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PubMed1994

Laboratory evaluations in HIV-1-associated cognitive/motor complex.

Laboratory tests can provide useful information about the presence and effects of HIV-1 in the CNS, but have thus far not yielded definitive diagnostic or prognostic markers of HIV-1-related cognitive and motor complex. The most clinically useful laboratory procedures are MR imaging and CSF examinations. The routine clinical use of MR imaging and CSF examinations, however, is still restricted to providing information for detecting and excluding secondary effects of HIV-1 infection. MR imaging and CT do not appear to be sensitive enough at current resolutions to provide early detection of HIV-1 CNS effects nor to follow disease progression. Several CSF variables are extremely promising as early markers of primary HIV-1 infection of the brain, and may provide preclinical indications for onset of treatment and for evaluation of treatment efficacy. These include CSF quinolinic acid levels, acid dissociated p24 antigen levels, neopterin or beta 2m, intrathecal IgG synthesis rate, and possibly quantitated PCR levels of HIV-1 viral load. Procedures such as nuclear magnetic resonance spectroscopy, SPECT, PET, computerized EEG, EP, and ERPs are all promising candidates for early detection or localization of HIV-1-related brain dysfunction, but at this time all must still be considered primarily research tools. Before any of these procedures can provide reliable diagnostic and prognostic information about primary HIV-1 neurologic disease, currently on-going longitudinal evaluations of large numbers of asymptomatic HIV-1-infected individuals as they progress to neurologically symptomatic disease must be completed. There is currently no laboratory marker in blood or CSF that definitively predicts the risk for HIV-1-associated cognitive/motor complex. HIV-1-associated cognitive/motor complex remains a clinical diagnosis, which is made on the basis of positive neurologic signs and symptoms and abnormal neuropsychological findings after other causes of neurologic disease are excluded. Laboratory measures, such as the electrophysiologic methods and some CSF variables, are likely to remain adjuncts to the diagnosis because, with few exceptions, they provide data that are nonspecific as to etiopathogenesis. Dynamic imaging, electrophysiologic methods, and CSF indices provide presumptive evidence for the presence of HIV-1-associated CNS damage, and with clinical and neuropsychological evidence, could be used to establish a new definition of primary HIV-1-associated CNS disease along the lines used in establishing a diagnosis of multiple sclerosis.(ABSTRACT TRUNCATED AT 400 WORDS)

AIDS Dementia Complex↗
PubMed2003

Heat insoluble cryoglobulin associated with gangrene in multiple myeloma.

Cryoglobulins are immunoglobulins that have tendency to precipitate in temperatures below 37 degrees C and dissolve with rewarming. Monoclonal cryoglobulins are usually associated with a distinct hematological disorder and often are asymptomatic. Heat insoluble cryoglobulin has been described with Sjogren's syndrome and glomerulonephritis but, not with multiple myeloma. Severe sensitivity to cold occurs with high thermal insolubility of the cryoprotein, with dramatic symptoms when exposed to minimal lowering of the temperature. We report a case of a 49 year old man with multiple myeloma and an unusual type I cryoglobulin that caused occlusive gangrene. The cryoglobulin appeared as a milky white precipitate that was resistant to re-suspension and did not dissolve at 37 degrees C. Immunoelectrophoresis of the cryoglobulin, which dissolved at 56 degrees C, showed it to be composed of a monoclonal IgG kappa protein (3.5 g/dl). Unlike most high thermal insoluble cryoglobulin, cold associated symptoms were not seen. In addition to steroids, plasmapheresis was initiated thrice a week with albumin fluid replacement. Plasmapheresis caused a marked decline in cryocrit levels from 21% to less than 0.5% in 9 days after 4 procedures with resolution of the gangrene of the feet and after 6 treatments, vasculitic symptoms improved dramatically. The cryoglobulin test was negative 2 weeks after initiation of treatment. The patient was treated for the myeloma and there was no recurrence of occlusive symptoms. Proper laboratory procedure and careful examination and handling of cryoglobulinemic samples facilitate detection of unusual cryoglobulins. This is a unique report of multiple myeloma with gangrene of lower extremities that has a heat insoluble cryoglobulin.

Cryoglobulinemia↗
PubMed1989

The measurement of anti-DNA activity in the sera of patients with systemic lupus erythematosus: theoretical and practical considerations.

Measurement of anti-DNA antibody activity has become a routine laboratory procedure of value in diagnosing and managing patients with systemic lupus erythematosus. However, there is no agreement as to the most suitable technique that should be employed. In this review, currently available assay procedures are critically evaluated with particular emphasis on accuracy, simplicity, reproducibility and ease of standardisation. The nitrocellulose filter technique appears to possess most of these qualities and is recommended as the standard assay for the measurement of anti-DNA activity in the clinical laboratory.

Antibodies, Antinuclear↗
PubMed1991

The laboratory diagnosis of Lyme disease.

Growing awareness of Lyme disease, caused by the tickborne spirochete Borrelia burgdorferi has led to a marked increase in laboratory procedures to help in its diagnosis. Despite the frequent ordering of serologic tests specific for Lyme disease, there remains confusion in the accurate interpretation of these tests. Because of the important cutaneous manifestations of B burgdorferi infection, dermatologists should understand the role of the laboratory in Borrelia-related conditions. This article reviews laboratory techniques available for the diagnosis of Lyme disease. The role of histologic findings and culture, the sensitivity, specificity, and reproducibility of commonly used serologic tests, the effects of disease duration and treatment on serologic results, and the future of laboratory diagnosis are described.

False Positive Reactions↗
PubMed1981

Precision of "high-performance" liquid-chromatographic assays with sample pretreatment. Error analysis for the Technicon "FAST-LC" system.

A comprehensive theory has been presented elsewhere (Anal. Chem. 53: 877-884, 1981) for the various contributions to assay imprecision in procedures that are based on sample extraction followed by "high-performance" liquid chromatography. Experimental data (1800 assays, 8400 results) for the Technicon FAST-LC system are used with this theory in an effort to understand and control the precision of clinical-laboratory procedures, both automated and manual. This study provides specific conclusions and recommendations on matters such as: standardization procedures and protocols, physical properties requires in internal standards, the relative importance of different sources of imprecision and means for improving precision, the relative importance of temperature control in pretreatment and liquid-chromatographic analysis, and the precision obtainable with small sample volumes or with samples containing very low concentrations of analyte (e.g., in assays for free drugs). Automation evidently can lead to twofold greater assay precision, other factors being equal, for liquid-chromatographic procedures that include sample pretreatment. Similarly, internal standardization, properly applied, can decrease assay imprecision by twofold.

Anticonvulsants↗
PubMed1976

A rapid testing procedure to determine low levels of ocular irritation.

A new and rapid method for testing low levels of ocular irritation using a balanced incomplete block design, a new grading system, and statistical analysis of the results, has been developed. Two drops (0.1 ml) of 1 of 5 ophthalmic solutions were instilled into the conjunctival sac of the right or left eye of each of 10 New Zealand white [Deb:(NZW)] rabbits hourly for 9 hr on 4 consecutive da. Before the study and before the first instillation on each day, the eyes were examined with a direct ophthalmoscope, and the reactions were graded according to a modification of the system in the illustrated Guide for Grading Eye Irritation by Hazardous Substances. The new procedure showed that 1 of the 5 solutions elicited a significantly more severe (p less than or equal to 0.05) ocular response of redness, chemosis, and discharge than did any of the other 4 solutions. Previous testing of this solution in rabbits by standard laboratory procedures and the Draize method of grading ocular irritation failed to detect these reactions.

Animals↗
PubMed1978

Evaluation of the counterimmunoelectrophoretic (CIE) procedure in a clinical laboratory setting.

The counterimmunoelectrophoretic (CIE) procedure was evaluated under clinical laboratory conditions to determine its validity and comparability with culture methods. The procedure was further evaluated to determine applicability to a variety of clinical samples. An inexpensive set-up was developed to utilize the CIE procedure at bench level. Results indicated the procedure to be sensitive in detecting Haemophilus influenzae, type b, and Neisseria meningitidis (meningococcus), group B. The procedure was more sensitive for detection of H. influenzae, type b, than for meningococcus, group B. The authors have confirmed the usefulness of the CIE procedure in the detection of group B streptococci, pneumococci and teichoic acid antibody to Staphylococcus aureus. Detection of Escherichia coli K 1 antigen was also accomplished by CIE. In the authors' laboratory the CIE procedure was superior to culture methods when used for the detection of H. influenzae, type b, and meningococcus group B.

Animals↗
PubMed2006

Improvement of real-time polymerase chain reaction for quantifying TNF-alpha mRNA expression in inflamed colorectal mucosa: an approach to optimize procedures for clinical use.

OBJECTIVE: The precise measurement of local tumor necrosis factor alpha (TNF-alpha) expression in tissue is important in understanding the pathogenesis of inflammatory bowel diseases (IBD). Real-time polymerase chain reaction (PCR) is a sensitive, versatile method and is becoming a commonly used tool for the quantification of gene expression. The aim of this study was to optimize the laboratory procedure for biopsy sampling, storage and calibration of result for TNF-alpha mRNA quantification with real-time PCR of colorectal biopsies. MATERIAL AND METHODS: Endoscopic biopsies from the colorectum were obtained from 18 patients with ulcerative colitis (UC), 11 patients with Crohn's disease (CD) and 18 normal controls. Optimization of procedures for real-time PCR performance was carried out. RESULTS: The transport medium, RNAlater, exhibited a high preservation effect against RNA degradation even after 8 days of storage at room temperature; one biopsy from each patient was sufficient for RNA extraction, cDNA synthesis and TNF-mRNA quantification. An assay was established with a technical reproducible sensitivity of 100 copies/microL. The observed interassay variations were 7.4 % coefficient of variation (CV) and 7.2 % CV in low and high TNF-alpha mRNA expression biopsies, respectively. TNF-alpha mRNA levels in colorectal biopsies from patients with either CD or moderate to severe UC were markedly increased, and 8 approximately 9-fold higher than those in healthy controls. CONCLUSIONS: This optimization improves the clinical use of real-time PCR for quantification of TNF-alpha gene expression in colorectal biopsies and provides a sensitive reproducible assay.

Adult↗
PubMed1988

Using the microbiology laboratory in the diagnosis of pneumonia.

Pneumonia/influenza is one of the top ten leading causes of mortality in the United States each year. The identification of the etiologic agent responsible for lower respiratory tract infection plays an important role in the proper management of this clinical problem. The specimens submitted for evaluation are obtained in diverse ways and include expectorated sputum, material from transtracheal and bronchoscopic procedures, pleural fluid and lung aspirates, and biopsy of actual lung tissue. Processing of material can include stained smears, aerobic and anaerobic cultures, and special processing techniques for fungal, viral, Pneumocystis carinii, Legionella, mycobacterial, and mycoplasma identification. Modifications of smear preparation techniques and application of the new DNA probe technology are providing the opportunity for rapid microbiologic testing of clinical specimens with increased sensitivity and specificity, often obviating the need for invasive diagnostic procedures. Laboratory methodology is continually undergoing technological change, and optimal care of the patient with pneumonia requires close cooperation between the attending physician and the clinical laboratory.

Bacteriological Techniques↗
PubMed1998

A new fully adjustable articulator system and procedure.

This article presents a simple and efficient articulator to help with the registration of maxillomandibular relationships, mounting casts, and subsequent perfection of the occlusal scheme for various types of prosthodontic restorations. The system (Individual Anatomo-Physiological system), which is composed of the articulator and recommended procedures, allows for registration of positions and trajectories of the mandible at the level of the patient's occlusal plane. It is used to accurately transfer the records to the articulator. A luminous signal shows the correct centric occlusal relationship and vertical dimension, in both clinical and laboratory procedures. Interocclusal records are used for semiadjustment of the articulator for provisional restorations and stereographic records are used for full adjustment of the articulator for definitive treatment.

Dental Articulators↗
PubMed2004

A surgical stent for the Brånemark Novum bone reduction procedure.

BACKGROUND: The Brånemark Novum concept (Nobel Biocare AB, Göteborg, Sweden) was introduced to load implants immediately with a definitive fixed prosthesis in the edentulous mandible. This concept is based on the use of prefabricated templates to allow precise placement of three implants and a prefabricated bar structure for the prosthetic procedure. To obtain three-dimensional stability in these prefabricated templates, surgical bone reduction may be necessary to obtain a stable adaptation between the templates and the recipient bone site. PURPOSE: The aim of this work was to design a surgical stent for predictable reduction of the residual alveolar crest prior to the implant placement procedures. MATERIALS AND METHODS: A predetermined alveolar crest platform based essentially on a lateral cephalometric radiographic evaluation was simulated on a cast in order to design a transparent resin surgical guide. The predictability potential of the procedure was then evaluated in 10 patients. The prosthetic outcomes were compared with those of a similar group of 10 patients treated without the presented stent by evaluating two factors, namely, the anterior dimensions of the prostheses and the required posterior adjustments of the upper bar. RESULTS: Correlation analysis of our series suggested a good predictability potential for this procedure (r = 0.9215). The mean anterior prosthetic dimension was 32% lower and was more predictable (narrow range of 8-12 mm vs broad range of 8-21 mm) when the stent was used. Furthermore, since half as many posterior adjustments of the upper bar were required, the laboratory procedure was facilitated. CONCLUSION: This individualized guide allows appropriate bone reduction for obtaining a predictable surgery and prosthetic stage.

Adult↗
PubMed1977

Primary deficiencies in humoral immunity.

Patients with primary disorders of B lymphocytes and immunoglobulins usually display increased susceptibility to bacterial infections but atopic, autoimmune, and malignant disorders are also more common in these patients. The spectrum of these disorders ranges from a virtual absence of B cells and immunoglobulins to selective deficiencies of immunoglobulin subclasses. The diagnosis is dependent upon the demonstration of the immunologic deficits by specialized laboratory procedures which include the quantitation of immunoglobulins, the formation of antibodies in vivo and in vitro and the demonstration of B cells in the tissues or the peripheral blood. There are five major points in the management of these patients: (1) the delineation of the immunologic defects by laboratory testing, (2) the use of parenterally injected human immunoglobulins, (3) the rapid identification of infecting organisms and the prompt institution of appropriate antibiotic therapy, (4) screening the family for immunodeficiency in those cases which are of genetic origin, and (5) genetic counseling.

Adult↗
PubMed2002

Orthopaedic surgery in severe bleeding disorders: a low-volume, high-cost procedure.

As more and more nations are scrutinizing their health care costs, attention has been focused on high-cost low-density disease. Assessment of actual total cost of care for haemophilia and its positive outcome becomes essential to justify support for these patients. In this study, we assessed hospital cost and diagnosis-related group (DRG) reimbursement for patients undergoing elective orthopaedic surgical procedures from May 1999 to December 1999. Hospital cost was assessed by a prospective microcost-analysis method. To identify real hospital costs, we performed registration of preoperative phase, operative phase and 1-year follow-up costs. Hospital cost included personnel costs and costs for clinical and laboratory procedures, blood products, prosthetic implants, coagulation factor concentrates and drugs. These data were compared with hospital DRG reimbursement. We included nine consecutive patients, with a mean age 38 years (19-54 years) who had had 10 major orthopaedic surgical procedures performed during the study period. Six patients had haemophilia A, two had haemophilia B and one had factor VII deficiency. Data analysis showed a mean cost of US$ 54,201 (range US$ 25,795-105,479; 1US$ = 8.5 NOK). The average actual hospital revenue (50% DRG reimbursement + income related to length of stay) was $4,730 (range $ 1,308-13,601). Our study confirms that orthopaedic surgery in patients with severe bleeding disorders puts the hospital to a considerable expense. Activity-based financing, as used in Norway, does not provide a proper reimbursement for this part of the haemophilia care.

Adult↗
PubMed2004

Essential issues of laboratory investigation for patients with haemophilia and bleeding disorders.

Apart from history-taking and physical examination, laboratory investigation is one of the essential issues for the definite diagnosis of haemophilia and bleeding disorders. The limited resources of medical personnel, equipment and reagents should be shared among several departments in the hospital, especially for serving patients with common genetic diseases such as thalassemia and haemoglobinopathies. Medical personnel require appropriate training to expand their skills in laboratory techniques. Laboratory procedures can be created, modified and simplified using locally produced and shared equipment. Molecular genetic studies can also be set up at different levels of hospital service using simple, rapid and low-cost methods. Finally, a system of periodic external quality control will guarantee the accuracy of laboratory results.

Blood Coagulation Disorders↗
PubMed2002

Prenatal screening tests facilitate risk assessment.

Medical technology continues to improve services and testing to provide accurate and timely information for physicians and patients. New screening protocols in which information obtained in the first and second trimesters is integrated to improve detection and lower false positive rates have potential for safer and more effective prenatal care. Families still have difficult choices to make when confronted with the diagnosis of a birth defect. Inherent advantages of early detection are reassurance for low-risk women sooner, and for women with increased risk, more time to consider all options. Without doubt, improvements in risk assessment, diagnosis, and prevention will continue. The advantage offered by laboratory procedures is that the preliminary diagnosis can be made by simple, noninvasive screening tests.

Adult↗
PubMed1980

Nutritionally deficient Streptococcus: investigation of the hidden culprit in culture-negative endocarditis.

Subacute bacterial endocarditis in a 72-year-old woman was found to be caused by nutritionally deficient ("satelliting") Streptococcus sanguis. The organism, which required pyridoxal compounds or thiol substitutes, was identified after the application of relatively unusual but simple laboratory procedures. Normally, the organism's nutritional requirements would be fulfilled by components of the human blood that are used to inoculate clinical blood cultures, provided that the dilutional effect of the media is less than 10. The difficulty of diagnosis in such cases appears to lie in the laboratory inability to identify the organisms, rather than in failure to grow in properly obtained blood cultures.

Aged↗
PubMed1992

Fast one-step procedure for the detection of nucleic acids in situ by primer-induced sequence-specific labeling with fluorescein-12-dUTP.

We provide fast, simple, one-step procedures for sequence-specific detection of nucleic acids in situ. Tandem repeat sequences in DNA are stained within 30 min, and mRNA is stained within 2 h. The procedures are based on the incorporation of the newly available fluorescein-labeled dUTP into DNA synthesized in situ by primed in situ labeling, with denatured fragments of cloned DNA or oligonucleotides as primers. The extreme speed and simplicity of the reaction make it attractive for automatization in routine laboratory procedures and opens up new diagnostic possibilities.

DNA↗
PubMed1999

Identification of IgG-specific oligoclonal banding in serum and cerebrospinal fluid by isoelectric focusing: description of a simplified method for the diagnosis of neurological disorders.

Clinical laboratory procedures using cerebrospinal fluid (CSF) to assist in the diagnosis of multiple sclerosis (MS) are based essentially on the determination of oligoclonal bands (OB) in CSF and not in serum. To date, the techniques using isoelectric focusing (IEF) have represented one of the most efficient methods for detecting supernumerary bands in CSF but unfortunately were not always compatible with a routine use. Here, we describe a revised method of IEF suitable for the diagnosis of neurological disorders. The kit-based technique was simplified and the present procedure allowed an easier execution, reduced the overall analysis time and permitted an uncomplicated intepretation of oligoclonal profiles. Moreover, the technique developed was very sensitive and specific for the diagnosis of MS diagnosis. In conclusion, the IEF protocol described in this report is suitable for OB detection in any laboratory.

Central Nervous System Diseases↗