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                                                                    EXHIBIT 3.54

                             CODE OF REGULATIONS OF
                      CONSULTANT PATHOLOGY ASSOCIATES, INC.

                                    ARTICLE I

                                     SHARES

     SECTION 1.1 - SHARE OWNERSHIP. Shares shall be issued only to persons who
are licensed to practice medicine in the State of Ohio or as may be otherwise
permitted by the laws of the State of Ohio. The decision to sell shares of the
corporation shall be made by the shareholders. The terms of ownership and
transferability of shares may be the subject of standard agreements adopted by
the corporation and executed with the shareholders. The execution of such
agreements as may be in common use shall be a condition of the ownership of
shares by an individual.

     SECTION 1.2 - CERTIFICATES. Certificates for shares, certifying the number
of fully paid shares owned, shall be issued to each shareholder in such form as
shall be approved by the Board of Directors. Such certificates shall be signed
by the chairman of the board, president or a vice president and by the secretary
or an assistant secretary or the treasurer or an assistant treasurer. A full
record of each certificate so issued shall be maintained.

     SECTION 1.3 - REGISTRATION OF TRANSFER. Certificates shall be transferable
in person or by written power of attorney, but no transfer shall be entered upon
the record until previous certificate for such shares has been surrendered to
the corporation; provided, however, that the directors shall have authority to
enact such rules as they shall deem expedient from time to time concerning the
issuance or transfer of certificates.

     SECTION 1.4 - LOST, DESTROYED OR STOLEN CERTIFICATES. A new share
certificate or certificates may be issued in place of any certificate
theretofore issued by the corporation which is alleged to have been lost,
destroyed or wrongfully taken upon, (i) the execution and delivery to the
corporation by the person claiming the certificate to have been lost, destroyed
or wrongfully taken of an affidavit of that fact, specifying whether or not, at
the time of such alleged loss, destruction or taking, the certificate was
endorsed, and (ii) the furnishing to the corporation of indemnity and other
assurances satisfactory to the corporation against any and all losses, damages,
costs, expenses or liabilities to which they or any of them may be subjected by
reason of the issue and delivery of such new certificate or certificates or in
respect of the original certificate.

     SECTION 1.5 - REGISTERED SHAREHOLDERS. A person in whose name shares are of
record on the books of the corporation shall conclusively be deemed the
unqualified owner and holder thereof for all purposes and to have capacity to
exercise all rights of ownership. The corporation shall not be bound to
recognize any equitable interest in or claim to such shares on the part of any
other person, whether disclosed upon such certificate or otherwise, nor shall
they be obliged to see to the execution of any trust or obligation.

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                                   ARTICLE II

                                  SHAREHOLDERS

     SECTION 2.1 - ANNUAL MEETING. The annual meeting of the shareholders of the
corporation shall be held at such time and on such date within two (2) months
before or four (4) months after the close of the business year of the
corporation, as may be fixed by the Board of Directors and stated in the notice
of the meeting.

     SECTION 2.2 - SPECIAL MEETINGS. Special meetings of the shareholders shall
be called upon the written request of the chairman of the board (if any), the
president, the directors by action at a meeting, a majority of the directors
acting without a meeting, or of the holders of shares entitling them to exercise
more than twenty-five percent (25%) of the voting power of the corporation
entitled to vote thereat. Calls for such meetings shall specify the purposes
thereof. No business other than that specified in the call shall be considered
at any special meeting.

     SECTION 2.3 - NOTICE OF MEETINGS. Unless waived, written notice of every
annual or special meeting of the shareholders stating the time, location, and
purpose thereof shall be given, as of a record date fixed by the directors, to
each shareholder entitled to vote thereat, or entitled to notice thereof as
provided by law, by mailing such notice to the last known address of each
shareholder as it appears on the records of the corporation, or by personal
delivery, not less than seven (7) nor more than sixty (60) days prior to such
meeting. A shareholder may waive in writing such notice either before or after
the meeting, and notice shall be waived by attendance at the meeting unless lack
of proper notice is alleged prior to or at the commencement of the meeting. Any
written waiver shall be filed with or entered upon the records of the meeting.

     SECTION 2.4 - PLACE OF MEETINGS. Meetings of shareholders shall be held at
the principal office of the corporation unless the Board of Directors determines
that a meeting shall be held at some other place within or out of the State of
Ohio and causes the notice thereof to so state.

     SECTION 2.5 - QUORUM. The holders of shares entitling them to exercise
seventy percent (70%) of the voting power of the corporation entitled to vote at
any meeting, in person or by proxy, shall constitute a quorum for the
transaction of business to be considered at such meeting; provided, however,
that no action required by law or by the Articles of Incorporation (the
"Articles") or these Regulations to be authorized or taken by the holders of a
designated proportion of the shares of any particular class or of each class may
be authorized or taken by a lesser proportion. The holders of a majority of the
voting shares represented at a meeting, whether or not a quorum is present, may
adjourn such meeting from time to time, until a quorum shall be present.

     SECTION 2.6 - RECORD DATE. The Board of Directors may fix a record date
for any lawful purpose, including, without limiting the generality of the
foregoing, the determination of shareholders entitled to (i) receive notice
of or to vote at any meeting, (ii) receive payment of dividend or
distribution, (iii) receive or exercise rights of purchase of or subscription
for,

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or exchange or conversion of, shares or other securities, subject to any
contract right with respect thereto, or (iv) participate in the execution of
written consents, waivers or releases. Said record date shall not be more than
sixty (60) days preceding the date of such meeting, the date fixed for the
payment of any dividend or distribution or the date fixed for the receipt or the
exercise of rights, as the case may be. If a record date shall not be fixed, the
record date for the determination of shareholders who are entitled to notice of,
or who are entitled to vote at, a meeting of shareholders, shall be the close of
business on the date next preceding the day on which notice is given, or the
close of business on the date next preceding the day on which the meeting is
held, as the case may be.

     SECTION 2.7 - VOTING. Except as provided by law or in the Articles, every
shareholder entitled to vote shall be entitled to cast one vote on each proposal
submitted to the meeting for each share held of record by him or her on the
record date for the determination of the shareholders entitled to vote at the
meeting. At any meeting at which a quorum is present, all questions and business
which may come before the meeting shall be determined by the affirmative vote of
the holders of seventy percent (70%) of the voting power of the corporation,
except when a greater proportion is required by law, the Articles, or these
Regulations.

     SECTION 2.8 - PROXIES. A person who is entitled to attend a shareholder
meeting, to vote thereat, or to execute consents, waivers and releases, may be
represented at such meeting or vote thereat, and execute consents, waivers, and
releases, and exercise any of his rights, by proxy or proxies appointed by a
writing signed by such person, as provided by the laws of the State of Ohio,
provided, however, that such a proxy holder shall likewise be a shareholder of
the corporation.

     SECTION 2.9 - ORDER OF BUSINESS.  The order of business at all meetings
of the shareholders shall be as determined by the chairman of the meeting.

     SECTION 2.10 - ACTION WITHOUT A MEETING. Any action which may be authorized
or taken at a meeting of shareholders, may be authorized or taken without a
meeting by writing or writings signed by all of the shareholders who would be
entitled to notice of a meeting of the shareholders held for the purpose of such
action, which writing or writings shall be filed with or entered upon the
records of the corporation.

                                   ARTICLE III

                                    DIRECTORS

     SECTION 3.1 - GENERAL POWERS. The business, power and authority of this
corporation shall be exercised, conducted and controlled by a Board of
Directors, except where the law, the Articles or these Regulations require
action to be authorized or taken by the shareholders.

     SECTION 3.2 - NUMBER. The number of directors shall equal the number of
share holders. Such number may be fixed or changed by resolution approved by the
affirmative of holders of shares of stock of the corporation as provided for in
Section 2.7 or adopted

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by the affirmative vote or approval of and in a writing or writings signed by
all the shareholders who would be entitled to notice of a meeting of the
shareholders held for such purpose.

     SECTION 3.3 - ELECTION. Each shareholder shall be a director. If at any
time the number of directors is to be less than the number of shareholders, then
there shall be held an election of directors. At each meeting of the
shareholders for the election of directors, the nominees receiving the greatest
number of votes shall become the directors. Directors may be elected at any
meeting of the shareholders if the notice therefore states that one of the
purposes of such meeting is the election of directors.

     SECTION 3.4 - TENURE OF OFFICE. Each director shall hold office until the
annual meeting of shareholders next following his or her election and until his
or her successor is elected and qualified, or until his or her earlier
resignation, removal from office, or death. A director not reelected at a
special meeting of shareholders, one of the purposes of which is the election of
a director for such post, shall be deemed to have been removed from office.
Directors shall be subject to removal as provided by law or by other lawful
procedures and nothing herein shall be construed to prevent the removal of any
or all directors in accordance therewith.

     SECTION 3.5 - RESIGNATION. A resignation from the Board of Directors, shall
be deemed to take effect immediately upon its being received by an incumbent
corporate officer other than an officer who is also the resigning director,
unless such other time is specified therein.

     SECTION 3.6 - VACANCY. In the event of any vacancy in the Board of
Directors for any cause, the remaining directors may, by a vote of a majority of
their number, fill any such vacancy for the unexpired term.

     SECTION 3.7 - MEETINGS. A regular meeting of the Board of Directors shall
be held immediately following the adjournment of the annual meeting of the
shareholders or a special meeting of the shareholders at which directors are
elected. The holding of such shareholders' meeting shall constitute notice of
such directors' meeting and such meeting may be held without further notice.
Other regular meetings shall be held at such other times and places as may be
fixed by the directors. Special meetings of the Board of Directors may be held
at any time upon call of the chairman of the board, if any, the president, or
any two (2) directors. Any meeting of directors may be held at any place within
or without the State of Ohio in person and/or through any communications
equipment if all persons participating in the meeting can hear each other.

     SECTION 3.8 - NOTICE OF MEETING. Notice of the time and place of any
regular or special meeting of the Board of Directors (other than the regular
meeting of directors following the adjournment of the annual meeting of the
shareholders or following any special meeting of the shareholders at which
directors are elected) shall be given to each director by personal delivery,
telephone, facsimile, mail, telegram or cablegram at least forty-eight (48)
hours before the meeting, which notice need not specify the purpose of the
meeting. Such however, may be waived in writing by any director either before or
after any such

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meeting, or by attendance at such meeting (including attendance (presence) by
means of participation through any communications equipment as above provided)
without protest prior to the commencement thereof.

     SECTION 3.9 - QUORUM AND VOTING. At any meeting of directors, no fewer than
a majority of directors then in office must be present, in person and/or through
any communications equipment, to constitute a quorum for such meeting, except
that a majority of the remaining directors in office constitutes a quorum for
filling a vacancy in the Board of Directors. At any meeting at which a quorum is
present, all acts, questions and business which may come before the meeting
including, without limitation, the election of officers shall be determined by
seventy percent (70%) of votes cast by the directors present at such meeting,
unless the vote of a greater number is required by the Articles or Regulations.

     SECTION 3.10 - ACTION WITHOUT A MEETING. Any action which may be taken at a
meeting of directors may be taken without a meeting if authorized by a writing
or writings signed by all of the directors, which writing or writings shall be
filed with or entered upon the records of the corporation.

                                   ARTICLE IV

                                    OFFICERS

     SECTION 4.1 - GENERAL PROVISIONS. The Board of Directors shall elect a
President, a vice president, a secretary and a treasurer, and may elect such
other officers and assistant officers as the Board of Directors may from time to
time deem necessary. Until the annual meeting of shareholders in 2001, of the
president and the vice president, one (1) shall be a person who is regularly
providing full-time services for the corporation at Western Reserve Care System,
and the other shall be a person who is regularly providing full-time services at
St. Elizabeth Health Center. The same provision shall apply with regard to the
positions of secretary and of treasurer. Any two (2) or more offices (other than
the president and vice president and the secretary and the treasurer) may be
held by the same person, but no officer shall execute, acknowledge or verify any
instrument in more than one capacity if such instrument is required to be
executed, acknowledged or verified by two (2) or more officers. Certain officers
may receive compensation for their services in such amounts as the directors may
decide from time to time.

     SECTION 4.2 - POWERS AND DUTIES. All officers, as between themselves and
the corporation, shall respectively have such authority and perform such duties
as are customarily incident to their respective offices, and as may be specified
from time to time by the Board of Directors, regardless of whether such
authority and duties are customarily incident to such office. In the absence of
any officer of the corporation, or for any other reason the Board of Directors
may deem sufficient, the Board of Directors may delegate for the time being, the
powers or duties of such officer, or any of them, to any other officer or to any
director.

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     SECTION 4.3 - TENURE OF OFFICE. Each officer of the corporation shall hold
office for a term of one (1) year until his or her successor has been elected or
until his or her earlier resignation, removal from office or death. The election
or appointment of an officer for a given [ILLEGIBLE], or a general provision in
the Articles or Regulations with respect to term of office, shall not be deemed
to create contract rights.

     SECTION 4.4 - REMOVAL. Any officer may be removed, with or without cause,
by the Board of Directors without prejudice to the contract rights, if any, of
such officer.

                                    ARTICLE V

                                   COMMITTEES

     SECTION 5.1 - GENERAL PROVISIONS FOR EXECUTIVE COMMITTEE. During such times
as all of the shareholders are directors, there shall be an Executive Committee.
At such time as fewer than all shareholders are directors, there may be the
Executive Committee, as the Board of Directors may from time to time decide.

     SECTION 5.2 - MEMBERSHIP OF THE EXECUTIVE COMMITTEE. During such time as
the existence of an Executive Committee is mandated by the provisions of
Section 5.1, the Executive Committee shall consist of six (6) members, and
shall include the following: the president and vice president of the
corporation, and chairmen of the pathology departments at Western Reserve
Care System and at St. Elizabeth Health Center, and the secretary and the
treasurer of the corporation. Until the earlier of (a) the elimination of the
Executive Committee by the decision of the shareholders, or (b) August 1,
2001, there shall be equal representation on the Executive Committee by
physicians whose regular duties are at Western Reserve Care System and by
physician whose regular duties are at St. Elizabeth Health Center. If the EX
OFFICIO designations provided for in this Section 5.2 do not fill the
Executive Committee, because, for example, one person is serving as one of
the above-referenced officers and also as a department chairman, then the
shareholders who are regularly practicing at the hospital at which such
person is regularly practicing shall designate an additional Executive
Committee member. At such time as the Executive Committee is no longer
mandatory, the membership on the Executive Committee shall be as the Board of
Directors shall determine. Those persons serving as EX OFFICIO members of the
Executive Committee shall serve while they hold their positions. Executive
Committee members who are elected by the shareholders at one of the
above-referenced hospitals may be removed at any time with or without cause
by the vote of a majority of such shareholders of such group, and a
replacement shall be chosen by them. Executive Committee members chosen by
vote shall serve for a term of one (1) year.

     SECTION 5.3 - AUTHORITY OF EXECUTIVE COMMITTEE. The Executive Committee
shall exercise the authority of the Board of Directors when so authorized by the
Board of Directors, and shall provide advice to the officers.

     SECTION 5.4 - OTHER COMMITTEES. The Board of Directors may establish other
committees consistent with this Code of Regulations as it may determine. All
aspects of the functioning of such committees shall be as determined by the
Board of Directors.

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                                   ARTICLE VI

                                 INDEMNIFICATION

     SECTION 6.1 - GENERAL PROVISIONS. The corporation may indemnity, to the
fullest extent now or hereafter permitted by law, any director or officer who
was or is a party or is threatened to be made a party to, or is involved in, any
threatened, pending or completed action, suit or proceeding, whether civil,
criminal, administrative or investigative (hereafter, a "proceeding"), by reason
of the fact that he or she, or a person of whom he or she is the legal
representative, is or was a director or officer of the corporation, or is or was
serving at the request of the corporation as a director, officer, partner,
trustee, employee or agent of another corporation, partnership, joint venture,
trust or other enterprise, including service with respect to employee benefit
plans, whether the basis of such proceeding is alleged action in an official
capacity as a director, officer, partner, .trustee, employee or agent or in any
other capacity while serving as a director, officer, partner, trustee, employee
or agent, against all expense, liability and loss (including attorneys' fees),
judgments, fines, excise taxes or penalties and amounts paid or to be paid in
settlement) reasonably incurred or suffered by such person in connection
therewith and such indemnification shall continue as to a person who has ceased
to be a director, officer, partner, trustee, employee or agent and shall inure
to the benefit of his or her heirs, executors and administrators. The extent to
which an indemnitee has a right to indemnification shall be as provided under
applicable law.

     SECTION 6.2 - PAYMENT OF EXPENSES. Expenses, including attorneys' fees,
incurred by a director or officer of the corporation in defending any proceeding
referred to in Section 6.1 hereof, may be paid by the corporation, in the
absolute discretion of the corporation, in advance of the final disposition of
such proceeding upon receipt of an undertaking by or on behalf of the director
or officer to repay such amount unless it shall ultimately be determined that
the or she is entitled to be indemnified by the corporation as authorized in
this Article VI; which undertaking may be secured or unsecured, at the
discretion of the corporation. The provisions of division 1701.13(E)(5)(a) (as
amended) of the Ohio Revised Code shall not apply to the corporation.

     SECTION 6.3 - ACTION TO COMPEL PAYMENT. If a claim under Section 6.1 hereof
is not paid in full by the corporation within thirty (30) days after a written
claim therefor has been received by the corporation, the claimant may at any
time thereafter bring suit against the corporation to recover the unpaid amount
of the claim and, if successful in whole or in part, the claimant shall be
entitled to also be paid the expense of prosecuting such claim. It shall be a
defense to any such action (other than an action brought to enforce a claim for
expenses incurred in defending any proceeding in advance of its final
disposition where the required undertaking, if any is required, has been
tendered to the corporation) that the claimant has not met the standards of
conduct which makes it permissible under the Ohio General corporation Laws for
the corporation to indemnify the claimant for the amount claimed, but the burden
of proving such defense shall be on the corporation. Neither the failure of the
corporation (including its Board of Directors, independent legal counsel, or its
shareholders) to have made a determination prior to the commencement of such
action that indemnification of the claimant is proper in the circumstances
because he or she has met the applicable standard of conduct set forth in the
Ohio General corporation Laws, nor an actual determination by the corporation

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(including its Board of Directors, independent legal counsel, or it
shareholders) that the claimant has not met such applicable standard or conduct,
shall be a defense to the action or create a assumption that the claimant has
not met the applicable standard or conduct.

     SECTION 6.4 - NONEXCLUSIVE REMEDY. The indemnification and advancement of
expenses provided under this Article VI shall not be deemed exclusive of any
other rights to which those seeking indemnification may be entitled under any
law, the Articles, these Regulations, any agreement, vote of shareholders or of
disinterested directors or otherwise, both as to action in their official
capacity and as to action in another capacity while holding such office.

     SECTION 6.5 - CONTRACTUAL OBLIGATION. This Article VI shall be deemed to be
a contract between the corporation and each director or officer of the
corporation, or individual who is or was serving at the request of the
corporation as a director, officer, partner, trustee, employee or agent of
another corporation, partnership, joint venture, trust or other enterprise, who
serves in such capacity at any time while this Article VI is in effect, and any
repeal, amendment or other modification of this Article VI shall not affect any
rights or obligations then existing with respect to any state of facts then or
theretofore existing or any action, suit or proceeding theretofore or thereafter
brought or threatened based in whole or in part upon any such state of facts.

     SECTION 6.6 - SAVINGS CLAUSE. If this Article VI or any portion thereof
shall be invalidated or found unenforceable on any ground by any court of
competent jurisdiction, then the corporation shall nevertheless indemnify each
director, officer, employee or agent of the corporation against expenses
(including attorneys' fees), judgments, fines, excise taxes, penalties and
amounts paid in settlement with respect to any action, suit or proceeding,
whether civil, criminal, administrative or investigative, to the full extent
permitted by any applicable portion of this Article VI that shall not have been
invalidated or found unenforceable, or by any other applicable law.

     SECTION 6.7 - INSURANCE. The corporation may maintain insurance, at its
expense, to protect itself and on behalf of any director, officer, employee or
agent of the corporation or individual serving at the request of the corporation
as a director, officer, partner, trustee, employee or agent of another
corporation, partnership, joint venture, trust or other enterprise against any
such expense, liability or loss, whether or not the corporation would have the
power to indemnify such person against such expense, liability or loss under the
Ohio General corporation laws.

                                   ARTICLE VII

                       SECURITIES HELD BY THE CORPORATION

     SECTION 7.1 - TRANSFER OF SECURITIES OWNED BY THE CORPORATION. All
endorsements, assignments, transfers, stock powers, share powers or other
instruments of transfer of securities standing in the name of the corporation
shall be executed for and in the

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name of the corporation by the president, a vice president, the secretary or (he
treasurer or any other person or persons as may be thereunto authorized by the
Board of Directors.

     SECTION 7.2 - VOTING SECURITIES HELD BY THE CORPORATION. The chairman of
the board, if any, president, any vice president, secretary or treasurer, in
person or by another person thereunto authorized by the Board of Directors, in
person or by proxy or proxies appointed by him or her, shall have full power and
authority on behalf of the corporation to vote, act and consent with respect to
any securities issued by other corporations which the corporation may own.

                                  ARTICLE VIII

                   CONSISTENCY WITH ARTICLES OF INCORPORATION

     If any provisions of these Regulations shall be inconsistent with the
corporation's Articles (and as they may be amended from time to time), the
Articles (as so amended at the time) shall govern.

                                   ARTICLE IX

                                   AMENDMENTS

     These Regulations may be amended, or new regulations may be enacted: (a) by
the affirmative vote of the holders of shares entitling them to exercise
seventy percent (70%) of the voting power of the corporation at any meeting
called for such purpose; or (b) without a meeting, by the written approval of
the holders of seventy percent (70%) of the voting shares of the corporation. In
the event of amendment or enactment of new regulations by such written consent,
the secretary of the corporation shall mail a copy of such amendment or new
regulations to each shareholder who did not participate in the approval thereof.

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                           AMERIPATH YOUNGSTOWN, INC.

                        AMENDMENTS TO CODE OF REGULATIONS

     The following provisions are applicable to and supplement the Sections
indicated and supercede anything to the contrary in the Code of Regulations:

SECTION 3.2 - NUMBER OF DIRECTORS. The number of directors shall be such number
as determined by the Board of Directors from a time to time within the limits
permitted under Section 1701.56 of the Ohio Revised Code.

SECTION 3.3 - ELECTION OF DIRECTORS. The first two sentences of Section 3.3 are
deleted and replaced with the following:

     No director is required to be a shareholder and no shareholder is required
to be a director.

SECTION 4.1- OFFICERS. All of Section 4.1 following the first sentence thereof
is deleted EXCEPT for the last sentence.

ARTICLE V - COMMITTEES. All of Article V is deleted EXCEPT for Section 5.4.

SECTION 6.3 is deleted.

SECTION 6.5 is deleted.