Week 3 Flashcards
A 40 yo woman comes to the hospital with the chief complaint of progressively worsening SOB. She reports that last winter, her fingers would turn purpelish blue after playing in the snow with her kids. Her SOB started around the same time and has been getting progressively worse. During review of systems, the physician also learns that the patient has felt irregular heart beats periodically during the past year and dysphagia of solids and liquids. The patient is found to be negative for anticentromere antibody, but positive for antitopoisomerase I anbibody. Which of the following is the most likely diagnosis for this patient?
- Systemic Lupus Erythematosus
- Diffuse Scleroderma
- Limited Scleroderma
- Sjogren’s Syndrome
- Rheumatoid Arthritis
Answer: 2. Diffuse Scleroderma
- Systemic Lupus Erythematosus – Can involve the lung (Pleuritis), heart (Libman-Sacks endocarditis), cause Reynaud’s Phenomenon (fingers turning white, blue, and then red in the cold), and be associated with dysphagia. However, more often associated with other ANAs, specifically anti-ds, anti0ss, antihistone, and anti-Sm.
- Diffuse Scleroderma – Often associated with Raynaud’s and involvement the lungs (interstitial fibrosis), heart (pericardial effusions and arrythmias), and GI tract (dysphagia and reflux). Visceral organ involvement usually occurs much later in diffuse scleroderma. In addition, antitopoisomerase I antibody is very specific for diffuse form. Also common in woman between the age of 35-50.
- Limited Scleroderma – Often associated with Raynaud’s phenomenon, but visceral involvement usually occurs much later. Anticentromere antibody is very specific for the limited form.
- Sjogren’s Syndrome – Common in women. Usually presents with dry eyes, dry mouth, arthralgias, and interstitial nephritis and vasculitis.
- Rheumatoid Arthritis – Usually presents with joint swelling, stiffness, and rheumatoid nodules on extensor surfaces. There can also be visceral organ involvement.
Lecture 242a: Describe the hallmark clinical features of SSc and current approaches to diagnosis and screening (MKS 1b, 1d)
A 50 yo woman presents to the hospital with dry eyes and dry mouth. She has no PMH of RA, system sclerosis, SLE, or polymyositis. Treatment with pilocarpine helps to relieve her dry eyes and mouth. This patient most likely has which syndrome? She has a higher risk for what type of malignancy? And which of the following findings is most likely in this patient? (Additional question to think about: why does pilocarpine relieve her symptoms?)
- Primary Sjogren Syndrome - Breast cancer – lymphocyte infiltration into lacrimal and salivary glands
- Secondary Sjogren Syndrome - Breast cancer – fibrosis of lacrimal and salivary glands
- Primary Sjogren Syndrome - Non-Hodgkin lymphoma - lymphocyte infiltration into lacrimal and salivary glands
- Secondary Sjogren Syndrome - Non-Hodgkin lymphoma - fibrosis of lacrimal and salivary glands
Answer: 3. Primary Sjogren Syndrome - Non-Hodgkin lymphoma - lymphocyte infiltration into lacrimal and salivary glands
Sjogren Syndrome is common in woman. It is caused by lymphocyte infiltration and destruction of lacrimal and salivary glands (other organs can be involved) resulting in dry eyes and mouth. If no other rheumatologic disease is present, the patient has primary Sjogren Syndrome. The presence of another rheumatologic disease would mean the patient has secondary Sjogren Syndrome. Patients with Sjogren Syndrome are have a higher risk of non-Hodgkin lymphoma and malignancy is the most common cause of death.
Pilocarpine is a muscarinic cholinergic agonist that increases salivation and lacrimation. It can also be used to treat closed angle glaucoma because it causes constriction of the pupils to increase space for draining of aqueous humors.
Lecture 238a: Describe aberrations in immune system function leading to autoimmunity and chronic inflammation (MKS1a)
A 30 yo woman presents to the hospital with swelling of her knees, proximal interphalangeal joints, and metacarpophalangeal joints bilaterally. She has lost 10lbs in the last year and experiences low-grade fevers not associated with a flu or cold. Her fingers are more stiff in the morning and feel better after use. Physical exam is most likely to reveal subcutaneous nodules found where? And antibody screening is likely to be positive of which of the following?
- Flexor Surface – Anti-dsDNA antibody
- Flexor Surface – Anticitrullinated peptide/protein antibody
- Extensor Surface – Anti-dsDNA antibody
- Extensor Surface - Anticitrullinated peptide/protein antibody
Answer: 4. Extensor Surface - Anticitrullinated peptide/protein antibody
This patient has Rheumatoid Arthritis. RA is more common in women and age of onset is between 20-40yo. It is an inflammatory autoimmune disease involving the synovium of the joints. Any joint in the body can be affected and constitution symptoms like fever and weight loss are often associated. Unilateral joint involvement, involvement of the DIP joints, and stiffness after use is more associated with OA. Subcutaneous rheumatoid nodules on extensor surfaces is pathoneumonic for RA. RA is associated with anticitrullinated peptide/protein antibody (ACPA) and rheumatoid factor (RF) – an antibody against Fc portion of IgGs).
Lecture 229a:
Differentiate between the symptoms, physical exam findings, and radiographic signs of RA vs osteoarthritis. (MKS1a)
List and interpret the typical laboratory findings in RA. (MKS1a)
A patient diagnosed with RA is treated with an appropriate disease modifying anti-rheumatic drug (DMARD). The patient begins to have frequent bouts of injections and experiences progressively worse SOB. She also complains of nausea and oral ulcers. The patient’s labs shows PT of 25 seconds. Supplementing with which of the following might improve the patient’s condition?
- Methotrexate
- Folate
- Etanercept
- Hydroxychloroquine
Answer: 2. Folate
This patient was most likely treated with methotrexate. Methotrexate is the first line DMARD for RA and takes 4-6 weeks to take effect. It is an immune suppressant that can also cause bone marrow suppression. Bone marrow suppression will lead to increased frequency of infections due to leukopenia, SOB due to anemia, and increased PT time due to thrombocytopenia. A folate supplement may help prevent bone marrow suppression. Methotrexate can also cause idiosyncratic interstitial pneumonitis (which can also cause SOB), liver damage (increased AST and ALT), GI upset, oral ulcers, and mild alopecia.
Etanercept is an antitumor necrosis factor that is also used to treat RA. It can cause reactivation of TB
Hydroxychloroquine is an alternative DMARD used for less severe RA cases. It can cause retinopathy.
Lecture 229a: Describe the goals for therapy in RA, common medications used, and the general approach to treatment(MKS1a)
A 50 yo man comes to the hospital complaining of a extreme pain in his big toe that woke him up in the middle of the night. On exam, the metatarsophalangeal joint seems erythematous, warm, swollen, and tender to touch. The patient has a PMH of HTN and taking Hydrochlorothiazide. After getting a joint aspiration, which of the following is mostly likely present in the aspirate?
- Needle-shaped and negatively birefringent crystals
- Rod-shaped and weakly positively birefringent crystals
- WBCs and RF
- No abnormalities
Answer: 1. Needle-shaped and negatively birefringent crystals
Acute pain in the big toe in a man between the age of 40-60yo is most likely to be gout. Uric acid crystals are needle-shaped and negatively birefingent. The use of thiazides can increase urate reabsorption in the proximal tubules of the kidneys directly and indirectly (loss of volume causes kidneys to retain more solutes to preserve volume).
Rod-shaped and weakly positively birefringent crystals are from Pseudogout which more often affect weight bearing joints in older men.
WBCs and RF maybe found in a patient with RA, which would more often affect the PIP and MCP of the hands instead of the big toe
No changes maybe seen in a patient with OA.
Lecture 239a:
List crystals that cause arthropathy/arthritis (MKS 3b)
Describe the typical clinical picture for crystalline arthropathies (MKS 3b)
A 70 yo man comes to the hospital complaining of pain in his right knee. He has a PMH of osteoarthritis and have had pain in his right knee previously. A joint aspirate shows weakly positive birefingent, rod-shaped and rhomboidal crystals. Which of the following are the crystals most likely to consist of?
- Uric acid
- Calcium pyrophosphate
- Dead WBCs
- Hemoglobin deposits
Answer: 2. Calcium Pyrophosphate
Pseudogout most likely occurs in elderly patients with degenerative joint diseases like OA. The most common presentation is monoarticular pain in knees or writs. Pseudogout is caused by deposition of calcium pyrophosphate in the joints and causing inflammation.
Uric acid deposition occurs in gout, which would lead to a different clinical picture. Dead WBCs and hemoglobin deposits would not lead to the clinical picture seen in the case.
Lecture 239a:
List crystals that cause arthropathy/arthritis (MKS 3b)
Describe the typical clinical picture for crystalline arthropathies (MKS 3b)
A patient comes to the hospital complaining of difficulty moving his right hand after falling off of a rock climbing wall. When asked to make a fist with his write hand, he is unable to wrap his thumb around his fingers. The thumb remains extended and adducted. There is also ulnar deviation of his wrist. When asked to flex his fingers, the patient is unable to flex his second and third digits. The patient has loss of sensation to the radial side of his palm and to his second and third digits. Which of the following is the most likely to cause these findings?
- Epicondyle fracture leading to severance of the ulnar nerve
- Fracture of the hook of hamate leading to severance of the ulnar nerve
- Supracondylar fracture leading to severance of the median nerve
- Swelling of the finger flexor tendons in the carpal tunnel leading to compression of the median nerve
Answer: 3. Supracondylar fracture leading to severance of the median nerve
- Would lead to a proximal median nerve injury. Both proximal and distal median nerve injury leads to ape hand (thumb remains extended and adducted when making a fist), and loss of sensation to the radial side of the palm and the second and third digits. A proximal injury will result in Pope’s blessing (unable to flex second and third digit) when the patient tries to flex his fingers.
- A distal lesion of the median nerve will cause median claw (MCP extended and IP joints flexed because of loss of lumbricals) at rest. Flexion of the second and third digit would still be intact. The median claw is caused by loss of the first and second lumbricals, which help to flex the MCP and extend the IP joints.
- Would lead to a proximal ulnar nerve injury. Both proximal and distal ulnar nerve injury would cause loss of thumb adduction and loss of sensation to the fourth and fifth digits and the ulnar side of the hand. A proximal lesion would cause mild ulnar claw at rest (fourth and fifth digits slightly flexed)
- Would lead to distal ulnar nerve injury which would cause ulnar claw when the patient tries to extend hist fingers (fourth and fifth digits remain flexed and can look like the Pope’s blessing). Here the loss of the 3rd and 4th lumbricals prevent flexion of the MCP joints and extension of the IP joints.
Lecture 237a:
List the causes and effects of injury to the nerves of the upper limb (MKS1a).
An action potential from a motor neuron causes depolarization of the muscle cell membrane and opens L-type Ca channels. The L-type Ca channels then couple with ryanodine receptors to cause Ca release from what structure in order to initiate muscle contraction?
- Rough Endoplasmic reticulum
- Smooth Endoplasmic reticulum
- Sarcoplasmic reticulum
- Mitochondria
Answer: 3. Sarcoplasmic reticulum
Calcium is released from the sarcoplasmic reticulum in order to begin contraction.
Lecture 236a: Define how the molecular properties of muscle produce function effects for movement (MSK 1a)
Describe basic mechanical properties of our musculoskeleltal system, especially its springlike behavior (MSK 1a)
