The disease includes degenerative changes of the muscle tissue, primarily either the wrists or the thighs. The symptoms can be noticed by the patients when they complain of loss of grip either while walking, wearing footwear, lifting their feet or in the case of the upper extremity when holding a bag or lifting a suitcase and gripping objects which may lead to many accidental drops or slipping and falling.
70% of the patients usually experience similar symptoms involving the use of extremities. 30 to 35% patients have involvement of other muscle tissues like that of the oesophagus that leads to difficulty in swallowing. Specifically in inclusion body myositis, the other muscle tissues like cardiac muscle or skin and lungs are generally not involved unlike other myopathies.
- History of frequent falls
- Difficulty in getting up from a chair or from standing after lying down
- Clumsiness while walking, tripping often or loss of footing
- Awkwardness with the upper extremities – dropping of things from hands due to a weak grip
- Difficulty while swallowing
Symptoms that can be observed:
- Visible shrinking of the quadriceps due to atrophy
- Muscle power grade weakened in the forearm
- Muscle power grade decreased below the knees
- Muscle power and contraction difficult around the MCP joints and weaker grip on pinching and squeezing with fingers noted during examination
Entire Body System
Many patients say they have balance problems and fall easily, as the muscles cannot compensate for an off-balanced posture. [en.wikipedia.org]
Patients were reported to have experienced dysphagia (60.2%) and injurious falls (44.3%) during their disease. [ncbi.nlm.nih.gov]
Exercise and Myositis Fall Prevention Frequent unexplained falls are often a reason people seek medical attention. Remember, one fall is too many. Fall prevention is an important factor in staying safe with inclusion body myositis. [understandingmyositis.org]
- Excessive Daytime Sleepiness
Four reported excessive daytime sleepiness; 8 had at least mild dysphagia; forced vital capacity was Copyright 2014 Elsevier B.V. All rights reserved. [ncbi.nlm.nih.gov]
In this study, DNA from 79 patients with sIBM was collected and the sequencing of 38 genes associated with hereditary inclusion body myopathy (IBM), myofibrillar myopathy, Emery-Dreifuss muscular dystrophy, distal myopathy, amyotrophic lateral sclerosis [ncbi.nlm.nih.gov]
Brain 128 : 1887–1896 61 Dalakas MC (2003) Therapeutic approaches in patients with inflammatory myopathies. [doi.org]
- Muscle Weakness
We have identified several patients with sIBM in our cohort with muscle weakness of the flexors but not the quadriceps femoris. [ncbi.nlm.nih.gov]
The onset of muscle weakness in IBM is generally gradual (over months or years) and affects both proximal (close to the trunk of the body) and distal (further away from the trunk) muscles. Muscle weakness may affect only one side of the body. [ninds.nih.gov]
The unexpected appearance of myalgia during the course of painless inclusion body myositis must arouse the suspicion of an association of another inflammatory muscle disease, macrophagic myofasciitis. [ncbi.nlm.nih.gov]
Myalgia and muscle tenderness may occur in a small number of patients, usually early in the disease, and particularly in DM associated with connective tissue disorders. [accessmedicine.mhmedical.com]
Case 1 A 63-year-old woman presented with a 4-year history of myalgia related to statin therapy. Myalgia persisted more than 1 year after statin discontinuation in 2010. [karger.com]
[…] a greater extent than the dominant side The most common complaint is quadriceps weakness Finger flexor and ankle dorsiflexion weakness can be noted clinically Dysphagia is a common symptom ( J Neurol 2005;252:1448 ) Generally, patients do not report myalgias [pathologyoutlines.com]
- Leg Weakness
leg weakness, L hand weakness, b/l arm weakness SA 4, FF 4 , HF 3, HA 4, KF 4 , DF 4 , KE 4 Myopathic Atrophic myofibers, minimal endomysial inflammation, rimmed vacuoles Unknown 16 71 120 F Leg weakness, then hand weakness, then difficulty swallowing [jmedicalcasereports.biomedcentral.com]
One (patient 7) had mild proximal leg weakness without wasting. All 5 patients with leg weakness at onset had weakness of the quadriceps. [jamanetwork.com]
On examination, he was not ambulatory with marked symmetrical proximal arm and leg weakness. Labs including CBC, CMP, ANA, ESR, CRP, and TSH were normal. Serum creatine kinase was 6,500. [n.neurology.org]
Lower leg weakness can cause difficulty lifting up the foot, which can lead to tripping. [encyclopedia.com]
- Proximal Muscle Weakness
We report a 17-year-old girl with an unusual neuromuscular disorder characterised by slowly progressive proximal muscle weakness whose muscle biopsy showed multiple ring fibres and numerous rimmed vacuoles as well as intracytoplasmic and intranuclear [ncbi.nlm.nih.gov]
Key Points • Proximal muscle weakness • May have characteristic skin involvement • • Heliotrope eyelids Gottron’s sign Polymyositis/Dermatomyositis • Diagnosis confirmed by CK levels EMG findings Muscle biopsy • • • Polymyositis/Dermatomyositis (cont [studocu.com]
IBM inclusion body myositis, NHL non-Hodgkin’s lymphoma Our patient was not receiving any drugs associated with muscle injury, but 5 years after developing non-Hodgkin’s lymphoma, gradual-onset proximal muscle weakness was noted in his legs. [jmedicalcasereports.com]
Apart from the physical examination and findings mentioned above, a haemogram would reveal nothing that is diagnostic in value.
Serum Alkaline Phosphatase levels will be significantly raised.
Serum creatine kinase will be low – as low as 12 times below normal.
EMG studies – electromyography would show all the known features of myopathy – inflammatory or non-inflammatory based on the type of Inclusion Body Myositis or Inclusion Body Myopathy.
A muscle biopsy would follow an electromyography to confirm the diagnosis and look for the ‘bodies’ – clusters of degenerated cells. Also, visible would be the invasion of mono nuclear cells in the non-necrotic fibres and vacuolated muscle fibres.
In terms of treatment, more than what works, one can be sure of what doesn’t. Based on many reports in the past and clinical studies – steroids, methotrexate, azathioprine and cyclophospamide don’t elicit favourable response from the patients. Similarly immunosuppressive and immunomodulatory therapies are also a failure .
Some empirical therapies that may cause some relief or palliation to the patients are Coenzyme Q10, carnitine and anti-oxidants, although unfortunately these are not supported by clinical trials.
Follow up criteria for such patients  is the assessment of the pace and progression of the degenerative changes and to note the severity of muscle tissue damage via physical examination assessing the muscle power in terms of strength, stamina and any subsequent problems or difficulties in daily routine activities.
The prognosis for Inclusion Body Myositis is bleak but the only bright side is its slow progression and the fact that most of the times it begins after 50. With some luck most patients having the condition are able to walk with assistance while some may find themselves wheelchair ridden. Another aspect is that the disease is limited to the upper extremities or the muscle tissue it affects is not life threatening .
While the cause for Inclusion Body Myositis or even myopathy is not very clear, what is known is that it is an autoimmune disorder. The body attacks its own muscle tissue and in the process damages it causing degenerative changes, the exact mechanism of which is not very clear at the moment.
Even though it cannot be pinpointed to one cause, it is clear that there exists a genetic involvement. That gene can be either dominant or recessive, probably linked more to males.
Drug side-effect involvement has not been ruled out in cases of inclusion body myositis. There are a few drugs that are known to be trigger factors but are pending research e.g. caricaine, carbimazole, cimetidine, penicillamine and phenytoin .
Males have found to be suffering from Inclusion Body Myositis 2 times more than women. The onset of symptoms is usually seen after the age of 50 years but sometimes the symptoms manifest after the 3rd decade of life as well. These symptoms are subtle signs of weakness in the muscles, like the atrophy of the muscles of the forearm or thighs. The same muscular weakness may be seen in the wrist or fingers and occasionally, as dysphagia owing to the weakness of the musculature of the oesophagus .
The pathophysiology of Inclusion Body Myositis involves both inflammatory as well as degenerative characteristics even though it is known to be similar to other myopathies like dermatomyositis and polymyositis. Though the exact pathogenesis is not clearly known, there are 3 main theories regarding it. One of which is that since it is an auto-immune disorder, there is a primary T-cell mediated response, which is an autoimmune reaction and this causes the muscle damage.
Another theory proposes that the degenerative process is the primary reaction and owing to some protein causes an inflammatory response as the secondary reaction. There is one more theory which claims that both the immune response degenerative changes are two separate reactions and independent of each other which maybe triggered by some external factor.
Being a genetically inherited mutation, there is no prevention available for the condition.
Inclusion Body Myositis (IBM) is the term used to signify a disorder caused due to inflammation of muscles. Its characteristic feature is progressive muscle weakness and wasting. It is a type of myopathy and can affect the blood vessels surrounding the muscles as well. Literal translation will tell us that it means inflammation of the root of the muscle.
One of the characteristics of Inclusion Body Myositis is that the muscle tissue is invaded by a number of inflammatory cells that bring along with it muscle degeneration. Later one can find ‘the bodies’ – that is the waste cells or deceased cells that collect in the tissues of the muscles.
Some rare forms of Inclusion Body Myositis which are genetic or hereditary in nature can present the same symptoms as regular IBM except for the inflammation. In such cases, since there is no inflammation the suffix ‘itis’ is not used and the nomenclature changes to myopathy – inclusion body myopathy – to signify the muscle disorder without the inflammation.
Inclusion Body Myositis is generally a hereditary disorder passed on more in men than women and is usually noticed only after 50 years of age. It is a disease which involves the muscle tissue but is specific only to the muscles of the wrists, upper extremities or of the legs, especially of the thighs. Occasionally it may also involve the muscle of the oesophagus.
As a result of this the symptoms noticed by you may involve dropping things, loosing grip, difficulty in holding objects or if your lower limbs are affected then tripping, falling, loss of footing, difficulty in raising your leg or getting up from a seated position.
Sometimes it may also be caused as a reaction to viruses like the HIV and Coxsackie B. It is essentially an auto-immune disorder, which means, the body cells attack their own muscle tissue. The cause of this is not well understood as is the treatment – another hazy area.
Medicines like CoQ10, carnitine and anti-oxidants may provide some relief. Good news, in a way, is that it is not fatal and has a very slow pace of progression and limits itself to these few areas, not affecting the heart or lungs like other myopathies.
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- Cox FM, Titulaer MJ, Sont JK, Wintzen AR, et al. A 12-year follow-up in sporadic inclusion body myositis: an end stage with major disabilities. Brain. Nov 2011;134:3167-75
- Lotz BP, Engel AG, Nishino H, et al. Inclusion body myositis. Observations in 40 patients. Brain. Jun 1989;112 (Pt 3):727-47
- Breithaupt M, Schmidt J. Update on treatment of inclusion body myositis. Curr Rheumatol Rep. May 2013;15(5):329.
- Hicks J. Comprehensive rehabilitative management of patients with polymyositis and dermatomyositis. In: Dalakas M, ed. Polymyositis and Dermatomyositis. Boston, Mass: Butterworth-Heinemann; 1988:293-318.