The FBN1 (R2726W) mutation is not fully penetrant

The R2726W mutation in the fibrillin 1 (FBN1, Marfan syndrome) gene segregates with isolated skeletal features of Marfan syndrome and/or high stature. Here we report a family in which two out of four individuals, an 18-year-old son and his mother, a 41-year-old woman, had the R2726W mutation of FBN1. Both family members carrying the mutation were of average height. The son had a Marfan-like phenotype, but his mother did not. The FBN1 R2776W mutation, which is associated with skeletal features of Marfan syndrome, appears incompletely penetrant. Consequently, genetic counselling in the presence of this mutation is difficult.

Operative results without invasive monitoring in patients with frontal lobe epileptogenic lesions

PURPOSE

To further explore the still controversial issues regarding whether all or most candidates for epilepsy surgery should be investigated preoperatively with invasive long-term video-EEG monitoring techniques (ILTVE).

METHODS

We studied five patients with intractable seizures since early childhood using the same protocol: clinical evaluation, magnetic resonance imaging (MRI) with fluid-attenuated inversion recovery (FLAIR) sequences, long-term video-EEG (LTVE) monitoring with scalp electroencephalogram (EEG), interictal single photon emission computed tomography (SPECT), positron emission tomography (PET), and neuropsychological testing. The patients' seizures had clinical features suggesting a frontal lobe (FL) origin. MRI scans revealed focal cortical dysplasia (CD) in four patients and a probable gliotic lesion in the fifth. The findings in both PET and SPECT images were congruent with those of the MRI. Scalp LTVE failed to localize the ictal onset, although the data exhibited features suggestive of both CDs and FL seizures. On the basis of these results, surgery was performed with intraoperative corticography, and the cortical area exhibiting the greatest degree of spiking was ablated.

RESULTS

Histopathologic study of four of the resected specimens confirmed the presence of CD, whereas in the fifth, there were features consistent with a remote encephaloclastic lesion. There were no postoperative deficits. Seizures in three of the patients were completely controlled at 2-3.5 years of follow-up; a fourth patient is still having a few seizures, which have required reinstitution of pharmacotherapy, and the fifth has obtained > or =70% control. All patients have had significant improvement in psychosocial measures. For comparison, five patients with generally similar clinical and neuroradiologic features to the previous group underwent preoperative ILTVE monitoring. The surgical outcomes between the two groups have not differed significantly.

CONCLUSIONS

We conclude that patients with FL epilepsies may be able to undergo successful surgery without preoperative ILTVE monitoring, provided there is high concordance between neuroimaging tests (MRI, SPECT, PET) and the seizure phenotypes, even when routine EEGs and scalp LVTE fail to localize ictal onset unambiguously. The surgical outcomes of these patients generally paralleled those of the other subjects who also had FL epilepsy but who were operated on only after standard ILTVE monitoring.

Homocystinuria with transverse sinus thrombosis

A case of cerebral venous thrombosis caused by undiagnosed homocystinuria is reported. The pitfalls regarding the diagnosis of a potentially medically treatable condition are discussed. Cerebral venous thrombosis in children has a variable type of onset and a multiplicity of causes. This type of pathology, although not frequent, is more common than previously thought. Among the different etiologies, undiagnosed homocystinuria is not routinely considered. We report a case of venous thrombosis of the left transverse cerebral sinus in a girl with drug-resistant partial epilepsy and homocystinuria. This diagnosis was considered and confirmed after the appearance of acute cerebral symptoms caused by venous thrombosis.

Clinical and EEG findings in 18 cases of late infantile neuronal ceroid lipofuscinosis

The objective of this study was to present clinical and electroencephalographic findings in 18 cases with late infantile neuronal ceroid lipofuscinoses, focusing on features that assist early diagnosis. Clinical and EEG findings have been described in the past for classic types, but several variants have recently been reported. The authors reviewed the clinical and EEG findings of 18 childhood onset neuronal ceroid lipofuscinoses cases. In the late infantile neuronal ceroid lipofuscinoses type, both typical and variant cases have been observed. In this type, the presence of a particular pseudoperiodic EEG pattern that we found in 15/18 patients and observed in the first stages of the disease could be useful in early diagnosis, especially if associated with the absence of sleep spindles. A precise nosological classification, based both on clinical and instrumental findings is the prerequisite for a correct genotype-phenotype correlation that could greatly improve our knowledge of this disease, providing a better understanding of pathogenesis and increasing our ability to treat it.

Neuronal ceroid lipofuscinoses: clinical and EEG findings in a large study of Italian cases

We reviewed the clinical and EEG features of 30 Italian patients with childhood-onset neuronal ceroid lipofuscinosis (NCL). The outcome and the EEG pattern of the 4 infantile NCL cases were classic, although the age at onset of symptoms varied from 1.0 to 3.5 years. This latter finding is unusual and has not been reported for other Italian patients. Both typical and variant cases of late-infantile NCL (LINCL) were observed. This NCL type represents the most common form in our country, and was the largest group (18 cases) in our study. A particular pseudoperiodic EEG pattern was observed in 15 of the 18 patients with LINCL. This pattern may be useful in early diagnosis, especially if associated with the absence of sleep spindles. In the 8 cases with juvenile NCL, clinical and EEG findings were similar to those reported in the literature.

The syndrome of inv dup (15): clinical, electroencephalographic, and imaging findings

The clinical and laboratory data of four pediatric patients and one adult patient with inverted duplication (inv dup) (15) are reported. The most evident findings were dysmorphic features with frontal bossing; genital abnormalities, such as macropenis or hypospadias; mental retardation; autistic behavior; and seizures. Two additional adults with inv dup (15) from other institutions were also diagnosed in our laboratory. Seizures and mental retardation were the reasons for their referral. The clinical picture of inv dup (15) seems to be quite variable since the phenotype can also be normal. However, karyotyping and fluorescent in-situ hybridization, focused in particular on chromosome 15, appear to be indicated in patients with dysmorphic phenotypes, such as the one present in our patients, and in subjects with early-onset seizures and psychomotor retardation with autistic features.

An unbalanced submicroscopic translocation t(8;16)(q24.3;p13.3)pat associated with tuberous sclerosis complex, adult polycystic kidney disease, and hypomelanosis of Ito

We report on a familial submicroscopic translocation involving chromosomes 8 and 16. The proband of the family had a clinical picture suggestive of a large deletion in the chromosome 16p13.3 area, as he was affected with tuberous sclerosis complex (TSC) and had alpha thalassaemia trait, and his half brother, who also had TSC, may have suffered additionally from polycystic kidney disease (PKD). FISH studies provided evidence for a familial translocation t(8;16)(q24.3;p13.3) with an unbalanced form in the proband and a balanced form in the father and in a paternal aunt. The unbalanced translocation caused the index patient to be deleted for the chromosome 16p13.3-pter region, with the most proximal breakpoint described to date for terminal 16p deletions. In addition, FISH analysis showed a duplication for the distal 8q region. Since the index patient also had hypomelanosis of Ito (HI), either of the chromosomal areas involved in the translocation may be a candidate region for an HI determining gene. Furthermore, it is noteworthy that both carriers of the balanced translocation showed a nodular goitre, while the proband has hypothyroidism.

Lamotrigine in typical absence epilepsy

Lamotrigine (LTG) is an anti-epileptic drug effective in partial seizures and generalized epilepsy. There is growing evidence of the usefulness of LTG in childhood (CAE) orjuvenile (JAE) absences resistant to previous treatment. In this study all patients were identified using strict diagnostic criteria and subdivided into two groups. (1) Eight patients affected by absence seizures resistant to valproic acid or ethosuximide, received LTG as an-add-on therapy, (2) seven patients affected by typical absence seizures not previously treated, received LTG monotherapy after the diagnosis. In the patients with resistant absence seizures, a full control of seizures was obtained. In five of them, after a mean period of 12.5 months, the previous anti-epileptic drugs were withdrawn leaving the patients on LTG monotherapy. In one patient, absences relapsed and valproic acid was therefore added again to LTG to regain control of the seizures. In six of the seven patients on LTG monotherapy after the diagnosis, a full control of seizures was obtained. In the seventh patient the drug was stopped due to a skin rash. In conclusion LTG appears to be effective in resistant absence seizures in combination with valproic acid. Moreover, our preliminary data suggest that lamotrigine might be used as monotherapy in typical absence seizures. The advantages and disadvantages of LTG monotherapy in this type of epilepsy are discussed.

Diagnosis of Angelman syndrome: clinical and EEG criteria

In order to evaluate which diagnostic criteria can be indicative for an early diagnosis of Angelman syndrome (AS), 144 children with severe epilepsy and mental retardation were evaluated. In 10 of them the diagnostic criteria indicated by Williams were present. Of the remaining 134 patients we were able to diagnose one 15-year-old patient with AS, on the basis of the EEG findings, even though the typical clinical features of the syndrome were absent. In all patients the diagnosis of AS was confirmed by fluorescent in situ hybridization (FISH) in 10 patients and by methylation analysis in one patient. AS is very likely when both typical clinical and EEG findings are present. Nevertheless, it must be considered in all patients affected by severe epilepsy and mental retardation, when the EEG pattern is sufficiently indicative, and FISH and/or molecular analysis should be performed even in absence of typical clinical signs.

High rate of mosaicism in tuberous sclerosis complex

Six families with mosaicism are identified in a series of 62 unrelated families with a mutation in one of the two tuberous sclerosis complex (TSC) genes, TSC1 or TSC2. In five families, somatic mosaicism was present in a mildly affected parent of an index patient. In one family with clinically unaffected parents, gonadal mosaicism was detected after TSC was found in three children. The detection of mosaicism has consequences for genetic counseling of the families involved, as changed risks apply to individuals with mosaicism, both siblings and parents. Clinical investigation of parents of patients with seemingly sporadic mutations is essential to determine their residual chance of gonadal and/or somatic mosaicism, unless a mosaic pattern is detected in the index patient, proving a de novo event. In our data set, the exclusion of signs of TSC in the parents of a patient with TSC reduced the chance of one of the parents to be a (mosaic) mutation carrier from 10% to 2%. In the five families with somatic mosaicism, the parent was given the diagnosis after the diagnosis was made in the child.

Italian multicentre open trial on DDAVP spray in nocturnal enuresis

OBJECTIVE

The aim of the study was to compare the efficacy and safety of different doses of DDAVP spray treatment (20 to 40 mcg/day) in patients with primary monosymptomatic nocturnal enuresis (defined as three or more wet nights per week).

MATERIAL AND METHODS

237 patients (152 males, 75 females; age range 5-17 years), with no infections or organic abnormalities of the urinary apparatus and no neurological disorders, were admitted into the trial. The experimental design was planned as an "open study" with five different treatments schedules (5 groups). The daily doses of DDAVP at bedtime in groups 1 and 2 were 20 and 30 mcg, respectively, for 6 weeks. In groups 3 and 4 the daily doses for the first 2 weeks were 20 and 30 mcg, respectively, and then, after a washout period of 2 weeks, the daily doses for the two groups were 30 and 20 mcg, respectively. A dose-response study (20 to 40 mcg/day) was carried out in group 5.

RESULTS

DDAVP spray therapy in primary monosymptomatic nocturnal enuresis was found to be resolutive in 70-75% of treated patients. No difference in response was found between the patients treated with the daily dose of 20 and those on 30 mcg. No important reactions were observed in patients treated with DDAVP spray at the different daily dose (20 to 40 mcg) or for different periods of time (up to 6 weeks).

CONCLUSIONS

DDAVP spray therapy at a dose of 20 mcg/day was effective in 70-75% of primary monosymptomatic nocturnal enuretics. In non-responders the daily dose of DDAVP should be increased to 30 to 40 mcg.

Microbiological diagnosis of tuberculosis: a comparison of old and new methods

The aim of our study was to evaluate the diagnostic value of various methods widely used in microbiological diagnosis of tuberculosis: direct smear examination for acid-fast bacilli, cultural identification in Lowestein-Jensen (L-J) medium, the radiometric BACTEC 460 system, and Polymerase Chain Reaction (PCR). Three hundred and ninety-three clinical samples of sputum (375), gastric aspirate (3), pleural fluid (12) and urine (3) were taken from 125 patients hospitalized at our Institute for suspected pulmonary tuberculosis, between January 1995 and June 1997. On completion of diagnosis, 35 were found to be affected by active tuberculosis (30 pulmonary, 4 pleural and 1 urinary) and 90 by other non-tubercular diseases (pneumonia, lung cancer, non-tubercular pleural effusion, etc.). In our study, direct smear examination for acid-smear bacilli gave diagnostic value results of 88% and positive predictive value of 91.67%. Cultural identification in L-J and BACTEC 460 TB radiometric system media resulted in diagnostic values of 96.80% and 94.40%, respectively, and positive predictive values of 100% for both of them. Finally, One-Tube Nested-PCR, a variant which uses specific primers for the IS6110 insertion sequence specific for Mycobacterium tuberculosis, gave us 88.80% (91.43% sensitivity and 87.78% specificity) diagnostic value results, and 74.42% (11 false-positives) positive predictive value. On the basis of our results, we can affirm that PCR is a good method for microbiological diagnosis of tuberculosis, given its high sensitivity and specificity and unparalleled rapidity. However, the high number of false-positives that we found suggests that results obtained should be confirmed with BACTEC, which considerably reduces the time required for identification, and makes it possible to carry out an antibiotic assay rapidly.

Lamotrigine treatment in childhood drug resistant epilepsy

The clinical response to lamotrigine has been evaluated in a group of 63 drug resistant epileptic children in an open add-on trial. A negative response was observed in 30 subjects. In 11 patients, after an initial improvement lasting a mean period of 8 months, seizures recurred with the same frequency present before the beginning of the treatment. Twenty-two patients responded to lamotrigine treatment. Period of observation in the responsive group ranged from 1 year to 3 years. Response was complete in 16 patients and in the other 6 a 50% to 90% decrease of seizures was obtained. A complete normalization of the electroencephalogram (EEG) was registered in 10 cases after a mean period of 5 months of therapy. Side effects were mild and limited to 12 patients. Improvement was obtained in social and academic performance. Writing ability improved in one case. Lamotrigine can be considered a useful drug in the therapeutic armamentarium for childhood drug resistant epilepsy.

Novel and recurrent tyrosine aminotransferase gene mutations in tyrosinemia type II

Tyrosinemia type II (Richner-Hanhart syndrome, RHS) is a disorder of autosomal recessive inheritance characterized by keratitis, palmoplantar hyperkeratosis, mental retardation, and elevated blood tyrosine levels. The disease results from deficiency in hepatic tyrosine aminotransferase (TAT). We have previously described one deletion and six different point mutations in four RHS patients. We have now analyzed the TAT genes in a further seven unrelated RHS families from Italy, France, the United Kingdom, and the United States. We have established PCR conditions for the amplification of all twelve TAT exons and have screened the products for mutations by direct sequence analysis or by first performing single-strand conformation polymorphism analysis. We have thus identified the presumably pathological mutations in eight RHS alleles, including two nonsense mutations (R57X, E411X) and four amino acid substitutions (R119W, L201R, R433Q, R433W). Only the R57X mutation, which was found in one Scottish and two Italian families, has been previously reported in another Italian family. Haplotype analysis indicates that this mutation, which involves a CpG dinucleotide hot spot, has a common origin in the three Italian families but arose independently in the Scottish family. Two polymorphisms have also been detected, viz., a protein polymorphism, P15S, and a silent substitution S103S (TCG-->TCA). Expression of R433Q and R433W demonstrate reduced activity of the mutant proteins. In all, twelve different TAT gene mutations have now been identified in tyrosinemia type II.

Inter- and intrachromosomal rearrangements are both involved in the origin of 15q11-q13 deletions in Prader-Willi syndrome

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Celiac disease with cerebral calcium and silica deposits: x-ray spectroscopic findings, an autopsy study

An increased incidence of seizures and cerebral calcifications, usually bilateral and located in the occipital cortex, has been reported in celiac patients. The histology of cerebral lesions is not well defined, and their pathogenesis is only speculative. We report the autopsy results of a patient with celiac disease, seizures, and cerebral calcifications who died following a cerebral hemorrhage caused by Fisher-Evans syndrome. Calcifications were restricted to the cortical gray matter and composed of aggregates of small calcified spicules. Calcium deposition was present as psammoma-like bodies, along small vessels, and within neurons. X-ray spectroscopy of the calcified areas revealed that calcium (43%) and silica (57%) were present in the lesions. High silica content was also found in the cerebral hemorrhagic fluid. Silica toxicity has to be considered in regard to the pathogenesis of the cerebral lesions and of the seizures.

EEG, PET, SPET and MRI in intractable childhood epilepsies: possible surgical correlations

Magnetic resonance imaging (MRI), single photon emission tomography (SPET), and positron emission tomography (PET) using [18F]fluorodeoxyglucose were used in combination with scalp and scalp-video EEGs in a group of 30 pediatric patients with drug resistant epilepsy (DRE) in order to identify patients who could benefit from neurosurgical approach. Seizures were classified according to the consensus criteria of The International League Against Epilepsy. In three patients infantile spasms (IS) were diagnosed; 13 subjects were affected by different types of generalized seizures, associated with complex partial seizures (CPS) in three. In the other 14 patients partial seizures, either simple (SPS) or complex, were present. A localized abnormality was demonstrated in one patient with IS and in three patients with generalized seizures. Of the group of 14 subjects with CPS, MRI and CT were normal in 7, but SPET or PET indicated focal hypoperfusion or hypometabolism concordant with the localization of the EEG abnormalities. In 5 of the other 7 patients anatomical and functional imaging and EEG findings were concordant for a localized abnormality. It can be concluded that functional imaging combined with scalp EEGs appears to be superior to the use of only CT and MRI for selecting children with epilepsy in whom a surgical approach can be considered, in particular when CPS resistant to therapy are present.