ESR of 2 mm/hour: Clinical Significance and Interpretation
An ESR of 2 mm/hour by the modified Westergren method is well within the normal range and effectively rules out significant systemic inflammation, inflammatory arthritis, or active inflammatory disease in this patient. 1
Normal Reference Values and Clinical Context
- ESR values are typically considered elevated when they exceed 20 mm/h in men and 30 mm/h in women, making a value of 2 mm/h markedly below any threshold for concern 1
- The patient's ESR of 2 mm/h falls far below even the most conservative cutoffs used for inflammatory conditions 2
- Normal ESR and CRP levels prompt serious reconsideration of active inflammatory disease, as these values are almost never normal in conditions like acute rheumatic fever, polymyalgia rheumatica, or active inflammatory arthritis (except in isolated chorea) 2
Interpretation in Context of Gout History
- The low ESR of 2 mm/h indicates this patient is not experiencing an acute gout flare, as acute inflammatory arthritis typically elevates ESR significantly 2
- The uric acid level of 3.8 mg/dL is actually below the typical diagnostic threshold for hyperuricemia (which varies by population but is generally >6 mg/dL for women and >7 mg/dL for men) 2
- Some individuals may have normal serum uric acid during intercritical periods of gout, as uric acid behaves as a negative acute phase reactant and can be temporarily lowered during acute attacks 2
- However, the combination of very low ESR (2 mm/h) and low uric acid (3.8 mg/dL) strongly suggests the patient is in an intercritical period with no active inflammation 2
Clinical Implications
This ESR value effectively excludes active inflammatory conditions including:
- Active inflammatory bowel disease (where ESR cutoffs of 10-15 mm/h are used for screening) 2
- Giant cell arteritis (where ESR >40 mm/h has 93.2% sensitivity) 1
- Polymyalgia rheumatica (where ESR >40 mm/h is typical) 2, 1
- Active rheumatoid arthritis or other inflammatory arthritides 2
- Adult-onset Still's disease (where ESR elevation occurs in 95-98% of cases) 1
No further inflammatory workup is indicated based on this ESR value alone 1
Important Caveats
- The modified Westergren method should use EDTA anticoagulated blood with saline diluent for optimal reproducibility, as undiluted techniques are less reliable 3
- While ESR can be affected by anemia and azotemia, a value this low (2 mm/h) would not be artificially suppressed by these conditions 1
- Women typically have higher baseline ESR values than men, and ESR normally increases with age, making this low value even more reassuring 1