Given that leptospirosis is treated with doxycycline, you would have thought that they would have at least done a resistance study on the culture. Even if you don’t know it’s leptospirosis, you can know it’s susceptible to tetracyclines and treat it.
I don't know what kind of resistance study you would order if you don't have an isolate growing. I don't know how you could have a culture growing but not know the causative organism is a Leptospira spp. .