Slide 1General CommentsTh1 versus Th2Hemolytic disease of the newborn (HDN)Hemolytic disease of the newborn (HDN):Question 1Slide 7Question1Question 2Question 2Question 3Question 3Questions 4&5Culture on TCBS (Thiosulfate Citrate Bile Sucrose)Question 4Question 5Question 6Question 6Question 7Question 7Question 7Question 8Question 8Question 9Question 10Question 10Question 11Question 12Question 12Questions 13&14Satellite test is performedQuestion 13Question 14Question 15Question 15Question 16Question 16Question 23Question 23Slide 40Slide 41Questions 29-31Questions 29-31Questions 29-31 Culture and Gram stainQuestion 29: The lesion is a manifestation ofQuestion 30 What is the most likely cause? Bacillus anthracisQuestion 31Question 32Question 32Question 33Question 34Question 34Question 37Question 37Question 38Question 38Question 38Question 39Question 39Question 40Question 41Question 42Question 43Question 44Question 45Question 45Question 46Question 47Question 48Question 48Slide 71Comprehensive FinalReview Medical Microbiology PotpourriGeneral Comments•Exam format (80 questions)–Multiple choice, ~1/2 with associated images–Questions similar to, or identical to those on previous exams–Less emphasis on virology section•Review Lab material again – selective media, TSI agar slants etc.Th1 versus Th2•Th1: IL-2, IL-3, IFN-, TNF-–↑bactericidal activities of macrophages–Induces B cells to make opsonizing and complement-fixing antibodies–Cell mediated immunity•Th2: IL-4, IL-5, IL-6, IL-10, IL-13–Induces B cells to make neutralizing non-cytolytic antibodies–Humoral immunityHemolytic disease of the newborn (HDN)Rh incompatibility  pregnant woman has Rh- blood, fetus has Rh+ blood1st PregnancyFetal RBCs cross placental barrier  stimulate antibody response to Rh D antigens2nd PregnancyRh D IgG Abs cross placental barrier and attack fetus’ RBCs  anemia (and death)Hemolytic disease of the newborn (HDN): Rho(D) Immune Globulin (RhoGAM)  IgG antibodies that bind to Rh D antigens on fetal red blood cells  prevents sensitizationRhoGAM administered at 28 weeks in cases where mother is D –ve and father is D +veRhoGAM adminstered within 72 hours of delivery if mother is D –ve and baby is D +veQuestion 1A 61-year-old woman was admitted to the hospital because of increasing pain in both shoulders and upper arms. On day one after the admission, she awoke with severe pain in both of her arms. Her temperature was 34.6°C (low), pulse rate 112/min (high), respiration rate 26/min (high) and blood pressure 85/55 mmHg (low). Blood cultures were obtained (Images 1&2). The patient deteriorated rapidly and died of septic shock shortly after the admission.Question 1Culture Gram stainQuestion1•Which of the following had contributed most to the pathogenesis of her septic shock? –A. Pyocyanin–B. Oxidase –C. Exotoxin A–D. Endotoxin (LPS)–E. Toxic shock syndrome toxin (TSST)Question 2A 30-year old man develops necrotizing fasciitis, followed by widespread rash, hypotension and multiple organ system failure. His blood culture is positive for which organism?Strep PyogenesQuestion 2•Which of the following has contributed most to the pathogenesis of his disease?–A. Streptococcal pyrogenic exotoxin–B. Toxic shock syndrome toxin –C. Staphylococcal enterotoxin–D. Endotoxin–E. Streptolysin OQuestion 3A 2-year-old boy presents with sore throat and enlarged cervical lymph nodes (“bull’s neck”). Throat culture reveals the following. Methylene blue stainTinsdale agarWhat is your diagnosis? Diphtheria- Corynebacterium diphtheriaQuestion 3The patient is at risk of developing? A. airway obstructionB. cardiomyopathyC. neuropathyD. all of the aboveQuestions 4&5•A 2-year old boy living in a small village in India develops large volume watery diarrhea with “rice water” stools. He is rushed to the nearest hospital where he receives IV fluids. His stool culture is positive for the following organisms.Culture on TCBS (Thiosulfate Citrate Bile Sucrose) Gram StainQuestion 4•What is the most likely cause? –A. Cryptosporidium parvum–B. Entamoeba histolytica–C. Shigella dysenteriae–D. Vibrio cholerae–E. Rotavirus What other GI bacteria appear as comma-shaped rods?Helicobacter pylori, Campylobacter jejuniQuestion 5•What is the most likely pathomechanism involved?–A. Ulceration of intestinal mucosa–B. Upregulation of the chloride channel –C. Blunting of intestinal villi –D. Decreased disaccharidase activity–E. Inhibition of protein synthesisQuestion 6•A 3-year old girl who lives on a farm in the Midwest develops bloody diarrhea. Her stool culture is positive for a non-motile enteric rod. K/A, gas -, H2S - Indole -Urease -Question 6•What is the most likely cause?–A. Shigella sonnei–B. Salmonella enterica–C. Giardia lamblia–D. Campylobacter jejuni–E. Entamoeba histolyticaQuestion 7•A 25-year old man develops difficulty walking, chewing and talking several weeks after a self-limited diarrheal disease caused by this organism.Question 7•Skirrow medium•Gram stainWhat is the bacterium? Campylobacter jejuniQuestion 7 •What is the most likely diagnosis?–A. Guillain-Barré syndrome–B. Waterhouse-Friderichsen syndrome–C. Acute rheumatic fever–D. Reactive arthritisQuestion 8•A 5-year old boy presents with productive cough and wheezing. Atypical pneumonia is suspected and he is placed on Augmentin (amoxicillin with clavulanic acid). Clavulanic acidBeta-lactam ringQuestion 8•A 5-year old boy presents with dry cough and wheezing. Atypical pneumonia is suspected and he is placed on Augmentin. The rationale for using clavulanic acid in this drug combination is inhibition of the enzyme?–A. Dihydrofolate reductase–B. Transpeptidase–C. Beta-lactamase–D. DNA nuclease–E. N-glycosidaseQuestion 9•A 20-year old sexually active woman presents with frequent and painful urination. Which of the following are likely to be recovered from her urine sample?–A. Ureaplasma urealyticum or Enterococcus faecalis–B. Trichomonas vaginalis or Staphylococcus epidermidis–C. Staphylococcus saprophyticus or Escherichia coli –D. Streptococcus agalactiae or Proteus mirabilisQuestion 10Shortly after arrival to Mexico for the spring break, a 20-year old man develops large volume watery diarrhea. MacConkey Agar A/A, gas +, H2S - Indole +Urease -Question 10Shortly after