THE CASE
A 43-year-old Black male presented to his primary care physician with an 8-month history of progressive fatigue, weakness, and unintentional weight loss. The patient’s history also included antiphospholipid antibody syndrome (APS) with prior deep venous thrombosis/pulmonary embolism for which he was taking warfarin.
At the time of presentation, he reported profound dyspnea on exertion, lightheadedness, dry mouth, low back pain, and worsening nocturia. The remainder of the review of systems was negative. He denied tobacco, alcohol, or illicit drug use or recent travel. His personal and family histories were negative for cancer.
Laboratory data collected during the outpatient visit were notable for a white blood cell count of 2300/mcL (reference range, 4000-11,000/mcL); hemoglobin, 8.6 g/dL (13.5-17.5 g/dL); and platelets, 44,000/mcL (150,000-400,000/mcL). Proteinuria was indicated by a measurement > 500 mg/dL on urine dipstick.
The patient was admitted to the hospital for further work-up of new pancytopenia. His vital signs on admission were notable for tachycardia and a weight of 237 lbs, decreased from 283 lbs 8 months prior. His physical exam revealed dry mucous membranes, bruising of fingertips, and marked lower extremity weakness with preserved sensation. No lymphadenopathy was noted on the admission physical exam.
THE DIAGNOSIS
Inpatient laboratory studies showed elevated inflammatory markers and a positive Coombs test with low haptoglobin. There was no evidence of bacterial or viral infection. Computed tomography of the chest, abdomen, and pelvis revealed axillary, subpectoral, and pelvic lymphadenopathy (see FIGURE). A work-up for multiple myeloma was negative, and a bone marrow biopsy was nondiagnostic.
Autoimmune laboratory data included a positive antiphospholipid antibody (ANA) test (1:10,240, diffuse; reference < 1:160), an elevated dsDNA antibody level (800 IU/mL; reference range, 0-99 IU/mL), low complement levels, and antibody titers consistent with the patient’s known APS. Based on these findings, the patient was given a diagnosis of systemic lupus erythematosus (SLE).
DISCUSSION
Lymphadenopathy, revealed by exam or by imaging, in combination with systemic symptoms such as weight loss and fatigue, elicits an extensive differential diagnosis. In the absence of recent exposures, travel, or risk factors for infectious causes, our patient’s work-up was appropriately narrowed to noninfectious etiologies of pancytopenia and lymphadenopathy. At the top of this differential are malignancies—in particular, multiple myeloma and lymphoma—and rheumatologic processes, such as sarcoidosis, connective tissue disease, and SLE.1,2 Ultimately, the combination of autoimmune markers with the pancytopenia and a negative work-up for malignancy confirmed a diagnosis of SLE.
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