplinary approach to NAFLD, highlighting its connection with diabetes.

Growth Hormone Secretory Capacity Is Associated with Cardiac Morphology and Function in Overweight and Obese Patients: A Controlled, Cross-Sectional Study

Obesity is associated with increased cardiovascular morbidity. Adult patients with growth hormone deficiency (GHD) show morpho-functional cardiological alterations. A total of 353 overweight/obese patients are enrolled in the period between 2009 and 2019 to assess the relationships between GH secretory capacity and the metabolic phenotype, cardiovascular risk factors, body composition and cardiac echocardiographic parameters. All patients underwent GHRH + arginine test to evaluate GH secretory capacity, DEXA for body composition assessment and transthoracic echocardiography. Blood samples are also collected for the evaluation of metabolic parameters. In total, 144 patients had GH deficiency and 209 patients had normal GH secretion. In comparing the two groups, we found significant differences in body fat distribution with predominantly visceral adipose tissue accumulation in GHD patients. Metabolic syndrome is more prevalent in the GHD group. In particular, fasting glycemia, triglycerides and systolic and diastolic blood pressure are found to be linearly correlated with GH secretory capacity. Epicardial fat thickness, E/A ratio and indexed ventricular mass are worse in the GHD group. In the population studied, metabolic phenotype, body composition, cardiovascular risk factors and cardiac morphology are found to be related to the GH secretory capacity. GH secretion in the obese patient seems to be an important determinant of metabolic health.

Circulating SIRT1 and Sclerostin Correlates with Bone Status in Young Women with Different Degrees of Adiposity

Sirtuin1 (SIRT1) and sclerostin play important roles in adipose tissue and bone metabolism. We evaluated the circulating SIRT1 and sclerostin relationship with mass and quality of bone while considering the degree of adiposity. Sixty-six premenopausal women (16 underweight, 25 normal weight and 25 with obesity), aged <50 years, were enrolled. Plasma SIRT1, sclerostin and DXA body composition (total fat mass (FM), abdominal visceral adipose tissue, lean mass, trabecular bone score (TBS) and lumbar spine and femoral neck (FN) bone mineral density (BMD)) were assessed. The patients with obesity showed the lowest SIRT1 and TBS values and the highest sclerostin concentrations; BMD increased with FM and BMI and had an inverse association with SIRT1. Sclerostin was negatively correlated with SIRT1 (ρ = −0.37, p = 0.002). When spine BMD, FN BMD and TBS were standardized for BMI, a positive correlation with SIRT1 and a negative correlation with sclerostin were seen (p < 0.005). In the regression analysis, sclerostin was the best independent, negative predictor for BMD and TBS, while SIRT1 directly predicted TBS (p < 0.05). In conclusion, blood measurement of SIRT1 and sclerostin could represent a snapshot of the bone status that, taking into account the degree of adiposity, may reduce the interference of confounding factors in the interpretation of bone health parameters.

Central obesity, smoking habit, and hypertension are associated with lower antibody titres in response to COVID-19 mRNA vaccine

AIMS

To explore variables associated with the serological response following COVID-19 mRNA vaccine.

METHODS

Eighty-six healthcare workers adhering to the vaccination campaign against COVID-19 were enrolled in January-February 2021. All subjects underwent two COVID-19 mRNA vaccine inoculations (Pfizer/BioNTech) separated by 3 weeks. Blood samples were collected before the 1st and 1-4 weeks after the second inoculation. Clinical history, demographics, and vaccine side effects were recorded. Baseline anthropometric parameters were measured, and body composition was performed through dual-energy-X-ray absorptiometry.

RESULTS

Higher waist circumference was associated with lower antibody (Ab) titres (R = -0.324, p = 0.004); smokers had lower levels compared to non-smokers [1099 (1350) vs. 1921 (1375), p = 0.007], as well as hypertensive versus normotensive [650 ± 1192 vs. 1911 (1364), p = 0.001] and dyslipideamic compared to those with normal serum lipids [534 (972) vs 1872 (1406), p = 0.005]. Multivariate analysis showed that higher waist circumference, smoking, hypertension, and longer time elapsed since second vaccine inoculation were associated with lower Ab titres, independent of BMI, age. and gender.

CONCLUSIONS

Central obesity, hypertension, and smoking are associated with lower Ab titres following COVID-19 vaccination. Although it is currently impossible to determine whether lower SARS-CoV-2 Abs lead to higher likelihood of developing COVID-19, it is well-established that neutralizing antibodies correlate with protection against several viruses including SARS-CoV-2. Our findings, therefore, call for a vigilant approach, as subjects with central obesity, hypertension, and smoking could benefit from earlier vaccine boosters or different vaccine schedules.

Ketogenic Diet for Obese COVID-19 Patients: Is Respiratory Disease a Contraindication? A Narrative Review of the Literature on Ketogenic Diet and Respiratory Function

Morbid obese people are more likely to contract SARS-CoV-2 infection and its most severe complications, as need for mechanical ventilation. Ketogenic Diet (KD) is able to induce a fast weight loss preserving lean mass and is particularly interesting as a preventive measure in obese patients. Moreover, KD has anti-inflammatory and immune-modulating properties, which may help in preventing the cytokine storm in infected patients. Respiratory failure is actually considered a contraindication for VLCKD, a very-low calorie form of KD, but in the literature there are some data reporting beneficial effects on respiratory parameters from ketogenic and low-carbohydrate high-fat diets. KD may be helpful in reducing ventilatory requirements in respiratory patients, so it should be considered in specifically addressed clinical trials as an adjuvant therapy for obese patients infected with SARS-CoV-2.

Chronobiology and Metabolism: Is Ketogenic Diet Able to Influence Circadian Rhythm?

Circadian rhythms underpin most physiological processes, including energy metabolism. The core circadian clock consists of a transcription-translation negative feedback loop, and is synchronized to light-dark cycles by virtue of light input from the retina, to the central clock in the suprachiasmatic nucleus in the hypothalamus. All cells in the body have circadian oscillators which are entrained to the central clock by neural and humoral signals. In addition to light entrainment of the central clock in the brain, it now emerges that other stimuli can drive circadian clock function in peripheral tissues, the major one being food. This can then drive the liver clock to be misaligned with the central brain clock, a situation of internal misalignment with metabolic disease consequences. Such misalignment is prevalent, with shift workers making up 20% of the working population. The effects of diet composition on the clock are not completely clarified yet. High-fat diet and fasting influence circadian expression of clock genes, inducing phase-advance and phase-delay in animal models. Ketogenic diet (KD) is able to induce a metabolic switch from carbohydrate to fatty acid oxidation, miming a fasting state. In recent years, some animal studies have been conducted to investigate the ability of the KD to modify circadian gene expression, and demonstrated that the KD alters circadian rhythm and induces a rearrangement of metabolic gene expression. These findings may lead to new approaches to obesity and metabolic pathologies treatment.

La Non-Alcoholic Fatty Liver Disease, una patologia epatica di interesse endocrinologico

La Non-Alcoholic Fatty Liver Disease (NAFLD) comprende diversi stadi di patologia epatica che vanno dalla steatosi alla cirrosi epatica. È considerata la manifestazione epatica della patologia metabolica e alcune alterazioni endocrinologiche possono concorrere a determinarne l’insorgenza o la progressione. È quindi di fondamentale importanza che l’endocrinologo sia consapevole dell’importanza clinica e prognostica della NAFLD correlata alle patologie endocrine, al fine di offrire al paziente il trattamento adeguato.

Ketogenic Diet as a Preventive and Supportive Care for COVID-19 Patients

Severe obesity is associated with an increased risk of admission to intensive care units and need for invasive mechanical ventilation in patients with COVID-19. The association of obesity and COVID-19 prognosis may be related to many different factors, such as chronic systemic inflammation, the predisposition to severe respiratory conditions and viral infections. The ketogenic diet is an approach that can be extremely effective in reducing body weight and visceral fat in the short term, preserving the lean mass and reducing systemic inflammation. Therefore, it is a precious preventive measure for severely obese people and may be considered as an adjuvant therapy for patients with respiratory compromise.

Differential activity and expression of human 5β-reductase (AKR1D1) splice variants

Steroid hormones, including glucocorticoids and androgens, exert a wide variety of effects in the body across almost all tissues. The steroid A-ring 5β-reductase (AKR1D1) is expressed in human liver and testes, and three splice variants have been identified (AKR1D1-001, AKR1D1-002, AKR1D1-006). Amongst these, AKR1D1-002 is the best described; it modulates steroid hormone availability and catalyses an important step in bile acid biosynthesis. However, specific activity and expression of AKR1D1-001 and AKR1D1-006 are unknown. Expression of AKR1D1 variants were measured in human liver biopsies and hepatoma cell lines by qPCR. Their three-dimensional (3D) structures were predicted using in silico approaches. AKR1D1 variants were overexpressed in HEK293 cells, and successful overexpression confirmed by qPCR and Western blotting. Cells were treated with either cortisol, dexamethasone, prednisolone, testosterone or androstenedione, and steroid hormone clearance was measured by mass spectrometry. Glucocorticoid and androgen receptor activation were determined by luciferase reporter assays. AKR1D1-002 and AKR1D1-001 are expressed in human liver, and only AKR1D1-006 is expressed in human testes. Following overexpression, AKR1D1-001 and AKR1D1-006 protein levels were lower than AKR1D1-002, but significantly increased following treatment with the proteasomal inhibitor, MG-132. AKR1D1-002 efficiently metabolised glucocorticoids and androgens and decreased receptor activation. AKR1D1-001 and AKR1D1-006 poorly metabolised dexamethasone, but neither protein metabolised cortisol, prednisolone, testosterone or androstenedione. We have demonstrated the differential expression and role of AKR1D1 variants in steroid hormone clearance and receptor activation in vitro. AKR1D1-002 is the predominant functional protein in steroidogenic and metabolic tissues. In addition, AKR1D1-001 and AKR1D1-006 may have a limited, steroid-specific role in the regulation of dexamethasone action.

The A-ring reduction of 11-ketotestosterone is efficiently catalysed by AKR1D1 and SRD5A2 but not SRD5A1

Testosterone and its 5α-reduced form, 5α-dihydrotestosterone, were previously thought to represent the only active androgens in humans. However, recent studies have shown that the potent androgen, 11-ketotestosterone, derived from the adrenal androgen precursor, 11β-hydroxyandrostenedione, may in fact serve as the primary androgen in healthy women. Yet, despite recent renewed interest in these steroids, their downstream metabolism has remained undetermined. We therefore set out to investigate the metabolism of 11-ketotestosterone by characterising the 5α- or 5β-reduction commitment step. We show that inactivation of 11-ketotestosterone is predominantly driven by AKR1D1, which efficiently catalyses the 5β-reduction of 11-ketotestosterone, committing it to a metabolic pathway that terminates in 11-ketoetiocholanolone. We demonstrate that 5α-reduction of 11-ketotestosterone is catalysed by SRD5A2, but not SRD5A1, and terminates in 11-ketoandrosterone, but is only responsible for a minority of 11-ketotestosterone inactivation. However, as 11-ketoetiocholanolone is also generated by the metabolism of the glucocorticoid cortisone, 11-ketoandrosterone should be considered a more specific urinary marker of 11-ketotestosterone production.

Case Report: Pituitary Morphology and Function Are Preserved in Female Patients With Idiopathic Intracranial Hypertension Under Pharmacological Treatment

Idiopathic Intracranial Hypertension is a neurological disorder primarily affecting overweight women of childbearing age. It is often characterized by radiologic evidence of empty sella (ES), which is in turn frequently associated with pituitary dysfunction, with the somatotropic axis most commonly affected. No recent evidence is available relative to the presence of pituitary hormone deficiencies in adult patients with Idiopathic Intracranial Hypertension (IIH) under pharmacological therapy. We therefore explored pituitary function and morphology in a small cohort of female patients with IIH treated with acetazolamide. Fifteen female patients aged 42 ± 13 years with IIH lasting between 12 and 18 months were evaluated. All patients were affected by recurrent headaches in addition to visual changes of variable severity. IIH diagnosis was made after exclusion of other causes of raised intracranial pressure, and a specific ophthalmological evaluation was conducted to assess for the presence of papilledema. No particular endocrinological disturbances were detected during the enrolment visits, except for a high obesity prevalence (87%, BMI 35.16 ± 8.21 kg/m²), one case of total thyroidectomy for papillary thyroid carcinoma and two patients with irregular menses and mild hirsutism. All the participants underwent a pituitary MRI with contrast, and two different operators performed pituitary measurements in coronal and sagittal scans for morphologic assessment. Blood samples for the anterior pituitary axis evaluation were collected, and the somatotropic axis was further evaluated with a GHRH + Arginine test; other dynamic tests were performed in case of suspected hormonal deficiency. Despite ES being found in 73% of the patients, pituitary volume was preserved, ranging from 213.85 to 642.27mm³ (389.20 ± 125.53mm³); mean coronal pituitary height was 4.53 ± 1.33 mm. Overall, baseline anterior pituitary hormones levels were within normal ranges, and none of the patients with ES had an altered response to the GHRH + arginine stimulation test. We found one patient suffering from iatrogenic hyperthyroidism and two diagnosed with subclinical primary hypothyroidism due to Hashimoto's thyroiditis. Two young patients were suspected of having polycystic ovary syndrome, and they were therefore further investigated. In conclusion, this case series shows that, despite the high prevalence of ES, the pituitary function of IIH patients treated with acetazolamide is preserved. To date, there is no evidence regarding the trend over time or upon treatment discontinuation in regard to the pituitary function of patients with IIH, and it is therefore not possible to infer whether our finding would be replicable in such settings. We therefore suggest an endocrine follow-up over time in order to monitor for potential pituitary dysfunction.

Overweight and obese patients with nickel allergy have a worse metabolic profile compared to weight matched non-allergic individuals

Background

A lack of balance between energy intake and expenditure due to overeating or reduced physical activity does not seem to explain entirely the obesity epidemic we are facing, and further factors are therefore being evaluated. Nickel (Ni) is a ubiquitous heavy metal implied in several health conditions. Regarding this, the European Food Safety Authority has recently released an alert on the possible deleterious effects of dietary Ni on human health given the current levels of Ni dietary intake in some countries. Pre-clinical studies have also suggested its role as an endocrine disruptor and have linked its exposure to energy metabolism and glucose homeostasis dysregulation. Ni allergy is common in the general population, but preliminary data suggest it being even more widespread among overweight patients.

Objectives

The aim of this study has been to evaluate the presence of Ni allergy and its association with the metabolic and endocrine profile in overweight and obese individuals.

Methods

We have evaluated 1128 consecutive overweight and obese outpatients. 784 were suspected of being allergic to Ni and 666 were assessed for it. Presence of Ni allergy and correlation with body mass index (BMI), body composition, metabolic parameters and hormonal levels were evaluated.

Results

We report that Ni allergy is more frequent in presence of weight excess and is associated with worse metabolic parameters and impaired Growth Hormone secretion.

Conclusions

We confirm that Ni allergy is more common in obese patients, and we report for the first time its association with worse metabolic parameters and impaired function of the GH-IGF1 axis in human subjects.

Survival, intracranial lesions, and neurodevelopmental outcome in infants with congenital diaphragmatic hernia treated with extracorporeal membrane oxygenation

OBJECTIVE

Before the use of extracorporeal membrane oxygenation (ECMO), infants with a severe form of congenital diaphragmatic hernia (CDH) had a high mortality and morbidity. Recent studies have shown an improvement in the survival of these infants after ECMO treatment; however, the existing data do not provide sufficient informations regarding the quality of survival and developmental outcome of these infants. The objective of this study was to evaluate survival, intracranial lesions, and the neurodevelopmental outcome of infants with CDH treated with ECMO.

METHODS

We retrieved data for 51 (n = 51) infants with CDH who were treated with ECMO at Huntington Memorial Hospital between 1985 and 1994. Their mean gestational age was 38.5 +/- 2.4 weeks (mean +/- SD); their mean birth weight was 3170 +/- 620 gm. Vital signs, arterial blood gases, chest radiographs, cranial and cardiac ultrasonography were routinely obtained before ECMO treatment. Cranial ultrasounds were performed daily on all infants while on ECMO; computerized tomography scans were obtained on all infants after completion of ECMO treatment. The surviving infants were followed at our neonatal follow-up clinic for neurodevelopmental assessment.

RESULTS

A total of 39 infants were placed on venoarterial ECMO and 12 infants were placed on venovenous ECMO; a total of 35 infants had CDH repair before ECMO, whereas 16 infants had delayed surgery. A total of 31 infants (61%) survived. The infants who survived had a mean pH of 7.33 +/- 0.20, mean airway pressure of 19.6 +/- 5.8 cm H2O, and an oxygenation index (OI) of 87 +/- 55 before ECMO intervention. The infants who expired (n = 20) had a mean pH of 7.31 +/- 0.15, mean airway pressure of 23.1 +/- 5.5 cm H2O, and a mean oxygenation index of 127 +/- 56 before ECMO treatment. Before ECMO, survivors had a significantly lower oxygenation index and a higher Pao2 compared with nonsurvivors (p < 0.01). A total of 18 infants (35%) had abnormal central nervous system findings. Of the 51 infants, 10 had ventricular dilatation, 6 had intracranial hemorrhage, and 11 had focal or diffuse cerebral atrophy diagnosed by computerized tomography scan or at autopsy (1 patient had an infarct). Eight infants had more than one central nervous system abnormality. A total of 16 survivors had a neurodevelopmental evaluation at 12 months, and 11 of these survivors were evaluated at 24 months of age (Bayley Scales of Infant Development). The developmental progress of these infants falls within the low-average range of cognitive and motor abilities. Their mean Bayley Mental Developmental Index was 85 +/- 25 (50 to 145) at 24 months; their Psychomotor Developmental Index was 89 +/- 21 (50 to 113) at 24 months of age. Follow-up at 4 and 6 years of age is in progress.

CONCLUSION

Our preliminary findings indicate that 35% of infants with severe CDH requiring ECMO had central nervous system abnormalities (intracranial lesions, including ventricular dilatation). The survival rate in our study population is consistent with recent reports. As a group, infants with severe CDH display mild neuromotor and cognitive delay in development at 24 months of age.

Predictors of Neonatal Mortality in 1,500–1,999 g Premature Infants with Respiratory Failure

Despite the introduction of new ventilation techniques and surfactant therapy, some premature infants still experience severe respiratory failure and either die or survive with severe bronchopulmonary dysplasia. Extracorporeal membrane oxygenation is currently not offered for preterm infants with a birth weight less than 2,000 g, mainly because of the potential high risk for intracranial hemorrhage. The aim of this study was to determine risk predictors for mortality alone and for mortality or major lung morbidity in 1,500-1,999 g premature infants with respiratory failure. We reviewed the medical records of all preterm infants (n = 459) with respiratory failure and a birth weight of 1,500-1,999 g treated at five medical centers from 1989 to 1991. Of those infants, 23 (5%) had severe respiratory failure, defined as a requirement for ventilatory support with the fraction of inspired oxygen > or = 0.8 or peak inspiratory pressure > or = 30 cmH2O for > or = 3 hr in the 1st week of life. A mortality of > or = 75% was associated with a single arterial/alveolar oxygen ratio < or = 0.04; pulmonary air leak alone or pulmonary air leak with a mean airway pressure > or = 12 cmH2O; and arterial oxygen tension < or = 50 mmHg. These risk predictors may provide a basis for the selection of patients for future clinical trials of extracorporeal membrane oxygenation in this high-risk group of 1,500-1,999 g premature infants with severe respiratory failure.

Predictors of neonatal mortality in 1,500-1,999 g premature infants with respiratory failure. Basis for ECMO Therapeutic Trial

Despite the introduction of new ventilation techniques and surfactant therapy, some premature infants still experience severe respiratory failure and either die or survive with severe bronchopulmonary dysplasia. Extracorporeal membrane oxygenation is currently not offered for preterm infants with a birth weight less than 2,000 g, mainly because of the potential high risk for intracranial hemorrhage. The aim of this study was to determine risk predictors for mortality alone and for mortality or major lung morbidity in 1,500-1,999 g premature infants with respiratory failure. We reviewed the medical records of all preterm infants (n = 459) with respiratory failure and a birth weight of 1,500-1,999 g treated at five medical centers from 1989 to 1991. Of those infants, 23 (5%) had severe respiratory failure, defined as a requirement for ventilatory support with the fraction of inspired oxygen > or = 0.8 or peak inspiratory pressure > or = 30 cmH2O for > or = 3 hr in the 1st week of life. A mortality of > or = 75% was associated with a single arterial/alveolar oxygen ratio < or = 0.04; pulmonary air leak alone or pulmonary air leak with a mean airway pressure > or = 12 cmH2O; and arterial oxygen tension < or = 50 mmHg. These risk predictors may provide a basis for the selection of patients for future clinical trials of extracorporeal membrane oxygenation in this high-risk group of 1,500-1,999 g premature infants with severe respiratory failure.

Congenital pulmonary alveolar proteinosis: failure of treatment with extracorporeal life support

Pulmonary alveolar proteinosis, a rare disease in neonates, is characterized by the accumulation of insoluble amorphous material within the alveoli. We describe two pairs of siblings with pulmonary alveolar proteinosis in two otherwise unaffected families. All four patients were term neonates in whom severe pulmonary failure developed within hours after birth; three had mature lung profiles. Radiographic lung markings were characterized by an early granular pattern followed by lung opacification. All patients were treated with extracorporeal life support for periods of 212 to 381 hours, but none survived. Life spans ranged from 16 to 190 days. We speculate that pulmonary alveolar proteinosis in neonates results from a genetic defect in surfactant processing that may not be amenable to conventional or unconventional therapies, including extracorporeal life support.

Ventilation parameters and arterial blood gases as a prediction of hypoplasia in congenital diaphragmatic hernia

Attempts to predict the degree of pulmonary hypoplasia associated with congenital diaphragmatic hernia have been made by evaluating the ventilation parameters and the arterial blood gasses of these patients. A CO2 index as a predictor of outcome, which correlates the PaCO2 with the ventilation index, was recently proposed. However, in this study the postductal PaO2 was a better predictor of survival. And the so-called "honeymoon period" was a better indicator of the efficacy of extracorporeal membrane oxygenation (ECMO) than the CO2 index. Nineteen patients were evaluated; 11 were treated with ECMO, and eight were not considered suitable for ECMO.

Oxygenation index in patients with meconium aspiration: conventional and extracorporeal membrane oxygenation therapy

The use of the alveolar-arterial oxygen difference P(A-a)O2 and the oxygenation index (mean airway pressure [Paw] FIO2 x 100/PaO2) have been proposed for selecting infants who will require extracorporeal membrane oxygenation (ECMO) therapy. However, the use of the oxygenation index (OI) in conjunction with Paw in an exclusive population of patients with meconium aspiration syndrome (MAS) has not been reported. Fourteen patients born in our facility and managed with conventional therapy and five infants treated with ECMO were enrolled in the study. All patients had clinical and x-ray evidence of MAS. Infants who received conventional treatment required mechanical ventilation greater than 48 h, FIO2 1.0, and were under the care and supervision of one neonatologist. Management was directed to minimize barotrauma by avoidance of routine hyperventilation, use of lower Paw, and sufficient expiratory time. One patient died before ECMO and 13 infants survived. Six survivors had an OI greater than 25 (three had an OI greater than 40), six had a Paw greater than or equal to 12 cm H2O (12 to 15 cm H2O in five infants) and six patients had a P(A-a)O2 greater than or equal to 610 torr. One surviving infant was transferred for ECMO therapy (OI 67, Paw 20 cm H2O). The five patients treated with ECMO survived (OI 48 to 92, Paw 20 to 29.5 cm H2O P(A-a)O2 627 to 650 torr). One patient in each group developed chronic lung disease with evidence of resting tachypnea. Our findings indicate that an OI greater than 40 in association with a Paw greater than or equal to 20 cm H2O may be helpful in predicting which infants with MAS need ECMO, whereas patients requiring a Paw less than or equal to 15 cm H2O can be managed with conventional therapy. An OI greater than or equal to 25 but less than 40 is not associated with high mortality in these patients. The predictive value of Paw of 16 to 20 cm H2O and the duration of an OI greater than 40 in patients with MAS need further investigation.

Color Doppler imaging of intracranial vessels in the neonate

This study was performed to examine the effectiveness of color Doppler imaging (CDI) in demonstrating the neonatal intracranial vessels and altered intracranial flow patterns and to determine the optimal approach in imaging and intracranial vasculature. The study was conducted in two parts. First, 14 neonates were examined with CDI by using a standard approach through the anterior fontanel. Whenever possible, views through the posterior fontanel and the temporal bone were obtained also. The anterior cerebral, M1 segment of the middle cerebral, distal internal carotid, and basilar arteries were demonstrated consistently. Portions of the vertebral distal middle cerebral, and posterior cerebral arteries were frequently visualized. In the second part of the study, we examined 10 neonates who had undergone extracorporeal membrane oxygenation. In this group of patients, CDI was able to demonstrate occlusion of the right internal carotid artery and the reversal of flow through the ipsilateral A1 segment. Increased flow on the contralateral side and in the basilar artery was observed in several patients. The anterior fontanel approach was shown to be the most useful in identifying most of the major intracranial arteries and veins with CDI. In addition, the body weights and gestational ages of the neonates were found to significantly influence the success rate in visualizing the intracranial vasculature.

Clinical use of extracorporeal membrane oxygenation in the treatment of persistent pulmonary hypertension following surgical repair of congenital diaphragmatic hernia

The clinical use of extracorporeal membrane oxygenation (ECMO) in the treatment of persistent pulmonary hypertension following surgical repair of congenital diaphragmatic hernia is reported on 11 patients. The patients had a total of 13 treatments; two patients had two treatments. During the same period of clinical use, 122 patients were placed on ECMO for all causes. The indications, results, and complications of the use of ECMO for treatment following surgical repair of congenital diaphragmatic hernia are presented. The reversal of persistent pulmonary hypertension is demonstrated. All patients treated by ECMO for congenital diaphragmatic hernia have survived.