Diffusion tensor tractography and neuropsychological assessment in patients with vitamin B12 deficiency

Introduction

Structural imaging of the brain does not demonstrate any changes in a vast majority of patients with vitamin B12 deficiency, even in advanced stages. In this study, we aimed to assess and correlate the functional integrity of the brain fiber tracts using diffusion tensor tractography with neuropsychological examination in patients with vitamin B12 deficiency.

Methods

The study was conducted at two tertiary care centers. Thirty-two patients with vitamin B12 deficiency were enrolled and subjected to diffusion tensor tractography, as an extension of diffusion tensor imaging, and neuropsychological assessment. Tests of significance were done to detect changes, pre- and post-vitamin B12 supplementation in the diffusivity parameters (fractional anisotropy and mean diffusivity) and the neuropsychological test scores.

Results

Statistically significant changes were observed in the diffusivity parameters and the neuropsychological test scores between the controls and the patients with vitamin B12deficiency in the pre- and post-treatment phases.

Conclusions

This is the first study to evaluate the diffusion tensor tractography (DTT) parameters in the light of clinical neuropsychological assessment in patients with vitamin B12 deficiency. Utilization of DTT parameters may antedate structural changes and may quantify the neurocognitive deficits.     

Gastric emptying in patients with chronic liver diseases

There have been a number of reports of gastric emptying in cirrhosis, all with unconfirmed results. Moreover, the mechanism for delayed emptying in cirrhotic patients is unclear. We evaluated gastric emptying in patients with chronic hepatitis and cirrhosis by means of gastric emptying scintigraphy. METHODS: The subjects were 18 normal controls and 75 patients with chronic viral hepatitis (50 patients had chronic hepatitis and 25 patients had cirrhosis). Tc-99m diethyltriamine pentaacetic acid labeled solid meals were used to evaluate gastric emptying; the half-time (T 1/2) of which was calculated. Digestive symptom scores were determined at the time of gastric emptying tests. RESULTS: Fourteen (28%) of 50 patients with chronic hepatitis and 16 (64%) of 25 patients with cirrhosis had delayed gastric emptying. T 1/2 in patients with cirrhosis was significantly higher than that in normal controls and patients with chronic hepatitis (p = 0.0001 and 0.0003, respectively). The difference between T 1/2 in patients with chronic hepatitis and that in normal controls was not significant. On regression analysis, two indices-the serum albumin level and platelet count-were found to be significantly related to delayed gastric emptying. CONCLUSIONS: Gastric emptying was more delayed in cirrhotic patients than in those with chronic hepatitis and normal controls. Delayed gastric emptying may be related to liver function and portal hypertension.     

胃食管反流病的胃排空功能研究

目的　探讨胃食管反流病 (GERD)胃液体、固体排空情况及与pH值监测结果的相关性。方法　 15例GERD患者分别进行胃镜检查、2 4h食管pH值监测和放射性核素胃排空功能测定 ,与对照组液体和固体胃排空率、胃半排空时间进行比较 ,分析GERD患者液体、固体排空率与食管炎及 2 4hpH值监测指标之间的关系。结果　GERD组液体胃排空率在 15、30min明显低于对照组 (P<0 0 5 ) ,固体胃排空率在各时间点均低于对照组 (P <0 0 5 )。GERD患者液体半排空时间与pH值监测总积分无相关性 (r=0 0 6 1,P >0 0 5 ) ;固体半排空时间与pH值监测总积分呈直线相关 (r=0 6 43,P <0 0 5 )。结论　GERD患者存在胃液体、固体排空延迟。固体半排空时间与pH值总积分呈直线相关。胃排空延迟可能是GERD发病机制的重要因素。     

Neurologic manifestations of vitamin B-12 deficiency in a military hospital

Although it is well recognized that patients with cobalamin (vitamin B-12) deficiency can develop neuropsychiatric problems, primary care physicians do not frequently realize that patients presenting with only vague neurologic complaints can have vitamin B-12 deficiency as the etiology. During a 1-year period, six patients presented to the Neurology Clinic at Brooke Army Medical Center, Fort Sam Houston, Texas, after evaluation at the primary care level for their neurologic complaints. All six had cobalamin deficiency, and none were anemic. Military primary care physicians should be aware of the various neurologic presentations of these patients.     

婴儿维生素B1缺乏性脑病的CT诊断(附25例分析)

目的 :探讨婴儿维生素B1缺乏性脑病的CT表现特点 ,提高临床诊断水平。方法 :回顾性分析 2 5例经临床证实的婴儿维生素B1缺乏性脑病患者的临床和CT资料。结果 :2 5例脑CT扫描均显示为双基底节 (壳核、苍白球、尾状核 )对称性低密度影 ,呈圆形或斑片状 ,可伴有脑白质低密度病变、脑萎缩、脑软化。结论 :CT对婴儿维生素B1缺乏性脑病的诊断具有重要价值。     

A racial difference in serum vitamin B12 levels

Measurements of the serum Vitamin B12 concentrations of 49 black and 49 white healthy adults demonstrate a significantly higher mean serum Vitamin B12 level in blacks when compared to whites (p less than 0.001). The reason for this difference appears to be genetic, although environmental factors may also be involved. It is suggested that clinical laboratories should establish their own separate reference values of serum Vitamin B12 for blacks and whites in order to prevent misinterpretation of test results.     

Gastric emptying with repeated drinking during running and bicycling

The high prevalence of gastrointestinal complaints in long-distance runners makes the movements specific to this type of exercise suspected of causing a disruption of normal gastrointestinal function. Gastric emptying rate is one indicator thereof. In the present study trained volunteers performed similar repeated fluid ingestion tests while running and while bicycling for 80 min at 70% VO2max. Control tests at rest were also conducted. Two drinks containing carbohydrate were tested, one hypertonic, and one isotonic. Artificially sweetened water was used as a control. Gastric emptying rate of the isotonic drink, expressed as a percentage of the volume in the stomach at the beginning of each measurement period, did not differ between cycling and running during the first 40 min and was faster during cycling than during running between 40 and 80 min. With the hypertonic drink no differences between cycling and running were observed. In comparing gastric emptying rates after each sequential bolus, at rest, the isotonic drink was observed to maintain a high emptying rate, equal to that of water, whereas the hypertonic drink emptied more slowly after the first 20-min period. A similar pattern was observed during both running and cycling. The isotonic drink continued to empty quickly after the initial 20 min, whereas GE rate of the hypertonic drink decreased after the initial 20 min.     

A survey and critical evaluation of a dual isotope (Dicopac) vitamin B12 absorption test

The results of all dual isotope tests (2142) carried out on 1989 patients, 807 males (40.6%) and 1182 females (59.4%), during a 10 year period (1976–1985 inclusive) in the Grampian Health Board Area (population 497,272) have been reviewed. Patient age ranged from 5–95 years with 45.5% over 60 years. The referring specialities were Gastroenterology (47.6%), Haematology (11.3%), Paediatries (2.1%) and all others (39.9%). According to the manufacturer's recommended criteria, results were classified as normal in 1054 (49.2%), abnormal in 659 (30.8%), equivocal in 337 (15.7%) and unsatisfactory in 92 (4.3%) tests. Vitamin B₁₂ malabsorption of ileal type was indicated in 544 tests (25.4%) and of gastric type in 115 (5.4%). Of the latter, 76 were related to pernicious anaemia, 10 to previous gastric surgery and 2 to gastric carcinoma. Of the 337 patients with equivocal results, 138 patients were reviewed and 115 (83.3%) found to have a documented cause for gastric malabsorption (96 pernicious anaemia and 19 previous gastric surgery). In 172 patients with proven pernicious anaemia the manufacturer's recommended criteria for gastric malabsorption were completely satisfied in only 76 (44.3%) but 167 (96.5%) had an excretion ratio 1.3 and 127 (73.8%) a ratio 1.7. Unsatisfactory tests were mainly due to incomplete urine collection (91.3%) or contamination with another isotope (5.4%).     

A survey and critical evaluation of a dual isotope (Dicopac) vitamin B12 absorption test

The results of all dual isotope tests (2142) carried out on 1989 patients, 807 males (40.6%) and 1182 females (59.4%), during a 10 year period (1976-1985 inclusive) in the Grampian Health Board Area (population 497,272) have been reviewed. Patient age ranged from 5-95 years with 45.5% over 60 years. The referring specialties were Gastroenterology (47.6%), Haematology (11.3%), Paediatrics (2.1%) and all others (39.0%). According to the manufacturer's recommended criteria, results were classified as normal in 1054 (49.2%), abnormal in 659 (30.8%), equivocal in 337 (15.7%) and unsatisfactory in 92 (4.3%) tests. Vitamin B12 malabsorption of ileal type was indicated in 544 tests (25.4%) and of gastric type in 115 (5.4%). Of the latter, 76 were related to pernicious anaemia, 10 to previous gastric surgery and 2 to gastric carcinoma. Of the 337 patients with equivocal results, 138 patients were reviewed and 115 (83.3%) found to have a documented cause for gastric malabsorption (96 pernicious anaemia and 19 previous gastric surgery). In 172 patients with proven pernicious anaemia the manufacturer's recommended criteria for gastric malabsorption were completely satisfied in only 76 (44.3%) but 167 (96.5%) had an excretion ratio greater than or equal to 1.3 and 127 (73.8%) a ratio greater than or equal to 1.7. Unsatisfactory tests were mainly due to incomplete urine collection (91.3%) or contamination with another isotope (5.4%).     

小儿维生素B1缺乏性脑病的CT诊断价值

目的 :探讨维生素B1 缺乏性脑病的CT表现特征和诊断价值。方法 :对临床确诊的 12例维生素B1 缺乏性脑病患儿行颅脑常规CT扫描 ,并对其颅脑CT表现及临床资料进行综合分析。结果 :其中对称性的低密度见于尾状核和豆状核 7例 ,豆状核 3例 ,豆状核及颞叶 2例。经CT诊断的该组病例治疗取得明显的效果 ,5例治疗 1周后CT复查 ,2例基底节病灶消失 ,3例病灶明显减小。 2例患儿出现脑瘫后遗症 ,CT显示基底节区有对称性的囊变灶。结论 :小儿维生素B1 缺乏性脑病患儿 ,其颅脑CT表现两侧基底节区对称性的低密度改变有一定特征性 ,CT对该病诊断以及预后判断有重要价值。     

Copper deficiency myeloneuropathy resembling B12 deficiency: partial resolution of MR imaging findings with copper supplementation

Copper deficiency has been associated with a clinical syndrome, myeloneuropathy. Radiographic changes resembling B(12) deficiency in the cervical spinal cord have been described. We present a case of copper deficiency myeloneuropathy, with cervical MR imaging findings resembling B(12) deficiency, which partially reversed following copper supplementation. This is, to our knowledge, the first described case of radiographic improvement with copper supplementation.     

Measurement of total-body cobalt-57 vitamin B12 absorption with a gamma camera

Previously described techniques for the measurement of the absorption of [57Co]vitamin B12 by total-body counting have required an iron room equipped with scanning or multiple detectors. The present study uses simplifying modifications which make the technique more available and include the use of static geometry, the measurement of body thickness to correct for attenuation, a simple formula to convert the capsule-in-air count to a 100% absorption count, and finally the use of an adequately shielded gamma camera obviating the need of an iron room.     

Gastric emptying during prolonged cycling exercise in the heat

Eight trained male cyclists (age 20-33 yr) completed four 3-h bouts of cycling at 60% peak VO2 in the heat (33 degrees C) drinking either water (W), 5% glucose (G), 5% glucose polymer (GP), or 3.2% glucose polymer + 1.8% fructose (GP/F) at a rate of 350 ml every 20 min (3.15 l total volume). Similar changes in heart rate, sweat rate, rectal and mean skin temperatures, and plasma [Na+], [K+], and osmolality were observed during all trials. Mean changes in plasma volume, although not significantly different between trials, were lowest for the GP/F drink (-2.6%) and greatest for the G (-8.1%) drink. Plasma volume decreased (P less than 0.05) below pre-exercise control values during the W, G, and GP trails but was maintained at control values during the GP/F trials. In contrast to water ingestion, G, GP, and GP/F ingestion maintained plasma glucose and respiratory exchange ratios throughout the 3-h exercise bouts. Gastric residual volume (GRV) obtained at the end of exercise was similar for the W, GP, and GP/F trials. The G trials yielded greater (P less than 0.05) GRV than W trials. For all drinks ingested, over 90% of the 3.15 l consumed was emptied from the stomach during the 3-h exercise bouts. At a mean sweat rate of 1.2 l.h-1, cyclists replaced 73% of fluid lost and experienced only a 1.6% loss in body weight. This study demonstrates that, during prolonged (3-h) cycling exercise in the heat, large volumes of W and 5% carbohydrate can be emptied from the stomach to help minimize the effects of dehydration.     

MRI of the spinal cord in myelopathy complicating vitamin B12 deficiency: two additional cases and a review of the literature

Focal spinal cord lesions have been present in all previously reported cases of MRI appearances in myelopathy complicating vitamin B₁₂ deficiency. We describe two further cases showing mild atrophy only and review the salient features of the previous 11 publications. MRI findings reflect quite closely the known pathological changes in this condition. Received: 30 June 1998 Accepted: 1 September 1998     

慢性乙型肝炎患者白细胞介素12B+1188(A/C)位点基因多态性分析

目的 探讨白细胞介素12(IL-12)亚基p40(IL-12B)3'非翻译区+1188(A/C)位点的基因多态性与慢性乙型肝炎的相关性以及对HBV DNA水平的影响.方法 应用聚合酶链反应-限制性片段长度多态性分析(PCR-RFLP)和DNA测序的方法检测157例慢性乙型肝炎患者(慢性乙肝组)和122名健康对照(对照组)IL-12B 3'非翻译区+1188(A/C)位点的基因型,采用荧光定量聚合酶链反应(FQ-PCR)测定慢性乙肝患者的血浆HBV DNA水平.结果 慢性乙肝组IL-12B+1188(A/C)位点AA、AC、CC基因型分布频率分别为34.4%、42.0%、23.6%,对照组三种基因型的分布频率分别为47.5%、39.3%、13.2%.慢性乙肝组与对照组间CC基因型和非CC基因型(AA+AC)之间频率分布差异有统计学意义(X2=4.874,P=0.027;ORCC=1.797,95%CI 1.051～3.073).慢性乙肝组等位基因A、C分布频率分别为55.4%、44.6%,对照组分别为67.2%、32.8%,两组比较差异有统计学意义(X2=8.004,P=0.005;ORA=0.824,95%CI 0.722～0.941;ORC=1.360,95%CI 1.094～1.691);慢性乙肝患者中高水平≥5.0×102拷贝/ml(HBVDNA组)C等位基因分布频率明显高于低水平＜5.0×102拷贝/ml(HBV DNA组),差异有统计学意义(X2=9.750,P=0.002).结论 IL-12B 3'非翻译区+1188(A/C)位点基因多态性与HBV感染相关,其中C等位基因可能是慢性乙肝的遗传易感基因,携带C等位基因的个体可能更有利于HBVDNA的复制.