Does erythrocyte sedimentation rate (ESR) have diagnostic utility in my patient with chronic renal failure?

Short answer: often not! This is because most studies have shown frequently high ESR’s in stable “uninflamed” patients with chronic renal failure (CRF) (including those on dialysis) at levels often associated with infection, connective tissue disease, or malignancy. 1-4  

In fact, in a study involving patients with CRF, 57% of patients had markedly elevated ESR (greater than 60 mm/h), with 20% having ESR greater than 100 mm/h; type or duration of dialysis had no significant effect on ESR levels.1 Another study reported a specificity for abnormal ESR of only 35% for commonly considered inflammatory conditions (eg, infections or malignancy) among patients with CRF. 2

But is it the chronic inflammation in diseased kidneys or the uremic environment that elevates ESR? A cool study compared ESR in CRF in patients who had undergone bilateral nephrectomies with those with retained kidneys and found no significant difference in the ESR between the 2 groups. 4  So it looks like it’s the uremic environment, not diseased kidneys themselves that result in elevated ESR in these patients.

The mechanism behind these observations seem to reside entirely within the patients’ plasma, not the erythrocytes. Within the plasma, fibrinogen (not gammaglobulins) seem to be the most likely factor explaining elevated ESR among patients with CRF. 1,2

Bonus pearl:  Did you know that ESR is nearly 100 years old, first described in 1921? 5

References

  1. Barthon J, Graves J, Jens P, et al. The erythrocyte sedimentation rate in end-stage renal failure. Am J Kidney Dis 1987;10: 34-40. https://www.ncbi.nlm.nih.gov/pubmed/3605082
  2. Shusterman N, Morrison G, Singer I. The erythrocyte sedimentation rate and chronic renal failure. Ann Intern Med 1986;105:801. http://annals.org/aim/fullarticle/700910
  3. Arik N, Bedir A, Gunaydin M, et al. Do erythrocyte sedimentation rate and C-reactive protein levels have diagnostic usefulness in patients with renal failure? Nephron 2000;86:224. https://www.ncbi.nlm.nih.gov/pubmed/11015011
  4. Warner DM, George CRP. Erythrocyte sedimentation rate and related factors in end-stage renal failure. Nephron 1991;57:248. https://www.karger.com/Article/PDF/186266
  5. Fahraeus R. The suspension stability of the blood. Acta Med Scan 1921;55:70-92. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.0954-6820.1921.tb15200.x

 

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Does erythrocyte sedimentation rate (ESR) have diagnostic utility in my patient with chronic renal failure?

My patient with low back pain was just diagnosed with a lumbar spinal epidural abscess. Should I order an MRI of the rest of the spine?

First, look closely for any signs or symptoms which may suggest cord involvement due to spinal epidural abscess (SEA) at other levels of the spine (in this case cervical or thoracic) which would necessitate an urgent MRI. Be particularly on the lookout for new pain (particularly radicular) or paresthesias involving the abdomen, chest or upper extremities (with or without weakness)1.

Otherwise, whether an MRI of the entire spine should be routinely obtained after a diagnosis of SEA in the absence of any suggestive signs or symptoms is less clear, in part related to lack of properly designed studies.1-4

Nevertheless, a retrospective study involving 233 patients with SEA may shed some light on the subject. Based on 22 cases of noncontiguous SEA (9.4% of total), the following independent risk factors were identified3:

  • Delay in presentation (≥1 week of symptoms)
  • Concomitant area of infection outside the spine and paraspinal region
  • ESR > 95 mm/h at presentation

Probability of non-contiguous SEA based on the number of risk factors was as follows:

  • 3 risk factors: 73%
  • 2 risk factors: 13%
  • 1 risk factor: 2%
  • Zero risk factor: 0%

Despite several shortcomings and the need to confirm its findings2,3, this study helps raise awareness of the potential for concurrent but asymptomatic SEA elsewhere in the spine whenever SEA is diagnosed.

 

References

  1. Bond A, Manian FA. Spinal epidural abscess: a review with special emphasis on earlier diagnosis. BioMed Res International 2016;Volume 2016, Article ID 1614328. https://www.hindawi.com/journals/bmri/2016/1614328/
  2. Schoenfeld AJ, Hayward RA. Predicting modeling for epidural abscess: what we can, can’t, and should do about it. Spine J 2015;15:102-104. http://www.sciencedirect.com/science/article/pii/S152994301401554X
  3. Ju KL, Kim SD, Melikian R, et al. Predicting patients with concurrent noncontiguous spinal epidural abscess lesions. Spine J 2015;15:95-101. https://www.ncbi.nlm.nih.gov/pubmed/24953159
  4. Pfister HW, vonRosen F, Yousry T. MRI detection of epidural spinal abscesses at noncontiguous sites. J Neurol 1996;243:315-7. https://www.ncbi.nlm.nih.gov/pubmed/8965103
My patient with low back pain was just diagnosed with a lumbar spinal epidural abscess. Should I order an MRI of the rest of the spine?

When should I suspect spinal epidural abscess in my 55 year old patient with severe back pain?

 It cannot be overemphasized that up 50% of patients with spinal epidural abscess (SEA) have no known risk factors,  one-half may have no fever,  and 20-40% lack leukocytosis1. In fact, the “classic triad” of back pain, fever, and neurological deficits is found only in the minority of patients!  No wonder that up to 75% of patients SEA are misdiagnosed on their initial healthcare encounter1!

Potential “red flags” for infectious causes of low back pain include age >50 y, night pain, unremitting pain even when supine, duration > 6 weeks, fever, chills, night sweats, weight loss, conditions associated with Staphylococcus aureus bacteremia (eg intravenous drug use), incontinence, saddle anesthesia, and severe or rapidly progressive neurologic deficits1,2.  

ESR and C-reactive protein (CRP) are almost uniformly elevated in SEA1 and can serve as a good starting point in excluding this condition when in doubt.   In patients ≥50 y of age with low back pain, obtaining ESR routinely has been suggested for detection of systemic disease (eg cancer, infection)3.  Similarly, in a recent algorithm of severe back pain, routine measurements of ESR and CRP, even in the absence of any neurological findings, has been recommended1; elevation of either may necessitate consideration of MRI.

 

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References:

  1. Bond, A, Manian FA. Spinal epidural abscess: a review with special emphasis on earlier diagnosis. BioMed Res International 2016; https://www.hindawi.com/journals/bmri/2016/1614328/http://dx.doi.org/10.1155/2016/1614328  
  2. Della-Giustina. Acute low back pain: recognizing the “red flags” in the workup. Consultant 2013;53:436-440. http://www.consultant360.com/article/acute-low-back-pain-recognizing-%E2%80%9Cred-flags%E2%80%9D-workup
  3. Jarvik JG, Deyo RA. Diagnostic evaluation of low back pain with emphasis on imaging. Ann Intern Med 2002;137:586-597. http://annals.org/aim/article/715687/diagnostic-evaluation-low-back-pain-emphasis-imaging

 

Disclosure: The author of this post (FAM) also coauthored reference 1.

When should I suspect spinal epidural abscess in my 55 year old patient with severe back pain?

How do I interpret an elevated serum C-reactive protein (CRP) and normal erythrocyte sedimentation rate (ESR) or vice-versa?

 

Discordance between serum CRP and ESR is not uncommon (1,2). This phenomenon may be due to a variety of factors including the fact that the kinetics of these two tests is quite different, as discussed under “Should I order C-reactive protein (CRP) or erythrocyte sedimentation (ESR) on patients suspected of having a new infection?” in this blog.

In a study of CRP/ESR discordance (defined as results differing by 2 or 3 quartiles) in adults, a high CRP/low ESR profile was more likely to be associated with  urinary, GI, blood stream, and pulmonary infections, myocardial infarction, and venous thromboembolism and less likely to be associated with bone and joint infections (1).

In the same study, a high ESR/low CRP was associated with connective tissue diseases, such as systemic lupus erythematosus and strokes (1).

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References

1. Feldman M, Aziz B, Kang GN, et al. C-reactive protein and erythrocyte sedimentation rate discordance: frequency and causes in adults. Translational Research 2013;161:37-43. https://www.ncbi.nlm.nih.gov/pubmed/22921838

2. Colombet I, Pouchot J, Kronz V. Agreement between erythrocyte sedimentation rate and C-reactive protein in hospital practice. Am J Med 2010;123:864.e7-863.e13.https://www.ncbi.nlm.nih.gov/pubmed/20800157

How do I interpret an elevated serum C-reactive protein (CRP) and normal erythrocyte sedimentation rate (ESR) or vice-versa?