Clinical profile of anti-PL-12 autoantibody. Cohort study and review of the literature.
BACKGROUND
The antisynthetase syndrome consists of interstitial lung disease (ILD), arthritis, myositis, fever, mechanic's hands, and Raynaud phenomenon in the presence of an antisynthetase autoantibody, most commonly anti-Jo-1. It is believed that all the antisynthetases are associated with a similar clinical profile, but definitive data in this diverse group are lacking. The purpose of this study was to examine the clinical profile of anti-PL-12, an antisynthetase autoantibody directed against alanyl-transfer RNA synthetase.


METHODS
Thirty-one subjects with anti-PL-12 autoantibody were identified from the databases at the Medical University of South Carolina, the University of Pittsburgh Medical Center, Johns Hopkins Medical Center, and Brigham and Women's Hospital. The medical charts were reviewed and the following data were recorded: demographic information; pulmonary and rheumatologic symptoms; connective tissue disease (CTD) diagnoses; serologic autoantibody findings; CT scan results; BAL findings; pulmonary function test results; lung histopathology; and treatment interventions.


RESULTS
The median age at symptom onset was 51 years; 81% were women and 52% were African American. Ninety percent of anti-PL-12-positive patients had ILD, 65% of whom presented initially to a pulmonologist. Ninety percent of anti-PL-12-positive patients had an underlying CTD. Polymyositis and dermatomyositis were the most common underlying diagnoses. Raynaud phenomenon occurred in 65% of patients, fever in 45% of patients, and mechanic's hands in 16% of patients. Test results for the presence of antinuclear antibody were positive in 48% of cases.


CONCLUSIONS
Anti-PL-12 is strongly associated with the presence of ILD, but less so with myositis and arthritis. Idiopathic ILD diagnosed as idiopathic pulmonary fibrosis may, in fact, be associated with anti-PL-12 and be a "forme fruste" of an underlying autoimmune disorder.
Kalluri
Meena
M
Division of Pulmonary and Critical Care Medicine, Allergy, and Sleep Medicine, Medical University of South Carolina, Charleston, SC. Electronic address: meenakalluri@med.ualberta.ca.
Sahn
Steven A
SA
Division of Pulmonary and Critical Care Medicine, Allergy, and Sleep Medicine, Medical University of South Carolina, Charleston, SC.
Oddis
Chester V
CV
Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, PA.
Gharib
Suzanne L
SL
Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, PA.
Christopher-Stine
Lisa
L
Divisions of Rheumatology, Johns Hopkins University, Baltimore, MD.
Danoff
Sonye K
SK
Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD.
Casciola-Rosen
Livia
L
Divisions of Rheumatology, Johns Hopkins University, Baltimore, MD.
Hong
Grace
G
Divisions of Rheumatology, Johns Hopkins University, Baltimore, MD.
Dellaripa
Paul F
PF
Division of Rheumatology, Allergy, and Immunology, Brigham and Women's Hospital, Boston, MA.
Highland
Kristin B
KB
Division of Pulmonary and Critical Care Medicine, Allergy, and Sleep Medicine, Medical University of South Carolina, Charleston, SC.
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000604:Amino Acyl-tRNA Synthetases / Q000276:immunology*; D001168:Arthritis / Q000150:complications / Q000276:immunology; D001323:Autoantibodies / Q000276:immunology*; D001327:Autoimmune Diseases / Q000175:diagnosis* / Q000453:epidemiology; D015331:Cohort Studies; D005260:Female; D005334:Fever / Q000150:complications / Q000276:immunology; D006225:Hand / Q000503:physiopathology; D006801:Humans; D015994:Incidence; D017563:Lung Diseases, Interstitial / Q000150:complications / Q000276:immunology; D008297:Male; D008875:Middle Aged; D017285:Polymyositis / Q000150:complications / Q000276:immunology; D011379:Prognosis; D011928:Raynaud Disease / Q000150:complications / Q000276:immunology; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D012737:Sex Factors; D013577:Syndrome; D055815:Young Adult
D001323:Autoantibodies; D000604:Amino Acyl-tRNA Synthetases