Protozoal Infections Flashcards
(200 cards)
1
Q
The ________ are well
known for their adverse intra-uterine effects on the
fetus
A
TORCH organisms (TORCH being an acronym for toxoplasmosis, rubella, CMV and herpes)
2
Q
The major protozoal diseases of humans are:
- blood: _______
- GIT: _________
- tissues: ________
A
malaria, trypanosomiasis
giardiasis, amoebiasis, cryptosporidium
toxoplasmosis, leishmaniasis, babesiosis
3
Q
Four infections—EBV, primary HIV, CMV and
toxoplasmosis—produce almost identical clinical
presentations and tend to be diagnosed as ______ or ______
A
glandular
fever or pseudoglandular fever
4
Q
a febrile illness caused by the herpes (Epstein–
Barr) virus
A
Epstein–Barr mononucleosis (EBM)
5
Q
3 froms of EBM
A
the febrile,
the anginose (with sore throat)
glandular (with lymphadenopathy
6
Q
Age of onset of EBM
A
It may occur at any age but usually between 10 and
35 years; it is commonest in 15–25 years age group.
7
Q
IP for EBM
A
The incubation period is at least 1 month
but data are insufficient to define it accurately
8
Q
Transmission of EBM
A
transmitted only by close contact, such as
kissing and sharing drinking vessels.
9
Q
Progress of the primary infection is checked
partly by specific antibodies (which might prevent
cell-to-cell spread of the virus) and partly by a cellular
__________, which
eliminates the infected cells
A
immune response, involving cytotoxic T-cells
10
Q
The rash of EBM is almost always related to _____
A
antibiotics
given for tonsillitis
11
Q
rash associated wtih EBM
A
The primary rash, most
often non-specific, pinkish and maculopapular
12
Q
The rash of EBM is similar to
A
rubella)
13
Q
The secondary rash of EBM is most often precipitated
by one of the penicillins, especially____ and ____
A
ampicillin or
amoxycillin
14
Q
5 clinical manifestations of EBM
1 2 3 4 5 6
A
Exudative pharyngitis (84%)
Petechiae of palate (not pathognomonic) (11%)
Lymphadenopathy, especially posterior cervical
Rash—maculopapular
Splenomegaly (50%)
Jaundice ± hepatomegaly (5–10%)
15
Q
Lab tests associated with EBM
WCC shows _____
Blood film shows______
A
absolute lymphocytosis
atypical lymphocytes
16
Q
Lab tests associated with EBM
______ or _____ is positive (although positivity can be
delayed or absent in 10% of cases).
A
Paul–Bunnell or Monospot test for heterophil
antibody
17
Q
Lab tests associated with EBM
Diagnosis confirmed (if necessary) by
1
2
3
A
- EBVspecific antibodies,
- viral capsule antigen (VCA) antibodies—IgM, IgG and
- EB nuclear antigen (EBN-A).
18
Q
False positives for the Paul–Bunnell test are
1
2
3
A
- hepatitis
- Hodgkin lymphoma
- acute leukaemia
19
Q
EBM usually runs an uncomplicated course over ____
weeks. Major symptoms subside within ____weeks
A
6–8
2–3
20
Q
EBM
Patients should be advised to take about_____ weeks off
work.
A
4
21
Q
Common cx of EBM 1 2 3 4
A
Antibiotic-induced skin rash
Prolonged debility
Hepatitis
Depression
22
Q
Cardiac cx of EBM
1
2
A
- myocarditis
* pericarditis
23
Q
Hema Cx of EBM
1
2
3
A
- agranulocytosis
- haemolytic anaemia
- thrombocytopenia
24
Q
Respi Cx of EBM
A
upper airway obstruction (lymphoid hypertrophy
25
```
Neuro Cx of EBM
1
2
3
4
```
* cranial nerve palsies, especially facial palsy
* Guillain–Barré syndrome
* meningoencephalitis
* transverse myelitis
26
Tx of EBM
Gargle soluble _____ to soothe
the throat
aspirin or 30% glucose
27
EBM Tx
_____ reserved for: neurological
involvement, thrombocytopenia, threatened
airway obstruction. Not recommended for
uncomplicated cases
Corticosteroids
28
Other agents that cause typical EBM syndrome
1
2
3
* HIV infection (acute initial illness)
* CMV
* toxoplasmosis
29
Exudative tonsillitis resembling EBM
1
2
3
* acute streptococcal pharyngitis
* adenovirus infection
* diphtheria (unlikely in Australia
30
Virus associated with CMV
The
| virus (human herpes virus 5)
31
Most at risk of CMV
1
2
3
1AIDS, and also in recipients of solid
| organ transplants and bone marrow grafts
32
______of AIDS patients are infected with CMV and
90%
33
The
incubation period of CMV ranges from ____ days
and the illness generally lasts about ______weeks
20 to 60
2 to 6
34
CMV perinatal dse Cx
Intrauterine infection may cause serious
abnormalities in the fetus, including:
```
1
2
3
4
5
```
```
CNS involvement (microcephaly, hearing defects, motor
disturbances),
jaundice,
hepatosplenomegaly,
haemolytic anaemia and
thrombocytopenia
```
35
Acquired CMV infection
In healthy adults, CMV produces an illness similar
to_____
However, ____ and ______ are rare
EBM
cervical lymphadenopathy and exudative
pharyngitis
36
Fever pattern of CMV
The fever often manifests as quotidian
intermittent fever spiking to a maximum in
the mid-afternoon and falling to normal each
day
37
Acquired CMV Infection:
There is often a relative
lymphocytosis with atypical lymphocytes but
the ______ test is negative
heterophil antibody
38
Acquired CMV Infection diagnosis
Specific diagnosis can be made by
demonstrating rising antibody titres from acute
and convalescent (2 weeks) sera.
What indicates recent infection?
A four-fold
| increase indicates recent infection.
39
Acquired CMV Infection diagnosis
Where can the virus be isolated?
The virus can be isolated from the
| urine and blood.
40
```
Disseminated CMV infection occurs in the
immune-deficient person, notably HIV infection
causing
1
2
3
```
opportunistic severe pneumonia,
retinitis (a feature of AIDS), encephalitis and
diffuse involvement of the gastrointestinal tract
41
T or F, CMV infection in immunocompetent needs to be treated with antivirals?
F
42
CMV Infection
In immunosuppressed
patients various antiviral drugs, such as
____, _______, ______
have been used with some benefit. 4
ganciclovir, foscarnet and fomivirsen(intraocular)
43
Toxoplasmosis
The definitive host in its life
cycle is the______ and the ______is an
intermediate host
cat (or pig or sheep)
human
44
Toxoplasmosis infection via?
through eating foodstuffs contaminated by
| infected cat faeces
45
```
The five major clinical forms of toxoplasmosis
1
2
3
4
5
```
1. asymptomatic lymphadenopathy
2. lymphadenopathy with a febrile illness
3. acute primary infection
4. neurological abnormalities
5. congenital toxoplasmosis
46
MC clinical form of Toxoplasmosis
asymptomatic lymphadenopathy
47
Toxoplasmosis similar to EBM
lymphadenopathy with a febrile illness
48
clinical form of Toxoplasmosis
febrile illness similar to acute leukaemia or EBM; a rash,
myocarditis, pneumonitis, chorioretinitis and
hepatosplenomegaly can occur
acute primary infection
49
Neuro abn asstd with Toxoplasmosis
includes headache
| and neck stiffness, sore throat and myalgia
50
this is a rare
problem but if it occurs it typically causes CNS
involvement and has a poor prognosis
congenital toxoplasmosis
51
Diagnosis of Toxoplasmosis?
Diagnosis is by serological tests (to show a four-fold
| rise in antibodies), which are sensitive and reliable
52
T or F
Toxoplasmosis in children:
Children under
5 years may be treated to avoid the possible occurrence
of chorioretinitis.
T
53
Toxoplasmosis Tx
Symptomatic patients are treated
with _________.
Clindamycin is usually used in _____
pyrimethamine plus sulphadiazine
pregnant patients.
54
Mosquito-borne infections have devastating
consequences in tropical regions
while others cause less morbidity and include ____
Ross
| River fever
55
Epidemic polyarthritis of Ross River virus, which is
| an ______, occurs in all states of Australia
alpha virus
56
Ross River fever
* All age groups, especially _____ years
* Incubation period ______
20–30
3–21 days (usually 7–11)
57
Ross River fever
MC sx
1
2
3
1. Polyarthritis (75% of patients
2. Maculopapular rash
3. Myalgia
58
Involvement of arthritis in pts with Ross River fever
mainly fingers,
| wrists, feet, ankles and knees
59
poor prognostic sign in pts with Ross River fever
tenosynovitis around the
| wrists and ankles
60
Ross River fever
In many patients the illness resolves within 2 to 6
weeks and most feel normal within 3 months, but
some with a more severe arthritis can enter a chronic
phase lasting ____
18 months or more
61
Ddx of Ross River fever
other viral infections
that cause arthritis, such as hepatitis B, rubella, Barmah
Forest virus (a mosquito-borne virus) and dengue, and
early rheumatiod arthritis and rheumatic fever.
62
Tx of Ross River fever
Treatment is symptomatic with bed rest and simple
| analgesics such as aspirin.
63
Tx of Ross River fever
Oral CS should always be used
Oral corticosteroids are effective but
| should be avoided if possible
64
```
Infections in the past 20 years which emerged and have no cure
1
2
3
4
5
```
1. infant diarrhoea,
2. Legionella pneumophila,
3. Lyme borreliosis (Lyme disease),
4. the Hantaan virus (which can cause a fatal haemorrhagic
fever) ,
5. HIV and hepatitis E and C
65
The deadly haemorrhagic fevers that have broken
out in isolated endemics include the
1
2
3
1. zoonotic African diseases—Ebola haemorrhagic fever,
2. Marburg haemorrhagic fever and
3. Lassa fever.
66
Top 5 deadly infectious diseases:
```
1
2
3
4
5
```
```
1 Acute lower respiratory infections (mostly pneumonia)
2 Diarrhoeal diseases
3 HIV/AIDS*
4 Tuberculosis
5 Malaria
```
67
the paramyxoviruses—__________which causes haemorrhagic and pulmonary
complications;
Hanta (RNA)
| virus,
68
the ______ family, which are
naturally harboured in fruit bats and include Hendra
virus, Nipah virus and Cedar virus
henipavirus
69
Another serious infection that emerged sporadically
was the so-called ‘flesh eating’ __________
infection, which was a particularly virulent strain
causing localised destruction of soft tissue
Streptococcus A
70
______ caused by a mosquito transmitted
virus and carried by birds has surfaced
in the US and beyond, causing thousands of cases and
hundreds of deaths
West Nile encephalitis
71
malaise + cough + weight loss ±
| fever / night sweats ( ± erythema nodosum
PTB
72
is the presence of infection without evidence
of active disease and inability to transmit the
infection.
Latent TB infection (LTBI)
73
reactivation rate in pts with LTBI
10%
74
LTBI
The _______is primarily intended to identify these people with a view to prophylaxis therapy.
tubercular skin test
75
Tx of LTBI
The standard preferred
regimen is isoniazid (10 mg/kg up to 300 mg (o) daily
for 6–9 months).
76
MC site of extrapulmonary TB in Australians
lymph nodes (the commonest, especially in young adults and children)
77
This disorder follows diffuse dissemination of
tubercle bacilli via the bloodstream especially in those
with chronic disease and immunosuppression
Miliary TB
78
Miliary TB
It can occur within ____ of the primary infection or much
later because of reactivation
3 years
79
CXR of miliary TB
The classic chest X-ray is multiple
| 1–2 mm nodules in lung fields
80
The lifetime risk of TB disease in children with LTBI is in the order of
5–15%.
81
Children with LTBI should be considered for
| prophylaxis with a course of _____
isoniazid
82
_____ is the more common form in
young children.______ is more common in
adolescents
Primary disease
Reactivation
83
New and promising diagnostic for PTB
immunochromatographic finger-prick test
84
Tb Dx
________—less sensitive than culture
NAAT/PCR test
85
TB Dx
_______ test should be performed
prior to BCG vaccination in all individuals over
6 months of age
A tuberculin (Mantoux)
86
Mantaux test results
<5 mm—_______
negative
87
T or F
Mantaux may be negative in
presence of very active pulmonary infection
T
88
Mantaux test results
5–10 mm
typical of past BCG vaccination
89
Mantaux test results
>5 mm
significant in immunocompromised,
| close contacts and HIV infection
90
Mantaux test results
>10 mm
positive = tuberculosis infection
| (active or inactive
91
Mantaux test results
| active or inactive
• >15 mm
highly significant for ‘normal’ people
92
The BCG vaccination should be given if the
| reaction is ______ induration
<5 mm
93
T or F
Do not give BCG for a reaction >5 mm.
T
94
BCG vaccination is recommended for:
* ATSI neonates in regions of high incidence
* neonates born to patients ______
* children <5 years ______
with leprosy or family history of leprosy
travelling for long periods to
countries of high TB prevalence
95
BCG vaccination should be considered for:
1. neonates in household with immigrants or
visitors recently arrived from countries of high
prevalence (e.g. ________)
2. children and adolescents <16 years with
continued exposure to active TB patient and
where_______
South-East Asia
isoniazid therapy is contraindicated
96
T or F
tuberculin
test not necessary for neonates <14 days
T
97
BCG vaccination is contraindicated for:
```
• tuberculin reactions ______
• immunocompromised or malignancies involving
bone marrow lymphatics
• high-risk HIV infection
• significant _____
• generalised skin diseases, _______
• pregnancy
• previous infection
```
>5 mm
fever or intercurrent illness
including keloid
tendency
98
WHO Tx strategy for patients with MDR TB
‘DOTS plus’ to control MDR-TB
99
______mg daily is recommended for adults
| taking isoniazid
Pyridoxine 25
100
A _____regimen is also an option if DOT is employed.
3-times-weekly
101
It presents either as a primary lesion or through
| the chance finding of positive syphilis serology
Syphilis
102
Congenital syphilis is rare where there is
| general serological screening of ______
antenatal patients
103
Syphilis
The primary lesion or_____ usually develops at
the point of inoculation after an incubation period
averaging 21 days.
chancre
104
Untreated, early clinical syphilis usually resolves
spontaneously within ______, leading to latent
disease, which may proceed to late destructive lesions
4 weeks
105
The most common feature of the secondary
stage of infection is a _____, which is present in about
80% of cases
rash
106
rash typical of secondary syphilis
The rash is typically a symmetrical,
generalised, coppery-red maculopapular eruption on
the face, trunk, palms and soles and is neither itchy
nor tender.
107
difference of secondary syphilis from other diseases
It can resemble any skin disease except
| those characterised by vesicles.
108
Positive serology in a patient without symptoms or
signs of disease is referred to as _____ and is
the commonest presentation of syphilis in Australia
today
latent syphilis
109
Tertiary manifestation of syphilis (follows >2 years’
latency), which is very rare, may be ‘benign’ with
development of __________ in
almost any organ, or more serious with cardiovascular
or CNS involvement
gummas (granulomatous lesions)
110
Syphilis should not be overlooked as a cause of ___ or ______
oral or
| anorectal lesions
111
T or F,
In patients with AIDS and syphilis, standard regimens
for syphilis are not always curative.
T
112
Lymphadenopathy in a patient with HIV
| infection may be due to coexisting _____
secondary syphilis
113
Spirochaetes can be demonstrated by microscopic
examination of smears from early lesions using dark
field techniques and provide an immediate diagnosis in
symptomatic syphilis. The _______ can be used on this smear.
direct fluorescent antibody techniques (FTAABS)
114
Serologic tests for syphilis
1. __________—not specific for syphilis but useful for screening
2. _________)—
specific tests, with the latter being sensitive and
widely used
3. ______—very sensitive
reagin tests (VDRL and RPR)
treponemal tests (TPPA, TPI, EIA, FTA-abs
PCR (blood or CSF)
115
_______can be a difficult problem to
diagnose but must be considered in the differential
diagnosis of fever, especially in patients with a history
of cardiac valvular disorders
Infective endocarditis
116
Course of IE
insidious course and is
| referred to as subacute (bacterial) endocarditis
117
```
Reason why there is increasing incidence of IE
1
2
3
4
```
```
1. elderly people with degenerative valve
disease,
2. more invasive procedures,
3. IV drug use and
4. increased cardiac catheterisation
```
118
Responsible organisms for IE
```
• _______ (50% of cases) most
susceptible to penicillin
• Streptococcus bovis
• Enterococcus faecalis
• _______ (causes 50% of acute form)
```
Streptococcus viridans
Staphylococcus aureus
119
Responsible organisms for IE
* _______ (IV drug users)
* Staphylococcus epidermidis
* _______ (Q fever)
* _____ (Gram –ve bacilli) (5–10% of cases)
Candida albicans/Aspergillus
Coxiella burnetii
HACEX group
120
Infective endocarditis without cardiac murmur
is frequently seen in _____ who develop
infection on the _____
IV drug users
tricuspid valve.
121
Warning signs for development
of endocarditis
* _______ of heart murmur
* _______ of a new murmur
* Unexplained _____and cardiac murmur
Change in character
Development
fever
122
In IE:
The ‘classic tetrad’ of clinical features:
7 signs of
infection, signs of heart disease, signs of embolism,
immunological phenomena
123
Dxtic tests in pts with IE
FBE and ESR
ESR ↑, anaemia and leukocytosis
124
Dxtic tests in pts with IE
urine: ____ and _____
proteinuria and microscopic haematuria
125
Dxtic tests in pts with IE
blood culture: positive in about _____ 7 (at least 3
sets of samples—aerobic and anaerobic culture)
75%
126
Dxtic tests in pts with IE
echocardiography—to visualise vegetations (______
more sensitive than TTE)
• chest X-ray
• ECG
TOE
127
IE Tx
Bactericidal antibiotics are chosen on the basis of _________
the results of the blood culture and antibiotic sensitivities.
128
How many blood cultures should be sent for IE dx
Four blood cultures should be sent to the laboratory within the first hour of admission and treatment should seldom
be delayed longer than 24 hours
129
Abx for IE
1
2
3
Benzylpenicillin, gentamicin and flucloxacillin/
| dicloxacillin are recommende
130
Abx for IE
____ is indicated in certain circumstances
Vancomycin
131
The evidence for prophylaxis of endocarditis is not
| clear, and current international practice is :
not to treat
low-risk cardiac abnormalities having procedures
with a low incidence of bacteraemia
132
Pts at low risk for IE: No need for abx
patients with murmurs not due to ____
isolated_____,
pacemakers,
implanted defibrillators,
previous _______
previous CABGS,
_____without regurgitation,
complete surgical or device closures of_________
valve disorders,
secundum ASD
rheumatic fever without valve dysfunction,
mitral valve prolapse
congenital heart defects
133
Procedures requiring prophylaxis for IE
Dental: invasive dental surgery—any procedure
causing ________
bleeding from gingiva, bone or mucosa
134
Procedures requiring prophylaxis for IE
genitourinary procedures in the presence ___
of infection
135
example of GU procedures with high infection risk
D&C, IUCD, urethral
dilatation, circumcision, prostatic surgery,
vaginal delivery in presence of infection or
prolonged labour
136
Procedures requiring prophylaxis for IE
```
respiratory tract procedures—
1
2
3
4
```
tonsillectomy/ adenoidectomy,
rigid bronchoscopy, nasal and
sinus surgery
137
Will you give IE Prophylaxis?
incision and drainage of local abscess, for
example, boils, perirectal, dacryocystitis
Yes
138
What organisms to cover for dental procedures?
Dental procedures and URT interventions ( S.viridans
| and Streptococcus cover
139
Abx Dental procedures and URT interventions
____________1 hour beforehand (if not on long-term
penicillin)
amoxycillin 2 g (50 mg/kg up to adult dose)
| orally,
140
Abx Dental procedures and URT interventions
(amoxy) ampicillin 2 g (50 mg/kg up to adult
dose) IV just before procedure commences or IM
30 minutes before if having a _____
general anaesthetic
141
Abx Dental procedures and URT interventions
if hypersensitive to penicillin: ____ or _____
clindamycin or
| vancomycin
142
Organisms to cover for GU procedures
Enterococci prophylaxis
143
Prophylaxis for GU Procedures
• amoxy/ampicillin (child: 50 mg/kg up to 2 g) IV
(just before procedure)
or
• amoxy/ampicillin 2 g (child 50 mg/kg up to 2 g)
IM, 30 minutes beforehand
144
Prophylaxis for GU Procedures
If hypersensitive to penicillin: ______
vancomycin or teicoplanin plus gentamicin.
145
_______ are those diseases and infections that are
naturally transmitted between vertebrate animals
and humans
Zoonoses
146
Think of a zoonosis in patients presenting with a __________
flu-like
| illness and features of atypical pneumonia
147
Considerations for rash
Consider rickettsial illness such as leptospirosis,
| Q fever, Lyme disease
148
Considerations for Cough or atypical pneumonia
Consider Q fever, psittacosis, bovine TB
149
Considerations for Arthralgia/arthritis
Consider Lyme disease, Ross River fever
150
Considerations for Meat workers
Consider Q fever, leptospirosis, orf, anthrax
151
Considerations for Papular/pustular lesions
Consider orf, anthrax (black)
152
Other names for Brucellosis
Brucellosis (undulant fever, Malta fever
153
IP for acute brucellosis
Incubation period 1–3 weeks
154
Classic fever pattern of acute Brucellosis
undulant
155
Cx of brucellosis
Complications such as epididymo-orchitis,
| osteomyelitis and endocarditis can occur
156
brucellosis
```
Localised infections in sites such as
1
2
3
4
5
6
are possible but uncommon
```
bones, joints, lungs, CSF, testes and cardiac valves
157
Symptoms of chronic brucellosis are virtually
indistinguishable from ______ and
can present with ____
chronic fatigue syndrome
FUO.
158
Diagnosis of brucellosus
```
• _______ if febrile (positive in 50% during
acute phase) 10, 13
• _________(rising titre)—acute
and convalescent (3–4 weeks) samples
• ______—sensitive and rapid
```
Blood cultures
Brucella agglutination test
Brucella PCR testing
159
Adult Tx of brucellosus
Adults: _______ or __________
doxycycline 100 mg (o) bd for 6 weeks +
rifampicin 600 mg (o) daily for 6 weeks
gentamicin 4–6 mg/kg/day IV statim then daily
for 2 weeks (monitor
160
Tx of brucellosus
Children:
cotrimoxazole + rifampicin
or
gentamicin
161
% relapse of brucellosus
10%
162
How to prevent brucellosus
Involves eradication of brucellosis in cattle, care
| handling infected animals and pasteurisation of milk
163
T or F
No vaccine is currently available for use in humans to prevent brucellosus
T
164
It is
the most common abattoir-associated infection in
Australia and can also occur in farmers and hunters.
Q fever
165
Agent causing Q fever
Coxiella burnetii
166
Q fever
______ is not a major feature but can occur if the
infection persists without treatment
Rash
167
Q fever
Persistent infection may cause _______ or ______ so patients with valvular disease are at
risk of endocarditis
pneumonia or
| endocarditis
168
What is the culture of Brucella IE
culture is negative
169
fever + headache + prostration
Q fever
170
Diagnosis of Brucellosis
• Serodiagnosis is by antibody levels in acute phase
and 2–3 weeks later _______ increase)
• Coxiella burnetii _____
(4-fold
PCR
171
Tx of Brucellosis
Doxycycline 100 mg (o) bd for 14 days
172
Tx of Brucellosis
For endocarditis or chronic disease
prolonged course of doxycycline plus clindamycin or
| rifampicin
173
Tx of Brucellosis
Children: >8 same antibiotics according to
weight; <8________ (instead of doxycycline
cotrimoxazole
174
The disease can be prevented in abattoir workers by
| using _____
Q fever vaccine
175
In Australia it is almost exclusively an
occupational infection of farmers (especially with
flooded farmland in tropics) and workers in the meat
industry.
Leptospirosis
176
Leptospirosis
Early diagnosis is important to prevent it passing into the ______
immune phase
177
IP for Leptospirosis
Incubation period 3–20 days (average 10)
178
Leptospirosis
Some may develop the immune phase (after an
asymptomatic period of 1–3 days) with aseptic meningitis
or jaundice and nephritis
What is this called?
icterohaemorrhagic
| fever, Weil syndrome
179
abrupt fever + headache + conjunctivitis
leptospirosis
180
Tx of Lepto
1
2
3
```
• Doxycycline 100 mg (o) bd for 5–7 days
or
• benzylpenicillin 1200 mg IV, 6 hourly for 5–7
days
or
• ceftriaxone 1 g IV daily for 5-7 days
```
181
Very infective, it is caused by a spirochaete,
Borrelia burgdorferi, and transmitted by Ixodes ticks,
so that people living and working in the bush are
susceptible.
Lyme disease
182
Pathognomonic rash of Lyme
The pathognomic sign is erythema migrans—a
characteristic pathognomonic rash, usually a
doughnut-shaped, well-defined rash about 6 cm in
diameter at the bite site.
183
Stages of Lyme
1
2
3
Stage 1: erythema migrans, flu-like illness
Stage 2: neurological problems such as limb
weakness and cardiac problems
Stage 3: arthritis
184
Tx of Lyme
Treatment
• Remove tick
• A typical regimen for adults is doxycycline
100 mg bd for 21 days or amoxycillin
185
Most patients are bird fanciers. ____ accounts
| for 1–5% of hospital admissions for pneumonia
Psittacosis
186
MR from Psittacosis
Mortality can be as high as 20% if untreated.
187
Psittacosis Dx
1
2
* Serology—rising antibody and PCR
| * Chest X-ray
188
Psittacosis Tx
• Doxycycline 200 mg (o) or clarithromycin 250 mg,
| 12 hrly for 14 days (o)
189
Listeriosis is caused by_____
Listeria monocytogenes
190
Where can Listeria monocytogenes be found?
food and has been found in many fresh and processed
| foods
191
Pts at high risk for Listeriosis
high-risk groups such as pregnant women, the
immunocompromised, frail aged, and very young
but especially neonates and fetuses
192
Tx of Listeriosis
Amoxycillin 1 g (o) 8 hourly or IV for 10–14
| days
193
A total of ______ of patients with tetanus have no
| identifiable wound of entry
10–20%
194
```
Gas gangrene (clostridial myonecrosis) is caused
by entry of one of several clostridia organisms, for
example, __________, into devitalised
tissue, such as exists following severe trauma to a leg
```
Clostridium perfringens
195
```
Management Clostridium perfringens
• Refer immediately to surgical centre for
debridement
• Start _____
•______ if available
```
benzylpenicillin 2.4 g IV, 4 hourly + clindamycin
Hyperbaric oxygen
196
Botulism is food poisoning caused by the neurotoxin
| of _____
Clostridium botulinum
197
Suspect botulism if cranial nerve weakness
| with normal sensation. ______ and _______ quickly develop
General muscle paralysis and
| prostration
198
Mycoplasma Tx
Adolescents and young adults:
treat with _____
or
with _____
doxycycline (first line) 200 mg statim then
100 mg daily for 14 days
roxithromycin 300 mg (o) daily for 14 days
199
* Related to cooling systems in large buildings
| * Incubation 2–10 days
Legionella pneumophila (legionnaire disease)
200
Tx of Legionella
Patients can become very prostrate with
complications—treat with _______
azithromycin (o or IV)
or erythromycin (IV or o) plus (if very severe) add
ciprofloxacin or rifampicin for 14 to 21 days
