The erythrocyte sedimentation rate (ESR) is a commonly performed test but is very nonspecific, which means that having a high ESR does not necessarily tell your physician what is wrong, only that something may be wrong. The ESR is a marker of inflammation, so it can be high with infections and also other types of inflammation. The ESR can even be mildly elevated when you are completely healthy.
Fever is a common symptom that occurs with an elevated ESR. Fever often occurs with different types of infection, but can also be present in other inflammatory conditions, such as certain types of arthritis, cancer and drug reactions.
Many different types of infections can be associated with a high ESR. These include common infections such as viral syndromes (the "cold" or influenza), strep throat or cellulitis (a skin infection). Very high ESR (>100 mm/hour) can be associated with more serious infections such as endocarditis (heart infection) or septic arthritis (joint infection).
Joint pain can occur with arthritis (inflammation of the joint) or infection (see previous section). Certain types of arthritis are associated with inflammatory conditions or autoimmune conditions (when the body's immune system attacks itself). Common types of inflammatory arthritis that cause a high ESR include gout, rheumatoid arthritis and systemic lupus erythematosus (lupus or SLE).
Rash can occur with viral illnesses or with autoimmune conditions that will also cause a high ESR. Lupus is one autoimmune condition that causes both a rash and an elevated ESR. A rash can also occur with something called vasculitis, which is inflammation of the blood vessels.
Headache is very non-specific, meaning that it can occur in a lot of different diseases. Several of these diseases or illnesses can also cause a high ESR. Infection can cause a headache and a high ESR. Viral infections can be associated with headache. More serious infections such as bacterial meningitis (infection of the covering of your brain) which are potentially life threatening can also cause a headache. Headache can also be associated with inflammatory conditions like lupus. Finally, headache (specifically pain over the temple) along with visual changes in older adults can be associated with a condition called temporal arteritis, a type of vasculitis. This condition almost always causes a very high ESR.
Sore throat is a common symptom and usually a result of an infection, such as strep throat or mononucleosis (mono). Sometimes throat infections get so severe that they need to be surgically drained or treated in the hospital. All of these types of infection can cause a high ESR and generally the worse the infection, the higher the ESR. So, a strep throat (a fairly minor infection) may cause a slightly elevated ESR while a serious throat infection requiring surgery may cause a much higher ESR.
Fatigue, or feeling tired, is a very common symptom that can be associated with a high ESR. Fatigue can be caused by anemia (low blood count), pregnancy, cancer, infection or inflammation--all of which can also cause a high ESR.