Ah,......he BILLED for $336. First of all, that seems a little excessive, but I won't comment on his billing practices since I don't know what procedures he performed or billed.
He probably billed for a home visit and also billed for nail care AND removal of the infected nail or drainage of the infection.
Unless your mother/grandmother actually paid him up front, he probably billed the insurance company for that amount, and he'll be lucky if he receives 1/2 of that amount.
You can BILL any amount you'd like, but that doesn't mean insurance companies will pay that amount. Often, when you bill a visit in conjunction with other services, one of those services can be either tossed out or reduced in it's fee. Additionally, when you have a contract with an insurance company, the fee you charge and the fee you RECEIVE often differ greatly.
If I received all the fees I BILLED, I would have retired about 10 years ago, and I'm relatively young.
So for all you young guys, PLEASE don't ever be impressed by the amount that any doctor "BILLS". This is for several reasons. Number one is that you rarely if ever receive the amount you bill. The second reason is that unfortunately, not all doctors are ethical, and some can bill very aggressively or overbill. So don't "count the money" yet.
There was a local DPM several years ago that had ONLY a housecall practice. No office, no secretary, no overhead, etc. He only made housecalls. So realistically, you really can't see that many patients a day, because you've got to drive all over the place. And obviously, you can't perform surgery, so all you're doing all day is routine care.
Well, this guy RECEIVED (not billed) over $960,000 as an average over a 4 year period from Medicare (my friend was the Medicare reviewer). When he was finally "caught", it was because everytime he did a housecalll, he didn't simply bill for "nail care", etc.
He billed for cutting of mycotic nails, several ingrown toenails, draining an infection, trimming calluses, and multiple procedures PER patient. I believe his average bill PER patient PER visit was over $650. However, when Medicare called these patients, they said "I just called the doctor so he could cut my nails".
When Medicare did a review, they compared this doctor to the "average" doctor in his geographic area performing the same service during the same period. The average DPM making housecalls was billing an average of $84 per patient per visit and was making 2 housecalls per month vs. a this guy billing a gazillion.
So, don't start counting the money based on ONE doctor's bill on ONE visit. There's always more to the story. And assuming your grandmother's visit was 100% legitimate, unless he was paid cash, it's doubtful that the insurance company will pay close to the amount billed.