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. 2024 Mar 9;17(1):68.
doi: 10.1186/s13104-023-06571-0.

Quality assessment of malaria microscopic diagnosis at the Aristide Le Dantec University Hospital of Dakar, Senegal, in 2020

Mamane N Garba  1   2 , Awa B Dème  3   4 , Khadim Diongue  3   4 , Younousse Diédhiou  3   4 , Amadou M Mbaye  4 , NDèye M Dia  4 , N'Dèye A Seck  4 , Daba Zoumarou  3   4 , Lamine Ndiaye  3   4 , Mamadou S Yade  3   4 , Baba Dièye  3   4 , Aita Sène  3   4 , Abdoulaye Tine  3   4 , Mariama Touré  3   4 , Nogaye Gadiaga  3   4 , Awa Fall  3   4 , Bassirou Ngom  3   4 , Djiby Sow  3   4 , Aliou Ndiaye  3   4 , Astou Keita  3   4 , Mame F Ndiaye  3   4 , Jules F Gomis  3   4 , Nana F Diop  3   4 , Guète Diallo  3   4 , Ibrahima M Ndiaye  3   4 , Elhadj M Ba  3   4 , Omar Bitèye  3   4 , Cheikh Ndiaye  3   4 , Fama S D Mbodji  3   4 , Pape O Ndiaye  3   4 , Tolla Ndiaye  3   4 , Amy Gaye  3   4 , Mouhamad Sy  3   4 , Yaye D Ndiaye  3   4 , Mame C Seck  3   4 , Mouhamadou Ndiaye  3   4 , Aida S Badiane  3   4 , Mamadou A Diallo  3   4 , Daouda Ndiaye  3   4
Affiliations

Quality assessment of malaria microscopic diagnosis at the Aristide Le Dantec University Hospital of Dakar, Senegal, in 2020

Mamane N Garba et al. BMC Res Notes. .

Abstract

Background: Following WHO guidelines, microscopy is the gold standard for malaria diagnosis in endemic countries. The Parasitology-Mycology laboratory (LPM) is the National Reference Laboratory and is currently undergoing ISO 15189 accreditation. In this context, we assessed the performance of the laboratory by confirming the reliability and the accuracy of results obtained in accordance with the requirements of the ISO 15189 standards. This study aimed to verify the method of microscopic diagnosis of malaria at the LPM, in the Aristide Le Dantec hospital (HALD) in Dakar, Senegal.

Methods: This is a validation/verification study conducted from June to August 2020. Twenty (20) microscopic slides of thick/thin blood smear with known parasite densities (PD) selected from the Cheick Anta Diop University malaria slide bank in Dakar were used for this assessment. Six (6) were used to assess microscopists' ability to determine PD and fourteen (14) slides were used for detection (positive vs negative) and identification of parasites. Four (4) LPM-HALD microscopists read and recorded their results on prepared sheets. Data analysis was done with Microsoft Excel 2010 software.

Results: A minimum threshold of 50% concordance was used for comparison. Of the twenty (20) slides read, 100% concordance was obtained on eight (8) detection (positive vs negative) slides. Four (4) out of the six (6) parasite density evaluation slides obtained a concordance of less than 50%. Thirteen (13) out of the fourteen (14) identification slides obtained a concordance greater than 50%. Only one (1) identification slide obtained zero agreement from the microscopists. For species identification a concordance greater than 80% was noted and the microscopists obtained scores between 0.20 and 0.4 on a scale of 0 to 1 for parasite density reading. The microscopists obtained 100% precision, sensitivity, specificity and both negative and positive predictive values.

Conclusion: This work demonstrated that the microscopic method of malaria diagnosis used in the LPM/HALD is in accordance with the requirements of WHO and ISO 15189. Further training of microscopists may be needed to maintain competency.

Keywords: Plasmodium; Diagnosis; Senegal; Sensitivity; Specificity.

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Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Fig. 1
Fig. 1
Concordance of results obtained between microscopists on the recognition of positive vs negative slides. formula image 100% concordance of microscopists on the recognition of positive vs negative slides
Fig. 2
Fig. 2
Concordance of results obtained between microscopists on parasite density. formula image Positive slide for parasite density (PD). formula imageConcordance of results obtained (4/6)
Fig. 3
Fig. 3
Concordance of results obtained between microscopists on control slide identification. formula image Concordance of control slide identification
Fig. 4
Fig. 4
Concordance of results obtained between microscopists on the identification of non-falciparum species. formula image Null concordance on Plasmodium ovale (Po) positive slide
Fig. 5
Fig. 5
WHO scoring of microscopists [between 0 (lowest) and 1 (highest)]
See this image and copyright information in PMC

References

    1. PNLP-Sn PNDLCLP. Bulletin de surveillance sentinelle du Paludisme 2018. 2018.
    1. PNLP-Sn PNDLCLP. Plan strategique national de lutte contre le paludisme au Senegal 2016–2020. 2016. p. 116.
    1. PNLP. Bulletin epidemiologique du paludisme au Senegal. 2019.pp.1–54.
    1. WHO. World malaria report 2019. 2019.
    1. OMS. Diagnostic microscopique du paludisme manuel d’assurance qualité. 2016.