If you eval the following macro and view its doc with 'C-h f', you will
notice that ewoc is not recognised as an argument,i.e. it remains in
lower case and EWOC in the doc-string is not italic.

(defmacro* %with-ewoc-node ((var ewoc) &body body)
  "Bind VAR to the EWOC node at point. When VAR is non-nil, execute BODY."
  (declare (indent 1) (debug t))
  `(let ((,var (ewoc-locate ,ewoc)))
     (when ,var ,@body)))

See this screenshot: