Which lab test should the nurse expect the healthcare provider to order for a client presenting with low-grade fever, arthralgias, fatigue, and facial rash?

In a clinical scenario where a patient presents with symptoms such as low-grade fever, arthralgias (joint pain), fatigue, and a facial rash, these manifestations are suggestive of an autoimmune disorder, particularly systemic lupus erythematosus (SLE).

The complete blood count (CBC) is crucial as it helps identify any anemia, leukopenia, or thrombocytopenia that commonly accompany SLE due to bone marrow involvement or autoimmune hemolysis. The antinuclear antibody (ANA) test is a specific and sensitive screening tool for autoimmune diseases. A positive ANA test is often found in individuals with SLE, indicating the presence of autoantibodies that target the body's own nuclear components. Therefore, ordering both the CBC and the ANA test provides essential information that aligns with the suspicion of SLE.

The other tests listed would not directly address the ongoing suspicion of an autoimmune process in this context. For instance, while a complete metabolic panel and liver function tests can be useful in assessing other conditions, they are less specific for autoimmune disorders. Similarly, a cholesterol and lipid profile, though important in assessing cardiovascular risk, would not help in diagnosing or assessing the autoimmune nature of the symptoms presented. Lastly, tests for BUN and