Establishing an External Quality Assessment (EQA) Program for Urinalysis in Medical Laboratories of Thailand.

Thailand Association of Clinical Biochemists (TACB) introduced External Quality Assurance schemes (EQAs) for urinalysis (UA) using urine strips in medical laboratories of Thailand. The few available External Quality Assessment (EQA) programs on urinary microalbumin rarely include an evaluation of clinical cases. The aim of the present study was to assess a descriptive analysis of biochemical urinalysis including urine microalbumin in the Thailand laboratory practice. From January 2021 to December 2021, four surveys were organized. EQA urine samples were distributed to the participants by mail. The participants measured the UA of 2 samples quarterly and returned the results together with the information about their instruments and suggestion for the performance of the laboratory report quarterly. Moreover, summary of the situation of each laboratory performance was feedbacked by online system. Fifty-eight laboratories participated in the survey. The EQA panels included positive and negative samples. The analytical results for passed parameters of urine chemical test range from 79.3-100%. All special tests; microalbumin, creatinine, and beta-HCG showed correct result from 85.1-96.1%. The overall accuracy, specificity, and sensitivity were 92.6, 85.7, and 75,4%, respectively. The major issues were observed: the low sensitivity for the detection of low-concentration samples and the incapacity of several methods to detect the positive sample. The assessment is needed to continuously evaluate the improvement proficiency of laboratories in Thailand.

Abnormal kinetics of erythrocyte sodium lithium countertransport in renal transplant recipients.

Cardiovascular disease is now the most common cause of death in renal transplantation. Cyclosporine (CsA)-associated hypertension might be a major cause of cardiovascular risk factors. There is evidence suggesting that one mechanism of CsA toxicity might be mediated through alteration of membrane lipid peroxidation, which can activate cellular pathways. Erythrocyte sodium lithium countertransport (Na/Li CT) is a sensitive membrane protein that is abnormal in several hypertensive-related diseases. We have studied the kinetics of erythrocyte Na/Li CT in 38 renal transplant recipients. Group 1 (15 patients) received CsA, azathioprine, and prednisolone (C+A+P), Group 2 (15 patients) CsA and prednisolone (C+P), and Group 3 (8 patients) azathioprine and prednisolone (A+P). Compared with the normal subjects, the Michaelis constant for extracellular sodium (Km) of erythrocyte Na/Li CT was lower among the CsA-based regimen groups (C+A+P and C+P), but not the A+P group. The maximum velocity (Vmax)/Km ratio was also higher among the C+A+P and C+P groups than the A+P group. These abnormalities of Na/Li CT kinetics might be due to abnormalities of cell membrane functions, caused by immunosuppressive drugs, particularly CsA. Further studies involving the effect of CsA on the physiological function of membrane thiol proteins are required.

Erythrocyte sodium lithium countertransport in renal transplant recipients with mycophenolate mofetil and low-dose cyclosporine.

Hypertension, a common complication after renal transplantation, has many potential etiologies. Erythrocyte sodium lithium countertransport (Na/LiCT) is a sensitive membrane protein that has been observed to be abnormal in several hypertension-related diseases. We have shown that the kinetics of Na/LiCT were abnormal in renal transplant recipients treated with usual dose of cyclosporine (CsA). We postulated that CsA might be a cause of post-renal transplantation hypertension. There is evidence showing that the severity of CsA nephrotoxicity is dependent on the dose. Mycophenolate mofetil (MMF) may allow CsA dose reduction without increasing the risk of rejection. We studied the impact of CsA dose reduction in association with MMF on the kinetics of erythrocyte Na/LiCT in renal transplants. In 15 renal allograft recipients, 2 g/d MMF were introduced and the CsA dose reduced to reach whole-blood levels between 70 and 100 ng/mL within 1 month. CsA doses and levels, renal function parameters, blood pressure, and the kinetics of Na/LiCT were evaluated before and 6 months after CsA dose reduction. Overall, renal transplant recipients with usual doses of CsA showed a lower Km with a higher Vmax/Km ratio for erythrocyte Na/LiCT than normal controls (Km, 40 +/- 4 vs 74 +/- 11; P <.05; Vmax/Km, 10.2 +/- 1.7 vs 6.1 +/- 0.9; P <.05). After 6 months of CsA dose reduction, the Km and Vmax/Km of Na/LiCT were similar to those of normal controls (Km, 66 +/- 8 vs 74 +/- 11; P >.05; Vmax/Km, 5.7 +/- 1.2 vs 6.1 +/- 0.9; P >.05). These results demonstrate that reduction of CsA dose in combination with MMF may improve the kinetics of Na/LiCT and lessen the long-term side effects of CsA without increasing the risk of rejection.

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.

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.

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.

Prevalence of endemic distal renal tubular acidosis and renal stone in the northeast of Thailand.

We have previously reported a large group of patients with endemic distal renal tubular acidosis (EdRTA) admitted to the hospitals in the northeast of Thailand. Since large number of patients were identified in a relatively short period of time, and in an area whose population is homogeneous, we were led to investigate the prevalence of the condition in the area. A survey was conducted in five villages (total population of 3,606) within the northeast of Thailand. 3,013 villagers were examined for urinary citrate concentration and short acid loading test was performed in those with low urinary citrate. 2.8% of the population (2.2-3.4%, 95% confidence interval) failed to lower their urine pH after acid loading; within this group, 0.8% of the population had serum potassium less than or equal to 3.5 mEq/l. In addition a large number of villagers were found to have low urinary citrate concentration and there was concurrent high prevalence of renal stone. The prevalence of EdRTA and renal stone was higher in villagers with poorer socioeconomic status, suggesting that environmental factors play a major role in their pathogenesis. Villagers with acidification defect have 2.4 times the chance of having renal stone and/or nephrocalcinosis. EdRTA is therefore one of the important factors responsible for the high prevalence of renal stone in the area. In conclusion we have confirmed the high prevalence of EdRTA in the northeast of Thailand and provided data showing high prevalence of renal stone and hypocitraturia in the same population.

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.

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)

Endemic primary distal renal tubular acidosis in Thailand.

Within a period of 3 years, 103 patients with primary type I distal renal tubular acidosis were reported from two hospitals in the northeast of Thailand, with cases peaking in the summer. The patients' age ranged from 18 to 76 with a mean and mode of 39 and 47 years, respectively. The female to male ratio was 3.3:1. All patients presented with generalized muscle weakness and bone pain and nocturia were frequent manifestations. Hypokalaemia and hyperchloraemic metabolic acidosis were constant findings and were more pronounced in patients with roentgenographic evidence of nephrocalcinosis and osteomalacia. Urinary citrate was extremely low in most of the patients. Nephrocalcinosis and/or renal stones were present in 27.2% of the patients and osteomalacia was found in 23.3%. All patients were Lao-Thai. This is the first report of a large group of patients with distal renal tubular acidosis, endemic within a particular geographical region.

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.