Please Silence Your Cell Phones. Thank You

Transcription

1 Please Silence Your Cell Phones Thank You

2 From Morphology to Molecular Genetics: Role of the Pathologist in Diagnosis of Muscle Disorders Karen M. Weidenheim, M.D. Department of Pathology (Neuropathology), Saul Korey Department of Neurology and Leo M. Davidoff Department of Neurosurgery Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY

3 Disclosure of Relevant Financial Relationships The USCAP requires that anyone in a position to influence or control the content of all CME activities disclose any relevant relationship(s) which they or their spouse/partner have, or have had within the past 12 months with a commercial interest(s) [or the products or services of a commercial interest] that relate to the content of this educational activity and create a conflict of interest. Complete disclosure information is maintained in the USCAP office and has been reviewed by the CME Advisory Committee. Dr. Weidenheim declares he/she has no conflict(s) of interest to disclose.

4 Muscle Biopsy 101 History Clinical considerations Technical considerations Methodology Basic pathology Uses for the paraffin block Importance of Histochemistry Special situations Muscle biopsy reports

5 Historical Background: 1960 s Gomori Trichrome stain modified for frozen sections of skeletal muscle Engel and Cunningham, 1963 Electron microscopy was an integral part of the diagnostic process, and still is EM used to confirm identity of structures noted on histochemistry Collaborative effort between neurologists and neuropathologists, neurochemists and pediatricians Role of MMC/AECOM Spiro, Gonatas 1990 s: Human genetics elucidated many of the disorders described in these early years Ongoing investigations still reveal new disorders

6 Relevance to 2015 What is the case mix on contemporary neuromuscular services? Difficult genetic myopathies Congenital myopathies Metabolic myopathies Glycogen storage disorders Lipid storage disorders Mitochondrial disorders Have CNS and cardiac manifestations as well as weakness: MERFF, MELAS Other unusual presentations such as MNGIE MyoNeurogenic GastroIntestinal Encephalopathy

7 Relevance to 2015 What is the case mix on contemporary neuromuscular services? Inflammatory myopathies Inclusion body myositis is always a consideration Infection related myopathies HIV1, HTLV1, Hepatitis B, C Complications of Diabetes Mellitus Diabetic (thigh) infarct Toxic myopathies, often related to therapeutic agents Statins: 11 million persons take them (2006) 7% get muscle aches and pains 0.5% get severe myopathy (10x elevated CK, pain, tenderness, weakness) Rhabdomyolysis may occur Statins may unmask previously subclinical conditions affecting muscle, esp. the metabolic myopathies of adulthood

8 Muscle Biopsy 101 History Clinical considerations Technical considerations Methodology Basic pathology Uses for the paraffin block Importance of Histochemistry Special situations Muscle biopsy reports

9 Before a biopsy is even considered: Careful history of the current complaint What other medical problems does this patient have? There may be manifestations of more than one disorder in the muscle, contributing to the weakness Diabetes Degenerative spine disease Careful analysis of the clinical laboratory data What was missed? Thyroid disease Diabetes mellitus

10 Before a biopsy is even considered: What drugs/supplements from the health food store/illegal substances does the patient use? What infections does the patient have or have they had in the past HIV 1, HTLV 1, hepatitis Was sarcoidosis cured in the past? Is there any suspicion of neoplasia? Could this be paraneoplastic, and should this possibility be worked up using clinical parameters?

11 Before a biopsy is even considered: Is there a family history of neuromuscular disease? Careful neuromuscular examination to answer the following: Is the complaint really localized to the peripheral nerves, skeletal muscle(s) or somewhere else? If this is indeed a neuromuscular issue, what is the differential diagnosis? Given the differential considerations, will a muscle biopsy be useful for diagnosis? If a muscle biopsy is indicated, which muscle is most likely to yield a diagnosis?

12 Role of Electrophysiology Electromyography Nerve Conduction Velocity Studies Helpful, with caveats Electrophysiology of myopathy, myopathy with inflammation and neurogenic change may overlap. Must not biopsy the muscle that was studied Otherwise, erroneous diagnosis of Myopathy with inflammation Assess the electrophysiology with skepticism

13 Reasons for performing a biopsy Clinical diagnosis Correct treatment Autoimmune therapy can be life threatening Prognosis of the patient How will the family cope with this disabled individual, often for months and years? Who will pay? Genetic counseling Prevention of more cases Muscle biopsy is an investment that pays off many fold in correct treatment of the patient, and proper counseling of the family

14 Muscle Biopsy 101 History Clinical considerations Technical considerations Methodology Basic pathology Uses for the paraffin block Importance of Histochemistry Special situations Muscle biopsy reports

15 Assembling the team Clinician(s) seeing the patient should understand the importance of neuromuscular examination prior to biopsy The surgeon: a thoughtful approach The anesthesiologist: aware of possible complications such as hyperthermia May occur in any muscle disorder Related to membrane instability Hypo and Hyperkalemia may also happen Inform Pathology at least 1 day ahead, to ensure availability of staff and reagents

16 The Hospital Operating Room willing to schedule early in the day Ensure the specimen reaches pathology during working hours when staff is available Issues with late in the day biopsies Willing to provide adequate technical assistance to the Pathologist who is responsible for the biopsy

17 Biopsy site The specimen Moderately involved muscle Not used for electrophysiology or injection of vaccine OR anesthetic Belly of the muscle Taken beneath the fascia Orientable 1 x 1 x 1 cm specimen Sent to lab fresh on salinemoistened Telfa Processed as soon as possible

18 Grossing the specimen Reagents Dry Ice Liquid nitrogen N methyl butane (isopentane) OCT embedding medium Formalin EM fixative of your choice Trump s solution Equipment 70 o ultrafreezer Dewar flask Stainless steel beaker (for the isopentane Cork blocks Long forceps (for freezing) Dental wax (for dissection) Dissection tools Storage boxes, foil, tubes etc

19 Specimens in order of importance Frozen Histochemistry Electron Microscopy Paraffin block For all ages Depending on patient age and differential dx Frozen muscle, not oriented, 350 mg, for possible biochemical/genetic analysis Unoriented trimmings can be used for the biochemical/genetic specimen Depending on differential dx

20 Muscle Biopsy 101 History Clinical considerations Technical considerations Methodology Basic pathology Uses for the paraffin block Importance of Histochemistry Special situations Muscle biopsy reports

21 Muscle biopsy set up Free of formalin/fixative/contamination Good lighting for good orientation

22 Dissecting the Specimen

23 Freezing the specimen

24 Freezing the Specimen

25 Dissecting the electron microscopy specimen

26 Histochemical staining battery Modified Gomori trichrome: basic analysis Differentiates the myofibrillar network from the remaining organelles Method of examining the subcellular structure of the muscle cell

27 Histochemical staining battery: 2 ATPase: Adenosine triphosphatase, at 3 ph levels: fiber typing stain NADH: Reduced nicotinamide adenine dinucleotide tetrazolium reductase PAS/PAS diastase for glycogen Phosphorylase: McArdle s disease (GSD V) 1/100,000 Increased risk for complications of statin therapy

28 Histochemical staining battery 3 Succinic acid dehydrogenase (SDH): mitochondria Cytochrome C oxidase (COX) Combined cytochrome C oxidase and succinate dehydrogenase Sudan black/oil Red O for lipid Myoadenylate deaminase Deficient in 1 2% of persons of European ancestry Acid phosphatase/alkaline phosphatase

29 Electron Microscopy is useful for Inclusion body myositis Mitochondrial disorders Congenital myopathies A congenital myopathy may present in adulthood Nemaline myopathy Metabolic myopathies Glycogen Lipid storage Myofibrillar myopathies

30 Muscle Biopsy 101 History Clinical considerations Technical considerations Methodology Basic pathology Uses for the paraffin block Importance of Histochemistry Special situations Muscle biopsy reports

31 Uses of the paraffin block Preliminary impression, with caveats Adequacy of the biopsy Issues of orientation Is this an end stage muscle? Pattern analysis on paraffin sections Myopathy Rule out Myopathy with Inflammation Very common reason for doing the bx Neurogenic versus type specific atrophy Need histochemistry Mixed myopathic and neurogenic picture Difficult; need histochemistry

32 Issue a Preliminary Report with great care Preliminary Reports may or may not be useful depending on the differential diagnosis, and the knowledge of the clinician If there is inflammation, preliminary results may allow treatment in the proper clinical setting The differential diagnosis of myopathy with inflammation includes but is not limited to autoimmune disorders, infections including HIV and HTLV 1, and heritable disorders muscular dystrophies. Clinical correlation is suggested. It is not possible to diagnose inclusion body myositis, which is steroid resistant, on paraffin sections Polymyositis is NOT a pathological diagnosis

33 Paraffin material & Preliminary Reports Other situations If ischemic, may indicate diabetic infarct of the muscle (no additional work needed) If perifascicular pattern with or without inflammation, diagnose dermatomyositis If there are minimal or no findings on the paraffin material, remember that the frozen histochemical blocks may be quite different due to focality of the disease process. It is helpful to so state in the Preliminary report The Preliminary Report should indicate what additional studies are in progress to obtain accurate final diagnosis

34 Paraffin looks may be deceiving Pitfalls in overall impression All muscle disease is focal Can miss inflammation, granulomas Even neurogenic changes are focal Protein coagulation Enhances angulation Be very careful of overdiagnosis of neurogenic change Not sensitive for showing degeneration/regeneration fibers in myopathies Paraffin will not show: Red rimmed vacuoles Ragged red fibers Nemaline rods Tubular aggregates Fiber typing issues Among other things Be careful Granulomas are easy to miss!

35 Muscle Biopsy 101 History Clinical considerations Technical considerations Methodology Basic pathology Uses for the paraffin block Importance of Histochemistry Special situations Muscle biopsy reports

36 Pattern Analysis: Neurogenic Atrophy Small angulated fibers Both fiber types affected Grouped atrophy Affected fibers have the same color as unaffected fibers Type grouping, indicating reinnervation after denervation, is confirmatory

37 Type specific atrophy may mimic neurogenic change It is not OK to stop with the H&E stain Type I smallness Type II atrophy

38 Pattern Analysis: Myopathy Random variation in size and shape Degeneration/regeneration Necrosis, phagocytosis +/ Inflammation? Inclusions

39 Myopathy with inflammation may not be an autoimmune disorder Gamma Sarcoglycanopathy HTLV 1/HIV1/Hepatitis

40 Inclusion Body Myositis Both autoimmune and degenerative changes Difficult to treat Diagnosed using clinical and pathological findings Red rimmed vacuoles Intrasarcoplasmic amyloid/tubulofilaments Protein accumulations: p62, TDP Partial invasion of non necrotic muscle fibers

41 Muscle Biopsy 101 History Clinical considerations Technical considerations Methodology Basic pathology Uses for the paraffin block Importance of Histochemistry Special situations Muscle biopsy reports

42 Dermatomyositis: Inflammation not required

43 Many faces of Dermatomyositis

44 Unremarkable Muscle can be deceiving

45 Normal muscle with type grouping: reinnervation after previous de nervation

46 Unremarkable Muscle or not?

47 It is not okay to not do the entire histochemical battery, unless you wish to miss diagnoses.

48 Diabetic infarct Painful mass in thigh of diabetic Clinical DDX: Infection Neoplasm Many clinicians are not aware of this entity May bleed when biopsied Try to diagnose clinically, not pathologically

49 Muscle Biopsy 101 History Clinical considerations Technical considerations Methodology Basic pathology Uses for the paraffin block Importance of Histochemistry Special situations Muscle biopsy reports

50 Muscle Biopsy Report Turn around time: variable Clinical correlation comment is fundamental to helping the patient Must understand the clinical considerations, as much as reasonable Put the histological findings, which may be nonspecific, into clinical context The clinical correlation comment should address the necessity for additional diagnostic procedures, as appropriate Confirmatory genetic testing

51 Take Home Points Muscle disease requiring biopsy is unusual, but not rare Pathologists should have a protocol in place for handling the biopsy should one occur at their institution Clinical information is essential for maximizing the information obtained from this painful procedure The Pathologist is a collaborating colleague who is critical for the care of these patients

52 Acknowledgements Dr. Patrick LaSala Dr. Steven Herskovitz and the Montefiore Neuromuscular Division Ms. Gloria Stephney Montefiore Pathology Cutting Room Staff Dr. Alfred Spiro THANK YOU VERY MUCH!

53 Important Information Regarding CME/SAMs The Online CME/Evaluations/SAM claim process will only be available on the USCAP website until October 2, No claims can be processed after that date! After October 2, 2015 you will NOT be able to obtain any CME or SAMs credits for attending this meeting.

54 Thank You! Please go to the USCAP website to complete your Evaluation of the course and claim CME and/or SAMs Credits.