The most likely diagnosis is limited cutaneous systemic sclerosis (LcSSc), a form of systemic sclerosis that is characterized by distal (face, neck, and hands) but not proximal skin thickening and is typically not accompanied by internal organ fibrosis. Patients with LcSSc may display features of the CREST (calcinosis cutis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia) syndrome and are more likely to develop Raynaud phenomenon early in the disease course. Pulmonary arterial hypertension is more common in patients with LcSSc compared with diffuse cutaneous systemic sclerosis. This patient presents with skin thickening involving the distal extremities and face as well as Raynaud phenomenon; he also has nodules on the extremities, which are suggestive of calcinosis cutis. A number of patients may present with only one or two clinical features, and negative serologies (including antinuclear antibodies) are seen in up to 10% to 25% of patients with LcSSc. He does not have CREST syndrome, which is a variant of LcSSc characterized by the presence of telangiectasias and esophageal dysmotility as well as positive antinuclear and anticentromere antibodies.

Eosinophilia myalgia syndrome is characterized by fasciitis and dermal induration linked to consuming contaminated L-tryptophan, a nutritional supplement. Patients also develop neuropathy and myopathy but not Raynaud phenomenon or scleroderma-specific autoantibodies. New cases are rare since the identification of the toxin several years ago. This patient consumes no nutritional supplements and has Raynaud phenomenon, making eosinophilia myalgia syndrome unlikely.

Morphea is characterized by a localized area of skin thickening, usually on the torso; systemic manifestations or Raynaud phenomenon is extremely rare in patients with this condition.

Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease of unknown cause affecting middle-aged women. Fatigue, dry eyes, dry mouth, and pruritus are the most common symptoms. Jaundice, cutaneous hyperpigmentation, hepatosplenomegaly, and xanthelasmas are rarely observed at diagnosis. Raynaud phenomenon and skin thickening are not consistent with PBC.