Show Notes
5.10 Mood Disorders (Depression and Bipolar) Psychiatry Review for the USMLE Step 1 exam Mood disorders are persistent disruptions in emotion, categorized into bipolar disorders and depressive disorders. Bipolar disorders are characterized by manic or hypomanic episodes, while depressive disorders feature periods of depression. Major Depressive Disorder (MDD) is characterized by feelings of sadness, guilt, worthlessness, and anhedonia lasting for at least two weeks. SIG E CAPS is an acronym used to remember the symptoms of depression: Sleep changes, Interest loss, Guilt, Energy loss, Concentration difficulties, Appetite changes, Psychomotor retardation, and Suicidal ideation. In MDD, at least 5 of the SIG E CAPS symptoms must persist for more than 2 weeks. Persistent Depressive Disorder (dysthymia) is a chronic, low-grade form of MDD that lasts for at least two years. Mania is a symptom common to all bipolar disorders, characterized by elevated or irritable mood and increased activity or energy. Mania lasting for at least 1 week is called a manic episode, while hypomania is a less severe form lasting longer than 4 days. The symptoms of mania can be remembered using the mnemonic DIG FAST: Distractibility, Irritable mood/insomnia, Grandiosity, Flight of ideas, Agitation/increased activity, Speedy thoughts/speech, and Thoughtlessness. Bipolar I involves manic episodes, and bipolar II involves hypomanic episodes and major depressive episodes. Bipolar I requires at least one manic episode, while bipolar II requires depressive episodes. Mood stabilizers such as lithium, valproate, carbamazepine, and lamotrigine are used to treat bipolar disorders. Litium is the best (notable exeptions however). Antidepressants are contraindicated for bipolar patients due to the risk of flipping into mania. The risk of suicide is high in bipolar patients, with 25-50% attempting suicide and 10-15% dying by suicide. Cyclothymia is a less common form of bipolar disorder characterized by cycling between hypomania and mild depression over many years.
More from Step 1 Basics (USMLE)
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.
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.