Show Notes
4.11 Antibody Review Rheumatology review for the USMLE Step 1 Exam. ANA Principles ANA (Anti-Nuclear Antibody): Non-specific antibody. Reacts against nuclear antigens, including proteins, DNA, RNA, and nucleic acid-protein complexes. Includes a group of antibodies such as anti-dsDNA, anti-histone, SSA/Ro, SSB/La, Scl-70, anti-aminoacyl-tRNA synthetase (Jo-1). Found in 20-30% of the general public without connective tissue disorder symptoms.
ANA+ individuals may or may not have a rheumatologic disorder. Further workup is needed in ANA+ cases to determine the specific disorder. Antibodies by Disease Process Systemic Lupus Erythematosus (SLE) Anti-dsDNA antibody. Anti-Smith antibody.
Drug-Induced Lupus Anti-histone antibody.
Diffuse vs. Limited Scleroderma Diffuse: Anti-Scl-70 (anti-topoisomerase I). Limited: Anti-centromere (often called CREST syndrome, with CREST standing for centromere).
Sjogren's Syndrome Anti-SSA (Ro). Anti-SSB (La), which usually occurs in the presence of SSA. SSA is considered the Sjogren-specific antibody, leading to the presence of SSB.
Rheumatoid Arthritis (RA) Anti-CCP (Cyclic Citrullinated Peptide). RF (Rheumatoid Factor) is non-specific.
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More from Step 1 Basics (USMLE)
4.10 Gout and Pseudogout Rheumotology review for the USMLE Step 1 Exam. Gout Caused by uric acid crystal deposition due to purine metabolism. Triggers inflammation when crystals precipitate in cooler joint fluid. Presents with severe, red, and swollen monoarticular joints, often in the big toe. Diagnosis through synovial fluid analysis. Acute treatment: colchicine, NSAIDs, and glucocorticoids. Preventive treatment: allopurinol, febuxostat, probenecid, and lifestyle changes. Pseudogout Resulting from calcium pyrophosphate crystal deposition, often due to ATP breakdown. Manifests with painful, swollen joints, typically affecting multiple upper extremity joints, especially the knee. Diagnosis through synovial fluid analysis. Acute treatment resembles gout management. No direct preventive treatment to lower calcium pyrophosphate levels. Thanks for listening!
4.09 Rheumatologic Emergencies Rheumatology review for USMLE Step 1 Exam Giant Cell Arteritis (GCA) A large vessel vasculitis, mainly in older individuals. Symptoms: headache, jaw claudication, vision loss. Ischemia from granulomas in large vessels causes vision loss. Immediate high-dose corticosteroids are crucial. Scleroderma Renal Crisis A complication of scleroderma. Symptoms: finger edema, skin tightening, sudden hypertension, rising creatinine. Renal artery fibrosis leads to high blood pressure. Treat with IV ACE inhibitor, not steroids. Acute Transverse Myelitis in SLE Inflammation of the spinal cord in lupus. Symptoms: bilateral numbness, tingling, weakness. Treat with corticosteroids. Catastrophic Antiphospholipid Syndrome (CAPS) A rare, life-threatening form of APS. Symptoms: unexplained miscarriages, unexplained clots, multiorgan failure. Treat with anticoagulation followed by immune suppression
1.06 Systolic Heart Murmurs Cardiovascular system review for the USMLE STEP 1 Exam Heart murmurs are caused by turbulent blood flow in the heart
5.13 OCD and Related Disorders Psych review for the USMLE Step 1 Exam Obsessive Compulsive Disorder (OCD): Unwanted thoughts (obsessions) and repetitive behaviors (compulsions). Treat with CBT + SSRIs/SNRIs. Tic Disorders: Tourette Syndrome involves multiple motor and at least one vocal tic. Treat with Habit Reversal Therapy. Body Dysmorphic Disorder: Preoccupation with minor flaws, treat with SSRIs and CBT. Trichotillomania: Hair pulling disorder, treat with Habit Reversal Training and sometimes SSRIs. PANDAS: Pediatric disorder after strep infection, sudden OCD-like symptoms. Treat with antibiotics, CBT, and SSRIs.
5.12 Anxiety Related Disorders Psychiatry review for the USMLE Step 1 Exam Anxiety is a normal response to threats or stressors in the environment Anxiety disorders occur when anxiety causes significant distress or impairment in functioning Generalized Anxiety Disorder (GAD) involves persistent and excessive worry about various aspects of daily life for at least 6 months, accompanied by physical symptoms Treatment for GAD typically involves a combination of cognitive-behavioral therapy (CBT) and selective serotonin reuptake inhibitors (SSRIs) Panic Disorder is diagnosed in individuals who experience spontaneous panic attacks and fear future attacks Panic attacks are acute episodes of intense anxiety and physical symptoms Treatment for Panic Disorder involves CBT and SSRIs, with SSRIs being the first-line medication Agoraphobia is the fear of being in public places where escape may be difficult and often follows a traumatic event CBT and SSRIs are the recommended treatment for Agoraphobia Social Anxiety Disorder (Social Phobia) involves fear of scrutiny or embarrassment in social situations Public speaking can be a significant trigger for individuals with social anxiety disorder Beta blockers can be used to treat social anxiety disorder by reducing physical symptoms Treatment for social anxiety disorder usually involves CBT, SSRIs, or beta blockers.