MedEd Micro 2 Flashcards
1
Q
causes of immunocompromise
A
immunodeficiency syndromes
acquired - HIV, iatrogenic, lymphopaenia, malnutrition, DM
organ specific - structural lung disease (COPD, CF), splenectomy
2
Q
what organisms are people with no spleen at risk of
A
encapsulated bacteria
ie NHS
neisseria
hamophilus
strep
3
Q
consequences of immunocompromise
A
unusual organism infections
unusual site infections
4
Q
HIV specific infections
A
PCP
JC virus
toxoplasmosis
microsporidium
MAC
(TB & CMV more severe)
5
Q
CF specific infections
A
burkolderia cepacia
6
Q
anti TNFa specific infections
A
JC virus
7
Q
HIV pts can get common infections in weird places - 2 examples of the bug with location
A
CMV colitis
oesophageal candidiasis
8
Q
what weird site infection do sickle cell pts get and from what bug
A
salmonella septic arthritis
9
Q
prophylaxis for HIV / splenectomy pts
A
vaccination (splenectomy)
ABx - co-trimoxazole (HIV)
10
Q
what feature of influenza allows antigenic shift
A
multi segmented genome
11
Q
types of influenza
A
A and B
technically 4 types but C and D aren’t that clinically relevant
12
Q
which type of influenza is worse
A
A
(its the pandemic one)
13
Q
what 3 features of influenza allow it to have pandemic risk
A
novel antigenicity
efficient replication in airways
efficient transmission between people
14
Q
2 processes that allow novel antigenicity
A
antigenic shift
antigenic drift
15
Q
what is antigenic drift
A
accumulation of errors over time
16
Q
what is antigenic shift
A
organism infected with 2 strains of influenza at the same time –> RNA from both strains mix in the same cell –> genome of virus changes
17
Q
problem with antigenic drift
A
pre formed ABs from previous infection are no longer effective against current strain
18
Q
how many chunks of RNA does influenza have
A
8
19
Q
how common is antigenic shift vs drift
A
drift is common, shift is very rare - esp to cause a functional virus as often the mix produces nonsense virus
20
Q
2 most important genes in influenza
A
neuraminidase
haemagglutinin
21
Q
what does neuraminidase do
A
cleaves sialic acid, facilitating viral release from cells
22
Q
what does haemagglutinin do
A
binds to sialic acid, facilitating viral entry
23
Q
key pandemic feature of haemagglutinin
A
prone to antigenic drift
24
Q
key pandemic feature of neuraminidase
A
prone to antigenic shift
25
how do you determine strain of influenza
RT - PCR
26
where are haemagglutinin and neuraminidase found
cell SURFACE
27
influenza antivirals
PO oseltamivir (tamiflu) ** key one
inhaled zanamivir
IV peramivir
oral baloxavir
oral amantadine
28
how does oseltamivir work
neuraminidase inhibitor
29
how does baloxavir work & when is it used
endonuclease inhibitor
only in first 2 days of infection
30
how does amantadine work
m2 antagonist
31
problem with amantadine
easy to become resistant to it - most influenza strains are resistant to it, so not used anymore
32
what herpes presentation indicates uncontrolled HIV infection
herpes oesophagitis
33
JC virus causes what presentation
progressive multifocal leucoencephalopathy (PMLE)
34
what is this persons Hep B status
HBsAg +
HBsAB -
HBcAB IgM +
HBeAg +
HBeAB -
acute hep B infection
35
what does val infront of an antiviral indicate & clinical indication
increases bioavailability + less effected by first pass metabolism
easier to take orally
36
tx ladder of human herpes viruses
aciclovir or ganciclovir
foscarnet
cidofovir
37
usual first line Tx for non herpes viruses
cidofovir 1st line
38
why do we not just treat everyone with cidofovir if its 3rd line HHV and 1st line non HHV
dirty drug - nephrotoxic, ocular toxicity, BM suppression
39
what are herpes simplex in terms of HHV
HHV 1 & 2
40
brain manifestations of HSV1 vs HSV2
1 = HSV encephalitis
2 = HSV meningitis
41
PCs of HSV1
herpes labialis (oral ulcers)
HSV encephalitis
42
PCs of HSV2
genital herpes ulcers
HSV meningitis
43
rarer presentations of HSV
HSV oesophagitis / colitis - HIV!!!!
eczema herpeticum
herpetic whitlow
disseminated cutaneous herpes - imm comp
44
what is herpetic whitlow
herpes on the finger
45
who gets herpetic whitlow
healthcare workers !!
46
1st line tx of HSV
aciclovir
47
what can initial enoculation with HSV look like (more commonly than in reactivation)
herpes gingivostomatitis - ulcers around mouth
48
what HHV is VZV
HHV3
49
PC of VZV
chicken pox and shingles
50
who gets more serious chickenpox infections
adults - esp imm supp / foetus
51
aka shingles
herpes zoster
52
2 key risks of shingles
opthalmic herpes zoster
ramsay hunt syndrome
53
what is ophthalmic herpes zoster
shingles of v1 --> damage of retina
54
sign of opthalmic herpes zoster and what this actually is
hutchinson sign
vesicles on the nose tip
55
what is ramsay hunt syndrome
facial nerve shingles
can get bells palsy, ear pain + vesicles in ear
56
what is not part of the VZV tx esp in children & why
ibuprofen
- increases secondary skin infections esp nec fasc
57
complication post shingles
post herpeticum neuralgia
- pain in distribution of dermatome
58
what is HHV4
EBV
59
PC of EBV
infectious mononucleosis
- fever, pharyngitis, lymphadenopathy
- hepatosplenomegaly
60
how can the lymphadenopathy picture differentiate EBV from tonsilitis
EBV affects posterior cervical chain
tonsilitis affects anterior cervical chain
61
what else can cause infectious mononucelosis
CMV
toxoplasmosis
62
what else can cause a similar picture to infectious mononucleosis
HIV seroconversion !
63
what lab findings strengthen a Dx of EBV
monospot test
atypical lymphocytes on smear
64
how is EBV usually diagnosed now
EBV serology
65
tx of EBV
usually supportive
gancyclovir if really bad
66
2 pieces of advice for patient with mono
avoid contact sports - splenic rupture risk
avoid alcohol - can give hepatitis
67
3 associated diseases after EBV
burkitts lymphoma
post transplant lymphoproliferative disorder
nasopharyngeal carcinoma
68
what is HHV5
CMV
69
2 potential PCs of CMV
asymptomatic or mononucelosis picture
70
buzzword of CMV
owl's eye inclusion bodies
71
4 PCs reactivation of CMV in imm supp
pneumonitis
retinitis
colitis
encephalitis
72
tx of CMV
gancyclovir / valgancyclovir
73
CT of CMV pneumonitis
ground glass widespread appearance
74
what does CMV retinitis look like
widespread cotton wool spots
75
what does CMV colitis look like
like HSV oesophagitis - hard to differentiate
owls eye inclusion body !
76
name 3 other HHV and what they cause
HHV6 & 7 - roseola
HHV8 - karposi's sarcoma
77
complication of roseola
encephalitis (rare) --> causes lots of febrile seizures
78
association of HHV8
castleman disease
primary effusion lymphoma
79
what is primary effusion lymphoma
very poor prognosis diffuse large B cell lymphoma
80
what is castlemann's lymphoma
lymphoproliferative disorder
81
what is karposi's sarcoma
lymphatic endothelium proliferation
82
what is the problem with karposi's sarcoma
lesions on the skin are fine ish
but often associated with lesions internally which can haemorrhage massively
83
what do adenoviruses cause in imm comp
pneumonitis
haemorrhagic cystitis
meningioencephalitis
colitis
84
what does JC virus cause in helathy vs imm comp ppl
healthy = nothing
imm comp = PML
85
who is most susceptible to JC virus
monoclonal ABs pts
HIV
86
Tx of JC virus
no antivirals really
treat imm supp
87
what does BK virus cause & who do we worry about it in
transplant pts !!
nephropathy - kidney transplant pts
haemorrhagic cystitis - BM transplant pts
88
which hepatitis viruses cause acute infection
A and E
89
common things between hep A and E
both cause acute infection
both faecal-oral
both seen in travellers
similar clinical presentations
can be STIs esp in MSM !!
rarely cause chronic infection, just acute
90
progression of PC of hep A/E
- inc incubation period and resolution period
incubation period 2-6 weeks
prodromal malaise
jaundice, hepatitis, cholestasis
resolution ~ 2 months
91
what complication is rare in hep A and E
fulminant hepatitis (can happen but v v v rare)
92
who would get fulminant hepatitis in hep A / E
A = elderly
E = pregnant women *** buzzword
93
tx of hep A / E
none - symptomatic
94
which hep has a vaccine
hep A and B
95
how is hep B transmitted
contaminated blood / fluids
vertically
96
how does hep B present & for how long
acutely with hepatitis
can last up to 6 months
97
is hep B fulminant
rarely
98
what % of people fail to clear hep B and what happens then
5-10%
- become chronically infected
99
what can uncontrolled hep b cause
cirrhosis
HCC
100
what is the RF of hep B becoming chronic
younger age !!
101
what does hep B sAg + indicate
have the virus present
102
what does hep B sAB + indicate
you are immune (have neutralising ABs)
103
what does hep B cAB + indicate
you have / had hep B
104
which hep B cAB is present in acute vs chronic response
IgM = acute
IgG = chronic
105
do hep B cAB confer immunity
NO - just shows you have seen the virus. its HBsAB that shows immunity
106
what is the hep B eAg a marker of
infectivity (present = highly infectious)
107
what does hep B eAB indicate
not very infectious
108
pt with only hep B cAB + only
either JUST cleared the infection
infected AGES ago
109
hep b tx
tenofovir 1st line
entecavir can be used
looooads of others that aren't as relevant for path
110
follow up of hep b
6 monthly screening for HCC - USS / AFP
111
how can hep B be prevented
vaccination !!
112
when do you get hep D
only if you have hep B too
113
3 manifestations of hep D with PC
coinfection at the same time with hep B --> ++++ severe acute hep B
superinfection (flare of hep B then get hep D) --> exacerbation of chronic hep B
aggressive, difficult to treat chronic hep B
114
Ix for hep D
anti HDV ABs
115
prognosis and tx of hep D
very very bad - get cirrhosis quickly
IFNa but not that good
116
how is hep C transmitted
bodily fluids
vertically
117
what is hep C the opposite of and why
hep B
- rarely get acute hepatitis, sometimes coryza
- very common to get chronic 60-80%
118
how does chronic hep C present
cirrhosis (dont get initial hepatitis so dont know you have it)
119
unusual presentations of hep c
glomerulonephritis
cryoglobulinaemia
vasculitis
120
Ix of HCV
viral load
serology less useful
121
hep c tx
direct acting antivirals (target parts of hep c genome)
122
how is tx for hep c judged and what is this
sustained virologic response (SVR)
- at 12 weeks, do you have a detectable viral load
123
is there a vaccine for hep c
no
124
define pyrexia of unknown origin
>38.3 degrees
+
>3 weeks
+
no known cause
+
one week of Ix
125
3 specific situations of PUO
nosocomial
neutropaenic
HIV assoicated
126
3 specific situations of PUO
nosocomial
neutropaenic
HIV associated
127
what can cause a fever
infection - classical or weird ones / weird foci
cancer - haem ones esp
AID
rare familial diseases - eg FMF, immunodefs
128
weird foci infections
IE
psoas abscess
epidural abscess
129
which AIDs can cause fever
rheumatology ones
vasculitis
still's disease **buzzword
130
buzzwords of typhoid fever PC
rose spots
nosebleeds
constipation
fagets sign
131
what ABx is usually used to treat weird infections
doxycycline
132
cause of typhoid
salmonella typhi or paratyphi
NOT the other salmonella
133
who gets typhoid and how
travellers from India
foecal - oral
134
what is fagets sign
relative bradycardia (usually HR increases if fever)
135
incubation of typhoid
1-2 weeks
136
gold standard Ix for typhoid
BM culture
137
actual tests for typhoid
cultures
serology (widal test)
138
tx of typhoid
ceftriaxone
139
where does typhoid live
peyers patch
140
complication of typhoid
haemorrhage from ruptured peyers patch
141
where is the dengue traveller coming back from
SE asia - thailand / cambodia
142
transmission of dengue
mosquitoes
143
how many serovars are there of dengue
4
144
2 buzzwords of dengue
retro-orbital headache
suburn rash
145
incubation of dengue
2 weeks
146
tx of dengue
supportive tx as they will get better on their own usually
147
2 serious ways dengue can present
dengue shock syndrome
dengue haemorrhagic fever
148
why do people get the more serious dengue presentations
previously infected with dengue (more common in people who live in these countries)
149
cause of malaria
plasmodium spp
150
where do you travel to to get malaria
africa / south asia / se asia / central or south america
151
how does malaria present
paroxysms (episodes) of fever and rigors
anaemia, jaundice, hepatosplenomegaly, haemaglobinuria
152
incubation of malaria
depends on species infected with
153
fatal complications of malaria
shock
ARDS
cerebral malaria
blackwater fever
DIC
154
what is blackwater fever & classical sign of it
pronounced haemolysis --> kidney damage
get BLACK urine
155
how is malaria Dx
thick and thin blood film
156
name the species of malaria
plasmodium:
falciparum
vivax
ovale
knowlesi
malariae
157
which species of malaria causes the fatal disease
fallciparum
158
which species of malaria requires treatment of hypnozoites (bcos they are the only ones to produce hypnozoites)
vivax and ovale
159
which species of malaria have tertian pattern with 48hr paroxysms
falciparum, ovale, vivax
160
which species of malaria have quotidian patterns and how long are the paroxysms
knowlesi - 24hrs
malariae - 72hrs
161
what is schizont and where do they form
big ball of developing malaria
- in liver / RBC
162
describe malaria lifecycle
mosquito bites you
releases sporozoites
travels to liver and forms schizont
schizont ruptures - releasing immature parasites to blood stream
each invades a RBC
forms schizont in RBC which ruptures and releases again
continues cycle
163
which bit of the cycle is responsible for periods of fever
schizont in RBC rupturing
164
which malarias can present 6-7 years after exposure in acute phase and why
ovale and vivax
- make hypnozoites which can lay dormant in liver then randomly make schizont later
165
tx of severe malaria
IV artesunate
166
indications for IV artesunate in malaria
severe
parasitaemia >2%
hypoglycaemia
metabolic / lactic acidosis
severe anaemia (70/80ish)
167
tx of less severe malaria
artemesin combo tx or chloroquine
168
what other tx does vivax / ovale need
primaquine
169
buzzwords of brucellosis RFs
raw dairy / unpasteurised milk
cattle / farms
170
buzzwords of brucellosis PC
lower back pain (epidural abscess)
epididymo-orchitis
171
dx of brucellosis
cultures
172
tx of brucellosis
doxycycline
173
buzzwords of rabies RFs
dogs / bats bites
174
what causes rabies
lyssavirus
175
buzzwords of rabies PC
hydrophobia
excessive salivation
furious / dumb encephalitis (angry or sedated)
176
incubation of rabies
1-3 months
177
tx of rabies & time frame
rabies Ig / vaccine
only BEFORE they are sx - otherwise dead
178
what CSF PCR result is pathognomonic for rabies
negri bodies
** buzzword
179
potential dx of rabies
biopsy from nape of neck
usually just clinically tho as its so rapidly progressing
180
buzzwords for RFs for plague
rats esp fleas on rats
181
buzzwords for PC of bubonic plague
buboes - massive lymph nodes which when aspirated show a dense BLACK fluid
182
cause of plague
yersinia pestis
183
tx of plague
doxycycline
184
how can bubonic / septicaemic plague also present
peripheral gangrene
185
buzzwords for RFs for leptospirosis
rat urine - outdoor water activities
186
buzzwords for PC of leptospirosis
jaundice
conjunctival suffusion (dry, no exudate)
187
incubation of leptospirosis
1 week
188
tx of leptospirosis
doxycycline
ceftriaxone if severe
189
buzzwords for bartonellosis RFs
kittens
"cat scratch fever"
190
buzzwords for bartonellosis PC
lymphadenopathy proximal to scratch
papule where scratch
parinaud oculoglandular syndrome
191
what is parinaud oculoglandular syndrome
conjunctivitis
big lymph nodes infront of ear
192
tx of bartonellosis
doxycycline
193
buzzwords of lyme disease RFs
ticks (ixodes tick) - usually been outdoors in woods etc
194
buzzwords of lyme disease PC
bullseye rash (erythma migrans)
--> Dx of lyme if present
195
complications of lyme disease
arthralgia
heart blocks
196
tx of lyme disease
doxycycline
197
buzzwords of leishmaniasis RFs
sandflies
198
buzzwords of leishmaniasis PCs
visceral - hepatosplenomegaly, pancytopaenia
cutaneous - well demarcated lesion at site of bite. can be very destructive ulcers
mucocutaenous - VERY destructive of mouth / nose
199
dx of leishmaniasis
microscopy
200
tx of visceral leishamniasis
liposomal amphoterocin B
201
buzzwords of anthrax RFs
wild animals - spores in hairs
202
buzzwords of anthrax PC
eschars (boil on skin --> painless necrotic skin lesion)
widened mediastinum (pulmonary anthrax)
203
dx of anthrax
microscopy or culture
204
tx of anthrax
doxycycline
205
classical superficial fungal infections
dermatophytoses (tinea / ringworm)
pityriasis versicolor
206
cause of tinea
trycophytum rubera
207
which tinea can be treated with topical antifungals
tinea pedis (athletes foot)
tinea cruris (groin)
tinea corporis (body)
tinea manuum (hands / palms)
208
which tinea can't be cleared with topical antifungals, and require systemic antifungals
tinea capitis (scalp / hair)
tinea unguium (nails)
209
PC of pityriasis versicolor
multiple tan/brown lesions across trunk (hypopigmented in darker skin), abdo, face
210
tx of pityriasis versicolor
antifungal shampoos / topical azoles
211
PC of candida
oral thrush
vaginal thrush
disseminated
oesophageal
212
who gets the following candida:
oral
oesophageal
dissemninated
asthmatics bcos of steroid inhaler
severe imm supp
central access lines
213
2 specifc blood tests for candida & results
beta D glucan +
galactomannan -
214
tx of severe candida
amphoterocin B
echinocandins
215
3 PC of aspergillus
aspergilloma
invasive aspergillosis
ABPA
216
blood test result for aspergillus
beta D glucan +
galactomanna + (candida in comparison in negative)
217
who gets aspergilloma
pre existing cavity in lung eg abscess
218
who gets invasive aspergillosis
imm supp
219
what is ABPA
hypersensitivity reaction to colonisation
- NOT an infection
220
tx of aspergillus
amphoterocin B
(NOT ABPA - not an infection - give steroid)
if aspergilloma - surgical removal of the fungi
221
buzzword of sporotrichosis (RFs and Sx)
contracted from rose thorns - gardeners / farmers
necrotic patchy rash spreading proximally
222
buzzword for mucormycosis
DM pts following COVID
gets rhinocerebral infection (big necrosis on face)
223
what is a prion
misfolded PrPc protein (should be alpha helix --> now beta pleated sheet which can't be broken down)
224
what do prions do to the normal PrPc proteins
make the normal ones misfold to form prions
225
PC of prion disease
rapid neurodegeneration
226
most common prion diseases
creutzfeldt jakob disease
227
3 forms of CJD and prevelance
sporadic 85%
familial 5-15%
acquired <1% eg iatrogenic. inc variant !!
228
what causes variant CJD
eaten beef with mad cow disease
229
dx of CJD
clinically
biopsy PM
in variant --> can do tonsillar biopsy
230
buzzwords of kuru
papau new guinea
ritual cannibalism
231
2 familial prions
fatal familial insomnia
gerstmann-straussler-scheinker (better prog)
