GUARANTOR ACKNOWLEDGMENT AND AGREEMENT

     Each of the undersigned consents and agrees to and acknowledges the
terms of the foregoing Amendment No. 6 to Credit Agreement, dated as of
February 27, 2009. Each of the undersigned specifically acknowledges the
terms of and consent to the waivers set forth therein.  Each of the
undersigned further agrees that the obligations of each of the undersigned
pursuant to the Closing Date Guaranty executed by each of the undersigned
shall remain in full force and effect and be unaffected hereby.

     Each of the undersigned, by signing below, hereby waives and releases
the Lender and its respective directors, officers, employees, attorneys,
affiliates and subsidiaries from any and all claims, offsets, defenses and
counterclaims of which any of the undersigned is aware, such waiver and
release being with full knowledge and understanding of the circumstances and
effect thereof and after having consulted legal counsel with respect thereto.

     EACH OF THE UNDERSIGNED WAIVES ANY RIGHT TO HAVE A JURY PARTICIPATE IN
RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT OR OTHERWISE, AMONG
ANY OF THE UNDERSIGNED, THE BORROWER AND/OR THE LENDER, ARISING OUT OF, IN
CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE RELATIONSHIP ESTABLISHED
AMONG THEM IN CONNECTION WITH THIS AGREEMENT, THE CREDIT AGREEMENT, THE NOTE
OR OTHER RELATED WRITING, INSTRUMENT, DOCUMENT OR AGREEMENT EXECUTED OR
DELIVERED IN CONNECTION HEREWITH OR THE TRANSACTIONS RELATED THERETO.

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     IN WITNESS WHEREOF, each of the undersigned has duly executed and
delivered this Guarantor Acknowledgement and Agreement as of the date first
written above.

                             DCA of Adel, LLC
                             DCA of Aiken, LLC
                             DCA of Barnwell, LLC
                             DCA of Calhoun, LLC
                             DCA of Camp Hill, LLC
                             DCA of Central Valdosta, LLC
                             DCA of Chesapeake, LLC
                             DCA of Columbus, LLC
                             DCA of Edgefield, LLC
                             DCA of Fitzgerald, LLC
                             DCA of Hyattsville, LLC
                             DCA of Lemoyne, Inc.
                             DCA of Manahawkin, Inc.
                             DCA of Mechanicsburg, LLC
                             DCA of North Baltimore, LLC
                             DCA of Norwood, LLC
                             DCA of Rockville, LLC
                             DCA of Royston, LLC
                             DCA of Selinsgrove, LLC
                             DCA of So. Ga., LLC
                             DCA of South Aiken, LLC
                             DCA of Warsaw, LLC
                             DCA of Wellsboro, Inc.
                             Keystone Kidney Care, Inc.
                             York Realty Managers, LLC

                                 /s/ Stephen W. Everett
                             By:--------------------------------------
                                 Name: Stephen W. Everett
                                 Title: President of each of the foregoing
                                          Guarantors