Accuracy and precision of the i-STAT portable clinical analyzer: an analytical point of view.

The introduction of a new point-of-care testing (POCT) instrument into the market affects medical practice and laboratory services. The i-STAT is designed to improve the speed in the decision making of the medical profession. However, reliability of results would ensure the quality of laboratory data. We, therefore, made an evaluation of the performance of i-STAT using a disposable cartridge EG7 + which is capable of measuring pH, pO2, pCO2 (blood gas), Sodium, Potassium (Electrolytes), Ionized calcium and Hematocrit with only 10 microliters of lithium heparinized blood in 2 minutes. The results were compared with those obtained from routine methods. The results were found to be accurate, precise and correlated with acceptable methods used routinely in the laboratory.

Interlaboratory results for blood lead proficiency testing program in Thailand.

Between December 1994 to 1995, Faculty of Medical Technology, Mahidol University have a thirteen laboratory to participate in Blood Lead Proficiency Testing Program (BLPT). Every-month the Toxicology Unit in Faculty of Medical Technology Mahidol University which served for Reference Laboratory Center for BLPT send the three lots of whole blood sample which made from bovine blood to the participants by EMS. After evaluation in term of accuracy: using 75 per cent correctly when compared with the target value. There are nine laboratory which have successful in blood lead below 20 micrograms/dL and three laboratory which passing the analysed when the concentration of blood lead at 21-50 micrograms/dL and 51-80 micrograms/dL. In term of precision evaluation the planning process will show that laboratory using Graphite Furnace Atomic Absorption Spectrophotometer (GFAAS) reported reliability than using Flame Atomic Absorption Spectrophotometer (FAAS). From joining with this program the participants will get three advantages, First the target value from the reference laboratory in Thailand and Singapore are similar with the Center for Disease Control (CDC) from the United State of America which known world wide for Reference Laboratory. In the second participants will develop the analysis and solve the problem by himself, The third advantage: will showing the superior, methodology and instruments which guarantee for quality assurance and guideline to standardized blood lead analysis in the International level.

Reference value for urinary deoxypyridinoline as a specific marker for measuring bone resorption in Thais.

In the next century, the increasing number of elderly and rising healthcare costs will bring with it metabolic bone problems, particularly osteoporosis. Deoxypyridinoline: Dpd in urine is a sensitive and specific marker for screening and monitoring of bone resorption in a variety of diseases affecting bone turnover and in risk groups especially in the postmenopause. The reference value among aging (21-60 years) of a healthy well defined group was studied by collecting the urine between 700-1000 hours and using the ELISA technique to determine the level of Dpd. The reference value of Dpd in 113 males and 298 females 1.3-6.5 and 1.5-6.9 nm Dpd/nm Creatinine respectively. The level of Dpd in females was significantly higher than in males at p < 0.028. However, the average value of deoxypyridinoline in postmenopause was higher than premenopause but not different at p = 0.05. There are many factors which influence the results so the overall reference value is only a guideline for screening in bone resorption.

Screening for urinary amphetamine in truck drivers and drug addicts.

Sixty-two urine samples from truck drivers and drug addicts were analysed by TDx (Abbott Laboratories) for amphetamines. Eighteen samples were found to be positive while the rest were negative. The eighteen samples were simultaneously determined for amphetamines by EMIT (Syva Company). Sixteen samples were found to be positive and 2 of negative samples had amphetamines levels of 0.48-0.85 micrograms/mL. When the same samples were subjected to qualitative screening and some were found false negative as follows: 7 cases in Color Test by using test solution kits amphetamine in urine (the Department of Medical Science, Ministry of Public Health), 8 cases by Albuscreen Ontrax for amphetamine (Roche Diagnostic System), 5 cases by amphetamine Double Antibody 125I-RIA (Diagnostic Products Corporation-DPC) and 3 cases by the method of Ten-One (DPC) respectively. But when forty four samples which gave negative results by TDx were subjected to Testing by EMIT and Ontrax. The results of both EMIT and Ontrax were negative. Some of forty four samples were false positive by the Color Test solution kit amphetamines in urine and amphetamine Double Antibody 125I-RIA. Reliability of results reported not only depends on the methodology or principle but also the sensitivity of the method.

Altered biochemistry substances, hematocrit and white blood cell count in cigarette smokers and alcohol drinkers.

The level of glucose, uric acid, cholesterol triglycerides and transminase (SGOT and SGPT) and also hematological data of hematocrit and white cell count of 1,542 workers age ranging from 35-53 years who came for physical check up during B.E. 2532 – 2534 were analysed for the groups of smokers, drinkers and smokers together with drinkers. All the three groups have significantly high level of biochemistry substances, hematocrit and white cell count than normal group (p < 0.005) except HDL-Cholesterol which is significantly lower than the normal group (p < 0.005). However, the white cell count of habitual drinkers and cholesterol level in smokers together with drinkers have no significantly different from the normal. We categorie the number of cigarette smoked by both questionnaires and the thiocyanate levels, and found the serum thiocyanate levels correlates with the number of cigarette smoked (p < 0.001).

Factors influencing the management of test turnaround time in emergency service.

By studying the turnaround time (TAT) of two emergency service laboratories for a period of five years, it was found that decentralized management is preferable since it enables more rapid solution of problem and speed which meets the purpose of each service. Factors involved in stat services are the selection of methodology, pre analytical, analytical and post analytical processes related to the utility of the work area, laboratory layout design, and the training of personal having a good attitude forwards service. Other factors are communication and relationship between teams in the laboratory and outside the laboratory or those related to planning for preventive and retrospective quality monitoring in laboratory service.

Acute toxicity of murdannia ioriformis.

Murdannia loriformis “Yaa Bei-jing” is widely used as remedy treatment in many kinds of cancers especially in breast cancer and carcinoma of bladder. According to WHO recommendation, four concentrations of fresh juice from “Yaa Bei-jing” (50, 100, 200, 300 times of therapeutic dose used in man) were given orally once to 4 groups of fasted rats aged 2-3 months. No abnormal symptoms were observed during 24 hours after feeding and through 14 days. Blood chemistry, CBC and histopathological findings of lungs, kidneys, spleens, livers and testis/ovaries were also within normal limits.

Urinary constituents in an endemic area of stones and renal tubular acidosis in northeastern Thailand.

Nephrolithiasis and endemic renal distal tubular acidosis are common in northeastern Thailand. The etiology is still unknown. It is generally accepted that urine electrolytes influence the capacity of urine to inhibit or promote renal and also bladder stones. The purpose of this study was to analyse the composition of the urine in the indigenous population in the northeast area and compare their values with data obtained from a group of age matched adults, living in Bangkok. Twenty-four hour urine samples from 23 normal adult villagers from six villages within the province of Khon Kaen and 34 normal adults living in Bangkok were collected, and the daily excretion of creatinine, uric acid, calcium and inorganic phosphate, sodium, potassium, chloride, magnesium and oxalate were assayed. Daily urinary sodium, potassium, chloride and phosphate of the villagers were significantly lower than those of Bangkokians. No difference in the urinary excretion of calcium, magnesium, uric acid, oxalate and creatinine was found. The Na/Ca, and Ca/PO4 ratios of villagers were significantly lower than those of the Bangkok subjects. The villagers excreted significantly lower amounts of Na in the face of relatively higher urinary Ca. The above data, combined with our previous study showing the low values of urinary citrate in the villagers in the same areas, strongly indicate that the indigeneous population is at high risk in developing urolithiasis. The causes for these electrolyte abnormalities are still unknown. Low contents of the major electrolytes in their diets might play an important role. Low phosphate output indicates low protein diets.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of hepatitis B surface antigen in Wat Srakaew school children.

Prevalence of Hepatitis B Virus carrier in adopted school age children is 12.5 per cent. When it is compared to Bangkok and Ayutthaya children, its prevalence is higher than children in Bangkok, but it is lower than children in Ayutthaya.

Urinary D-aminolevulinic acid in workers exposed to lead.

One hundred and fifty-five urine samples from workers in car painting, motor-bicycle or tricycle drivers, and printers were quantitatively analysed for delta-aminolevulinic acid. The levels were 0.86 + 0.32, 0.8 + 0.23 and 0.76 + 0.24 mg/dl, which were increased beyond normal levels by 63, 90 and 84 percent of the three respective worker groups.

Evaluation of the causes of error in analysis of routine tests.

The retrospective study is one of the part of quality control circle which will be improve the reliability and efficiency of laboratory service. We evaluated the result from the Department of Clinical Chemistry, Faculty of Medical Technology, Mahidol University which served routine analysis for out-patients and in-patients from Siriraj Hospital. After careful screening the random and systematic error we followed the design in planning of laboratory management between June to December 1987, there are 72 cases which had a definitive problem and error which was clarified in three categories:- preanalytical process 15.3%, analytical process 65.3%, and post analytical process 19.5%.

Laboratory screening programme for Thailand tobacco monopoly population.

One thousand and eight workers of Thailand Tobacco Monopoly, aged between 25-65 years were subjects to a check up by clinical chemistry laboratory examinations. It was found that workers aged between 41-50 years and 51-60 years made 26.8% and 41.1% respectively, and 38.9% had regular laboratory examination. Of those who had regular physical check up, 16% were for high blood pressure and 11.9% were for diabetes mellitus. Laboratory examinations of blood samples gave 2% positive HAA and abnormal levels of 4.6% for blood glucose, 3.7% for cholesterol, 2.8% for alkaline phosphatase, 2.3% for uric acid. 1.3% for transaminase (SGOT 2.1% and SGPT 1.3%), 0.2% for total protein and 0.1% for creatinine. Normal levels of blood constituents relating to liver and cardiac function for Thailand Tobacco Monopoly population by statistical calculation are consistently higher than those for the general population. Special attention should be given in regards to re-examintion of the workers 6-12 months after the first examination.