Multicentre retrospective detection of nailfold videocapillaroscopy abnormalities in long covid patients, 2025, Ginaldi et al.

[Jonathan Edwards]

Why is this worth looking at in PwME whose ME didn't follow Covid? Isn't all this microcirculation stuff likely to be quite Covid-specific?

No, there have been a range of suggestions for vascular change sin ME/CFS. Some clinicians claim there are colour changes in hands and feet and several members have reported that. There have been studies suggesting changes in red cell deformability. The autonomic nervous system is implicated, which controls vascular calibre, if less so capillaries. And so on. A negative result is quite likely but that would suggest that ME/CFS can occur quite independently of any microvascular change, which might be an important lesson for Long Covid researchers focused on vessels and coagulation. And so on.

It is going back to the point that there are so few clues in ME/CFS anything like this is probably worth checking out. And since it is unbelievably low tech why not?

 

[EndME]

I just had contact with a former rheumatologist resident, now ME/CFS patient, in the Netherlands that has tried getting colleagues interested in setting up a nailfold capillaroscopy study in the past, unfortunately without any success. This person also has some expertise in capillaroscopy and would be able to get hold of a capillaroscope. They have let me know that they would have interest in joining such a project and that I have permission to share the above details.

 

[Sasha]

No, there have been a range of suggestions for vascular change sin ME/CFS. Some clinicians claim there are colour changes in hands and feet and several members have reported that. There have been studies suggesting changes in red cell deformability. The autonomic nervous system is implicated, which controls vascular calibre, if less so capillaries. And so on. A negative result is quite likely but that would suggest that ME/CFS can occur quite independently of any microvascular change, which might be an important lesson for Long Covid researchers focused on vessels and coagulation. And so on.

It is going back to the point that there are so few clues in ME/CFS anything like this is probably worth checking out. And since it is unbelievably low tech why not?

Thanks - that's all very interesting. I had thought that that red cell deformability stuff had gone in the bin.

Can we do anything to help make this study happen?

 

[Jonathan Edwards]

Can we do anything to help make this study happen?

Somebody might pick up on it from here. Word gets around. Not sure what more we can do.

 

[wigglethemouse]

I tried at home with a digital microscope but lighting and focus was really hard. A drop of mineral oil really helped make the capillaries stand out.
* Lighting from the microscope reflected back on the oil was quite harsh.
* Lighting from the side wasn't bright enough to give good contrast - the image reddened and so contrast was worse.
* The image on the screen looked reasonable. The resulting JPEG wasn't as good. Might have been movement to press the shutter took the image out of focus slightly or it could be the JPEG compression.
* At large magnification it was hard to focus. Digital zoom of the JPEG helped.

I didn't have enough clarity and zoom to create pictures like in this paper.

 

[Kitty]

I tried at home with a digital microscope but lighting and focus was really hard.

I tried to too, just out of curiosity.

My magnifier's only a cheap handheld one, and I found that using a 465nm UV torch, the sort you'd use to help identify minerals in rocks, made the blood vessels stand out more visibly than white light.

 

[Murph]

Here's my beginner attempt, just as proof of concept before I try to improve:

1. Methods: one human pinky finger, one digital microscope, one dab of oil (canola!), one smartphone to take a photo of the digital microscope screen, one assistant to hold the microscope stable while I used the phone.

definitely a few practical challenges in getting a good shot. Even still you can certainly see some capillaries, in my view they don't look like a row of neat hairpins, they may show some pathology?

I'm going to keep trying to refine my technique and when i find an sd card i should be able to use the actual microscope to take the photo, which will make matters better.

 

[wigglethemouse]

This was the best I could get - my issues were lighting and focus. Having an assistant to press the take photo button is a good idea. I tried a UV lamp but mine wasn't powerful enough. I also probably need to move to a bright room but I'm light sensitive...... Click to view.

 

[Murph]

This could be a good topic for a standalone thread, perhaps even an S4me "Citizen Science Project".

If we did do this we should specify in advance what the intent is?

Perhaps it could have three sub-goals: 1. determine feasibility of self-capillaroscopy. 2. get a rough feel for the extent of peculiar looking capillaries in a self-selecting, unblinded pwme population. (is there an ai you can feed pictures to and have them be classified?) 3. See if presence/absence of peculiarities shows any correlation with any other characteristics (e.g. POTS, age ,severity, duration, etc).

And the big goal would be to inform a hypothesis that could then be tested more formally on a well-defined, blinded, controlled group.

 

[EndME]

I see 2 approaches:

• We manage for somebody (say a junior rheumatologist together with a image technican) to pick this up from here and do things very rigorously. This would be preferred IMO.
• Otherwise: We see what can be done from home. There already exists literature on how these things can be done with a smarthphone, so I think that should be looked at first. I think the goal of this would be that this would be motivation enough for somebody to then hopefully follow the first approach.

I think in either case one will want researchers with some level of experience involved. I will contact the authors of the paper we are discussing here to see what they think. I will get back once they respond.

 

[Hutan]

Another nailfold study here (on patients with assorted autonomic dysfunction):
Signicant Microvascular Abnormalities Are Present in Autonomic Dysfunction: Results of a Prospective Study, Mumtaz, 2024

And there's this one, that was negative, but there were problems with patient selection
Baseline capillaroscopy provides no evidence of microvascular changes to predict long-COVID syndrome 2024 Ulusoy et al

 

[OrganicChilli]

Why is this worth looking at in PwME whose ME didn't follow Covid?

Why wouldn't it be? It seems more and more likely that we have different subgroups regardless of trigger.

 

[forestglip]

I realized my brother has a compound microscope, so I gave it a shot. I put a bit of fractionated coconut oil on my pinky and propped my phone up against the eyepiece. This is the best shot I could get. Probably not clear enough to make anything out, but just in case it's useful. (Click to enlarge)


Edit: Actually, I tried the next level of magnification and got some better shots:


Edit: I put the images in a photo editor and turned up contrast and gamma to make them clearer:


Edit: I also had a flashlight next to the microscope aimed at my finger. And I set my phone to automatically take photos every one second so I could adjust the focus with my free hand.

 

[darrellpf]

Nailfold issues are common in scleroderma, where Raynaud's is also very common. There is some good information about techniques in this article

https://pmc.ncbi.nlm.nih.gov/articles/PMC8922564/

 

[Sean]

They look good, @forestglip.

IIRC, formal medical photography uses standardised lighting, backgrounds, colour settings, perspectives, etc. May not need to go all the way, but do need to standardise variables like lighting, framing, size and resolution of image, etc, including a reference scale for size (e.g. 1mm), etc. But that doesn't seem too difficult.

 

[SNT Gatchaman]

I just had contact with a former rheumatologist resident, now ME/CFS patient, in the Netherlands that has tried getting colleagues interested in setting up a nailfold capillaroscopy study in the past, unfortunately without any success. This person also has some expertise in capillaroscopy and would be able to get hold of a capillaroscope. They have let me know that they would have interest in joining such a project and that I have permission to share the above details.

This is my first attempt at nailfold videocapillaroscopy. It's difficult to remove all motion. In my vast experience of <ahem> one case, I don't think this is normal. I'd be interested in comments from those with prior expertise here (@Jonathan Edwards) and off-forum (EndME's colleague) if possible.



I don't think we can upload short movies directly so here are some small zip archived "nail clippings" that you can hopefully view too.

 

[Jonathan Edwards]

I'd be interested in comments from those with prior expertise here (@Jonathan Edwards) and off-forum (EndME's colleague) if possible.

That looks normal to me. The loops are thin and straight and of good density. The images are very good. We did not see segmentation of the red cell train, which probably means that your exposure times are shorter. That might add a new aspect to the analysis.

 

[SNT Gatchaman]

We did not see segmentation of the red cell train, which probably means that your exposure times are shorter.

I can only post short video clips, but what about this one in centre-frame, screen-grabbed here?

 

[Jonathan Edwards]

I can only post short video clips, but what about this one in centre-frame, screen-grabbed here?

I think that is showing a normal, minimal calibre capillary that may have slow flow for temperature reasons and so there is some red cell clumping apparent.

 

[SNT Gatchaman]

Thank you, that's both interesting and more than a little reassuring. My most recent employment eye assessment had also shown perfect retinal capillary appearances.

The technique itself looks relatively straightforward and the only thing I'm unable to do currently is make measurements with a scale as were shown in this paper. So constrained to morphology assessment I guess.

I'll try and look at a friend with longer-term pre-Covid ME/CFS and another with post-Covid cardiac issues (suspected microcirculatory) but without PEM later on this weekend.