Shortcode Comma Separated Category – Can I AND / OR?

I am making a dynamically generated listing output based on region & specialty.

The php that generates the shortcode will look something like this:

$region = $parameters['region'];
$specialty = $parameters['specialty'];
$categories = join(",",$parameters);
$shortcode = "[abcf-staff-grid-a id=\"220\" category=\"$categories\"]";

…where $categories will become something like “arizona,therapist”.

When I pass the shortcode with a comma separated categories list, the page will output everything for arizona. I guess this means the categories is an OR list. Is there a way to filter on “arizona AND therapist”, rather than “arizona OR therapist” ?

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