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Role of the laboratory in management of acute and chronic renal failure.

The initial assessment and differential diagnosis of acute renal failure is greatly facilitated by laboratory procedures of varying sensitivity and specificity; these are reviewed in detail. Patients with chronic renal failure receiving maintenance dialysis exhibit many laboratory abnormalities which may differ significantly between patients treated with hemodialysis and those receiving peritoneal dialysis. These are also reviewed.

Acute Kidney Injury↗

Circumscribed intestinal protein loss with deficiency in CD4+ lymphocytes after the Fontan procedure.

UNLABELLED: Protein-losing enteropathy is an important complication after right heart bypass operations (Fontan procedure). Laboratory examinations usually reveal hypoalbuminaemia, hypoproteinaemia, elevated alpha(1)-antitrypsin clearance, and lymphocytopenia. A case of protein-losing enteropathy after Fontan procedure is reported with a circumscribed protein loss in the region of the terminal ileum despite good haemodynamics. The patient developed only mild hypoalbuminaemia and no diarrhoea but severe cellular and humoral immune abnormalities, namely a markedly decreased proportion of CD4+ lymphocytes but normal proportion of CD8+ lymphocytes (CD4+ 14%, CD8+ 23%) and decreased serum levels of immunoglobulin G. Intestinal biopsies revealed normal mucosa. This report is unique as it is the first to describe a ratio of CD4+ to CD8+ lymphocytes <1 due to an almost selective loss of CD4+ lymphocytes and a circumscribed intestinal protein loss in a patient who developed protein-losing enteropathy after Fontan operation. CONCLUSION: There is a severe decrease of CD4+ lymphocytes of unknown origin in a patient with circumscribed intestinal protein loss after Fontan operation. Passive leakage of lymph fluid due to abnormal systemic venous pressure is not a sufficient explanation of the almost selective loss of CD4+ lymphocytes. Primary or secondary activation of the immune system may influence structural integrity and permeability of the intestinal wall and may play a triggering role in protein-losing enteropathy after the Fontan procedure.

CD4 Lymphocyte Count↗

[Postgraduates' training as laboratory physicians/clinical pathologists in Japan--board certification of JSLM as a mandatory requirement for chairpersons of laboratory medicine].

The educational committee of the Japanese Society of Laboratory Medicine(JSLM) proposed a revised laboratory medicine residency curriculum in 1999 and again in 2001. The committee believes that present undergraduate clinical training is insufficient and that Japanese medical graduates need clinical training for two years after graduation. This two years training should be a precondition for further postgraduate training in laboratory medicine and should include fundamental clinical skills(communication skills, physical examination and common laboratory procedures such as Gram's stain, Wright-Giemsa stain and urinalysis). After the two years training, the minimal training period of laboratory medicine should be three years, and should include: 1) Principles, instrumentation and techniques of each discipline including clinical chemistry, clinical hematology, clinical microbiology, clinical immunology, blood banking and other specific areas. 2) The use of laboratory information in a medical setting. 3) Interaction of the laboratory physician with laboratory staff, physicians and patients. With good on-the-job training and 24 hours on-call duties, laboratory physicians are expected to perform their tasks, including laboratory management, effectively. They should have appropriate educational background and should be well motivated. The background and duties of the laboratory physicians often reflect the institutional needs and personal philosophy of the chairperson of their department. At the moment, few senior physicians in Japan have qualifications in laboratory medicine and are unable, therefore, to provide the necessary guidance to help the laboratory physicians in their work. I therefore believe that the board certification of JSLM should be regarded as mandatory for chairpersons of laboratory medicine. Our on-call service system can enhance the training in laboratory medicine, and improve not only laboratory quality assurance but patients' care as well.

Certification↗

From serological to computer cross-matching in nine hospitals.

In 1991 it was decided to reorganise the transfusion service of the County of Funen. The aims were to standardise and improve the quality of blood components, laboratory procedures and the transfusion service and to reduce the number of outdated blood units. Part of the efficiency gains was reinvested in a dedicated computer system making it possible--among other things--to change the cross-match procedures from serological to computer cross-matching according to the ABCD-concept. This communication describes how this transition was performed in terms of laboratory techniques, education of personnel as well as implementation of the computer system and indicates the results obtained. The Funen Transfusion Service has by now performed more than 100.000 red cell transfusions based on ABCD-cross-matching and has not encountered any problems. Major results are the significant reductions of cross-match procedures, blood grouping as well as the number of outdated blood components.

Blood Banks↗

[Risk of exposure to UV radiation at biochemical laboratories].

In biological and chemical laboratories UV radiation is largely used, particularly in photo biological and photochemical studies, with the objective to sterilize or to visualize the samples in different technical analysis. In this work we present the results of the evaluation of UV exposition levels and the hazards for researchers and students, that the results shows elevated if they don't use correct laboratory procedures and protective wear.

Biochemical Phenomena↗

Recommendations for quality improvement in genetic testing for cystic fibrosis. European Concerted Action on Cystic Fibrosis.

These recommendations for quality improvement of cystic fibrosis genetic diagnostic testing provide general guidelines for the molecular genetic testing of cystic fibrosis in patients/individuals. General strategies for testing as well as guidelines for laboratory procedures, internal and external quality assurance, and for reporting the results, including the requirements of minimal services in mutation testing, the nomenclature for describing mutations, procedures to control false-positive amplification reactions and to validate tests, and guidelines to implement a quality system in a molecular diagnostic laboratory are reviewed.

Accreditation↗

Analytical methods for the determination of the molluscicide N-tritylmorpholine in water.

A colorimetric method has been developed for the determination of the molluscicide N-tritylmorpholine (Frescon, WL 8008) in water. The method is based on the production, from N-tritylmorpholine in strong acid, of the typical yellow colour of the tritylcarbonium ion.Two procedures are recommended for field use, neither of which distinguishes between N-tritylmorpholine and its hydrolysis product triphenylcarbinol (triphenylmethanol). A more precise laboratory procedure is described, by means of which both N-tritylmorpholine and triphenylcarbinol can be determined separately.

Colorimetry↗

A conservative procedure for the diagnosis of catheter-related infections.

A prospective study was done in 139 intravascular catheters (IVCs) that had been removed for different reasons. The purpose of the study was to compare laboratory procedures for the diagnosis of catheter-related infections and also to attempt to clarify the present controversy regarding the portal of entry of such infections. The IVCs were removed by one of us and multiple samples were studied according to a standard procedure. Semi-quantitative cultures were performed of the tips, the interior of the hub, and the skin around the insertion point. Quantitative cultures were performed of the infusion fluid and of the IVC tips. Of the 139 IVCs studied, 53 (38.1%) were infected (greater than or equal to 15 colony-forming units per plate in the semiquantitative culture). Semi-quantitative and quantitative cultures gave comparable results, but the semiquantitative procedure proved to be easier and faster. All but three infected catheters had a positive (greater than or equal to 15 colony-forming units per plate) skin and/or hub culture (superficial cultures), with microorganisms identical to those isolated in the IVC tip. Our results showed two possible and differentiable portals of entry. Thirty (56.6%) had external origin (semiquantitative skin culture positive), 12 (22.6%) had an internal origin (semiquantitative hub culture positive), and 8 (15.1%) had both origins. All catheters with negative superficial cultures had a negative tip. The predictive value of positive superficial cultures in the diagnosis of catheter-related infection was 66.2% and that of negative cultures was 96.7%. In patients with suspected catheter-related infections but negative superficial cultures, the possibility of infection may reasonably be ruled out, thereby avoiding many unnecessary catheter withdrawals.

Adolescent↗

[Preparation of human semen for in vitro fertilization procedures and intra-fallopian gamete transfer].

Techniques of "In Vitro" fertilization (IFV) and gamete intrafallopian transfer (GIFT) are proving to be successful in the treatment of infertility. We report here in detail the laboratory procedures of sperm processing for these two techniques also in the present work we pointing out the media quality control methods and the incubation time for the maintenance of spermatozoa fertilizing ability.

Female↗

Conversion of an interim into a definitive speech aid: a predictable approach.

In patients with partial or total soft palatectomy, an interim prosthesis generally is inserted as soon as possible after surgery. Over the average postoperative healing period of 3 months, numerous clinical appointments are needed to shape the prosthesis. When the definitive prosthesis is completed, reshaping the pharyngeal portion of the speech aid unnecessarily involves duplication of work by the clinician. A laboratory procedure is described that can save clinic time, increase cost-effectiveness, and shift work normally performed by the maxillofacial prosthodontist to the maxillofacial laboratory technician. This technique is particularly useful with prostheses that are difficult to shape because of trismus or lack of residual lateral and posterior pharyngeal movement.

Cost-Benefit Analysis↗

Laboratory tests for rapid screening of drugs of abuse in the workplace: a review.

The use of rapid, on-site drug detection devices is reviewed. These tests permit the detection of various psychoactive substances in urine, and are easily used by nonskilled personnel. Saliva tests are available for detection of alcohol. These rapid tests have varying degrees of accuracy, and it is recommended that positive outcomes for all rapid tests be verified by standard laboratory procedures. The tests have potential use in the emergency room, doctor's office, drug treatment program, and the work place. When access to formal laboratory testing is limited by either time or location, an easily portable test can give critical information. A number of commercially available tests are reviewed for method, accuracy, advantages and disadvantages. Consequently, the interested practitioner should be able to find a suitable screening test from among the tests reviewed.

Humans↗

Accurate procedure for simultaneous registration of gingival emergence profile and maximal intercuspal position for metal ceramic restorations.

This article describes a procedure that simultaneously registers maximal intercuspal position and gingival emergence profile. The materials used in this procedure are inexpensive, readily available, and easy to use. The clinician can inspect the framework, cast, and tissue profile before sending them to the laboratory. When this method is properly used, it allows better communication with the dental technician, saves chair time, and reduces the number of laboratory procedures as currently practiced.

Acrylic Resins↗

Control of streptococcal throat infections in schools; a cooperative program followed in Orange County.

Attempts to identify streptococcal throat infections on clinical evidence alone do not provide an adequate or reliable index of the prevalence of these infections in the community. Epidemiologic information on streptococcal throat infections based on bacteriological identification permits a more accurate assessment of the situation and more logical and more effective control measures. Recent refinements in laboratory procedures have provided a simple, reliable and relatively inexpensive method for the identification of Group A beta hemolytic streptococci by public health or clinical laboratories. In Orange County a program for the identification of streptococcal throat infections by cooperative action of the medical profession, the health department and the school authorities greatly aided in control of the disease. A voluntary health agency (heart association) made an important contribution toward the success of the control program.

Acute Disease↗

[Analysis of the results of bronchoalveolar lavage (BALF) in patients with pulmonary sarcoidosis].

Bronchoalveolar lavage is a relatively new method in pulmonology. Treatment of broncho-alveolar fluid-washing/BALF/obtained after the procedure of broncho-alveolar lavage/BAL/enables obtaining of samples for investigation of inflammatory and immune cells, so-called alveolar, which, treated by different laboratory procedures, represent the source for different informations at many lung diseases. Analysis of BALF is significant in the differential diagnosis of interstitial lung changes, in the estimate of process activity as well in analysis of therapy with glucocorticosteroids, as well as in the estimate of immune cells state, particularly T abd B lymphocyte subpopulations. We have analysed BALF in 161 patients with lung sarcoidosis with the purpose of analysing the process activity and according to activity of lymphocyte alveolitis in relation to total lymphocyte number in BALF cytogram and by identification of T and B lymphocytes and their subpopulations/CD4, CD8, CD11/as well as by the index CD4/CD8. We have determined the CD4, CD8, CD11 values as well as B lymphocytes by monoclonal antibodies, manufactured by ORTHO-mune/USA/, signed by the manufacturer as OKT4, OKT8, OKT11, OKT22, conjugated by gost antimice IgG antibodies. The working procedure we have done according to instructions of the manufacturer by immunofluorescent technic.

Adolescent↗

Matrix effects on proficiency testing materials. Impact on accuracy of cholesterol measurement in laboratories in the nation's largest hospital system.

The objective of this collaborative study with the Department of Veterans Affairs (VA), College of American Pathologists (CAP), and the Centers for Disease Control and Prevention (CDC) was to quantitate the matrix-induced biases of cholesterol measurements on the CAP Comprehensive Chemistry Surveys materials used in proficiency testing (PT). A total of 174 VA Medical Centers outpatient clinics and clinical laboratories participate in the VA-CDC National Cholesterol Standardization and Certification Program. This study was conducted in 112 VA laboratories that have been standardized for measuring cholesterol accurately (within +/- 3.0% of the CDC reference-method values) using fresh, unfrozen, unadulterated human serum samples. Fresh serum samples and 1990 CAP Surveys materials were sent by overnight mail, and the laboratories were asked to analyze them simultaneously in triplicate in a single analytic batch run. The results showed significant matrix-effect biases with the CAP Surveys materials with six of the eight major peer groups, despite the fact that accuracy of cholesterol measurements was maintained with fresh serum samples. The magnitude and direction (positive or negative) of the matrix-effect biases were instrument, reagent, and method specific using the following peer groups: du Pont Dimension (-8.9%); Beckman CX4, CX5, and CX7 (-5.5%); Kodak Ektachem 400, 500, and 700 (+4.4%); Instrumentation Laboratory Monarch (-3.1%); Baxter Paramax (-2.4%); Technicon SMAC and RA (+1.3%); Hitachi/BMD 704 through 747 (+0.4%); and Abbott Spectrum (-0.3%). The CAP PT materials used currently do not behave in a manner identical to fresh human serum when measuring cholesterol on many, but not all, analytic systems. The observed biases due to "matrix effects" with PT materials will cause incorrect conclusions about the accuracy of many laboratory procedures performed on fresh patient specimens. This matrix-effect phenomenon will severely hamper interlaboratory accuracy transfer, standardization efforts, and monitoring performance of a laboratory's testing accuracy with the use of the current survey materials used in PT programs. Collaborative efforts are needed to (1) improve PT fluids to analytically behave more like fresh, human serum; (2) improve instrument design and reagent formulation; and (3) select methods and methodologic parameters that are more "robust" and less sensitive to the exact character of processed calibrators, quality control, and PT materials.

Bias↗

Microscope-assisted precision dentistry.

To enhance their vision for both clinical and laboratory procedures, an increasing number of dental practitioners are introducing magnification into their practices. Most are using either simple or compound loupes mounted on glasses frames. And although magnification is not new to dentistry, it is a trend that is gaining a broader acceptance among both seasoned practitioners and recent graduates. Many dental schools are allowing their students to use loupes on a discretionary basis, so the notion that magnification is reserved only to compensate for deteriorating vision is rapidly disappearing. Dental professionals have also begun to recognize that the quantity and quality of light in the working field is just as important as magnification. Headlamps with focused, color-correct light sources in combination with loupes are becoming popular. It is highly unlikely that a practitioner using loupes would relinquish them and return to practicing without magnification. The newest addition to the vision enhancement arena in dentistry is the operating microscope. In some medical subspecialties--such as otolaryngology, ophthalmology, plastic surgery, and neurosurgery--extensive microsurgical training is required to perform procedures at acceptable standards of precision. In 1998, the American Association of Endodontists (AAE) elected to mandate that all endodontic postgraduate students demonstrate proficiency using an operating microscope before they receive their certificates. Microscope use has also been reported in periodontics. For several decades, many dental laboratory technicians have used stereomicroscopes for trimming dies, refining castings, and performing other procedures that require a high degree of precision. However, according to microscope manufacturers, most current instrument sales are to general practitioners, who are not limiting the use of their microscopes to endodontic therapy--they are using them for a wide variety of procedures. Microscopes have the potential to enhance a dental practitioner's vision to unprecedented levels, but there are some practical questions that need to be addressed. What kind of visual acuity do dentists really need to perform high-quality dentistry? If a dentist wants to improve his or her vision, do loupes provide an adequate level of magnification? Is using a microscope too complicated for restorative and prosthodontic procedures, and how long does it take to become proficient with a microscope? These are some of the questions I posed to two outstanding dentists who have had extensive clinical experience using surgical microscopes. I also share my own experience with a microscope.

Dental Equipment↗

[In Process Citation]

A main basis of this habilitation thesis is the development of a portable, mains-free measurement device for determining breath ethanol concentrations (BrEC) both during spontaneous breathing and in mechanically ventilated patinets undergoing inhalation anaesthesia, for detecting and quantifying irrigation fluid absorbed during endourological surgical interventions. Here a respired gas has to be measured which compared to other usually measured gases 1) is present in substatially smaller concentrations, 2) is subject to significant influences by temperature and humidity in the expired air, and 3) can only be measured discontinuously in the alveolar air due to technical limitations of the sensor. The basis for investigating accuracy of measurement was not just evaluation of the device using different lung models, but also a comparison with the target parameter "absorbed irrigation fluid" using another further-developed reference procedure, i.e. direct measurement of sorbitol and mannitol concentrations in serum. This has the added advantage that even when ethanol monitoring is not available, another laboratory procedure is indeed available for directly evaluating the absorption of irrigation fluid. In the clinical aspects of this thesis, ethanol monitoring helped show that during transurethral resection of the prostate (TURP) in spontaneously breathing patients undergoing regional anaesthesia, irrigation fluid was intravascularly absorbed not more often, but more rapidly and in larger quantities than it was in mechanically ventilated patients undergoing inhalation anaesthesia. A possible reason for this was the significantly reduced central venous pressure observed in the group of patients undergoing regional anaesthesia. The diagnosis of a delayed extravascular absorption of irrigation fluid during percutaneous nephrolithotripsy (PNL), made with the assistance of the ethanol monitoring, was associated with a significantly prolonged period of hospitalization in the clinic and an increase in opioid requirements. This finding can be explained pathophysiologically by an increased trauma to the kidney with injury to bordering organ structures. As a result of close co-operation with several departments of the Medical University of Lubeck, we now have at our disposal an excellent BrEC-measuring device for detecting and quantifying absorbed irrigation fluid during urosurgical procedures. The results of the clinical studies presented here underscore the value of the newly-developed AlcoMed 3011.

Journal Article↗