L. Nandini Moorthy, MD MS 2012

Transcription

1 L. Nandini Moorthy, MD MS 2012

2 L Nandini Moorthy, MD MS yo Ashkenazi male with proximal muscle pain and weakness, mild malar erythema and erythema over knees and dorsal aspect of PIPs Mild tenderness over bilateral thighs and arms Unable to walk for a long time because of thigh pain History of sore throat one week prior to admission (admit date 2/17/09) No history of major physical exertion No history of supplement intake Elevated muscle enzymes (CPK ~94,000, Aldolase~3400; LDH 267; AST1033; ALT 445) ESR WNL Mycoplasma, ASLO, EBV, Influenza A and B, Hep panel -ve ANA and Jo-1 ab negative

3 L Nandini Moorthy, MD MS 09 Inflammatory polymyositis, dermatomyositis, inclusion body myositis, myositis with malignancy, myositis with another collagen vascular disease Neurogenic Toxic or drug related Infections viruses (coxsackie, influenza,, HIV), bacteria (staph, strep), Lyme disease, toxoplasmosis Neoplasm Genetic/Metabolic Miscellaneous Benign hyper CK emia

4 Any post exertional fatigue or cramping Unusual exertion in a poorly conditioned person Fasting Alcohol Medications (cocaine etc) Prior infection Pattern of weakness (calf pain versus thigh pain) Travel or eosinophilia (most relevant for localized myositis) L Nandini Moorthy, MD MS 09

5 L Nandini Moorthy, MD MS 09 Generalized proximal muscle weakness after a prodrome Work up and treat for rhabdomyolysis Work up towards a diagnosis Most likely diagnosis is viral myositis (influenza, enterovirus, EBV, HIV, Hep B and C etc) Likely +ve History of sore throat +ve No history of increased physical exertion/heat exposure +ve The very elevated muscle enzymes +ve/ ve Erythema over knees and dorsum of PIPS Less likely Absent calf pain

6 TThe cutaneous manifestations could be subtle and this could still be the early manifestation. CCutaneous manifestations (Heliotrope rash, Gottron s papules, periungual erythema) usually follow muscle symptoms L Nandini Moorthy, MD MS 09

7 L Nandini Moorthy, MD MS 09 Malaise, easy fatigue, muscle fatigue, fever & rash Insidious symmetric progressive proximal muscle weakness & pain Acute onset-1/3 >/=2 mo or longer prior to diagnosis Constitutional: Fever 38-40C, easily fatigued, anorexia, malaise, wt loss Milestone regression Could our patient have early-onset JDM? If the enzymes do not decrease, would consider steroids; would do an MRI and consider EMG and /biopsy

8 JDM

9 L Nandini Moorthy, MD MS 09 MSKS: symmetric proximal- weakness of LE limb girdle; anterior neck flexors/back & abdo Inability to hold head upright/maintain a sitting posture/stop walking/unable to dress/climb stairs/gowers Pelvic girdle- stairs, Trendelenburg- weak hip adductors Severe (10%) distal musculature unable to move pharyngeal, hypopharyngeal, palatal, esophageal hypomotility- difficulty swallowing, dysphonia, palatal speech, nasal regurgitation- threat of aspiration DTRs usually nl

10 Clinical features L Nandini Moorthy, MD MS 09 Photosensitivity Sun exposures- onset /exacerbation Oral ulcers - pain on swallowing Vasculitic- eye corners, axillae, pressure points, stretch marks Dystrophic calcifications-40% within 6 months of onset Early flexion contractures - muscle inflammation Persistent arthritis with myositis- THINK MCTD!

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17 Leukocytosis, anemia -rare unless GI bleed High CRP, ESR Microscopic hematuria IgA, IgG, IgE CPK, AST, Aldolase, LDH, ALT ANA ~10-85% MSA & MAA MRI T1-fibrosis, fat infiltration, atrophy T2-fat suppressed-edema/inflammation EMG Muscle biopsy L Nandini Moorthy, MD MS 09

18 Skeletal muscle perifascicular myopathy non-inflammatory capillaropathy disruption, degeneration, regeneration lymphocytic infiltrate -perimysium, perivascular L Nandini Moorthy, MD MS 09

19 L Nandini Moorthy, MD MS 09 Proximal muscle weakness Classic rash Elevated serum muscle enzymes Electromyographic changes Imaging Histopathology

20 Likely Elevated muscle enzymes Proximal muscle weakness Erythema over knees and PIPs (not classic Gottrens) Cutaneous signs are yet to appear? Less likely Muscle enzymes decreasing without any intervention Patient so well appearing Patient s weakness is not marked However the last two points are not really convincing!!!! L Nandini Moorthy, MD MS 2009

21 L Nandini Moorthy, MD MS 09 MRI of thigh (2/22/09): Showed patchy signal abnormalities involving bilateral thigh muscles most prominent in the adductor longus muscle most c/w myositis Cannot rule out Juvenile Dermatomyositis Although the muscle enzymes came down with hydration and time, they still remained elevated. Cannot rule out metabolic causes (in some cases can present in teens) Question: Post-infectious myositis versus JDM versus metabolic process? Answer: Follow the course

22 L Nandini Moorthy, MD MS 09 2/24/09: CPK 3412; AST 186; ALT 255 2/26/09: CPK 1502; Aldolase 40; AST 114; Ammonia 125 (27-102) Muscle enzymes still elevated Patient not doing GYM or other physical activities Questions remain: Post-viral myopathy versus Metabolic myopathy versus JDM (JDM lower on the list since enzymes are decreasing without any intervention) Could do EMG and /or Biopsy I decided to wait since the muscle enzymes were coming down, patient was feeling better and I wanted to consider another etiology

23 L Nandini Moorthy, MD MS 09 MSAs 40% of DM and PM patients Anti trna synthetase (Jo 1 in PM patients) antisynthetase syndrome myositis, interstitial lung disease, arthritis, Raynaud s phenomenon and hand skin lesions (mechanic s hand). Anti Mi 2 Acute onset, good prognosis; specific for DM Anti SRP Acute polymyositis with cardiac involvement, poor prognosis and poor response to therapy. MAA 20 50% of sera, encountered in connective tissue diseases PM/Scl nucleolar (overlap with Scleroderma) Anti Ku (overlap with other CTD) SnRNP (Small nuclear ribonuclear proteins) (overlap with other CTD) RoRNP (cytoplasmic ribonuclear proteins) (overlap with other CTD) All came back negative in our patient

24 L Nandini Moorthy, MD MS 09 Heterogeneous group of disorders Inability of skeletal muscle to produce or maintain adequate levels of energy (ATP Clinical features generally include: Fixed, progressive muscle weakness Premature fatigue Episodic aches, cramps and pains (Is this the first episode?) Occasionally extensive rhabdomyolysis with myoglobinuria Divided into: muscle glycogenoses disorders of lipid metabolism mitochondrial secondary myopathies (thyroid etc)

25 L Nandini Moorthy, MD MS 09 Many patients are asymptomatic Generally develop problems only when their level of activity or state of nutrition force their muscles to rely on the defective pathway; Episodes of weakness may be induced by fasting, unusual exercise intensity, intercurrent infection, alcohol consumption, general anesthesia or some medications In addition to proximal weakness, they may have elevated CK levels Myopathic changes on electromyography (EMG) and muscle Histology.

26 L Nandini Moorthy, MD MS 09 Neuro appointment at RWJMS Patient seen at the Neuromuscular center at CHOP Around that time(3/13/09), his muscle enzymes came down to normal (CPK 95; Aldolase 5.6; AST 21; ALT 27) (Ammonia 100) So the final opinion is viral myositis The slightly elevated recent Ammonia was it a false positive (I am always skeptical about outside labs)/ indicative of muscle fiber regeneration?

27 L Nandini Moorthy, MD MS 09 What if he has another episode? Would obtain EMG and a biopsy (expect myopathic changes) and send him to Neurology We minimized invasive testing (EMG and biopsy) We got an MRI no literature available on MRI findings in generalized viral myositis. Makes this case reportable!!!! Follow up is key!!!!