Term
| How can infection cause anemia? |
|
Definition
| bacterial infections suppress erythropoietin production and the proliferation of erythroid progenitors; and also chronic infections impair iron utilization |
|
|
Term
| Lab results for Iron in anemia of chronic disease |
|
Definition
| low sFe, reduced TIBC, and abundant stored Iron in tissue macrophages |
|
|
Term
| Cause of pure red cell aplasia |
|
Definition
|
|
Term
Infections that lead to aplastic anemia
(4 viruses) |
|
Definition
| hepatitis virus, CMV, EMV, and HSV |
|
|
Term
Infections that lead to hemolytic anemia
(2 parasites) |
|
Definition
Bebesia leads to cell lysis
Leishmania causes production of oxidative metabolic products that lyse RBCs |
|
|
Term
| Bacterial toxins that might cause toxin production |
|
Definition
- alpha toxin in Clostridium perfringens
- Capsular polysaccharide (PRP) of hameophilus influenza type B binds red cell surface and anti-PRP antibodies lyse the cell |
|
|
Term
| Parasitic infection which causes microcytic anemia |
|
Definition
| iron deficiency anemia, associated with Hook Worm |
|
|
Term
| Infections that lead to megaloblastic anemia |
|
Definition
| B12 deficiency accompanying D. Latum infection |
|
|
Term
B19 presentation in various hosts
(child, adult, chronic hemolytic anemia, immunocompromised patient, fetus) |
|
Definition
fifth's disease
polyarthropathy
transient aplastic crisis (TAC)
PRCA Pure red cell aplasia
congenital anemia, hydrops fetalis |
|
|
Term
B19 virus and anemia
(target cell, presentation) |
|
Definition
erythroid progenitor cells and erythroblasts, blood group antigen P
erythema infectiosum, arthalgia, arthritis |
|
|
Term
| What is transient aplastic crisis, what is the presentation and what infection is it associated with? |
|
Definition
TAC is the abrupt cessation of erythropoiesis
reticulocytopenia, absent erthyroid precursors in the bone marrow and precipitous worsening of anemia
B19 associated TAC is found in patients with underlying hemolytic disorders or in patients with high RBC turnover |
|
|
Term
| If a pregnant woman in her second trimester is exposed to parvovirus B19, what thest should be done first? |
|
Definition
| obtain IgG and IgM serology ASAP |
|
|
Term
What would each of the possible serology results of pregnant woman in her second trimester indicate/
- positive IgG result and negative IgM
- positive IgG and IgM
- negative IgG and positive IgM
- negative IgG and negative IgM |
|
Definition
- indicates past infection (no risk to fetus)
- indicates infection with in the last 1-120 days (possible risk to fetus)
- indicates acute infection (higher risk to fetus)
- indicates the mother is not immune and that no evidence of acute infection is noted. Repeat the test in three weeks. |
|
|
Term
Treatments for the following anemias:
- pure red cell aplasia
- aplastic crisis
- HIV |
|
Definition
- intravenous immunoglobulin (IVIG)
- packed RBCs
- HAART |
|
|
Term
| Two target cells of Malaria parasites leading to anemia |
|
Definition
P.vivax binds Duffy blood group antigen
P. falciparum binds to sialic acid residues on glycophorin A |
|
|
Term
Babesia microti
(transmission, population, acute and chronic presentation) |
|
Definition
tick-transmitted protozoan
immunocompromised
inclusions- tends to form ring froms in tetrads
acute- malaise, headache, chills, sweating, periodic fatigue
chronic- hemolytic anemia, renal failure |
|
|
Term
| Symptoms of Hook Worm infrection |
|
Definition
often asymptomatic
iron (microcytic) deficiency anemia
respiratory symptoms, itch, edema |
|
|
Term
D. Latum
(associated anemia, other symptoms, diagnosis) |
|
Definition
B12 deficiency leading to megaloblastic anemia
salt craving, intermittent abdominal discomfort
detection of large operculated eggs in stool or recovery of proglottids |
|
|
Term
Bartonella bacilliformis
(Gram stain, different disease presentations) |
|
Definition
gram-negative rods that penetrate RBCs
carrion disease- acute febrile illness
oroya fever- severe anemia
verruga peruana- blood-filled nodules |
|
|
Term
| 5 common features of H. pylori and C. jejuni |
|
Definition
- spiral or curved shape
- gram negative rods
- low G-C bqase ratio
- inability to ferment or to oxidize carbohydrates
- microaerophilic |
|
|
Term
H. pylori
(urease, H2S production, nitrate reduction, growth at 42 C, shape, size) |
|
Definition
positive
negative
negative
negative
spiral with 3 unipolar flagella
1 x 4 um |
|
|
Term
C. jejuni
(urease, H2S production, nitrate reduction, growth at 42 C, shape, size) |
|
Definition
negative
positive
positive
positive
bipolar flagella
not very wide |
|
|
Term
| Describe the symptoms associated with a C. jejuni infection |
|
Definition
up to 10 stools/day
bloody diarrhea
RUQ pain- often only symptom |
|
|
Term
| Describe the symptoms of a C. fetus infection |
|
Definition
endocarditis, septic thrombophlebitis
arthritis spetic abortion, meningoencephalitis, spontaneous peritonitis |
|
|
Term
| hyatid cysts in the liver |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Treatment of Campylobacter Infections |
|
Definition
fluid and electrolyte replacemnet
empirical antibiotics for patients with high fever or bloody or frequent diarrhea
erthromycin clears in 72 hours |
|
|
Term
| Virulent factor of H. pylori |
|
Definition
| O-side chain resembles the blood group antigens so serve to protect the bacteria from immune clearance |
|
|
Term
|
Definition
| gastric ulcers, MALT (mucus associated tissue lymphoma) |
|
|
Term
|
Definition
PPI
clarithromycin
beta-lactams |
|
|
Term
| bacteria found in scondary periotinitis caused by appendicitis perforation |
|
Definition
| Prevotella melaninogenica |
|
|
Term
| Most important cause of endemic severe diarrheal illness |
|
Definition
|
|
Term
|
Definition
over a week duration
ELISA/Latex agglutination in stool samples
severe if ass. w/ dehydration and electrolyte imbalance
vaccines are available |
|
|
Term
| Explain the role of the NSP4 protein in rotavirus in causing diarrhea |
|
Definition
intracellular release of Ca leading to diarrhea
disrupts tight junction allowing for paracellular flow of H2O and electrolytes
sitmulates the ENS |
|
|
Term
| Name three virulence factors of adenovirus |
|
Definition
inhibition of MHC I expression
E proteins- block apoptosis by binding Rb and p53
VA-RNAS block interferon anti-viral response |
|
|
Term
| General characteristics of Enterobacteriaceae |
|
Definition
Gram-negative rods
motile and facultative anaerobes
LPS is the major cell wall antigen |
|
|
Term
| Distinguish between typhoid and non-typhoid serovars of Salmonella |
|
Definition
typhoid serovars: human-to-human, fecal-oral
non-typhoid: animal or contaminated food handling |
|
|
Term
| Summarize virulence factors employed by Salmonella to establish infection |
|
Definition
attachment to epithelial cells by fimbriae; invade through M cells and enterocytes
replication occurs in the endocytic vacuole; disseminated infection can occur
enterotoxin produced |
|
|
Term
|
Definition
bile salts and crystal violet inhibit gram-positive
fermentation of lactose produces pink |
|
|
Term
|
Definition
Eosin blue and methylene blue inhibit the growth of gram positives
blue or green with lactose fermentation |
|
|
Term
| Discuss the mechanism by which Shigella invades intestinal epithelial cells |
|
Definition
invades M cells of the colon by type III secretion
invades neighbor cells by comet-like actin tail
IL-1 release and PMN migration causes further loss in cell integrity
|
|
|
Term
| Define the mechanism of action of Shiga toxin |
|
Definition
AB subunit is cleaved by the protease furin
the A subunit inhibits protein translation by cleaving 28S rRNA
this causes cellular damage to intestinal epithelium |
|
|
Term
ETEC
(site of action, disease, pathogenesis & virulence factors) |
|
Definition
small intestine
Traveler's diarrhea
enterotoxins stimulate hypersecretions of fluids and electrolytes, colonization factor antigens |
|
|
Term
EHEC
(site of action, disease, pathogenesis & virulence factors) |
|
Definition
large intestine
hemolytic-uremic syndrome
shiga toxin disrupts protein synthesis. A/E lesions on microvilli results in decreased absorption. Bfp, intimin adhesion |
|
|
Term
EIEC
(site of action, disease, pathogenesis & virulence factors) |
|
Definition
diarrhea which progresses to dysentery with bloody stools
invasion mediated by invasive plasmid antigen |
|
|
Term
| Explain how SMAC media aids in the diagnosis of E.Coli. |
|
Definition
| E. coli O157:H7 (EHEC) is the only E.coli strain that does not ferment sorbitol |
|
|
Term
| What is the cause of Hemolytic Uremic Syndrome? |
|
Definition
| Shiga toxin form EHEC damages kidneys which release erythropoietin |
|
|
Term
Yersininae enterocolitica
(general characterisitics, source, CF, Labs) |
|
Definition
gram - rod, intracellular, cold tolerant
contaminated meat
gastroenteritis involving distal ileum, colon, and mesenteric lymph nodes, possible sequelae of autoimmune disorder
lactose negative, urease negative, motility at cold temperatures |
|
|
Term
After three days of vacationing in the city of Lima, Peru, a newly married couple fall ill with what appears to be the same condition. Both experience vomiting, watery diarrhea, nausea, and abdominal cramps. An analysis of their stool results in the isolation of gram-negative rods which produce colonies on MacConkey that are pink Which of the following is the most likely causative microorganism? |
|
Definition
| E. coli (is a lactose fermenter) |
|
|
Term
| A 28-year-old woman complains of painful swelling of the right knee and and tender skin eruptions on both shins. For the past two weeks she has also had watery diarrhea that developed after she consumed some raw pork. She also complains of low-grade fever and mild abdominal pain. Both red and white blood cells were observed in her stool sample. A stool sample revealed a gram-negative rod that was only motile at temperatures below 30°C. Clear colonies on MacConkey agar |
|
Definition
| Yersiniae enterocolitica ( motility below 30 C) |
|
|
Term
| A 16-year-old boy is brought to the emergency room by his parents, as he has been experiencing bloody diarrhea for 1 week. He also complains of not urinating often and blood in his urine when he does. His laboratory studies demonstrate an increased BUN and creatinine and the presence of gram-negative rods which produce beige colonies on SMAC and colonies on EMB as shown below (green). The condition is associated with infection by which of the following E. coli types? |
|
Definition
|
|
Term
| A 36-year-old man comes to the emergency room because of the development of sudden nausea, vomiting, and diarrhea with blood and mucus, as well as crampy abdominal pain. He had just returned yesterday from a business trip to South America and has been experiencing these symptoms for two days. Leukocytes were found in his stools as well as a gram-negative non-motile rod. Growth on MacConkey media after 48 hours shows clear colonies. Which of the following is the most likely causative microorganism? |
|
Definition
| Shigella dysenteriae (non-motile, non-lactose fermenter) |
|
|
Term
| A 3-year-old man presents with sudden-onset, crampy abdominal pain and diarrhea. The diarrhea is watery and contains mucus. The patient also complains of low-grade fever with chills, malaise, nausea, and vomiting. Careful history reveals that he had ingested partially cooked eggs at a poultry farm 24 hours before his symptoms began. Based on this limited information, which of the following microorganism would you most likely suspect? |
|
Definition
| Salmonella enterica (sudden, mucus, poultry) |
|
|
Term
| A 3-month-old female infant was brought to the emergency department of a general hospital with a 5-day history of decreased activity, decreased oral intake, upper airway congestion, and general irritability. There was no history of fever or vomiting. During the previous 2 weeks, she had been constipated, and twice her mother had given a tablespoon of honey for treatment. The physical examination revealed dry oral mucosa, a sluggish pupillary response, and significant hypotonia. A gram stain of the fecal sample revealed a gram positive spore forming rod. Which of the following is the most likely diagnosis? |
|
Definition
| C. Botulism (flaccid paralysis) |
|
|
Term
| A 67-year-old man presented with fever, abdominal cramping, and frequent diarrhea for four days. Three weeks before the current episode, he had undergone a hip replacement and was rehabilitating in an orthopedic unit. During the hospitalization, he developed a nosocomial pneumonia and was treated empirically with clindamycin. He gradually improved and was discharged a week before his current presentation, with maintenance oral antibiotics. Which of the following is the most likely diagnosis? |
|
Definition
| Shigella sonnei (nosocomial infection) |
|
|
Term
C. difficile
(CF, and A and B toxins) |
|
Definition
pseudomembranous colitis
A- enterotoxin--> recruits PMNs
B- causes cytoskeletal damage |
|
|
Term
C. perfringens
(LF and A and B toxins) |
|
Definition
lechtinase enzyme destoys cells
causes precipitate growth on egg yolk agar
A enterotoxin disrupts ion transport
B enterotoxin forms pores--> bloody diarrhea |
|
|
Term
|
Definition
1-3 days of weakness, blurred vision, and constipation
flaccid paralysis
canned foods |
|
|
Term
| Specifics about two forms of Bacillus Cereus |
|
Definition
emetic and diarrheal form
diarrheal form lasts longer, from meat and is heat labile |
|
|
Term
Giardia lambia
(transmission, symptoms, E, D) |
|
Definition
fecal-oral
diarrhea, increased fat and mucus in stool
worldwide, primarily human-to-human transmission
cysts (stain with Trichrome stain)and smiley-face trophozoite (stain with Kohn and Giemsa stain) forms are detected in feces |
|
|
Term
| What stain is diagnostic for Cryptosporium? |
|
Definition
| acid-fast stain, it won't stain with trichrome |
|
|
Term
| What is the treatment for cryptosporidium infection? |
|
Definition
| hydration, no drugs are effective against crypto |
|
|
Term
Cryptosporidium
(Et, Sx, E, D) |
|
Definition
fecal-oral
frothy BMs, anorexia, self-limiting, immunocompromised pateints cannot self cure
oocysts, acid fast stain |
|
|
Term
Balantidium coli
(E, Sx, E, D) |
|
Definition
fecal-oral
intermittent diarrhea with blood and pus, ulceration
worldwide, swine #1 animal reservoir
microscopic exam, bean-shaped macronucleus |
|
|
Term
| How does the O/P of E. histolytica read? |
|
Definition
| trichrome stain shows ingested red blood cells |
|
|
Term
E. histolytica
(Et, Sx, E, D) |
|
Definition
fecal-oral
dysentery, RUQ
worldwide, human-to-human
microscpic exam, motile trophozites
PCR differentiate histolytica from dispar |
|
|
Term
| O/P of Ascaris lumbricoides |
|
Definition
| large, mamillated coat and tapered end in fertilized egg |
|
|
Term
| O/P of stengyloides stercoralis |
|
Definition
| muscular neck, distinguished from hookworm by mouth at one end and notched tail on the other |
|
|
Term
| O/P of schistosoma mansoni |
|
Definition
| large spine projecting out of one side |
|
|
Term
| Life cycle of ascaris lubricoides |
|
Definition
ingested eggs travel to the lunges
larvae break free
in 3 weeks larvae pass and can be swallowed back into the small intestine |
|
|
Term
|
Definition
| white worm , barrel shaped eggs with mucoid plugs at both ends |
|
|
Term
Trichuris trichiura
(Et, Sx, E, D) |
|
Definition
fecal-oral
diarrhea, rectal prolapse in children
Worldwide
concentrated microscopic specimen |
|
|
Term
Schistosoma mansoni
(Et, Sx, E, D) |
|
Definition
skin penetration by cercariae from snails
dermatitis, enlarged liver and lymph nodes, eosinophilia and dysentery
South America and Africa
schistosome eggs in stool and urine |
|
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