Therapeutic Areas and Products
Our world-leading immunoglobulin (Ig) franchise includes an intravenous and a subcutaneous option and is the cornerstone of the neurology therapeutic area. Our efforts in this area focus on bringing trusted products and technologies to serve patients with a rare and serious neurologic disease, Chronic Inflammatory Demyelinating Polyneuropathy (CIDP).
CIDP Diagnostic Tools
The Inflammatory Neuropathy Cause And Treatment (INCAT) disability score was developed in 2001 and used for the first time in a clinical study comparing the efficacy and safety of intravenous immunoglobulin with oral prednisone in patients with CIDP. It has subsequently been used in several CIDP clinical trials, although its use in day-to-day clinical practice is uncommon.
The INCAT comprises two parts, the arm score and the leg score. Based on a patient’s level of impairment in their arms and legs, each part is scored between 0 and 5 points, resulting in an INCAT total score between 0 and 10. The adjusted INCAT score, which is used in clinical trials, excludes changes of 0 to 1 or 1 to 0 in upper limb function as regulatory agencies do not considered this clinically significant.
Note: INCAT score is inversely related to function, with 0 representing no functional impairment and 10 representing inability to make any purposeful movement with either arms or legs.
The Inflammatory Rasch-built Overall Disability Scale (I-RODS) was developed in 2011 and is intended to specifically assess activity and social participation limitations in patients with inflammatory neuropathies. It is a patient-reported outcome measure, meaning the assessment is dependent on a patient’s own assessment about his or her disability.
I-RODS is a 24-item scale, with each item representing a common, daily activity. I-RODS captures clinically meaningful changes over time and is scored from 0-100 (0 is the most severe limitation in activities and social participation, 100 is no limitation in activities and social participation).
The items range in difficulty from very easy (“reading a newspaper/book” and “eating”) to very difficult (“standing for hours” and “running”) The patient assigns a score between 0 and 2 to each item as follows:
- 0 = impossible to perform
- 1 = performed with difficulty
- 2 = easily performed
MRC Sum Score
The Medical Research Council (MRC) system for testing and grading of muscle function aims to provide a standardized and objective way to assess muscle function.
It was originally introduced in 1943 and has a long history of use in neurology, rehabilitation and general medicine examinations.
In the MRC grading system, each tested muscle is assigned one of the following scores based on its function. Scores range from 0-80; 0 being paralysis and 80 being normal strength.
- 0 = paralysis
- 1 = only a trace or flicker of muscle contraction
- 2 = muscle movement is possible with gravity eliminated
- 3 = muscle movement is possible against gravity
- 4 = muscle strength is reduced, but movement against resistance is possible
- 5 = normal strength
Assessments of muscles are done bilaterally, meaning that for each muscle tested, the same muscle on the opposite side of the body is also tested. The MRC sum score is finally calculated by adding the score of each individually assessed muscle.
Grip strength assessments have been recommended to be used in clinical practice because they can be done with relatively simple tools and provide near instantaneous results.
A variety of tools are available to assess grip strength; two commonly used instruments are the Martin Vigorimeter and Jamar Dynamometer.
With the Martin Vigorimeter, the patient squeezes a rubber ball that is connected to a manometer with rubber tubing.
- The patient’s grip strength is expressed in kilopascal (kPa), with a range of0–160 kPa
With the Jamar Dynamometer, the patient squeezes the handle of a hand-held device inwards against increasing resistance.
- The patient’s grip strength is expressed in kg or lb, with a range of 0–90 kg or 0–200 lb
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