The External Quality Assessment [EQA] analysis achievement for excellent performance results in Clinical Microscopy

Kridsada Sirisabhabhorn and Supaporn PumpaClinical Microscopy & Parasitology Division, Medical Technology Laboratory, Thammasat Charlermprakiet Hospital,

Pathumthani, Thailand 12120

Nowadays, the external quality assessment [EQA] is necessary for qualification control of lab results and also reduces bias of testing. EQA analysis materials for

microscopy are including urinary elements, stool sediment and parasitic blood film which are provided from external examiners for clinical laboratory performance surveillance. This study we analyze the previous EQA results of microscopy from Ministry of Public Health and Faculty of Medical Technology, Mahidol University since 2006-2013 for the improvement of diagnosis performance. The data were obtained from the EQA results of 2 stool sediments, 2 urinary elements and peripheral blood parasitemiasmears during 2006 to 2013. The descriptive analysis of EQA results demonstrated that parasites using as target were Blastocystis hominis 12.07%[7], Entamoeba coli12.07%[7], Trichuris trichiura 10.34%[6], Ascaris lumbricoides 8.62%[5] and Giardia lamblia 8.62%[5]. However, for the Blastocystis hominis investigation showed misdiagnostic value. For urinary elements results demonstrated the target volume of erythrocyte, leukocyte, bacteria and simple squamous cell were 16.67%[7], 16.67%[7], 14.29%[6] and 11.90 %[5] respectively. However leukocyte grading value was misdiagnosis, which higher than target value for 2 levels. The microscopic illustrates surveillance was created the diversity of 14 urinary elements both of EQA sources. Finally, peripheral blood parasitemia smears shown the percentages of Plasmodiumfalciparum, P. vivax and Wuchereria bancrofti at 45.45%[5], 45.45%[5]and 9.09%[1] respectively. The performance value of parasitic samples, urinary elements and peripheral blood parasitemia smears testing from EQA of Ministry of Public Health were 3.62±0.63, 3.61±0.47 and 3.53±1.16 respectively. Moreover, the performance value of EQA from Mahidol University illustrated the median score at 3.8 [grade A]. In conclusion, our clinical microscopy lab shows excellent performance. The benefit of these results can advise our lab in focusing and reducing the misdiagnosis report and maintaining the excellent qualitative performance.

Abstract

Introduction

Key words : external quality assessment, urinary elements, parasite, performance

The EQA [external quality assessment] is the material specimens which external

authority examiners assigned for checking accuracy of our results. In Microscopy & Parasitology job has provided 2 sources of EQA examiners, Ministry of Public Health & Department of Clinical Microscopy the Faculty of Medical Technology MahidolUniversity Thailand, materials composed 3 kinds of specimens as stool sediment, urinary sediment and peripheral blood film for investigated accuracy of results. Before 2006, all previous results of EQA results in parts of Microscopy & Parasitology has not non-validated and undefined levels of laboratory performance – bad, fair, good and excellent – reasonable for observe our correctly report. This objective study to evaluated technician performance and integrated previously results for enhance quality report improvement. The expectation from study can be apply in routine and next EQA trial in our laboratory.

1. Data collection : All data were obtained with 2 sources of EQA above

mention which composed 14 trials of both of Ministry of Public Health and Department of Clinical Microscopy the Faculty of Medical Technology, MahidolUniversity Thailand.

2. All 14 trials of Ministry of Public Health’s EQA were content that trials/years; 1-3/2006, 1-3/2008, 3/2010, 1-3/2011, 1-3/2012 and 1/2013. Another, Mahidol’s EQA were 1-3/2007, 1-4/2008, 1-4/2011 and 1-4/2012 respectively.

3. Each trial was compared our results with EQA target results and then analyzed data to reveal performance by descriptive statistic.

Material & Method

Results

Conclusion & Discussion

The previously of EQA results accumulated for 5 yrs were complained that the most of parasite material in stool sediment which are using as target from Ministry of

Public Health EQA were Blastocystis hominis stage of vacuolated value as 12.07% and often misdiagnosis in our EQA. Following as parasite target using were commonly intestinal parasite such Entamoeba coli, Trichuris trichiura, Ascaris lumbricoides and Giardia lamblia values as 12.07%[7], 10.34%[6], 8.62%[5] and 8.62%[5] respectively. The corner of urinary element assessment found that erythrocyte, leukocyte, bacteria and simple squamous cell were using as target. Moreover, leukocyte grading was classified grade over target value of EQA. Notification error of 2 points mention we should be respond activity for improve to correctly report further. The photo survey test of urinary elements were diversity as 14 kinds of elements in both of EQA form Ministry Public Health and Mahidol University. Lastly, the peripheral blood smear for investigated blood stream parasite were illustrated Plasmodium falciparum and P. vivax same value as 45.45%[5].

Conclusion, The our EQAs achievement which compose both of 2 EQAs source were performed over average 3.50 scores and median scores 3.80 scores in Ministry of Public Health’s EQA and Mahidol’s EQA respectively those illustrated in the excellent grade. The interest of study should be guide line for focusing on commonly error parasite identification and urine elements grading. From this study we have attempt to remain satisfy results of EQA and apply to using for routine quality report improvement .

Trials

ST1A [stool sediment 1] ST1B [Stool sediment 2] UA2A [urine ] UA2B [urine] Blood film

EQA Target Missing value EQA Target Missing value Score EQA Target Missing value EQA TargetMissing

value Score EQA Target score1/2006 Blastocystis hominis Hook worm egg. None Ascaris lumbricoides 3.20 RBC Bacteria Mucous thread 3.60 P.f. 4.00

Echinostoma spp. Trichostrongylus orientalis WBCTaenia spp. Sq.

Bact.2/2006 Teania spp. Hook worm egg. Entamoeba coli Hook worm egg. 4.00 RBC 3.50 N/A N/A

Opisthorchis spp. Endolimax nana WBCTrichuris trichiura Bact.

Mucous3/2006 Giardia lamblia Ascaris lumbricoides 4.00 RBC RBC Broad rbc cast 3.00 P.V. 4.00

Hookworm Hymenolepsis nana WBC WBC Triple phosphateSq.

Bact.1/2008 Entamoeba coli Giardia lamblia Teania spp. Blastocystis hominis 3.33 RBC RBC Bladder epithelial 2.40 W. b. 0.00

Opisthorchis spp. Hook worm egg. Giardia lamblia WBC WBC Hyaline castBlastocystis hominis Trichuris trichiura Ascaris lumbricoides Sq.

yeast2/2008 Giardia lamblia Endolimax nana Capillaria philippinensis 4.00 RBC Mucous oval fat body 3.17 P.v. 4.00

Hymenolepsis diminuta WBC cast Hb. CastParagonimus spp. Sq.

Bact.cast

3/2008 Entamoeba coli Trichuris trichiura 4.00 RBC sulfa crystalepithelial

cast 3.80 P.f. 4.00Blastocystis hominis Ascaris lumbricoides WBC wbc cast

Entamoeba coli Sq.Hymenolepsis nana Bact.

3/2010 Entamoeba coli Hymenolepsis diminuta 4.00 RBC Hyaline cast Oval fat 3.86 P.v. 4.00Lung fluke WBC Waxy cast starch

Sq. Mucousgr.cast Budding yeast

amorphous Pseudo hyphaeBact. Amorphous

1/2011 Enterobius vermicularis Ascaris lumbricoides Trichuris trichiura 4.00 RBC wbc cast 4.00 N/A N/AOpisthorchis viverrini Hookworm WBC uric crystal

wbc cast2/2011 Trichuris trichiura Giardia lamblia Hookworm 4.00 RBC Fatty cast Bladder cell 3.50 P.f. 4.00

Hookworm Teania spp. WBC Mixed cast Calcium oxalatewbc cast

3/2011 Hymenolepsis diminuta Trichuris trichiura Entamoeba histolyticaBlastocystis hominis Blastocystis hominis 2.67 RBC sq.epi. fatty cast 3.75 NF. 4.00

WBC White blood cell castcalcium oxalate

1/2012 Giardia lamblia Giardia lamblia 3.50 Hb cast 4.00 P.f. 4.00Enterobius vermicularis Trichuris trichiura Fasiola spp. Clue cell

Tyrosine2/2012 Entamoeba coli Blastocystis hominis Entamoeba coli Blastocystis hominis 2.00 caudate cell bladder cell 4.00 P.f. 3.00

Blastocystis hominis Opisthorchis viverrini Blastocystis hominisOpisthorchis viverrini Teania spp.

3/2012 Ascaris lumbricoides Ascaris lumbricoides 4.00 strarch 4.00 P.v. 3.33Trichuris trichiura Trichuris trichiura waxy

Paragonimus sp. Paragonimus spp.wbc

clumpingrbc

1/2013 Iodamoeba butschlii Blastocystis hominis Entamoeba coli 4.00 Fatty cast 4.00 P.v. 4.00

Lung fluke Endolimax nanaTriple

phosphateAverage 3.62 Bacteria Average 3.61 Average 3.53

S.D. 0.63 Mucous S.D. 0.47 S.D. 1.16

Trials MIS score median score Grade Microscopic illustrated

1/2007 3.80 3.80 A Budding yeast

2/2007 3.00 3.80 B Calcium oxalate

3/2007 3.80 3.80 A Macrophage/histocyte

1/2008 3.10 2.30 A Uric crystal

2/2008 4.00 3.80 A Bilirubin crystal

3/2008 2.80 3.00 B Bilirubin cast/Granular cast/Bile cast

4/2008 3.90 3.90 A Dysmorphoc rbc/Acanthocyte/G1 cell

1/2011 3.80 3.50 A Cystine crystal

2/2011 3.40 3.10 A Macrophage

3/2011 2.90 1.90 B Granular cast

4/2011 3.90 3.80 A Cholesterol crystal

1/2012 3.40 3.80 A Starch

3/2012 3.80 3.80 A Renal epithelial cast

4/2012 3.80 3.80 A Calcium oxalate

Summary 3.80 3.80 A Excellent qualification grade

Blastocystis hominis12%

Entamoeba coli12%

Trichuris trichiura10%

Ascaris lumbricoides9%

Giardia lamblia9%

Teania spp.7%

Hookworm5%

Hymenolepsis diminuta5%

Paragonimus spp.5%

Opisthorchis spp.3%

Opisthorchis viverrini3%

Enterobius vermicularis3%

Hymenolepsis nana3%

Iodamoeba butschlii2%

Endolimax nana2%

Echinostoma spp. 2%

Capillariaphilippinensis

2%

Lung fluke2%

Entamoeba histolytica2%

Fasiola spp.2%

% of parasite target values in Ministry of Public Health's EQA

Acknowledgements : We would like thank for his kindness to A.j. Jirayut jaipaew for advice and recommendation in this study and Mr. Palakorn Puttarak, Lab director of Medical Technology Laboratory of Thammasat Charlermprakiet Hospital for support poster presentation.

Table 2. Illustrated the EQA scores of urinary element grading and diversity in microscopic photo illustrations of Mahidol University’s EQA.

Chart 1. Illustrated the percent of parasite target were using in Ministry of Public Health’s EQA which have been accumulating since 2006 to 2013.

Table 1. Illustrated the detail data of the Ministry of Public Health’s EQA since 2006 to 2013.

Abbreviations : P.f.[Plasmodium falciparum], P.v.[Plasmodium vivax], W.b.[Wuchereria bancrofti], NF.[Not found], N/A[Non avaliable]