I called back today and it was disconnected.

Kaiser Permanente - Rock Creek Neurology Department

I just received a call from this number on my cellphone, no message left and when I called back number was disconnected.  I do not owe any outstanding bills, so not sure it is a bill collector?? wouldn't they leave a message ?

I received a call from this number but when I called it back the number was disconnected

I recieved a call from this number, It appears to be an internal line for a Kaiser Permanente facility