Weak evidence suggests that it may benefit patients with dysphagia associated with IBM (Asia–Pacific IVIg Advisory Board 2004). Description and Diagnostic Criteria The inflammatory myopathies are a group of three discrete disorders of skeletal muscle: DM, PM and IBM. These disorders are acquired and have in common the occurrence of significant muscle weakness and the presence of an inflammatory response within the muscle. The diagnosis of DM, PM or IBM is usually made by neurologists or rheumatologists, and relies on the combination of careful clinical evaluation, an elevated creatine kinase level, electromyography and muscle biopsy. IBM is an idiopathic inflammatory disorder of muscle. It is the most common inflammatory myopathy in individuals older than 50 years. Clinically IBM presents with slowly progressive weakness. It is more common in men than women (3:1). Along with proximal muscle weakness, distal muscles are commonly involved. The disease has a predilection for certain muscles, especially the quadriceps and long finger flexors, with prominent atrophy of the quadriceps muscle. Diagnostic criteria section has been revised and updated. SWG observed that IVIg in IBM continues to be controversial. Although initial trials looked promising, long term treatment does not appear justified. However there is an exception with regards to treating dysphagia which affects up to 70% IBM patients. This may even apply with the use of subcutaneous IVIg. (Muscle & nerve 2013;48(5):839-9. Diagnosis is required Diagnosis made by a neurologist, rheumatologist or immunologist Yes By which speciality Neurologist, rheumatologist or clinical immunologist Unchanged. Diagnosis must be verified No By which speciality Exclusion Criteria Expert consensus does not recommend IVIg to treat the limb weakness of IBM. IBM with limb weakness without dysphagia affecting function This exclusion criterion has been reworded for consistency with other exclusion criteria. Indications Patients with PM or DM with significant muscle weakness unresponsive to corticosteroids and other immunosuppressive agents. Patients with IBM who have dysphagia affecting function. Patients with IBM who have dysphagia limiting dietary intake Indication reworded to require biopsy confirmation and clearer definition of degree of dysphagia. SWG confirmed that there is no evidence that can be used to verify rapidly progressive IBM and noted that the criteria
Aim for the minimum dose to maintain optimal functional status. Dosing above 1 g/kg per day is contraindicated for some IVIg products. Refer to the current product information sheet for further information. The aim should be to use the lowest dose possible that achieves the appropriate clinical outcome for each patient. A maximum total dose of 1g/kg may be given in any four week period. This can be administered in weekly divided doses, provided total maximum is not exceeded. The aim should be to use the lowest dose possible that achieves the appropriate clinical outcome for each patient. Dosing above 1 g/kg per day is contraindicated for some IVIg products. Refer to the current product information sheet for further information. supported provided that the total maximum dose is not exceeded. BIBLIOGRAPHY