Today I used the BCSH audit template to perform a gap analysis on our procedures for the diagnosis of malaria, in comparison to the BCSH 2022 guidelines. British Society for Haematology guidelines for the laboratory diagnosis of malaria - Rogers - 2022 - British Journal of Haematology - Wiley Online Library.
I would recommend that all staff involved in laboratory malaria diagnosis, read the 2022 guidelines and also the following:
WHO information on ‘False Negative RDT results
and p.falciparum histidine-rich protein 2/3 gene deletions MAY 2016 (REV.
SEPTEMBER 2017 AND JULY 2019) https://apps.who.int/iris/bitstream/handle/10665/258972/WHO-HTM-GMP-2017.18-eng.pdf?sequence=1
Learning points- HPR2 deletions in P.Falciparum and how this may lead to a
negative RDT, prozone effect, frequent
negative RDT test for P.Ovale, inclusion of Babesia in the differential
diagnosis when the RDT is negative.
Date of completion |
10/10/22 |
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Name of lead author/ |
Clare Saddington |
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Specialty |
Haematology |
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Title |
An audit of
compliance with the British Society for Haematology guideline on laboratory
diagnosis of malaria |
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Background |
The British
Society for Haematology (BSH) has published guidance on the laboratory
diagnosis of malaria. This audit will review
compliance with some of the recommendations made. |
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Aim & objectives |
To review
whether: 1.
suspected malaria cases
are being appropriately tested 2.
cases of malaria are
being accurately diagnosed and appropriately assessed. |
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Standards & criteria |
If the target (specified as 100% or 0% for each criterion)
is not achieved, there should be documentation in the case notes that
explains the variance. 1.
Both thick and thin films should be routinely
prepared for malaria diagnosis; target 100%. 2.
Thin films should be stained with a Giemsa
stain and thick films with either a Giemsa or Field stain. Giemsa should be
used at pH 7.2; target 100%. 3.
Thick films should be examined by two trained
observers, each viewing a minimum of 200 high power fields; target 100%. 4.
If thick films are positive, the species
should be determined by examination of a thin film, again by two trained observers;
target 100%. 5.
In the case of Plasmodium falciparum or
Plasmodium knowlesi infection, the percentage of parasitised
cells or the number of parasites per microlitre should be estimated and
reported; target 100%. 6.
Rapid diagnostic tests (RDTs) for malarial
antigen should not be used instead of a film at any time including out of
hours; target 0%. 7.
All positive specimens or discrepant results
between RDT and films should be referred to a reference laboratory; target
100%. |
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Method
|
1. Sample
selection ·
All
requests for investigation of possible malaria parasites, either in a period
of one month or to give a total of 30 requests (whichever is more
appropriate).
2. Data to be
collected on proforma (see below). |
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Results
|
The results of this audit show the following compliance
with the standards.
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Conclusion |
Laboratory
procedure is compliant with the above standards in BCSH 2022 guidelines on
the laboratory diagnosis of Malaria.
I
would recommend however that all staff involved in Malaria diagnosis read the
following: ·
WHO information on ‘False Negative RDT results
and p.falciparum histidine-rich protein 2/3 gene deletions MAY 2016 (REV.
SEPTEMBER 2017 AND JULY 2019) https://apps.who.int/iris/bitstream/handle/10665/258972/WHO-HTM-GMP-2017.18-eng.pdf?sequence=1
Learning points- HPR2 deletions in P.Falciparum and how this may lead to a
negative RDT, prozone effect, frequent
negative RDT test for P.Ovale, inclusion of Babesia in the differential
diagnosis when the RDT is negative.
·
Also an awareness of guidance from Advisory
Committee for dangerous Pathogens (2015) Management
of Hazard Group 4 viral haemorrhagic fevers and similar human infectious
diseases of high consequence (publishing.service.gov.uk)
These
documents should be read as part of the Parasitology competency reassessment.
Staff where appropriate should
participate in NEQAS Blood Films for Parasites on a regular basis.
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Recommendations
for improvement
|
Present the result
with recommendations, actions, and responsibilities for action and a
timescale for implementation. Assign a person(s) responsible to do the work
within a time frame.
Some suggestions: ·
highlight areas of practice that are different ·
present findings. |
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Action plan |
Incorporate
recommendations of BCSH guidelines 2022 guidelines into new draft of
parasitology SOP RWF-BS-HAEM-SOP50 version 1.5. Include section on False
negative RDTs. Target date : October 2022 Responsibility : Clare Saddington
Distribute
link (or a hardcopy) of BCSH guidelines 2022 for the laboratory diagnosis of
Malaria British Society for Haematology
guidelines for the laboratory diagnosis of malaria - Rogers - 2022 - British
Journal of Haematology - Wiley Online Library WHO document on ‘False Negative RDT results
and p.falciparum histidine-rich
protein 2/3 gene deletions MAY 2016 (REV. SEPTEMBER 2017 AND JULY
2019) https://apps.who.int/iris/bitstream/handle/10665/258972/WHO-HTM-GMP-2017.18-eng.pdf?sequence=1 and Advisory Committee for dangerous
Pathogens (2015) Management of Hazard Group 4 viral
haemorrhagic fevers and similar human infectious diseases of high consequence
(publishing.service.gov.uk) Target date November 2022 Responsibility : Clare Saddington
Senior
BMS to provide a training/ review session of the above guidelines. Target date: January 2023 Responsibility : Clare Saddington
BMS
to participate in NEQAS blood films for parasites on a regular basis. Senior
BMS to coordinate this.
Target date: May 2023 Responsibility : Clare Saddington/
Adam Schofield
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Re-audit date |
October
2023 |
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Reference |
Rogers CL, Bain BJ, Fernandes S,
Garg M, Mooney C, Chiodini PL et al. British Society for Haematology guidelines
for the laboratory diagnosis of malaria. Br J Haematol 2022 (Epub ahead of print). |