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L’une des exigences de la norme se rapporte aux procedures analytiques dont le laboratoire doit disposer pour tous les examens pratiques. Le contenu de ces procedures n’est decrit qu’a titre d’indication. Lorsque les dispositifs utilises font l’objet d’un marquage CE, les fiches techniques produites par les differents fournisseurs peuvent repondre a cette exigence. Leur manque d’homogeneite d’un fournisseur a un autre peut leur faire preferer une redaction du type de celle proposee dans cet article. Des versions simplifiees peuvent etre egalement redigees pour faciliter le travail sur le terrain. L’ensemble de cette documentation peut etre presente sous forme electronique, ce qui en facilite la consultation au laboratoire. Un modele de procedure analytique applicable aux differents examens est presente en annexe de cet article.

The internal quality control is a key technical requirement through accreditation by the NF EN ISO 15189. This document presents recommendations to assist the medical laboratory to design, implement and operate daily and retrospectively an efficient system of internal control quality. It identifies the important issues attached to these different steps.

The results obtained using automatic analysers have to be reviewed before release to the laboratory information system (LIMS) for definitive validation by the authorised person. The objective of such a review is to ensure that quality indicators are in agreement with the defined requirements and that the procedures have been carefully fulfilled.

La norme NF EN ISO 15189 requiert l’evaluation de l’incertitude de mesure des resultats lorsque cela est possible et pertinent. Cet article propose des recommandations pour l’evaluer a partir de donnees disponibles au laboratoire de biologie medicale en illustrant egalement l’interet d’une telle determination.

A chronic microcytosis and hypochromia without any iron deficiency were observed in an 11-year-old boy of French Caucasian origin. The same hematological findings were also found for his mother. No abnormal hemoglobin (Hb) was detected using isoelectric focusing, cation exchange liquid chromatography and reversed phase liquid chromatography of the globin chains but DNA sequencing revealed a CTGCCG transition at codon 106 (Leu--Pro) of the alpha1-globin gene in both of them. As the alpha/beta mRNA ratios, determined by reverse-transcriptase real-time quantitative polymerase chain reaction (PCR), are not concordant with an alpha-thalassemia (alpha-thal) state, we hypothesize that the underlying physiopathologic mechanism is an assembling defect of the Hb Charlieu molecule, rather than an instability of the alpha(Charlieu) mRNA. Moreover, genetic counseling and patient information are required in this family to prevent potentially severe alpha-thalassemias in following generations.

Les tests dynamiques en endocrinologie ont connu leur apogee il y a maintenant plus d’une generation de praticiens. Ils sont aujourd’hui reserves aux diagnostics rares et difficiles, rencontres par les medecins specialistes Endocrinologues et, plus exceptionnellement, par les non specialistes.

External quality assessment is an important issue in the demonstration of the quality of analytical process. The aim of this document is to help the laboratory in the choice, implementation and interpretation of external quality assessment schemes.

Accuracy of results depends on the traceability of the standards values to a reference system. According to the ISO 15189 requirements, the laboratory has to document the traceability of the value of the standards used.

The maintenance of automatic analysers and associated documentation taking part in the requirements of the ISO 15189 Standard and the French regulation as well have to be defined in the laboratory policy. The management of the periodic maintenance and documentation shall be implemented and fulfilled. The organisation of corrective maintenance has to be managed to avoid interruption of the task of the laboratory. The different recommendations concern the identification of materials including automatic analysers, the environmental conditions to take into account, the documentation provided by the manufacturer and documents prepared by the laboratory including procedures for maintenance.

La determination des intervalles de reference repose sur des recommandations etablies par des experts de la federation internationale de chimie clinique et de medecine de laboratoire (IFCC-LM). Celles-ci sont difficilement applicables en l’etat dans les laboratoires de biologie medicale. Une recente revision des recommandations initiales apporte des solutions concretes en proposant un protocole simple de verification des intervalles de reference publies.

We have assessed turnaround time (TAT) for urgent laboratory analysis. Twelve hospital laboratories participated to this study. All laboratories have organized a classification of a management system of urgent analyses. The TAT reporting were relatively homogeneous for 12 laboratories. We have defined TAT as time of specimen receipt in the laboratory to time of results reporting. This TAT divides into 4 groups: close to 50 minutes for analyses as TP, D-dimeres, CRP (C Protein Reactive), HCG, troponin, alcoholhemia, K, lipase; 35 minutes for the cytology of cerebrospinal fluid; 25 minutes for complete blood cell count and 15 minutes for blood gases. All laboratories have accepted to TAT as a quality indicator. Quality indicator data should be collected in time to identify and correct problems to implemente effective interventions and to standardize processes among clinical laboratories.

We compared the results of two methods of measurement of HbA(1c) before replacing the current method on Integra 800 by the HPLC method on an apparatus recently put on the market, the G8. The comparative study of the results for 119 patients was carried out. The reproducibility obtained with the G8 method is good with CV = 0 for the control Level 1 at 5.6%, CV = 0.6% for Level 2 at 10.5% and CV = 0.73% for the Bio-Rad control at 5.7%. The comparison of the results of HbA(1c) gives the Passing - Bablock equation: Y (G8) = X (Integra) + 0.10 with r = 0,996. Systematic bias is of 0.092% and the ratio of the G8/Integra averages of 1.014 (7.43 %/7.34 %). Only 8 results out of the 119 are out of limits of more than 0.4% between the two methods. They are only 4 after bringing together the results by correlation. The two methods provide results with exactitude in conformity with the recommendations of the French governmental agency (Afssaps). The G8 method is slightly better regarding accuracy and precision.

Background Jaundice is frequent in neonates and can cause severe complications, especially in premature neonates, particularly the risk of developing acute bilirubin encephalopathy. Our purpose was to verify if determination of total bilirubin (TBIL) in whole blood on an ABL 735 blood gas analyzer with a spectrophotometer module could provide an analytical alternative to chemical methods of TBIL measurement. Methods Our multicenter comparative study involved four hospital laboratories. We studied the repeatability and reproducibility of ABL 735 TBIL measurements in two control sera of medium (N1, 58.1 micromol/L) and high (N2, 275.3 micromol/L) TBIL levels. The same study was simultaneously conducted on four chemistry instruments (two LX 20, one Integra 800 and one Hitachi 917) using four Jendrassik-Grof derived methods. At one site, repeatability was performed with two adult whole-blood samples containing low and high TBIL levels (55.1 and 312.6 micromol/L). Results Repeatability tests provided coefficients of variation (CVs) between 0.67% and 1.86% on the ABL 735 system, vs. 0.35% and 1.96% for the chemistry instruments. Reproducibility tests for the same control sera resulted in CVs between 1.01% and 3.55% for the ABL 735 and between 0.52% and 3.65% for the chemistry instruments. Recovery for the N1 and N2 control sera was 102-120%. A correlation study of TBIL determination in whole blood vs. plasma was conducted on 473 neonatal blood samples. Correlation coefficients between whole blood and plasma TBIL ranged from 0.969 to 0.994. Passing-Bablok equations were y=1.17x+9.7 [site 1 (IP)], y=1.01x+5.6 [site 2 (JPB, MR)], and y=1.00x-20 [site 3 (AS)]. Only 10% of the results fell outside the 10% range in the bias-corrected Bland-Altman difference plot for the ABL 735 method compared to traditional laboratory methods. Conclusions The ABL 735 instrument is reliable for measuring TBIL in 70-microL whole blood samples from neonates. Thus, this method might allow significant blood savings in preterm neonates. Correlation with the reference method for plasma or sera must be established to ensure good follow-up of patients.

The renal excretion of 3-hydroxyproline (3-HYP), an isomer of 4-hydroxyproline (4-HYP) found 6-10 times more in basement membrane collagen than in interstitial collagen, was investigated in control subjects and in 58 adult patients with various kidney diseases. With the exception of polykystic renal disease, all the nephropathies were investigated by renal biopsy. In normal adult subjects urinary 3-HYP was 12.5 +/- 3.5 (SD) mumol/24 h, 4-HYP 226 +/- 62 mumol/24 h and the percentage ratio 3-HYP/4-HYP 5.5 +/- 0.5. This ratio was twice as little during growth because of a relative excess of 4-HYP. In patients with acute glomerular disease (acute and subacute glomerulonephritis, lupus nephritis...) (n = 13) 3-HYP was 17.1 +/- 5.8 mumol/24 h (p less than 0.01 when compared with the normal) and 4-HYP 234 +/- 77 mumol/24 h. The ratio between the two values was 7.3 +/- 0.7 (p less than 0.001). Such an increase in 3-HYP was not observed in patients with chronic glomerulonephritis (n = 24) where 3-HYP was 9.6 +/- 5.7 mumol/24 h and 3-HYP/4-HYP 6.0 +/- 1.6, neither in patients with diabetic glomerulonephritis (n = 6). In chronic interstitial nephritis (n = 8) the 3-HYP/4-HYP ratio was decreased with the exception of polykystic renal diseases (PKD), where it was increased (p less than 0.001). The daily urinary contents of 3-HYP and 4-HYP were slightly altered by renal insufficiency. In glomerulonephritis with nephrotic syndrome whatever the histological lesions, urinary 3-HYP did not change significantly. These preliminary results indicate that urinary 3-HYP (1) is increased when glomerulonephritis is clinically acute or subacute; (2) is increased in PKD suggesting a possible inborn error of collagen metabolism.