Yeast and fungal elements in urine sediment of cats and dogs
Yeast or fungal threads in urine sediment are an uncommon finding. Most often they come from contamination — of an old sample, a voided sample or the container — rather than from the urinary tract itself. A real fungal urinary infection is possible, mainly in animals with a predisposing condition, and it is confirmed by culture rather than by the sediment alone.
What it shows
Under the microscope the lab may see two kinds of fungal elements:
- Yeasts — round to oval colourless bodies, sometimes visibly budding (a small daughter cell growing from the mother cell). The yeasts that cause urinary infection are described as small ovoid cells or pseudohyphae — chains of elongated yeast cells.
- Hyphae — branching threads of moulds.
Environmental mould spores can also land in a sample; their shapes, sizes and colours vary.
Higher than reference — what it may be a sign of
- Contamination — the usual explanation. Yeasts are especially suspect if the sample was voided and/or old. Fungal hyphae in sediment most commonly reflect overgrowth of contaminants, for example in urine that travelled to the lab for several days without refrigeration or preservative.
- Fungal urinary tract infection — uncommon in dogs and cats. It is caused mainly by Candida species, with C. albicans the most frequent; Aspergillus, Cryptococcus and a few other fungi are reported less often. The urinary tract can also be involved as part of a fungal infection elsewhere in the body, and some animals have a bacterial infection at the same time.
- When infection is more likely — Candida normally lives on the genital mucosa, and urinary infection usually develops on a background such as previous antibacterial therapy, suppressed immunity, lower urinary tract disease or surgery, or a urinary catheter. Diabetes mellitus and cancer are reported alongside it.
- A fresh sample taken by needle from the bladder — yeasts or hyphae here deserve more attention, because contamination from outside is unlikely.
Signs of fungal cystitis look like those of bacterial cystitis, and finding yeast is not always linked to disease.
Lower than reference
“Not found” is the usual result, and there is no meaningful “lower”. Sediment findings are not definitive in either direction: the diagnosis of fungal urinary infection is confirmed by growing the fungus on urine culture.
Look at together with
- Bacteria and urine culture — culture confirms a fungus and shows whether bacteria are also present.
- White and red cells in the sediment — signs of inflammation help the vet decide whether yeast reflects infection or contamination.
- Glucose in urine and blood glucose — diabetes is one of the conditions reported with fungal urinary infection.
- Fat droplets and other sediment findings — other lines of the same sediment report.
Units and conversion
This line has no unit and nothing to convert. The result is written in words — “not found”, “few”, “many” — or as a count per microscope field at high magnification, sometimes with a note such as “budding yeast” or “hyphae”. Fungal species are not named from the sediment; that comes from culture.
Reference range
The reference range is on your lab’s form; the expected result is “not found”. How the sample was collected and how fresh it was matter as much as the result itself: yeast in an old voided sample is read very differently from yeast in fresh urine taken from the bladder by needle. Small fat droplets float in a different focal plane and can be mistaken for red cells.
Cats and dogs
The sources describe fungal urinary infection in dogs and cats together and give no separate feline figures. The same background conditions apply to cats — previous antibiotics, suppressed immunity, lower urinary tract disease or surgery, a urinary catheter, diabetes. As in dogs, a single yeast finding in a voided or old sample is most likely contamination.
In a described case, a dog on long-term antibiotic and immunosuppressive therapy had yeasts in fresh urine taken by needle; they formed pseudohyphae and grew Candida albicans on culture. In another dog, a dense mat of fungal hyphae in urine that had been in transit for several days was judged most likely a contaminant, since urinary fungal infection in dogs is uncommon.
Add a lab form — Pet Tracker Space recognises the lines, keeps the form’s units and draws each indicator over time with your lab’s reference band.
Sources
This page explains what a lab value means. It is not a diagnosis and not a substitute for your veterinarian — only they can interpret results for your pet.