2011 First Aid for the USMLE Step 1 Official Updates, Corrections, and Clarifications

Updated March 1, 2011 Despite our best efforts, errors do occur during the revision. If you see a verifiable error not on this list, please report it to our blog at www.firstaidteam.com. If you are the first to report the error, you will receive a $10 gift certificate. In order to identify and correct every possible error, we review every single submission, as well as search other websites and blogs that claim to have a comprehensive listing of errors in First Aid 2011. If you find that our material conflicts with a source that you’re reviewing, please point us toward it with a corroborating reference. As always, we will check every submission against primary references to ensure the most accurate, high-yield study guide available. If you submitted an erratum and it does not appear in an update, then either it does not agree with the primary literature in the field or we consider it a detail beyond the scope of the book. Please note that we will not list simple typos or, unless egregious, omitted material; our goal is to provide a high-yield framework for studying and not a comprehensive textbook. The list below reflects content errors and typos that may create confusion that were submitted before February 8, 2011. As always, updates are available at www.firstaidteam.com. Good luck with your studies!

–The First Aid/USMLERx Team

Page # Entry Title Correction/Clarification

6 Rescheduling an exam

In the second full paragraph, change "To avoid a rescheduling fee, you will need to request a change before noon EST at least five business days before your appointment" to "No fee is charged for changing your testing appointment 31 or more calendar days prior to the first day of the scheduled test."

62 Sleep stages Shift the reference to “sleep spindle” in the figure slightly to the left.

71 DNA/RNA/Protein synthesis direction

Note that the figure should illustrate the phosphodiester linkage between the top two deoxyribonucleotides which is an important component of the DNA backbone, and also crucial for binding of phosphodiesterases.

91 VitaminB2 (riboflavin) ”The 2 C’s” entry in column 3 should align with the entry for Deficiency.

107 Catecholamine synthesis

(1) The arrows for dihydropterin reductase reaction are both pointing the wrong direction. The enzyme should recover THB from DHB and make NADP+ from NADPH. Reverse the arrows. (2) Change “Dopamine ß-hydroxylase” to “Dopamine.”

123 Heart embryology Change the entry for "Primitive ventricle" to "Trabeculated parts of right and left ventricles.”

127 Posterior fossa malformations Change Chiari II to Chiari I.

128 Branchial arch derivatives

The list of muscles of pharyngeal arch 1 includes the anterior 2/3 of the tongue. While it is true that CN V supplies somatic sensation to the mucosa of the tongue via the lingual nerve, it does not innervate any of the muscles of the tongue. All of the muscles of the tongue are innervated by CN XII, with the exception of CN X's contribution by innervating the palatoglossus.

132 Kidney embryology In the last line of text, change “uteropelvic” to “ureteropelvic.”

138 Special culture requirements Change the media used for isolation for Legionella to include iron in addition to cysteine.

149 Leprosy (Hansen’s disease)

Note that tuberculoid disease is the result of high cell-mediated immunity with a largely Th1-type immune response, and lepromatous leprosy is characterized by low cell-mediated immunity with a humoral Th2 response.

152 Helicobacter pylori

Include a third, and newest, triple therapy for H. pylori, (3) proton pump inhibitor, clarithromycin, and either amoxicillin or metronidazole.

168 RNA viruses In the entry for Reoviruses, note that coltivirus (not reovirus) is the cause of Colorado tick fever.

180 Red rashes of childhood Revise the clinical presentation of Mumps virus to include rash.

181 Sexually transmitted diseases

In the entry for bacterial vaginosis, note that it can be sexually transmitted, but it is not exclusively an STD.

181 Pelvic inflammatory disease

Change the statement "C. trachomatis --the most common STD in the United States" to "C. trachomatis -- the most common bacterial STD in the United States."

200 Lymph drainage

In item 6 under “Area of body,” change “Anal canal below” to “Anal canal below pectinate line" with “primary lymph drainage to the superficial inguinal nodes.”

207 Complement Change the classical pathway convertase for C3 from C4b,2b to C4b2a.

213 Immune deficiencies

Under Bruton's agammaglobulinemia, in the Defect column, change “blocks B-cell differentiation/maturation” to “blocks pro-B cell from forming pre-B cell.”

216 Sirolimus (rapamycin) Note that sirolimus inhibits (not binds to) mTOR.

220 Necrosis In item 5, change “Fibroid” to “Fibrinoid.”

222 Free radical injury In item 3, change “CCi4” to “CCl4” (carbon tetrachloride).

229 Oncogenic microbes Under EBV, add Hodgkin’s lymphoma.

229 Paraneoplastic effects of tumors

Under “Neoplasm,” change “Renal cell carcinoma, hemangioblastoma” to read “Renal cell carcinoma, hemangioblastoma, hepatocellular carcinoma, pheochromocytoma.

246 Alcohol toxicity Change text in first paragraph to “”conversion of lactate to pyruvate…”

272 Types of infarcts

Change the entry under Subendocardial infarcts to "Subendocardium especailly vulnerable to ischemia due to fewer collaterals, higher pressure." (all on one line.)

276 Rheumatic heart disease Change the title of the Fact from “Rheumatic heart disease” to “Rheumatic fever.”

305 Propylthiouracil, methimazole Propylthiouracil can also cause hepatotoxicity.

310 Digestive tract anatomy In the diagram, change “Mucularis mucosae” to "Mucularis mucosa."

313 Portosystemic anastomoses Delete the number “4” from the diagram.

318 GI secretory products Change the text under Pepsin regulation, third column,to “…stimulation and local…”

319 Gastric parietal cell Move the reference to “Gastric lumen” to the other side of the diagram under “Gastric parietal cell.”

320 Carbohydrate digestion Under “Salivary amylase,” change “dextrans” to “dextrins.”

327 Meckel’s diverticulum Change “Dx: Pertechnetate. Study for ectopic uptake.” to “Dx: Pertechnetate study for ectopic uptake.”

333

Wilson’s disease (hepatolenticular degeneration)

(1) Remove "Choreiform movements" from the list of characteristic features.

(2) Next to "Dementia," add dyskinesia and dysarthria.

335 Gallstones (cholelithiasis)

In reference to biliary colic, remove the phrase that states, "... cause bile duct obstruction which results in bile duct contraction." It is a repeat of the previous sentence.

346 Platelet plug formation Change the Adhesion box entry to “Platelets bind vWF via GpIb receptor at the site [not side] of injury only (specific).”

350 Normocytic, normochromic anemia

Remove G6PD deficiency from extravascular hemolysis and include under intravascular hemolysis.

352 Intrinsic hemolytic normocytic anemia

Note that the text “synthesis of GPI anchor” appears twice near the bottom of the page. Delete one occurrence of this text.

358 Multiple myeloma

Note that the M protein in multiple myeloma is most commonly IgA or IgG. Multiple myeloma cells produce excessive monoclonal proteins, called M proteins, and are recognized as IgA, IgD, IgG, IgE, IgM. The M protein level is referred to as the M-spike.

359 Leukemias

Change the CML Comments to "Responds to imatinib (a small molecule inhibitor of the bcr-abl tyrosine kinase).” Imatinib is not an antibody.

361 Chronic myeloproliferative disorders

Shift the second CML label down one line so that it aligns with "bcr-abl transformation leads to..."

361 Polycythemia

(1) Note that RCC, Wilms' tumor, cyst, HCC, and hydronephrosis are associated diseases of inappropriate absolute polycythemia due to ectopic erythropoietin. (2) Note that EPO is increased (not decreased) in polycythemia vera.

362 Heparin Note that the "decrease" sign in the first sentence refers to both thrombin and Xa levels.

374 Upper extremity nerves

(1) Change “Median (C6-C8, T1)” to “Median (C5-C8, T1).” (2) In the third column, the “ape hand” description should indicate that a distal median nerve lesion can also cause “ape hand.” (3) The median motor deficits are transposed. Switch the positions of “Lateral finger flexion/wrist flexion” and “Opposition of thumb.”

386 Polymyositis/dermatomyositis There is no perifascicular inflammation in polymyositis. In dermatomyositis, perifascicular atrophy is sufficient for diagnosis.

389 Skin disorders (continued) Include a reference to image 66 in the description of acanthosis nigricans.

397 Neurotransmitters Note that Ach in REM sleep is increased, not decreased.

399 Thalamus

(1) Change the VPL reference from "position and proprioception” to “pressure, touch, vibration, and proprioception." (2) Note that the input of the MGH is the superior olive and inferior collculus of tectum [not pons].

423 Cranial nerve III in cross-section

Note that the output to ocular muscles is due to decreased [not increased] diffusion to interior.

423 Visual field defects

In item 7, central scotoma, change the image of the left eye to show a dark circle in the middle as opposed to being completely shaded in.

426 Seizures Note that partial seizures most commonly originate in the medial [not mesial] temporal lobe.

429 Herniation syndromes Redirect arrow 3 from the uncus through the tentorium cerebelli.

442 Neurotransmitter changes with disease Under Huntington’s disease, add “↑ dopamine.”

450 Signs and symptoms of substance abuse

Under “alcohol,” add a period after "Serum γ-glutamyltransferase (GGT) - sensitive indication of alcohol use"

451 Signs and symptoms of substance abuse

The top of page 451 is a continuation of Signs and symptoms of substance abuse from page 450. The top of page 451 should be changed to include the title, “Signs and symptoms of substance abuse (continued).”

461 Nephron physiology

(1) In the upper left drawing, within the proximal convoluted tubule, show that H2CO3 splits into H+ and HCO3

- and the H+ then goes into the lumen and the HCO3 goes into the interstitium. (2) In the lower right drawing, change the label from “Distal convoluted tubule” to “Collecting tube transport.”

467 Nephritic syndrome

For Alport’s syndrome, change “deafness X-linked dominant” to “deafness X-linked.” Transmission of Alport's syndrome can be X-linked, autosomal recessive, or autosomal dominant.

468 Nephrotic syndrome

Note that focal segmental glomerulosclerosis, not membranous glomerulonephritis, is the most common cause of adult nephrotic syndrome.

469 Kidney stones

Under Ammonium magnesium phosphate, in the Notes column, delete “magnesium”; these stones are caused by infection with urease-positive or radiolucent bugs.

470 Transitional cell carcinoma In the right column, insert a comma between “Smoking” and “Aniline dyes.”

479 Derivation of sperm parts Note that some text is repeated: "and flagellum (tail) from one of the centrioles" and "Tail forms from centrioles."

519 Classic presentations

In the diagnosis/disease associated with “hypertension, hypokalemia, metabolic acidosis,” delete the “1° hyperaldosteronism” in parentheses.

524 Classic labs/findings

(1) In the diagnosis/disease associated with “Hair-on-end (crew-cut) appearance on x-ray,” change extramedullary hematopoiesis to marrow expansion. (2) Hilar lymphadenopathy, peripheral granulomatous lesions in middle or lower lung lobes” is associatd with a Ghon complex (not a Ghon focus).

604 Endocarditis

Add these pages to the index entry: 275, bacterial endocarditis 275, Libman-Sacks endocarditis

I-21 Image 86A Change “hyercellularity” to “hypercellularity.”