Study of the pathophysiological mechanisms associated with the onset and course of neurodevelopmental disorders in preterm infants (the PeriSTRESS-PremTEA study): Rationale, objectives, design and sample description

BACKGROUND

There are few studies exploring the pathophysiological pathways that may condition differentially the emergence/course of neurodevelopmental disorders (ND) in very preterm and extremely preterm newborns (VPTN/EPTN). Furthermore, there are no established biological markers predictive of ND in this population. The aim of this study is four-fold: in two cohorts of VPTN/EPTN (i) to characterize the emergence/course of ND up to corrected-age 6 years, (ii) to identify those factors (from prenatal stages up to age 6 years) that explain the interindividual differences related to emergence/course of ND, (iii) to identify in the first hours/days of life a urinary metabolomic biomarker profile predictive of ND, and (iv) to determine longitudinally variations in DNA methylation patterns predictive of ND.

METHODS

Observational, longitudinal, prospective, six-year follow-up, multicentre collaborative study. Two cohorts are being recruited: the PeriSTRESS-Valencia-cohort (n=26 VPTN, 18 EPTN, and 122 born-at-term controls), and the PremTEA-Madrid-cohort (n=49 EPTN and n=29 controls).

RESULTS

We describe the rationale, objectives and design of the PeriSTRESS-PremTEA project and show a description at birth of the recruited samples.

CONCLUSIONS

The PeriSTRESS-PremTEA project could help improve early identification of clinical, environmental and biological variables involved in the physiopathology of ND in VPTN/EPTN. It could also help to improve the early identification of non-invasive ND biomarkers in this population. This may allow early ND detection as well as early and personalised intervention for these children.

Temperamental and psychomotor predictors of ADHD symptoms in children born after a threatened preterm labour: a 6-year follow-up study

Children born after threatened preterm labour (TPL), regardless of whether it ends in preterm birth, may represent an undescribed "ADHD cluster". The aim of this cohort study is to identify early temperament and psychomotor manifestations and risk factors of TPL children who present ADHD symptoms. One hundred and seventeen mother-child pairs were followed from TPL diagnosis until the child's 6 years of life. TPL children were divided according to the prematurity status into three groups: full-term TPL (n = 26), late-preterm TPL (n = 53), and very-preterm TPL (n = 38). A non-TPL group (n = 50) served as control. Temperament and psychomotor development at age 6 months and ADHD symptoms at age 6 years were assessed. Perinatal and psychosocial factors were also recorded. All TPL groups showed higher severity of ADHD symptoms compared with non-TPL children (difference in means + 4.19 for the full-term group, + 3.64 for the late-preterm group, and  + 4.99 for the very-preterm group, all ps < 0.021). Concretely, very-preterm and late-preterm TPL children showed higher restless/impulsive behaviours, whereas full-term TPL children showed higher emotional lability behaviours. Higher surgency/extraversion and delayed fine motor skills at age 6 months predicted ADHD symptoms at 6 years in TPL children. Male sex, maternal state anxiety symptoms at TPL diagnosis, low parental education, and past maternal experience of traumatic events predicted higher ADHD symptoms in TPL children. Therefore, TPL children may have a higher risk for developing ADHD symptoms, presenting a phenotype that depends on the prematurity status. Moreover, the specific combination of early manifestations and risk factors suggests that TPL children may conform an undescribed group at-risk of ADHD symptoms.

The effects of reward and frustration on the task performance of autistic children and adolescents

BACKGROUND

Autistic individuals often exhibit social communication and socio-emotional styles that may interfere with achieving social and academic outcomes. At a more specific level, they may perform differently in various social and academic tasks due to different modes of processing rewards or unpleasant experiences (e.g., frustrating events).

AIM

The present experiment examines how rewards and frustration affect the task performance of autistic children and adolescents METHODS AND PROCEDURES: An affective Posner task was applied to introduce rewards and induce frustration. Forty-four autistic children and adolescents and forty-four typically developing (TD) peers participated in this study OUTCOMES AND RESULTS: Results showed that presenting social and non-social rewards resulted in shorter reaction times and lower error rates in autistic participants, but not in their TD peers. While frustration increased error rates in both autistic and TD individuals, the effect was more pronounced in the autistic group.

CONCLUSIONS AND IMPLICATIONS

Social and non-social rewards help the performance of autistic children and adolescents, whereas frustration (induced through unpredictable feedback) significantly interferes with their task performance. Therefore, receiving two types of rewards and providing predictable feedback may help to improve interventions designed to optimize task performance for autistic children and adolescents.

Rescue doses of antenatal corticosteroids, children's neurodevelopment, and salivary cortisol after a threatened preterm labor: a 30-month follow-up study

BACKGROUND

Antenatal corticosteroids reduce neonatal complications when administered to women at risk for preterm birth. Moreover, antenatal corticosteroid rescue doses are recommended for women who remain at risk after the initial course. However, there is controversy about the most appropriate frequency and the exact timing of administering additional antenatal corticosteroid doses because there are potential long-term negative effects on infants' neurodevelopment and physiological stress functioning.

OBJECTIVE

This study aimed to (1) to assess the long-term neurodevelopmental effects of receiving antenatal corticosteroid rescue doses in comparison with receiving only the initial course; (2) to measure the cortisol levels of infants of mothers who received antenatal corticosteroid rescue doses; (3) to examine a potential dose-response effect of the number of antenatal corticosteroid rescue doses on children's neurodevelopment and salivary cortisol.

STUDY DESIGN

This study followed 110 mother-infant pairs who underwent a spontaneous episode of threatened preterm labor until the children were 30 months old, regardless of their gestational age at birth. Among the participants, 61 received only the initial course of corticosteroids (no rescue dose group), and 49 participants required at least one rescue dose of corticosteroids (rescue doses group). The follow-up was carried out at 3 different times, namely at threatened preterm labor diagnosis (T1), when the children were 6 months of age (T2), and when the children were 30 months of corrected age for prematurity (T3). Neurodevelopment was assessed using the Ages & Stages Questionnaires, Third Edition. Saliva samples were collected for cortisol level determination.

RESULTS

First, the rescue doses group showed lower problem-solving skills at 30 months of age than the no rescue doses group. Second, the rescue doses group demonstrated higher salivary cortisol levels at 30 months of age. Third, a dose-response effect was found that indicated that the more rescue doses the rescue doses group received, the lower the problem-solving skills and the higher the salivary cortisol levels at 30 months of age.

CONCLUSION

Our findings reinforce the hypothesis that additional antenatal corticosteroid doses provided after the initial course may have long-term effects on the neurodevelopment and glucocorticoid metabolism of the offspring. In this regard, the results raise concerns about the negative effects of repeated doses of antenatal corticosteroids in addition to a full course. Further studies are necessary to confirm this hypothesis to help physicians reassess the standard antenatal corticosteroid treatment regimens.

Are infants born after an episode of suspected preterm labor at risk of attention deficit hyperactivity disorder? A 30-month follow-up study

BACKGROUND

An episode of suspected preterm labor may be by itself a pathologic event that may alter the normal course of pregnancy and the offspring's neurodevelopment. Certainly, the association between preterm birth and neurodevelopmental disorders can only be partially explained by the immaturity of the nervous system, as evidenced by the increased risk of attention deficit hyperactivity disorder in late-preterm infants without any neurologic alteration.

OBJECTIVE

This study aimed to examine whether infants born after suspected preterm labor may be at an increased risk of developing attention deficit hyperactivity disorder. Moreover, potential obstetrical, perinatal, and psychosocial risk factors associated with attention deficit hyperactivity disorder in this population are examined.

STUDY DESIGN

A prospective cohort study of 120 mother-infant pairs was conducted from the moment the mothers received a diagnosis of suspected preterm labor until the infants' 30 months of life. Infants were divided according to the prematurity status: full-term infants born after a suspected preterm labor (n=28; born at ≥37 weeks of gestation), late-preterm infants (n=56; born between 32 and <37 weeks of gestation), very-preterm infants (n=36; born before <32 weeks of gestation). At-term infants born without obstetric complications served as a control group (n=46). Infants' attention deficit hyperactivity disorder symptoms were assessed at the age of 30 months. Furthermore, obstetrical, perinatal, and psychosocial risk factors were recorded.

RESULTS

All groups of infants born after a suspected preterm labor showed more attention deficit hyperactivity disorder symptoms at the age of 30 months than the control group. Concretely, very-preterm infants showed higher restless or impulsive behaviors, whereas full-term infants born after a suspected preterm labor and late-preterm infants showed higher emotional lability behaviors. Among potential risk factors, male sex and maternal experience of posttraumatic stress symptoms predicted the severity of attention deficit hyperactivity disorder symptoms in infants born after a suspected preterm labor.

CONCLUSION

Infants born after a suspected preterm labor had a higher risk of developing attention deficit hyperactivity disorder symptoms, including those born at term. Infants born after a suspected preterm labor showed a distinctive phenotype and shared specific risk factors suggesting that they conform an undescribed population at risk of attention deficit hyperactivity disorder.

Biological determinants of functioning in euthymic patients with Bipolar Disorder: A multicentric 3-year cohort study

Introduction

Bipolar disorder is related with functional impairment in euthymia. The contribution of biological functions such as sleep, sexual functioning; or the presence of obesity on this loss remain understudied.

Objectives

The aim of this work was to study the influence of biological determinants in context with clinical and demographical determinants of functioning in a 3-year cohort of euthymic BD patients.

Methods

In this multicentric study 67 euthymic adult bipolar outpatients were followed during three years. Functioning was assessed with FAST, insomnia severity with Oviedo Sleep Questionnaire (OSQ) and, sexual functioning with Changes on Sexual Functioning Questionnaire (CSFQ-14) and obesity was expressed as body mass index (BMI). The basal effect of sleep, sexual functioning and obesity (Time 0) on FAST (Time 3) was analyzed with a mixed ordinal regression model including time effect, age, sex, number of manic and depressive episodes, euthymia length, and comorbidity with personality disorder. Change in functioning (Time 3 to 0) was analyzed in another mixed model also considering the difference in biological determinants (Time 3 to 0) and the presence of mood episodes during the period.

Results

A basal worse sexual functioning, a higher severity of insomnia and a higher BMI predicted a worse functioning at three years (p=0.005, p=0.043, p=0.05 respectively). Regarding FAST difference from Time0 to 3, only having a manic episode related to an impairment on functioning (p=0.027).

Conclusions

Sexual functioning, quality of sleep and BMI are predictors of functioning in euthymia in BD. Manic episodes in the following contribute to impairments on functioning more than depressive episodes.

Disclosure

No significant relationships.

Study Protocol: Gut microbiota profiles implicated in the onset of autism spectrum disorders in preterm infants: A two-year follow-up study

Introduction

Preterm infants are at high-risk of developing autism spectrum disorders (ASD). The underlying mechanisms that explain the link between prematurity and ASD are unclear. Perinatal environmental factors may disrupt the gut-brain communication, when the gut microbiome composition is established and brain programming occurs. Therefore, the disruption of the gut-brain axis communication in response to perinatal environmental events may shed light on the association between prematurity and ASD.

Objectives

To describe a new research project protocol which aim is to develop a dynamic model of gut microbiota variation in response to environmental factors that modulate the ASD risk in preterm infants.

Methods

A two-year prospective observational study will be carried out, in which preterm infants will be assessed at birth, 40th postmenstrual week, at 6, 12, and 24 months of corrected age. Two-hundred preterm infants will be recruited. A comprehensive assessment will be conducted by collecting data on sociodemographic characteristics, medical history, family functioning, neurodevelopment, ASD screening, and diagnosis. Microbiome composition and microbial activity will be determined from feces.

Results

The expected results are: i) to characterize ASD since its early manifestations in an at-risk population, allowing an early diagnosis and intervention to improve clinical outcomes; ii) to identify early microbiota biomarkers in order to find potential pathophysiological pathways; iii) to understand the protective and risk factors associated to ASD since perinatal period.

Conclusions

A two-year predictive model will be generated based on environmental and gut microbiota variables. This predictive model of ASD would allow prevention, early diagnosis, improvement of prognosis, and personalized treatments in preterm infants.

Disclosure

No significant relationships.

Affective temperaments and sexual functioning in euthymic patients with bipolar disorder

Sexual functioning in bipolar disorder (BD) is dependent on multiple clinical and demographic determinants that can eventually lead to sexual dysfunction. However, the contribution of affective temperaments remains unstudied in this population. In this cross-sectional multicentric work, we studied the impact of temperament traits on sexual functioning in 100 euthymic BD outpatients treated only with mood stabilizers with or without benzodiazepines. Temperament was evaluated using the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego - Autoquestionnaire (TEMPS-A) and sexual functioning with the Changes on Sexual Functioning Questionnaire (CSFQ-14). The effect of temperament on sexual functioning was analyzed using Bayesian ordinal regression models, which included age, gender, BD type, dominant polarity, metabolic syndrome, marital status, and affective symptomatology. Our results showed that hyperthymic traits predicted a significantly higher CSFQ-14 score for global sexual functioning (OR = 1.222; 95% CI [1.073, 1.431]), desire (OR = 1.164; 95% CI [1.025, 1.357]), arousal (OR = 1.278; 95% CI: [1.083, 1.551]), and orgasm (OR = 1.182; 95% CI [1.037, 1.365]). We did not find a significant contribution for other types of temperaments. Better sexual functioning was also associated with a better quality of life. Our findings highlight the importance of temperament traits in sexual functioning in euthymic BD, which may have implications in sexual dysfunction prevention.

Attentional engagement and inhibitory control according to positive and negative symptoms in schizophrenia: An emotional antisaccade task

Despite schizophrenia (SZ) is characterized by a high psychopathological heterogeneity, the underlying psychological mechanisms that result in different clinical profiles are unclear. This study examined the cognitive processing of emotional faces (angry, happy, neutral, and sad) by means of assessing inhibitory control (antisaccade task) and attentional engagement (prosaccade task) with the eye-tracking paradigm. Firstly, two clinical SZ subgroups classified according to the predominance of positive (PSZ; n = 20) or negative symptoms (NSZ; n = 34) and a control group of 32 individuals were compared. Secondly, the association between prosaccade and antisaccade measurements and the severity of positive and negative symptoms were analyzed. The PSZ group showed slower antisaccades when angry faces were displayed, and higher positive symptoms were associated with slower prosaccade latencies to ones. Conversely, the NSZ group made overall slower prosaccades with an emotional advantage for angry faces, and higher negative symptoms were associated with faster antisaccade latencies to ones. Hence, whereas positive SZ profile is related to a lack of attentional engagement and an impaired inhibitory control to threatening information; negative SZ profile is linked to a lack of attentional engagement to faces, mainly with non-threat ones, and with an advantage to ignore distracting threatening stimuli. These findings support affective information-processing theories suggesting a hypersensitivity to threat for positive SZ profiles, and a desensitization to socio-emotional information for negative ones. Consequently, characterizing psychological mechanisms of SZ may allow improving current treatments to threat management when positive symptoms are predominant, or emotion sensitization when negative symptoms prevail.

Attentional biases towards emotional scenes in autism spectrum condition: An eye-tracking study

BACKGROUND

Different attentional processing of emotional information may underlie social impairments in Autism Spectrum Condition (ASC). It has been hypothesized that individuals with ASC show hypersensitivity to threat, which may be related to an avoidance behaviour. However, research on the attentional processing of emotional information in autism is inconclusive.

AIM

To examine the attentional processing biases of 27 children with ASC and 25 typically developed (TD) participants.

METHODS AND PROCEDURES

The initial orienting of attention, the attentional engagement, and the attentional maintenance to complex emotional scenes in competition (happy, neutral, threatening, sad) were assessed in a 20-second eye-tracking based free-viewing task.

OUTCOMES AND RESULTS

i) children with ASC showed an initial orienting bias towards threatening stimuli; ii) TD children demonstrated an attentional engagement and maintenance bias towards threat, while children with ASC did not; and iii) in children with ASC, attentional problems and somatic complaints were associated with higher initial orienting and with higher attentional maintenance towards threat, respectively.

CONCLUSIONS AND IMPLICATIONS

These results suggest that a perceived threat induces an early overwhelming response in autism, giving rise to an avoidance behaviour. The findings endorse affective information processing theories and shed light on the mechanisms underlying social disturbances in ASC.

The effect of concomitant benzodiazepine use on neurocognition in stable, long-term patients with bipolar disorder

OBJECTIVE

Neurocognitive dysfunction is a common feature of bipolar disorder even in euthymia, and psychopharmacological treatment could have an effect on cognition. Long-term prescription of benzodiazepines in bipolar disorder is a common practice, and their effect on neurocognition has not been well studied in this population. The aim of this study was to evaluate the impact of concomitant benzodiazepine long-term use on neurocognitive function in stable euthymic bipolar disorder patients.

METHODS

Seventy-three euthymic bipolar disorder outpatients and 40 healthy individuals were assessed using a neurocognitive battery. Patients were classified in two groups according to the presence of benzodiazepines in their treatment: the benzodiazepine group (n = 34) and the non- benzodiazepine group (n = 39). Neurocognitive performance was compared between the groups using a multivariate analysis of covariance, considering age, number of depressive episodes, adjuvant antipsychotic drugs, Young Mania Rating Scale score and Hamilton Depression Rating Scale score as covariates.

RESULTS

Both bipolar disorder groups (benzodiazepine and non-benzodiazepine) showed an impairment in memory domains (Immediate Visual Memory [p = 0.013], Working Memory [p < 0.001], and Letter-Number Sequence [p < 0.001] from the Wechsler Memory Scale-Revised-III) and slower processing speed functions (Stroop Colour [p < 0.001]) relative to the control group. Nevertheless, the benzodiazepine group showed a greater impairment in executive functions (Conceptual Level Responses [p = 0.024] from the Wisconsin Card Sorting Test and Frontal Assessment Battery [p = 0.042]).

CONCLUSION

Although memory and processing speed impairments were found in bipolar disorder, regardless of their benzodiazepine treatment, benzodiazepine users presented additional neurocognitive impairments in terms of executive functioning. These findings support restricted prescription of benzodiazepines in individuals with bipolar disorder.

Manipulating feedback on schizophrenia: Evidence from a Posner task

Individuals with schizophrenia show difficulties in achieving vital objectives. Abnormal behavioral and emotional responses to environmental feedback may be some of the psychological mechanisms underlying this lack of goal attainment in schizophrenia. The present study aims to assess how different types of feedback may affect performance in a computerized affective Posner task (non-monetary vs. monetary rewards; contingent vs. non-contingent feedback). The sample was composed of 32 patients with schizophrenia and 35 controls. Reaction times and error rates were the behavioral measurements. The emotional experience was assessed through self-reported affective scales. The results indicated that: ii) the performance with monetary rewards was better than with non-monetary ones in all participants, especially in patients with schizophrenia when higher attentional resources are required (invalid trials). Second, all participants demonstrated faster reaction times, but higher error rates, with non-contingent feedback (frustration condition). Significantly, the schizophrenia group only equaled the controls performance in the non-contingent condition with monetary rewards. Additionally, the higher the negative symptoms were in patients, the worse performance they had under frustration. Third, discrepancies between performance and self-report affect were found in patients. Specifically, after the induction of frustration, the patients reported feeling better and having no arousal changes. Therefore, the findings suggest that, in schizophrenia: i) non-monetary rewards are relatively less important; ii) monetary rewards lessen the negative effects of frustration, iii) discrepancies in self-reported affective scales suggest an unrealistic self-evaluation made under frustration. These findings shed light on the underlying mechanisms of the lack of goal attainment in schizophrenia.

An eye-tracking study for measuring the attentional characteristics towards emotional scenes in children with autism spectrum condition

Introduction

The difficulties in social interaction present in individuals with autism spectrum conditions may are related with the abnormal attentional processing of emotional information. Specifically, it has been hypothesized that the hypersensibility to threat shown by individuals with autism may explain an avoidance behaviour. However, this hypothesis is not supported by research and the underlying psychological mechanisms of social interaction in autism still unclear.

Objectives

The aim of the present study was to examine attentional processing biases by administering a computer-based attentional task in a sample of 27 children with autism spectrum conditions and 25 typically developed participants (age 11-15 years).

Methods

The initial orienting of attention, the attention al engagement, and the attentional maintenance to different emotional scenes in competition (i.e. happy, neutral, threatening and sad) were measured by recording the eye movements during a 20 seconds free-viewing task.

Results

The main findings were: i) children with autism spectrum conditions showed an initial orientating bias towards threatening stimuli; and ii) while typically developed children revealed an attentional engagement and attentional maintenance bias towards threatening stimuli, children with autism spectrum conditions did not.

Conclusions

The findings of the present study are consistent with the affective information processing theories and shed light on the underlying mechanisms of social disturbances in autism spectrum conditions.

Impact of maternal age on infants' emotional regulation and psychomotor development

BACKGROUND

Maternal age has progressively increased in industrialized countries. Most studies focus on the consequences of delayed motherhood for women's physical and mental health, but little is known about potential effects on infants' neurodevelopment. This prospective study examines the association between maternal age and offspring neurodevelopment in terms of both psychomotor development (Ages & Stages Questionnaires-3) and emotional competences (Early Childhood Behavior Questionnaire).

METHODS

We evaluated a cohort of healthy pregnant women aged 20-41 years and their offspring, assessed at 38 weeks gestation (n = 131) and 24 months after birth (n = 101). Potential age-related variables were considered (paternal age, education level, parity, social support, maternal cortisol levels, and maternal anxiety and depressive symptoms). Bayesian ordinal regression models were performed for each neurodevelopmental outcome.

RESULTS

Maternal age was negatively associated with poor child development in terms of personal-social skills [odds ratio (OR) -0.13, 95% confidence interval (CI) 0.77-0.99] and with difficult temperament in terms of worse emotional regulation (OR -0.13, 95% CI 0.78-0.96) and lower positive affect (OR 0.16, 95% CI 0.75-0.95). As for age-related variables, whereas maternal anxiety symptoms and cortisol levels were also correlated with poor child development and difficult temperament, maternal social support and parental educational level were associated with better psychomotor and emotional competences.

CONCLUSION

Increasing maternal age may be associated with child temperament difficulties and psychomotor delay in terms of social interaction skills. Early detection of neurodevelopment difficulties in these babies would allow preventive psychosocial interventions to avoid future neuropsychiatric disorders.

Attentional biases to emotional scenes in schizophrenia: An eye-tracking study

Attentional biases to emotional information may play a key role in the onset and course of schizophrenia. The aim of this experiment was to examine the attentional processing of four emotional scenes in competition (happy, neutral, sad, threatening) in 53 patients with schizophrenia and 51 controls. The eye movements were recorded in a 20-seconds free-viewing task. The results were: (i) patients showed increased attention on threatening scenes, compared to controls, in terms of attentional engagement and maintenance; (ii) patients payed less attention to happy scenes than controls, in terms of attentional maintenance; (iii) whereas positive symptoms were associated with a late avoidance of sad scenes, negative symptoms were associated with heightened attention to threat. The findings suggest that a threat-related bias and a lack of sensitivity to positive information may represent an underlying psychological mechanism of schizophrenia. Importantly, schizophrenia symptoms modulated the attentional biases, which has aetiological and therapeutic implications.

Manic espisode, confusional syndrome and reversible splenial lesion after abrupt withdrawal of oxcarbazepine

BACKGROUND

Anticonvulsants are considered a second line option for bipolar disorder, it is known that the abrupt withdrawal is rarely related with demyelinated lesions of the splenium of the corpus callosum. Oxcarbazepine is used in bipolar disorder although it is not stated in the data sheet.

CLINICAL CASE

We presented a case of a 50 years old woman with bipolar disorder who is treated with lithium and oxcarbazepine, she presented a manic episode and a confusional syndrome after she stopped taking the medication. The magnetic resonance showed a restricted diffusion area at the splenium of the corpus callosum and bifrontal hygromas that disappear two weeks later.

CONCLUSIONS

The results of this study suggest that for a patient presenting with a mild encephalopathy and reversible splenial lesion, one should consider whether it is related to withdrawal of oxcarbazepine.

[Renal angiomyolipoma. Ultrasonography and computerized tomography findings]

OBJECTIVE

To analyze the US and CT findings and their value in the diagnosis and follow-up of renal angiomyolipoma.

METHODS/RESULTS

The clinical features, US and CT findings in 17 cases of renal angiomyolipoma were reviewed. Patient mean age was 49.1 years, 15 were asymptomatic and two presented with spontaneous bleeding. Two patients with Bourneville's disease presented bilateral lesions. The presumptive diagnosis was based on the US findings in 15 patients and on the CT findings in 16 patients. The remaining patient was evaluated by MRI. Three patients underwent partial nephrectomy and three other patients required total nephrectomy.

CONCLUSIONS

Ultrasound is useful in the diagnosis of renal angiomyolipoma and it is probably the method of choice for follow-up. Two thirds were echogenic, although an echogenic lesion is not necessarily fat or viceversa. It is therefore necessary to perform a CT evaluation to make the diagnosis, especially if the tumor produces symptoms. In this series, detection of fat on CT evaluation was diagnostic of renal angiomyolipoma, although fatty tissue can also be found in other tumors or inflammatory lesions. Occasionally, the densitometric findings may not be conclusive due to the artefact of partial volume. The use of 5 mm slices without contrast and volumetric acquisitions for reconstruction can enhance the spatial resolution. It must also be taken into account that the fat content of a lesion can be scanty and may be undetected or not distinguished from other tumors.

[Effect of LHRH agonists on testicular microcirculation with Doppler laser flowmetry]

The purpose of this paper is to present the changes that take place in testicular microcirculation measured by DLF during systemic administration of LHRH agonists. The essay includes a comparison with the variations registered in the volume of testicular interstitial fluid, the anatomopathological changes and the associated leucocyte demyeloperoxidase levels. We also examine the relationship between testicular microcirculation changes and plasma testosterone levels. To do this, 50 male Wistar rats were randomly divided into 5 groups, using 10 as control group and the remaining 40 distributed in 4 groups. Measurements were done at 2, 4, 8 and 24 hours after administration of Tryptorelin 0.4 mg i.v. We found that acute administration of an LHRH agonist causes a series of significant changes on testicular microcirculation. Testicular rhythmic microcirculatory flow, i.e., vasomotion, disappears. In turn, accumulation of PMN leucocytes associated to increased venular permeability takes places. Such pre- and postcapillary vascular changes lead to increased vascular permeability which results in increased volume of testicular interstitial fluid. This increased capillary permeability is responsible for the extensive interstitial oedema that would explain the serious histological changes seen on the seminiferous tubule with these drugs.

[Anatomopathologic changes in the testis following prolonged treatment with LHRH agonists. Experimental study in rats]

Presentation of a study conducted on 20 male Wistar rats treated for 3 months with Leuprolide (LHRH agonist). Analysis of pathophysiological testicular changes resulting from the treatment and extent of recovery at 3 months of therapy discontinuation, relating those changes to testosterone plasma levels in peripheral blood. Serum testosterone fell to 1.17 +/- 0.30 ng/ml in the treated group, shifting to figures overlapping with normal values within 3 months of discontinuing treatment. Such decreased testosterone levels translate into significant testicular histological damage. Three months after interruption of treatment there is nearly complete recovery of such damage, with just around 10% tubules without spermatozoa, with unchanged germinal line. We conclude that the marked suppression in testosterone levels caused by LHRH agonists translates into a significant degeneration of the seminiferous tubule, which appears to be reversible 3 months after treatment discontinuation.

[Testicular microcirculation in rats measured with laser-Doppler flowmetry]

Study carried out in 50 male Wistar rats distributed into 5 groups: baseline and at 2, 4, 8 and 24 hours after subcutaneous injection of Human Chorionic Gonadotropin, 100 IU. It was observed that testicular microcirculatory flow shows a rhythmical fluctuating pattern (5-10 fluctuations per minute), which becomes continuous at 4 hours but recovers at 24 hours. At the same time, there is an increased volume of testicular interstitial fluid that peaks at 8 hours, and returns to baseline levels at 24 hours. Serum testosterone values increase with HCG injection, reaching a peak at 4 hours (25.9 mg/ml), to return to nearly baseline levels at 24 hours (5.04 mg/ml). Disappearance of the rhythmical microcirculatory pattern, and the increase of interstitial fluid volume do not appear to be mediated by testosterone, since the raise in hormone levels, occurred after HCG administration, preceded the observed microcirculatory changes.

[Surgical treatment of urinary stress incontinence in women]

Long-term results obtained in 54 surgical procedures to correct effort urinary incontinence performed in 49 patients with this pathology are reviewed. One group was treated with suprapubic urethrovesical suspension with the Marshall-Marchetti-Krantz technique; the other group with endoscopic suspension of the neck of the bladder, with the Stamey technique and the third group with sling techniques. The authors conclude that any of the surgical techniques achieving a correct reposition of urethrovesical anatomy, rising the posterior urethra to its primitive anatomical bed, obtain a similar success rate.

[Percutaneous nephrostomy as a technic for emergency drainage: review of cases]

Percutaneous nephrostomy (PCN) is currently one of the procedures of choice for emergency drainage of the upper urinary tract. Moreover, it permits morphologic and functional diagnostic possibilities as well as a wide variety of new and frequently definitive therapeutic procedures. We report on 58 PCN procedures performed in 55 patients from May 1983 to February 1989. PCN was indicated for complicated or uncomplicated uni- or bilateral supravesical obstruction, with infection and/or azotemia. All patients submitted to PCN for complicated obstruction with infection and/or azotemia showed a marked clinical and analytical improvement. Apart from resolving this emergency, it reduced the morbidity and mortality rate of subsequent surgical treatment of the underlying cause of obstruction because patient status was markedly improved. The major complications, retroperitoneal hematoma and sepsis, were rare. We frequently observed that the catheter had come out or become obstructed in our series. PCN affords the following advantages: it can be performed with local anesthesia; it is a simple technique; there are no absolute contraindications; its morbidity and mortality rates are low; and, it can be easily converted into a permanent procedure. In our view, all the foregoing advantages, as well as its therapeutic and morphologic and functional diagnostic possibilities, make PCN one of the procedures of choice in emergency treatment of upper urinary tract obstruction.

[Calcification and contamination as complications in the use of double-J catheters: incidence and correlation]

We present a series of cases of complex renal lithiasis, in which we carried out temporary internal urinary bypassing, prior to extracorporeal lithotripsy, by means of the retrograde insertion of a double-J urethral catheter, studying the time of stay, the presence or not of contamination in the catheter and its relationship with the calcifications found in them. We also carried out a metabolic-functional study of each patient, determining the urinary pH and the serum and urinary calcium, phosphorous and uric acid concentrations, and observing their possible influence on the above-mentioned complications. Of the 25 catheters studied, we observed calcification in 11 cases (44%). In these we observed urealytic germs (Proteus and Pseudomonas), without finding modifications of urinary pH. We observed no relationship between the calcium deposits and serum and urinary calcium, phosphorous and uric acid concentration.

[Retroperitoneal schwannoma: report of a case]

We report on a patient with a benign retroperitoneal schwannoma whose course had been followed clinically and pathologically for 11 years. The clinical features, diagnosis, prognosis, and treatment of this uncommon tumor type are discussed.

[Kidney pelvis calcification around a double-J ureteral catheter which was impossible to extract. Apropos of a case]

We present a case of pyelorenal calcification on double-J ureteral catheter, which made endoscopic extraction impossible. We review the literature and describe the incidence, methods of diagnosis and treatment of this complication, as well as the means used to avoid it.