as far as i know - the same issue does not exist with rifabutin - at least i have never read anything to suggest it
to aid your discussions with your LLMD - here is an example of such a report in the scientific literature
report said...
Although rare, several reports have been published describing the post‐rifampicin acute renal failure dating back to 1976. 2 Most commonly manifesting as acute tubular necrosis (ATN) following re‐administration of rifampicin;
source:
https://www.ncbi.nlm.nih.gov/pmc/articles/pmc9771787/in their defence - although very serious - and can lead to permanent kidney damage - it is a rare event - so your LLMD may have treated many lyme patients with pulsed Rifampicin and never seen this happen before - and so it may appear safe to them based on their experience.
i don't think its a case of never taking it again in your life if you have ever taken it - the risk of the reaction likely reduces the more time has passed since the last administration.
although rare, some people even get this reaction when taking rifampicin for the first time - it just seems that the risk goes up if you take the drug in a pulsed fashion.
in terms of putting this risk in perspective - its worth bearing in mind that there are risks associated with taking any drug and other drugs are capable of causing the same reaction.
so doctors do not have a zero risk option to choose - all options have some risk - and the doctors must instead perform a risk vs benefit calculation on behalf of the patient.
i hope its of some help