Schumacher criteria

Multiple sclerosis, understood as a CNS condition, can be difficult to diagnose since its signs and symptoms may be similar to other medical problems.^[1] Medical organizations have created diagnostic criteria to ease and standardize the diagnostic process especially in the first stages of the disease. Schumacher criteria were the first internationally recognized criteria for diagnosis, and introduced concepts still in use, as CDMS (Clinically definite MS).

Sometimes it has been stated that the only proved diagnosis of MS is autopsy, or occasionally biopsy, where lesions typical of MS can be detected through histopathological techniques, and that sensitivity and specificity should be calculated for any given criteria^[2][3]

Context

Historically, the first widespread set of criteria were the Schumacher criteria (also spelled sometimes Schumacker). Currently, testing of cerebrospinal fluid obtained from a lumbar puncture can provide evidence of chronic inflammation of the central nervous system, looking for oligoclonal bands of IgG on electrophoresis, which are inflammation markers found in 75–85% of people with MS.^[2][4], but at the time of Schumacher criteria, oligoclonal bands tests were not available, and they also lacked MRI.

The most commonly used diagnostic tools at that time were evoked potentials. The nervous system of a person with MS responds less actively to stimulation of the optic nerve and sensory nerves due to demyelination of such pathways. These brain responses can be examined using visual and sensory evoked potentials.^[5]

Therefore, clinical data alone had to be used for a diagnosis of MS. Schumacher et al. proposed three classifications based in clinical observation: CDMS (clinically definite), PrMS(probable MS) and PsMS(possible MS).^[6]

Summary

To get a diagnosis of CDMS a patient must show the following^[7]:

1. Clinical signs of a problem in the CNS
2. Evidence of two or more areas of CNS involvement
3. Evidence of white matter involvement
4. One of these: Two or more relapses (each lasting ≥ 24 hr and separated by at least 1 month) or progression (slow or stepwise)
5. Patient should be between 10 and 50 yr old at time of examination
6. No better explanation for patient’s symptoms and signs

The last condition, no better explanation for symptoms, has been heavily criticised, but it has been preserved and it is currently included in the new McDonalds criteria in the form that "no better explanation should exist for MRI observations"

Influence

These criteria were later substituted by Poser criteria and McDonald criteria.^[8]. Poser criteria introduced the CNS oligoclonal bands into the diagnosis criteria, while McDonald criteria focus on a demonstration with clinical, laboratory and radiologic data of the dissemination of MS lesions in time and space for non-invasive MS diagnosis. All the later criteria were heavily influenced by the original Schumacher work.

References

1. ^ Trojano M, Paolicelli D (November 2001). "The differential diagnosis of multiple sclerosis: classification and clinical features of relapsing and progressive neurological syndromes". Neurol. Sci. 22 (Suppl 2): S98–102. doi:10.1007/s100720100044. PMID 11794488. http://link.springer-ny.com/link/service/journals/10072/bibs/122%20Suppl%202000/122%20Suppl%2020S98.htm. 
2. ^ ^{a b} McDonald WI, Compston A, Edan G, et al. (July 2001). "Recommended diagnostic criteria for multiple sclerosis: guidelines from the International Panel on the diagnosis of multiple sclerosis". Ann. Neurol. 50 (1): 121–7. doi:10.1002/ana.1032. PMID 11456302. 
3. ^ Polman CH, Reingold SC, Edan G, et al. (December 2005). "Diagnostic criteria for multiple sclerosis: 2005 revisions to the "McDonald Criteria"". Ann. Neurol. 58 (6): 840–6. doi:10.1002/ana.20703. PMID 16283615. 
4. ^ Link H, Huang YM (November 2006). "Oligoclonal bands in multiple sclerosis cerebrospinal fluid: an update on methodology and clinical usefulness". J. Neuroimmunol. 180 (1–2): 17–28. doi:10.1016/j.jneuroim.2006.07.006. PMID 16945427. 
5. ^ Gronseth GS, Ashman EJ (May 2000). "Practice parameter: the usefulness of evoked potentials in identifying clinically silent lesions in patients with suspected multiple sclerosis (an evidence-based review): Report of the Quality Standards Subcommittee of the American Academy of Neurology". Neurology 54 (9): 1720–5. PMID 10802774. http://www.neurology.org/cgi/pmidlookup?view=long&pmid=10802774. 
6. ^ SCHUMACKER GA, BEEBE G, KIBLER RF, KURLAND LT, KURTZKE JF, MCDOWELL F, NAGLER B, SIBLEY WA, TOURTELLOTTE WW, WILLMON TL. PROBLEMS OF EXPERIMENTAL TRIALS OF THERAPY IN MULTIPLE SCLEROSIS: REPORT BY THE PANEL ON THE EVALUATION OF EXPERIMENTAL TRIALS OF THERAPY IN MULTIPLE SCLEROSIS. Ann N Y Acad Sci. 1965 Mar 31;122:552–568.
7. ^ Paul O'Connor, James Marriott, Multiple Sclerosis, Chapter 2, Differential Diagnosis and Diagnostic Criteria for Multiple Sclerosis: Application and Pitfalls
8. ^ Poser CM, Brinar VV (June 2004). "Diagnostic criteria for multiple sclerosis: an historical review". Clin Neurol Neurosurg 106 (3): 147–58. doi:10.1016/j.clineuro.2004.02.004. PMID 15177763.