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                                                                 EXHIBIT 10.51.2

                              AMENDMENT NUMBER 1 TO
                       LIMITED LIABILITY COMPANY AGREEMENT

         THIS AMENDMENT NUMBER 1 TO LIMITED LIABILITY COMPANY AGREEMENT (this
"Amendment") is made and entered into this 1st day of July 2002, by and between
MAUMEE DIALYSIS SERVICES, LLC, a Delaware limited liability company (the
"Company"), RCG INDIANA, LLC, a Delaware limited liability company (the "RCG"),
and INDIANA DIALYSIS MANAGEMENT, P.C., an Indiana professional corporation (the
"IDM").

                                   WITNESSETH:
                                   ----------

         WHEREAS, RCG and IDM are parties to Limited Liability Company
Agreement, effective as of December 1, 2001 (the "Agreement"), under which RCG
and IDM formed the Company and which governs the operations of the Company; and

         WHEREAS, the parties to this Amendment now desire to make certain
modifications and amendments to the Agreement as provided herein; and

         WHEREAS, capitalized terms that are used but not defined in this
Amendment that are defined in the Agreement shall have the meanings set forth in
the Agreement;

         NOW, THEREFORE, in consideration of the mutual promises, covenants and
undertakings set forth in this Amendment and in the Agreement, and other good
and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties to this Amendment hereby agree as follows:

         1. Restrictions on Authority of Managers. The parties agree that
Section 3.1.7 of the Agreement is hereby amended by deleting such section in its
entirety and inserting in lieu thereof, the following:

                  3.1.7 Restrictions on Authority of Managers.

                  (a) Without the consent of the Members holding Units
         representing 75% of the outstanding Membership Interests in the Company
         (or Managers representing Members holding such an amount of Membership
         Interests), the Managers have no authority to:

                      (i) do any act in contravention of this Agreement;

                      (ii) do any act which would make it impossible to carry on
         the ordinary business of the Company, except as otherwise provided in
         this Agreement;

                      (iii) possess Property, or assign rights in specific
         Property, for other than a Company purpose;

                      (iv) knowingly perform any act that would subject any
         Member to liability for the obligations of the Company in any
         jurisdiction;

                      (v) file a voluntary petition or otherwise initiate
         proceedings (x) to have the Company adjudicated insolvent or, (y)
         seeking an order for relief of the




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         Company as debtor under the United States Bankruptcy Code (11 U.S.C.
         Sections 101 et seq.); file any petition seeking any composition,
         reorganization, readjustment, liquidation, dissolution or similar
         relief under the present or any future federal bankruptcy laws or any
         other present or future applicable federal, state or other statute or
         law relative to bankruptcy, insolvency, or other relief for debtors
         with respect to the Company; or seek the appointment of any trustee,
         receiver, conservator, assignee, sequestrator, custodian, liquidator
         (or other similar official) of the Company or of all or any substantial
         part of the Property, or make any general assignment for the benefit of
         creditors of the Company, or admit in writing the inability of the
         Company to pay its debts generally as they become due, or declare or
         effect a moratorium on the Company's debt or take any action in
         furtherance of any proscribed action;

                      (vi) require additional Capital Contributions, except as
         specifically contemplated by Section 2.3 of this Agreement;

                      (vii) sell all or substantially all of the Property;

                      (viii) amend this Agreement or the Certificate, if such
         amendment would materially and adversely affect the rights, preferences
         or privileges of the interests of an Initial Member, including an
         amendment, the effect of which would be to cause the Company to be
         taxable as a corporation or to be treated as an association taxable as
         a corporation for federal income tax purposes;

                      (ix) dissolve or terminate the Company;

                      (x) merge the Company into another entity, if the Company
         is not the surviving entity, or if the holders of Units immediately
         prior to the merger hold less than fifty percent of the equity
         interests in the surviving entity immediately after the merger;

                      (xi) amend the Management Agreement;

                      (xii) cause a fundamental change in the nature of the
         Company's business, unless such change is required by applicable law;

                      (xiii) do any other matters expressly set forth in this
         Agreement as requiring the consent, vote or approval of all of the
         Initial Members;

                      (xiv) approve loans by Members to the Company;

                      (xv) approve the borrowing of funds in excess of
         $200,000.00 on the Company's behalf and approve the pledging of assets
         of the Company as security for indebtedness;

                      (xvi) create any new class of membership or other interest
         in the Company;

                     (xvii) admit a Member to the Company; or

                     (xviii) take any other action that is outside the ordinary
         course of the Company's business.



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                           (b) Without the consent of Managers representing
         Members holding Units representing 75% of the outstanding Membership
         Interests in the Company, the Managers have no authority to approve the
         annual operating or capital budget for the Company or any deviation of
         more than $50,000 from the amount shown in an approved budget for any
         item of expense that is within the reasonable control of the Company.
         On or before November 30 of each year RCG will prepare a proposed
         operating and capital budget for the following year, and the Managers
         will promptly review, comment on and, if acceptable, approve such
         budget. The Managers will negotiate in good faith to agree on a budget
         for the coming year. If the Managers, following such good faith
         negotiations, do not agree on a budget, then either party may submit
         the matter to dispute resolution as contemplated by Section 7.2.12. If
         the Managers do not approve a budget before the beginning of a year,
         then the Company shall operate under the approved budget for the prior
         year until the Managers approve a budget for such year.

         2. No Further Amendment. Except as expressly modified and amended by
this Amendment, the parties agree that the Agreement shall continue in full
force and effect as provided therein, and the parties reaffirm all of its
provisions.

         3. Miscellaneous. The section and other headings used in this Amendment
are for convenience of reference only and shall not affect the interpretation of
this Agreement in any way. This Amendment may be executed in multiple
counterparts, each of which shall be deemed an original for all purposes and all
of which shall be deemed, collectively, one agreement.

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         IN WITNESS WHEREOF, this Amendment is executed effective as of the date
first set forth above.

                                       The Company:
                                       -----------

                                       MAUMEE DIALYSIS SERVICES, LLC



                                       By:     /s/ R. Dirk Allison
                                          --------------------------------------
                                       Title:  Vice President of Managing Member
                                             -----------------------------------


                                       RCG:
                                       ---

                                       RCG INDIANA, LLC



                                       By:     /s/ R. Dirk Allison
                                          --------------------------------------
                                       Title:  Vice President of Managing Member
                                             -----------------------------------

                                       IDM:
                                       ---

                                       INDIANA DIALYSIS MANAGEMENT, P.C.



                                       By:      /s/ Stephen D. McMurray
                                          --------------------------------------
                                       Title: President
                                             -----------------------------------









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