muscle disease

Question 1

polymyositis causes

Answer 1

statins can cause muscle pain/muscle necrosis

Question 2

polymyositis pathophysiology

Answer 2

• cell mediated autoimmune disorder in which CD8, cytotoxic lymphocytes and macrophages invade and destroy myofibers expressing MHC-1 antigens
• inflammatory cells found in the endomysium (between and around myofibers)

Question 3

dermatomyositis cause

Answer 3

statins can cause muscle pain/muscle necrosis

Question 4

dermatomyositis pathophysiology

Answer 4

• inflammation, vasculitis and perifascicular necrosis
• inflammatory cells (main B cells, with small numbers of CD4 and T cells) that are found around blood vessels, septa between muscles fascicles and in fibroadipose tissue around muscle

Question 5

dermatomyositis skin manifestations

Answer 5

• Gottron’s sign (scaly, round and pink papules over the knuckles)
• heliotrope rash (lilac around the eyes)
• shawl sign (macular rash over back and shoulders)

Question 6

polymositis and dermatomyositis presentation

Answer 6

• slow onset of symmetrical, proximal muscle weakness
• mild myalgia
• interstitial lung disease
• dysphagia
• myocarditis
• fever
• weight loss
• Raynaud’s
• polyarthritis
• reduced muscle
• power on confrontational and isotonic testing

Question 7

polymyositis and dermatomyositis diagnosis

Answer 7

• elevated creatine kinase and inflammatory markers
• anti-jo 1
• electromyography showing increased fibrillations, abnormal motor complexes and complex repetitive discharges
• biopsy showing perivascular inflammation and muscle necrosis

Question 8

polymyositis and dermatomyositis management

Answer 8

• malignancy screening
• may need IV immunoglobulin
• steroids and DMARDs

Question 9

what is inclusion body myositis

Answer 9

inflammatory muscle disease that primarily presents with muscle weakness

Question 10

inclusion body myositis is most common in

Answer 10

men > 50

Question 11

inclusion body myositis presentation

Answer 11

• weakness weakness tends to be asymmetrical and can affect distal or proximal muscle groups
• biopsy for inclusion bodies
• creatinine kinase elevated but not as high as polymyositis
• respond poorly to treatment

Question 12

polymyalgia rheumatica is most common in

Answer 12

women > 50

Question 13

polymyalgia rheumatica presentation

Answer 13

• myalgia and stiffness with onset being over a few weeks
• fatigue, fever, weight loss and depression
• morning stiffness lasting > 1 hour
• distribution mainly over shoulder and pelvic region
• reduction in active but not passive movements

Question 14

giant cell arteritis presentation

Answer 14

• unilateral headache
• scalp tenderness (sore to brush hair)
• temporomandibular joint claudication
• tongue claudication
• tender, enlarged, non-pulsatile temporal artery
• amaurosis fugax
• diplopia

Question 15

polymyalgia rheumatica diagnosis

Answer 15

• raised inflammatory markers and creatinine kinase normal
• temporal artery ultrasound
• temporal artery biopsy or MRI

Question 16

polymyalgia rheumatica management

Answer 16

• 15 mg oral prednisolone
• 40-60 mg oral prednisolone if giant cell arteritis and continue for 18 months