Why would a doctor not treat Candida parapsilosis in a M91?

September 26, 2024 7:08 AM

Likely it’s to do with recent catheterization (earlier this year) and/or frequent antibiotics for UTIs. This turned up in a urine culture and they said it’s not worth treating. But I see papers saying it could be fatal, cause sepsis and cardiological complications etc?

I gave him 150 mg fluconazole OTC from the pharmacy but seems it is persistent?

posted by cotton dress sock to Health & Fitness (6 answers total)

You may have heard of the microbiome, or the idea that there are microorganisms that colonize the human body without causing disease (and that, in some cases, actually promote health, the so-called "good bacteria"). Urine cultures often turn up organisms that are not "pathogenic," that is, disease causing, but are merely "colonizing" the part of the body the culture was collected from.

Candida species are a common colonizer of the urinary tract, meaning that the organism is there living in the body but not causing disease. In that situation, it is generally neither possible nor helpful to patients to attempt to eradicate these organisms. More often than not they will simply come back, or else another organism will take their place in that ecosystem, and in the process the patient is exposed to potential side effects from antibiotic or antifungal treatment. When there is no evidence that the Candida is currently causing disease and no factors that make the patient especially susceptible to developing disease (e.g., severe immunosuppression from chemotherapy), it is safer to not treat.
posted by telegraph at 8:16 AM on September 26

Thank you, telegraph - I sincerely appreciate your response.

My worry is that at least one paper identified a number of clinical implications of this specific species (vs albicans) - endocarditis (person does have an enlarged heart) and valve problems (likewise), meningitis (person has been experiencing delirium and headache), Peritonitis (no idea if this applies but various urinary and GI symptoms are present), and UTI (this for sure! Smelly , cloudy pee, dipstick showed white blood cells , blood,, - also couldn’t void. Urine Cultures negative for bacteria but has been on like 3 antibiotics in the past month). Thankfully blood cultures are clean and I’m guessing that’s why they’re not worried?

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2570155/

https://www.nature.com/articles/s41579-023-00961-8
posted by cotton dress sock at 10:28 AM on September 26

Maybe docs fear too many antifungals may cause more problems than cure them in a person of this advanced age with his health situation, for something unlikely to cause harm in the first place?
posted by tristeza at 1:29 PM on September 26

Antibiotics can cause delirium in elderly patients, so that may be part of the calculus.
posted by brook horse at 5:27 PM on September 26

I am not a doctor. I think you are confusing a cardiac catheter with a urinary catheter. Cardiac catheterization could introduce candida and cause endocarditis.
posted by pintapicasso at 7:25 PM on September 26

I'm not a doctor, and this isn't medical advice. I'd encourage you to follow up with the medical team managing this person's medical care if you still have concerns.

Candida parapsilosis is part of the human microbiome, and the providers managing this person's care may suspect this finding was due to a contaminated sample. Or it may have been found in such a small quantity that the providers are doing a risk/benefit analysis and think that treating with antifungals might cause more harm than good. From my (limited) understanding of critically ill ICU patients, there can be a considerable concern that finding Candida parapsilosis in this patient population's urine sample can indicate that they have candidemia AKA fungus in the blood. You report that blood cultures were run, and they showed no sign of infection, which is great news! This is likely why providers do not suspect this patient's other symptoms are caused by a disseminated candida parapsilosis infection. UTIs can cause delirium (confusion, a change in mentation) in elderly people and it sounds like this person is still having urinary signs so I would follow up with their providers about your concerns. I hope they start feeling better soon. Good luck to you both.
posted by malum geminae at 2:34 PM on September 28