These include not just Rheumatoid Arthritis or Systemic Lupus Erythematosus (SLE, Lupus), but also a variety of other diseases which can cause fatigue, joint pains, or body aches. Many cause other specific symptoms to clue us in, like arthritis, recurrent bloody nose, etc. etc. But if all the patient feels is fatigue or achiness, we don’t go ordering bunches of tests, because even if some of them were positive, they’d likely be false positive. Nobody wants an invasive biopsy done because a screening test was false-positive.
But we do seek some simple clues for possible obscure diseases, and if we find such clues, we plan additional work-ups. Some of these clues include:
- Complete Blood Count: for abnormalities in red blood cells, white blood cells, or platelets
- Elevated Sed Rate or C-Reactive Protein
- Signs of decreased kidney function (blood test for Creatinine; urinalysis for blood or protein)
- Vasculitis, an inflammation of the arteries. This can occur in any organ. Symptoms can be general, such as fatigue, joint pains, fevers, weight loss, and strange rashes. Bleeding or symptoms in any specific organ might occur. A main diagnostic test is called an ANCA.
- Relapsing Polychondritis, inflammation of cartilage. One key sign might be red painful ears (on the outside).
- Mixed Connective Tissue Disease, which includes symptoms common to Lupus, Sjögren’s Syndrome, Raynaud’s Phenomenon, scleroderma, and also muscle pain / weakness, heart & lung problems, and more.
- Paraneoplastic Syndrome — People with cancer, often not yet diagnosed, may develop unusual symptoms having nothing to do with the part of the body where the tumor is. These may include fatigue, joint pains, changes in sensation, visual changes, memory problems, rashes, and more. Unfortunately, studies show that it isn’t productive to do a wide range of tests like groping in the dark; in fact, when clinicians do so, we say they’ve ordered a “grope-o-gram.”