Schumacher criteria
Encyclopedia
Multiple sclerosis, understood as a CNS condition, can be difficult to diagnose
since its signs and symptoms may be similar to other medical problems. 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
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 band
s of IgG on electrophoresis, which are inflammation markers found in 75–85% of people with MS., 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 potential
s. 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 potential
s.
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).
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"
and McDonald criteria
.. 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.
Medical diagnosis
Medical diagnosis refers both to the process of attempting to determine or identify a possible disease or disorder , and to the opinion reached by this process...
since its signs and symptoms may be similar to other medical problems. 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
Sensitivity and specificity
Sensitivity and specificity are statistical measures of the performance of a binary classification test, also known in statistics as classification function. Sensitivity measures the proportion of actual positives which are correctly identified as such Sensitivity and specificity are statistical...
should be calculated for any given criteria
Context
Cerebrospinal fluid
Cerebrospinal fluid , Liquor cerebrospinalis, is a clear, colorless, bodily fluid, that occupies the subarachnoid space and the ventricular system around and inside the brain and spinal cord...
obtained from a lumbar puncture
Lumbar puncture
A lumbar puncture is a diagnostic and at times therapeutic procedure that is performed in order to collect a sample of cerebrospinal fluid for biochemical, microbiological, and cytological analysis, or very rarely as a treatment to relieve increased intracranial pressure.-Indications:The...
can provide evidence of chronic inflammation
Inflammation
Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...
of the central nervous system, looking for oligoclonal band
Oligoclonal band
Oligoclonal bands are bands of immunoglobulins that are seen when a patient's blood serum, gained from blood plasma, or cerebrospinal fluid is analyzed....
s of IgG on electrophoresis, which are inflammation markers found in 75–85% of people with MS., 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 potential
Evoked potential
An evoked potential is an electrical potential recorded from the nervous system of a human or other animal following presentation of a stimulus, as distinct from spontaneous potentials as detected by electroencephalography or electromyography .Evoked potential amplitudes tend to be low, ranging...
s. The nervous system of a person with MS responds less actively to stimulation of the optic nerve
Optic nerve
The optic nerve, also called cranial nerve 2, transmits visual information from the retina to the brain. Derived from the embryonic retinal ganglion cell, a diverticulum located in the diencephalon, the optic nerve doesn't regenerate after transection.-Anatomy:The optic nerve is the second of...
and sensory nerves
Sensory neuron
Sensory neurons are typically classified as the neurons responsible for converting external stimuli from the environment into internal stimuli. They are activated by sensory input , and send projections into the central nervous system that convey sensory information to the brain or spinal cord...
due to demyelination of such pathways. These brain responses can be examined using visual and sensory evoked potential
Evoked potential
An evoked potential is an electrical potential recorded from the nervous system of a human or other animal following presentation of a stimulus, as distinct from spontaneous potentials as detected by electroencephalography or electromyography .Evoked potential amplitudes tend to be low, ranging...
s.
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).
Summary
To get a diagnosis of CDMS a patient must show the following:- Clinical signs of a problem in the CNS
- Evidence of two or more areas of CNS involvement
- Evidence of white matter involvement
- One of these: Two or more relapses (each lasting ≥ 24 hr and separated by at least 1 month) or progression (slow or stepwise)
- Patient should be between 10 and 50 yr old at time of examination
- 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 criteriaPoser criteria
Poser criteria are diagnostic criteria for multiple sclerosis . They replaced the older Schumacker criteria, and now they are considered obsolete as McDonald criteria have superseded them...
and McDonald criteria
McDonald criteria
The McDonald criteria are diagnostic criteria for multiple sclerosis . These criteria are named after neurologist W. Ian McDonald. In April 2001 an international panel in association with the National Multiple Sclerosis Society of America recommended revised diagnostic criteria for MS...
.. Poser criteria introduced the CNS oligoclonal bands into the diagnosis criteria, while McDonald criteria
McDonald criteria
The McDonald criteria are diagnostic criteria for multiple sclerosis . These criteria are named after neurologist W. Ian McDonald. In April 2001 an international panel in association with the National Multiple Sclerosis Society of America recommended revised diagnostic criteria for MS...
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.