1 / 35

Disclosure, Objective

Rational Use of Rheumatologic Lab Tests: aka “Choosing Wisely” Maryland ACP Scientific Meeting David B. Hellmann, M.D., M.A.C.P . Johns Hopkins Bayview January 31, 2014. Disclosure, Objective. Disclosure: none Objective:

sara-kent
Download Presentation

Disclosure, Objective

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Rational Use of Rheumatologic Lab Tests:aka “Choosing Wisely”Maryland ACP Scientific MeetingDavid B. Hellmann, M.D., M.A.C.P.Johns Hopkins BayviewJanuary 31, 2014

  2. Disclosure, Objective • Disclosure: none • Objective: • To use a case-based approached to discuss wise use of laboratory tests in rheumatic diseases • Methods—Accenting … • Choosing Wisely, Cases, and Differential Diagnosis

  3. Medical Professionalism in the New Millennium: A Physician Charter • Published simultaneously in 2002 in Annals of Internal Medicine, The Lancet and the European Journal of Internal Medicine • Charter articulated 3 principles • Primacy of the patient • Autonomy of the patient • Social justice • Includes aspiring to be good stewards of society’s resources

  4. Choosing Wisely: ACR Top 5 • Don’t test ANA sub-serologies without a positive ANA and clinical suspicion of immune-mediated disease. • Don’t test for Lyme disease as a cause of musculoskeletal symptoms without an exposure history and appropriate exam findings • Don’t perform MRI of peripheral joints to routinely monitor inflammatory arthritis

  5. Choosing Wisely: ACR Top 5 • Don’t prescribe biologics for rheumatoid arthritis before a trial of methotrexate (or other conventional non-biologic DMARDs) • Don’t routinely repeat DXA scans more often than once every two years

  6. AAFP Choosing Wisely • Don’t do imaging for low back pain within the first 6 weeks, unless red flags are present • Don’t use DEXA screening for osteoporosis in women < 65 or men < 70 with no risk factors.

  7. Case Presentation CC:42 y.o. man with acute LBP HPI:Moved office 48 hrs ago Awoke with acute LBP; worse with activity, better with rest. Naprosyn helps some. ROS: No fever, weakness, bowel/bladder sxs PMH: negative Examination: VS normal; tenderness LB; neuro exam (-) What tests should you order?

  8. Red Flags for LBP:AHRQ Criteria for X-ray for Acute LBP • Possible fracture • Major trauma, minor trauma > age 50 • Long-term corticosteroid use • Osteoporosis • Age > 70 • Possible Tumor or Infection • Age > 50, < 20 • History of cancer, injection drug use,recent bacterial infection, constitutional symptoms, immunosuppression • Pain when supine or at night

  9. Case Presentation CC: 78 y.o woman with headache HPI: 2 months fatigue, malaise, 5 lb weight loss 1 month of intermittent dull headache PMH: hypertension, osteoarthritis ROS: occasional jaw pain Medications: HCTZ, acetaminophen PE: 36.8 145/83 84 pale Labs: Hct 32, WBC 6,700 Platelets 532k CMP-nl ESR 105

  10. Erythrocyte Sedimentation Rate (ESR) • Ancient • Methods: Westergren, Wintrobe • Inexpensive • Uses: • Not diagnostic of any disease • Supports diagnosis of GCA, PMR, Osteomyelitis • Helpful in monitoring (GCA, PMR, RA, Osteomyelitis)

  11. Erythrocyte Sedimentation Rate

  12. Erythrocyte Sedimentation Rate (ESR) • Influenced by concentration of [asymmetric particles] = fibrinogen • Requires fresh sample • Normal values <20 mm • But affected by age (5/decade), gender, hematocrit, red cell morphology, many plasma proteins, medications (heparin)

  13. Giant Cell Arteritis:Accuracy of History, PE, LAB Symptom(+) LR(-) LR Jaw claudication 4.2 (2.8-6.2) 0.72 (.57-.81) Diplopia 3.4(1.3-8.6) 0.95 (.91-.99) Beaded TA 4.6 (1.1-18.4) 0.93 (.88-.99) Any TA abnl 2.0 (1.4-3) 0.53 (.38-.75) ESR abnl 1.1 (1-1.2) 0.2 (.08-.51) JAMA 2002;101:287-292

  14. Giant cell Arteritis with Low ESR Salvarani C, Hunder G. Arthritis Rheum 2001 N Total GCA patients (1950-1998) 167 # with ESR < 50 mm/hr 18 (11%) # with ESR < 40 mm/hr 9 (5%)

  15. ESR: Frequently Asked Questions • Can the ESR be normal in GCA? Yes • Does a ESR > 100 have special significance? Maybe • In an older person with >100 ESR and no obvious disease other than GCA, what else should I consider? Multiple Myeloma

  16. ESR Frequently Asked Questions 1. What gives false positives? Pregnancy, multiple myeloma, oral contraceptives, MGUS 2. What gives false negatives? Polymyositis. Cryoglobulinemia, congestive heart failure

  17. ESR: Frequently Asked Questions 1. Can the ESR be used as a screening test to determine if a patient with vague symptoms is sick? Not known! Only 31% of patients with gastric cancer have ESR > 20 2. What’s the maximum ESR a person can have? 200 – (2 x Hct) 3. Is CRP better than ESR?

  18. Case Presentation CC: 19 y.o. AA woman polyarthralgia, fever HPI: 5 wks polyarthralgia, fever, malar rash, pleuritic chest pain, nocturia, ankle swelling FH: Mother had SLE PMH: negative Meds: ibuprofen PE: T=37.9, malar erythema, alopecia, edema Labs: Hct 32, WBC 2.7 Platelets 110k Creatinine 1.2 Albumin 3.2, Urine 3+ protein, RBC casts, BC/RPR - What autoantibodies should you order?

  19. ANA: Commonly Asked Questions What is a positive ANA? 1-10% of well people have ANA >1:80 20 of “sick” people have ANA>1:80 What is value of ANA? negative ANA excludes SLE; no value monitoring What autoantibodies are specific for SLE? ds-DNA antibodies 99% specific; sensitivity 50% anti-SM specific (95%); sensitivity 30% low Complement: specificity ~90%, sensitivity 50%

  20. ANA Prevalence Disorder% (+) ANA SLE 99 RA 30-50 Fibromyalgia 20 Multiple Sclerosis 20 Thyroid disease 40

  21. Case Presentation CC: 24 y.o. woman with polyarthritis HPI: 5 wks polyarthritis mcps, pips, wrists, knees 2 hrs morning stiffness; fatigue ROS: (-) fever, weight loss, rash, weakness, chest pain, back pain, travel, tick exposure, neuropathy FH: negative Meds: naproxen PE: polyarthritis; no nodules Labs: Hct 35, ESR 58, CMP/UA negative What autoantibodies should you order?

  22. Rheumatoid Arthritis:Diagnostic Tests TESTSensitivitySpecificity RF 40-90% 40-90% Anti-CCP 70-80% 85-95% RF = rheumatoid factor Anti-CCP = anti-cyclic citrillinated peptide

  23. Differential Diagnosis Polyarthritis:If Host Is a 26 year old day care worker with faint, diffuse rash? Is a 55 year old smoker with new clubbing? Is a 49 year old with large joint arthritis and red eye? Is 34 year injection drug user with recurrent purpura?

  24. Case Presentation CC: 46 yo man oligoarthralgia, nasal stuffiness HPI: 3 months oligoarthralgia knees, shoulders nasal stuffiness, crusting, bleeding red eye, cough, fever, hearing loss left ear PMH: negative SH: no cocaine PE: scleritis, nasal crusting,otitis media, no joint effusion Labs: Hct 41, WBC 11k, Creatinine 1.6, urine 10-15 RBC’s; Chest CT: multiple nodules What autoantibodies should you order?

  25. ANCA Patterns and Associations PatternAntigenDisease C-ANCA proteinase-3 GPA P-ANCA myeloperoxidase MPA* Churg-Strauss Drug-induced GPA= granulomatosis with polyangiitis *MPA = microscopic polyangiitis

  26. Cocaine Induced Midline Destructive Lesions

  27. Levamisole Vasculitis

  28. Summary Choosing wisely is part of professionalism Avoid ordering imaging for acute LBP unless red flags are present Most blood tests in rheumatology should be ordered when the probability of disease is intermediate Don’t test ANA sub-serologies without a positive ANA and clinical suspicion

  29. CRP Levels < 1 mg/dl1-10 mg/dl>10 mg/dl Normal MI bacterial INF Pregnancy CTD vasculitis Depression Obesity Gingivitis

  30. ANCA Do IF first; confirm result with ELISA C-ANCA = anti-PR3 = GPA P-ANCA = anti-MPO = GPA, MPA etc “Atypical” ANCA = anti-Lactoferin, etc = IBD Cocaine, levamisole can cause vasculitis with positive C-ANCA, P-ANCA

  31. CRP vs ESR C-Reactive Protein (CRP) is an acute phase protein whose concentration reflects level of inflammation Unaffected by age (?), gender, monoclonal antibodies; fresh sample not required Quantification is precise; wide range of clinically relevant values May be more sensitive than ESR in GCA, PMR

  32. ANCA DiseaseSensitivitySpecificity GPA 70-90% 30-90%? MPA 70-90% 30-80% GPA= granulomatosis with polyangiitis *MPA = microscopic polyangiitis

  33. c-ANCA p-ANCA

More Related