Progressive Weakness

 Chief Complaint: A 46 year-old female presents with 3 months of progressive weakness.

DOMAIN A: DATA ACQUISITION

+ What are the key components of this patient’s history and physical examination, and why?

Relevant History:

  • How did this begin? Onset of symptoms?
  • Please describe the weakness. Where exactly does she feel weak? What functional tasks or activities of daily living (ADLs) does she have difficulty performing?
  • Was there injury/trauma?
  • Is there pain? If so, where exactly is the pain? Quality, duration, aggravating/alleviating factors, radiation?
  • Has this ever happened before?
  • Is there stiffness, fever, rash, gait dysfunction, dysphagia, numbness, or tingling?
  • Any bowel or bladder deficits?
  • What has she tried so far to alleviate the problem? Medications, therapy, bracing, injections, surgery?
  • Has she had any workup already for this problem?
  • Is she typically physically active?
  • What is her work history and current working status?
  • Functional history and current functional status?
  • Family history?
  • Past Medical and Surgical History?
  • Medications?

Relevant Physical Examination:

  • Vital signs
  • Inspection
  • Palpation
  • Gait observation
  • Skin, heart, lungs examination
  • Manual muscle testing of bilateral upper and lower extremities
  • Sensory and reflex testing of bilateral upper and lower extremities
  • Special testing: As directed by history. Consider Spurling, Straight leg raise, Tinel.
 

DOMAIN B: PROBLEM SOLVING

The patient’s symptoms began gradually over the past few months without trauma. She has no significant past medical history other than hypertension and hyperlipidemia for which she takes lisinopril and atorvastatin. She is functionally independent. She notes progressive weakness most noticeable when climbing the stairs or carrying bags of soil while gardening. She denies numbness, tingling, or bowel or bladder deficits. Her muscles feel sore especially towards the end of the day, even if she has not exercised. On examination, her vital signs are normal. She exhibits marked difficulty when rising from a chair. She is tender to palpation over her bilateral thighs. Manual muscle testing reveals 4/5 strength in bilateral shoulder flexion and abduction, bilateral hip flexion and knee extension, and 5/5 distally in the upper and lower extremities.

+ What is your differential diagnosis for this patient?

  • Polymyositis (PM), dermatomyositis (DM), inclusion body myositis (IBM), Lambert-Eaton Myasthenic Syndrome (LEMS), Myasthenia Gravis (MG), statin myopathy, Guillain-Barre Syndrome (GBS/AIDP), CIDP, systemic lupus erythematosus (SLE), cervical myelopathy, polymyalgia rheumatica (PMR).
 

DOMAIN C: PATIENT MANAGEMENT

+ What would be your next steps in managing this patient?

  • I would start physical therapy for functional rehabilitation, as this patient is having difficulty performing ADLs and I want to ensure she can maintain independence. I also need to reach a diagnosis in her so we can tailor her treatment appropriately. Thus, I would like to order some labs and an EMG/nerve conduction study to start.
 

+ What specific labs would you order?

  • I would order a complete blood count (CBC), CK, ESR, CRP, AST/ALT, aldolase, and LDH. I would consider adding ANA, anti-smith antibodies, and anti-Jo-1 antibodies depending on these results.

+ EMG returns, showing evidence of a myopathic process. Describe the findings of myopathy on EMG.

  • Increased insertional activity, possibly fibrillations. Early recruitment of short-duration, small-amplitude motor unit action potentials (SDSA MUAPs). May see presence of complex repetitive discharges (CRDs).

+ Laboratory studies reveal the following:

  • CBC: normal
  • CK: elevated
  • ESR: elevated
  • CRP: elevated
  • Aldolase: elevated
  • LDH: elevated
  • AST/ALT: elevated
 

DOMAIN D: SYSTEMS-BASED PRACTICE

+ You receive these results, but your patient is not able to get in to see you in follow-up for another 3 months. What is your next step?

  • I would either add her onto my schedule in an extra patient slot in the very near future, or would call her personally and discuss her test results and next steps.
 

+ The patient does not want to come into the office but wants direction on what to do next. What is your next step?

I would call her, verify her identifying information, and explain the test results and next steps which should be a referral to a neuromuscular specialist or rheumatologist. I would also recommend getting a muscle biopsy.

 

+ Muscle biopsy of the quadriceps (the side not studied on EMG) reveals the following:

  • Inflammatory cell load within muscle fibers.
  • Perifascicular atrophy.
 

DOMAIN E: INTERPERSONAL AND COMMUNICATION SKILLS

This is the role-playing portion of this case. Pretend that I am the patient.

+ Doctor, what does this all mean? I don’t understand why I am so weak and getting all these tests without answers.

  • I would be happy to discuss this with you. Based on your pattern of weakness, laboratory tests, EMG, and muscle biopsy, I am concerned that you are suffering from a condition that causes muscle inflammation and weakness, specifically a condition called polymyositis. Essentially, inflammation enters the muscles due to an unknown cause, and this can cause significant muscle weakness as a result.

+ What can we do to fix it?

  • Unfortunately we will likely not be able to completely cure the condition, but we have treatments available that can manage it for you. It starts with physical therapy to help maintain your function and independence so you can keep doing the activities that you enjoy doing without assistance. We also need to treat the inflammation so your strength can improve. This is done by using medicine called steroids (corticosteroids/glucocorticoids), and possibly more specific medications for your immune system as well. That is where the guidance of a rheumatologist or neuromuscular specialist will help us.

+ Are there side effects of using steroids like this? What should I worry about?

  • Yes. Longterm steroid usage can cause a condition called osteoporosis, which is essentially bones that are not as strong as normal. This is why it’s important to order a bone scan for you called a DEXA scan, which can measure your bone density levels prior to starting these steroids. I would also ask you to consult with an endocrinologist for recommendations on how to limit bone loss during this period of steroid usage. I will personally notify all the physicians involved in your care so that everyone is on the same page and up to date with our management. These are excellent questions you ask. What other questions do you have for me today?