INFECTIOUS DISEASE Flashcards
1
Q
Triad for Weil’s syndrome (3):
A
a. Jaundice
b. Hemorrhagic diathesis
c. Renal dysfunction
2
Q
Coiled, thin, highly motile organisms that have hooked ends and two periplasmic flagella, with polar extrusions from the cytoplasmic membrane that are responsible for motility
A
Leptospira sp.
3
Q
Sex predilection of leptospirosis
A
Men
4
Q
Most important reservoir of leptospirosis
A
Rodents (esp. rats)
5
Q
Leptopirosa serovar associated with rats as reservoir (2):
A
a. Icterohaemorrhagiae
b. Copenhageni
6
Q
Leptopirosa serovar associated with voles as reservoir:
A
Grippotyphosa
7
Q
Leptopirosa serovar associated with cattle as reservoir:
A
Hardjo
8
Q
Leptopirosa serovar associated with dogs as reservoir:
A
Canicola
9
Q
Leptopirosa serovar associated with pigs as reservoir:
A
Pomona
10
Q
Percentage of leptospirosis that lead to severe, potentially fatal complications
A
~1%
11
Q
An independent risk factor for leptospirosis:
A
Swimming in the Segama River
12
Q
Phase of leptospirosis wherein organisms proliferate, cross tissue barriers, and disseminate hematogenously to all organs
A
Leptospiremic phase
13
Q
Phase of leptospirosis when organism can be isolated from the bloodstream
A
Leptospiremic phase
14
Q
During leptospiremic phase, organisms are able to survive in the nonimmune host by evading complement-mediated killing by binding ____:
A
Factor H (a strong inhibitor of the complement system)
15
Q
Phase of leptospirosis where the appearance of antibodies coincides with the disappearance of leptospires from the blood
A
Immune phase
16
Q
Phase of leptospirosis where bacteria persist in various organs, including liver, lung, kidney, heart, and brain
A
Immune phase
17
Q
Deregulation of the expression of several transporters along the nephron in leptospirosis causes these 3:
A
a. Impaired sodium absorption
b. Tubular potassium wasting
c. Polyuria
18
Q
Thrombocytopenia in leptospirosis is most likely due to:
A
Platelet consumption
19
Q
The only leptospiral virulence factor shown to satisfy Koch’s molecular postulates
A
Loa22
20
Q
Hallmarks of fatal leptospirosis (2):
A
a. Bleeding
b. Multiorgan failure
21
Q
Incubation period of leptospirosis:
A
1-2 weeks (may range from 1-30 days)
22
Q
During immune phase, leptospires can be cultured in the:
A
Urine
23
Q
Milder cases of leptospirosis do not always include this phase:
A
Immune phase
24
Q
Mild leptospirosis usually spontaneously resolve within:
A
7–10 days
25
Case–fatality rate of severe leptospirosis:
1 to 50%
26
Risk factor for higher mortality rates in leptospirosis (6):
a. Age >40
b. Altered mental status
c. Acute renal failure
d. Respiratory insufficiency
e. Hypotension
f. Arrhythmias
27
Percentage of patients with leptospirosis who have jaundice:
5-10%
28
Jaundice in leptospirosis is usually associated with fulminant hepatic necrosis: True/False
False
29
Typical electrolyte abnormalities in leptospirosis (2):
a. Hypokalemia
| b. Hyponatremia
30
Unique feature of leptospiral nephropathy
Loss of Mg in the urine
31
Characteristic of renal manifestation of early leptospirosis
Nonoliguric hypokalemic renal insufficiency
32
Most common radiographic finding in Leptospirosis:
Patchy bilateral alveolar pattern (due to scattered alveolar hemorrhage and predominantly affects the lower lobes)
33
Definitive diagnosis of leptospirosis (3):
a. Isolation of organism
b. Positive PCR
c. Seroconversion or a rise in antibody titer
34
Microscopic agglutination test (MAT) result required for diagnosis of leptospirosis in cases with strong clinical evidence of infection:
1:200 – 1:800
35
Has the capacity to confirm the diagnosis of leptospirosis with a high degree of accuracy during the first 5 days of illness
PCR
36
DOC for severe leptospirosis
IV penicillin
37
Alternative drugs for severe leptospirosis (3):
a. Ceftriaxone
b. Cefotaxime
c. Doxycycline
38
Recommended oral drugs for mild leptospirosis (4):
a. Doxycycline
b. Azithromycin
c. Ampicillin
d. Amoxicillin
39
DOC for leptospirosis in areas where rickettsial diseases are coendemic (2):
a. Doxycycline
| b. Azithromycin
40
Rare reaction that occurs within hours after the initiation of antimicrobial therapy in leptospirosis:
Jarisch-Herxheimer reaction
41
Adjunct therapy for pulmonary involvement associated with severe leptospirosis (2)
a. Glucocorticoids
| b. Desmopressin
42
Dose of doxycycline in mild leptospirosis:
100 mg BID x 7 days
43
Dose of Amoxicillin in mild leptospirosis:
500 mg TID x 7 days
44
Dose of ampicillin in mild leptospirosis:
500 mg TID x 7 days
45
Dose of Pen G in moderate/severe leptospirosis:
1.5M u IV or IM q6hrs x 7 days
46
Dose of Ceftriaxone in moderate/severe leptospirosis:
2 g/day IV x 7 days
47
Dose of cefotaxime in moderate/severe leptospirosis:
1g IV q6hrs x 7 days
48
Dose of doxycycline in moderate/severe leptospirosis:
LD 200 mg IV, then 100 mg IV q12h
49
The protypic lesion of IE
Vegetation
50
Analogous process of IE in AV shunts, AA shunts (i.e. PDA) or coarctation of the aorta
Infective endarteritis
51
A hectically febrile illness that rapidly damages cardiac structures, seeds to intracardiac sites
Acute Endocarditis
52
Has indolent course and causes structural cardiac damage only slowly, and rarely metastasizes
Subacute Endocarditis
53
Predisposing factors for IE (4):
Congenital heart disease
Illicit IV drug use
Degenerative valve disease
Intracardiac devices
54
Most common organisms causing IE (3):
Viridans streptococci
Staphylococci
HACEK organisms
55
What are HACEK organisms?
```
Haemophilus species
Aggregatibacter species
Cardiobacterium hominis
Eikenella corrodens
Kingella kingae
```
56
Primary portals for IE (3):
oral cavity
skin
upper respiratory tract
57
Organism from GIT, associated with polyps and colonic tumors, that can cause IE:
Streptococcus gallolyticus subspecies gallolyticus (formerly S. bovis biotype 1)
58
How many percent of IE have negative blood cultures
5-15%
59
Causes an indolent, culture-negative, afebrile form of endocarditis
Tropheryma whipplei
60
Early prosthetic valve endocarditis arises within how many months after valve surgery?
2 months
61
Delayed onset prosthetic valve endocarditis arises within how many months after valve surgery?
2-12 months
62
Late prosthetic valve endocarditis arises within how many months after valve surgery?
>12 months
63
How many percent of coagulase-negative staphylococcus strain causing PVE are resitant to methicillin?
At least 68-85%
64
Most common cause of cardiovascular ICD endocarditis (2):
S. aureus
| CoNS
65
Most commonly affected valve in injection drug-use-associated endocarditis? And the most common cause?
Tricuspid valve, S. aureus
66
Endocarditis with uninfected vegetations seen in patients with malignancy and chronic diseases
Marantic endocarditis
67
Adherence of gram positive bacteria in IE is facilitated by:
Fibronectin-binding proteins
68
Adherence of S. aureus in IE is facilitated by:
Clumping factor
69
Adherence of Enterococcus faecalis in IE is facilitated by (3):
Fibrinogen-binding surface proteins (Fss2)
Collagen-binding surface protein (Ace)
Ebp pili
70
Adherence of streptococcus in IE is facilitated by:
Glucans or FimA
71
Organisms deep in vegetations are metabolically active and relatively susceptible to killing by antimicrobial agents
Inactive, resistant to killing
72
How many % of IE patients will have CHF?
30-40%
73
Cause of CHF in IE (2):
```
Valve dysfunction
Intracardiac fistulae (occasionally)
```
74
How many % of IE patients will have MI?
2%, due to emboli to a coronary artery
75
Classic nonsuppurative peripheral manifestation of IE that is related to prolonged infection
Janeway lesions
76
Arterial emboli in IE is increased in: (3)
S. aureus endocarditis
Mobile vegetations >10 mm in diameter
Infection involving the mitral valve (esp anterior leaflet)
77
How many % of IE patients will have cerebrovascular emboli?
15-35%
78
Endocarditis of which side will more likely cause cerebrovascular emboli?
Left-sided endocarditis
79
Focal dilations of arteries occurring at points in the artery wall that have been weakened by infection in the vasa vasorum or where septic emboli have lodged
Mycotic aneurysms
80
The diagnosis of infective endocarditis is established with certainty only when
vegetations are examined histologically and microbiologically
81
A highly sensitive and specific diagnostic schem for IE
Modified Duke Criteria
82
Clinical diagnosis of definite endocarditis based on Modified Duke Criteria
two major criteria, or one major criterion and three minor criteria, or of five minor criteria
83
Diagnosis of endocarditis is rejected if (3):
Alternative diagnosis is established
Symptoms resolve and do not recur with ≤4 days of antibiotic therapy
Surgery or autopsy after ≤4 days of antimicrobial therapy yields no histologic evidence of endocarditis
84
Possible IE
One major and one minor criterion
| Three minor criteria
85
Modified Duke Critera: Major criteria (2)
Positive blood culture
o Typical microorganism for IE in 2 separate blood culture
o Persistently positive blood culture, defined as recovery of microorganism consistent with IE from blood cultures drawn > 12 h apart, or all of 3 or a majority of >/= 4 separate blood culture with 1st and last drawn at least 1 h apart
o Single positive blood culture for Coxiella burnetti or phase I IgG antibody titer of >1:800
Evidence of endocardial involvement
o Positive echocardiogram
o New valvular regurgitation
86
Positive echochardiogram findings of IE (3):
Oscillating intracardiac mass on valve or supporting structures or in path of regurgitant jets or in implanted material, in the absence of an alternative anatomic explanation
Abscess
New partial dehiscence of prosthetic valve
87
Minor criteria of Modified Duke Criteria (5)
Predisposing heart conditions or injection drug use
Fever≥ 38C
Vascular phenomena
Immunologic phenomena
Microbiologic evidence (positive blood culture not meeting major criteria, or serologic evidence)
88
Vascular phenomenon included in the modified duke criteria (6)
```
Major arterial emboli
Septic pulmonary infarcts
Mycotic aneurysm
Intracranial hemorrhage
Conjunctival hemorrhages
Janeway lesions
```
89
Immunologic phenomena included in the modified duke criteria (4)
Glomerulonephritis
Osler’s nodes
Roth’s spots
Rheumatoid factor
90
How to obtain blood cultures for IE?
Three 2-bottle blood culture sets, separated from one another by at least 2 h, should be obtained from different venipuncture sites over 24 h
91
Treatment of Candida endocarditis
Amphotericin B (3–5 mg/kg IV qd) plus flucytosine (25 mg/kg PO q6h)
92
Empirical therapy for culture-negative endocarditis injection drug user or health care-assocaited NVE
Vancomycin plus gentamicin or cefepime
93
Empirical therapy for NVE with subacute presentation
Vancomycin plus ceftriaxone
94
Empirical therapy for blood culture-pending PVE
Vancomyci, gentamicin and cefepime if prothetic valve has been in place for ≤1 year
Similar to NVE if prosthetic valves in place for >1 year
95
Duration of antibiotic therapy if with CIED endocarditis and bacteremia that persist even after removal
4- to 6-week course
96
Duration of antibiotic therapy for generator pocket infection without bacteremia
10- to 14-day course
97
Anticoagulation must be given for IE. True or false
False. Patients with IE are at risk for emboli, for hemorrhagic transformation of embolic strokes, and for intracerebral hemorrhage from septic arteritis or ruptured mycotic aneurysms
98
The most common indications for surgery in IE (2)
Intracardiac complications
| CHF
99
Indications of surgery in IE (5):
```
Congestive Heart Failure
Perivalvular Infection
Uncontrolled Infection
Prevention of Septic emboli
CIED Endocarditis
```
100
Most commonly affected valve in the perivalvular infection complication of IE
Aortic valve
101
Test of choice to detect perivalvular abscesses
TEE with color Doppler
102
In CIED endocarditis, when can you reimplant CIED if necessary?
At a new site 10-14 days of antimicrobial therapy
103
If surgical indication is not urgent, cardiac surgery should be delayed for _______ after a large nonhemorrhagic embolic infarction and ______ after a cerebral hemorrhage
2-3 weeks
| 4 weeks
104
Extracardiac complications of IE (2):
Splenic abscess
| Mycotic aneurysm
105
Salmonella sp. that are restricted to human hosts, causing enteric (typhoid) fever (2)
Salmonella typhi and paratyphi
106
Salmonella:
Gram negative or positive?
Spore forming or not?
Aerobe or unaerobe?
Gram negative bacilli, non-spore-forming, facultatively anaerobic bacilli
107
Family of Salmonella
Enterobacteriaceae
108
Salmonella produce what gas on sugar fermentation? Salmonella that does not form this gas?
H2S
| Salmonella typhi
109
Serogroup of salmonella that cause ~99% of infections in humans and other warm-blooded animals
O-antigen serogroups
110
Infectious dose of salmonella
200 CFU to 106 CFU
111
Characterized by infiltration of mononuclear cells into the small bowel mucosa
Enteric fever
112
infectous disease that is characterized by massive PMN leukocyte infiltration into both the large and small bowel mucosa
NTS gastroenteritis
113
Etiologic agents of enteric fever
S. Typhi and S. Paratyphi serotypes A, B and C
114
Incubation period of enteric fever
average of 10-14 days but ranges from 5-21 days
115
Which is milder, S. parathyphi or typhi?
Paratyphi
116
Rash of typhoid fever and found in how any percentage?
Rose spots – 30%
117
Faint, salmon-colored, blanching, maculopapular rash primarily in the trunk and chest, and evident at the end of the 1st week of typhoid fever
Rose spots
118
ECG findings in typhoid fever seen in <50% of cases
Relative bradycardia at the peak of high fever
119
Disease that has neuropsychiatric symptoms of “muttering delirium” or “coma vigil”, and picking at bedclothes or imaginary objects
Typhoid fever
120
Up to ____ of untreated salmonellosis will excrete S. Typhi in the feces for up ______, and _____ will be a chronic carrier up to ____.
10% - 3 months
| 2-5% - >1 year
121
Concomittant infection with this organism is a risk factor for chronic asymptomatic carriage of Salmonella
S. haematobium
122
Chronic asymptomatic carriage of salmonella will increase risk of what cancer
Gallbladder CA
123
In salmonellosis, if blood, bone marrow, and intestinal secretions are all cultured, the yield is
>90%
124
Serologic test for typhoid fever for febrile agglutinins
Widal serologic tests
125
Most effective class of agents for drug-susceptible typhoid fever
Fluoroquinolones
126
Preferred fluoroquinolones for typhoid fever
Ciprofloxacin
127
Treatment for DSC Typhoid fever (3)
Ceftriaxone
Azithromycin
High dose ciprofloxacin
128
Treatment for MDR salmonellosis
Ceftriaxone
Cefotaxime
Cefixime
129
Treatment of complicated enteric fever and duration of treatment
IV 3rd gen cephalosporin or fluoroquinolone up to at least 10 days or for 5 days after fever resolution
130
Glucocorticoid used for enteric fever (include dose and indication)
Dexamethasone initial dose of 3 mg/kg then 8 doses of 1 mg/kg every 6 h
severe enteric fever
131
Treatment of chronic salmonella carriage and duration of treatment
Oral ciprofloxacin or other fluoroquinolones x 4 weeks
132
2 typhoid vaccines
Ty21a – oral live attenuated S. Typhi vaccine
| Vi CPS – parenteral vaccine consisting of purified Vi polysaccharide from the bacterial capsule
133
DOC for MDR – nontyphoidal salmonellosis (2)
extended spectrum cephalosporins and fluoroquinolones
134
An illness that mimics inflammatory bowel disease that is seen in NT salmonellosis
Pseudoappendicitis
135
Antibiotics is not usually recommended in NT salmonellosis. Why?
may prolong fecal carriage
136
Bacteremia is most common in what organism causing NTS (2)?
Salmonella Choleraesuis and Salmonella Dublin
137
Suspected in elderly patients with prolonged fever and back, chest or abdominal pain developing after an episode of gastroenteritis
NTS Arteritis
138
Preemptive antibiotic treatment for NTS is given only to these populations (6)
* Neonates (up to 3 mos of age)
* > 50 years of age
* Athersosclerosis
* Immunosuppressed
* Cardiac valvular or endovascular abnormalities
* Significant joint disease
139
Treatment for NTS endocarditis and arteritis with duration:
* 6 weeks IV β-lactam antyibiotic (ceftriaxone or ampicillin)
* May also be given with IV ciprofloxacin
140
2 forms of Rabies
* Encephalitic
| * Paralytic
141
Genus of rabies virus
Lyssavirus
142
Rabies virus is what kind of virus? DNA or RNA?
Single-stranded RNA virus, nonsegmented
143
Incubation period of rabies
20-90 days
144
In muscles, rabies bind to what receptor?
nicotinic Acetylcholine receptor on postsynaptic membranes at NMJ
145
Rabies virus spread centripetally along peripheral nerves toward the spinal cord or brainstem via _______. Virus then enters the CNS and rapidly disseminates to other regions of the CNS via ______ along neuroanatomic connections
retrograde fast axonal transport
| fast axonal transport
146
T or F: Rabies virus prominently infect astrocytes
False. Neurons. Astrocytes infection is unusual
147
Pathologic changes in rabies include mononuclear inflammatory infiltration in the leptomeninges, perivascular regions, and parenchyma, including the microglial nodules called
Babes nodules
148
Most characteristic pathologic finding in rabies
Negri bodies
149
Eosinophilic cytoplasmic inclusions in brain neurons composed of rabies virus proteins and viral RNA
Negri bodies
150
T or F: neuronal death is responsible for the clinical disease in rabies
False. Neuronal dysfunction
151
Earliest specific neurologic symptoms that strongly suggest rabies (3):
* Paresthesias near the site of the exposure
* Pain near the site of the exposure
* Pruritus near the site of the exposure
152
Encephalitic (furious) form and paralytic form are seen in how many percent of rabies patients respectively
80%
| 20%
153
T or F: Episodes of hyperexcitability in rabies are typically followed by periods of complete lucidity that become shorter as the disease progresses
True
154
Early brainstem involvement in rabies present as
Hydrophobia
| Aerophobia
155
T or F: Paralytic forms of rabies generally survive a few days shorter than those with encephalitic rabies
False. Longer.
156
Highly sensitive and specific test for rabies (2)
RT-PCR
| Direct fluorescent antibody (DFA) testing (can be performed quickly)
157
Difference between rabies encephalitis and other acute encephalitis
Early brainstem involvement with preservation of consciousness
158
T or F: rabies has 100% mortality rate
False. Aggressive management with supportive care in critical care units has resulted in the survival of more than 15 patients with rabies. But is an almost uniformly fatal disease.
159
T or F: Rabies is nearly always preventable after recognized exposures with appropriate postexposure therapy during the early incubation period
True
160
Active immunization of rabies
Four 1 mL doses of rabies vaccine given IM in the deltoid area or anterolateral aspect of the thigh (children) at day 0, 3, 7, 14 (5th dose on Day 28 no longer recommended)
161
T or F: Rabies vaccine is contraindicated in pregnancy
False
162
Who should receive the passive immunization of rabies?
To all previously unvaccinated persons
163
When should rabies Ig be administered
Should be administered within 7 days after the 1st vaccine dose
164
Dose of Rabies Ig
20 iu/kg, or 40iu/kg (purified ERIG) infiltrated at the site of bite then the remaining dose given IM at distant site; If exposure is through mucous membrane, entire dose must be given as IM
165
T or F: Rabies Ig may be given at the same site as the vaccine
False. Not same site
166
Preexposure rabies vaccination is given at how many doses?
3 doses. Day 0, 7, and 21 or 28
167
When a previously immunized individual is exposed to rabies, when will you give booster dose?
2 doses. Day 0 and 3.
168
most common and frequent infections in humans
Respiratory virus infection
169
mark the transition between the upper and lower respiratory tracts
Vocal cords
170
Parts of lower respiratory tract (5)
* Trachea
* Bronchi
* Bronchioles
* Alveolar spaces
* Lung tissue
```
Upper respiratory tract
• Sinuses
• Middle-ear spaces
• Eustachian tubes
• Conjunctiva
• Nasopharynx
• Oropharynx
• Larynx
```
171
Principal types of cells in the major airways (3)
* Cilated or nonciliated epithelial cells
* Goblet cells
* Clara cells
172
Wheezing is the constriction of lumen size of smooth muscles at the level of
Bronchioles
173
With narrowest lumen diameter of the airways
Bronchioles
174
Difficulty in inspiration associated with barky cough
Croup
Inflammation or infection of the larynx, trachea, and bronchi
175
Most common viral causes of serious lower respiratory tract disease (3)
* Influenza viruses
* RSV
* Human metapneumovirus
176
Most common cause of common colds
Rhinoviruses
177
Most common virus isolated in immunosuppressed patients with pneumonia during bronchoalveolar lavage
Cytomegalovirus
178
Influenza virus belong to what family?
Orthomyxoviridae
179
Influenza infection has high rate of complication with bacterial superinfection, most commonly with (2)
S. aureus and S. pneumoniae
180
Describe influenza virus
A single-stranded, segmented, negative-sense, RNA genome virus
181
Influenza virus that is most virulent for humans
Influenza A
182
Influenza that is composed of hemagglutinins and neuraminidase
Influenza A
183
Influenza that infect humans almost exclusively
Influenza B
184
A process that can make the zoonotic viruses (e.g avian or swine) more fit for replications in humans
Reassortment
185
RSV is from what genus and family?
Genus: Pneumovirus
Family: paramyxoviridae
186
Single-stranded, negative-sense, non-segmented, RNA virus that is one of the most common viral causes of severe lower respiratory tract illness in the elderly and in children
RSV
187
Infection with this virus early in life have strong association with subsequent asthma
RSV
188
Measles virus is from what genus and family?
Genus: Morbilivirus
Family: paramyxoviridae
189
Most contagious respiratory virus infection of humans
Measles virus
190
Clinical manifestations of measles (4)
* ≥ 3 days of high fever
* 3 Cs: cough, coryza and conjunctivitis
* Diffuse maculopapular rash appears within days of fever onset
* Koplik’s spots
191
Typical mucosal lesions in the mouth that appear briefly in measles
Koplik’s spots
192
Coxsackievirus belong to what family?
Picornaviridae
Enterovirus A
193
Causes hand-foot-and-mouth disease and herpangina
Coxsackievirus
194
Clinical syndrome of ulcers or small vesicles on the palate that often involves the tonsillar fossa associated with fever, difficulty swallowing, and throat pain
Herpangina
195
Clinical manifestation of epidemic pleurodynia
Acute illness characterized by sharp chest pain and fever
196
Epidemic herpangina is caused by
Echovirus 11
197
Describe structure of rhinovirus
Single-stranded, positive-sense RNA virus
| Icosahedral and non-enveloped
198
Describe structure of adenovirus
Double-stranded DNA virus, non-segmented, <100 nm in diameter, non-enveloped, icosahedral morphology
199
Common in stressful or crowded living conditions and was first recognized among military recruits during WWII
Adenovirus
Most often associated with adenovirus types 4 and 7
200
When was the epidemic of SARS-CoV
Nov 2002 to July 2003
201
Mortality rate of SARS-CoV
10%
202
Mortality rate of MERS-Cov
35%
203
MERS-CoV may have emerged from what animals?
Bats
204
Herpes that mostly affects the oral cavity
HSV-1
205
Describe the structure of polyomaviruses
Small, double-stranded, DNA viruses, non-enveloped, icosahedral
206
Respiratory virus that may be oncogenic
Polyomavirus
207
Polyomavirus that can infect the respiratory system, kidney, or brain
JC virus
208
Polyomavirus that causes mild respiratory infection or pneumonia
BK virus
209
Major determinant of risk for symptomatic disease during respiratory virus infection
Age
210
T or F: Primary infection of respiratory virus is usually more severe than reinfection
True
211
Gold standard for diagnosing a respiratory viral infection
Virus isolation
212
Most sensitive and specific test for respiratory viral infection
RT-PCR
213
Neuraminidase inhibitors act on what influenza type
A and B
214
Neuraminidase inhibitors
Oseltamivir
Zanamivir
Peramivir
Laninamivir
215
Neuraminidase inhibitors that may cause bronchospasm in asthma and COPD
Zanamivir
216
Adamantanes are used for treatment of what influenza?
Influenza A
217
Nucleoside antimetabolite prodrug that is used as treatment for RSV infection
Ribavirin
218
Caused by point mutations in the H and N molecules of influenza
Antigenic drift
219
This is the reason why there is a need to produce new vaccines yearly
Antigenic drift
220
Reassortment of 2 viruses during co-infection of one individual or animal that may cause a pandemic
Antigenic shift
221
Most common cause of contact transmission of viruses
Poor hand hygiene
222
The basic level of infection control that is used in the care of all patients at all times
Standard precaution
223
The second level of infection control that is used and may require a single room for the patient when possible
Contact precaution
224
Range of large-particle droplets during transmission of virus
3 ft
225
T or F. Acute bacterial infection of joints typically involve multiple joints
False. single or a few joints only
226
Immunologic reaction of joints during course of endocarditis, rheumatic fever, disseminated neisserial infection, and acute hepatitis B
Acute polyarticular arthritis
227
Cell count in normal synovial fluid
<180 cells per microliter
228
Predominant cell in normal synovial fluid
mononuclear
229
Cell count in synovial fluid during acute bacterial infection
Cell count of 25,000 – 250,000/uL
>90% neutrophils
230
Cell count in synovial fluid of crystal-induced, rheumatoid, and noninfectious inflammation
<30,000-50,000/uL
231
Cell count in synovial fluid during mycobacterial and fungal infection
10,000 – 30,000/uL
50-70% neutrophils and the remainder lymphocytes
232
Mode of transmission of acute bacterial arthritis
o Hematogenous infection
| o Direct inoculation
233
Most mode of transmission of acute bacterial arthritis
Hematogenous route
234
Most common bacteria isolated in acute bacterial arthritis in young adults and adolescents
N. gonorrheae
235
Most common nongonococcal bacteria isolated in acute bacterial arthritis in adults
S. aureus
236
Most common bacteria isolated in acute bacterial arthritis that is post-surgical or trauma-induced
S. aureus
237
Penetration of a sharp object through a shoe will cause an arthritis in the foot caused by what organism
Pseudomonas aeruginosa
238
Highest incidence of infective arthritis occurs in patients with
Rheumatoid arthritis
239
Most common cause of infectious arthritis among patients with rheumatoid arthritis
S. aureus
240
Infectious arthritis that is most often seen in primary iimmunoglobulin deficiency
Mycoplasmal arthritis
241
treatment of mycoplasmal arthritis (2)
tetracycline and IV immunoglobulin
242
Most commonly involved joint in the acute bacterial arthritis
Knee
243
Most commonly involved joints in the acute bacterial arthritis among IV drug users (3)
Spine, sacroiliac joints, and sternoclavicular joints
244
On plain radiograph, this indicates advanced infection with poor prognosis
Narrowing of the joint space and bony erosions
245
T or F: Men are more likely to develop disseminated gonococcal infection (DGI) and arthritis than women
False. Women are more likely, especially during menses and pregnancy
246
Small number of papules that progress to hemorrhagic pustules in the trunk and extensor surfaces of the distal extremities associated with migratory arthritis and tenoxynovitis of the knees, hands, wrists, feet and ankles
Disseminated Gonococcal Infection
247
T or F. In true gonococcal septic arthritis, blood culture is almost always negative
True
248
Agar used to isolate organism in gonococcal arthritis
Thayer-Martin agar
249
This supports a clinical diagnosis of the disseminated gonococcal syndrome if cultures are negative
Dramatic alleviation of symptoms within 12-24 h after the initiation of appropriate antibiotic therapy
250
Treatment for gonococcal arthritis
Ceftriaxone 1g IV or IM every 24 h
Once local and systemic signs are clearly resolving, 7-day course of therapy can be completed with an oral fluoroquinolone such as ciprofloxacin 500 mg BID and Amoxicillin 500 mg TID
251
Aside from treating the gonococcal arthritis with ceftriaxone or ciprofloxaciin, what other antibiotic will you give and for what reason?
Azithromycin 1g single dose
they should be treated for Chlamydia trachomatis infection also
252
Cause of lyme disease
Borrelia burgdorferi
253
Lyme diseaseis transmitted by
Ixodes tick
254
Antibiotic treatment of lyme disease (3)
Oral doxycycline 100 mg BID for 28 days
Oral amoxicillin 500 mg TID for 28 days
IV ceftriaxone 2g/day for 2-4 weeks
255
Periarticular swelling and immobilization of the involved limbs complicate osteochondritis of long bones in congenital syphilis
Parrot’s pseudoparalysis
256
Late joint manifestation of congenital syphilis caused by painless synovitis with effusions of large joints
Clutton’s joint
257
Joint deformity that result from sensory loss due to tabes dorsalis
Charcot joint
in tertiary syphilis
258
Most common presentation of mycobacterial arthritis
Chronic granulomatous monoarthritis
259
Unusual syndrome which is a reactive symmetric form of polyarthritis that affects persons with visceral or disseminated tuberculosis
Poncet’s disease
260
Most common cause of fungal arthritis (3)
Coccidioids immitis
Blastomyces dermatitidis
Histoplasma capsulatum
261
Treatment of fungal arthritis
amphotericin (IV and intraarticular)
262
T or F. In management of infections of prosthetic joints, prosthesis must be always replaced
False.
Prosthesis may not be removed if:
o In cases of streptococci or pneumococci
o Lack of radiologic evidence of loosening of the prosthesis
o Antibiotic therapy must be initiated within several days of the onset of infection
o Joint should be drained vigorously by open arthrotomy or arthroscopically
263
Therapy that has a high cure rate with retention of prosthesis in infections of prosthetic joints
Oral rifampin plus another antibiotic
264
Trematodes are also known as
flatworms
265
Trematodes belong to what phylum?
Platyhelminthes
266
All the trematodes are hermophriditic except for
Shistosomes
267
Definitive host of trematodes
mammal / humans
268
Infective stage of Schistosoma
Cercariae
269
Cercariae of the schistosomes penetrate intact human skin within a few minutes after attaching to the skin then transform to
shistosomula
270
Where does the schisosomes mature to adult males and females
portal vein
271
Final location of adult schistosomes (2)
mesenteric or pelvic venous plexus
272
Interval from schistosome cercarial penetration to sexual maturation and egg production
Prepatent period
5-7 weeks
273
Free-swimming larval stage of schistosomes
miracidium
274
Life cycle of schistosomes that penetrate the host snail then undergoes asexual multiplication
miracidium
275
The only stage of the schistosome that is detected in humans
egg
276
Schistosome egg that has terminal spine
S. haematobium eggs
277
Schistosome egg that has lateral spine
S. mansoni eggs
278
Schistosome egg that is smaller, rounder, with a small lateral spine or knob
S. japonicum eggs
279
Body forms a groove or gynecophoric canal in which the mature adult female is held
Male schistosome
280
Compared to male schistosome, female worm is
Longer, thinner, and rounded
281
Humans are the most important definitive hosts for these schistosomes (3)
S. mansoni,
S. haematobium,
S. intercalatum
282
Zoonotic schistosomes
S. japonicum and S. mekongi
283
The most important of the neglected tropical diseases and is second only to malaria in public health impact
• Schistosomiasis
284
T or F: Most manifestations of schistosomiasis are due to immunologic reactions to worms retained in host tissues
False. Eggs
Egg, and not the adult worms, induce the organ-specific morbidity
285
Schistosome species that cause hepatosplenomegaly (2)
S. mansoni
| S. japonicum
286
Schistosome egg-induced granulomatous response leads to this severe periportal fibrosis
Symmers clay pipestem fibrosis
287
S. haematobium has predilection to what veins
urogenital plexus
288
This schistosome can cause intense egg-induced tissue inflammation leading to bladder wall thickening and development of masses and pseudopolyps
S. haematobium
289
Swimmer's itch is caused by
Schistosomes
290
Cause of swimmer's itch
cercarial penetration of the skin
291
causes severe form of cercarial dermatitis
Avian schistosomes
Cannot complete development in humans and die in the skin leading to inflammatory allergic reaction
292
Treatment of cercarial dermatitis
Systemic or topical antihistamines or glucocorticoids
to reduce symptom only
293
Acute schistosomiasis is also known as
Katayama fever
294
Onset of katayama fever is how many weeks/months after exposure?
2 weeks to 3 months
295
Symptoms of Katayama fever (6)
```
o Fever
o Myalgia
o General malaise and fatigue
o Headache
o Nonproductive cough
o Abdominal tenderness or pain
```
296
Liver is enlarged (especially the left lobe) smooth, and firm with no hepatic fibrosis on USD is manifestation of what infection?
Hepatosplenic Schistosomiasis
Early inflammatory hepatosplenomegaly
297
Left hypochondrial mass with discomfort and anorexia, and with USD of typical periportal fibrosis and dilation of the portal vein is manifestation of what infection?
Hepatosplenic schistosomiasis
Late hepatosplenic disease with periportal or Symmers fibrosis
298
Most severe complication of hepatosplenic schistosomiasis
hematemesis
299
Characteristic sign of active stage of urogenital schistosomiasis
Painless, terminal hematuria
300
Manifests as nocturia, urinary retention, dribbling, and incontinence, and with cystoscopic findings of "sandy patches"
Chronic stage of urogenital schistosomiasis
301
Schistosome that is classified as definitely carcinogenic to humans (group 1 carcinogen) and what cancer does to cause?
S. haematobium
May cause squamous cell carcinoma of the urinary bladder
302
Schistosomes that can end up in the spinal venous plexus (2) and the condition that they cause
S. mansoni and S. haematobium
transverse myelitis
303
Schistosome that causes granulomatous lesions in the brain
S. japonicum
304
Rectal biopsies can detect what schistosomes (2)
S. mansoni and S. haematobium
305
Serology that is used by CDC to detect schistosomiasis
Falcon assay screening test / enzyme-linked immunosorbent assay (FAST-ELISA)
Use S. mansoni adult microsomal antigen
306
Drug of choice for all forms of schistosomiasis
Praziquantel
307
Cornerstone of management and control
Praziquantel mass administration programs
308
Most important liver flukes causing human infections (4)
o Opistorchis viverrini and Opistorchis felineus
o Clonorchis sinensis
o Fasciola hepatica
o Fasciola gigantica
309
1st and 2nd intermediate hose of opistorchiasis and clonorchiasis
host snail
| fresh water fish
310
Infective stage of opistorchiasis and clonorchiasis
metacercariae
311
Tretamatodes that may cause cholangiocarcinoma
Opistorchiasis
| Clorchis sinensis
312
2nd intermediate host of Fasciola hepatica
None
metacercariae adhere directly to aquatic plans such as watercress
313
Intestinal fluke
Fasciolopsis buski
314
Lung fluke
Paragonimus westermani
315
2 intermediates host of paragonimus
o Freshwater snail
| o Freshwater crustacean
316
Infective stage of paragonimus westermani
metacercariae
317
2 DOC for trematode infection
o Praziquantel
| o Triclabendazole
318
Based on RITM guidelines, what is Stage I, II and III of tetanus based on incubation period
I - > 14 days
II - > 10-14 days
III - <10 days
319
Based on RITM guidelines, what is Stage I, II and III of tetanus based on period of onset
I - > 6 days
II - > 3-6 days
III - <3 days
320
Based on RITM guidelines, what is Stage I, II and III of tetanus based on trismus
I - mild
II - moderate
III - severe
321
An acute illness with muscle spasms or hypertonia in the absence of a more likely diagnosis than tetanus
Probable tetanus
322
an illness occurring in a child who has the normal ability to suck and cry in the first 2 days of life but who loses this ability between days 3 and 28 of life and becomes rigid and has spasms
Neonatal tetanus
323
Maternal tetanus occus during pregnancy or within _____ after the conclusion of pregnancy (whether with birth, miscarriage, or abortion) – WHO
6 weeks
324
Describe C. tetani in terms of:
aerobic vs anaerobic
gram + vs -
spore-forming vs non-spore-forming
coccus vs bacilli
an anaerobic, gram-positive, spore-forming rod whose spores are highly resilient and can survive readily in the environment throughout the world
325
In______% of cases of tetanus, no puncture entry wound is found.
20–30%
326
the most common infection sites of tetanus in adults
Superficial abrasions to the limbs
327
Difference between tetanospasmin and botulinum toxin in terms of transport to CNS
Tetanospasmin undergoes retrograde transport into the CNS (unlike the botulinum toxin) and thus produces clinical effects different from the botulinum toxin
Botulinum toxins remain at the NMJ
328
Aim of management of tetanus infection (2)
o Neutralize remaining unbound toxin
| o Support vital functions
329
In generalized tetatnus,, which part is affected first most often?
muscles of the face and jaw
330
Milder form of tetanus
Localized tetanus
331
Difference between incubation period and period of onset in tetanus
o Incubation period – time from wound to first symptom
| o Period of onset – time from first symptom to first generalized spasm
332
T or F. In tetanus, shorter incubation period and/or period of onset has worse outcome
True
333
The most common cause of death in tetanus without ventilatory support
Respiratory failure
334
Labile BP with rapid fluctuations from high to low accompanied by tachycardia in tetanus is caused by
autonomic dysfunction
335
Aside from labile BP, autonomic involvement of tetanus is evidenced by (4)
Gastrointestinal stasis
Sweating
Increased tracheal secretions
Acute (often high-output) renal failure
336
Level of serum anti-tetanus IgG (measured by standard ELISA) that is protective and do not support the diagnosis of tetanus
>0.1 IU/mL
337
Preferred antibiotic therapy for tetanus (with dose)
Metronidazole 400 mg rectally or 500 mg IV every 6 h for 7 days
338
Alternative antibiotic for tetanus (with dose)
Penicillin 100,000–200,000 IU/kg per day
339
Theoretically, this drug may exacerbate spasms and in one study was associated with increased mortality in tetanus
Penicillin
340
Preparation of choice of tetanus antitoxin (with dose)
Human tetanus immune globulin (TIG)
Single IM dose (3000–5000 IU) is given with a portion injected around the wound
341
Dose of equine antitoxin for tetanus
10,000–20,000 U is administered IM as a single dose or as divided doses
342
These drugs used in tetanus to control spasm by sedation (2)
Benzodiazepines
| Propofol infusion
343
T or F: In treating the cardiovascular instability in tetanus, long-acting drug are preferred
False. Short-acting drugs that allow rapid titration are preferred.
Longer-acting drugs such as β antagonists may cause hypotensive cardiac arrest
344
Recovery from tetanus may take up to
4–6 weeks
345
How do you give the “Catch-up” schedules for tetanus vaccination?
3-dose primary course with 4 weeks between doses followed by 2 boosters 6 months apart
346
For persons who have received a complete primary course of tetanus vaccine in childhood but no further boosters, how many doses should you give?
Two doses at least 4 weeks apart are recommended
347
T or F. Patients with incomplete or unknown tetanus vaccination or last booster given > 10 years of earlier must be vaccinated but may not be given with TIG.
False. Must also be given passive immunization with TIG
348
WHO recommendation for prevention of maternal and neonatal tetanus
Administration of two doses of tetanus toxoid at least 4 weeks apart to previously unimmunized pregnant women
In high-risk areas: more intensive approach. All women of childbearing age must receive a primary course along with education on safe delivery and postnatal practices
349
```
Factors associated with a poor prognosis in adult tetanus in terms of:
Age
incubation period
time from onset to admission
entry site
period of onset
heart rate
SBP
spasms
temperatur
```
```
Age >70 years
Incubation period <7 days
Short time from first symptom to admission
Puerperal, IV, postsurgery, burn entry site
Period of onset <48 h
Heart rate >140 beats/min
Systolic blood pressure >140 mmHg
Severe disease or spasms
Temperature >38.5°C
```
350
Vibrio cholerae need ____ bacteria to cause disease
10^5-10^8
351
Produces an adherence protein called colonization factor antigen necessary for colonization of the upper small intestine by the organism prior to production of enterotoxin
Enterotoxigenic E. coli
352
3 exotoxins causing vomiting/diarrhea
Enterotoxins
Cytotoxins
Neurotoxins
353
Prototypical enterotoxin
Cholera toxin
354
Exotoxin that cause watery diarrhea by acting directly on secretory mechanisms in the intestinal mucosa
Enterotoxins
355
Part of cholera toxin that contains the enzymatic activity of the toxin
A subunit
356
Part of cholera toxin that binds holotoxin to the enterocyte surface receptor (GM1)
B subunits
357
Cholera toxin causes diarrhea by
Increasing Cl secretion and decreasing Na absorption causing loss of fluid
358
Exotoxin that cause inflammatory diarrhea
Cytotoxins
Cause destruction of mucosal cells
359
This exotoxin produce syndrome of dysentery, with bloody stools containing inflammatory cells
Cytotoxins
Shigella dysenteriae type 1 and Shiga toxin producing E. coli strains
360
More than 99% of the normal colonic microbiota is made up of
anaerobic bacteria
361
T or F. Neutralization of gastric acid with antacids, PPIs, or H2 blockers increase risk of enteric colonization
True
362
The major mechanism for clearance of bacteria from the proximal small intestine
Normal peristalsis
363
Opiates can cause increased frequency of bacterial overgrowth and infection of the small bowel with enteric pathogens by
Impairing intestinal motility
As well as other antimotility drugs, anatomic abnormalities, or hypomotility states
364
Blood group with increased susceptibility to disease due to V. cholerae, Shigella, E. coli O157, and norovirus
O Blood Group
365
marker of fecal leukocytes
Fecal lactoferrin
366
HUS syndrome follows infection with (3)
Shiga toxin-producing bacteria
| Shigella dysebteriae type 1 and enterohemorrhagic E. coli
367
GBS is commonly associated with what infection Shigella dysebteriae type 1 and enterohemorrhagic E. coli
Campylobacter infection
368
most common travel-related infectious illness
Traveler’s diarrhea
369
Single most important cause of Traveler’s diarrhea
Enterotoxigenic strains of E. coli
Enteroaggregative strain is also common
370
Traveler’s diarrhea that is associated with cruise ship is often caused by
Novovirus
371
Traveler’s diarrhea that is common among hikers and campers who drink from fresh water streams
Giardia lamblia
372
Most common etiologic agent associated with outbreaks of AGE
Novovirus
373
Predominant cause of nosocomial diarrhea among adults
C. difficile
374
Caused more than ½ of cases of significant diarrheal illness in elderly patients in chronic-care institutions
C. difficile
375
Identified as a cause of antibiotic-associated hemorrhagic colitis
Klebsiella oxytoca
376
Most morbidity and mortality from enteric pathogens occurs at what age
< 5 years of age
377
Bacteria that cause disease by enterotoxin elaborated outside the host (2)
S. aureus and B. cereus
378
Incubation period and duration for bacterial disease caused by an enterotoxin elaborated outside the host
1-6 h
| <12 h
379
Outbreaks following picnics where potato salad, mayonnaise, and cream pastries have been served is commonly caused by
Staphylococcal food poisoning
380
2 forms of B. cereus food poisoning
Emetic
| Diarrhea
381
Emetic form of B. cereus food poisoning is mediated by what toxin
staphylococcal type of enterotoxin (shorter incubation)
382
Diarrheal form of B. cereus food poisoning is mediated by what toxin
enterotoxin resembling E. coli heat-labile toxin (longer incubation period)
(8-16 )
383
Heat-resistant spores of this bacteria is found in inadequately cooked meat, poultry, or legumes
Clostridium perfringens
384
T or F. All food poisoning has bacterial cause.
False. Not all food poisoning has bacterial cause.
Other causes:
Capsaicin
Toxins from fish and shellfish
385
Mainstay of treatment of acute infectious diarrheal diseases
Adequate rehydration
386
Per L water of ORS consists (4)
* 2.6 g NaCl
* 2.9 g trisodium citrate
* 1.5 g KCl
* 13.5 g glucose (or 27 g sucrose)
387
T or F. Bloody diarrhea should be treated empirically with an antimicrobial agent
True. fluoroquinolone or macrolide
But, Enterohemorrhagic E. coli should NOT be treated with antimicrobial agents because it will increase by 20-fold the risk for HUS and renal failure
388
Treatment of Campylobacter infection
Macrolide such as erythromycin or azithromycin
389
Enterohemorrhagic E. coli should NOT be treated with antimicrobial agents because it will increase by 20-fold the risk for
HUS and renal failure
390
Malaria is transmitted by the bite of
infected female Anopheles mosquitoes
391
Most important of the parasitic diseases of humans
Malaria
392
Almost all malaria deaths are caused by what sp
falciparum malaria
393
Female anopheles mosquito inoculates this life stage of malaria to humans during blood meal
Sporozoites
394
Asexual reproduction of malaria occurs in
Liver
intrahepatic or preerythrocytic schizogony
395
During asexual reproduction of malaria, sporozoites produce
10,000->30,000 merozoites
396
Stage of malaria that invade the RBC
Merozoites
397
Once at the RBC, the malarial stage is called
Trophozoites
398
When malaria reach densities of__________, symptomatic stage begins
~50/μL of blood (~100 million parasites)
399
Dormant form of malaria parasite
hypnozoites
400
A proportion of intrahepatic forms of these plasmodium sp do not divide immediately but remain inert for a period of 2 weeks to ≥1 year (2)
P. vivax and P. ovale
Hypnozoites - cause of the relapses in these species
401
Blood group antigens that plays an important role in invasion of malaria
Duffy blood group antigens – Fya or Fyb
Duffy-negative FyFy phenotype – generally resistant to P. vivax malaria
402
By the end of the intraerythrocytic life cycle, the plasmodium has consumed 2/3 of the RBC’s hemoglobin and has grown to occupy most of the cell. This is then called
Schizont
403
When plasmodium-infected RBC ruptures, it release
6-30 daughter merozoite
404
Malaria disease in human beings is caused by (2)
- Direct effects of asexual parasite (RBC invasion and destruction)
- Host’s reaction
405
Sexual form of malaria
Gametocytes
406
Life stage of malaria that are ingested by biting female anopheles mosquito
Gametocytes
407
Malarial morphology: usually only ring-form, banana-shaped gametocytes
Falciparum
408
Malarial morphology: irregularly shaped large rings and trophozoites, enlarged erythrocytes and Schuffner’s dots
P. vivax
409
Malarial morphology: infected erythrocytes, enlarged and oval with tufted ends; Schuffner’s dots
P. ovale
410
Malarial morphology: band or rectangular forms of trophozoites
P. malariae
411
Pigment colors of the malarial species
Falciparum – black
Vivax – yellow-brown
Ovale – dark brown
Malariae – brown-black
412
Malaria sp that may have relapse
Vivax and ovale
413
Endemicity of malaria in Hypoendemic, Mesoendemic, Hyperendemic and Holoendemic
* Hypoendemic - <10%
* Mesoendemic – 11-50%
* Hyperendemic – 51-75%
* Holoendemic – >75%
414
Characteristic of malarial transmission seen in hyper- and holoendemic areas
Stable transmission
constant, frequent, year-round infection
415
Characteristic of malarial transmission seen in hypoendemic areas
Unstable tansmission
Transmission is low, erratic, or focal
Full protective immunity is not acquired
Malaria can behave like an epidemic disease
High mortality rates among all age group
416
Principal determinants of epidemiology of malaria (3)
* Number / density of anopheline mosquito
* Human-biting habits of anopheline mosquito
* Longevity of anopheline mosquito
417
Number of sporozoite-positive mosquito bites per person per year is also called
Entomologic inoculation rate
418
Most common measure of malaria transmission
Entomologic inoculation rate
419
Effect of malaria to RBC
Alters the RBC membrane
RBCs become more irregular in shape, more antigenic, and less deformable
420
Processes that are central to pathogenesis of P. falciparum infections (3)
Cytoadherence
Resetting
Agglutination
421
This pathogenetic process of malaria refers to attachment to receptors on venular and capillary endothelium mediated by strain-specific erythrocyte membrane adhesive protein (PfEMP1)
Cytoadherence
422
This pathogenetic process of malaria refers when infected RBCs adhere to uninfected RBCs
Resetting
423
This pathogenetic process of malaria refers when infected RBCs adhere to other parasitized erythrocyte
Agglutination
424
Plasmodium sp with marked predilection for young RBCs (2)
P. vivax and P. ovale
425
Plasmodium sp with predilection to old RBCs
P. malariae
426
Plasmodium sp that can invade RBCs of all ages (2)
P. falciparum
| P. knowlesi
427
Process when spleen removes damaged ring-form malarial parasites
Pitting
Spleen returns the once-infected RBC to the circulation shortened survival
Rupture of schizont – happens to those cells escaping splenic removal
428
This host response to malaria is defined by accelerated removal of both parasitized and uninfected RBCs
Augmented splenic immunologic and filtrative clearance
429
Genetic disorders that confer protection against death from falciparum malaria (5)
* Thalassemias
* Sickle cell disease
* Hemoglobins C and E
* Hereditary ovalocytosis
* G6PD deficiency
430
Reason why thalassemia patients are protected against malarial death
α- thalassemia have frequent malaria in early years of life, hence, protection from severe disease
431
Reason why sickle cell disease patients are protected against malarial death
HbA/S RBCs impair parasite growth at low oxygen tensions
6-fold reduction in the risk from of dying from severe falciparum malaria
432
Reason why hereditary ovalocytosis patients are protected against malarial death
Rigid RBCs resist merozoite invation
433
state of plasmodium infection without illness
Premunition
434
Fever spikes, chills, and rigors at regular intervals is characteristic of
Malaria
Classic malarial paroxysms
435
Generalized seizure occur to this malaria type
falciparum malaria
Herald the development of encephalopathy in cerebral malaria
436
If malaria is appropriately and promptly treated, mortality rate is
< 0.1%
437
Once vital-organ dysfunction occurs or total proportion of RBC infected by malaria increases to ____________, mortality risk rises steeply
> 2% (>10^12 parasites in adult)
438
A characteristic and ominous feature of cerebral malaria caused by falciparum
Coma
Death rate: ~20% among adults and 15% among children
439
Cerebral malaria manifest as what type of encephalopathy
diffuse symmetric encephalopathy
440
Primitive reflexes that are common in cerebral malaria (2)
Bruxism and pout reflex
Other primitive reflexes are absent
441
Hypoglycemia in malaria may be compounded by these antimalarial treatment
Quinine and quinidine
Powerful stimulant of pancreatic insulin, causes hyperinsulinemic hypoglycemia
442
Conditions that compounds acidosis in adults and children with malaria
Renal impairment – adult
| Ketoacidosis – children
443
Best biochemical prognosticators in severe malaria (2)
Serum bicarbonate or lactate
444
Mortality rate of noncardiogenic pulmonary edema in severe malaria
>80%
445
Renal impairment in malaria manifests as
acute tubular necrosis
446
Description of anemia in malaria
Normocytic, normochromic
447
Acute hemolytic anemia with massive hemoglobinuria seen in malaria
Blackwater fever
* Hemoglobinuria may contribute to renal injury
* May be seen in patients with G6PD deficiency
448
Antimalarial treatment that may have sudden hemolysis many days after treatment
Artesunate
Due to synchronous loss of once-parasitized “pitted” RBCs
449
T or F: Pregnant mothers in areas with stable malarial transmission are prone to severe infections
False.
In areas with stable transmission, pregnant mothers remain asymptomatic despite intense accumulation of parasitized erythrocytes in the placental microcirculation
In areas with unstable transmission, pregnant women are prone to severe infections
450
T or F. Incubation period of transfusion malaria is longer
False. Incubation period is short – because there is no preerythrocytic stage
451
Clinical features of hyperreactive malarial splenomegaly (3)
* Abdominal mass
* Dragging sensation in the abdomen
* Perisplenitis
452
Chronic or repeated infections with P. malariae (or other malarial species) may cause soluble immune complex injury to the renal glomeruli leading to nephrotic syndrome. This condition is called
Quartan malarial nephropathy
453
Histology of quartan malarial nephropathy (2)
Focal or segmental glomerulonephritis
| Splitting of capillary basement membrane
454
Diagnosis of malaria is obtained by
demonstration of asexual forms of parasite in stained PBS
455
Preferred Romanowsky stains used in malaria detection
Giemsa at pH 7.2
Other stains:
• Field’s
• Wright’s
• Leishman’s
456
Diagnostic stain of malaria that is fixed and density of parasitemia is expressed by number of parasitized RBC per 1000 RBCs
Thin blood smears
457
Diagnostic stain of malaria that is not fixed and number of parasites per unit volume is calculated from the total leukocyte count then converted to number of parasitized RBCs per microliter
Thick blood smear
458
First-line treatment for uncomplicated falciparum malaria in malaria-endemic areas
Artemisinin-based combination therapy (ACT)
459
Remains an effective treatment for P. vivax, P. ovale, and P. malariae
Chloroquine
460
Tinnitus, high-tone hearing loss, nausea, vomiting, dysphoria, postural hypotension are manifestations of this ADR of antimalarial drugs. What is this ADR and what are the antimalarial drugs that may cause it?
cinchonism
| Quinine and quinidine
461
Antimalarial drug that has the ADR of agranulocytosis and hepatotoxicity
Amodiaquine
462
Antimalarial drug that is contraindicated in G6PD patients
Primaquine
May actually be used by with lower dose
463
Antimalarial drug that eradicates hepatic forms of P. vivax and P. ovale; kills all stages of P. falciparum gametocyte development; kills developing liver stages of all species
Primaquine
464
Drug of choice for all patients with severe malaria
Parenteral artesunate
If unavailable, may use artemether, quinine or quinidine
465
T or F. Fluid management of malaria is similar to that of sepsis
False.
Fluid boluses are potentially dangerous un severe malaria
466
In severe malaria, this antimalarial drug must be avoided because it can increase risk of post-malaria neurologic syndrome
Mefloquine
467
Artemisinin derivatives (3)
* Artesunate
* Artemether
* Dihydroartemisinin
468
Used for radical treatment of malaria
Primaquine
469
Antimalarial drug that has adverse neuropsychiatric reaction
Mefloquine
470
These antimalarial drugs exacerbate the orthostatic hypotension associated with malaria
Quinolines (chloroquine, mefloquine, and quinine)
471
If the level of malarialparasitemia does not fall below ___ of the admission value in 72 h or if parasitemia has not cleared by____, drug resistance is likely and the regimen should be changed
25%
| 7 days
472
Treatment of acute renal failure in malaria
Renal replacement therapy
Hemofiltration or hemodialysis
473
Suspected when condition of any patient suddenly deteriorates for no obvious reason during antimalarial treatment
Sepsis
474
Used in mass treatment of malaria for focal elimination of falciparum malaria
slowly eliminated antimalarials such as dihydroartemisinin-piperaquine
475
Peak feeding times of anopheles
dusk to dawn
476
Chemoprophylaxis for malaria (3).
Atovaquone-proguanil (Malarone)
Doxycycline
Mefloquine
Other drugs may also be used
477
Once-daily chemoprophylaxis for malaria that is effective in ALL types of malaria including MDR falciparum malaria
Atovaquone-proguanil (Malarone)
478
Only drug advised for pregnant women traveling to areas with drug-resistant malaria
Mefloquine
* Choloroquine and proguanil – safe, but recommended in very few regions only
* Doxycycline – safe until 15 weeks of pregnancy
479
Duration of malarial chemoprophylaxis for travelers.
Antimalarial drugs 2 days to 2 weeks before departure, continued for 4 weeks after leaving an endemic area
Exceptions: Atovaquone-proguanil or primaquine – discontinued 1 week after departure from endemic area
480
Have a “dewdrop” appearance and develop in crops randomly about the trunk, extremities, and face over 3–4 days
Varicella
481
Occurs in a single dermatome and appearance of vesicles is preceded by pain for several days
Herpes zoster
482
HSV found on or around the lips
HSV-1
483
HSV found on the genitals
HSV-2
484
Herpes infection in head and neck of young wrestlers
Herpes gladiatorum
485
Herpes infection in the digits of health care workers
Herpetic whitlow
486
Hands-foot-mouth disease is caused by
Coxsackievirus A16
487
A painful, vesicular, localized S. aureus or group A streptococcal infection of the pulps of the distal digits of the hands.
Blistering dactylitis
488
Infection caused by a toxin (exfoliatin) from phage group II S. aureus
Staphylococcal scalded-skin syndrome (SSSS)
489
Impetigo contagiosa is caused by
S. pyogenes
490
Bullous impetigo is caused by
S. aureus
491
most common cause of localized folliculitis
S. aureus
492
Inflammation of sweat glands that mimic infection of hair follicles, particularly in the axillae
Hidradinitis suppurativa
493
Hot-tub folliculitis is caused by
Pseudomonas aeruginosa
494
Cat-scratch disease and Bacillary angiomatosis are caysed by
Bartonella henselae
495
Raised serpiginous or linear eruptions caused by burrowing larvae of dog or cat hookworms (Ancylostoma braziliense)
Cutaneous larva migrans
496
This is transmitted mostly in persons bitten by Simulium flies in Africa that may cause blindness
Onchocerca volvulus
497
Begins as a pruritic papule then develops within days into an ulcer with surrounding vesicles and edema and then into an enlarging ulcer with a black eschar. They may also cause chronic nonhealing ulcers with an overlying dirty gray membrane.
Cutaneous anthrax
498
Painful ulcerated lesions on the genitals
Chancroid
499
Ulcerated painless lesions on the genitals
Primary syphilis
500
Cause of erysipelas
S. pyogenes
501
An abrupt onset of fiery-red swelling of the face or extremities associated with intense pain
Erysipelas
Desquamation of the involved skin occurs 5–10 days into the illness
502
Treatment of erysipelas
Penicillin
503
Most common cause of purulent cellulitis
S. aureus
504
Most common cause of nonpurulent cellulitis
S. pyogenes
More rapidly spreading, diffuse process that is frequently associated with lymphangitis and fever
505
Elevated serum IgE is seen in patients with
Job syndrome
506
Cellulitis acquired by cat bites is caused by
Pasteurella multocida
507
P. aeruginosa causes three types of soft tissue infection, which are
Ecthyma gangrenosum in neutropenic patients
Hot-tub folliculitis
Cellulitis following penetrating injury
508
Necrotizing fasciitis is caused by
group A Streptococcus or mixed aerobic–anaerobic bacteria
509
Necrotizing fasciitis associated with gas gangrene is caused by
Clostridium perfringens
510
Necrotizing fasciitis may also be caused by strains of MRSA that produce this toxin
Panton-Valentine leukocidin (PVL) toxin
511
Massive swelling of the scrotum and penis with extension into the perineum or the abdominal wall and the legs
Fournier’s gangrene
512
Most common cause of pyomyositis
S. aureus
513
Gas gangrene of the uterus is caused by
Clostridium sordellii
Uniformly fatal and death ensues rapidly
514
Primary treatment of animal bite (prophylaxis or early infection)
Amoxicillin–clavulanate (875/125 mg PO bid)
Alternative: Doxycycline (100 mg PO bid)
515
Primary treatment of animal bite with established infection
Ampicillin–sulbactam (1.5–3 g IV q6h)
Alternative: Clindamycin (600–900 mg IV q8h) plus Ciprofloxacin (400 mg IV q12h) or cefoxitin (2 g IV q6h)
516
Primary treatment of herpex simplex infection
Acyclovir (400 mg PO tid for 10 days)
Alternative: Famciclovir (250 mg PO tid for 5–10 days) or valacyclovir (1000 mg PO bid for 10 days)
517
Primary treatment of herpex zoster infection
Acyclovir (800 mg PO 5 times daily for 7–10 days)
Alternative: Famciclovir (500 mg PO tid for 7–10 days) or valacyclovir (1000 mg PO tid for 7 days)
518
Primary treatment of Cellulitis (staphylococcal or streptococcalb,c)
Nafcillin or oxacillin (2 g IV q4–6h)
Alternative: Cefazolin (1–2 g q8h) or ampicillin/sulbactam (1.5–3 g IV q6h) or erythromycin (0.5–1 g IV q6h) or clindamycin (600–900 mg IV q8h)
519
Primary treatment of MRSA skin infection
Vancomycin (1 g IV q12h)
Alternative: Linezolid (600 mg IV q12h)
520
Primary treatment of Necrotizing fasciitis (group A streptococcal)
Clindamycin (600–900 mg IV q6–8h) plus penicillin G (4 million units IV q4h)
Alternative: Clindamycin (600–900 mg IV q6–8h) plus a cephalosporin (first- or second-generation)
521
Primary treatment of Necrotizing fasciitis (mixed aerobes and anaerobes)
Ampicillin (2 g IV q4h) plus clindamycin (600–900 mg IV q6–8h) plus ciprofloxacin (400 mg IV q6–8h)
Alternative: Vancomycin (1 g IV q6h) plus metronidazole (500 mg IV q6h) plus ciprofloxacin (400 mg IV q6–8h)
522
Primary treatment for gas gangrene
Clindamycin (600–900 mg IV q6–8h) plus penicillin G (4 million units IV q4–6h)
Alternative: Clindamycin (600–900 mg IV q6–8h) plus cefoxitin (2 g IV q6h)
523
Infections are associated with relative bradycardia. Patients have a lower heart rate than might be expected for a given body temperature. What do you call this sign?
Faget’s sign
524
For every 1°C (1.8°F) increase in core temperature, the heart rate typically rises by
15–20 beats/min
525
Indirect measures of acute-phase response
Erythrocyte sedimentation rate (ESR)
Changes relatively slowly, and its measurement more often than weekly usually is not useful
526
Direct measures of acute-phase response
C-reactive protein (CRP)
Change rapidly, and daily measurements can be useful
527
Specific situations that might prompt an infectious disease consult include (4)
Difficult-to-diagnose patients with presumed infections
Patients who are not responding to treatment as expected
Patients with a complicated medical history (e.g., organ transplant recipients, patients immunosuppressed due to autoimmune or inflammatory conditions)
Patients with “exotic” diseases
528
Prolonged febrile illnesses without an established etiology despite intensive evaluation and diagnostic testing
FUO
529
Old definition of FUO: An illness of _____ duration with fever of _______ on ____ occasions and an uncertain diagnosis despite ____ of inpatient evaluation
>3 weeks
≥38.3°C (≥101°F)
Two
1 week
530
New definition of FUO
Fever ≥38.3°C (≥101°F) on at least two occasions
Illness duration of ≥3 weeks
No known immunocompromised state
Diagnosis that remains uncertain after a thorough history-taking, physical examination, and obligatory investigations
531
Most common infectious cause of FUO
TB
532
Most common solid tumor that causes fever (6)
```
Breast
Colon
Hepatocellular
Lung
Pancreatic
Renal cell carcinoma
```
533
T or F. FUO is far more often caused by an atypical presentation of a rather common disease than by a very rare disease
True
534
A sterile thrombotic disease that occurs as a paraneoplastic phenomenon, especially with adenocarcinomas
Marantic endocarditis
535
Uncommon disorder but can often be diagnosed easily in a patient with FUO who presents with urticaria, bone pain, and monoclonal gammopathy
Schnitzler syndrome
536
Most common diagnosis of FUO among the neoplasms
Malignant lymphoma
537
T or F. All drugs can cause fever, even that commencing after long-term use
True
538
Fever artificially induced by the patient
Factitious fever
For example, by IV injection of contaminated water
More common among young women in health care professions
539
The most common infectious disease associated with FUO in elderly patients
Tuberculosis
540
Most common diseases with an atypical manifestation of FUO in elderly (2)
giant cell arteritis and polymyalgia rheumatica
541
T or F. In conducting diagnostic tests for FUO, antibiotic and glucocorticoid treatment should still be continued as treatment of possible diseases
False. Before further diagnostic tests are initiated, antibiotic and glucocorticoid treatment, which can mask many diseases, should be stopped
542
Which is a preferred obligatory test in FUO, abdominal ultrasound or CT?
Ultrasound
543
If fever persists beyond ___ after discontinuation of suspected drug, it is unlikely that this drug is the cause of fever
72
544
Noninvasive method allowing delineation of foci in all parts of the body on the basis of functional changes in tissues
Scintigraphy
CT and MRI routinely provide information on only part of the body, while scintigraphy readily allows whole-body imaging
545
In FUO, if no diagnosis is reached despite scintigraphic and PDC-driven histologic investigations or culture, what is the next step?
Second-stage screening diagnostic tests
Screening abdominal and chest CT
Bone marrow aspiration
Temporal artery biopsy
Liver biopsy
546
In FUO, when is empiric antibiotic indicated? (2)
Hemodynamic instability or neutropenia
547
Highly effective in preventing attacks of familial Mediterranean fever but is not always effective once an attack is well under way
Colchicine
548
NSAIDs has dramatic response in FUO of what disease?
adult-onset Still’s disease
549
A key cytokine in local and systemic inflammation and the febrile response
Interleukin (IL) 1
550
A recombinant form of the naturally occurring IL-1 receptor antagonist (IL-1Ra) and blocks the activity of both IL-1α and IL-1β
Anakinra
551
Accounts for most FUO-related deaths
Malignancy
Non-Hodgkin’s lymphoma carries a disproportionately high death toll
In nonmalignant FUO, fatality rates are very low
552
Body temperature is controlled by the
Hypothalamus
553
Normal core body temperature
36.5–37.5°C
554
Mean oral temperature
36.8° ± 0.4°C
Low levels at 6 am (max is 37.2°C)
Higher levels at 4-6 pm (max is 37.7°C)
555
Rectal temperatures
generally 0.4°C (0.7°F) higher than oral
Oral: 36.8° ± 0.4°C
556
Fever that most commonly occurs in patients with central nervous system (CNS) hemorrhages
Hyperpyrexia
>41.5°C
Can develop in patients with severe infections
557
Uncontrolled increase in body temperature that exceeds the body’s ability to lose heat
Hyperthermia (heat stroke)
558
T or F. Hyperthermia responds to antipyretics
False. Does not involve pyrogenic molecules
Can be rapidly fatal and characteristically does not respond to antipyretics
559
Pyrogenic products of gram-positive organisms that are also called superantigens
Enterotoxins
560
Pyrogenic cytokines (4)
IL-1, IL-6, tumor necrosis factor (TNF), and ciliary neurotropic factor
561
the primary cell types that produce pyrogenic cytokines (2)
Myeloid and endothelial cells
562
Distinct receptors for microbial products that are located on the hypothalamic endothelium and are similar in many ways to IL-1 receptors.
Toll-like receptors
563
Fever lasting 3–10 days is followed by afebrile periods of 3–10 days and are classic for Hodgkin’s disease and other lymphomas
Pel-Ebstein pattern
564
fevers occur every 21 days and accompany the neutropenia
Cyclic neutropenia
565
Relapsing fever
Borrelia infection
566
Blocks IL-1 activity and are useful in recurrent fever of autoimmune and autoinflammatory diseases (2)
Anakinra or Canakinumab
567
T or F. Acitaminophen is more effective than aspirin in reducing fever in humans
False. Oral aspirin and acetaminophen are equally effective in reducing fever in humans
568
Aspirin increases the risk of this condition in children
Reye’s syndrome
569
Difference of sepsis, severe sepsis and septic shock
* Sepsis is a systemic inflammatory response to infection
* Severe sepsis – sepsis is complicated by acute organ dysfunction
* Septic shock – sepsis complicated by hypotension despite adequate fluid resuscitation along with perfusion abnormalities
570
a dysregulated host response to infection that leads to acute organ dysfunction
Sepsis
571
Septic shock criteria includes sepsis plus (2) (despite adequate resuscitation):
* Need for vasopressor to elevate MAP to ≥65mmHg
| * Serum lactate concentration >2.0 mmol/L
572
Most common source of sepsis
Pneumonia
573
2nd most common source of sepsis
Intraabdominal and GU infections
574
Most common gram positive isolates in sepsis (2)
S. aureus and S. pneumoniae
Gram positive > gram negative
575
Most common gram negative isolates in sepsis (3)
E. coli, Klebsiella species, and P. aeruginosa
576
Structures conserved across microbial species recognized by the receptors which will lead to upregulation of inflammatory gene transcripton and initiation of innate immunity
Pathogen-associated molecular patterns (PAMP)
Lipid A moiety of LPS – common PAMP
577
Endogenous molecules released from the injured cells also recognized by the receptors that leads to inflammation
Damaged-associated molecular patterns (DAMPs)
Examples:
• High-mobility group protein B1
• S100 proteins
• Extracellular RNA, DNA and histones
578
6-organ framework that assess primary physiologic manifestations of organ dysfunction
SOFA score
24 points
579
Hypoxemia and bilateral infiltrates of noncardiac origin that arise within 7 days of the suspected infection
ARDS
580
According to Berlin criteria, mild, moderate and severe ARDS is defined as
* Mild – PaO2/FiO2 – 201-300 mmHg
* Moderate – PaO2/FiO2 – 101-200 mmHg
* Severe – PaO2/FiO2 – ≤100 mmHg
581
Difference between hydrostatic edema and ARDS
Hydrostatic edema has elevated pulmonary capillary wedge pressure > 18 mmHg
582
```
Findings in sepsis in terms of:
HR
RR
SBP
O2 sat
WBC
```
```
HR > 90 bpm
RR > 20 cpm
SBP ≤100 mmHg
O2 sat ≤90%
WBC < 4000/μL or > 12,000/μL
```
583
Quick SOFA (qSOFA) score parameters (3)
* Systolic hypotension ≤100 mmHg
* Tachypnea ≥22 cpm
* Altered mentation
Score of ≥ 2 points – sepsis
584
Marker of tissue hypoperfusion in sepsis
Arterial lactate
Hyperlactemia and delayed lactate clearance – greater incidence of organ failure and death in sepsis
585
For every 1-h delay among patients with sepsis, a ____ increase in the odds of in-hospital death is reported
3-7%
586
Initial management bundle for sepsis (4)
* Early administration of appropriate broad-spectrum antibiotics
* Collection of blood for culture before antibiotic administration
* Measurement of serum lactate levels
* Cardiorespiratory resuscitation
587
Initial management bundle of sepsis must be completed within ___ of presentation
3 h
588
Management bundle of sepsis must be completed within
6 h
589
Management bundle for sepsis
* IV fluid bolus
* Treatment with vasopressors for persistent hypotension or shock
* Re-measurement of serum lactate levels
590
Recommended as first line fluids for sepsis resuscitation
Crystalloids
591
Primary goal of supportive treatment of sepsis
To improve delivery of oxygen to the tissues as quickly as possible
592
Most widely used fluids in critically ill patients
Colloids
593
First choice vasopressors in septic shock
Norepinephrine
594
Trial that compared norepinephrine and dopamine and showed no difference observed in 28-day mortality, but arrhythmias are significantly higher with dopamine
SOAP II trial
595
Indications of mechanical ventilatory support in sepsis (4)
* Significant hypoxemia (PaO2 < 60 mmHg or SaO2 < 90%
* Hypoventilation – rising PaCO2
* Increased work of breathing
* Inadequate or unsustainable compensation for metabolic acidosis (pH < 7.2)
596
T or F. Most meta-analyses report no change in mortality but an increase in shock reversal with glucocorticoid treatment
True
International CPG suggest against the use of IV hydrocortisone to treat septic shock. If to be used, may give a dose of 200 mg/day
597
Mortality rates for septic shock
~20%
598
Rate of hospital re-admission within 90 days in sepsis
>40%
599
In patients with septic shock requiring vasopressors, the recommended target mean arterial pressure is
65 mmHg.
600
______ should be used with the intent of reducing the norepinephrine dose.
Vasopressin
601
In the management of sepsis, red blood cell transfusion is recommended only when the hemoglobin concentration decreases to _______ in the absence of acute myocardial infarction, severe hypoxemia, or acute hemorrhage.
<7.0 g/dL
602
A protocol-based approach to blood glucose management should be used in ICU patients with sepsis, with insulin dosing initiated when two consecutive blood glucose levels are
>180 mg/dL
603
Cause of acute rheumatic fever
infection of the upper respiratory tract with group A streptococci
The potential role of skin infection and of groups C and G streptococci is currently being investigated
604
The most common cause of heart disease in children in developing countries
RHD
A major cause of mortality and morbidity in adults
605
Peak age of ARF
age 5–14 years
Initial episodes become less common in older adolescents and young adults and are rare in persons aged >30 years
606
Peak age of RHD
25-40 years
More common in females
607
Serotypes of group A strep that is associated with ARF
M-serotypes
It is now thought that any strain has the potential to cause ARF
608
Human leukocyte antigen (HLA) class II alleles associated with susceptibility to ARF
HLA-DR7 and HLA-DR4
609
Human leukocyte antigen (HLA) class II alleles associated with protection against ARF
HLA-DR5, HLA-DR6, HLA-DR51, HLA-DR52, and HLA-DQ
610
The most widely accepted theory of rheumatic fever pathogenesis
Molecular mimicry
Alternative hypothesis: initial damage is due to streptococcal invasion of epithelial surfaces, with binding of M protein to type IV collagen allowing it to become immunogenic
611
Latent period between the precipitating group A streptococcal infection and the appearance of the clinical features of ARF
~3 weeks (1–5 weeks)
Chorea and Indolent carditis – prolonged latent period of 6 months
612
Most common clinical features of ARF
1. Polyarthritis – 60-75%
2. Carditis – 50-60%
Other features:
• Chorea - <2 – 30%
• Erythema marginatum – rare; <5%
• Subcutaneous nodules – rare; <5%
613
Hallmark of rheumatic carditis
Valvular damage
614
Valve that is almost always affected in RHD
Mitral valve
Aortic valve – often affected together with mitral valve
615
The characteristic manifestation of rheumatic carditis in previously unaffected individuals
Mitral regurgitation
May be accompanied by aortic regurgitation
Stenosis – may occur over ensuing years due to recurrent episodes
616
The most common form of joint involvement in ARF
Arthritis
Objective evidence of inflammation, with hot, swollen, red, and/or tender joints
617
Characteristic of arthritis in ARF
Polyarthritis
Migratory
Large joints
Asymmetric
618
Treatment of joint disease in ARF
1. Salicylates
2. NSAIDs
Joint involvement that persists for more than 1-2 days after starting salicylates is unlikely to be due to ARF
619
Chorea of ARF
Sydenham’s chorea
Found mainly in females
620
Characteristic of chorea in ARF
darting movements of the tongue
Affect particularly the head and upper limbs
Associated emotional lability or obsessive-compulsive traits
Usually resolve within 6 weeks but sometimes may take up to 6 months
621
Essential in making the diagnosis of ARF
Evidence of a preceding group A streptococcal infection
622
Most common serologic tests for ARF
1. Antistreptolysin O (ASO) titer
| 2. Anti-DNAse B (ADB) titer
623
Criteria for diagnosis of ARF
Jones criteria
624
T or F. There is no treatment for ARF that has been proven to alter the likelihood of developing, or the severity of, RHD
True
625
Drug of choice for ARF
Penicillin
1. Phenoxymethyl penicillin, 500 mg (250 mg for children ≤27 kg) PO twice daily
2. Amoxicillin, 50 mg/kg (maximum, 1 g) daily, for 10 days
3. Benzathine penicillin G of 1.2 million units (600,000 units for children ≤27 kg) IM single dose
626
DOC for the treatment of arthritis, arthralgia, and fever, once the diagnosis of ARF is confirmed
Aspirin 50–60 mg/kg per day, up to a maximum of 80–100 mg/kg per day (4–8 g/d in adults) in 4–5 divided doses
Fever, joint manifestations, and elevated acute- phase reactants sometimes recur up to 3 weeks after the medication is discontinued. This Does not indicate a recurrence and can be managed by recommencing salicylates for a brief period
Alternative drug: Naproxen
627
Glucocorticoid is used by some clinicians in ARF as treatment of
Carditis
Prednisone or prednisolone 1–2 mg/kg per day (maximum, 80 mg), usually for a few days or up to a maximum of 3 weeks
628
T or F. Long term bed rest is a cornerstone in the management of ARF
False. No longer widely practiced.
Should be prescribed as needed while arthritis and arthralgia are present and for patients with heart failure. Gradual mobilization can commence as tolerated once symptoms resolve
629
Management of chorea in ARF
1. Provide a calm environment – in milder cases
2. Carbamazepine or sodium valproate – in severe cases
3. Corticosteroids – in severe or refractory cases
4. IVIg – in small studies
Medications to control the abnormal movements do not alter the duration or outcome of chorea
630
Untreated, ARF lasts on average of
12 weeks
631
In ARF, Echocardiogram should be performed after _____ to determine if there has been progression of carditis
1 month
632
The mainstay of controlling ARF and RHD
Secondary prevention
633
Secondary prevention in ARF and RHD
Long-term penicillin prophylaxis
Patients with ARF are at dramatically higher risk than the general population of developing a further episode of ARF after a group A streptococcal infection
634
The best secondary prophylaxis for ARF or RHD
Benzathine penicillin G 1.2 million units, or 600,000 units if ≤27 kg delivered every 4 weeks. Can be given every 3 weeks, or even every 2 weeks, to persons considered to be at particularly high risk
Other drugs – less effective
Oral penicillin V 250 mg twice daily
Erythromycin 250 mg BID
635
According to the World Heart Federation Criteria for Echocardiographic Diagnosis of Rheumatic Heart Disease (RHD) in Individuals <20Years of Age, definite RHD is defined as (4)
(A) Pathologic MR and at least two morphologic features of RHD of the mitral valve
(B) MS mean gradient ≥4 mmHg (note: congenital MV anomalies must be excluded)
(C) Pathologic AR and at least two morphologic features of RHD of the AV (note: bicuspid AV and dilated aortic root must be excluded)
(D) Borderline disease of both the MV and AV
636
According to the World Heart Federation Criteria for Echocardiographic Diagnosis of Rheumatic Heart Disease (RHD) in Individuals <20Years of Age, borderline RHD is defined as (4)
1. At least two morphologic features of RHD of the MV without pathologic MR or MS
2. Pathologic MR
3. Pathologic AR
637
Diagnosis of ARF based on Jones criteria is when the criteria fulfilled are
1. 2 major
2. 1 major + 2 minor
3. 3 minor
638
Jones major criteria (5)
1. Carditis
2. Arthritis
3. Chorea
4. Erythema marginatum
5. SC nodules
639
American Heart Association Recommendations for Duration of Secondary Prophylaxis for patients with Rheumatic fever without carditis
For 5 years after the last attack or 21 years of age (whichever is longer)
640
American Heart Association Recommendations for Duration of Secondary Prophylaxis for patients with Rheumatic fever with carditis but no residual valvular disease
For 10 years after the last attack, or 21 years of age (whichever is longer)
641
American Heart Association Recommendations for Duration of Secondary Prophylaxis for patients with rheumatic fever with persistent valvular disease, evident clinically or on echocardiography
For 10 years after the last attack, or 40 years of age (whichever is longer); sometimes lifelong prophylaxis
642
A flat lesion that is due to bleeding into the skin that is <3 mm in diameter
Petechiae
643
A flat lesion that is due to bleeding into the skin that is >3 mm in diameter
Ecchymoses
644
A necrotic lesion covered with a black crust
Eschar
645
Discrete lesions that become confluent as rash spreads from hairline downward, usually sparing palms and soles; lasts ≥3 days
Rubeola (measles)
Nonspecific because they also develop in infectious mononucleosis, scarlet fever, and Zika virus infection
646
Palatal petechiase seen in Rubella
Forschheimer spots
647
Bright-red “slapped-cheeks” appearance followed by lacy reticular rash that waxes and wanes over 3 weeks; rarely, papular-purpuric “gloves-and- socks” syndrome on hands and feet
Erythema infectiosum (fifth disease)
648
Also known as 6th disease
Roseola
| Exanthem subitum
649
Exanthem subitum is caused by
Human herpesvirus 6
650
Maculopapular eruption appearing in axillae, spreading to trunk and later to extremities; usually spares face, palms, soles; evolves from blanchable macules to confluent eruption with petechiae
Epidemic typhus
651
Cause of Epidemic typhus
Rickettsia prowazekii
652
Cause of endemic typhus
Rickettsia typhi
653
Headache; musculoskeletal pain (“breakbone fever”); leukopenia; occasionally biphasic (“saddleback”) fever are symptoms of
Dengue
654
Cause of erythema marginatum
Group A streptococcus
655
Transient 2- to 5-mm erythematous papules appearing at height of fever on trunk, proximal extremities; lesions evanescent.. Other clinical manifestations are High spiking fever, polyarthritis, splenomegaly; erythrocyte sedimentation rate, >100 mm/h
Still’s disease
656
Eastern African trypanosomiasis is caused by
T. brucei rhodesiense
657
Western African trypanosomiasis is caused by
T. brucei gambiense
658
African trypanosomiasis is transmitted by what vector
Tsetse fly
659
Winterbottom’s sign is seen in
Western African trypanosoiasis
660
Posterior cervical lymphadenopathy in Western African trypanosoiasis
Winterbottom’s sign
661
Erythema multiforme is caused by (3)
1. Herpes simplex virus
2. Mycoplasma pneumoniae
3. Drug intake
662
Rat-bite fever
Haverhill fever
663
Rat-bite fever is caused by
Streptobacillus moniliformis
664
Scarlet fever is caused by
Group A streptococcus
665
Diffuse blanchable erythemabeginning on face and spreading to trunk and extremities; circumoral pallor; “sandpaper” texture to skin; accentuation of linear erythema in skin folds (Pastia’s lines); enanthem of white evolving
into red “strawberry” tongue; desquamation in second week
Scarlet fever (second disease)
666
Rash similar to scarlet fever (scarlatiniform) or EM; fissuring of lips, strawberry tongue; conjunctivitis; edema of hands, feet; desquamation later in disease
Kawasaki disease
667
Streptococcal toxic shock syndrome is caused by
Group A streptococcus
668
Macules (2–3 mm) evolving into papules, then vesicles (sometimes umbilicated), on an erythematous base (“dewdrops on a rose petal”); pustules then forming and crusting; lesions appearing in crops; may involve scalp, mouth; intensely pruritic
Varicella
669
Difference of variola (smallpox) from varicella (2)
1. Skin lesions in any given area are at same stage of development
2. Prominent distribution of lesions on face and extremities (including palms, soles)
670
Indurated plaque evolving into hemorrhagic bulla or pustule that sloughs, resulting in eschar formation; erythematous halo; most common in axillary, groin, perianal regions
Ecthyma gangrenosum
671
Large, violaceous, nonulcerative subcutaneous nodules that are exquisitely tender; usually on lower legs but also on upper extremities
Erythema nodosum (septal panniculitis)
672
Tender red or blue edematous nodules giving impression of vesiculation; usually on face, neck, upper extremities; when on lower extremities, may mimic erythema nodosum
Sweet syndrome (acute febrile neutrophilic dermatosis)
673
Palpable purpuric lesions appearing in crops on legs or other dependent areas; may become vesicular or ulcerative
Cutaneous small-vessel vasculitis
674
1- to 2-mm white or bluish lesions with an erythematous halo on the buccal mucosa
Koplik’s spots
675
Pathognomonic for measles
Koplik’s spots
Generally seen during the first 2 days of symptoms
676
Postauricular and suboccipital adenopathy and arthritis are usually seen in
Rubella
677
Cause of erythema infectiosum (fifth disease)
human parvovirus B19
678
Consists of 2- to 3-mm rose-pink macules and papules that coalesce only rarely, occur initially on the trunk and sometimes on the extremities (sparing the face), and fade within 2 days
Exanthem subitum (roseola)
679
Rash of Lyme disease
Erythema migrans
680
Rash of acute rheumatic fever
Erythema marginatum
681
Target lesions (central erythema surrounded by area of clearing and another rim of erythema) up to 2 cm; symmetric on knees, elbows, palms, soles; spreads centripetally; papular, sometimes vesicular; when extensive and involving mucous membranes, termed EM major
Erythema multiforme
682
Accentuated petechiae in body folds seen in scarlet fever
Pastia’s lines
683
In the exfoliative stage of this disease, the skin can be induced to form bullae with light lateral pressure (Nikolsky’s sign)
Staphylococcal scalded-skin syndrome
684
The skin can be induced to form bullae with light lateral pressure. This is called
Nikolsky’s sign
685
Disseminated candidiasis is often due to
Candida tropicalis
686
In immunocompromised hosts, nodular lesions often represent
disseminated infection
687
Triad of disseminated candidiasis
1. Fever
2. Myalgias
3. Eruptive nodules
688
Distinctive, sparse, countable hemorrhagic pustules, usually located near joints
Disseminated gonococcemia
