Clinical characteristics, pathogens implicated and therapeutic outcomes of mixed infection in adult bacterial meningitis

We reviewed retrospectively the data for adult patients with bacterial meningitis over a period of 10.5 years in our hospital. The clinical characteristics and laboratory data of the 21 cases (52 strains) of mixed infection were analyzed. Two hundred and fifteen cases of single pathogen adult bacterial meningitis (ABM) were also included for comparison. Post-neurosurgical type of ABM was presented in 86% of the mixed infection group. Brain abscess was found in three patients. Fourteen patients survived and seven cases died. The analysis showed a statistical significance for the mixed infection group having a higher rate of nosocomially-acquired, post-neurosurgical condition, hydrocephalus, and lower level of cerebrospinal fluid white cell count, protein and lactate than the single pathogen group. Logistic regression analysis showed the independent factor of "hydrocephalus" (p = 0.002). Presence of hydrocephalus is a significant neuroimaging feature when compared with the single pathogen group. As compared with the previous study results of mixed infection in ABM, the present study showed a change of pathogens implicated of increasing Pseudomonas spp. and Acinetobacter spp. infections, and an emergence of anaerobic pathogens. All these changes deserve special attention because of the need for an appropriate choice of empirical antibiotics and choice of culture method.

Peroxisome proliferator-activated receptors γ/mitochondrial uncoupling protein 2 signaling protects against seizure-induced neuronal cell death in the hippocampus following experimental status epilepticus

Background

Status epilepticus induces subcellular changes that may lead to neuronal cell death in the hippocampus. However, the mechanism of seizure-induced neuronal cell death remains unclear. The mitochondrial uncoupling protein 2 (UCP2) is expressed in selected regions of the brain and is emerged as an endogenous neuroprotective molecule in many neurological disorders. We evaluated the neuroprotective role of UCP2 against seizure-induced hippocampal neuronal cell death under experimental status epilepticus.

Methods

In Sprague–Dawley rats, kainic acid (KA) was microinjected unilaterally into the hippocampal CA3 subfield to induce prolonged bilateral seizure activity. Oxidized protein level, translocation of Bcl-2, Bax and cytochrome c between cytosol and mitochondria, and expression of peroxisome proliferator-activated receptors γ (PPARγ) and UCP2 were examined in the hippocampal CA3 subfield following KA-induced status epilepticus. The effects of microinjection bilaterally into CA3 area of a PPARγ agonist, rosiglitazone or a PPARγ antagonist, GW9662 on UCP2 expression, induced superoxide anion (O₂^{· -}) production, oxidized protein level, mitochondrial respiratory chain enzyme activities, translocation of Bcl-2, Bax and cytochrome c, and DNA fragmentation in bilateral CA3 subfields were examined.

Results

Increased oxidized proteins and mitochondrial or cytosol translocation of Bax or cytochrome c in the hippocampal CA3 subfield was observed 3–48 h after experimental status epilepticus. Expression of PPARγ and UCP2 increased 12–48 h after KA-induced status epilepticus. Pretreatment with rosiglitazone increased UCP2 expression, reduced protein oxidation, O₂^{· -} overproduction and dysfunction of mitochondrial Complex I, hindered the translocation of Bax and cytochrome c, and reduced DNA fragmentation in the CA3 subfield. Pretreatment with GW9662 produced opposite effects.

Conclusions

Activation of PPARγ upregulated mitochondrial UCP2 expression, which decreased overproduction of reactive oxygen species, improved mitochondrial Complex I dysfunction, inhibited mitochondrial translocation of Bax and prevented cytosolic release of cytochrome c by stabilizing the mitochondrial transmembrane potential, leading to amelioration of apoptotic neuronal cell death in the hippocampus following status epilepticus.

Mitochondrial dysfunction and oxidative stress promote apoptotic cell death in the striatum via cytochrome c/caspase-3 signaling cascade following chronic rotenone intoxication in rats

Parkinson's disease (PD) is a progressive neurological disorder marked by nigrostriatal dopaminergic degeneration. Evidence suggests that mitochondrial dysfunction may be linked to PD through a variety of different pathways, including free-radical generation and dysfunction of the mitochondrial Complex I activity. In Lewis rats, chronic systemic administration of a specific mitochondrial Complex I inhibitor, rotenone (3 mg/kg/day) produced parkinsonism-like symptoms. Increased oxidized proteins and peroxynitrite, and mitochondrial or cytosol translocation of Bim, Bax or cytochrome c in the striatum was observed after 2-4 weeks of rotenone infusion. After 28 days of systemic rotenone exposure, imunohistochemical staining for tyrosine hydroxylase indicated nigrostriatal dopaminergic neuronal cell degeneration. Characteristic histochemical (TUNEL or activated caspase-3 staining) or ultrastructural (electron microscopy) features of apoptotic cell death were present in the striatal neuronal cell after chronic rotenone intoxication. We conclude that chronic rotenone intoxication may enhance oxidative and nitrosative stress that induces mitochondrial dysfunction and ultrastructural damage, resulting in translocation of Bim and Bax from cytosol to mitochondria that contributes to apoptotic cell death in the striatum via cytochrome c/caspase-3 signaling cascade.

Ultrasonographic assessment of carpal tunnel syndrome of mild and moderate severity in diabetic patients by using an 8-point measurement of median nerve cross-sectional areas

Background

Using high-resolution ultrasonography (US) to measure the median nerve cross-sectional areas (CSAs) such as in the “inching test” conducted in nerve conduction studies is a valuable tool to assess carpal tunnel syndrome (CTS). However, using this US measurement method to assess the median nerve CSA in diabetic patients with CTS has rarely been reported. Therefore, we used this US measurement method in this study to measure median nerve CSAs and to compare the CSAs of idiopathic, diabetic and diabetic polyneuropathy (DPN) patients with CTS.

Methods

124 hands belonging to 89 participants were included and assigned into four groups: control (32), idiopathic (38), diabetic (38) and DPN (16) CTS. In the latter two groups, only patients with mild and moderately severe CTS were included. The median nerve CSAs were measured at 8 points marked as i4, i3, i2, i1, w, o1, o2, and o3 in the inching test. The measured CSAs in each group of participants were compared.

Results

Compared with the CSAs of the control group, enlarged CSAs were found in the idiopathic, diabetic and DPN CTS groups. The CSAs were larger at i4, i3 and i2 in the diabetic CTS group compared to the idiopathic CTS group. The CSAs measured at the i1 and w levels of the DPN CTS group were smaller than those of the diabetic CTS group. In the diabetic CTS group, the cut-off values of CSAs measured at the inlet, wrist crease, and outlet were 15.3 mm², 13.4 mm² and 10.0 mm², respectively, and 14.0 mm², 12.5 mm² and 10.5 mm², respectively, in the DPN CTS group.

Conclusions

Compared with the median nerve CSAs of the control and idiopathic CTS groups, the median nerve CSAs of the diabetic patients with CTS were significantly enlarged. However, compared with the diabetic CTS group, the CSAs were significantly smaller in the DPN CTS group. This US 8-point measurement method can be of value as an important complementary tool for CTS studies and diagnosis among diabetic patients.

Clinical significance of serological biomarkers and neuropsychological performances in patients with temporal lobe epilepsy

Background

Temporal lobe epilepsy (TLE) is a common form of focal epilepsy. Serum biomarkers to predict cognitive performance in TLE patients without psychiatric comorbidities and the link with gray matter (GM) atrophy have not been fully explored.

Methods

Thirty-four patients with TLE and 34 sex - and age-matched controls were enrolled for standardized cognitive tests, neuroimaging studies as well as measurements of serum levels of heat shock protein 70 (HSP70), S100ß protein (S100ßP), neuronal specific enolase (NSE), plasma nuclear and mitochondrial DNA levels.

Results

Compared with the controls, the patients with TLE had poorer cognitive performances and higher HSP70 and S100ßP levels (p < 0.01). The patients with higher frequencies of seizures had higher levels of HSP70, NSE and S100ßP (p < 0.01). Serum HSP70 level correlated positively with duration of epilepsy (σ = 0.413, p < 0.01), and inversely with memory scores in the late registration (σ = −0.276, p = 0.01) and early recall score (σ = −0.304, p = 0.007). Compared with the controls, gray matter atrophy in the hippocampal and parahippocampal areas, putamen, thalamus and supplementary motor areas were found in the patient group. The HSP70 levels showed an inverse correlation with hippocampal volume (R square = 0.22, p = 0.007) after controlling for the effect of age.

Conclusions

Our results suggest that serum biomarkers were predictive of higher frequencies of seizures in the TLE group. HSP70 may be considered to be a stress biomarker in patients with TLE in that it correlated inversely with memory scores and hippocampal volume. In addition, the symmetric extratemporal atrophic patterns may be related to damage of neuronal networks and epileptogenesis in TLE.

Clinical characteristics and prognosis of acute bacterial meningitis in elderly patients over 65: a hospital-based study

Background

To examine the clinical characteristics of bacterial meningitis in elderly patients.

Methods

261 patients with adult bacterial meningitis (ABM), collected during a study period of 11 years (2000-2010), were included for study. Among them, 87 patients aged ≥ 65 years and were classified as the elderly group. The clinical and laboratory characteristics and prognostic factors were analyzed, and a clinical comparison with those of non-elderly ABM patients was also made.

Results

The 87 elderly ABM patients were composed of 53 males and 34 females, aged 65-87 years old (median = 71 years). Diabetes mellitus (DM) was the most common underlying condition (34%), followed by end stage renal disease (7%), alcoholism (4%) and malignancies (4%). Fever was the most common clinical manifestation (86%), followed by altered consciousness (62%), leukocytosis (53%), hydrocephalus (38%), seizure (30%), bacteremia (21%) and shock (11%). Thirty-nine of these 87 elderly ABM patients had spontaneous infection, while the other 48 had post-neurosurgical infection. Forty-four patients contracted ABM in a community-acquired state, while the other 43, a nosocomial state. The therapeutic results of the 87 elderly ABM patients were that 34 patients expired and 53 patients survived. The comparative results of the clinical and laboratory characteristics between the elderly and non-elderly ABM patients showed that only peripheral blood leukocytosis was significant. Presence of shock and seizure were significant prognostic factors of elderly ABM patients.

Conclusions

Elderly ABM patients accounted for 34.8% of the overall ABM cases, and this relatively high incidence rate may signify the future burden of ABM in the elderly population in Taiwan. The relative frequency of implicated pathogens of elderly ABM is similar to that of non-elderly ABM. Compared with non-elderly patients, the elderly ABM patients have a significantly lower incidence of peripheral blood leukocytosis. The mortality rate of elderly ABM remains high, and the presence of shock and seizures are important prognostic factors.

Spinal epidural abscess in adults caused by Staphylococcus aureus: clinical characteristics and prognostic factors

OBJECTIVE

Spinal epidural abscess (SEA) is a devastating infectious disease, which may result in neurologic sequelae. Staphylococcus (S.) aureus is a common pathogen of SEA. Here, we analyzed the clinical characteristics and laboratory data of adult patients with S. aureus SEA and compared the clinical characteristics of methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) infections.

METHODS

Between 2003 and 2008, we collected data regarding 29 adult cases of S. aureus SEA and analyzed the clinical presentations, magnetic resonance (MR) imaging features, therapeutic outcome, and prognostic factors. Antibiotic susceptibility test results of 11 implicated MRSA strains were also further analyzed.

RESULTS

We identified 17 MSSA strains and 12 MRSA strains. Lumbar and lumbosacral spine segments were the most commonly involved segments. All 29 patients had back pain. Other findings included sensory abnormalities (25), motor weakness (21), fever (16), bladder dysfunction (16), and altered consciousness (3). Disease onset at admission was acute in 6 cases and chronic in 23. The stages of disease severity were early stage in 9 and late stage in 20. After therapy, 21 patients had a good prognosis and 8 had a poor prognosis. Significant prognostic factors included older age (>70years), presence of diabetes mellitus, adrenal insufficiency, and MRSA infection. The prognosis alone was clinically different between patients with MSSA and MRSA infections.

CONCLUSIONS

Patients with localized back pain, particularly those with a fever and compromised immune system, should undergo MR imaging to ensure an early diagnosis and management.

Ultrasonographic median nerve cross-section areas measured by 8-point "inching test" for idiopathic carpal tunnel syndrome: a correlation of nerve conduction study severity and duration of clinical symptoms

BACKGROUND

Incremental palmar stimulation of the median nerve sensory conduction at the wrist, the "inching test", provides an assessment with reference to segments proximal and distal to the entrapment. This study used high-resolution ultrasonography (US) to measure the median nerve's cross-section areas (CSAs) like the "inching test" and to correlate with the nerve conduction study (NCS) severity and duration of carpal tunnel syndrome (CTS).

METHODS

Two hundred and twelve (212) "CTS-hands" from 135 CTS patients and 50 asymptomatic hands ("A-hands") from 25 control individuals were enrolled. The median nerve CSAs were measured at the 8-point marked as i4, i3, i2, i1, w, o1, o2, and 03 in inching test. The NCS severities were classified into six groups based on motor and sensory responses (i.e., negative, minimal, mild, moderate, severe, and extreme). Results of US studies were compared in terms of NCS severity and duration of clinical CTS symptoms.

RESULTS

There was significantly larger CSA of the NCS negative group of "CTS-hands" than of "A-hands". The cut-off values of the CSAs of the NCS negative CTS group were 12.5 mm2, 11.5 mm2 and 10.1 mm2 at the inlet, wrist crease, and outlet, respectively. Of the 212 "CTS-hands", 32 were NCS negative while 40 had minimal, 43 mild, 85 moderate, 10 severe, and two extreme NCS severities. The CSAs of "CTS-hands" positively correlated with different NCS severities and with the duration of CTS symptoms. By duration of clinical symptoms, 12 of the 212 "CTS-hands" were in the 1 month group; 82 in >1 month and ≤ 12 months group, and 118 in >12 months group. In "inching test", segments i4-i3 and i3-i2 were the most common "positive-site". The corresponding CSAs measured at i4 and i3, but not at i2, were significantly larger than those measured at points that were not "positive-site".

CONCLUSIONS

Using the 8-point measurement of the median nerve CSA from inlet to outlet similar to the "inching test" has positive correlations with NCS severity and duration of CTS clinical symptoms, and can provide more information on anatomic changes. Combined NCS and US studies using the 8-point measurement may have a higher positive rate than NCS alone for diagnosing CTS.

Sleep quality and daytime sleepiness in patients with epilepsy

PURPOSE

Poor sleep quality and excessive daytime sleepiness (EDS) are common complaints of patients with epilepsy (PWE). This study aimed to evaluate possible predisposing factors for EDS and subjective sleep quality in PWE.

METHODS

One hundred and seventeen PWE were enrolled and 30 healthy volunteers were recruited as controls. EDS was evaluated by the Epworth Sleepiness Scale (ESS) while the Pittsburg Sleep Quality Index (PSQI) was designed to evaluate overall sleep quality. Clinical baseline data and possible risk factors for sleep disturbances were included in the statistical analysis.

RESULTS

Twenty percent of PWE (23/117) and 7% of healthy controls (2/30) had excessive daytime sleepiness (p = 0.007). PWE had significantly higher PSQI total scores (6.5 ± 3.8 vs. 3.7 ± 2.9), sleep latency (1.2 ± 0.8 vs. 0.6 ± 0.7) and sleep efficiency (0.8 ± 1.0 vs. 0.0 ± 0.2) scores than the controls (all p < 0.001). A significantly higher prevalence of poor sleep quality was found in the partial seizure, non-seizure-free, and polytherapy groups (all p < 0.05). Multivariate analysis showed that poor seizure control was the strongest independent risk factor for poor sleep quality (OR = 2.43, 95% CI = 1.15-5.15, p = 0.02).

CONCLUSION

EDS and poor sleep quality are common in PWE and are closely related to partial epilepsy, poor seizure control, and polytherapy. These relationships must be addressed in order to provide the best management of sleep disturbance in such patients.

Roles of oxidative stress, apoptosis, PGC-1α and mitochondrial biogenesis in cerebral ischemia

The primary physiological function of mitochondria is to generate adenosine triphosphate through oxidative phosphorylation via the electron transport chain. Overproduction of reactive oxygen species (ROS) as byproducts generated from mitochondria have been implicated in acute brain injuries such as stroke from cerebral ischemia. It was well-documented that mitochondria-dependent apoptotic pathway involves pro- and anti-apoptotic protein binding, release of cytochrome c, leading ultimately to neuronal death. On the other hand, mitochondria also play a role to counteract the detrimental effects elicited by excessive oxidative stress. Recent studies have revealed that oxidative stress and the redox state of ischemic neurons are also implicated in the signaling pathway that involves peroxisome proliferative activated receptor-γ (PPARγ) co-activator 1α (PGC1-α). PGC1-α is a master regulator of ROS scavenging enzymes including manganese superoxide dismutase 2 and the uncoupling protein 2, both are mitochondrial proteins, and may contribute to neuronal survival. PGC1-α is also involved in mitochondrial biogenesis that is vital for cell survival. Experimental evidence supports the roles of mitochondrial dysfunction and oxidative stress as determinants of neuronal death as well as endogenous protective mechanisms after stroke. This review aims to summarize the current knowledge focusing on the molecular mechanisms underlying cerebral ischemia involving ROS, mitochondrial dysfunction, apoptosis, mitochondrial proteins capable of ROS scavenging, and mitochondrial biogenesis.

Activation of calcium/calmodulin-dependent protein kinase IV and peroxisome proliferator-activated receptor γ coactivator-1α signaling pathway protects against neuronal injury and promotes mitochondrial biogenesis in the hippocampal CA1 subfield after transient global ischemia

Delayed neuronal cell death occurs in the vulnerable CA1 subfield of the hippocampus after transient global ischemia (TGI). We demonstrated previously, based on an experimental model of TGI, that the significantly increased content of oxidized proteins in hippocampal CA1 neuron was observed as early as 30 min after TGI, followed by augmentation of PGC-1α expression at 1 hr, as well as up-regulation of mitochondrial uncoupling protein 2 (UCP2) and superoxide dismutases 2 (SOD2). Using the same animal model, the present study investigated the role of calcium/calmodulin-dependent protein kinase IV (CaMKIV) and PGC-1α in delayed neuronal cell death and mitochondrial biogenesis in the hippocampus. In Sprague-Dawley rats, significantly increased expression of nuclear CaMKIV was noted in the hippocampal CA1 subfield as early as 15 min after TGI. In addition, the index of mitochondrial biogenesis, including a mitochondrial DNA-encoded polypeptide, cytochrome c oxidase subunit 1 (COX1), and mitochondrial number significantly increased in the hippocampal CA1 subfield 4 hr after TGI. Application bilaterally into the hippocampal CA1 subfield of an inhibitor of CaMKIV, KN-93, 30 min before TGI attenuated both CaMKIV and PGC-1α expression, followed by down-regulation of UCP2 and SOD2, decrease of COX1 expression and mitochondrial number, heightened protein oxidation, and enhanced hippocampal CA1 neuronal damage. This study provides correlative evidence for the neuroprotective cascade of CaMKIV/PGC-1α which implicates at least in part the mitochondrial antioxidants UCP2 and SOD2 as well as mitochondrial biogenesis in ischemic brain injury.

Learning and error patterns in the Chinese Verbal Learning Test in subjects with mild cognitive impairment and normal elderly

PURPOSE

The discrimination between normal elderly (NC) and those with mild cognitive impairment (MCI) is of clinical relevance since the conversion from MCI to Alzheimer dementia (AD) is high.

METHODS

This study enrolled 216 amnestic MCI patients and 103 NC from our memory clinics and assessed whether the learning curve, recall and cued scores, as well as error patterns from the Chinese Version Verbal Learning Test (CVVLT) helped to distinguish between these two groups.

RESULTS

Our results revealed that subjects with MCI had a lower rate of acquisition and deceleration of learning in the learning curve. The MCI group also showed a lower retention rate and recall scores as compared with the NC group. Further, the error patterns offered discrimination values between the two groups in total number of perseverations, intrusion in the cued recall, as well as prototypic and unrelated errors in recognition. An inverse correlation was seen between memory scores and error patterns.

CONCLUSION

This study suggests that by combining the learning and error patterns from the verbal memory test, patients with MCI can be better differentiated from normal elderly.

The clinical characteristics, therapeutic outcome, and prognostic factors of non-tuberculous bacterial spinal epidural abscess in adults: a hospital-based study

PURPOSE

Nontuberculous bacterial spinal epidural abscess (SEA) is a serious infectious disease of spines. Despite proper management, SEA remains a disease of high morbidity. The epidemiological data in southern Taiwan is still lacking.

METHODS

We analyzed the clinical features, laboratory data, magnetic resonance imaging findings, and therapeutic results of 45 bacterial SEA patients, collected during a study period of six years (2003- 2008).

RESULTS

The 45 adult SEA patients, 32 were men and 13 women, aged 17-81 years (mean = 62 years). Thoracic and lumbosacral spines were the most commonly affected segments. Staphylococcus aureus was the most commonly implicated pathogen, accounting for infections in 67% (29/43) of the culture-proven cases, and 41% (12/29) of the S. aureus strains were oxacillin resistant. Gram-negative pathogens were implicated in 30% (13/43) of the culture-proven cases. Of the 45 patients, 19 underwent antibiotic treatment alone and 26 underwent medical and surgical treatments. The therapeutic results showed that 28 patients had a good prognosis and 17 had a poor prognosis. The significant prognostic factors included higher age, presence of diabetes mellitus and chronic heart disease, and initial presentation of altered consciousness.

CONCLUSION

S. aureus was the most commonly implicated pathogen of adult SEA, and most S. aureus strains were oxacillin resistant. A relatively high incidence of Gram-negative infection was observed in this study. The epidemiological characteristics of the implicated pathogens must receive special consideration when selecting the empirical antibiotics. Despite adequate management, many adults with bacterial SEA had a high incidence of poor prognosis.

Neuromuscular abnormality and autonomic dysfunction in patients with cerebrotendinous xanthomatosis

BACKGROUND

Cerebrotendinous xanthomatosis (CTX) is a rare lipid-storage disease. Neuromuscular abnormality and autonomic system (ANS) dysfuction in CTX are rarely examined in large-scale studies in the literature. We studied the peripheral nervous system, myopathology, and autonomic system of four CTX patients and performed a literature review of the reported CTX patients with peripheral neuropathy.

METHODS

Four biochemically and genetically confirmed CTX patients, belonging to two families, were included for study and all received nerve conduction study (NCS), muscle biopsy for histopathologic and ultrastructural study, skin biopsy for intraepidermal nerve fiber (INEF) density measurement, autonomic testings including sympathetic skin response, R-R interval variation and head-up tilt test using an automated tilt table to record the changes of blood pressure and heart rate in different postures. The Q-Sweat test was also applied for the detection of sweat amount and onset time of response. The clinical characteristics, study methods and results of 13 studies of peripheral neuropathy in CTX patients in the literature were also recorded for analysis.

RESULTS

The results of NCS study showed axonal sensory-motor polyneuropathy in three CTX cases and mixed axonal and demyelinating sensor-motor polyneuropathy in one. The myopathological and histopathologic studies revealed mild denervation characteristics, but the ultrastructural study revealed changes of mitochondria and the membranous system, and increased amounts of glycogen, lipofuscin and lipid deposition. The ANS study revealed different degrees of abnormalities in the applied tests and the INEF density measurement showed small fiber neuropathy in three of the four CTX patients. The literature review of peripheral neuropathy in CTX revealed different types of peripheral neuropathy, of which axonal peripheral neuropathy was the most common.

CONCLUSIONS

Peripheral neuropathy, especially the subtype of axonal sensori-motor neuropathy, is common in patients with CTX. Evidence of lipid metabolic derangement in CTX can be reflected in ultrastructural studies of muscles. With an adequate multi-parametric evaluation, a high incidence of ANS abnormalities can be seen in this rare lipid-storage disease, and a high incidence of small fiber involvement is also reflected in the IENF density measurement of skin biopsies.

Clinical characteristics and therapeutic outcomes of nosocomial super-infection in adult bacterial meningitis

BACKGROUND

Super-infection in adult bacterial meningitis (ABM) is a condition wherein the cerebrospinal fluid (CSF) grows new pathogen(s) during the therapeutic course of meningitis. It is an uncommon but clinically important condition rarely examined in literature.

METHODS

Twenty-seven episodes of super-infection states in 21 ABM patients collected in a 9.5-year study period (January 2001 to June 2010) were evaluated. The clinical characteristics, implicated pathogens, results of antimicrobial susceptibility tests, and therapeutic outcomes were analyzed.

RESULTS

Twenty-one patients (13 men, 8 women) aged 25-73 years (median, 45 years) had post-neurosurgical state as the preceding event and nosocomial infection. The post-neurosurgical states included spontaneous intracranial hemorrhage (ICH) with craniectomy or craniotomy with extra-ventricular drainage (EVD) or ventriculo-peritoneal shunt (VPS) in 10 patients, traumatic ICH with craniectomy or craniotomy with EVD or VPS in 6 patients, hydrocephalus s/p VPS in 2 patients, and one patient each with cerebral infarct s/p craniectomy with EVD, meningeal metastasis s/p Omaya implant, and head injury. All 21 patients had EVD and/or VP shunt and/or Omaya implant during the whole course of ABM. Recurrent fever was the most common presentation and the implicated bacterial pathogens were protean, many of which were antibiotic resistant. Most patients required adjustment of antibiotics after the pathogens were identified but even with antimicrobial therapy, 33.3% (7/21) died. Morbidity was also high among survivors.

CONCLUSIONS

Super-infection in ABM is usually seen in patients with preceding neurosurgical event, especially insertion of an external drainage device. Repeat CSF culture is mandatory for diagnostic confirmation because most of the implicated bacterial strains are non-susceptible to common antibiotics used. Unusual pathogens like anaerobic bacteria and fungi may also appear. Despite antimicrobial therapy, prognosis remains poor.

The potential role of mitochondrial dysfunction in seizure-associated cell death in the hippocampus and epileptogenesis

Epilepsy is considered one of the most common neurological disorders worldwide. The burst firing neurons associated with prolonged epileptic discharges could lead to a large number of changes with events of cascades at the cellular level. From its role as the cellular powerhouse, mitochondria also play a crucial role in the mechanisms of cell death. Emerging evidence has shown that prolonged seizures may result in mitochondrial dysfunction and increase of oxidative and nitrosative stress in the hippocampus that precede neuronal cell death and cause subsequent epileptogenesis. The selective dysfunction of mitochondrial respiratory chain Complex I has been suggested to be a biochemical hallmark of seizure-induced neuronal cell death and epileptogenesis. Therefore, protection of mitochondria from bioenergetic failure and oxidative stress in the hippocampus may open a new vista to the development of effective neuroprotective strategies against seizure-induced brain damage and to the design of novel treatment perspectives against therapy-resistant forms of epilepsy.

Cerebellar bacterial brain abscess: report of eight cases

PURPOSE

To analyze the clinical characteristics and therapeutic outcome of patients with solely cerebellar bacterial brain abscess (BBA).

CASE REPORT

Eight patients with solely cerebellar BBA, collected during a period of 23 years from 210 BBA patients, were included in this study. The eight patients were five men and three women, aged 5-54 years (mean, 36.6 years). Six of them were adults, one was a child, and one was an adolescent. Six patients had underlying medical/surgical problems. Of the clinical presentations, dizziness was the most common (87.5%, 7/8), followed by headache (62.5%, 5/8), altered consciousness (62.5%, 5/8), fever (50%, 4/8), ataxia (25%, 2/8), hearing impairment (12.5%, 1/8), dysarthria (12.5%, 1/8), and hemiparesis (12.5%, 1/8). The Image Severity Index (ISI) scores of these eight patients ranged from 6 to 12 points. All eight patients received both medical and surgical treatment. One patient died owing to a complication in the neurosurgical procedure and the remaining patients survived. The therapeutic outcome was quantified one month after discharge by modified Rankin scale (mRS) and the result showed six of the seven survivors had good outcomes, while the other one had a poor outcome (ataxic gait).

CONCLUSION

Cerebellar BBA accounted for 3.8% (8/210) of the overall BBA. In cerebellar BBA, dizziness is a frequent symptom. Early diagnosis and a combination of antimicrobial and neurosurgical intervention is important for its treatment. The small case number is a limitation of this study; therefore, further large-scale study of cerebellar BBA is needed for better delineation of the clinical characteristics, therapeutic outcome, and prognostic factors.

Acute/subacute cerebral infarction (ASCI) in HIV-negative adults with cryptococcal meningoencephalitis (CM): a MRI-based follow-up study and a clinical comparison to HIV-negative CM adults without ASCI

BACKGROUND

Acute/subacute cerebral infarction (ASCI) in HIV-negative cryptococcal meningoencephalitis (CM) adults has rarely been examined by a series of MRI-based follow-up study. We studied a series of MRI follow-up study of CM adults and compared the clinical characters of those with ASCI and those without ASCI.

METHODS

The clinical characteristics and a series of brain MRI findings of seven CM adults with ASCI were enrolled for analysis. The clinical characteristics of another 30 HIV-negative CM adults who did not have ASCI were also included for a comparative analysis.

RESULTS

The seven HIV-negative CM adults with ASCI were four men and three women, aged 46-78 years. Lacunar infarction was the type of ASCI, and 86% (6/7) of the ACSI were multiple infarctions distributed in both the anterior and posterior cerebrovascular territories. The seven CM patients with ASCI were significantly older and had a higher rate of DM and previous stroke than the other 30 CM adults without ASCI. They also had a higher incidence of consciousness disturbance at presentation and had a poor prognosis.

CONCLUSION

ASCI was found in 18.9% (7/37) of HIV-negative CM adults. Serial MRI follow-up studies may allow a better delineation of ASCI in this specific group of infectious disease and multiple lacunar infarctions was the most common type. Older in age and presence of DM and previous stroke were the significant underlying conditions. CM patients with ASCI also had a poor therapeutic outcome.

Central nervous system involvement in hepatocellular carcinoma: clinical characteristics and comparison of intracranial and spinal metastatic groups

From January 1993 to December 2006 we analyzed the clinical characteristics of patients with hepatocellular carcinoma (HCC) with central nervous system (CNS) metastasis at the Kaohsiung Chang Gung Memorial Hospital, Taiwan. Forty-six patients with HCC and CNS metastasis were identified, of whom 36 had intracranial metastasis and 10 had spinal metastasis. The clinical presentations, laboratory data and imaging studies were collected and analyzed. The age at the time of HCC diagnosis ranged from 34 to 78 years; CNS metastasis occurred between 0 and 85 months after diagnosis and death followed between 0 and 93 months later. The Glasgow Coma Scale (GCS) score at the time of CNS metastasis ranged from 7 to 15 and the Child-Pugh score at diagnosis of HCC ranged from 5 to 15. Patients with spinal metastasis had a higher GCS score and lower Child-Pugh score at diagnosis. None of the serum biochemical studies showed unique abnormalities. From the data currently available, intracranial metastasis is the most common site of CNS metastasis of HCC. Advances in treating and diagnosing HCC have improved patient outcomes remarkably; however, CNS metastasis continues to have a grave prognosis. Without a specific biomarker for predicting CNS involvement in HCC, a high index of suspicion for the diagnosis should be maintained, particularly in HCC hyperendemic areas such as Taiwan.

Star fruit intoxication in a patient with moderate renal insufficiency presents as a posterior reversible encephalopathy syndrome

PURPOSE

Star fruit has been reported to contain neurotoxins that often cause severe neurological complications in patients with uremia or severe chronic renal insufficiency. However, the occurrence of neurotoxicity in patients with mild or moderate renal insufficiency has rarely been mentioned.

CASE REPORT

A 67-year-old woman who had diabetes mellitus and moderate renal insufficiency presented with acute onset of hiccups and nausea two hours after ingestion of one fresh star fruit. She further presented with progressively incoherent speech, echolalia and bizarre behavior. On the next day, her consciousness level declined to deep coma and she experienced two seizures. Brain magnetic resonance imaging examinations revealed a focal cerebral lesion over the left occipital area. The clinical symptoms recovered and the brain lesion reversed after emergency hemodialysis.

CONCLUSION

The clinicians should be aware that star fruit intoxication must be considered when patients with a chronic renal disease, even mild or moderate chronic renal insufficiency, present with unexplained neurological or psychiatric symptoms. Emergency hemodialysis or other replacement therapies may be required for the management of acute star fruit intoxication.

Transcriptional upregulation of nitric oxide synthase II by nuclear factor-kappaB promotes apoptotic neuronal cell death in the hippocampus following experimental status epilepticus

Whereas status epilepticus, or the condition of continuous epileptic seizures, produces a characteristic pattern of preferential neuronal cell loss in the hippocampus, the underlying mechanism is still unsettled. Based on an experimental model of temporal lobe status epilepticus, we demonstrated previously that prolonged seizures prompted an overproduction of nitric oxide (NO) by upregulation of NO synthase II (NOS II) in the hippocampal CA3 subfield, followed by the activation of mitochondrial apoptotic signaling cascade. Using the same animal model, the present study evaluated the hypothesis that transcriptional upregulation of NOS II gene by nuclear factor-kappaB (NF-kappaB) promotes apoptotic neuronal cell death in the hippocampus following status epilepticus. In Sprague-Dawley rats, significantly augmented nucleus-bound translocation of NF-kappaB p50 and p65 subunits and DNA binding activity of NF-kappaB were observed in hippocampal CA3 neurons as early as 30 min after elicitation of sustained seizure activity by microinjection of kainic acid into the CA3 subfield, followed by a progressive elevation that peaked at 90 min. In addition, application bilaterally into the hippocampal CA3 subfield of a selective NF-kappaB inhibitor, pyrrolidine dithiocarbamate or double-stranded kappaB decoy DNA significantly antagonized the activated NOS II-peroxynitrite signaling cascade (3 hr) and the associated manifestations of apoptotic cell death (7 days) in the hippocampus. We conclude that activation of NF-kappaB in hippocampal CA3 neurons upregulates NOS II gene expression following experimental temporal lobe status epilepticus, leading to apoptotic neuronal cell death in the hippocampus.

Supratentorial deep-seated bacterial brain abscess in adults: clinical characteristics and therapeutic outcomes

PURPOSE

Supratentorial deep-seated bacterial brain abscess (BBA) in adults is rarely examined solely in the literature. This retrospective study is conducted to examine the clinical characteristics and therapeutic outcome of this specific group of BBA.

METHODS

Eight adult patients with supratentorial deep-seated BBA, collected during a study period of 14 years (1994-2007), were enrolled. Their microbiological data derived from cerebrospinal fluid (CSF), blood or pus cultures, clinical features and therapeutic outcome were analyzed.

RESULTS

The eight adult cases were six men and two women, aged 41 to 80 years (mean=61). Preceding medical conditions were found in five of these eight cases, while preceding neurosurgical event was found in one. Of the clinical presentations, hemiparesis (6) was the most common, followed by fever (5), altered consciousness (4), headache (3), septic shock (1), and seizure (1). The main locations of the BBA were the left basal ganglia in five, the left thalamus in two, and the right basal ganglia in one. Causative pathogens were found in six cases and the isolated pathogens were all cultured from CSF specimens. Positive bacteremia which grew K. pneumoniae was found in one case. Seven of these eight cases contracted the infection in a community-acquired state. Besides antibiotic treatment, seven of them received a neurosurgical intervention (stereotactic aspiration and/or ventriculoperitoneal shunt). The therapeutic result showed six cases survived and two expired. Five of the six survivors had variable degree of neurologic deficits.

CONCLUSIONS

Besides the common clinical features of BBA, supratentorial deep-seated BBA has a high incidence of hemiparesis in the early stages of disease. Most of the involved patients have community-acquired infections and are preceded by a medical condition. Stereotactic aspiration for therapeutic and diagnostic purposes, as well as shunting surgery, is the most common neuro-surgical procedures used for treatment. But despite therapeutic efforts, high mortality and morbidity remain.