A 35-Year-Old Woman Comes to the Physician with 2 Months

A 35-year-old woman comes to the physician with 2 months of arm and leg weakness accompanied by puffy swelling of her hands.  She also complains of dry eyes and mouth.  She reports that her fingers turn blue or white when exposed to cold temperatures.  The patient was evaluated for fatigue 6 months ago and was found to have normal complete blood count, serum chemistry, thyroid-stimulating hormone, vitamin D level, erythrocyte sedimentation rate, and C-reactive protein.  Her antinuclear antibody test was positive at a low titer 1:80.
She was advised to increase her aerobic activity level and was prescribed myofascial stretching exercises.  She has no other significant past medical history.  Her medications include acetaminophen and oral contraceptive pills.  The patient drinks alcohol occasionally but does not use tobacco or illicit drugs.  She works on a factory assembly line and has 3 children.
Vital signs are within normal limits.  On examination, she has several telangiectasias in the face.  Both hands appear edematous and there is synovitis in several metacarpophalangeal and proximal interphalangeal joints.  There is no leg edema.  Muscle strength is decreased symmetrically and is 4/5 in both upper and lower extremities.
Laboratory results are as follows:

Which of the following antibodies is most likely to be positive in this patient?

A) Antibodies to aminoacyl-tRNA synthetases
B) Antibodies to topoisomerase
C) Anti-double-stranded DNA antibodies
D) Anti-neutrophil cytoplasmic antibodies
E) Anti-U1-RNP (ribonucleoprotein) antibodies