Risk factors associated with retinal vein occlusion

AIMS

Retinal vein occlusion (RVO) is the most frequent retinal vascular disease after diabetic retinopathy in which arterial risk factors are much more relevant than venous factors. The objective was to evaluate the role of risk factors in the development of the first episode of RVO.

SUBJECTS AND METHODS

One hundred patients with RVO [mean age 56 years, 42% females and mean body mass index (BMI) 27.5 kg/m(2)] were recruited consecutively from the outpatient clinic of a tertiary hospital in Valencia (Spain). All subjects underwent clinical assessment including anthropometric and blood pressure measurements and laboratory test including homocysteine, antiphospholipid antibodies (aPLAs) and thrombophilia studies. In half of the subjects, a carotid ultrasonography was performed. Three control populations matched by age, sex and BMI from different population-based studies were used to compare the levels and prevalence of arterial risk factors. One cohort of young patients with venous thromboembolic disease was used to compare the venous risk factors.

RESULTS

Blood pressure levels and the prevalence of hypertension were significantly higher in the RVO population when compared with those for the general populations. There was also a large proportion of undiagnosed hypertension within the RVO group. Moreover, carotid evaluation revealed that a large proportion of patients with RVO had evidence of subclinical organ damage. In addition, homocysteine levels and prevalence of aPLAs were similar to the results obtained in our cohort of venous thromboembolic disease.

CONCLUSIONS

The results indicate that hypertension is the key factor in the development of RVO, and that RVO can be the first manifestation of an undiagnosed hypertension. Furthermore, the majority of these patients had evidence of atherosclerotic disease. Among the venous factors, a thrombophilia study does not seem to be useful and only the prevalence of hyperhomocysteinaemia and aPLAs is higher than in the general population.

[Subtelomeric rearrangements in cryptogenic mental retardation]

INTRODUCTION

Mental retardation affects 3% of the population, the origin of which cannot be established in 50% of cases. Subtelomeric rearrangements, not detected by routine cytogenetic studies, might explain some cases of unknown cause.

PATIENTS AND METHODS

A study was conducted on 200 subjects with unexplained mental retardations using multiplex ligation dependent probe amplification (MLPA). Abnormal findings were confirmed by fluorescent in situ hybridization (FISH) and/or comparative genomic hybridization technology (CGH-array).

RESULTS

A subtelomeric aberration was identified in 9 patients. Eight were «de novo»; one was inherited from a phenotypically normal parent. There was a statistically significant association with the presence of more than one dysmorphic feature or with intrauterine growth retardation, but not with the severity of retardation or epilepsy.

CONCLUSIONS

Subtelomeric rearrangements explained 4.5% of cases of mental retardation in our series. The presence of more than one dysmorphic feature or intrauterine uterine growth retardation increases the probability of this type of chromosomal aberration.

Clinical experience with miglustat therapy in pediatric patients with Niemann-Pick disease type C: a case series

Niemann-Pick disease type C (NP-C) is an inherited neurovisceral lysosomal lipid storage disease characterized by progressive neurological deterioration. Different clinical forms have been defined based on patient age at onset: perinatal, early-infantile (EI), late-infantile (Li), juvenile and adult. We evaluated the efficacy and tolerability of miglustat in 16 symptomatic NP-C patients, with comparative reference to one neurologically asymptomatic, untreated patient. All patients were categorized according to age at neurological disease onset, and were assessed using a standardized clinical assessment protocol: disability and cognitive function scales, positron emission tomography (PET), and biochemical markers. PET and disability scale evaluations indicated that cerebral hypometabolism and neurological symptoms were stabilized during treatment in juvenile-onset NP-C patients. EI and Li NP-C patients, who had higher disease severity at baseline (treatment start), showed increased disability scores and progressive cerebral hypometabolism during follow up. Similarly, while cognitive scale scores remained relatively stable in patients with juvenile NP-C, cognition deteriorated in EI and Li patients. Plasma chitotriosidase (ChT) activity was lower in the juvenile NP-C subgroup than in EI and Li patients, and generally increased in patients who discontinued treatment. Plasma CCL18/PARC and ChT activities indicated greater macrophagic activity in EI and Li patients versus juveniles. Miglustat was generally well tolerated; frequent adverse events included diarrhea and flatulence, which were managed effectively by dietary modification and loperamide. Overall, miglustat appeared to stabilize neurological status in juvenile-onset NP-C patients, but therapeutic benefits appeared smaller among younger patients who were at a more advanced stage of disease at baseline.

[Blood neuronal specific enolase in newborns with perinatal asphyxia]

INTRODUCTION

Neuron-specific enolase (NSE) is a sensitive marker of brain injury after hypoxia or ischemia. There are few studies about its usefulness in asphyctic newborns.

OBJECTIVE

To study the correlation between blood NSE levels and neurological outcome in newborns with hypoxic ischemic encephalopathy.

PATIENTS AND METHODS

We have determined the blood values of NSE by radioimmunoassay in 25 asphyctic term-newborns with clinical encephalopathy (of mild, moderate and severe degree) and in 22 healthy term newborns (control group). Blood samples were obtained between 24 and 72 hours after birth in all neonates. Surviving infants were followed for a variable time (median: 3.5 years; range: 1-6) and the neurological status was determined.

RESULTS

NSE levels in the group of asphyctic neonates who died or developed neurological sequelae (n= 6; mean: 116.4 ng/ml; range: 42-226) were significantly higher than NSE values in the group of asphyctic neonates who were neurologically normal at follow-up (n= 19; mean: 21.3 ng/ml; range: 7.4-40), with p< 0.001. There were not differences between NSE values in the group of asphyctic neonates who developed neurologically normal and the control group (mean: 7.6 ng/ml; range: 10.3-28.3). Sensitivity and specificity of blood NSE as predictor of poor outcome were, respectively, 100% and 78%. The combined specificity for blood NSE together with a moderate/severe encephalopathy was 95%.

CONCLUSIONS

The presence of elevated NSE values in blood after perinatal asphyxia can be a sensitive indicator of conspicuous brain damage. The combined information provided by the severity of the encephalopathy together with the blood NSE values have shown a high predictive value for neurological outcome.

[Partial seizures in a newborn with tuberous sclerosis]

Tuberous sclerosis is characterized by the potential for hamartomatous growth in multiple organs. Common manifestations are hypomelanotic spots, facial angiofibromas, subependymal hamartomas, cortical tubers, cardiac rhabdomyomas, retinal hamartomas, and so on. Seizures and mental retardation are frequent. It is an autosomal dominant disease but there is a high percentage of spontaneous mutations. Neonatal diagnosis is exceptional. We report a case of a female term newborn who presented partial motor seizures at the third day of life. Physical examination revealed only a disturbance of cardiac rhythm. Echocardiography showed ventricular intramural rhabdomyomas. Magnetic resonance imaging disclosed periventricular subependymal nodules and cortical tubers. A retinal hamartoma was found in the right eye. At the age of 1 month, hypomelanotic spots were evident on the back skin. The patient had infantile spasms, followed by poorly controlled partial complex seizures together with severe psychomotor retardation. Examination of both parents was normal. We discuss the uncommon diagnosis of tuberous sclerosis during the neonatal period, as well as the exceptional mode of presentation of our patient, with seizures in the early neonatal period, a phenomenon rarely reported in the literature.

[The determination in the blood of the enzyme neuron-specific enolase in children with acute encephalopathies: the prognostic value in neurological sequelae]

OBJECTIVE

The objective of this study was to evaluate if there is a correlation between blood levels of the enzyme neuron-specific enolase in children with non-traumatic acute encephalopathies with severe alterations in consciousness and the neurological sequellae.

PATIENTS AND METHODS

Neuron-specific enolase (EC 4.2.1.11) activity in plasma was measured by radioimmunoassay in 9 children aged 7 months to 5 years, who suffered acute encephalopathy and coma of non-traumatic origin. The etiology was acute viral encephalitis (n = 4), near drowning (n = 2), shock (n = 2) and cardiac arrest (n = 1). Blood samples were obtained between 24 and 72 hours after the onset of encephalopathy. The neurological status was evaluated 18 months after the onset of encephalopathy in the 8 surviving patients (1 patient with brain death criteria died in the acute stage).

RESULTS

Enzyme activities were significantly higher in the children who showed neurological sequelae (median 68.9 ng/ml, range 35.0-95.6, n = 4) than in those who did not present neurological abnormalities (median 15.8 ng/ml, range 9.7-18.7, n = 5), with p < 0.05. No differences were found between the latter and the control group (median 7.7 ng/ml, range 4.1-12.7, n = 10).

CONCLUSIONS

It appears that the presence of elevated neuron-specific enolase in blood is predictive of neurological outcome in children with acute encephalopathies of non-traumatic origin.

[Prognostic value of the electroencephalogram and cerebral CT scan in neonatal hypoxic-ischemic encephalopathy]

This study has evaluated the usefulness of EEG and TC-scan to predict neurological and developmental outcome in 31 full-term newborns sustaining perinatal asphyxia. Both methods have appeared to be valuable early predictors of neurodevelopmental sequelae.

[Meningitis associated with congenital dermal sinus]

Three cases of congenital dermal sinus associated with recurrent meningitis are presented. Severe neurological sequelae were seen in the three patients because diagnosis was done too late. Authors emphasize the necessity of doing in these patients a meticulous visual exploration of the middle line on the skin from occipital to coccyx zones searching some defect in order to perform myelography and to make an early extirpation of the intraspinal tumor and to close congenital dermal defect.