Heparin-induced thrombocytopenia in essential thrombocytosis.

We report a 67-year-old woman with essential thrombocytosis who developed cerebral infarction and heparin-induced thrombocytopenia during treatment for the cerebral infarction. She developed additional cerebral infarcts, acute femoral artery occlusion, and thrombophlebitis of her lower extremities. She was successfully treated with argatroban. This is the first report of a patient with essential thrombocytosis who developed heparin-induced thrombocytopenia and serious conditions, which included multiple thromboembolisms and coagulation disorders mimicking disseminated intravascular coagulation.

Moyamoya disease presenting as thalamic hemorrhage in a patient with neuromyelitis optica and Sjögren's syndrome.

A 52-year-old woman was admitted to the hospital with right thalamic hemorrhage. A carotid angiogram revealed occlusion of the terminal portions of the bilateral internal carotid arteries with basal moyamoya vessels, which was diagnosed as moyamoya disease (MMD). At 31 years of age, she was diagnosed with multiple sclerosis because of optic neuritis and myelitis. Paraplegia appeared 14 days after admission. T2-weighted thoracic magnetic resonance imaging revealed a high intensity lesion extending from T4 to T6. Her left upper limb was partially paralytic and her lower limbs exhibited paraplegia and dysesthesia. Anti-aquaporin 4 and anti-Sjögren's syndrome-A and -B antibodies were positive. The pathogenesis of neuromyelitis optica may be associated with such immunologic factors, but there are no reports of simultaneous presentations of neuromyelitis optica and MMD. Autoimmunity may be associated with the etiology of MMD.

Purulent meningitis caused by Actinomyces successfully treated with rifampicin: a case report.

A 64-year-old woman presented with fever and headache. Lumbar puncture revealed cerebrospinal fluid (CSF) that contained 67,386 /mm(3) of WBC; CSF culture revealed Actinomyces species. She was diagnosed with purulent meningitis caused by actinomyces, and treated with intravenous ampicillin 12 g/day. The administration of ampicillin was effective, but not sufficient to control the inflammation in CSF. CSF inflammation persisted and a gradual increase in granulation tissue was found in the subdural space on lumbar MRI. After administration of rifampicin 450 mg/day, the CSF was normalized and the enhancement of granulation tissue decreased. The patient completely recovered 5 months after the therapy was initiated. We suggest that rifampicin may be an option for the treatment of meningitis caused by actinomyces.

Quantitative electroencephalogram analysis in dementia with Lewy bodies and Alzheimer's disease.

Clinicopathophysiological differences between dementia with Lewy bodies (DLB) and Alzheimer's disease (AD) remain obscure. Our goals were to determine whether characteristic findings of electroencephalogram (EEG) power and coherence in DLB and a differential pathophysiological mechanism of quantitative EEG existed between DLB and AD. The group consisted of 15 patients with AD or DLB and 12 age-matched controls. Original EEG signals were recorded from 14 scalp electrodes positioned according to the International 10-20 System, using digitally linked earlobes as a reference. Although EEG power spectral analysis showed increasing EEG power density in patients with DLB in the delta and theta bands, such a difference did not exist in patients with AD. Compared with AD, the delta and theta band intrahemispheric coherence values in the fronto-temporo-central regions were higher in DLB. In the beta band, AD was lower than DLB in almost all temporo-centro-parieto-occipital regions. Comparing the mean power value between patients with/without donepezil treatment, there was a significantly lower EEG power density in the delta and theta bands in DLB subjects taking donepezil than in subjects not taking donepezil, whereas there was no significant difference in AD patients. These results suggest that cholinergic dysfunction is stronger in DLB than AD.

Effects of head-down tilt on the intracranial pressure in conscious rabbits.

Head-down tilt (HDT) causes a fluid shift towards the upper body, which increases intracranial pressure (ICP). In the present study, the time course of ICP changes during prolonged exposure to HDT was investigated in conscious rabbits through a catheter chronically implanted into the subarachnoid space. The production of cerebrospinal fluid (CSF) after exposure to 7-days HDT was also examined by a ventriculo-cisternal perfusion method. The ICP increased from 4.3+/-0.4 (mean+/-S.E.M.) mmHg to 8.0+/-0.8 mmHg immediately after the onset of 45 degrees HDT, reached a peak value of 15.8+/-1.9 mmHg at 11 h, and then decreased to 10.4+/-1.1 mmHg at 24 h. During 7-days HDT, it also increased from 4.8+/-0.9 mmHg to 9.2+/-1.6 mmHg immediately after the onset of 45 degrees HDT, reached a peak value of 12.8+/-2.5 mmHg at 12 h of HDT, and then decreased gradually towards the pre-HDT baseline value for 7 days. The rate of CSF production was 10.1+/-0.6 microl/min in rabbits exposed to 7-days HDT, and 9.7+/-0.5 microl/min in control rabbits. These results suggest that the rabbits begin to adapt to HDT within a few days and that the production of CSF is preserved after exposure to 7-days HDT. The time course of ICP changes during HDT in conscious rabbits seems to be considerably different from that in anesthetized rabbits.

Age-dependent changes of postischemic reperfusion in rat skin.

Ischemia-reperfusion plays a certain role in causing skin damage associated with pressure sores. In this study, changes in cutaneous hemodynamics during reperfusion were investigated in young and older rats. After cessation of 1-hour or 2-hour ischemia, the skin blood flow increased transiently (postischemic hyperemia) and quickly returned to the baseline in young and older rats. After 4-hour ischemia, however, the postischemic hyperemia was reduced in both groups, and the skin blood flow decreased below the baseline for a few hours in older rats. The skin blood flow tolerated well the repeated exposures to 1-hour ischemia in both groups. In 2-hour ischemia experiments, the postischemic hyperemia was preserved after the second ischemic period in young rats but not in older rats. These results suggest that the tolerance of skin microcirculation to ischemia-reperfusion may decrease with increasing age.

Effects of head-down tilt on cerebral blood flow and somatosensory-evoked potentials in rabbits.

Changes in cerebral blood flow (CBF) and somatosensory-evoked potentials (SEPs) were studied in rabbits exposed to head-down tilt (HDT) at 45 degrees and 75 degrees. The animals were anesthetized with alpha chloralose and the lungs were artificially ventilated. CBF was continuously measured by laser Doppler flowmetry (LDF), and SEPs were recorded as responses of the cortex to median nerve stimulation. In the 45 degrees HDT rabbits, CBF did not change significantly in the parietal cortex during 1 h of HDT. In contrast, in the 75 degrees HDT rabbits, CBF did not change significantly within 5 min after the onset of HDT, but decreased gradually to 79% of the pre-HDT baseline value at the end of 1 h of HDT. The latency and amplitude of SEPs did not change significantly throughout the experiment in any group. These results suggest that CBF and SEPs do not change significantly during 1 h of 45 degrees HDT and that 75 degrees HDT disturbs the regulation of the cerebral circulation but does not affect cortical somatosensory response, at least for 1 h.