What causes recuring UTI in elderly?

Hello doctor,

My 90-year-old mother suffers from UTI and takes Xarelto. Due to uncontrollable bleeding, the medication was stopped for a few days. She also suffered from uncontrolled diarrhea due to the use of Nitro. She then used, Bactrim single strength two to three times a week with 1000 mg Mannose and 500mg slow-release Vitamin C on alternative days. She also has been resistant to Bactrim a few years ago but not currently.

I also performed regular dipstick tests to diagnose the UTI. I have also attached lab results that were negative for nitrites. It appears to be vaginal contamination based on the lab's diagnosis, and the urine culture identified later more than three organisms and resample if needed.

She also applied Premarin cream 48 hours before giving the sample. Kindly help me by answering the following questions.

1. What is the significance of the lab report and any denoted parameter?

2. Is the calcium oxalate caused by the vitamin C?

3. If she has to develop a breakthrough UTI, is it better to treat it with a higher dose of Bactrim?

4. Can Fosfomycin be used as a preventive medication?

Thank you.

Hello doctor,

Thank you for the reply.

My mother takes daily urinalysis strips. No nitrites or leukocytes were identified later this week. She got a single strength every other day for the last six months, and everything was satisfactory except there was a trace of RBCs in two samples. She also takes vitamin C 500mg of ascorbic acid four to five times a week. I am submitting another urine sample report which was taken yesterday. Kindly help in interpreting the results.

Thank you.

Hello doctor,

Thank you for the reply.

My mother has a personal care worker to clean my mother's breast fold area twice daily, and the use of Clotrimazole and tea tree oil has significantly reduced the redness in the last few days. The Bactrim has minimum side effects, and the skin fungus is a secondary problem. I will be submitting the lab urinalysis or culture within the necessary time frame. Kindly suggest.

I had no choice. I took the sample yesterday am before the DS Bactrim. Based on the urinalysis from the lab - there are no rbcs but only 25 leukocytes esterase. What I have gathered from using these urinalysis test strips - even higher priced - unless you truly have a higher rbc or wbc count - colour changes at the lower end are subjective to the reader. The sample had no nitrites. Over the last 7 years - since this triology began - nitrites has been the key parameter to guage a symptomatic bladder uti is on the horizon. The microscopy did indicate bacteria though. I also acknowledge I initially captured the urine sample in a reused/washed urine bottle. If I do regular inhouse urinalysis tests - I cant use a new sterile bottle each time. I decanted yesterdays sample into a sterile bottle So I presume, I introduced external contamination. Guess the urine culture will differentiate between a true urine pathogen vs external environmental one. So am hoping the culture will show the latter -env bacteria. I am presuming the Bactrim will hold course. I gave her a DS yesterday, and she was completely fatigued. Her hygiene has improved but still has poor days. So she will have to continue on a low dose preventative to her days end. I have used nitrofuran sporadically the last few months to complement the Bactrim (or give a few days in between rest) so a fungal flare recovers. She didn't have the persistence of breast fungus on nitro or fosfomycin. Although resistance to nitro is low - her uncontrolled diarrhea bouts with nitro are distinctive. She was constipated one day, I gave her one night the 50mg nitro and the next day - she had uncontrolled diarrhea. This has never happened with the Bactrim. As far as the fosfomycin, the resistance to it is so low - labs don't do ecoli sensitivity for it. But I don't count on it - this will be forever with everyone. The urologist gave my mother that option in April to use it every 7 days to get us out the door. I don't want to exhaust that option as fosfomycin is well tolerated. I believe we will continue to use Bactrim and use the nitro in between sporadically. You cautioned against this but its a different dynamic for a 90 year old vs a 20 year one. Thankyou for your insight