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"Could this be an STI or just a yeast infection?"

ZocdocAnswersCould this be an STI or just a yeast infection?


I had unprotected oral sex 8 months ago and protected oral sex 3 months ago. These are the only sexual eaxperiences in that time period. I have been experiencing an itchy feeling on/in the tip of my penis. I went to a walk in clinic and the doctor had me provide a urine sample. The sample came back negative for white blood cells and negative for nitrates. The doctor looked at my urethra under black light and he told me that yeast glows under that light and that it appeared to him to be indicative of a yeast infection. He prescribed a regimen of Fluconazole. He said it was unlikely to be an STI given the urine test. He told me if the symptoms did not clear after that he would test for STI. I am now worried that he even mentioned an STI possibility. With the negative urine test he told me about, is it still possible for me to have an STI? If so, what tests should I ask for?


Most of the time, men who have common sexually transmitted infections like gonorrhea or chlamydia will have abnormal findings on their urinary samples, such as positive white blood cells. Therefore the fact that you had a normal urine sample is reassuring, but I don't think it completely rules out the possibility of a sexually transmitted infection. It is also true that some fungal infections will glow under a black light. However, the most common fungal species that would cause an infection at the tip of the penis are not among the species that would tend to glow. Additionally, fungal infections of the penis are relatively uncommon in otherwise healthy men, although they do occur in those with immune problems such as HIV or chronic medical conditions like diabetes. Taken altogether, I think you intuition to want more definitive testing for a sexually transmitted infection is correct. There are simple tests for both gonorrhea or chlamydia that can be done from either a penile swab or a urine specimen. If you go to see your primary care doctor, I am certain that they would be happy to run these tests for you, especially if your symptoms do not go away with the fluconazole.

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