AQP4 autoantibody assay performance in clinical laboratory service.

OBJECTIVE: To compare performance of contemporary aquaporin-4-immunoglobulin (Ig) G assays in clinical service. METHODS: Sera from neurologic patients (4 groups) and controls were tested initially by service ELISA (recombinant human aquaporin-4, M1 isoform) and then by cell-based fluorescence assays: fixed (CBA, M1-aquaporin-4, observer-scored) and live (fluorescence-activated cell sorting [FACS], M1 and M23 aquaporin-4 isoforms). Group 1: all Mayo Clinic patients tested from January to May 2012; group 2: consecutive aquaporin-4-IgG-positive patients from September 2011 (Mayo and non-Mayo); group 3: suspected ELISA false-negatives from 2011 to 2013 (physician-reported, high likelihood of neuromyelitis optica spectrum disorders [NMOSDs] clinically); group 4: suspected ELISA false-positives (physician-reported, not NMOSD clinically). RESULTS: Group 1 (n = 388): M1-FACS assay performed optimally (areas under the curves: M1 = 0.64; M23 = 0.57 [p = 0.02]). Group 2 (n = 30): NMOSD clinical diagnosis was confirmed by: M23-FACS, 24; M1-FACS, 23; M1-CBA, 20; and M1-ELISA, 18. Six results were suspected false-positive: M23-FACS, 2; M1-ELISA, 2; and M23-FACS, M1-FACS, and M1-CBA, 2. Group 3 (n = 31, suspected M1-ELISA false-negatives): results were positive for 5 sera: M1-FACS, 5; M23-FACS, 3; and M1-CBA, 2. Group 4 (n = 41, suspected M1-ELISA false-positives): all negative except 1 (positive only by M1-CBA). M1/M23-cotransfected cells expressing smaller membrane arrays of aquaporin-4 yielded fewer false- positive FACS results than M23-transfected cells. CONCLUSION: Aquaporin-4-transfected CBAs, particularly M1-FACS, perform optimally in aiding NMOSD serologic diagnosis. High-order arrays of M23-aquaporin-4 may yield false-positive results by binding IgG nonspecifically.

Leukoencephalopathy with spheroids (HDLS) and pigmentary leukodystrophy (POLD): a single entity?

Hereditary diffuse leukoencephalopathy with axonal spheroids (HDLS) and familial pigmentary orthochromatic leukodystrophy (POLD) present as adult-onset dementia with motor impairment and epilepsy. They are regarded as distinct diseases. We review data from the literature that support their being a single entity. Apart from a slightly older age at onset, a more rapid course, and more prominent pyramidal tract involvement, familial POLD is clinically similar to HDLS. Moreover, the pathologic hallmarks of the two diseases, axonal spheroids in HDLS and pigmented macrophages in POLD, can be identified in both conditions. This supports HDLS and POLD being referred collectively as adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP).

Hormonal influences in multiple sclerosis.

The function of hormones has expanded to include immunomodulation and neuroprotection in addition to their classic roles. The story of how hormones influence inflammation and neuron and glial function is being slowly unraveled. There is increasing evidence that estrogen, progesterone, and testosterone contain immune responses and influence damage repair in the nervous system. Hormones such as prolactin and vitamin D are being explored as immunomodulators and may influence diseases such as multiple sclerosis (MS) or may be used therapeutically to modulate the immune response. More recently identified hormones, such as leptin and gherlin, may also influence the course of disease. This chapter reviews some of the evidence that supports a role for hormones in MS.

Neuropsychological functioning in a patient with essential tremor with and without bilateral VIM stimulation.

The effects of deep brain stimulation on motor functions, cognitive abilities, and mood were assessed in an 80-year-old, right-handed male with a chronic history of essential tremor. Electrodes were implanted bilaterally in the ventral intermediate nucleus of the thalamus during a single operation. Upon evaluation at 3 months postsurgery, bilateral stimulation was associated with a clinically significant reduction in tremor ratings and improvement in manual dexterity. At that time, a battery of neuropsychological measures was administered with and without bilateral stimulation. The patient demonstrated comparable performances on measures of visuospatial perception, attention, mental tracking, verbal learning, and verbal recognition memory in both the "on" and "off" conditions. Without stimulation, the patient demonstrated declines of greater than 1 SD on measures of verbal fluency and verbal recall compared to when the stimulators were active. Responses to mood rating scales also indicated greater subjective distress without stimulation. Results are discussed in the context of previous studies of the effects of thalamic stimulation on neurocognitive functioning.

Intravascular lymphomatosis. A report of ten patients with central nervous system involvement and a review of the disease process.

The clinical, radiographic, and pathological findings in ten cases of intravascular lymphomatosis with central nervous system involvement seen at our institution over a 15-year period are presented. Nine patients presented with a subacute, progressive multifocal neurologic disorder. Most patients had fever, anemia, and elevation of the erythrocyte sedimentation rate. As the illness evolved, computerized tomography scanning and magnetic resonance imaging showed evidence of multifocal central nervous system disease. Angiography was nondiagnostic but suggested vasculitis in six cases. A response to empiric corticosteroid treatment was typical but usually transient. In six patients, the diagnosis was made antemortem by brain biopsy. The prognosis of patients was primarily dependent on early diagnosis and treatment, before massive central nervous system damage occurred. Treatment with chemotherapy, with or without radiotherapy, was associated with stabilization of the disease in three of five patients.

Pregnancy and multiple sclerosis.

In this review, we summarize the available information on the short- and long-term effects of pregnancy on the course of multiple sclerosis (MS). Published studies that used established criteria for the diagnosis of MS were given more weight than studies in which the criteria for diagnosis were unstated or unclear. Population-based studies were emphasized more than clinic-based studies, unless the clinic base was well defined and thought to be reasonably representative of the MS population in the geographic area. For completeness, small studies were also included but weighted accordingly in our overall conclusions. Methodologic limitations and biases inherent in the study methods are discussed. We conclude that patients with relapsing MS have an increased risk of relapse during the initial 6-month postpartum period. This increased risk does not seem to have a detrimental effect on the rate of developing sustained disability. In fact, a full-term pregnancy may increase the time interval to reaching a common disability endpoint-walking with the aid of a cane or crutch--or to having a secondarily progressive course. Evidence indicates that pregnancy may alter T-lymphocyte functions and cause clinically relevant consequences. The specific biochemical mechanisms responsible for these observations, however, remain undefined. Because of limitations of current knowledge, our conclusions are tentative at best. The data are most applicable to patients with relapsing-remitting MS in its early stages. MS is an unpredictable disease and is only one of many factors that patients must consider when a pregnancy is contemplated.

Epilepsy in women.

Physicians should be aware of certain gender-related issues in the treatment of women with epilepsy. Although in the past reproduction was discouraged in women with epilepsy, more than 90% of the pregnancies in such patients currently have an uneventful outcome with appropriate management. Oral contraceptive agents are not contraindicated in women with epilepsy; however, the contraceptive failure rate increases fourfold if patients are being treated concurrently with enzyme-inducing antiepileptic drugs. In pregnant patients, free drug levels of carbamazepine, phenobarbital, phenytoin, and valproate may change because of alterations in protein binding, clearance, and possible absorption. The dosage should be adjusted if the patient's seizures are increasing. Women with epilepsy may have disease-related or treatment-related menstrual dysfunction, complications of pregnancy (slightly increased risk of toxemia and fetal loss), endocrine dysfunction, appearance changes (a general coarsening of facial features with long-term administration of antiepileptic agents), and psychosocial maladjustment. Some effects are drug specific. Although control of seizures remains the primary goal of treating women with epilepsy, the widening choice of antiepileptic drugs may facilitate optimal management of secondary and gender-specific complications.

Seizures in pregnancy.

Seizures in pregnancy may risk the health of both mother and fetus. Epileptic women should ideally plan pregnancies after counseling by their primary care givers. New-onset seizures and any increase in seizure frequency or severity should be promptly evaluated. Eclampsia and status epilepticus represent life-threatening conditions that demand urgent multidisciplinary management.

Simultanagnosia as the initial sign of degenerative dementia.

In a study of 10 patients with degenerative brain disease that manifested as simultanagnosia, our aims were (1) to elucidate their clinical, neuropsychologic, and radiologic findings to determine whether these patients might represent a group distinguishable from those with typical Alzheimer's disease and (2) to help clinicians recognize this entity. All patients were initially examined by ophthalmologists because of visual difficulties, and the simultanagnosia remained undiagnosed until nonophthalmologic complaints developed. Optic ataxia developed in six patients, and all patients had mildly impaired eye movements. All 10 patients could identify colors appropriately. Nine patients had language deficits (anomia, decreased auditory comprehension, alexia, and agraphia) but were fluent and had relative preservation of sentence repetition, and four performed in the normal range on a test of associative fluency. Two patients scored in the normal range on memory tests, all had preserved insight, and nine had no family history of degenerative dementia. The mean age at onset of the disorder was 60 years (range, 50 to 69). Neuroimaging disclosed prominent bilateral occipitoparietal atrophy in nine patients and generalized atrophy in one. With this unusual but consistent clinical, neuropsychologic, and anatomic profile, these patients are clinically distinguishable from those with typical Alzheimer's disease, but until a specific cause has been found, we cannot be certain that they constitute a specific biologic entity. Clinicians should consider this diagnosis in relatively young patients who have slowly progressive nonocular visual complaints.

Monoclonal antibody for rapid laboratory detection of cytomegalovirus infections: characterization and diagnostic application.

Monoclonal antibodies to early (2H2.4, molecular weight 72,000 daltons) and late (2F3.0, molecular weight 68,000 daltons) antigens of the AD-169 strain of cytomegalovirus (CMV) were prepared by fusing mouse spleen cells with NS-1 mouse myeloma cells. The 2H2.4 monoclonal antibody produced a dense immunofluorescence with prominent lobular staining within the nucleus of CMV-infected substrate cells, whereas the reaction of 2F3.0 was more diffuse and generally involved the entire nucleus of the cells. Both monoclonal antibodies had little or no neutralizing activity against CMV in plaque-reduction assays. No cross-reactions were observed between these monoclonal antibodies and other members of the herpesvirus group. The 2H2.4 monoclonal antibody to early CMV antigen was used in a shell vial assay with a low-speed centrifugation step for the rapid (within 16 hours after inoculation) diagnosis of CMV infections. Optimal conditions for the test included centrifugation of shell vials at 700 X g for 45 minutes at 36 degrees C. An inoculum volume of 0.2 ml provided a reasonable balance between the optimal sensitivity for detecting specific viral fluorescence and the easy discrimination of the specific immunofluorescence from the background debris. Because of the commercial availability of the monoclonal antibody and the simplicity of the procedures used in the shell vial assay and subsequent fluorescence techniques, this rapid assay can be done in any laboratory that is familiar with cell culture manipulations.

Comparison of standard tube and shell vial cell culture techniques for the detection of cytomegalovirus in clinical specimens.

A monoclonal antibody was used to detect an early antigen of cytomegalovirus (CMV) by fluorescence 16 h after inoculation of MRC-5 monolayers in 1-dram (ca. 3.7-ml) shell vials and low-speed centrifugation. Of 770 specimens (urine, blood, lung tissue, sputum) processed in shell vials, 124 (16%) were positive for the virus at 16 h postinfection. CMV was isolated in standard tube cell cultures (average time, 9 days) from only 88 specimens, but there were no instances (with the exception of 2 blood specimens) in which CMV was recovered from tube cultures but not from shell vials. Additional specimens from 18 patients were positive in the shell vial assay but negative in the conventional tube cell culture assay. Other specimens from 14 of the 18 patients yielded CMV in conventional tube cell cultures. Of the 4 patients from whom CMV was not recovered from other specimens by conventional tube cell culturing, all had evidence of recent CMV infections, as indicated by a fourfold or greater rise in antibody titer. The specificity of the shell vial assay for the detection of CMV is supported by assays of other specimens from the same patients yielding the virus or serological evidence indicating recent infections, the known enhancement of CMV detection after centrifugation of the shell vials, and the distinct and easily recognizable fluorescence confined to the nuclei of CMV-infected cells. Our data indicate that the shell vial cell culture assay for the detection of CMV is as specific as and more sensitive than conventional tube cell culturing for the diagnosis of CMV infections.

Rapid detection of cytomegalovirus in MRC-5 cells inoculated with urine specimens by using low-speed centrifugation and monoclonal antibody to an early antigen.

A commercially available monoclonal antibody directed against an early nuclear protein of cytomegalovirus was used with low-speed centrifugation for the rapid detection of this virus from urine specimens inoculated onto MRC-5 cells. A total of 19 of 162 (11.7%) urine specimens inoculated were positive by both immunofluorescence and peroxidase-antiperoxidase procedures (sensitivity, 100%), whereas only 18 of the samples produced cytopathic effects in conventional cell culture (specificity, 94.7%). All specimens were positive by immunofluorescence and peroxidase-antiperoxidase procedures at 36 h postinfection, whereas an average of 9 days was required for cytopathic effects to develop in cell cultures.