Patient A has no known allergies and takes no prescription or over-the-counter medication aside from occasional naproxen for joint pain and antacid for heartburn. She neither smokes nor drinks alcohol. Her youngest child is 2 years of age, and she reports unremarkable childbirths and postpartum periods. Aside from the current complaints, the patient's medical history is unremarkable.

She has four brothers and three sisters. The family history indicates an older sister with rheumatoid arthritis, an aunt with pernicious anemia, and mother with hyperthyroidism.

The primary care provider conducts a full physical assessment (Table 2). Several laboratory tests are ordered, with the following results:

Further, a tissue biopsy of one of the lesions is taken and reveals vasculitis (i.e., white blood cells within the walls of blood vessels).

Based on the results of the assessment and laboratory studies, Patient A is diagnosed with SLE.

A one-month course of prednisone with tapered doses is prescribed. Nabumetone, an anti-inflammatory, is added to the regimen prior to the prednisone being weaned off. After one month of treatment, all signs and symptoms of lupus have resolved.

However, 13 years later, Patient A again presents to her primary care provider, this time with complaints of a productive cough and transient stiffness and pain in her hands and feet (migratory polyarthritis). She is afraid that she is developing rheumatoid arthritis like her sister. The provider conducts a physical examination (Table 3) and is concerned that the patient may be showing signs of pneumonia. A chest x-ray revealed mild pulmonary edema but no white blood cell infiltrates in the terminal airways. Laboratory tests reveal:

Patient A is diagnosed as experiencing a lupus flare and is prescribed a one-month course of prednisone along with a 10-day course of antibiotics to prevent pneumonia. Within three months, all signs and symptoms have resolved.

Five years later, Patient A returns to her primary care provider complaining of fatigue, anorexia, weight loss (25 pounds in the last four months), and significant swelling in her abdomen, face, and ankles. The nurse practitioner notes a "butterfly-shaped" rash present across the bridge of the patient's nose and cheeks. Blood tests reveal an HCT of 24% and a WBC count of 2,400 cells/mcL. A dipstick examination of the urine reveals an abnormal protein concentration, and microscopy indicates the presence of significant numbers of red and white blood cells. A 24-hour urine protein collection reveals excretion of 2.5 g protein in 24 hours.

The primary care provider does a complete physical exam (Table 4) and orders laboratory tests. The laboratory blood test results are:

A urinalysis is performed and is normal, with no RBCs, WBCs, or protein. A chest x-ray finds no fluid, masses, infection, or cardiomegaly. An x-ray of the hand shows soft tissue swelling and bone demineralization but no erosions. Synovial fluid removed from the left knee (7.4 mL) is cloudy and pale yellow in appearance; analysis indicates 14,000 white blood cells/mcL (primarily neutrophils) and a glucose level of 60 mg/dL.

Based on these findings, Patient C is diagnosed with rheumatoid arthritis and referred to a rheumatologist for follow-up.