Single-voxel MR spectroscopy and diffusion-weighted MRI in two patients with <Emphasis Type="SmallCaps">l</Emphasis>-2-hydroxyglutaric aciduria

l-2-Hydroxyglutaric aciduria is a rare inherited, neurometabolic disorder. The underlying metabolic defect and the pathophysiology of l-2-hydroxyglutaric aciduria have not yet been defined. We present MR spectroscopy and cranial MR imaging findings, including diffusion-weighted sequences in two male siblings (aged 10 and 12 years). MR spectroscopy revealed a multiplet at 2.10–2.50 ppm and two broad peaks at 0.9–1.6 ppm. The multiplet at 2.10–2.50 ppm might have been created by elevated glutamate and glutamine or l-2-hydroxyglutaric acid itself, which has a similar chemical structure to glutamate. Diffusion-weighted images demonstrated increased diffusion of water molecules in the white-matter lesions.     

Diminished cord blood lymphocytel-selectin expression in neonatal bacterial infection

l-Selectin, a leukocyte surface glycoprotein involved in white blood cell extravasation, is rapidly down-regulated after leukocyte activation. We prospectively determined lymphocytel-selectin expression in freshly obtained cord blood samples of 98 neonates (gestational age 25–42 weeks). In eight infants with bacterial infection, the mean percentage ofl-selectin^high lymphocytes was 32.5% (SD 20.1%), compared to 60.1% (SD 18.7%) in the control group (P<0.01). A percentage ofl-selectin^high lymphocytes of less than 42% had a sensitivity of 75% and a specificity of 82% in identifying infected newborns. Cord blood lymphocytel-selectin expression was independent of gestational age, birth weight, umbilical artery pH, hematocrit, white blood cell count, absolute neutrophil count, C-reactive protein level, or maternal fever before delivery while there was a weak correlation with the newborn's immature/total ratio and platelet count. To our knowledge, this is the first report demonstrating downregulation of human lymphocytel-selectin expression following activation of the immune system in vivo.     

L-2-hydroxyglutaric aciduria: a report of 29 patients

L-2-hydroxyglutaric aciduria (L2HGA) is a chronic slowly progressive neurodegenerative disease characterized mainly by psychomotor developmental delay and cerebellar dysfunction. We report the clinical, biochemical, and neuroimaging features of 29 patients from 22 families. The mean age at the time of diagnosis was 13.4 years (2.5-32 years). The mean follow-up period of patients was four years (1.5-16 years). The main clinical findings were mental retardation and cerebellar involvement with ataxic gait and intentional tremor. Additional findings were mental retardation, macrocephaly and seizures. Diagnosis was confirmed by increased urinary excretion of L-2-hydroxyglutaric acid in all patients and highly specific magnetic resonance imaging (MRI) pattern showing subcortical leukoencephalopathy with bilateral high signal intensity in dentate nuclei and putamens. During the follow-up period, all patients had a static encephalopathy course. The underlying metabolic defect and the possible role of L-2-hydroxyglutaric acid are studied in a subgroup of these families and under evaluation for publication.     

Untersuchungen über die Sekretion des Wachstumshormons nach Gabe von Nacom (l-Dopa und l-Carbidopa)

Zusammenfassung Bei Kindern ohne Minderwuchs im Alter von 6–14 Jahren wurde nach oraler Gabe von 250 mg Levodopa und 25 mg l-Carbidopa (Nacom, ein Kombinations-präparat) die Wachstumshormonkonzentration im Serum bestimmt. Alle Probanden zeigten einen ausreichenden Wachstumshormonanstieg. Der Mittelwert betrug 19,6 ng/ml. Nach dem Maximum der HGH-Konzentration ließen sich zwei Gruppen unterscheiden. Die eine Gruppe erreichte zum Zeitpunkt 20 bzw. 40 min, die andere nach 60 bzw. 90 min den stärksten HGH-Anstieg. Aufgrund des Verlaufs der Mittelwertskurve werden 2 Blutentnahmen, 40 und 90 min nach Einnahme des Präparates, zum Ausschluß eines Wachstumshormonmangels für ausreichend gehalten. Das wahrscheinlich zugrundeliegende Wirkungsprinzip der HGH-Sekretion durch l-Dopa und l-Carbidopa wird anhand der Literatur diskutiert.

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HGH secretion after oral application of l-Dopa and l-Carbiodopa

The stimulatory effect of l-Dopa and l-Carbidopa (Nacom) on HGH secretion was determined in 12 children of normal height aged from 6 to 14 years. Each child received a standard dose of 250 mg l-Dopa and 25 mg l-Carbidopa p.o. HGH concentration in the serum was determined at standard intervals. All subjects showed a sufficient increase of HGH. The mean value was 19.6 ng/ml. According to the maximum values of the HGH concentration the sample can be divided into two groups; the first group reached the highest values after 20–40 min, the second one after 60–90 min. On evaluation of the curve of the mean values it appears that 2 blood samples taken 40 and 90 min after the ingestion of l-Dopa and l-Carbidopa are sufficient in order to exclude HGH deficiency. The theoretical background for HGH secretion after stimulation by l-Dopa and l-Carbidopa is discussed.

Herrn Prof. Dr. U. Köttgen zum 70. Geburtstag.     

Propionylcarnitine excretion is not affected by metronidazole administration to patients with disorders of propionate metabolism

Propionylcarnitine (PC) excretion has been measured during a clinical trial of metronidazole therapy in two patients with propionic acidaemia and two patients with methylmalonic aciduria. All patients were in good metabolic control and were receivingl-carnitine. While total propionate excretion was reduced by up to 40% in all four patients during metronidazole therapy, the excretion of propionylcarnitine remained largely unchanged. PC comprised up to 80% of total propionate excretion in patients with propionic acidaemia.     

Bone mineral density in adolescent females treated withl-thyroxine: a longitudinal study

It has been suggested that chronic treatment withl-thyroxine (l-T4) could be implicated in reducing bone mineral density (BMD). The purpose of this longitudinal study was to determine whether appendicular and axial BMD is decreased byl-T4 treatment in adolescent girls. Thirteen adolescent girls with subclinical hypothyroidism caused by chronic lymphocytic thyroiditis were enrolled in the study at the median age of 13.4 years (range 9.2–18.1 years).l-T4 was administered in a single dose of 1–5 g/kg daily. BMD was evaluated at the distal one-third of the non-dominant radius by single photon absorptiometry (SPA) and at the lumbar spine (L2–4) by dual energy X-ray densitometry (DEXA). Osteocalcin levels were measured to assess bone turnover before and duringl-T4 treatment. Before the start of therapy, mean BMD at both the radial and lumbar level was not significantly different from that of a control group (median age 13.0 years; range 9.0–18.5 years). Duringl-T4 therapy for 2–5 years, BMD did not change at any site. Before treatment, osteocalcin levels were not significantly different from those of controls and did not change during follow up.Conclusion Long-terml-T4 therapy in adolescent girls has no adverse effect on BMD and bone turnover. Our data indicate that attainment of peak bone mass is not impaired byl-T4 administration.     

<Emphasis Type="SmallCaps"> l</Emphasis> -5-Hydroxytryptophan treatment of sleep terrors in children

To test the hypothesis that the administration of l -5-hydroxytryptophan ( l -5-HTP) might exert beneficial effects on sleep terrors, we carried out an open pharmacological trial in a group of children with sleep terrors compared to a group of children with the same disorder but without l -5-HTP treatment. Participants in the trial were 45 children (34 males and 11 females; age range 3.2–10.6 years), referred to the Sleep Centre of the Department of Developmental Neurology and Psychiatry of the University of Rome La Sapienza, affected by sleep terrors. All subjects underwent: (1) complete medical and sleep history; (2) complete neurological examination and EEG recording whilst awake and sleeping, (3) a structured sleep diary for 2 months, (4) after 1 month, all subjects were examined again from the clinical and EEG points of view and (5) after 6 months, a structured interview in order to evaluate the clinical outcome. After the first visit, l -5-HTP was administered (2 mg/kg per day) at bedtime to 31 randomly selected patients for a single period of 20 consecutive days. After 1 month of treatment, 29/31 (93.5%) of patients showed a positive response. In the comparison group without drug therapy, after 1 month, the episodes disappeared only in four children (28.6%) while ten children (71.4%) showed the persistence of episodes with the same frequency as before. After 6 months, 26/31 (83.9%) of children treated with l -5HTP were sleep terror-free, while in five children (16.1%) sleep terror episodes persisted. Of the children in the comparison group, ten (71.4%) continued to show sleep terrors at 6-month follow-up. Conclusion:to our knowledge, this is the first study demonstrating the efficacy of a new drug treatment for sleep terrors. These results confirm our initial hypothesis and represent evidence that treatment with l -5-hydroxytryptophan is able to modulate the arousal level in children and to induce a long-term improvement of sleep terrors.Abbreviations EMS eosinophilia-myalgia syndrome - HSDWA hypersynchronous high voltage delta waves arousal - HVMD high voltage monomorphic delta - l -5-HTP l -5-hydroxytryptophan - NREM non rapid eye movement - PLMs periodic limb movements during sleep - SDB sleep-disordered breathing     

The dentate nucleus in children: normal development and patterns of disease

The dentate nuclei lie deep within the cerebellum and play a vital role in the pathways involved in fine motor control and coordination. They are susceptible to a variety of diseases. Some pathological processes preferentially affect the dentate nuclei, while concomitant basal ganglia or white matter involvement can be a striking finding in others. A familiarity with the normal appearance of the dentate nuclei at different ages in combination with the radiological distribution of pathology in the brain allows the paediatric radiologist to develop a logical approach to the interpretation of MR imaging of these deep cerebellar nuclei. In this article we review the normal appearance and MR features of the dentate nuclei, including changes that are seen with myelination. We describe the specific imaging characteristics of childhood diseases that involve the dentate nuclei, and develop a systematic approach to the differential diagnosis of dentate nucleus abnormalities on MR imaging.     

Magnetic resonance imaging in juvenile Canavan disease

We present a 2-year-old boy and a 6-year-old girl with mild Canavan disease (CD). Aspartoacylase activity in skin fibroblasts was deficient. Magnetic resonance imaging (MRI) of the brain did not show the prominent leucodystrophy previously reported in CD, but there was a hyperintense signal from the lentiform nuclei and the heads of the caudate nuclei on the T2-weighted MR images. This suggests a specific vulnerability of the corpus striatum in these patients. In the older patient, the white matter became affected at the age of 6 years. Proton magnetic resonance spectroscopy (¹H-MRS) of white matter revealed a normal concentration of N-acetyl-l-aspartate (NAA) and a markedly decreased concentration of choline containing compounds (Cho) in the boy but a normal ratio of NAA to Cho in the girl. We conclude that deficient NAA catabolism affects myelin metabolism. This may present as changes in the striatum and/or as a low concentration of Cho before leucodystrophy appears on MRI.     

Osteonecrosis of vertebrae in a child with acute lymphocytic leukaemia duringl-asparaginase therapy

We report a child with acute lymphocytic leukaemia who developed simultaneous osteonecrosis of vertebrae and cerebral thrombosis duringl-asparaginase therapy. Fibrinogen, antithrombin III and plasminogen were decreased. Fresh frozen plasma in addition to antithrombin III concentrates were used to replenish these haemostatic proteins.l-asparaginase induced coagulopathy may cause osteonecrosis.     

Über den Einfluß von Glucose auf den Umsatz von l-Tryptophan beim Säugling

Zusammenfassung Es wird der Einfluß parenteral verabfolgter Glucose auf den Umsatz von l-Tryptophan beim Säugling untersucht. Höhere Glucosedosen rufen eine Verlängerung der biologischen Halbwertzeit hervor bei gleichzeitiger Abnahme des Transfer. Dabei ist die Rate der Elimination von l-Tryptophan von der Höhe der zugeführten Glucosedosis abhängig. Es besteht jedoch weder eine positive noch negative Korrelation zur Höhe des Cortisolspiegels im Plasma. Die für die Änderung der kinetischen Werte in Betracht kommenden Ursachen werden diskutiert.

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The effect of glucose on the turnover of l-tryptophan in infants

The influence of intravenous administered glucose on the turnover of l-tryptophan in infants has been studied. High doses of glucose cause a prolongation of the biological half-life with simultaneous reduction of the transfer. Moreover, the rate of elimination of l-tryptophan is dependent upon the dose of glucose administered. However, there is neither a positive nor a negative correlation with the plasma level of cortisol. The factors which influence the kinetic values are discussed.

Die Ergebnisse sind Teile der Dissertation von Herrn Spangenberg.     

围产期不良事件致新生儿急性缺氧缺血性脑损伤的类型分析

目的 探讨围产期不良事件致新生儿急性缺氧缺血性脑损伤（HIBI）的临床及影像学特征。方法 选取2004~2013 年46 例HIBI 患儿,对其临床及脑损伤类型进行分析。结果 足月儿组脑白质损伤为95%、皮层损伤90%、基底节- 丘脑损伤75% 和脑干损伤65%。早产儿组脑白质损伤73%、皮层损伤23%、基底节- 丘脑损伤19%、脑干损伤15%。早产儿灰质损伤发生率均低于足月儿组（P<0.05）;46% 的急性HIBI患儿伴有多器官功能受累,足月儿组临床表现较典型,95% 符合中、重度脑病,影像学改变多为混合型损伤,且以中、重度基底节- 丘脑损伤为主（68%）。多器官受累及动脉血pH 值小于7.1 与中、重度脑损伤的发生密切相关。结论 白质损伤是最常见的HIBI 类型,早产儿组也可见灰质损伤,但发生率低。中、重度脑病患儿的影像学损伤程度较重,且以基底节- 丘脑损伤为主。多器官受累、异常神经系统表现及早期血气分析对新生儿HIBI 诊断尤为重要。     

新生儿缺氧缺血性脑病磁共振诊断与损伤类型的分类建议

新生儿缺氧缺血性脑病(HIE)有比较统一的临床诊断与分度标准,但是符合相同诊断标准的窒息所致HIE的临床表现、神经病理损伤类型有很大差异。磁共振成像(MRI)能很好地呈现HIE损伤类型、损伤进程,且与其远期神经发育结局密切相关,但不同MRI检查序列所反映的损伤表现可能不尽相同。弥散加权序列适宜的检查时间为出生后2~4 d,常规序列为出生后的4~8 d。HIE的MRI主要损伤类型有丘脑基底节+内囊后肢损伤、分水岭样损伤累及皮层和皮层下白质、局灶-多灶性微小性白质损伤,以及广泛全脑性损伤。严重的急性产时窒息易导致深部灰质损伤(丘脑基底节),也可累及脑干,锥体束是最易受累的白质纤维束,而反复间断性缺氧缺血以及伴有感染、低血糖等易导致分水岭区和深部白质损伤。但上述损伤类型有时很难明确区分,而是以某一类型为主,并非所有HIE都有特征性的MRI表现。     

Tissue damage in rat ovaries subjected to torsion and detorsion: effects of <Emphasis Type="SmallCaps">l</Emphasis>-carnitine and <Emphasis Type="Italic">N</Emphasis>-acetyl cysteine

We aimed to evaluate histopathological changes, to detect HIF-1α staining intensities and to determine MDA levels in rat ovaries, which were subjected to torsion and detorsion and treated with l-carnitine or N-acetyl cysteine (NAC). Forty-eight prepubertal female Sprague–Dawley rats were divided into five groups (n = 8): 1, control; 2, ischemia; 3, reperfusion; 4, l-carnitine; and 5, NAC groups. In groups 3, 4 and 5, an ischemic period of 3 h was followed by reperfusion for 24 h. In groups 4 and 5, ischemia was performed and either l-carnitine or NAC was infused intraperitoneally 30 min before reperfusion. Ovarian tissues were examined histopathologically; tissue MDA levels and serum IL-6 levels were determined biochemically. HIF-1α was applied to all ovaries immunohistochemically. Total tissue damage scores, tissue MDA levels and HIF-1α scores, were significantly higher in group 2 (all P < 0.001) than group 4, and group 3 than group 4 (P < 0.001, P = 0.05 and P < 0.001, respectively). They were also significantly higher in group 2 (all P < 0.001) than group 5. When group 3 is compared to group 5, total tissue damage scores and tissue MDA levels were significantly higher in the former (P < 0.01 and P < 0.001, respectively). Serum IL-6 levels were significantly higher in group 2 when compared to groups 1, 4 and 5 (all P < 0.01). The degree of tissue damage of the torsioned ovaries decreased after a reperfusion period of 24 h in the torsioned ovaries. However, ovaries of both l-carnitine and NAC groups showed better recovery than the reperfusion group. This study was accepted for poster presentation in the 21st European Congress of Pathology, held in Istanbul, Turkey, on 8–13 September 2007.     

A patient with infantile spasms and low homovanillic acid levels in cerebrospinal fluid: l-dopa dependent seizures?

We report a 3-month-old female with infantile spasms that responded transiently to pyridoxine and permanently to oral l-dopa. Initial CSF levels of homovanillic acid were low, suggesting disturbed turnover of dopamine. These findings suggest that disturbed brain monoamine metabolism may be causally related to infantile spasms.Abbreviations CSF cerebrospinal fluid - HVA homovanillic acid - 5-HIAA 5-hydroxyindoleacetic acid This report is dedicated to Professor Yukio Fukuyama on the occasion of the 20-year anniversary of his chairmanship at the Department of Paediatrics, Tokyo Women's Medical College     

弥散加权成像早期预测新生儿缺氧缺血性脑损伤区域及其表观弥散系数值改变

目的 阐明弥散加权成像(diffusion weighted imaging,DWI)可于生后早期预测HIE患儿的损伤区域,并且评估不同区域的ADC值变化情况.方法 研究对象为2006年7月至2009年7月,我院新生儿病房收治26例HIE患儿,其临床分度为重度19例和中度7例,均于生后72 h内完成常规MRI和DWI扫描.其中,10例重度HIE患儿(ADC值组)行8个感兴趣区的ADC值测量,以同期住院的12例无神经系统疾病的足月儿为对照.8个感兴趣区分别为内囊后肢(PLIC)、腹外侧丘脑、基底节、中央沟周围皮层、枕叶皮层、半卵圆中心、脑干、额叶白质.结果 生后72 h内,26例HIE患儿的常规MRI示5例蛛网膜下腔出血、2例硬膜下出血,仅1例患儿的T2WI可见部分皮层稍高信号,此外未见其他异常.但26例HIE患儿的DWI均可见异常高信号.在19例重度HIE患儿中,17例(89%)表现为双侧腹外侧丘脑和中央沟周围皮层的异常高信号(其中6例伴有双侧基底节区异常高信号),仅2例(11%)表现为皮层及皮层下白质的异常高信号.7例中度HIE中,4例表现为皮层及皮层下自质的异常高信号,2例表现为脑室周围白质的异常高信号,仅1例表现为双侧腹外侧丘脑和中央沟周围皮层的异常高信号.ADC值组内囊后肢(PLIC)、腹外侧丘脑、基底节、中央沟周围皮层、枕叶皮层、半卵圆中心、脑干、额叶白质的平均ADC值依次为0.68(0.56～0.88),0.73±0.13,0.67±0.11,0.78±0.22,0.90±0.16,0.87±0.21,0.73±0.19,1.32±0.22×10-3 mm2/S.对照组内囊后肢(PLIC)、腹外侧丘脑、基底节、中央沟周围皮层、枕叶皮层、半卵圆中心、脑干、额叶白质的平均ADC值依次为0.96(0.95～1.02),1.02±0.90,1.15±0.99,1.08±0.07,1.09±0.08,1.39±0.20,0.96±0.05,1.58±0.18×10-3 mm2/S.与对照组相比,ADC值组8个感兴趣区的平均表观弥散系数(apparent difusion coefficient,ADC)值明显降低(P＜0.01).结论 在生后早期,重度HIE患儿的损伤区域大部分为丘脑-中央沟周围皮层,仅少数为皮层及皮层下白质.中度HIE患儿的损伤区域较多样,依次为皮层及皮层下白质、脑室周围白质和丘脑-中央沟周围皮层.HIE患儿的DWI图像异常部位及未见异常部位的ADC值均有不同程度的下降.

Abstract：

Objective To elucidate that diffusion weighted imaging (DWI) can be used to predict the injured regions of neonatal brain with hypoxic-ischemic encephalopathy (HIE) in the early phase of injury, and to measure the apparent diffusion coefficient (ADC) values in the multiple regions of the brain.Method The participants in this study were twenty-six infants with HIE from neonatology ward hospitalized between July 2006 and July 2009.Nineteen patients had severe HIE, and seven had moderate HIE.DWI and conventional magnetic resonance imaging (MRI) were performed for each case within the first 72 hrs.The ADC values of eight regions of interest (ROIs) were measured in ten cases with severe HIE ( ADC values group). ROIs included posterior limb of internal capsule (PLIC), ventrolateral thalami, basal ganglia, perirolandic cortex, occipital cortex, centrum semiovale, brainstem, and frontal white matter.Twelve neonates were enrolled as the control subjects.Results During the first 72 hfs, the conventional MR1 of 26 patients showed subarachnoid hemorrhage in 5, subdural hemorrhage in 2, and mild high signal intensity in the cortex of only one patient.In the 19 cases with severe HIE, abnormal signal intensities were seen in ventrolateral thalami and perirolandie cortex of 17 patients ( 89% ), and the remaining 2 infants showed abnormal cortex and subcortical white matter.In 7 cases with moderate HIE, 4 had abnormal signal intensity in the cortex and subcortical white matter, 2 had abnormal periventricular white matter, and only one showed abnormal signal intensity in the ventrolateral thalami and perirolandic cortex.In the ADC values group, the average ADC values of posterior limb of internal capsule ( PLIC ), ventrolateral thalami, basal ganglia, perirolandic cortex, occipital cortex, centrum semiovale, brainstem, and frontal white matterrespectively were 0.68(0.56-0.88) ,0.73 ±0.13,0.67 ±0.11,0.78 ±0.22,0.90 ±0.16,0.87 ±0.21,0.73 ±0.19,1.32 ±0.22 × 10-3 mm2/S.In the control group, the average ADC values of posterior limb of internal capsule ( PLIC ), ventrolateral thalami, basal ganglia, perirolandic cortex, occipital cortex, centrum semiovale, brainstem, and frontal white matter respectively were 0.96(0.95-1.02), 1.02 ±0.90,1.15 ±0.99,1.08 ±0.07,1.09 ±0.08,1.39 ±0.20,0.96 ±0.05,1.58 ±0.18 × 10 -3 mm2/S. There was statistically significant difference in the average ADC values between each of 8 ROIs of infants with HIE and healthy neonates( P ＜ 0.01 ).Conclusion In the first days after birth, the major injured regions of severe HIE were ventrolateral thalami and perirolandic cortex, the minor injured regions were cortex and subcortical white matter.Multiple regions of moderate HIE were injured, including cortex with subcortical white matter,periventricular white matter, and ventrolateral thalami with perirolandic cortex. The ADC values of the regions with abnormal signal intensity decreased, also some regions with the normal signal intensity.     

L-2-hydroxyglutaric aciduria -- a rare cause of macrocephaly

We report on a 9-year-old girl who was referred to our department because of increasing macrocephaly and school problems. The neurological examination disclosed mild cerebellar dysfunction and positive pyramidal tract signs. An MRI of the brain revealed extensive signal alterations of the white matter. Biochemical investigations established the diagnosis of L-2-hydroxyglutaric aciduria which has to be kept in mind as a rare cause of macrocephaly.     

Neuroimaging findings in glutaric aciduria type 1

Objective To review the imaging features of glutaric aciduria type 1 (GA-1) in a group of 20 patients, the largest published series to date. To document the findings not previously reported and compare our findings with the imaging characteristics of GA-1 previously reported in the literature.Materials and methods For 14 patients the original scans were examined and in the remaining 6, where the imaging was unavailable, the radiology reports were consulted. Nine patients had serial cranial US examinations, 13 had 18 CT scans performed and 14 patients had 39 MRI scans.Results Widening of the sylvian fissures and of the fluid spaces anterior to the temporal lobes was seen in 93% of cases. The mesencephalic cistern was also widened in 86%. Abnormal high-signal intensity on T2-weighted (T2-W) images was seen in the basal ganglia and periventricular white matter in 64% of children. Subdural collections were found in 3 patients, all of which resolved spontaneously. Four neonates followed with serial cranial US showed bilateral multiple caudothalamic cysts. Abnormal high signal on T2-W images was seen in the dentate nucleus, substantia nigra and the pontine medial lemniscus in 79, 43 and 64%, respectively.Conclusions Widening of the sylvian fissure, mesencephalic cistern and expansion of CSF spaces anterior to the temporal lobes are cardinal signs of GA-1. If combined with abnormalities of the basal ganglia and white matter, GA-1 should be strongly suspected.Presented at 37th Annual Congress of ESPR, Lisbon, Portugal, May 2000     

α-l-Iduronidase activity in leukocytes: Diagnosis of homozygotes and heterozygotes of the Hurler syndrome

The activity of -l-iduronidase was determined in leukocytes from two patients with the Hurler syndrome, five obligatory heterozygotes, one patient with the Hunter syndrome, and ten normal individuals. It was found that the determination of -l-iduronidase in leukocytes was a useful method for differential diagnosis between the Hurler and Hunter syndromes. Heterozygotes of the Hurler syndrome showed approximately 50% level of -l-iduronidase activity in leukocytes as compared with that of normal individuals.This suggests that the determination of -l-iduronidase activity may be available for the carrier detection of the Hurler syndrome.     

Cranial CT and MRI in malignant phenylketonuria

Malignant phenylketonuria is a rare disease caused by a deficiency in dihydropteridine-reductase which induce a hyperphenylalaninemia and a deficiency of neurotransmitters such as 3,4,dihydroxyphenylalanine (DOPA) and 5 hydroxytriptophan. The case of a patient with malignant phenylketonuria (PKU) who underwent both CT and MR Imaging is reported. CT demonstrated the characteristic calcifications of the basal ganglia. MRI demonstrated areas of hypersignal on T1 images in the basal ganglia, subcortical frontal and occipital white matter and cortex probably corresponding to calcifications. The MR findings are not specific but could be useful in monitoring the diet and neurotransmitter substitution therapy.