A Case Report of Acquired Factor X Deficiency in a Patient With Multiple Myeloma.

Multiple myeloma is a plasma cell neoplasm characterized by clonal proliferation of immunoglobulin producing terminally differentiated B cells. Classically patients are described to present with bone pain, hypercalcemia, anemia, and/or renal impairment. A less described clinical manifestation related to the myeloma is acquired coagulation abnormalities including paraprotein interfering with the coagulation cascade or exhibiting specific antibody activity. Factor X deficiency is reported in patients with secondary amyloidosis. We describe a patient who presented with bleeding tendency and an abnormal prothrombin and activated partial thromboplastin times (PT/PTT) due to factor X deficiency. A thorough workup revealed the diagnosis of multiple myeloma with the presence of monoclonal lambda light chain restricted plasma cells with qualifying end-organ damage without evidence of amyloidosis. Prior to the ultimate diagnosis, the patient succumbed to septic shock and acute respiratory distress syndrome due to Streptococcus Pneumonia infection.