Microscopy and RDT test sensitivity - Revision history

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2024-09-24T08:55:18Z

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	~~'''Navigation'''</br>~~
	~~[[Rapid diagnostic tests (RDTs)\|Go Back]]~~
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	~~{\| class="wikitable" style="border-style: solid; border-width: 4px; color:black"~~
	~~\|colspan="1" style = "font-size:100%; color:black; background: FFFAFA"\|<span style="color:navy>'''The value of RDT compared with microscopy: thick blood films'''</span>~~


	<span style="font-size:90%">In ideal conditions a well-trained microscopist with experience in malaria, viewing a well-prepared thick blood film using a good quality microscope may detect better than 1 infected cell per 1000 total red cells. This is equivalent to around 50 parasites/ul. However, in practice it is estimated that a less experienced microscopist in equivalent conditions may acheive less sensitivity - perhaps 1 parasite in 100 red cells - equivalent to 500 parasites/μl. Both these outcomes are as good or better than an RDT test for detecting ''P.falciparum'', and exceed what might be expected for other malaria species.</span>

	<span style="font-size:90%">In less ideal conditions where equipment, staining quality, or microscopic experience is less good, then RDTs may have equivalent or superior sensitivity to microscopy. This includes many malarial endemic regions where this sensitivity will not be achieved. It is important in these conditions however to understand the limitations of the selected test in terms of species identiication and sensitivity.</span>

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	~~<span style="color:navy>'''The value of RDT tests compared with microscopy: thin blood films'''</span>~~

	<span style="font-size:90%">Thin films may provide similar sensitivity to a routine laboratory for an experienced morphologist with sufficient time and following recommended practices. Many people are more familiar with thin films and feel more comfortable with this approach, although it is not the currently recommended practice. Thin films however offer some advantages:</span>

	*<span style="font-size:90%">Species may be identified much more confidently using thin films (including mixed infectionz)</span>
	*<span style="font-size:90%">The % of red cells infected by parasites is much more accurately assessed by thin film.</span>

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	~~<span style="color:navy>'''Summing up'''</span>~~

	<span style="font-size:90%">RDT tests are less affected by operator skill, facilities or training and may be as good or better than morphology where expertise is limited or conditions do not allow microscopy. RDTs also provide a more rapid turnaround time and when used together with morphology may help increase diagnostic confidence. However, operators must be aware of test limitations.</br></br>Morphology has a superior achievable sensitivity for all malaria species, and particularly for lower levels of parasite infection and for some species. Outcomes are however highly dependent on the quality of preparation, the facilities available to examine the film, and the skill of the operator. Morphology provides additional advantages of: allowing the % parasite infection to be assessed and are unaffected by problems of gene deletion.</br></span>

Admin at 14:35, 9 September 2024

2024-09-09T14:35:41Z

← Older revision		Revision as of 15:35, 9 September 2024
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	In ideal conditions a well-trained microscopist with experience in malaria, viewing a well-prepared thick blood film using a good quality microscope may detect better than 1 infected cell per 1000 total red cells. This is equivalent to around 50 parasites/ul. However, in practice it is estimated that a less experienced microscopist in equivalent conditions may acheive less sensitivity - perhaps 1 parasite in 100 red cells - equivalent to 500 parasites/μl. Both these outcomes are as good or better than an RDT test for detecting ''P.falciparum'', and exceed what might be expected for other malaria species.		<span style="font-size:90%">In ideal conditions a well-trained microscopist with experience in malaria, viewing a well-prepared thick blood film using a good quality microscope may detect better than 1 infected cell per 1000 total red cells. This is equivalent to around 50 parasites/ul. However, in practice it is estimated that a less experienced microscopist in equivalent conditions may acheive less sensitivity - perhaps 1 parasite in 100 red cells - equivalent to 500 parasites/μl. Both these outcomes are as good or better than an RDT test for detecting ''P.falciparum'', and exceed what might be expected for other malaria species.</span>

	In less ideal conditions where equipment, staining quality, or microscopic experience is less good, then RDTs may have equivalent or superior sensitivity to microscopy. This includes many malarial endemic regions where this sensitivity will not be achieved. It is important in these conditions however to understand the limitations of the selected test in terms of species identiication and sensitivity.		<span style="font-size:90%">In less ideal conditions where equipment, staining quality, or microscopic experience is less good, then RDTs may have equivalent or superior sensitivity to microscopy. This includes many malarial endemic regions where this sensitivity will not be achieved. It is important in these conditions however to understand the limitations of the selected test in terms of species identiication and sensitivity.</span>

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	<span style="color:navy>'''The value of RDT tests compared with microscopy: thin blood films'''</span>		<span style="color:navy>'''The value of RDT tests compared with microscopy: thin blood films'''</span>

	Thin films may provide similar sensitivity to a routine laboratory for an experienced morphologist with sufficient time and following recommended practices. Many people are more familiar with thin films and feel more comfortable with this approach, although it is not the currently recommended practice. Thin films however offer some advantages:		<span style="font-size:90%">Thin films may provide similar sensitivity to a routine laboratory for an experienced morphologist with sufficient time and following recommended practices. Many people are more familiar with thin films and feel more comfortable with this approach, although it is not the currently recommended practice. Thin films however offer some advantages:</span>

	*Species may be identified much more confidently using thin films (including mixed infectionz)		*<span style="font-size:90%">Species may be identified much more confidently using thin films (including mixed infectionz)</span>
	*The % of red cells infected by parasites is much more accurately assessed by thin film		*<span style="font-size:90%">The % of red cells infected by parasites is much more accurately assessed by thin film.</span>

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	<span style="color:navy>'''Summing up'''</span>		<span style="color:navy>'''Summing up'''</span>

	RDT tests are less affected by operator skill, facilities or training and may be as good or better than morphology where expertise is limited or conditions do not allow microscopy. RDTs also provide a more rapid turnaround time and when used together with morphology may help increase diagnostic confidence. However, operators must be aware of test limitations.		<span style="font-size:90%">RDT tests are less affected by operator skill, facilities or training and may be as good or better than morphology where expertise is limited or conditions do not allow microscopy. RDTs also provide a more rapid turnaround time and when used together with morphology may help increase diagnostic confidence. However, operators must be aware of test limitations.</br></br>Morphology has a superior achievable sensitivity for all malaria species, and particularly for lower levels of parasite infection and for some species. Outcomes are however highly dependent on the quality of preparation, the facilities available to examine the film, and the skill of the operator. Morphology provides additional advantages of: allowing the % parasite infection to be assessed and are unaffected by problems of gene deletion.</br></span>


	Morphology has a superior achievable sensitivity for all malaria species, and particularly for lower levels of parasite infection and for some species. Outcomes are however highly dependent on the quality of preparation, the facilities available to examine the film, and the skill of the operator. Morphology provides additional advantages of: allowing the % parasite infection to be assessed and are unaffected by problems of gene deletion.</br>

Admin at 14:33, 9 September 2024

2024-09-09T14:33:47Z

← Older revision		Revision as of 15:33, 9 September 2024
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	{\| class="wikitable" style="border-style: solid; border-width: 4px; color:black"		{\| class="wikitable" style="border-style: solid; border-width: 4px; color:black"
	\|colspan="1" style = "font-size:~~110~~%; color:black; background: FFFAFA"\|<span style="color:navy>'''The value of RDT compared with microscopy: thick blood films'''</span>		\|colspan="1" style = "font-size:100%; color:black; background: FFFAFA"\|<span style="color:navy>'''The value of RDT compared with microscopy: thick blood films'''</span>

Admin at 14:32, 9 September 2024

2024-09-09T14:32:59Z

← Older revision		Revision as of 15:32, 9 September 2024
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	RDT tests are less affected by operator skill, facilities or training and may be as good or better than morphology where expertise is limited or conditions do not allow microscopy. RDTs also provide a more rapid turnaround time and when used together with morphology may help increase diagnostic confidence. However, operators must be aware of test limitations.		RDT tests are less affected by operator skill, facilities or training and may be as good or better than morphology where expertise is limited or conditions do not allow microscopy. RDTs also provide a more rapid turnaround time and when used together with morphology may help increase diagnostic confidence. However, operators must be aware of test limitations.

	Morphology: has a superior achievable sensitivity for all malaria species ~~but~~ particularly for ~~low~~ levels of parasite infection ~~these outcomes~~ are highly dependent on the quality of preparation, the facilities available to examine the film, and the skill of the operator.
	~~RDTs~~		Morphology has a superior achievable sensitivity for all malaria species, and particularly for lower levels of parasite infection and for some species. Outcomes are however highly dependent on the quality of preparation, the facilities available to examine the film, and the skill of the operator. Morphology provides additional advantages of: allowing the % parasite infection to be assessed and are unaffected by problems of gene deletion.</br>
	~~Allow~~ parasite ~~level~~ to be ~~detected.~~
	~~Disadvantages compared with blood:~~
	~~False negatives and poor at some species~~
	and are unaffected by problems of gene deletion ~~or poorly-detected species~~.

Admin at 14:29, 9 September 2024

2024-09-09T14:29:39Z

← Older revision		Revision as of 15:29, 9 September 2024
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	In ideal conditions a well-trained microscopist with experience in malaria, viewing a well-prepared thick blood film using a good quality microscope may detect better than 1 infected cell per 1000 total red cells. This is equivalent to around 50 parasites/ul. However, in practice it is estimated that a less experienced microscopist in equivalent conditions may acheive less sensitivity - perhaps 1 parasite in 100 red cells - equivalent to 500 parasites/μl. Both these outcomes are as good or better than an RDT test for detecting ''P.falciparum'', and exceed what might be expected for other malaria species.		In ideal conditions a well-trained microscopist with experience in malaria, viewing a well-prepared thick blood film using a good quality microscope may detect better than 1 infected cell per 1000 total red cells. This is equivalent to around 50 parasites/ul. However, in practice it is estimated that a less experienced microscopist in equivalent conditions may acheive less sensitivity - perhaps 1 parasite in 100 red cells - equivalent to 500 parasites/μl. Both these outcomes are as good or better than an RDT test for detecting ''P.falciparum'', and exceed what might be expected for other malaria species.

	In less ideal conditions where equipment, staining quality, or microscopic experience is less good, then RDTs may have equivalent or superior sensitivity to microscopy. ~~However, it~~ is important in these conditions to understand the limitations of the selected test in terms of species identiication and sensitivity.		In less ideal conditions where equipment, staining quality, or microscopic experience is less good, then RDTs may have equivalent or superior sensitivity to microscopy. This includes many malarial endemic regions where this sensitivity will not be achieved. It is important in these conditions however to understand the limitations of the selected test in terms of species identiication and sensitivity.

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	<span style="color:navy>'''~~Conclusions~~'''</span>		<span style="color:navy>'''Summing up'''</span>

	~~and~~ are ~~unaffected~~ by ~~problems of gene deletion~~ or ~~poorly-detected species~~. ~~Allow parasite level to~~ be ~~detected~~.		RDT tests are less affected by operator skill, facilities or training and may be as good or better than morphology where expertise is limited or conditions do not allow microscopy. RDTs also provide a more rapid turnaround time and when used together with morphology may help increase diagnostic confidence. However, operators must be aware of test limitations.
	~~Achievable~~ sensitivity: these outcomes are highly dependent on the quality of preparation, the facilities available to examine the film, and the skill of the operator~~. In many malarial endemic regions this sensitivity will not be achieved~~.
			Morphology: has a superior achievable sensitivity for all malaria species but particularly for low levels of parasite infection these outcomes are highly dependent on the quality of preparation, the facilities available to examine the film, and the skill of the operator.
	RDTs		RDTs
	~~Less affected by operator skill, facilities or training: may~~ be ~~at least as good as morphology where expertise is limited. Provide a more rapid turnaround time~~.		Allow parasite level to be detected.
	Disadvantages compared with blood:		Disadvantages compared with blood:
	False negatives and poor at some species		False negatives and poor at some species
			and are unaffected by problems of gene deletion or poorly-detected species.

Admin at 14:23, 9 September 2024

2024-09-09T14:23:15Z

← Older revision		Revision as of 15:23, 9 September 2024
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	In less ideal conditions where equipment, staining quality, or microscopic experience is less good, then RDTs may have equivalent or superior sensitivity to microscopy. However, it is important in these conditions to understand the limitations of the selected test in terms of species identiication and sensitivity.		In less ideal conditions where equipment, staining quality, or microscopic experience is less good, then RDTs may have equivalent or superior sensitivity to microscopy. However, it is important in these conditions to understand the limitations of the selected test in terms of species identiication and sensitivity.

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	<span style="color:navy>'''The value of RDT compared with microscopy: thin blood films'''</span>		<span style="color:navy>'''The value of RDT tests compared with microscopy: thin blood films'''</span>

	Thin films may provide similar sensitivity to a routine laboratory for an experienced morphologist with sufficient time and following recommended practices. Many people are more familiar with thin films and feel more comfortable with this approach, although it is not the currently recommended practice. Thin films however offer some advantages:		Thin films may provide similar sensitivity to a routine laboratory for an experienced morphologist with sufficient time and following recommended practices. Many people are more familiar with thin films and feel more comfortable with this approach, although it is not the currently recommended practice. Thin films however offer some advantages:

	*Species may be identified much more confidently using ~~tin~~ films (including mixed infectionz)		*Species may be identified much more confidently using thin films (including mixed infectionz)
	*The % of red cells infected by parasites is much more ~~accurate~~ by thin film		*The % of red cells infected by parasites is much more accurately assessed by thin film

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Admin at 14:22, 9 September 2024

2024-09-09T14:22:09Z

← Older revision		Revision as of 15:22, 9 September 2024
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	~~'''~~In ideal conditions~~: ''' A~~ well-trained microscopist with experience in malaria, viewing a well-prepared thick blood film using a good quality microscope may detect better than 1 infected cell per 1000 total red cells. This is equivalent to around 50 parasites/ul. However, in practice it is estimated that a less experienced microscopist in equivalent conditions may acheive less sensitivity - perhaps 1 parasite in 100 red cells - equivalent to 500 parasites/μl. Both these outcomes are as good or better than an RDT test for detecting ''P.falciparum'', and exceed what might be expected for other malaria species.		In ideal conditions a well-trained microscopist with experience in malaria, viewing a well-prepared thick blood film using a good quality microscope may detect better than 1 infected cell per 1000 total red cells. This is equivalent to around 50 parasites/ul. However, in practice it is estimated that a less experienced microscopist in equivalent conditions may acheive less sensitivity - perhaps 1 parasite in 100 red cells - equivalent to 500 parasites/μl. Both these outcomes are as good or better than an RDT test for detecting ''P.falciparum'', and exceed what might be expected for other malaria species.


	~~'''~~In less ideal conditions~~:''' If~~ equipment, staining quality, or microscopic experience is less good, then RDTs may have equivalent or superior sensitivity to microscopy. However, it is important in these conditions to understand the limitations of the selected test in terms of species identiication and sensitivity.		In less ideal conditions where equipment, staining quality, or microscopic experience is less good, then RDTs may have equivalent or superior sensitivity to microscopy. However, it is important in these conditions to understand the limitations of the selected test in terms of species identiication and sensitivity.

Admin at 14:21, 9 September 2024

2024-09-09T14:21:21Z

@@ Line 17: / Line 17: @@
 <span style="color:navy>'''The value of RDT compared with microscopy: thin blood films'''</span>
-Thin films may provide similar sensitivity to a routine laboratory for an experienced morphologist with sufficient time and following recommended practices. Many people are more familiar with thin films and feel more comfortable with this approach, although it is not the currently recommended practice.  are examined but this is time consuming. Thin films identify all species and allow species recognition including mixed infection and are unaffected by problems of gene deletion or poorly-detected species. Allow parasite level to be detected.
+Thin films may provide similar sensitivity to a routine laboratory for an experienced morphologist with sufficient time and following recommended practices. Many people are more familiar with thin films and feel more comfortable with this approach, although it is not the currently recommended practice. Thin films however offer some advantages:
 Achievable sensitivity:  these outcomes are highly dependent on the quality of preparation, the facilities available to examine the film, and the skill of the operator. In many malarial endemic regions this sensitivity will not be achieved.
 RDTs
@@ Line 23: / Line 32: @@
 Disadvantages compared with blood:
 False negatives and poor at some species

Admin at 14:17, 9 September 2024

2024-09-09T14:17:53Z

← Older revision		Revision as of 15:17, 9 September 2024
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	<span style="color:navy>'''The value of RDT compared with microscopy: ~~thick~~ blood films'''</span>		<span style="color:navy>'''The value of RDT compared with microscopy: thin blood films'''</span>

	~~Compare with RDTs:~~		Thin films may provide similar sensitivity to a routine laboratory for an experienced morphologist with sufficient time and following recommended practices. Many people are more familiar with thin films and feel more comfortable with this approach, although it is not the currently recommended practice. are examined but this is time consuming. Thin films identify all species and allow species recognition including mixed infection and are unaffected by problems of gene deletion or poorly-detected species. Allow parasite level to be detected.
	~~P.falciparum is identified in the range x-y.~~
	~~Non-falciparum species are identified in the range x-y~~
	~~Other advantages: thin:~~ may provide similar sensitivity to a routine ~~lab if~~ sufficient ~~cells~~ are examined but this is time consuming. Thin films identify all species and allow species recognition including mixed infection and are unaffected by problems of gene deletion or poorly-detected species. Allow parasite level to be detected.
	Achievable sensitivity: these outcomes are highly dependent on the quality of preparation, the facilities available to examine the film, and the skill of the operator. In many malarial endemic regions this sensitivity will not be achieved.		Achievable sensitivity: these outcomes are highly dependent on the quality of preparation, the facilities available to examine the film, and the skill of the operator. In many malarial endemic regions this sensitivity will not be achieved.
	RDTs		RDTs

Admin at 14:13, 9 September 2024

2024-09-09T14:13:58Z

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			<span style="color:navy>'''The value of RDT compared with microscopy: thick blood films'''</span>

	Compare with RDTs:		Compare with RDTs: