My fluid buildup in my legs was caused by Cellulitis.  Is that the name of what is causing yours?  If so, it's very dangerous and can spread rapidly if not treated with antibiotics.  Just draining the fluid isn't sufficient to cure it.    Ultrasound testing won't reveal it, they need to biopsy the skin to find out what type of bacteria is responsible for the infection.  Before the results come back on that though (takes a couple of days to culture the samples) it should be treated immediately with a broad-spectrum antibiotic to prevent or at least slow further infection.   You need IV antibiotics for this, not pills.  Hospitalization is necessary.

This disease is life threatening if not treated quickly.  Hopefully it is not what you have, but if it is, you need to be in the hospital and admitted yesterday.

RE