A 63 year old woman presents with 'aches and pains' in her knees, shoulders, and lower back for 3 months, in association with worsening fatigability. She has also lost weight during this time period, although the extent has not been measured.
Her medical, surgical, and family histories are unremarkable, and she is not on any medications. She does not smoke, drinks only socially, and is on a normal diet.
Her complete blood count is significant for a Hb of 9.5 g/dL, WBC of 3,800/mm3, and a platelet count of 115,000/mm3.
A follow up peripheral blood picture reveals a normocytic, normochromic anemia with marked rouleaux formation. Her ESR is 89 mm/1hr.