Sept 09: Blood Film Challenge

Re: Blood Film Challenge

Martin Atkinson — Fri, 20 Aug 2010 17:33:51 GMT

[quote user="Bob Russell"]

I would be 'happy' to tell the owner that I think it is a form of leukaemia and we should wait for confirmation of type before progressing further with treatment options. My microscope is a little limited in its capabilities and it is a little hard to justify up to £1000 for a good one at my level!!!!

[/quote]

I was about to vote but then realised the thread was year old but I got it right so I'm chuffed. I think we should all be able to do a differential WBC and be able to spot abnormal cells and classify an anaemia, it can save lives while waiting for lab results. IMO the biggest barrier to interpreting slides is not the cost of the microscope but quality of smears - most vets make them too thick. But anyway Graham what happened to this being the first of a monthly series or am I missing something?

Re: Blood Film Challenge

Bob Russell — Thu, 19 Aug 2010 11:56:04 GMT

Re: Blood Film Challenge

Colin Cameron — Thu, 19 Aug 2010 10:37:13 GMT

[quote user="Jillian Hall"]on a not infrequent basis.[/quote]

Do you actually mean "not infrequently" See fun thread on adjectives as nouns!

Re: Sept 09: Blood Film Challenge

Roberta Prina — Wed, 13 Jan 2010 21:58:19 GMT

[quote user="Arlo Guthrie"]

The following question submitted by Graham Bilbrough at IDEXX is the first of what I hope will become a monthly series of interactive clinical challenges / case study discussions.[/quote]

This is a very interesting thread! Any chance that we can have more haematology quizzes?

Re: Blood Film Challenge

pete coleshaw — Mon, 19 Oct 2009 09:47:20 GMT

[quote user="Graham Bilbrough"]These latter cells are morphologically more consistent with monocytic lineage. With close inspection of this abnormal circulating cell population, there appears to be a gradual transition between the extremes of these two morphologic presentations and nuclear chromatin patterns are similar in all forms. These findings are more supportive of monocytic lineage; however, special staining (enzyme cytochemical characterization) and immunophenotype characterization are required for definitive cell-of-origin identification. Myelo-monocytic leukemia should be considered still in the differential; however, the finding of morphologically normal appearing mature neutrophils without evidence of any morphologic transition to the predominating immature mononuclear cell population is relatively strong support evidence against both myeloid and myelo-monocytic leukemia.[/quote]

confirms what I guess most of us are now saying - send it to a competent haematologist

I was torn between the indented nuclei being monocytic or a variation of the single leukemic cell population - but now I've read the above I realise I cannot realistically have been expected to be able to tell any way!

hey ho

Re: Blood Film Challenge

Jillian Hall — Sat, 17 Oct 2009 15:01:05 GMT

I also recognised leukaemia, but what type was pretty much a guess (an an incorrect one).

I think that the biggest first step in making an interpretation of this or any abnormal smear is having a good appreciation of what is normal. If someone's not looked at enough smears to know what variants of normal exist then they're not going to be bleo to make a confident diagnosis of "abnormal".

I would assume that those of us who are interested enough to participate in this forum are the sorts of people that look at blood smear on a not infrequent basis. The biggest danger of misdiagnosis will come from those of us who don't look down a microscope all year, then look at the smear from that anaemic dog at 6.30 on Friday because they have no other choice.

Re: Blood Film Challenge

Niall Taylor — Fri, 16 Oct 2009 16:11:58 GMT

[quote user="Clive Ansell"]

ok. I knew it was a leukaemia rather than inflammatory, so that will do for me - I'm not a haematologist or pathologist.

[/quote]

That's a pretty good opinion to be able to give clients at a practitioner level, so long as they understand that a 2nd opinion would be needed for greater certainty. Knowing the difference between a possible cancer and inflammation would give clients the chance to prepare themselves for what might lie ahead.

Cheers,

Niall

Re: Blood Film Challenge

Hannah Wynne Richards — Fri, 16 Oct 2009 10:12:12 GMT

Like Gillian, I got it right, but admit to a certain amount of "eenie, meenie, miny mo "

Wynne

Re: Blood Film Challenge

Clive Ansell — Wed, 14 Oct 2009 17:20:03 GMT

ok. I knew it was a leukaemia rather than inflammatory, so that will do for me - I'm not a haematologist or pathologist.

Re: Blood Film Challenge

Gillian Mostyn — Wed, 14 Oct 2009 16:47:54 GMT

(More luck than judgement - but don't tell anyone else will you? )

Re: Blood Film Challenge

Clive Ansell — Wed, 14 Oct 2009 16:43:18 GMT

Thanks - got it wrong though , a dusty bin for me I guess

Re: Blood Film Challenge

Gillian Mostyn — Wed, 14 Oct 2009 15:49:41 GMT

Look back at the quiz - your answer is at the bottom!

I got it right! Do I get a gold star??

Re: Blood Film Challenge

Clive Ansell — Wed, 14 Oct 2009 13:02:53 GMT

I can't remember which I voted for now!

I was able to tell it was a leukaemia as opposed to an inflamatory leukogram, but that was as far as my skills and thought would take me

Re: Blood Film Challenge

Graham Bilbrough — Wed, 14 Oct 2009 12:31:22 GMT

Okay. Here it is then. I should emphasize that these are not my words (they come from someone clever!).

C. Acute monocytic leukaemia

In reality, a definitive answer is not possible without further investigation.

Regarding the best working differential, leukaemia is the best answer. The specific type of leukaemia requires characterization of the large mononuclear cells representing the leukaemic cell population. Many of these cells are immature--appearing, large mononuclear cells with slightly peripherally located, rounded nuclei. A moderate amount of moderately blue staining cytoplasm with no distinguishing granules is present. These cells morphologically are most consistent with lymphocytic lineage. However, moderate numbers of these cells with similar size and cytoplasmic features have slightly indented to more irregularly shaped nuclei. These latter cells are morphologically more consistent with monocytic lineage. With close inspection of this abnormal circulating cell population, there appears to be a gradual transition between the extremes of these two morphologic presentations and nuclear chromatin patterns are similar in all forms. These findings are more supportive of monocytic lineage; however, special staining (enzyme cytochemical characterization) and immunophenotype characterization are required for definitive cell-of-origin identification. Myelo-monocytic leukemia should be considered still in the differential; however, the finding of morphologically normal appearing mature neutrophils without evidence of any morphologic transition to the predominating immature mononuclear cell population is relatively strong support evidence against both myeloid and myelo-monocytic leukemia.

Evidence against inflammatory disease is based on the distribution of the leukocytes present, not based on the degree of leukocytosis. Although extremely uncommon, we can see inflammatory leukograms with greater than 150,000/µL; these are often identified as "leukemoid reactions." In this particular case, greater than 95% of the leukocytes in circulation represent the large immature mononuclear cell population. The "normal" inflammatory leukocytes are in the minority and in this case, neutrophils are low--normal in number.

Final Diagnosis

Acute monocytic leukaemia based on immunophenotyping and special stains.

Re: Blood Film Challenge

Arlo Guthrie — Wed, 14 Oct 2009 11:53:02 GMT

[quote user="Graham Bilbrough"] As for the quiz, well, that was my idea of fun. Arlo, when do you want the answer posted?[/quote]

Think that probably most people who wanted to answer the question have done, so it's time for the answer..

Re: Blood Film Challenge

Laurence Webb — Fri, 09 Oct 2009 08:59:07 GMT

[quote user="alex gough"]I'm sure you know this, but just be aware when you are diagnosing an acute anaemia with a pcv of 12 and there is no evidence of regeneration, that this may be pre-regenerative. [/quote]

Yes, I did. I was just trying to keep the example short to demonstrate why an ability to perform a basic smear exam is useful at 6.30pm on Friday. I generally assume that a dog with a PCV of 12 that walks in wagging its tail hasn't had that fall occur in the last 24 hours and one other clue to differentiating pre-regenerative from non-regenerative is asking the owner how long the dog's been unwell!

Re: Blood Film Challenge

pete coleshaw — Fri, 09 Oct 2009 08:30:18 GMT

[quote user="Graham Bilbrough"]I believe that all vets and veterinary nurses--yes, I know, I live in an ivory tower--should be able to look at a blood smear, confidently spot normal and get some useful clues for their emergency cases (spherocytes, Heniz bodies...). I[/quote]

I'll go with that graham - like I say, I do like looking myself - my concern is is not what people know - it's what they dont know which is potentially dangerous.

Re: Blood Film Challenge

Alex Gough — Thu, 08 Oct 2009 16:14:35 GMT

[quote user="Laurence Webb"]A dog with a PCV of 12 that is non-regenerative has a much worse prognosis than one that is regenerative and some owners may choose to euthanase on the basis of poorer prognosis.[/quote]

I'm sure you know this, but just be aware when you are diagnosing an acute anaemia with a pcv of 12 and there is no evidence of regeneration, that this may be pre-regenerative. It can take up to 5 days, and even longer in some cases for regeneration to start, so if this is an acute haemolytic anaemia then it will appear non-regenerative unless it is an acute on chronic presentation. Bilirubin levels can be useful, but one good rule of thumb in dogs that present with very low pcvs for the first time is how ill they are. Dogs that have non-regenerative anaemia tend to have had a slowly falling PCV for a long time, as the red cells arent being lost at an accelerated rate, they are just failing to be replaced. Consequently, the body has more time to adjust its haemoglobin curve, eg with changing 2,3 DPG levels, and can cope better with the lower PCV. So paradoxically, because as you say non-regenerative anaemias have a poorer prognosis than regenerative or pre-regenerative anaemias, a sick, weak dog with a pcv of 12 may have a better long term prognosis than a bright happy one with the same pcv, provided you can get it through the acute crisis. Obviously not a certainty for all cases, just a useful extra piece of the jigsaw puzzle.

Alex

Re: Blood Film Challenge

Mike Martin — Thu, 08 Oct 2009 14:29:41 GMT

[quote user="Laurence Webb"]I think that it is useful to be able to look at a blood smear and get some idea what is going on so that immediate treatment can be given (or at least not giving inappropriate treatment) whilst you are waiting for a pathologist's interpretation. [/quote]

[quote user="Graham Bilbrough"]There is no expectation that we can create haematologists, rather to encourage vets to use their microscope for some quick answers and to remain reliant on a reference laboratory for support.[/quote]

Yes. Fair points.

And I guess the same is about any diagnostic, eg ECG or x-ray reading, we can't always have everything interpreted by an expert. So I guess we need to know our own limits.

Re: Blood Film Challenge

Gillian Mostyn — Thu, 08 Oct 2009 12:43:42 GMT

mee too.

Re: Blood Film Challenge

Hannah Wynne Richards — Thu, 08 Oct 2009 12:32:16 GMT

I would definitely like to know the correct answer !

Wynne

Re: Blood Film Challenge

Graham Bilbrough — Thu, 08 Oct 2009 12:10:25 GMT

I believe that all vets and veterinary nurses--yes, I know, I live in an ivory tower--should be able to look at a blood smear, confidently spot normal and get some useful clues for their emergency cases (spherocytes, Heniz bodies...). In particular, for those using in-clinic haematology analysers, if you want a full blood count, you _must_ spend 3 to 4 minutes looking at a blood smear and/or send the smear to a reference lab.

If you want to know more about how to look at a blood smear in 3 to 4 minutes, take a look at this training webinar.

Evaluate Your Blood Film in Less than 3 Minutes
http://idexx.na3.acrobat.com/p96174723/

There is no expectation that we can create haematologists, rather to encourage vets to use their microscope for some quick answers and to remain reliant on a reference laboratory for support.

As for the quiz, well, that was my idea of fun. Arlo, when do you want the answer posted?

All the best

Graham

Re: Blood Film Challenge

Laurence Webb — Thu, 08 Oct 2009 11:01:21 GMT

I think that it is useful to be able to look at a blood smear and get some idea what is going on so that immediate treatment can be given (or at least not giving inappropriate treatment) whilst you are waiting for a pathologist's interpretation.

I always say to owners that this is only my opinion and that I need a pathologist's interpretation before drawing any firm conclusions so I would never view in-house film reading as a substitute for a qualified haematologist.

Typically anaemic dogs turn up at 6.30pm on fridays and it's helpful to be able to get a preliminary idea if it's regenerative/non-regenerative and if it's got spherocytes or not. A dog with a PCV of 12 that is non-regenerative has a much worse prognosis than one that is regenerative and some owners may choose to euthanase on the basis of poorer prognosis. Similarly if you can say to an owner 'I think this blood has got neoplastic cells in it' then they get a chance to consider how they want to proceed whilst you are waiting for confirmation to come back.

Just make it clear that this is your suspicion rather than a definate diagnosis, then bung them some steroids!

Re: Blood Film Challenge

Mike Martin — Thu, 08 Oct 2009 09:34:24 GMT

[quote user="pete coleshaw"]I cannot understand this idea concept of training yourself / your nurse to read blood films - if it takes a pathologist 3 years to learn, how can we expect to be copmpetent after a brief course.[/quote]

I agree whole-heartedly.

Is it worth the risk in getting it badly wrong? What risk? For me, its my own conscience.

Re: Blood Film Challenge

Hannah Wynne Richards — Thu, 08 Oct 2009 09:09:42 GMT

Hello Pete

Long time, no see

You've hit the nail on the head. I wouldn't attempt to go further than that WBC count must be leukaemia, and the cells certainly look odd-time to hand over to a clinical pathologist

Wynne