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Overlap syndromes

Last reviewed: 12 Nov 2024
Last updated: 14 Nov 2023

Summary

Definition

History and exam

Key diagnostic factors

  • digital pallor/pain
  • arthritis/arthralgia
  • swollen hands
  • sclerodactyly
  • nail fold vascular changes
  • dyspnea or cough
  • GERD and heartburn
  • myalgias or myositis
Full details

Other diagnostic factors

  • hematuria
  • lymphadenopathy
  • alopecia
  • skin rashes
  • proximal muscle weakness
  • trigeminal neuralgia
  • headaches
  • neuropsychiatric disease including psychosis and seizures
  • peripheral neuropathy
  • fever
Full details

Risk factors

  • female sex
  • age 20 to 40 years
  • presence of specific HLA genotypes
Full details

Diagnostic tests

1st tests to order

  • CBC
  • erythrocyte sedimentation rate
  • CRP
  • serum BUN and creatinine
  • rheumatoid factor
  • antinuclear antibodies
  • anti-cyclic citrullinated peptide (anti-CCP) antibody
  • urinalysis
  • anti-U1 ribonucleoprotein
  • anti-Jo-1
Full details

Tests to consider

  • creatine kinase
  • anti-double-stranded DNA
  • Smith antigen
  • anti-SS-A and anti-SS-B
  • additional antibody tests (anti-Scl 70, anticentromere antibodies, anti-RNA polymerase III, anti-PM/Scl antibodies)
  • pulmonary function tests (spirometry, lung volumes and diffusion capacity measurement)
  • CXR
  • high-resolution CT scan of chest
  • echocardiogram
  • right-heart catheterization
  • barium swallow
  • upper gastrointestinal endoscopy ± biopsy
  • plain x-ray of affected joint(s)
  • electromyography
  • nerve conduction studies
  • muscle biopsy
  • lung biopsy
  • renal biopsy
Full details

Emerging tests

  • anti-Ku antibodies
  • other antisynthetase antibodies (PL7, PL12, OJ, EJ, KS, Ha and others)

Treatment algorithm

ONGOING

all patients

Contributors

Authors

Larry Young, MD

Associate Professor of Medicine

Division of Rheumatology

Miller School of Medicine

University of Miami

Miami

FL

Disclosures

LY declares that he has no competing interests.

Carlos Lozada, MD

Associate Professor of Medicine

Division of Rheumatology and Immunology

Miller School of Medicine

University of Miami

Miami

FL

Disclosures

CL declares that he has no competing interests.

Acknowledgements

Dr Larry Young and Dr Carlos Lozada would like to gratefully acknowledge Dr Robert Hoffman, a previous contributor to this topic.

Disclosures

RH has received NIH grants greater than 6 figures USD. RH is the author of some studies referenced in this topic. RH declares that he has no competing interests.

Peer reviewers

Robert Ortmann, MD

Associate Professor and Director

Division of Rheumatology and Immunology

University of Arkansas for Medical Sciences

Little Rock

AR

Disclosures

RO declares that he has no competing interests.

Alan Bridges, MD

Professor and Vice Chair

Department of Medicine

University of Wisconsin Hospital

Madison

WI

Disclosures

AB declares that he has no competing interests.

Simon Bowman, PhD, FRCP

Consultant Rheumatologist and Honorary Senior Clinical Lecturer in Rheumatology

Selly Oak Hospital

Birmingham

UK

Disclosures

SB declares that he has no competing interests.

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