Systemic lupus erythematosus Sjögren syndrome scleroderma

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A 57-year-old woman with a history of hypertension and arthritis is referred to a rheumatologist for evaluation. A complete blood count (CBC) is normal, and a mini-chem panel shows no electrolyte abnormalities. Her erythrocyte sedimentation rate (ESR) is elevated, and an antinuclear antibody test (ANA) is positive. Further antibody studies are performed, and the results are shown below.

Anti-histones high titer

Anti-double stranded DNA not detected

Anti-single stranded DNA not detected

Anti-SSA not detected

Anti-SSB not detected

Anti-SCI-70 not detected

Anti-Smith not detected

Anti-centromere not detected

Anti-RNP not detected


Which of the following diseases is suggested by these results?


(A) CREST syndrome
(B) Diffuse form of scleroderma
(C) Drug-induced lupus
(D) Sjögren syndrome
(E) Systemic lupus erythematosus

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Is it drug-induced lupus?

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Originally Posted by usmlequestions

A 57-year-old woman with a history of hypertension and arthritis is referred to a rheumatologist for evaluation. A complete blood count (CBC) is normal, and a mini-chem panel shows no electrolyte abnormalities. Her erythrocyte sedimentation rate (ESR) is elevated, and an antinuclear antibody test (ANA) is positive. Further antibody studies are performed, and the results are shown below.

Anti-histones high titer

Anti-double stranded DNA not detected

Anti-single stranded DNA not detected

Anti-SSA not detected

Anti-SSB not detected

Anti-SCI-70 not detected

Anti-Smith not detected

Anti-centromere not detected

Anti-RNP not detected


Which of the following diseases is suggested by these results?


(A) CREST syndrome
(B) Diffuse form of scleroderma
(C) Drug-induced lupus
(D) Sjögren syndrome
(E) Systemic lupus erythematosus

The correct answer is C. Drug-induced lupus.

The correct answer is C. The single finding of high autoantibody titers to histones, without any other autoantibodies, is characteristic of drug-induced lupus. The most commonly implicated drugs are procainamide, hydralazine (given for hypertension), and isoniazid. Patients typically have milder disease than in systemic lupus erythematosus (SLE) and tend to have arthritis, pleuropericardial involvement, and, less commonly, rash. CNS and renal disease are not usually observed.

CREST syndrome (choice A) is a milder variant of scleroderma characterized by calcinosis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly and telangiectasia. Anti-centromere antibodies are diagnostic.

The diffuse form of scleroderma (choice B), also known as systemic sclerosis, causes fibrosis of the skin and internal viscera. This disorder is characterized by anti-SCI-70 and often low titers of many other autoantibodies.

Sjögren syndrome (choice D) is characterized by dry eyes and dry mouth. Sjögren syndrome in isolation is characteristically positive for anti-SS-A and anti-SS-B. If it accompanies rheumatoid arthritis, anti-RNP will be positive as well.

SLE (choice E) is a multisystem disorder that is distinguished from drug-induced lupus by the presence of a wide variety of autoantibodies, including anti-double stranded DNA (Anti dsDNA).