FOURTH AMENDMENT TO LEASE
                           -------------------------

    THIS FOURTH AMENDMENT TO LEASE is made this 30th day of May, 1996, between 
TERRAMICS/SOUTHPOINT ASSOCIATES II LIMITED PARTNERSHIP (the "Landlord") and 
RENAL TREATMENT CENTERS, INC. (the "Tenant").

                                  BACKGROUND
                                  ----------

    A.  Landlord and Tenant entered into a lease dated November 8, 1991, as 
amended by a First Amendment to Lease dated January 18, 1993, a Second Amendment
to Lease dated September 30, 1993 and a Third Amendment to Lease dated March 2, 
1995 (the "Existing Lease"), covering office space consisting of approximately 
21,025 rentable square feet (the "Existing Space") on the third floor of the 
building (the "Building") known as Southpoint TWO located at 1180 West 
Swedesford Road in the Southpoint Office Complex, Berwyn, Pennsylvania.

    B.  Landlord and Tenant desire to amend the Existing Lease, under the terms 
and conditions set forth below, to expand the premises covered under the 
Existing Lease to include approximately 20,511 rentable square feet of 
additional space (the "Additional Space") on the second floor of the Building.  
The Additional Space consists of 16,153 rentable square feet (the "First 
Additional Space") which shall be leased to Tenant on June 8, 1996 and 4,358 
rentable square feet (the "Second Additional Space") which shall be leased to 
Tenant on October 1, 1996.  The First Additional Space and the Second Additional
Space are depicted on Exhibit "A" attached to this Amendment.

    C.  The CIT Group/Equipment Financing, Inc. ("CIT") currently leases the 
Additional Space from Landlord.  Landlord and CIT intend to terminate CIT's 
lease for the Additional Space pursuant to a Lease Termination Agreement (the 
"CIT Agreement").

    NOW, THEREFORE, the parties hereto, for good and valuable consideration and 
intending to be legally bound, agree as follows:

    1.  Premises.  Landlord hereby leases to Tenant, and Tenant leases from 
        --------
Landlord, the Additional Space, under the same terms and conditions as are set 
forth in the Existing Lease except as


 
amended by the provisions set forth in this Amendment.  All capitalized terms 
not otherwise defined herein shall have the same meanings ascribed to them in 
the Existing Lease.  The Existing Lease as hereby amended shall be referred to 
herein as the "Lease".

    2.  AS-IS Condition.  Landlord shall deliver and Tenant shall accept the 
        ---------------
Additional Space in its existing "As Is" condition.  Any work requested by 
Tenant shall be performed only if Landlord and Tenant first reach written 
agreement on any charges to Tenant therefor.

    3.  Term.  The term of the Lease with respect to the First Additional Space 
        ----
shall commence on June 8, 1996 and the term of the Lease with respect to the 
Second Additional Space shall commence on October 1, 1996.  Notwithstanding the 
foregoing, if, for any reason, Landlord is unable to deliver possession of the 
Additional Space on the dates described above, Landlord shall not be liable for 
any damage caused thereby, nor shall the Lease be void or voidable, but, rather,
the term of the Lease with respect to the applicable Additional Space shall 
commence upon the date that possession of the applicable Additional Space is 
made available to Tenant.  Unless sooner terminated in accordance with the terms
of the Lease, the term of the Lease with respect to the Additional Space shall 
be coterminous with the term of the Lease with respect to the Existing Space.

    4.  Minimum Annual Rent.  Tenant shall pay a minimum annual rent for the 
Additional Space (until September 30, 1996, for the First Additional Space only)
as follows:

        (a)  for and during the period commencing June 8, 1996 through September
30, 1996, the minimum annual rent for the First Additional Space shall be Ten 
Dollars ($10.00) per rentable square foot or One Hundred Sixty One Thousand Five
Hundred Thirty Dollars ($161,530.00) per annum, payable in equal monthly 
installments of Thirteen Thousand Four Hundred Sixty and 83/100 Dollars 
($13,460.83);

 
          (b)  for and during the period commencing October 1, 1996 through
     February 28, 1998, the minimum annual rent shall be Ten Dollars ($10.00)
     per rentable square foot or Two Hundred Five Thousand One Hundred Ten
     Dollars ($205,110.00), payable in equal monthly installments of Seventeen
     Thousand Ninety-Two and 50/100 Dollars ($17,092.50); and

          (c)  for and during the period commencing March 1, 1998 through
     December 31, 1998, the minimum annual rent shall be Twenty-One and 25/100
     Dollars ($21.25) per rentable square foot or Four Hundred Thirty Five
     Thousand Eight Hundred Fifty-Eight and 75/100 Dollars ($435,858.75) payable
     in equal monthly installments of Thirty Six Thousand Three Hundred Twenty-
     One and 56/100 Dollars ($36,321.56).

          (d)  for and during the balance of the term of the Lease, the minimum
     annual rent shall be Twenty-One Dollars ($21.00) per rentable square foot
     or Four Hundred Thirty Thousand Seven Hundred Thirty-One dollars
     ($430,731.00), payable in equal monthly installments of Thirty-Five
     Thousand Eight Hundred Ninety-Four and 25/100 Dollars ($35,894.25).

Such minimum annual rent shall be paid by Tenant in the same manner as set forth
in the Existing Lease.

     5.   Proportionate Share. As of June 8, 1996, Tenant's Proportionate Share 
          -------------------
shall be increased to Sixty-One and 55/100 percent (61.55%). As of October 1, 
1996, Tenant's Proportionate Share shall be increased to Sixty-Eight and 77/100 
percent (68.77%).

     6.   Definition of Premises. As of June 8, 1996 with respect to the First 
          ----------------------
Additional Space and as of October 1, 1996 with respect to the Second Additional
Space, the term "Premises" as used in the Lease shall be deemed to include the 
Additional Space.

     7.   Broker. Tenant represents and warrants that it has not dealt with any 
          ------
broker or agent in the negotiation for this

                                      -3-


 
Amendment, and agrees to indemnify and hold Landlord harmless from any and all 
costs or liability for compensation claimed by any such broker or agent employed
by Tenant or claiming to have been engaged by Tenant in connection with this 
Amendment.

     8.  Partial Termination Option.  Tenant shall have the right to terminate 
         --------------------------
this Lease with respect to approximately 5,000 rentable square feet of the 
Additional Space (the "Termination Space"), effective March 1, 1998 (the "Early 
Termination Date"), but not at any other time, under the following terms and 
conditions:

         (a)  Tenant shall give Landlord written notice of its election to 
     exercise this option on or before June 1, 1997;

         (b)  Tenant shall pay all installments of minimum annual rent and
     additional rent with respect to the Termination Space accruing up to the
     Early Termination Date;

         (c)  Tenant shall pay all costs associated with segregating the
     Termination Space from the remainder of the Premises and all other costs in
     order for the second floor of the Building to be used as a multi-tenant
     floor.

         (d)  The exact location of the Termination Space shall be reasonably 
     determined by Landlord after consultation with Tenant.

         (e)  Tenant shall not, at the time it exercises its partial termination
     option, be in default under this Lease beyond any applicable period of
     grace.

If Tenant exercises its option to terminate the Lease with respect to the 
Termination Space in accordance with the provisions hereof, the Lease with 
respect to the Termination Space shall be terminated on the Early Termination 
Date without further liability of Tenant hereunder, except for such liability 
that has accrued on or prior to the Early Termination Date and such liability 
that survives termination of the Lease.  After notice has been given to Landlord
of Tenant's election to terminate this Lease with respect to the Termination 
Space, the Termination Space may be shown by Landlord from time to time, at

                                      -4-

 
any time during business hours or any other reasonable time upon reasonable 
prior notice, to prospective tenants.

     9.   Concessions.  Except as provided for herein, Tenant shall not be 
          -----------
entitled to any improvement allowances or any other leasing concessions in 
connection with this Amendment.

     10.  Contingency.  This Amendment is contingent upon CIT and Landlord fully
          -----------
executing the CIT Agreement.  In the event that Landlord and CIT do not fully 
execute the CIT Agreement, the Existing Lease shall remain in full force and 
effect without modification by reason of this Amendment.

     11.  Binding Agreement.  Except as expressly modified by this Amendment, 
          -----------------
the terms and conditions of the Lease shall remain in full force and effect, 
without change.  This Amendment shall be binding upon, and shall inure to the 
benefit of, the parties hereto and their respective successors and assigns.

     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be 
executed by their duly authorized representatives.

                                       TENANT:

                                       RENAL TREATMENT CENTERS, INC., a
                                       Delaware corporation

Date Signed: 5/30/96                   By: /s/ [SIGNATURE APPEARS HERE]
            -------------------           -------------------------------------
                                       Attest: /s/ [SIGNATURE APPEARS HERE]
                                              ---------------------------------
                                                             (corporate seal)

                                       LANDLORD:

                                       TERRAMICS/SOUTHPOINT ASSOCIATES II
                                       LIMITED PARTNERSHIP, a Pennsylvania
                                       limited partnership

Date Signed: 5/30/96                   By: /s/ [SIGNATURE APPEARS HERE]
            -------------------           -------------------------------------
                                          (Authorized Representative)



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SCJTHPOINT                                                     DEMISED AREA PLAN
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Building Two                                                        SECOND FLOOR





                   [PHOTO OF ADDITIONAL SPACE APPEARS HERE]




                                                                    EXHIBIT "A"