Value of a novel Neisseria meningitidis--specific polymerase chain reaction assay in skin biopsy specimens as a diagnostic tool in chronic meningococcemia

BACKGROUND: Chronic meningococcemia (CM) is a diagnostic challenge. Skin lesions are frequent but in most cases nonspecific. Polymerase chain reaction (PCR)-based diagnosis has been validated in blood and cerebrospinal fluid for acute Neisseria meningitidis infection, in patients in whom routine microbiologic tests have failed to isolate the bacteria. In 2 patients with CM, we established the diagnosis by a newly developed PCR-based approach performed on skin biopsy specimens. OBSERVATIONS: Two patients presented with fever together with systemic and cutaneous manifestations suggestive of CM. Although findings from blood cultures remained negative, we were able to identify N meningitidis in the skin lesions by a newly developed PCR assay. In 1 patient, an N meningitidis strain of the same serogroup was also isolated from a throat swab specimen. Both patients rapidly improved after appropriate antibiotherapy. CONCLUSIONS: To our knowledge, we report the first cases of CM diagnosed by PCR testing on skin biopsy specimens. It is noteworthy that, although N meningitidis-specific PCR is highly sensitive in blood and cerebrospinal fluid in acute infections, our observations underscore the usefulness of PCR performed on skin lesions for the diagnosis of chronic N meningitidis infections. Whenever possible, this approach should be systematically employed in patients for whom N meningitidis infection cannot be confirmed by routine microbiologic investigations.

Microvascular decompression for trigeminal neuralgia in the elderly: long-term treatment outcome and comparison with younger patients

OBJECTIVE: Multiple studies have proved that microvascular decompression (MVD) is the treatment of choice in cases of medically refractory trigeminal neuralgia (TN). In the elderly, however, the surgical risks related to MVD are assumed to be unacceptably high and various alternative therapies have been proposed. We evaluated the outcomes of MVD in patients aged older than 65 years of age and compared them with the outcomes in a matched group of younger patients. The focus was on procedure-related morbidity rate and long-term outcome. METHODS: This was a retrospective study of 112 patients with TN operated on consecutively over 22 years. The main outcome measures were immediate and long-term postoperative pain relief and neurological status, especially function of trigeminal, facial, and cochlear nerves, as well as surgical complications. A questionnaire was used to assess long-term outcome: pain relief, duration of a pain-free period, need for pain medications, time to recurrence, pain severity, and need for additional treatment. RESULTS: The mean age was 70.35 years. The second and third branches of the trigeminal nerve were most frequently affected (37.3%). The mean follow-up period was 90 months (range, 48-295 months). Seventy-five percent of the patients were completely pain free, 11% were never pain free, and 14% experienced recurrences. No statistically significant differences existed in the outcome between the younger and older patient groups. Postoperative morbidity included trigeminal hypesthesia in 6.25%, hypacusis in 5.4%, and complete hearing loss, vertigo, and partial facial nerve palsy in 0.89% each. Cerebrospinal fluid leak and meningitis occurred in 1 patient each. There were no mortalities in both groups. CONCLUSION: MVD for TN is a safe procedure even in the elderly. The risk of serious morbidity or mortality is similar to that in younger patients. Furthermore, no significant differences in short- and long-term outcome were found. Thus, MVD is the treatment of choice in patients with medically refractory TN, unless their general condition prohibits it.

Effects of Toll-like receptor 2 agonist Pam(3)CysSK(4) on inflammation and brain damage in experimental pneumococcal meningitis

TLR2 signaling participates in the pathogenesis of pneumococcal meningitis. In infant rats, the TLR2 agonist Pam(3)CysSK(4) was applied intracisternally (0.5 microg in 10 microl saline) alone or after induction of pneumococcal meningitis to investigate the effect of TLR2 activation on cerebrospinal fluid (CSF) inflammation and hippocampal apoptosis. A dose effect of Pam(3)CysSK(4) on apoptosis was investigated by intracisternal application of 0.5 microg in 10 microl saline and 40 microg in 20 microl saline. Pam(3)CysSK(4) neither induced apoptosis in sham-operated mice nor aggravated apoptosis in acute infection. However, Pam(3)CysSK(4) induced pleocytosis, TNF-alpha and MMP-9 in CSF in sham-infection but not during acute meningitis. We conclude that TLR2 signaling triggered by Pam(3)CysSK(4) at a dosage capable to induce a neuroinflammatory response does not induce hippocampal apoptosis in the infant rat model of experimental pneumococcal meningitis.

Assessment of a real-time PCR test to diagnose syphilis from diverse biological samples

OBJECTIVES: To investigate the contribution of a real-time PCR assay for the detection of Treponema pallidum in various biological specimens with the secondary objective of comparing its value according to HIV status. METHODS: Prospective cohort of incident syphilis cases from three Swiss hospitals (Geneva and Bern University Hospitals, Outpatient Clinic for Dermatology of Triemli, Zurich) diagnosed between January 2006 and September 2008. A case-control study was nested into the cohort. Biological specimens (blood, lesion swab or urine) were taken at diagnosis (as clinical information) and analysed by real-time PCR using the T pallidum 47 kDa gene. RESULTS: 126 specimens were collected from 74 patients with primary (n = 26), secondary (n = 40) and latent (n = 8) syphilis. Among primary syphilis, sensitivity was 80% in lesion swabs, 28% in whole blood, 55% in serum and 29% in urine, whereas among secondary syphilis, it was 20%, 36%, 47% and 44%, respectively. Among secondary syphilis, plasma and cerebrospinal fluid were also tested and provided a sensitivity of 100% and 50%, respectively. The global sensitivity of T pallidum by PCR (irrespective of the compartment tested) was 65% during primary, 53% during secondary and null during latent syphilis. No difference regarding serology or PCR results was observed among HIV-infected patients. Specificity was 100%. CONCLUSIONS: Syphilis PCR provides better sensitivity in lesion swabs from primary syphilis and displays only moderate sensitivity in blood from primary and secondary syphilis. HIV status did not modify the internal validity of PCR for the diagnosis of primary or secondary syphilis.

Combination of daptomycin plus ceftriaxone is more active than vancomycin plus ceftriaxone in experimental meningitis after addition of dexamethasone

We examined the cerebrospinal fluid penetration of daptomycin after the addition of dexamethasone and its bactericidal efficacy with and without ceftriaxone in an experimental rabbit model of pneumococcal meningitis. The combination of daptomycin with ceftriaxone was the most efficacious regimen for pneumococcal meningitis. The previous addition of dexamethasone affected the antibacterial activity of daptomycin only marginally, either as monotherapy or combined with ceftriaxone, although the penetration of daptomycin into inflamed meninges was significantly reduced from 6 to 2%. Daptomycin with ceftriaxone might be a potential candidate for the empirical therapy of bacterial meningitis, although the activity of this regimen against Listeria monocytogenes remains to be demonstrated.

Cerebral extension of steroid-responsive meningitis arteritis in a boxer

A comatose 30-month-old, entire male boxer was presented because of an acute history of a cluster of three to four seizures. Neurological examination suggested a diffuse to multifocal intracranial lesion. Magnetic resonance tomography revealed symmetrical multifocal to diffuse changes of the cerebral grey matter and ependymal lining with sediment in the lateral ventricles. Haematological examination revealed leucocytosis with neutrophilia. Cerebrospinal fluid examination revealed high protein concentration and polymorphonuclear pleocytosis. Despite antiepileptic treatment, therapy against increased intracranial pressure and antibiosis, the dog's condition continued to deteriorate and he was euthanased. Pathological examination revealed fibrinosuppurative meningo-ependymitis and necrotising arteritis throughout the brain. In addition, chronic inflammation and arterial stenosis was found in the spinal meninges. No infectious agent was found. A diagnosis of steroid-responsive meningitis arteritis was made. The massive extension into the meninges and ventricular system of the forebrain has not been described previously in dogs with steroid-responsive meningitis arteritis and should be considered in the differential diagnosis when an intracranial suppurative infection is suspected.

Molecular identification and epidemiological tracing of Pasteurella multocida meningitis in a baby

We report a case of Pasteurella multocida meningitis in a 1-month-old baby exposed to close contact with two dogs and a cat but without any known history of injury by these animals. 16S rRNA gene sequencing of the isolate from the baby allowed identification at the subspecies level and pointed to the cat as a possible source of infection. Molecular typing of Pasteurella isolates from the animals, from the baby, and from unrelated animals clearly confirmed that the cat harbored the same P. multocida subsp. septica strain on its tonsils as the one isolated from the cerebrospinal fluid of the baby. This case stresses the necessity of informing susceptible hosts at risk of contracting zoonotic agents about some basic hygiene rules when keeping pets. In addition, this study illustrates the usefulness of molecular methods for identification and epidemiological tracing of Pasteurella isolates.

Correspondence of Gonadotropin-Releasing Hormone and Luteinizing Hormone Secretion during Suckling in Postpartum Cows

The hypothalamus in the lower part of the brain contains neurons that produce a small peptide, gonadotropin- releasing hormone (GnRH, LHRH), that regulates luteinizing hormone (LH) secretion by the anterior pituitary gland. Important functions of LH include induction of ovulation in preovulatory follicles during estrus and the luteinization of granulosa cells lining those collapsed follicles to form corpora lutea that produce progesterone during the luteal phase of the estrous cycle or during pregnancy. The production of progesterone by the corpus luteum conveys a negative feed-back action at the central nervous system (CNS) for further episodic secretion of GnRH and in turn, LH secretion. Gonadal removal (i.e., ovariectomy) allows a greater amount of LH secretion to occur during a prolonged period. The objectives of this study were to characterize the pattern of GnRH secretion in the cerebrospinal fluid (CSF) of the bovine third ventricle region of the hypothalamus, determine its correspondence with the tonic and surge release of LH in ovariectomized cows, and examine the dynamics of GnRH pulse release activity in response to known modulators of LH release (suckling, neuropeptide-Y [NPY]). In ovariectomized cows, both tonic release patterns and estradiol-induced surges of GnRH and LH were highly correlated. A 500-microgram dose of NPY caused an immediate cessation of LH pulses and decreased plasma concentrations of LH for at least 4 hours. This corresponded with a decrease in both GnRH pulse amplitude and frequency. In anestrous cows, GnRH pulse frequency did not change before and 48 to 54 hours after weaning on day 18 postpartum, but GnRH concentration and amplitudes of GnRH pulses increased in association with weaning and heightened secretion of LH. It is clear that high-frequency, highamplitude pulses of LH are accompanied by similar patterns of GnRH in CSF of adult cattle. Yet strong inhibitors of LH pulsatility, putatively acting at the level of the central nervous system (i.e., suckling) or at both the central nervous system and pituitary (NPY) levels, produced periods of discordance between GnRH and LH pulses.

Delayed diagnosis of cryptococcal meningoencephalitis due to negative cryptococcal antigen test

Cryptococcus spp. commonly causes infection in immunocompromised hosts. Clinical presentation of cryptococcal meningoencephalitis (CM) is variable, but headache, fever and a high intracranial pressure should suggest the diagnosis. The cryptococcal antigen test is a specific and sensitive rapid test that can be performed on blood or cerebrospinal fluid. We report a case of CM in a patient with previously undetected lymphocytopenia. Because cryptococcal antigen test results were negative, diagnosis and treatment were delayed.

Ataxia due to vertebral hemangiosarcoma with evidence of disseminated disease in a 20-year old Swiss Warmblood mare

A 20-year old Swiss Warmblood mare was referred to the Swiss Institute of Equine Medicine with a history of poor performance, coughing and ataxia and hindlimb weakness which progressed to recumbency. Lung auscultation revealed pronounced wheezing, blood work showed signs of chronic inflammation and increased bone turnover and thoracic ultrasound indicated patchy pulmonary consolidation. Cerebrospinal fluid revealed only mild, unspecific changes allowing exclusion of meningoencephalomyelitis and clinically relevant bleeding. Despite medical treatment and support in a sling the mare did not improve and was euthanized. Necropsy revealed a poorly demarcated, non-encapsulated and invasively growing mass dorsally in the musculature at the level of the forth cervical vertebra (C4) infiltrating the vertebral body and the spinal canal at the level of C1–C2. Multiple nodular, firm masses were present in all lobes of the lung and appeared to be mainly located in vessels. Histologically the masses were composed of spindle cells with marked anisocytosis, anisocaryosis, a high mitotic activity and showed invasive growth. These neoplastic cells stained positive for CD31, an endothelial cell marker, which confirmed diagnosis of a hemangiosarcoma. Definite ante mortem diagnosis of hemangiosarcoma, which is rare in horses, is challenging. Besides the vertebral localization, disseminated, locally invasive and cutaneous forms of hemangiosarcoma exist and can be either acquired or congenital. Prognosis for equine hemangiosarcoma and response to treatment are usually poor and progression of clinical signs is rapid. Vertebral hemangiosarcoma is an uncommon cause of spinal ataxia in horses.

Mixing-cell boundary conditions and apparent mass balance errors for advective-dispersive solute transport

In many field or laboratory situations, well-mixed reservoirs like, for instance, injection or detection wells and gas distribution or sampling chambers define boundaries of transport domains. Exchange of solutes or gases across such boundaries can occur through advective or diffusive processes. First we analyzed situations, where the inlet region consists of a well-mixed reservoir, in a systematic way by interpreting them in terms of injection type. Second, we discussed the mass balance errors that seem to appear in case of resident injections. Mixing cells (MC) can be coupled mathematically in different ways to a domain where advective-dispersive transport occurs: by assuming a continuous solute flux at the interface (flux injection, MC-FI), or by assuming a continuous resident concentration (resident injection). In the latter case, the flux leaving the mixing cell can be defined in two ways: either as the value when the interface is approached from the mixing-cell side (MC-RT -), or as the value when it is approached from the column side (MC-RT +). Solutions of these injection types with constant or-in one case-distance-dependent transport parameters were compared to each other as well as to a solution of a two-layer system, where the first layer was characterized by a large dispersion coefficient. These solutions differ mainly at small Peclet numbers. For most real situations, the model for resident injection MC-RI + is considered to be relevant. This type of injection was modeled with a constant or with an exponentially varying dispersion coefficient within the porous medium. A constant dispersion coefficient will be appropriate for gases because of the Eulerian nature of the usually dominating gaseous diffusion coefficient, whereas the asymptotically growing dispersion coefficient will be more appropriate for solutes due to the Lagrangian nature of mechanical dispersion, which evolves only with the fluid flow. Assuming a continuous resident concentration at the interface between a mixing cell and a column, as in case of the MC-RI + model, entails a flux discontinuity. This flux discontinuity arises inherently from the definition of a mixing cell: the mixing process is included in the balance equation, but does not appear in the description of the flux through the mixing cell. There, only convection appears because of the homogeneous concentration within the mixing cell. Thus, the solute flux through a mixing cell in close contact with a transport domain is generally underestimated. This leads to (apparent) mass balance errors, which are often reported for similar situations and erroneously used to judge the validity of such models. Finally, the mixing cell model MC-RI + defines a universal basis regarding the type of solute injection at a boundary. Depending on the mixing cell parameters, it represents, in its limits, flux as well as resident injections. (C) 1998 Elsevier Science B.V. All rights reserved.

CSF from Parkinson disease patients differentially affects cultured microglia and astrocytes.

BACKGROUND: Excessive and abnormal accumulation of alpha-synuclein (α-synuclein) is a factor contributing to pathogenic cell death in Parkinson's disease. The purpose of this study, based on earlier observations of Parkinson's disease cerebrospinal fluid (PD-CSF) initiated cell death, was to determine the effects of CSF from PD patients on the functionally different microglia and astrocyte glial cell lines. Microglia cells from human glioblastoma and astrocytes from fetal brain tissue were cultured, grown to confluence, treated with fixed concentrations of PD-CSF, non-PD disease control CSF, or control no-CSF medium, then photographed and fluorescently probed for α-synuclein content by deconvolution fluorescence microscopy. Outcome measures included manually counted cell growth patterns from day 1-8; α-synuclein density and distribution by antibody tagged 3D model stacked deconvoluted fluorescent imaging. RESULTS: After PD-CSF treatment, microglia growth was reduced extensively, and a non-confluent pattern with morphological changes developed, that was not evident in disease control CSF and no-CSF treated cultures. Astrocyte growth rates were similarly reduced by exposure to PD-CSF, but morphological changes were not consistently noted. PD-CSF treated microglia showed a significant increase in α-synuclein content by day 4 compared to other treatments (p ≤ 0.02). In microglia only, α-synuclein aggregated and redistributed to peri-nuclear locations. CONCLUSIONS: Cultured microglia and astrocytes are differentially affected by PD-CSF exposure compared to non-PD-CSF controls. PD-CSF dramatically impacts microglia cell growth, morphology, and α-synuclein deposition compared to astrocytes, supporting the hypothesis of cell specific susceptibility to PD-CSF toxicity.

Progressive multifocal leukoencephalopathy in a patient without apparent immunosuppression.

An 80-year-old man with no history of an immune-compromising disorder was diagnosed with progressive multifocal leukoencephalopathy (PML). He presented with dysphagia and left-sided weakness; magnetic resonance imaging demonstrated marked signal abnormality in the subcortical white matter of the left frontal lobe and in the posterior limb of the right internal capsule. Polymerase chain reaction (PCR) analysis of the cerebrospinal fluid (CSF) was negative for John Cunningham (JC) virus. On brain biopsy, foamy macrophages infiltrating the white matter were identified, staining positive for anti-simian virus 40 antibodies. Postoperatively, PCR for JC viral DNA in the CSF was positive, establishing the diagnosis of PML. Extensive investigation for an occult immunocompromising disorder was negative. The patient's neurologic deficits rapidly increased throughout his hospital stay, and he died 3.5 months after his diagnosis.

Transport of prion protein across the blood-brain barrier.

The cellular form of the prion protein (PrP(c)) is necessary for the development of prion diseases and is a highly conserved protein that may play a role in neuroprotection. PrP(c) is found in both blood and cerebrospinal fluid and is likely produced by both peripheral tissues and the central nervous system (CNS). Exchange of PrP(c) between the brain and peripheral tissues could have important pathophysiologic and therapeutic implications, but it is unknown whether PrP(c) can cross the blood-brain barrier (BBB). Here, we found that radioactively labeled PrP(c) crossed the BBB in both the brain-to-blood and blood-to-brain directions. PrP(c) was enzymatically stable in blood and in brain, was cleared by liver and kidney, and was sequestered by spleen and the cervical lymph nodes. Circulating PrP(c) entered all regions of the CNS, but uptake by the lumbar and cervical spinal cord, hypothalamus, thalamus, and striatum was particularly high. These results show that PrP(c) has bidirectional, saturable transport across the BBB and selectively targets some CNS regions. Such transport may play a role in PrP(c) function and prion replication.

Matrix metalloproteinase inhibition lowers mortality and brain injury in experimental pneumococcal meningitis

Pneumococcal meningitis (PM) results in high mortality rates and long-lasting neurological deficits. Hippocampal apoptosis and cortical necrosis are histopathological correlates of neurofunctional sequelae in rodent models and are frequently observed in autopsy studies of patients who die of PM. In experimental PM, inhibition of matrix metalloproteinases (MMPs) and/or tumor necrosis factor (TNF)-converting enzyme (TACE) has been shown to reduce brain injury and the associated impairment of neurocognitive function. However, none of the compounds evaluated in these studies entered clinical development. Here, we evaluated two second-generation MMP and TACE inhibitors with higher selectivity and improved oral availability. Ro 32-3555 (Trocade, cipemastat) preferentially inhibits collagenases (MMP-1, -8, and -13) and gelatinase B (MMP-9), while Ro 32-7315 is an efficient inhibitor of TACE. PM was induced in infant rats by the intracisternal injection of live Streptococcus pneumoniae. Ro 32-3555 and Ro 32-7315 were injected intraperitoneally, starting at 3 h postinfection. Antibiotic (ceftriaxone) therapy was initiated at 18 h postinfection, and clinical parameters (weight, clinical score, mortality rate) were recorded. Myeloperoxidase activities, concentrations of cytokines and chemokines, concentrations of MMP-2 and MMP-9, and collagen concentrations were measured in the cerebrospinal fluid. Animals were sacrificed at 42 h postinfection, and their brains were assessed by histomorphometry for hippocampal apoptosis and cortical necrosis. Both compounds, while exhibiting disparate MMP and TACE inhibitory profiles, decreased hippocampal apoptosis and cortical injury. Ro 32-3555 reduced mortality rates and cerebrospinal fluid TNF, interleukin-1β (IL-1β) and collagen levels, while Ro 32-7315 reduced weight loss and cerebrospinal fluid TNF and IL-6 levels.