EXHIBIT 5.1

ALSTON & BIRD LLP
One Atlantic Center
1201 West Peachtree Street
Atlanta, Georgia 30309-3424

404-881-7000
Fax: 404-881-4777
www.alston.com

December 21, 2004

Renal Care Group, Inc. and the
Subsidiary Guarantors listed on Annex A
2525 West End Avenue, Suite 600
Nashville, Tennessee 37203

Re: Registration Statement on Form S-3

Ladies and Gentlemen:

We have acted as counsel to Renal Care Group, Inc., a Delaware
corporation (the "Company"), and the subsidiaries of the Company listed on Annex
A hereto (the "Subsidiary Guarantors" and together with the Company, the "RCG
Entities"), in connection with the Company's registration statement on Form S-3
(the "Registration Statement") filed with the Securities and Exchange Commission
(the "Commission") under the Securities Act of 1933, as amended (the "Securities
Act") on September 24, 2004, relating to the registration of $160,000,000
aggregate principal amount of the Company's 9% Senior Subordinated Notes due
2011 (the "Notes") and related guarantees by the Subsidiary Guarantors of the
Notes (the "Guarantees" and together with the Notes, the "Securities") pursuant
to (i) the Indenture, dated as of October 22, 2003 (including any supplemental
indenture, the "Indenture") by and among the Company, as successor to National
Nephrology Associates, Inc. ("NNA"), the Subsidiary Guarantors named therein and
Wells Fargo Bank, N.A., as successor in interest to Wells Fargo Bank Minnesota,
N.A., as trustee (the "Trustee"), (ii) the First Supplemental Indenture, dated
as of April 2, 2004, by and among the Company, the Subsidiary Guarantors named
therein and the Trustee, (iii) the Second Supplemental Indenture, dated as of
April 30, 2004 by and among the Company, the Subsidiary Guarantors named therein
and the Trustee, and (iv) the Registration Rights Agreement dated October 22,
2003 by and among the Company, as successor to NNA, the Subsidiary Guarantors
named therein and Banc of America Securities LLC, J.P. Morgan Securities Inc.,
RBC Dominion Securities Corporation, and Harris Nesbitt Corp. (the "Registration
Rights Agreement"). This opinion is furnished at your request to enable you to
fulfill the requirements of Item 601(b)(5) of Regulation S-K, 17 C.F.R. Section
229.601(b)(5) in connection with the Registration Statement.

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Bank of America Plaza 90 Park Avenue 3201 Beechleaf Court, Suite 600 601 Pennsylvania Avenue, N.W.
101 South Tryon Street, Suite 4000 New York, NY 10016 Raleigh, NC 27604-1062 North Building, 10th Floor
Charlotte, NC 28280-4000 212-210-9400 919-862-2200 Washington, DC 20004-2601
704-444-1000 Fax: 212-210-9444 Fax: 919-862-2260 202-756-3300
Fax: 704-444-1111 Fax: 202-756-3333
</Table>

Renal Care Group, Inc. and Subsidiary Guarantors
December 21, 2004
Page 2

The Guarantees are set forth in Article Eleven of the Indenture and a
notation of the Guarantees is endorsed on each Note or otherwise deemed to be
delivered therewith under the terms of the Indenture. The Indenture is subject
to and governed by the Trust Indenture Act of 1939, as amended (the "TIA").

We have examined the forms of the Securities, the Indenture, the
Registration Rights Agreement, the Registration Statement, including the amended
Statement of Eligibility under the TIA of the Trustee filed as an exhibit
thereto, and such documents, records, certificates and other instruments as we
have deemed necessary or advisable for the purposes of rendering the opinions
hereafter set forth. We also have made such further legal and factual
examinations and investigations as we deemed necessary for purposes of
expressing the opinions set forth herein.

As to certain factual matters relevant to this opinion letter, we have
relied conclusively upon originals or copies, certified or otherwise identified
to our satisfaction, of such records, agreements, documents and instruments,
including certificates or comparable documents of officers of the RCG Entities
and certificates of public officials, as we have deemed appropriate as a basis
for the opinions hereinafter set forth. Except to the extent expressly set forth
herein, we have made no independent investigations with regard to matters of
fact, and, accordingly, we do not express any opinion as to matters of fact that
might have been disclosed by independent verification.

We have assumed, without any independent verification, (i) the
genuineness of all signatures, (ii) the legal capacity of all natural persons,
(iii) the authenticity of all documents submitted to us as originals, (iv) the
conformity to the original documents of all documents submitted to us as
conformed, facsimile, photostatic or electronic copies, (v) that the forms of
the Securities conform to those included in the Indenture, (vi) based upon
recent certificates of the Secretaries of State or similar government officials
of the State of Delaware or other jurisdictions indicated on Annex A (or recent
informal confirmations of Corporation Service Company or its affiliates), that
each of the RCG Entities is a corporation, limited partnership or limited
liability company, validly existing under the laws of its jurisdiction of
incorporation or formation, (vii) that all parties other than the Company to the
documents examined by us have the requisite corporate, partnership or limited
liability company power and authority under the laws of their respective
jurisdictions of incorporation or formation to execute, deliver and perform
their obligations under such documents and under the other documents required or
permitted to be delivered and performed thereunder, and (viii) the due
authorization, execution and delivery of the Indenture and the Securities by the
Subsidiary Guarantors other than corporations organized under the laws of the
States of Delaware and Georgia, as indicated on Annex A, under the laws of their
respective jurisdictions of incorporation or formation. We have also assumed
that the Indenture has been duly authorized, executed and delivered by the
Trustee, and constitutes the valid and binding obligation of the Trustee,
enforceable against the Trustee in accordance with its terms, and that the
Trustee is, with respect to acting as a trustee under the Indenture, in
compliance with all applicable laws and regulations.

Renal Care Group, Inc. and Subsidiary Guarantors
December 21, 2004
Page 3

This opinion is limited in all respect to the federal laws of the
United States of America, the laws of the State of New York, the laws of the
State of Georgia, and the Delaware General Corporation Law (together with
applicable provisions of the Constitution of the State of Delaware and reported
judicial interpretations thereof). We express no opinion herein as to any other
laws, rules or regulations.

Based upon and subject to the foregoing, and subject to the other
assumptions, qualifications, limitations and exceptions set forth herein, we are
of the opinion that:

1. The Notes, when duly authenticated by the Trustee and issued and
delivered in accordance with the provisions of the Indenture, constitute valid
and legally binding obligations of the Company, enforceable against the Company
in accordance with their terms, except as the enforcement thereof may be limited
by bankruptcy, insolvency (including, without limitation, all laws relating to
fraudulent transfers), reorganization, moratorium or other similar laws
affecting creditors' rights generally, and except as the enforcement thereof is
subject to general principles of equity (regardless of whether enforcement is
considered in a proceeding in equity or at law).

2. The Guarantees constitute valid and legally binding obligations of
the Subsidiary Guarantors, enforceable against the Subsidiary Guarantors in
accordance with their terms, except as the enforcement thereof may be limited by
bankruptcy, insolvency (including, without limitation, all laws relating to
fraudulent transfers), reorganization, moratorium or other similar laws
affecting creditors' rights generally, and except as the enforcement thereof is
subject to general principles of equity (regardless of whether enforcement is
considered in a proceeding in equity or at law).

This opinion letter is provided for use solely in connection with the
transactions contemplated by the Registration Statement and may not be used,
circulated, quoted or otherwise relied upon for any other purpose without our
express written consent. Our opinions herein are limited to those matters set
forth in Opinion Paragraphs 1 and 2 above, and no opinion may be implied or
inferred beyond the opinions expressly stated. This opinion letter is effective
as of the date hereof and we hereby expressly disclaim any obligation to
supplement the opinions expressed herein for any changes which may occur
hereafter with respect to any matters of fact or law addressed herein.

Renal Care Group, Inc. and Subsidiary Guarantors
December 21, 2004
Page 4

We consent to the filing of this opinion letter as an exhibit to the
Registration Statement and to the use of our firm's name under the heading
"Legal Matters" in the Prospectus constituting a part thereof. In giving such
consent, we do not thereby admit that we are within the category of persons
whose consent is required under Section 7 of the Securities Act or the rules and
regulations of the Commission thereunder.

Very truly yours,

ALSTON & BIRD LLP

By /s/ Paul M. Cushing
---------------------------------
Paul M. Cushing
A Partner

ANNEX A

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<Caption>
ENTITY STATE OF INCORPORATION OR FORMATION
- ------ -----------------------------------

NNA of Oklahoma, Inc. Nevada

NNA of Georgia, Inc. Delaware

NNA of Alabama, Inc. Alabama

NNA Management Company of Kentucky, Inc. Kentucky

National Nephrology Associates Management Company
of Texas, Inc. Texas

NNA of Nevada, Inc. Nevada

National Nephrology Associates Credit Corporation Tennessee

NNA of Toledo, Inc. Ohio

NNA of Rhode Island, Inc. Rhode Island

NNA Properties of New Jersey, Inc. New Jersey

NNA Management Company of Louisiana, Inc. Louisiana

Renex Corp. Florida

Renex Management Services, Inc. Florida

Dialysis Services of Atlanta, Inc. Georgia

Renex Dialysis Clinic of Penn Hills, Inc. Pennsylvania

Renex Dialysis Clinic of Shaler, Inc. Pennsylvania

Renex Dialysis Clinic of Doylestown, Inc. Pennsylvania

Renex Dialysis Clinic of Amesbury, Inc. Massachusetts

Renex Dialysis Clinic of North Andover, Inc. Massachusetts

Renex Dialysis Clinic of South Georgia, Inc. Georgia

Renex Dialysis Clinic of Creve Couer, Inc. Missouri

Renex Dialysis Clinic of St. Louis, Inc. Missouri
</Table>

<Table>
<Caption>
ENTITY STATE OF INCORPORATION OR FORMATION
- ------ -----------------------------------

Renex Dialysis Clinic of Bridgeton, Inc. Missouri

Renex Dialysis Clinic of Union, Inc. Missouri

Renex Dialysis Homecare of Greater St. Louis, Inc. Missouri

Renex Dialysis Clinic of Maplewood, Inc. Missouri

Renex Dialysis Clinic of University City, Inc. Missouri

Renex Dialysis Facilities, Inc. Mississippi

Renex Dialysis Clinic of Bloomfield, Inc. New Jersey

Renex Dialysis Clinic of Orange, Inc. New Jersey

Renex Dialysis Clinic of Philadelphia, Inc. Pennsylvania

Renex Dialysis Clinic of Pittsburgh, Inc. Pennsylvania

Renex Dialysis Clinic of Woodbury, Inc. New Jersey

Renex Dialysis Clinic of Tampa, Inc. Florida

Dialysis Associates, LLC Tennessee

Dialysis Associates Medical Supply, LLC Tennessee

NNA-Saint Barnabas, L.L.C. New Jersey

NNA Saint Barnabas - Livingston, L.L.C. New Jersey

NNA of Oklahoma, L.L.C. Oklahoma

NNA of Louisiana, LLC Louisiana

Doylestown Acute Renal Services, L.L.C. Pennsylvania

NNA of Newark, L.L.C. New Jersey

National Nephrology Associates of Texas, L.P. Texas

NNA Properties of Tennessee, Inc. Tennessee

NNA Transportation Services Corporation Tennessee

Renal Care Group East, Inc. Pennsylvania
</Table>

<Table>
<Caption>
ENTITY STATE OF INCORPORATION OR FORMATION
- ------ -----------------------------------

Renal Care Group Michigan, Inc. Delaware

Kentucky Renal Care Group, LLC Delaware

Michigan Home Dialysis Center, Inc. Michigan

Renal Care Group of the Midwest, Inc. Kansas

Four State Regional Dialysis Center, Inc. Missouri

Fort Scott Regional Dialysis Center, Inc. Missouri

Miami Regional Dialysis Center, Inc. Missouri

RCG Mississippi, Inc. Delaware

Renal Care Group of the Southeast, Inc. Florida

Northeast Alabama Kidney Clinic, Inc. Alabama

Renal Care Group Texas, Inc. Texas

Dialysis Management Corporation Texas

RCG PA Merger Corp. Texas

STAT Dialysis Corporation Delaware

Angleton Dialysis, Inc. Texas

Brazoria Kidney Center, Inc. Texas

Fondren Dialysis Clinic, Inc. Texas

Wharton Dialysis, Inc. Texas

Jefferson County Dialysis, Inc. Arkansas

KDCO, Inc. Missouri

Lawton Dialysis Inc. Arkansas

Little Rock Dialysis, Inc. Arkansas

Northwest Dialysis, Inc. Arkansas

RenaLab, Inc. Delaware

RCG Finance, Inc. Delaware
</Table>

iii

<Table>
<Caption>
ENTITY STATE OF INCORPORATION OR FORMATION
- ------ -----------------------------------

RenalPartners, Inc. Delaware

RenalNet, Inc. Delaware

Diabetes Care Group, Inc. Delaware

Renal Care Group Arizona, Inc. Arizona

Renal Care Group Northwest, Inc. Delaware

RenalNet Arizona, Inc. Arizona

RCG University Division, Inc. Tennessee

R.C.G. Supply Company Tennessee

Renal Care Group Alaska, Inc. Alaska

Renal Care Group Southwest Holdings, Inc. Delaware

Dialysis Centers of America - Illinois, Inc. Illinois

SSKG, Inc. Illinois

Renal Care Group Ohio, Inc. Delaware

Physicians Dialysis Company, Inc. Pennsylvania

Dialysis Licensing Corp. Delaware

RCGIH, Inc. Delaware

Renal Care Group Southwest, L.P. Delaware

Arizona Renal Investments, LLC Delaware

RCG Indiana, L.L.C. Delaware

Stuttgart Dialysis, LLC Arkansas

RCG West Health Supply, L.L.C. Arizona

Renal Care Group Texas, LP Delaware

Wound Care Group, Inc. Delaware

Renal Care Group Westlake, LLC Delaware
</Table>