Akira Kawahima wrote:

Dear IANS Team,

Thank you very much for organizing the Virtual Standard HRA Course — it has been an incredibly valuable learning experience.

I would like to ask a question regarding the use of Lugol’s iodine solution in high-resolution anoscopy (HRA):

• Does the concentration of Lugol’s iodine vary depending on the institution or practitioner?
• If so, are there differences in diagnostic effectiveness based on the concentration used?

I would be grateful if you could share any recommendations, standards, or published guidance regarding the preferred Lugol’s iodine formulation for anal HRA (e.g., 2%, 3%, 5%).

Thank you for your time and support.

Warm regards,

Akira Kawashima

PhD Program, Kumamoto University, Japan

Lugol's solution consists of a mixture of 5% iodine and 10% potassium iodide. THe most common strength used both in HRA and gynecology is 5% Lugol's Strong Iodine. Much of the literature that discusses use of Lugol's does not provide a percentage, presumably because the 5% is so common. When the methods section does include the percentage it is always 5% (for example https://pubmed.ncbi.nlm.nih.gov/34573940/). There have been shortages of Lugol's reported on occasion and sometimes providers have had to use other formulations such as ½ strength which is 2.5%. This is a comprehensive review of Lugol's in gynecology. The only article discussing Lugol's in HRA is https://pubmed.ncbi.nlm.nih.gov/26640825/ but even here we did include the Lugol's strength (which was 5%).

https://www.sciencedirect.com/science/article/abs/pii/S030121152100172X

Naomi Jay

Thank you for participating in the course! In general we have a low threshold for biopsies because it is difficult to exclude HSIL based on visualization alone. I do think your approach  to perform biopsies on everything that is acetowhite and lugol’s negative is reasonable, however, you will have to balance your goal of being thorough with patient ability to tolerate a longer exam with more biopsies. I would, as you go along, aim to discern whether there are particular characteristics that are more suggestive of HSIL in these acetowhite and lugol’s negative areas given that it may not be logistically feasible to biopsy everything you see. Vascular changes like mosaic pattern or atypical vessels are particularly suggestive of HSIL and can help you prioritize. Most HSIL will have vascular changes. If you aren't seeing any vascular changes consider whether you are using high enough magnification and enough acetic acid for the vasculaity to appear. Also, document the different findings and then compare to when you get the pathology results. Review the pictures and compare those that were HSIL with those that weren't.  This will help you hone your sklls for differentiating HSIL from non-HSIL. 

Cristina Brickman
Coure Director

Dear IANS Team,

Thank you very much for organizing the Virtual Standard HRA Course — it has been an incredibly valuable learning experience.

I would like to ask a question regarding the use of Lugol’s iodine solution in high-resolution anoscopy (HRA):

• Does the concentration of Lugol’s iodine vary depending on the institution or practitioner?
• If so, are there differences in diagnostic effectiveness based on the concentration used?

I would be grateful if you could share any recommendations, standards, or published guidance regarding the preferred Lugol’s iodine formulation for anal HRA (e.g., 2%, 3%, 5%).

Thank you for your time and support.

Warm regards,

Akira Kawashima

PhD Program, Kumamoto University, Japan

How long do the changes in colour last with acetic acid and with Lugol's, respectively?