Increased membrane turnover in the brain in cutaneous anthrax without central nervous system disorder: a magnetic resonance spectroscopy study.

Cutaneous anthrax, caused by Bacillus anthracis contacting the skin, is the most common form of human anthrax. Recent studies implicate the presence of additional, possibly toxin-related subtle changes, even in patients without neurological or radiological findings. In this study, the presence of subtle changes in cutaneous anthrax was investigated at the metabolite level using magnetic resonance spectroscopy. Study subjects were consisted of 10 patients with cutaneous anthrax without co-morbid disease and/or neurological findings, and 13 healthy controls. There were no statistical differences in age and gender between two groups. The diagnosis of cutaneous anthrax was based on medical history, presence of a typical cutaneous lesion, large gram positive bacilli on gram staining and/or positive culture for B. anthracis from cutaneous samples. Brain magnetic resonance imaging examination consisted of conventional imaging and single-voxel magnetic resonance spectroscopy. Magnetic resonance spectroscopy was performed by using point-resolved spectroscopy sequence (TR: 2000ms, TE: 136ms, 128 averages). Voxels of 20mm×20mm×20mm were placed in normal-appearing parietal white matter to detect metabolite levels. Cerebral metabolite peaks were measured in normal appearing parietal white matter. N-acetyl aspartate/creatine and choline/creatine ratios were calculated using standard analytical procedures. Patients and controls were not statistically different regarding parietal white matter N-acetyl aspartate/creatine ratios (p=0.902), a finding that implicates the conservation of neuronal and axonal integrity and neuronal functions. However, choline/creatine ratios were significantly higher in patient groups (p=0.001), a finding implicating an increased membrane turnover. In conclusion, these two findings point to a possibly anthrax toxins-related subtle inflammatory reaction of the central nervous system at the cellular level.

Ciprofloxacin-induced urticaria and tenosynovitis: a case report.

BACKGROUND: Tendon disorders are rare events associated with fluoroquinolone congestion. Skin reactions are more frequent than tendon disorders. We reported this case as the combination of ciprofloxacin-induced urticaria and tenosynovitis has been unreported in young women. CASE: A 28-year-old woman without underlying disease developed urticarias and tendinopathy 4 days after the initiation of ciprofloxacin treatment for urinary infection. MRI of the left foot revealed increased synovial fluid surrounding the tendon of the flexor hallucis longus muscle representing tenosynovitis. Ciprofloxacin was ceased due to the possibility of ciprofloxacin-induced tendinopathy and urticaria. Complete resolution of her symptoms and findings occurred 3 days after discontinuation of ciprofloxacin without any additional treatment. CONCLUSION: Early discontinuation of fluoroquinolone therapy when tendinopathy is suspected is the basis of therapy. So, it should be kept in mind that fluoroquinolone-induced tendinopathy may occur in an otherwise healthy young patient with no risk factors and in a site other than the Achilles tendon.

Evaluation of in vivo cerebral metabolism on proton magnetic resonance spectroscopy in patients with impaired glucose tolerance and type 2 diabetes mellitus.

The aim of this study was to investigate possible metabolic alterations in cerebral tissues on magnetic resonance spectroscopy (MRS) in patients with impaired glucose tolerance (IGT) and with type 2 diabetes mellitus (T2-DM). Twenty-five patients with T2-DM, 13 patients with IGT, and 14 healthy volunteers were included. Single-voxel spectroscopy (TR: 2000 ms, TE: 31 ms) was performed in all subjects. Voxels were placed in the frontal cortex, thalamus, and parietal white matter. N-acetylaspartate (NAA)/creatine (Cr), choline (Cho)/Cr, and myo-inositol (MI)/Cr ratios were calculated. Frontal cortical Cho/Cr ratios were increased in patients with IGT compared to control subjects. Parietal white matter Cho/Cr ratios were significantly higher in patients with IGT when compared to patients with T2-DM. In the diabetic group, frontal cortical MI/Cr ratios were increased, and parietal white matter Cho/Cr ratios were decreased when compared to the control group. Frontal cortical NAA/Cr and Cho/Cr ratios and parietal white matter Cho/Cr ratios were decreased in diabetic patients with poor glycemic control (A1C>10%). A1C levels were inversely correlated with frontal cortical NAA/Cr and Cho/Cr ratios and with parietal white matter Cho/Cr ratios. T2-DM and IGT may cause subtle cerebral metabolic changes, and these changes may be shown with MRS. Increased Cho/Cr ratios may suggest dynamic change in membrane turnover in patients with IGT. Diabetic patients with poor glycemic control may be associated with neuronal dysfunction/damage in brain in accordance with A1C levels and, in some, extend with insulin resistance.

Spontaneous intracranial hypotension with pituitary adenoma.

Spontaneous intracranial hypotension (SIH) is an unusual syndrome that is characterised by positional headache, neck rigidity, nausea and vomiting. The characteristic magnetic resonance imaging (MRI) findings are diffuse smooth pachymeningeal thickening and enhancement, downward displacement of posterior fossa structures and pituitary gland enlargement. An unusual case of SIH with pituitary macro-adenoma and subsequent subdural haemorrhage is presented, and its clinical picture, MRI findings and possible pathophysiological mechanism are discussed.

Cerebral diffusional changes in the early phase of anthrax: is cutaneous anthrax only limited to skin?

OBJECTIVES: Characteristics of cerebral diffusion in the acute period of the anthrax infection were investigated to understand the pathophysiology of the disease. METHODS: Six cutaneous anthrax patients (mean age: 33.3, SD: 18.1) and six healthy control subjects (mean age: 33.7, SS: 19.6) were examined at the acute phase of the infection with diffusion weighted imaging on 1.5 T scanner. ADC values were measured from five different cerebral locations. T-tests, logistic regression and ROC curves were used. RESULTS: Anthrax patients were significantly different than controls regarding cortical ADC values (p<0.05). Logistic regression model accurately classified five out of the six anthrax cases (83.3%). A cut-off value of 574 mm2/s x 10(-3) was found by using ROC curve coordinates. A sensitivity of 100% and a specificity of 67% were attained by means of this value. CONCLUSIONS: This study shows the existence of cerebral parenchymal changes at microstructural level in cutaneous anthrax without neurological findings. These changes are possibly related to the components of the toxin. Our results support the general but unproven opinion that anthrax treatment does not change the existence and the effects of the toxin. Pathophysiological mechanisms towards classification should therefore be reviewed.

Protective role of melatonin in pinealectomized rat brains: in vivo magnetic resonance spectroscopic analysis.

The goal of this study was to investigate the effect of melatonin on basic cerebral metabolites in pinealectomized (Px) rat brains. Twenty-one rats were randomly divided into three groups with seven rats per group. The study groups included sham-operated rats, Px rats and Px rats treated with melatonin. Melatonin administration began at 60 days following pinealectomy and continued for 21 days. At the end of the study, in vivo single voxel magnetic resonance spectroscopy was performed on whole brains to determine choline (Cho), creatine and N-acetyl aspartate (NAA) concentrations. Px rats had significantly lower NAA levels (P<0.05), and significantly higher Cho levels (P<0.05) when compared with sham-operated rats. Administration of melatonin had normalized NAA and Cho levels in Px rats. We propose that pinealectomy causes significant changes in cerebral metabolites which are compatible with neural loss. Melatonin administration prevents the disruptive effects of pinealectomy on brain tissue.

Selective intraarterial nimodipine treatment in an experimental subarachnoid hemorrhage model.

BACKGROUND AND PURPOSE: Cerebral vasospasm secondary to subarachnoid hemorrhage (SAH) has been a serious clinical problem. The aim of the present study is to evaluate the efficacy of selective intraarterial (IA) nimodipine treatment in a rabbit model of chronic cerebral vasospasm. METHODS: Twenty-two adult New-Zealand rabbits of either sex, weighing 2500-3800 g were used for this study. Following a control angiography, all animals received 1 mL of fresh unheparinized autologuous arterial blood into the cisterna magna. Three days later, the presence of vasospasm was demonstrated angiographically by selective vertebral artery injection. The experimental design was as follows: separate groups of animals (n = 5, in each group) received nimodipine (0.05 mg/kg), papaverine (6 mg/kg), or vehicle intraarterially, after placement of a microcatheter into the vertebral artery. Another group (n = 5) received nimodipine (0.05 mg/kg) directly into the cisterna magna, and vehicle injection was made into cisterna magna in two other animals. Thirty minutes after treatment, angiographies were repeated and changes in arterial diameter were expressed as percentages of control. RESULTS: IA nimodipine and IA papaverine were effective in relieving veretebral and basilary vasospasm (P < .05). IA nimodipine was more effective than IA papaverine (P < .05). IA nimodipine was not more effective than intrathecal (IT) nimodipine in relieving vertebral artery vasospasm, although it was more effective than IT nimodipine in basilar artery. Vehicle injections (IA or IT) failed to reverse the vasospasm induced by autologuous blood injection. CONCLUSION: This study showed that selective IA nimodipine treatment may be considered as an alternative in the treatment of chronic vasospasm following SAH.

Sonographic evaluation of the carpal tunnel after provocative exercises.

OBJECTIVE: Dynamic carpal tunnel syndrome (CTS) is a subtype of CTS in which symptoms usually subside with rest and return with repetitive motions. In this subgroup, nerve conduction studies, performed at rest, are often inconclusive. In this study, the diagnostic value of provocative sonography was evaluated in patients with dynamic CTS. METHODS: Twenty wrists of 13 patients with dynamic CTS and 10 control subjects were investigated with sonography before and immediately after provocative exercises imitating work-related stresses. In addition to conventional indices (palmar displacement, nerve area at the middle level, and swelling ratio before and after exercise), 2 newly formed indices (provocative nerve area ratio and provocative palmar displacement ratio) were investigated. RESULTS: In the pre-exercise period, there were no significant differences between patients and control subjects regarding palmar displacement and the swelling ratio. The difference was significant (P =.035) for the nerve area at the middle level. In the post-exercise period, all parameters were significantly different between patients and control subjects. The nerve area at the middle level and the swelling ratio had higher significance (P <.0001) than palmar displacement (P =.015). The post-exercise swelling ratio had the highest sensitivity (95%) in diagnosing dynamic CTS when a cutoff value of 1.26 was used. The provocative palmar displacement ratio had high sensitivity (80%) and the highest specificity (90%) for a cutoff value of 1.28. CONCLUSIONS: Provocative exercises increase sensitivity and specificity and contribute to the sonographic diagnosis of dynamic CTS. This examination should be performed if electrodiagnostic test results are negative.

MR imaging of meniscal bucket-handle tears: a review of signs and their relation to arthroscopic classification.

Our objective was to review the MR imaging signs of meniscal bucket-handle tears and assess the relevance of these signs to the arthroscopic classification of displaced meniscal tears. Forty-five menisci in 42 patients who had a diagnosis of bucket-handle tear either on MR imaging or on subsequent arthroscopy (in which Dandy's classification of meniscal tears was used) were retrospectively analyzed for MR imaging findings of double posterior cruciate ligament (PCL), fragment within the intercondylar notch, absent bow tie, flipped meniscus, double-anterior horn, and disproportional posterior horn signs. Arthroscopy, which was considered as the gold standard, revealed 41 bucket-handle tears (either diagnosed or not diagnosed by MR imaging) in 38 patients (33 males, 5 females). There was a statistically significant male preponderance for the occurrence of meniscal bucket-handle tears. Overall, sensitivity and positive predictive value of MR imaging for the detection of meniscal bucket-handle tears were calculated as 90%. Common MR imaging signs of meniscal bucket-handle tears in arthroscopically proven cases of such tears were the fragment in the notch and absent bow tie signs (98% frequency for each). Double-PCL, flipped meniscus, double-anterior horn, and disproportional posterior horn signs, however, were less common (32, 29, 29, and 27%, respectively). An arthroscopically proven bucket-handle tear was found in all patients who displayed at least three of the six MR imaging signs of meniscal bucket-handle tears. The presence of three or more MR imaging signs of meniscal bucket-handle tears is highly suggestive of this condition.