Chapter 22 Flashcards
(156 cards)
1
Q
What are the predominant bacterial types found in normal oral cavity biota?
A
Prevotella, Treponema, Streptococcus, Actinomyces, Neisseria, Veillonella, Lactobacillus
2
Q
What are the predominant bacterial types found in the esophagus and stomach?
A
Streptococcus, Staphylococcus, Clostridium, Bacillus
3
Q
What are the predominant bacterial types found in the large intestine?
A
Bacteroides, Fusobacterium, Bifidobacterium, Clostridium, Streptococcus, Peptostreptococcus, Lactobacillus, Escherichia, Enterobacter
4
Q
What is the most common infectious disease of human beings?
A
Dental caries
5
Q
What is involved in the process of tooth decay?
A
dissolution of solid tooth surface due to the metabolic action of bacteria
6
Q
What are the symptoms of dental caries?
A
A range from minor disruptions in the enamel surface to complete destruction of the enamel and deeper tooth layers
7
Q
What is the pulp?
A
soft tissue inside the tooth that contains blood vessels and nerves
8
Q
What two bacterial species are the most common causes of dental caries?
A
Streptococcus mutans and Streptococcus sobrinus
9
Q
Which bacterial species is commonly seen in early childhood dental caries?
A
Scardovia wiggsiae
10
Q
What substance must be present in order for bacteria to cause tooth decay?
A
Dietary carbohydrates
11
Q
How are the bacteria that cause dental caries transmitted?
A
Through close contact with caregivers/other people
12
Q
How are dental caries diagnosed?
A
Based on tooth condition
13
Q
How are dental caries prevented?
A
dietary restriction of carbohydrates, routine brushing and flossing, fluoride treatment
14
Q
How are dental caries treated?
A
removal of the affected part of the tooth, restoration of tooth with artificial material
15
Q
What is periodontal disease?
A
Inflammation of the gums/gingiva due to bacterial colonization
16
Q
What is the initial stage or periodontal disease?
A
Gingivitis
17
Q
What are the symptoms of gingivitis?
A
swelling, loss of normal gingival contour, patches of redness, increased bleeding of the gingiva
18
Q
If gingivitis progresses to periodontitis, what symptoms can result?
A
increase in pocket size, bone resorption severe enough to loosen the tooth out of the socket, tooth loss
19
Q
Which bacteria, sometimes present in the gingival crevice, is an important contributor of periodontal disease?
A
Methanobrevibacter oralis
20
Q
What is calculus?
A
Dental deposit formed when plaque mineralizes with calcium and phosphate crystals
21
Q
How does oral cavity bacteria associate to cardiovascular health?
A
those with higher numbers of bacteria associated with periodontitis tend to have thicker carotid arteries and increased rates of cardiovascular disease
22
Q
How are the bacteria associated with periodontal disease transmitted?
A
Close contact
23
Q
How is periodontal disease diagnosed?
A
Appearance of the oral tissues
24
Q
How can periodontal disease be prevented?
A
Regular brushing and flossing
25
How can periodontal disease be treated?
Mechanical procedures, such as scaling, at a dental office, surgery to reduce pocket sizes; antibiotic therapy
26
What are the two most destructive periodontal diseases?
necrotizing ulcerative gingivitis (NUG) and necrotizing ulcerative periodontis (NUP)
27
What bacterial species are involved in NUG and NUP?
Treponema vincentii, Prevotella intermedia, Fusobacterium species
28
What symptoms are associated with NUG and NUP?
severe pain, bleeding, pseudomembrane formation, necrosis
29
How are NUG and NUP treated?
removal of damaged periodontal tissue followed by targeted antibiotics
30
What is mumps?
a self-limited, mildly epidemic illness associated with painful swelling at the angle of the jaw
31
What are the signs and symptoms of mumps?
fever, nasal discharge, muscle pain, malaise, inflammation of the salivary glands, swelling of the parotids glands (parotitis)
32
What is mumps pancreatitis?
a variation of mumps in which the virus replicates in the beta cells and pancreatic epithelial cells
33
What are the symptoms of mumps meningitis?
fever, headache, stiff neck
34
What are the characteristics of the mumps virus?
enveloped, single-stranded RNA virus, genus Paramyxovirus
35
What is the main virulence factor of the mumps virus?
Ability to form syncytia
36
How is the mumps virus transmitted?
salivary and respiratory secretions
37
How is mumps diagnosed?
ELISA testing or PCR testing
38
What is gastritis?
Sharp or burning pain emanating from the abdomen
39
What are gastric ulcers?
lesions in the mucosa of the stomach
40
What are duodenal ulcers?
lesions in the mucosa of the uppermost portion of the small intestine
41
What symptoms can accompany gastric ulcers?
bloody stools and vomiting
42
What is the causative agent of gastritis and gastric ulcers?
Helicobacter pylori
43
Why do people with type O blood type have a higher incidence of gastric ulcers?
One specific receptor for H. pylori is also the molecule that confers the O blood type
44
How is H. pylori transmitted?
Oral-oral and fecal-oral routes
45
How is H. pylori diagnosed?
Urea breath test, stool test
46
How is H. pylori treated?
clarithromycin
47
What is the main cause of acute diarrhea cases in the US?
Contaminated food
48
What are the most common causative agents of acute diarrhea in the US?
norovirus, Salmonella, Clostridium perfringens, Campylobacter, Staphylococcus aureus
49
What are the characteristics of Salmonella?
Gram-negative, motile, ferment glucose, produce hydrogen sulfide
50
What is typhoid fever?
enteric fever caused by the Salmonella enterica serotype Typhi
51
Which S. enterica serotypes commonly cause illness in the U.S.?
Typhimurium, Enteritidis, Heidelberg, Newport, and Javiana
52
What are the symptoms of Salmonellosis?
fever, septicemia, vomiting, diarrhea, mucosal irritation, blood in stool
53
What is the typical treatment for Salmonellosis?
fluid and electrolyte replacement
54
What treatment is used for severe Salmonellosis cases?
ciprofloxacin
55
What are the characteristics of the Shigella bacteria?
gram-negative, straight rods, non-motile, non-endospore forming
56
How are Shigella infections diagnosed?
Stool culture
57
What are the symptoms of Shigellosis?
frequent, watery stools; fever; intense abdominal pain; nausea; vomiting, dysentery (bloody diarrhea)
58
What is enterotoxin?
an exotoxin that affects the cells of the GI tract
59
What is shiga toxin?
A heat-labile exotoxin produced by some Shigella species and E. coli O157:H7
60
How is shigellosis transmitted?
Oral routes, direct person-to-person contact
61
What treatment is recommended for shigellosis?
ciprofloxacin
62
What is STEC?
Shiga-toxin-producing E. coli
63
What is hemolytic uremic syndrome?
a severe hemolytic anemia that can lead to kidney damage/failure and is caused by shiga-toxin-producing E. coli
64
In addition to hemolytic uremic syndrome, what other symptoms are associated with STEC?
blindness, seizure, stroke
65
What are enterocytes?
Gut epithelial cells
66
How is STEC diagnosed?
Stool culture, ELISA test, PCR test, PFGE
67
How is STEC prevented?
Heat treatment to kill the bacteria
68
What symptoms are associated with Enterotoxigenic E. coil (ETEC)?
watery diarrhea, low-grade fever, nausea, vomiting
69
What symptoms are associated with Enteroinvasive E. coli (EIEC)?
bacillary dysentery, blood and mucus in stool, high fever
70
What symptoms are associated with Enteropathogenic E. coli (EPEC)?
profuse, watery diarrhea; fever; vomiting
71
What symptoms are associated with Enteroaggregative E. coli (EAEC)?
chronic diarrhea among children and AIDS patients
72
What symptoms are associated with Diffusely Adherent E. coli (DAEC)?
development or urinary tract infections in addition to acute diarrhea
73
What are the symptoms of Campylobacteriosis?
frequent, watery stools; fever, vomiting, headache, severe abdominal pain
74
Which Campylobacter species most commonly causes GI disease in humans?
Campylobacter jejuni
75
What are the characteristics of Campylobacter?
slender, curved or spiral, gram-negative, polar flagella
76
How are Campylobacter species transmitted?
ingestion of contaminated food and drink
77
What is Guillain-Barre Syndrome?
a syndrome characterized by acute paralysis, often onset after a Campylobacter infection
78
What treatment is given for Campylobacter infections?
Fluid and electrolyte replacement, azithromycin if needed
79
What are the characteristics of Clostridioides difficile?
gram-positive, endospore-forming, rod-shaped
80
What is the causative agent of pseudomembranous colitis?
Clostridioides difficile
81
What are the symptoms of pseudomembranous colitis?
diarrhea, abdominal cramps, fever, leukocytosis
82
What is the treatment for C. difficile?
metronidazole if mild; vancomycin if severe; fecal transplant
83
What are the characteristics of vibrios?
comma-shaped rods, single polar flagellum, fermentative
84
What are the symptoms of Vibrio cholerae?
vomiting, secretory diarrhea, rice-water stool, loss of blood volume, acidosis, potassium depletion, hypotension, tachycardia, cyanosis, collapse from shock
85
What conditions favor the spread of V. cholerae?
warm, monsoon, alkaline, and saline conditions
86
How is V. cholerae diagnosed?
stool sample culture, dark-field microscopy
87
What is the key to cholera therapy?
Replacement of fluid and electrolytes
88
What two Vibrio species are more prominent in the United States?
V. vulnificus and V. parahameolyticus
89
What is cryptosporidium?
an intestinal protozoan of the apicomplexan type
90
What are the symptoms of cryptosporidium infection?
headache, sweating, vomiting, severe abdominal cramps, diarrhea
91
How is cryptosporidium diagnosed?
ELISA or acid-fast staining of fecal samples or biopsies
92
What are the characteristics of rotavirus?
member of Reovirus group, double-stranded RNA genome, inner and outer capsid
93
What is the primary viral cause of moribidity and mortality as a result of diarrhea?
Rotavirus
94
How is rotavirus diagnosed?
Rapid antigen testing, ELISA testing
95
How is Rotavirus transmitted?
Fecal-oral route, such as through food, water, or fomites
96
Which virus is the most common cause of foodborne illness in the US?
Norovirus
97
How is norovirus transmitted?
Fecal-oral route, via contaminated food or water
98
What are the symptoms of norovirus?
watery diarrhea, severe vomiting, mild fever
99
What three bacterial species are typically responsible for producing food poisoning via an exotoxin?
Staphylococcus aureus, Bacillus cereus, Clostridium perfringens
100
What symptoms are associated with S. aureus exotoxin food poisoning?
Cramping, nausea, vomiting, diarrhea
101
What are the two exotoxins produced by B. cereus?
One that causes a diarrheal form of the food poisoning disease and one that causes an emetic form of the food poisoning disease
102
What is the definition of chronic diarrhea?
Diarrhea that lasts longer than 14 days
103
What is a distinguishing factor of enteroaggregative E. coli?
The ability of the bacteria to adhere to human cells in aggregates rather than as single cells
104
How is EAEC transmitted?
Contaminated food and water
105
How is EAEC diagnosed?
Genotypic methods, such as PCR
106
What is Cyclospora cayetanensis?
a protozoan pathogen spread through fecal-oral transmission of sporulated oocysts
107
How is C. cayetanensis diagnosed?
Bright-field or phase-contrast microscopy; PCR testing
108
What are the symptoms of C. cayetanensis?
Watery diarrhea, stomach cramps, bloating, fever, muscle aches, anorexia, weight loss
109
What is the drug of choice for treating C. cayetanensis?
trimethoprim-sulfamethoxazole
110
What is Giardia lamblia?
a pathogenic flagellated protozoan
111
What are the typical symptoms of Giardiasis?
diarrhea of long duration, abdominal pain, flatulence
112
How is G. lamblia transmitted?
Contaminated food and water; fecal-oral route in children
113
How is Giardiasis diagnosed?
ELISA testing, PCR testing
114
What drugs can be used to treat Giardiasis?
Tinidazole, nitazoxanide
115
What is Entamoeba histolytica?
a pathogenic amoeba with a single large nucleus and a prominent nucleolus termed a karyosome
116
What are the symptoms of Entamoeba histolytica?
dysentery, abdominal pain, fever, diarrhea, weight loss, hemorrhage, perforation, appendicitis, ameboma growths
117
How is Entamoeba histolytica transmitted?
Contaminated food and drink
118
How is Entamoeba histolytica diagnosed?
ELISA and PCR testing
119
What drugs are used to treat Entamoeba histolytica?
metronidazole, chloroquine, dehydroemitine
120
What is hepatitis?
inflammatory disease marked by necrosis of hepatocytes and a response by mononuclear WBCs that swells and disrupts liver architecture
121
What are the characteristics of Hepatitis A virus?
nonenveloped, single-stranded RNA, Picornaviridae family, milder and shorter disease
122
How is Hepatitis A transmitted?
Fecal-oral route
123
How is Hepatitis A diagnosed?
detection of anti-HAV antibodies; HA antigen tests
124
How is Hepatitis A prevented?
Immunization
125
What are the characteristics of Hepatitis B virus?
enveloped DNA virus in family Hepadnaviridae; genome is partly double-stranded and partly single-stranded
126
What are the symptoms of Hepatitis B?
fever, chills, malaise, anorexia, abdominal discomfort, diarrhea, nausea, rash, arthritis
127
What is hepatocellular carcinoma?
liver cancer associated with HBV infection
128
How is Hepatitis B diagnosed?
Serological tests, ELISA testing
129
How is HBV prevented?
Immunization
130
What are the characteristics of the Hepatitis C virus?
RNA virus in the Flaviviridae family; most common cause of liver transplants in the US
131
How is HCV diagnosed?
blood test for antibodies to the virus
132
How is HCV transmitted?
sanctioned and unsanctioned blood contact
133
How are most helminth infections diagnosed?
differential blood count showing eosinophilia and serological tests indicating sensitivity to helminth antigens; discovery of helminth eggs, larvae, or adults in feces or tissues
134
What are the characteristics of Enterobius vermicularis?
nematode; called pinworm or threadworm, transmission through cycle A
135
What are the symptoms of Enterobius vermicularis?
anal itching, disrupted sleep, nausea, abdominal discomfort, diarrhea
136
What are the characteristics of Trichuris trichuria?
nematode, whipworm, transmission through cycle A
137
What are the symptoms of Trichuris trichuria?
localized hemmorhage of the bowel, dysentery, loss of muscle tone, rectal prolapse
138
What are the characteristics of Diphyllobothrium latum?
tapeworm, intermediate host in fish
139
What are the symptoms of Diphyllobothrium latum?
abdominal discomfort, nausea, anemia
140
What are the characteristics of Hymenolepis species?
Tapeworms, follow cycle C, most common human tapeworm species
141
What are the characteristics of Ascaris lumbricoides?
roundworm, exhibit migratory symptoms, follows cycle A
142
What are the characteristics of Taenia solium?
tapeworm, scolex with hooklets and suckers for attachment, often associated with pigs/pork, follows cycle C
143
What is cysticercosis?
condition in which T. solium larvae become embedded in human tissues
144
Which group of worms has an affinity for the liver?
trematodes
145
What are the characteristics of Opisthorchis sinensis and Clonorchis sinensis?
intermediate hosts are snails and fish; follow cycle D; known as Chinese liver flukes
146
What are the symptoms of Fasciola hepatica?
vomiting, diarrhea, hepatomegaly, bile obstruction
147
What is trichinosis?
an infection transmitted by eating pork that has nematode Trichinella cysts embedded in the meat
148
What are the symptoms of trichinosis?
diarrhea, nausea, abdominal pains, fever, sweating, puffiness around the eyes, muscle and joint pain, shortness of breath, pronounced eosinophilia
149
What is schistomiasis?
Infection by a blood fluke, often as a result of contact with contaminated water
150
What are the symptoms of schistomiasis?
itchiness at the site where the worm entered the body, fever, chills, diarrhea, cough, hepatomegaly, liver disease, splenomegaly
151
What are the characteristics of schistomes?
trematodes, cylindrical, often called blood flukes, life cycle D
152
How do schistomes evade the immune system?
forming coatings with proteins from the host's bloodstream that "cloak" them from immune cells
153
What is the first stage of a schistome trematode called?
Miracidium
154
What is the second stage of a schistome trematode called?
Cercaria
155
How is schistomiasis diagnosed?
identification of eggs in the urine or feces
156
What is the drug of choice for treating schistomiasis?
praziquantel
