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Christine Ahn MD
Carl Allen DDS, MSD
Brandon Ayres MD
Howard P. Baden MD
Robert Baran MD
Keira Barr MD
Gregory J. Basura MD, Ph.D
Donald Belsito MD
Jeffrey D. Bernhard MD
Jesse Berry MD
Victor Blanco MD
Benjamin R. Bohaty MD
William Bonnez MD
Sarah Brenner MD
Robert A. Briggaman MD
Robert Brodell MD
Roman Bronfenbrener MD
Walter Brooks MD
William Buckley MD
Philip Bulterys MD, PhD (candidate)
Susan Burgin MD
Sonya Burton MD
Sean P. Bush MD, FACEP
Jeffrey Callen MD
Scott Camazine MD
Michael Cardwell
Shelley D. Cathcart MD
Robert Chalmers MD, MRCP, FRCP
Chia-Yu Chu MD, PhD
Flavio Ciferri MD
Maria Rosa Cordisco MD
Noah Craft MD, PhD
John T. Crissey MD
Harold E. Cross MD, PhD
Charles Crutchfield III MD
Adriana Cruz MD
Donna Culton MD, PhD
Bart J. Currie MBBS, FRACP, DTM&H
Chicky Dadlani MD
Alexander Dane DO
C. Ralph Daniel III MD
Thomas Darling MD, PhD
William Delaney MD
Damian P. DiCostanzo MD
Ncoza Dlova MD
James Earls MD
Libby Edwards MD
Melissa K. Egge MD
Charles N. Ellis MD
Rachel Ellis MD
David Elpern MD
Nancy Esterly MD
Stephen Estes MD
E. Dale Everett MD
Janet Fairley MD
David Feingold MD
Benjamin Fisher MD
Henry Foong MBBS, FRCP
David Foster MD, MPH
Brian D. Foy PhD
Michael Franzblau MD
Vincent Fulginiti MD
Sunir J. Garg MD, FACS
Kevin J. Geary MD
Lowell Goldsmith MD, MPH
Sethuraman Gomathy MD
Bernardo Gontijo MD, PhD
Kenneth Greer MD
Kenneth G. Gross MD
Alan Gruber MD
Nathan D. Gundacker MD
Akshya Gupta MD
Vidal Haddad MSC, PhD, MD
Edward Halperin MD, MA
Ronald Hansen MD
John Harvey
Rizwan Hassan MD
Michael Hawke MD
Jason E. Hawkes MD
Peter W. Heald MD
David G. Hicks MD
Sarah Hocker DO
Ryan J. Hoefen MD, PhD
Li-Yang Hsu MD
William Huang MD
Sanjana Iyengar MD
Alvin H. Jacobs MD
Saagar Jadeja MD
Shahbaz A. Janjua MD
Joshua J. Jarvis MD
Kit Johnson
Robert Kalb MD
A. Paul Kelly MD
Henry Kempe MD
Loren Ketai MD
Sidney Klaus MD
Ashwin Kosambia MD
Jessica A. Kozel MD
Carl Krucke
Mario E. Lacouture MD
Joseph Lam MD
Alfred T. Lane MD
Edith Lederman MD
Nahyoung Grace Lee MD
Pedro Legua MD, PhD
Robert Levin MD
Bethany Lewis MD
Sue Lewis-Jones FRCP, FRCPCH
Taisheng Li MD
Christine Liang MD
Shari Lipner MD, PhD
Adam Lipworth MD
Jason Maguire MD
Mark Malek MD, MPH
Jere Mammino DO
Ricardo Mandojana MD
Lynne Margesson MD
Thomas J. Marrie MD
Maydel Martinez MD
Ralph Massey MD
Patrick McCleskey MD
Karen McKoy MD
Thomas McMeekin MD
Josette McMichael MD
Somchai Meesiri MD
Joseph F. Merola MD
Mary Gail Mercurio MD
Anis Miladi MD
Larry E. Millikan MD
Dan Milner Jr. MD
Zaw Min MD
Stephanie Montero
Alastair Moore MD
Keith Morley MD
Dean Morrell MD
Samuel Moschella MD
Taimor Nawaz MD
Vic Newcomer MD
John Nguyen MD
Matilda Nicholas MD
Thomas P. Nigra MD
Steven Oberlender MD, PhD
Maria Teresa Ochoa MD
Art Papier MD
Lawrence Parish MD
Tanner Parrent MD
Mukesh Patel MD
Lauren Patty-Daskivich MD
David Peng MD, MPH
Robert Penne MD
Nitipong Permpalung MD
Miriam Pomeranz MD
Doug Powell MD
Harold S. Rabinovitz MD
Christopher J. Rapuano MD
Sireesha Reddy MD
Angela Restrepo MD, PhD
Bertrand Richert MD, PhD
J. Martin Rodriguez, MD, FACP
Theodore Rosen MD
Misha Rosenbach MD
Scott Schiffman MD
Robert H. Schosser MD
Glynis A. Scott MD
Carlos Seas MD, MSc
Deniz Seçkin MD
Daniel Sexton MD
Paul K. Shitabata MD
Tor Shwayder MD, FAAP, FAAD
Elaine Siegfried MD
Gene Sienkiewicz MD
Christye Sisson
Philip I. Song MD
Mary J. Spencer MD, FAAP
Lawrence B. Stack MD
Sarah Stein MD
William Van Stoecker MD
Frances J. Storrs MD
Erik J. Stratman MD
Lindsay C. Strowd MD
Erika Summers MD
Belinda Tan MD, PhD
Robert Tomsick MD
Hensin Tsao MD, PhD
Jenny Valverde MD
Vishalakshi Viswanath MD
Susan Voci MD
Lisa Wallin ANP, FCCWS
Douglas Walsh MD
Ryan R. Walsh MD
George Watt MD
Clayton E. Wheeler MD
Sally-Ann Whelan MS, NP, CWOCN
Jan Willems MD, PhD
James Henry Willig MD, MPH
Karen Wiss MD
Vivian Wong MD, PhD
Sook-Bin Woo MS, DMD, MMSc
Jamie Woodcock MD
Stephen J. Xenias MD
Lisa Zaba MD
Vijay Zawar MD
Bonnnie Zhang MD
Carolyn Ziemer MD
Organizations
Am. Journal of Trop. Med & Hygiene
Armed Forces Pest Management Board
Blackwell Publishing
Bugwood Network
Centers For Disease Control and Prevention
Centro Internacional de Entrenamiento e Investigaciones Mèdicas (CIDEIM)
Dermatology Online Journal
East Carolina University (ECU), Division of Dermatology
Psoriatic arthritis (PsA) is an inflammatory arthritis that occurs in up to 30% of psoriatics. It is typically considered a seronegative inflammatory arthritis, ie, without detectable rheumatoid factor. About 15% of patients develop PsA before skin psoriasis is present.
The etiology of the disease is multifactorial, with both genetic and environmental factors. PsA affects men and women equally and is predominantly seen in white individuals, similar to psoriasis.
Symptoms:
Pain, stiffness in affected joints, with joint stiffness present for >30 minutes in the morning (after waking) or after prolonged inactivity. Improves with activity (versus osteoarthritis / degenerative joint disease, which typically worsens with activity).
With axial involvement – Inflammatory back pain and stiffness that improve with activity; night symptoms can cause waking from sleep; decreased range of motion of the axial spine and neck over time.
Tender / painful; swelling at entheses (sites of tendon insertion into bone).
Tendonitis / tenosynovitis
Ocular inflammation may lead to scleral erythema, dry eye / foreign body sensation, or uveitis with potential visual disturbance and pain.
Signs:
Tender, painful, swollen joints with possible erythema, effusion, and warmth noted in more actively inflamed joints.
Dactylitis – Inflammation and swelling of the entire digit including metacarpophalangeal (MCP) through proximal / distal interphalangeal (PIP/DIP) joints and intervening soft tissue, giving a "sausage digit" appearance.
Enthesitis – Inflammation at tendinous insertion into bone, with tenderness.
Note: Patients do not necessarily fit into any one pattern and may have features of several throughout the course of illness.
Risk factors:
Patients with nail, scalp, and inverse (intertriginous) psoriatic skin disease have a higher risk of developing PsA.
Several genetic risk markers (HLA associations) are associated with development and variable prognosis in PsA.
Timeline:
Progression to PsA among patients with psoriasis has been reported to occur at a rate of around 2% per year.
Episodic flares of the disease in addition to chronic, baseline joint inflammation.
Joint erosion / damage may accrue over time, with the potential for development of functional impairments.
Accepted CASPAR criteria (ClASsification criteria for Psoriatic ARthritis) are routinely used to classify patients with PsA for trials and studies and may also aid in diagnosis of patients. These include the presence of psoriasis skin lesions, a family history of psoriasis, nail lesions, dactylitis, absence of rheumatoid factor, and periarticular bone formation on radiographs, with a point system to grade each feature (refer to CASPAR criteria; see References).
Codes
ICD10CM: L40.59 – Other psoriatic arthropathy
SNOMEDCT: 33339001 – Psoriasis with arthropathy
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Differential Diagnosis & Pitfalls
Rheumatoid arthritis (RA) – Symmetric polyarthritis; presentation, clinical course, and radiologic and serologic features are distinct from PsA (may be rheumatoid factor and anti-cyclic citrullinated peptide [anti-CCP] positive). The absence of DIP involvement, asymmetry, axial involvement, dactylitis, skin psoriasis, psoriatic nail disease, and radiography may help distinguish RA from PsA.
Gout – History of podagra, joint fluid from arthrocentesis demonstrating monosodium urate crystal should help to differentiate; gout and psoriasis / PsA may co-exist, however.
Pseudogout – Chondrocalcinosis on radiographs and calcium pyrophosphate crystals on joint fluid examination.
Reactive arthritis – Would not expect the presence of psoriasis skin disease; associated with other symptoms such as preceding genitourinary symptoms, diarrheal illness, and skin findings such as keratoderma blenorrhagicum.
Ankylosing spondylitis – To be distinguished from axial disease in PsA; PsA tends to have an asymmetric involvement of the sacroiliac joints, formation of "jug-handle" nonmarginal syndesmophytes that are asymmetrically located, skip lesions along the spine (cervical > lumbar involvement).
Fibromyalgia – Diffuse widespread pain involving "tender point" soft tissue areas. Synovitis is not a component of fibromyalgia. It is important to distinguish enthesitis (inflammation at sites of tendon insertion into bone) from the tender points of fibromyalgia, eg, near the lateral epicondyle of the upper extremity. Fatigue may be common to both conditions. Stiffness may be reported but does not improve with activity.
