[18F]-Fluorodeoxyglucose positron emission tomography in children with neurofibromatosis type 1 and plexiform neurofibromas: correlation with malignant transformation.

The objective of this study was to investigate the predictive value of [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) in detecting malignant transformation of plexiform neurofibromas in children with neurofibromatosis type 1 (NF1). An electronic search of the medical records was performed to determine patients with NF1 who had undergone FDG-PET for plexiform neurofibroma between 2000 and 2011. All clinical, radiologic, pathology information and operative reports were reviewed. Relationship between histologic diagnosis, radiologic features and FDG-PET maximum standardized uptake value (SUV(max)) was evaluated. This study was approved by the Institutional Review Board of our institution. 1,450 individual patients were evaluated in our Multidisciplinary Neurofibromatosis Program, of whom 35 patients underwent FDG-PET for suspected MPNST based on change or progression of clinical symptoms, or MRI findings suggesting increased tumor size. Twenty patients had concurrent pathologic specimens from biopsy/excision of 27 distinct lesions (mean age 14.9 years). Pathologic interpretation of these specimens revealed plexiform and atypical plexiform neurofibromas (n = 8 each), low grade MPNST (n = 2), intermediate grade MPNST (n = 4), high grade MPNST (n = 2), GIST (n = 1) and non-ossifying fibroma (n = 1). SUV(max) of plexiform neurofibromas (including typical and atypical) was significantly different from MPNST (2.49 (SD = 1.50) vs. 7.63 (SD = 2.96), p < 0.001). A cutoff SUV(max) value of 4.0 had high sensitivity and specificity of 1.0 and 0.94 to distinguish between PN and MPNST. FDG-PET can be helpful in predicting malignant transformation in children with plexiform neurofibromas and determining the need for biopsy and/or surgical resection.

22q13.3 deletion syndrome: clinical and molecular analysis using array CGH.

The 22q13.3 deletion syndrome results from loss of terminal segments of varying sizes at 22qter. Few genotype-phenotype correlations have been found but all patients have mental retardation and severe delay, or absence of, expressive speech. We carried out clinical and molecular characterization of 13 patients. Developmental delay and speech abnormalities were common to all and comparable in frequency and severity to previously reported cases. Array-based comparative genomic hybridization showed the deletions to vary from 95 kb to 8.5 Mb. We also carried out high-resolution 244K array comparative genomic hybridization in 10 of 13 patients, that defined the proximal and distal breakpoints of each deletion and helped determine the size, extent, and gene content within the deletion. Two patients had a smaller 95 kb terminal deletion with breakpoints within the SHANK3 gene while three other patients had a similar 5.5 Mb deletion implying the recurrent nature of these deletions. The two largest deletions were found in patients with ring chromosome 22. No correlation could be made with deletion size and phenotype although complete/partial SHANK3 was deleted in all patients. There are very few reports on array comparative genomic hybridization analysis on patients with the 22q13.3 deletion syndrome, and we aim to accurately characterize these patients both clinically and at the molecular level, to pave the way for further genotype-phenotype correlations. (c) 2010 Wiley-Liss, Inc.

Markedly inhibited 7-dehydrocholesterol-delta 7-reductase activity in liver microsomes from Smith-Lemli-Opitz homozygotes.

We investigated the enzyme defect in late cholesterol biosynthesis in the Smith-Lemli-Opitz syndrome, a recessively inherited developmental disorder characterized by facial dysmorphism, mental retardation, and multiple organ congenital anomalies. Reduced plasma and tissue cholesterol with increased 7-dehydrocholesterol concentrations are biochemical features diagnostic of the inherited enzyme defect. Using isotope incorporation assays, we measured the transformation of the precursors, [3 alpha- 3H]lathosterol and [1,2-3H]7-dehydrocholesterol into cholesterol by liver microsomes from seven controls and four Smith-Lemli-Opitz homozygous subjects. The introduction of the double bond in lathosterol at C-5[6] to form 7-dehydrocholesterol that is catalyzed by lathosterol-5-dehydrogenase was equally rapid in controls and homozygotes liver microsomes (120 +/- 8 vs 100 +/- 7 pmol/mg protein per min, P = NS). In distinction, the reduction of the double bond at C-7 [8] in 7-dehydrocholesterol to yield cholesterol catalyzed by 7-dehydrocholesterol-delta 7-reductase was nine times greater in controls than homozygotes microsomes (365 +/- 23 vs 40 +/- 4 pmol/mg protein per min, P < 0.0001). These results demonstrate that the pathway of lathosterol to cholesterol in human liver includes 7-dehydrocholesterol as a key intermediate. In Smith-Lemli-Opitz homozygotes, the transformation of 7-dehydrocholesterol to cholesterol by hepatic microsomes was blocked although 7-dehydrocholesterol was produced abundantly from lathosterol. Thus, lathosterol 5-dehydrogenase is equally active which indicates that homozygotes liver microsomes are viable. Accordingly, microsomal 7-dehydrocholesterol-delta 7-reductase is inherited abnormally in Smith-Lemli-Opitz homozygotes.

Status of the myocardium and infarct-related coronary artery in 19 necropsy patients with acute recanalization using pharmacologic (streptokinase, r-tissue plasminogen activator), mechanical (percutaneous transluminal coronary angioplasty) or combined types of reperfusion therapy.

In acute myocardial infarction, myocardial salvage is dependent on rapid restoration of blood flow. Pharmacologic (streptokinase, recombinant tissue-type plasminogen activator), mechanical (percutaneous transluminal coronary angioplasty, guide wire perforation) or combined forms of reperfusion therapy can accomplish this goal, but their effects on infarcted myocardium and vessel occlusion site have not been compared at necropsy. The heart of 19 necropsy patients who had received various forms of acute reperfusion therapy was studied: 14 had pharmacologic or combined forms of reperfusion therapy (13 streptokinase and 1 tissue-type plasminogen activator, including 4 with combined balloon angioplasty) and 5 had had purely mechanical (balloon angioplasty) reperfusion therapy. Reperfusion was initially clinically successful in all 19 patients with the average time from onset of symptoms to reperfusion being 3.7 hours. Necropsy observations separated the 19 patients into distinct subgroups based on changes in the myocardium and infarct-related coronary arteries. Of the 19 patients, 14 (74%) had hemorrhagic myocardial infarction and they all received pharmacologic or combined forms of reperfusion therapy. The remaining five patients (26%) had nonhemorrhagic (anemic) infarction and were treated with balloon angioplasty therapy alone. Increased luminal cross-sectional area was present in 8 of 9 patients with acute balloon angioplasty but severe coronary atherosclerotic plaque remained in 9 of 10 patients without acute balloon angioplasty. Severe hemorrhage surrounded angioplasty sites in all four patients who also received streptokinase or tissue-type plasminogen activator. Severe bleeding at the angioplasty site compromised the dilated coronary lumen in one patient. No patient with angioplasty alone had intraplaque bleeding. Thus, acute coronary balloon angioplasty reperfusion therapy alone appears to avoid the potentially adverse effects of myocardial and intraplaque hemorrhage while simultaneously increasing luminal cross-sectional area at the site of acute occlusion.

Redistribution of Mn++-dependent pyrimidine 5'-nucleotidase (MDPNase) activity during shedding and phagocytosis.

Ultrastructural cytochemistry was used to localize a previously undescribed retinal enzyme activity, ie, "manganese-dependent pyrimidine 5'-nucleotidase" (MDPNase) activity in retinas from rats raised in cyclic light and killed at various times in the lighting cycle. In retinas fixed during the last 3 hr of darkness, at the beginning of the shedding period, heavy cytochemical staining was observed over the extracellular surfaces of the apical processes of the retinal pigment epithelium (RPE) cells. The adjacent distal ends of the rod outer segments (ROS), ensheathed by the apical processes, were also stained along their surfaces. During the first 3 hr after light onset, at the time of maximal shedding and phagocytic activity, the tips of the ROS and ROS phagosomes were heavily labeled with reaction product distributed throughout the interdisc spaces. The RPE apical processes, previously heavily stained, were at this time weakly reactive relative to the ROS tips and phagosomes. After the shedding peak (4-8 hr after light onset), the tips of the ROS were no longer labeled with reaction product, and the apical processes were unreactive. The proximal portions of the ROS were weakly stained throughout the lighting cycle. The observed patterns of redistribution of MDPNase activity before, during, and after the shedding peak suggest that the presence of the enzyme in the ROS tips may be correlated with shedding. Changes in the staining of the RPE apical processes in relation to cyclic light further suggest that this enzyme may be transferred from the apical processes to the ROS tips prior to shedding.

Distribution of microtubules in cultured RPE cells from normal and dystrophic RCS rats.

Indirect immunofluorescence and antibodies to tubulin were used to visualize the distribution of microtubules (MT) in short-term primary cultures of retinal pigment epithelial (RPE) cells isolated from the eyes of control RCS rats and those with inherited retinal degeneration. At all stages of cell spreading in vitro, the pigment granules (PG) in these cells remained tightly clustered in the perinuclear region, surrounded by numerous MT. Initially, in relatively round cells, the perinuclear region was encompassed by a closely woven ring of circularly arranged MT. At later stages of spreading, the ring had disappeared and MT running in various directions could be observed. Cells that were plated singly assumed at first a discoid, then stellate, shape during spreading, whereas, those plated in small groups formed colonies of wedge-shaped cells. In well-spread single cells or colonies, a brightly fluorescent zone that appeared to contain the highest density of MT within the cells was located between the PG-containing perinuclear region and the spreading edges of the cells. A single prominent star-shaped structure from which a number of MT radiated was situated among the PG in the perinuclear region of each cell; we believe this structure corresponds to the centrioles. It was generally well-separated from the regions of highest MT density. No differences in cell shape or in the distribution of MT, centriole-containing regions or PG in spreading or fully spread cells were detected when RPE cells from normal and dystrophic RCS rats were compared. Thus, the distribution of MT and their assembly during cell spreading appear normal in RPE cells of the dystrophic rat.

Gomez-Lopez-Hernandez syndrome: expansion of the phenotype.

Gomez-Lopez-Hernandez syndrome (cerebello-trigeminal-dermal dysplasia) is a condition that includes abnormalities of the cerebellum (rhombencephalosynapsis), cranial nerves (trigeminal anesthesia), and scalp (alopecia). Seven patients with this condition have been documented since 1979. We now report a male with Gomez-Lopez-Hernandez syndrome who, at the age of 19 years, is the oldest patient identified to date. He has been followed since birth, allowing us to report on the progression of his physical findings and psychiatric problems including hyperactivity, depression, self-injurious behavior and bipolar disorder. In addition, he has short stature and growth hormone deficiency.

Possible new autosomal recessive syndrome of lymphedema, hydroceles, atrial septal defect, and characteristic facial changes.

We describe two brothers with congenital lymphedema of lower limbs, atrial septal defect (ASD), and similar facial appearance. A sister had severe hydrops fetalis, ASD, omphalocele, and other anomalies. This combination of congenital lymphedema and ASD differs from other reported cases of congenital lymphedema and most likely constitutes a previously unrecognized autosomal recessive syndrome.

Clinical effects of cholesterol supplementation in six patients with the Smith-Lemli-Opitz syndrome (SLOS)

We describe the clinical effects of cholesterol supplementation in 6 children with the RSH-"Smith-Lemli-Opitz" syndrome (SLOS). The children ranged in age from birth to 11 years at the onset of therapy, with pretreatment cholesterol levels ranging from 8 to 62 mg/dl. Clinical benefits of therapy were seen in all patients, irrespective of age at onset of treatment, or severity of cholesterol defect. Effects of treatment included improved growth, more rapid developmental progress, and a lessening of problem behaviors. Pubertal progression in older patients, a better tolerance of infection, improvement of gastrointestinal symptoms, and a diminution in photosensitivity and skin rashes were also noted. There were no adverse reactions to treatment with cholesterol. This preliminary study suggests that cholesterol supplementation may be of benefit to patients with the SLOS.

Abnormal cholesterol metabolism in the Smith-Lemli-Opitz syndrome: report of clinical and biochemical findings in four patients and treatment in one patient.

We report on four patients with the Smith-Lemli-Opitz (SLO) syndrome who appear to have a defect in cholesterol biosynthesis. The initial results of therapy of one of the patients with cholesterol and bile acids to correct her metabolic abnormalities are described. This finding provides a biochemical marker to help in the diagnosis of this syndrome, may provide insight into the pathogenesis of this disorder, and have therapeutic and prenatal diagnostic implications as well.

Treatment of Smith-Lemli-Opitz syndrome: results of a multicenter trial.

Patients with the RSH or Smith-Lemli-Optiz syndrome (SLOS) have an inborn error of cholesterol biosynthesis which results in a deficiency of cholesterol and an elevation of the cholesterol precursor, 7-dehydrocholesterol. A treatment protocol consisting of administration of cholesterol +/- bile acids was initiated in an attempt to correct the biochemical abnormalities seen. Fourteen patients (8 female, 6 male: ages 2 months to 15 years) have now been treated for 6-15 months. Three patients received cholesterol alone, while 11 patients received cholesterol and one or more bile acids. Biochemical improvement in sterol levels and in the ratio of cholesterol to total sterols was noted in all patients. The most marked improvement was noted in patients presenting with initial cholesterol levels < 40 mg/dl. No toxicity was observed. Clinical improvement in growth and neurodevelopmental status was also observed.

Skeletal anomalies and deformities in patients with deletions of 22q11.

Skeletal anomalies in patients with a 22q11.2 deletion are reported infrequently. We report the skeletal findings in 108 patients with a 22q11.2 deletion, of whom 37 (36%) had a skeletal anomaly. Twenty-two patients (20%) had anomalies of the limbs, 7 of the upper limb, including preaxial or postaxial polydactyly. An anomaly of the lower limb was found in 16 patients, including postaxial polydactyly, clubfoot, severely overfolded toes, and 2-3 toe cutaneous syndactyly. Chest films of 63 patients were examined; 30% of them had abnormal findings, most commonly supernumerary ribs (17%) or a "butterfly" vertebral body (11%). Hypoplastic vertebrae, hemivertebrae, and vertebral coronal clefts were also noted. Thus, skeletal anomalies are not uncommon in patients with a 22q11.2 deletion and may occur more frequently than recognized previously.

Mental status screening of emergency department patients: normative study of the quick confusion scale.

OBJECTIVE: In order to increase the utility of the Quick Confusion Scale (QCS), a six-item, 15-point instrument used in screening for impaired mental status in an emergency department (ED) setting, clinical norms were established for an ED patient population. METHODS: The QCS was administered to ED patients of a university-based hospital during a nine-week period. All subjects scoring less than 15 on the QCS were also administered the Mini-Mental State Examination (MMSE); 731 patients provided QCS scores for use in this study and 295 provided MMSE scores in addition to their QCS scores. RESULTS: The internal consistency of the QCS was found to be within acceptable limits given that the briefness of the scale forced restriction in the variability coefficient. QCS scores were converted to a standardized metric (percentile ranks), population parameters were consulted, and two cutoff scores were established: one that suggests the likelihood of a cognitive impairment, signaling a need for further evaluation (QCS score of 11); and one that indicates an almost certain cognitive impairment (QCS score of 7). Percentile rank comparisons between subjects' scores on the MMSE and on the QCS provided additional validity for the cutoff scores. CONCLUSIONS: The QCS, in its focus on providing a quickly obtained, easily calculated, and readily interpreted score, presents a viable alternative to currently existing practices for assessing mental status in ED patients.

Cerebral infarction in Menkes' disease.

Menkes' disease is an X-linked disorder caused by impaired intracellular transport of copper. Currently, no therapy effectively arrests the relentless neurodegeneration of Menkes' disease. Previous neuroimaging reports of patients with Menkes' disease describe a range of abnormalities, including intracranial vessel tortuosity and cerebral white matter changes. We report two infants with Menkes' disease who developed ischemic cerebrovascular disease early in infancy. Magnetic resonance studies, including diffusion-weighted imaging and proton magnetic resonance spectroscopy, demonstrated bilateral infarctions of deep gray matter nuclei, a finding not previously described in Menkes' disease. Potential mechanisms for these cerebrovascular lesions in Menkes' disease include the susceptibility to free radical attack and inadequate energy supply from oxidative phosphorylation. These infarctions may play an unrecognized but important role in the neurodegeneration of children with Menkes' disease. The development of effective therapeutic agents against this disease will require a more detailed understanding of such underlying mechanisms.

Screening for metabolic disorders. How are we doing?

Routine screening for phenylketonuria and congenital hypothyroidism has become an integral part of pediatric practice in the United States. Screening for several other metabolic disorders is now entering the second or third decade of use. New information is available for the pediatrician for both groups of disorders that will be of help in caring for children in the years to come.

Cytochemical localization of Mn2+-dependent pyrimidine 5'-nucleotidase activity in isolated rod outer segments.

A cytochemical method was developed for localization in isolated rod outer segments of manganese-dependent pyrimidine 5'-nucleotidase (MDPNase), an enzyme activity with possible relevance to shedding that we recently reported in photoreceptors and retinal pigment epithelial (RPE) cells in the intact rat retina. The purpose of this study was to eliminate the possibility that the previously observed cytochemical staining of the rods was due to diffusion of reaction product from the RPE cell lysosomes, which were also heavily stained. Rod outer segments (ROS) were isolated on continuous sucrose gradients from retinal homogenates prepared from rats raised in cyclic light (12 hr light:12 hr dark) and killed during the first 2 hr after light onset. ROS-containing bands were removed from the gradients and the isolated rods were fixed in 0.25% glutaraldehyde and pelleted. Chopped sections of the pellets were incubated in cytochemical medium for MDPNase activity and processed for light- and electron-microscopic localization of the enzyme activity. Two patterns of cytochemical staining were seen in ROS isolated from retinas obtained at this time of day. A few of the pellets contained clusters of ROS that were heavily coated along their surfaces and seemingly interconnected by thick strands of highly reactive extracellular material that displayed a punctate pattern of cytochemical staining. This material may have originated from the apical processes of the RPE cells, which were heavily stained in tissue fixed in situ around the time of light onset. The second staining pattern, visible only by electron microscopy, was more commonly observed. In the majority of the isolated ROS profiles, discrete streaks of cytochemical reaction product were seen in association with the internal aspects of the discs, at sites that seemed to correspond to the rims, and to narrow zones within the disc interiors. This distribution of reactive sites closely resembled that observed over most of the length of the ROS in the intact retina fixed at the same time of day. Occasionally, ROS profiles were encountered in which additional reactive sites were localized to the interdisc spaces between the plasma membrane and the rims of the discs. The latter pattern resembled the distribution of reaction product seen during this period over the tips of the ROS fixed in situ. As in the intact retinas, the cytochemical staining of the isolated ROS was inhibited by fluoride ions and strongly stimulated by manganese ions.(ABSTRACT TRUNCATED AT 400 WORDS)