Passmedicine - Infection Flashcards
1
Q
What kind of bacteria is staph aureus?
A
Facultative anaerobe
Gram positive cocci
Catalase +ve
2
Q
How do most staph aureus strains have resistance to penicillin?
A
Beta-lactamase production
3
Q
How is resistance to methiillin usually mediated by?
A
Mec operon (penicillin binding protein is altered to be resistant to methicillin)
4
Q
What kind of bacteria is strep pyogenes?
A
Gram positive
Chain forming
Lancefield group A (produces beta-haemolysis on blood agar)
Catalase negative
5
Q
What superantigens can strep pyogenes release? What can this superantigen result in?
A
Pyogenic exotoxin A which –> scarlet fever
6
Q
What kind of antibiotic is used for strep pyogenes infections?
A
Penicillin/macrolides
7
Q
What kind of bacteria is E. coli?
A
Gram negative rod
Facultative anaerobe, non-sporing
8
Q
What is the mechanism of action of enterotoxigenic E. coli?
A
Produces enterotoxin that results in a large volume fluid secretion into the gut (via cAMP activation)
9
Q
What is the mechanism of action of enteropathogenic E. coli?
A
Binds to intestinal cells + causes structural damage –> large volume diarrhoea and fever
10
Q
What kind of bacteria is c. jejuni?
A
Gram negative, non-sporulating
11
Q
What kind of symptoms does c. jejuni infection cause?
A
Diffuse diarrhoea
RIF pain
12
Q
What antibiotic should be given for c. jejuni infection?
A
Usually self-limiting so does not require antibiotics
Quinolones often rapidly effective
13
Q
What kind of bacteria is H. pylori?
A
Gram negative, helix shaped rod, microaerophilic
Flagellated
14
Q
What enzyme do h. pylori produce?
A
Hydrogenase which derives energy from hydrogen released by intestinal bacteria
15
Q
How can h. pylori cause ulcers?
A
Secretes urase which breaks down gastric urea –> CO2 and ammonia –> bicarbonate which neuralises gastric acid (so stomach produces more acid)
16
Q
Where does h. pylori most commonly colonate?
A
Gastric antrum
17
Q
What patients get gastric ulcers + which patients get duodenal ulcers with h. pylori infections?
A
If colonises antrum - irritation leads to increased gastrin release + higher levels of gastric acid –> duodenal ulcers
More diffuse infection –> gastric acid levels lower and ulcers develop by local tissue damage from h. pylori –> gastric ulcers
18
Q
How is h. pylori infection diagnosed?
A
Serology
19
Q
What is the standard active TB therapy?
A
First 2 months:
rifampicin, isoniazid, pyrazinamide, ethambutol
Next 4 months:
rifampicin, isoniazid
20
Q
What is the treatment of latent TB?
A
3 months isoniazid (with pyridoxine) + rifampicin OR 6 months of isoniazid (with pyridoxine)
21
Q
What is the treatment of meningeal TB?
A
Treat for 12 months with steroids
22
Q
Who may have to undergo directly observed therapy (with 3x weekly dosing regimen) for TB?
A
Homeless with active TB
Patients who are likely to have poor concordance
All prisoners with active/latent TB
23
Q
Visual acuity should be checked before starting what TB drug?
A
Ethambutol
24
Q
What are features of genital herpes?
A
Painful genital ulceration
Urinary retention may occur
25
How is genital herpes managed?
Oral aciclovir
26
What is the management of primary attack of herpes during pregnant?
Elective c-section >28 weeks
| Supressive oral aciclovir until delivery
27
How is transmission of herpes to a baby in a women with recurrent herpes minimised?
Treatment with suppressive therapy until delivery
NB risk of transmission to baby is low
28
What is EBV aka?
Herpesvirus 4
29
What is the most common cause of infectious mononucleosis?
EBV
Less common causes include CMV, HHV-6
30
What classic triad of symptoms is seen in 98% of IM patients?
Sore throat
Pyrexia
Lympadenopathy
31
What other features can be seen in IM?
Malaise, anorexia, headache
Palatal petechiae
Splenomegaly (may predipose to splenic rupture)
Hepatitis
Lymphocytosis
Haemolytic anaemia secondary to cold agglutins
Maculopapular, pruritic rash develops in 99% of IM patients who take ampicillin/amoxicillin
32
How long do symptoms of IM typically take to resolve?
2-4 weeks
33
How is IM diagnosed?
Heterophil antibody test (monospot)
NICE recommend this + FBC in 2nd week of illness to confirm diagnosis
34
How is IM managed?
Supportive - rests, avoid alcohol, simple analgesia, hydration
35
What must those with IM avoid?
Contact sports for 8 weeks after having glandular fever to reduce risk of splenic rupture
36
List the live attenuated vaccines
```
BCG
measles, mumps, rubella (MMR)
influenza (intranasal)
oral rotavirus
oral polio
yellow fever
oral typhoid
```
37
List the inactivated vaccines
rabies
hepatitis A
influenza (intramuscular)
38
List the toxoid vaccines (inactivated toxins)
tetanus
diphtheria
pertussis
39
What is a subunit vaccine?
Only part of the pathogen is used to generate an immunogenic response
40
What is a conjugate vaccine?
A vaccine that links the immunogenic bacterial polysaccharide outer coats to the proteins to make them more immunogenic
41
List some conjugate vaccines
Pneumococcus
Haemophilus
Meningococcus
42
List some subunit vaccines
Hep B
| HPV
43
What does the Hep B vaccine contain?
HbsAg adsorbed onto aluminium hydroxide adjuvant
44
What groups are at risk from HIV?
IVDAs
| Those who received a blood transfusion prior to 1991
45
What kind of virus is hep C?
RNA flavivirus
46
What is the risk of transmission of hep C during a needlestick injury?
2%
47
What is the risk of vertical transmission of hep C?
6%
48
Is breastfeeding CI in hep C positive mothers?
No
49
What are the features of hep C infection?
Usually asymptomatic
| May experience: rise in aminotransferases/jaundice, fatigue, arthalgia
50
What is the investigation of choice to diagnose acute hep C infection?
HCV RNA
51
What is the outcome of a hep C infection?
15-45% clear it after an acute infection
| 55-85% go on to develop a chronic infection
52
Define chronic hepatitis C
Persistence of HCV RNA in the blood for 6 months
53
What are potential complications of chronic hep C?
```
Arthalgia, arthritis
Sjogren's
Cirrhosis
Heptocellular cancer
Cryoglobulinaemia (usually type II)
Porphyria cutanae tarda
Membranoproliferative GN
```
54
How is chronic hep C infection treated?
Depends on viral genotype (test prior)
| Combination of protease inhibitors (e.g. daclatasvir + sofosbuvir or sofosbuvir + simeprevir) with or without ribavirin
55
What are SEs of ribavirin?
Haemolytic anaemia
Cough
Teratogenic (do not become pregnant <6m after use)
56
What is the best way to assess response to treatment of hep C infection?
Viral load
57
What types of HPV generally cause genital warts?
6 and 11
58
How are genital warts treated?
First line
Topical podophyllum - multiple/non-keratinised
Cryotherapy - solitary/keratinised
Second line
Imiquimod (topical cream)
59
What is the most common cause of oesophagitis in HIV patients?
Oesophageal candidiasis
60
What CD4 count is oesophagal candidiasis typically seen in?
<100
61
What are typical symptoms of oesophageal candidiasis?
Dysphagia
| Odynophagia
62
How is oesophageal candidiasis treated?
Fluconazole, itraconazole
63
What kinds of infections can E. coli cause?
Diarrhoea
UTI
Neonatal meningitis
64
What are the different E. coli antigens
A - O
B - K
C - H?
A - O = lipopolysaccharide layer
B - K = capsule (usually what causes neonatal meningitis)
C - H = flagellin
65
What does mycoplasma pneumoniae tend to cause?
An atypical pneumonia in younger patients
66
What are characteristic complications associated with mycoplasma pneumonia?
```
Erythema multiforme
Cold autoimmune haemolytic anaemia
Meningoencephalitis, GBS
Bullous myringitis
Pericarditis/myocarditis
GI - hepatitis/pancreatitis
Acute GN
```
67
What are features typical of a mycoplasma pneumonia?
Prolonged + gradual onset
| Flu like symptoms preceding a dry cough
68
What do you see on CXR in mycoplasma pneumonia?
Bilateral consolidation
69
What is bullous myringitis?
Painful vesicles on the tympanic membrane
70
How is mycoplasma pneumonia generally diagnosed?
Mycoplasma serology
| also have a positive cold agglutination test
71
How is mycoplasma pneumonia managed?
Doxycycline or macrolide
72
What kind of bacteria are salmonella spp?
Aerobic, gram negative robs
Remember - these are not normally gut commensals
73
What bacteria causes typhoid?
Salmonella typhi
74
What bacteria causes paratyphoid?
Salmonella paratyphi
75
How is typhoid transmitted?
Faecal-oral
76
What are the clinical features of typhoid/paratyphoid?
Systemic upset (headache, fever, arthalgia)
Relative bradycardia
Ab pain, distension
Constipation (more common in typhoid) or diarrhoea
Rose spots on the trunk (more common in paratyphoid)
77
What are complications of typhoid/paratyphoid?
```
Osteomyelitis (esp. in sickle cell disease)
GI bleed/perforation
Meningitis
Cholecystitis
Chronic carriage
```
78
What antibiotic can be used to treat typhoid/paratyphoid?
Ciprofloxacin
79
What is the first line treatment of syphillis?
IM benzylpen
Alt: doxycycline
80
What reaction is sometimes seen after treatment of syphillis?
Jarisch-Herxheimer
(fever, tachycardia, rash after first dose)
Thought to be due to release of endotoxins following bacterial death (occurs few hours after treatment)
81
How is Jarisch-Herxheimer treated?
Antipyretics
82
Following splenectomy, what infections are patients particularly at risk of?
Pneumococcus
Haemophilus
Meningococcus
83
When should patients due to undergo splenectomy receive their vaccinations?
2 weeks prior to the operation
84
What vaccinations should those undergoing splenectomy receive?
Hib, meningitis A and C
Annual flu jab
Pneumococcal every 5 years
85
What antibiotic prophylaxis should those who have undergone splenectomy receive?
Penicillin V
86
What are indications for splenectomy?
Trauma
Spontaneous rupture, e.g. EBV
Hypersplenism - hereditary spherocytosis, elliptocytosis etc..
Malignancy - lymphoma/leukaemia
Splenic cysts, hydatid cysts, splenic abscesses
87
What are complications of splenectomy?
Haemorrhage
Pancreatic fistula (due to damage to pancreatic tail)
Thrombocytosis
Encapsulated bacteria infection (e.g. strep pneumoniae, Hib, Neisseria meningitidis)
88
What changes will occur in the body post-splenectomy?
Platelets rise
Howell-jolly bodies appear
Target cells, Pappenheimer bodies
89
Post-splenectomy sepsis typically occurs with what organisms?
Encapsulated organisms
90
What pathogen causes bronchiolitis?
RSV
91
What pathogen causes croup?
Parainfluenza virus
92
What pathogen causes the common cold?
Rhinovirus
93
What pathogen causes flu?
Influenza
94
What pathogen most commonly causes community acquired pneumonia?
Strep pneumoniae
95
What pathogen most commonly causes bronchiectasis exacerbations?
Hib
96
What pathogen causes acute epiglottitis?
Hib
97
What pathogen causes pneumonia, especially following flu?
Staph aureus
98
What organisms most commonly cause an atypical pneumonia?
Mycoplasma pneumoniae - flu symptoms --> dry cough
| Legionella pneumoniae - causes dry cough, lymphopenia, deranged LFTs, hyponatraemia
99
What classically spreads legionella?
Air conditioning systems
100
What is a common cause of pneumonia in HIV patients?
PJP
101
What are typical features of a PJP pneumonia?
Few chest signs, exertional SoB
102
What are typical features of pulmonary TB?
Cough
Night sweats
Weight loss
103
What is meant by a 'notifiable disease'?
Disease that the proper officer at the local health protection team needs to be notified about
104
What are notable exceptions to notifiable diseases?
HIV
105
List 5 notifiable diseases
```
Acute encephalitis
Acute infectious hepatitis
Acute meningitis
Acute poliomyelitis
Anthrax
Botulism
Brucellosis
Cholera
Diphtheria
Enteric fever (typhoid or paratyphoid fever)
Food poisoning
Haemolytic uraemic syndrome (HUS)
Infectious bloody diarrhoea
Invasive group A streptococcal disease
Legionnaires Disease
Leprosy
Malaria
Measles
Meningococcal septicaemia
Mumps
Plague
Rabies
Rubella
SARS
Scarlet fever
Smallpox
Tetanus
Tuberculosis
Typhus
Viral haemorrhagic fever (VHF)
Whooping cough
Yellow fever
```
106
What kind of virus is CMV?
Herpes virus
107
It is thought that ___% of people have been exposed to CMV virus, but it only causes disease in those who are...
50%
| Immunocompromised, e.g. HIV/following organ transplant
108
What do cells infected with CMV look like?
Owl's eye appearance due to intranuclear inclusion bodies
109
What are features of congenital CMV infection?
```
Growth retardation
Pinpoint petechial blueberry muffin skin lesions
Microencephaly
Sensorineural deafness
Encephalitis (seizures)
Hepatosplenomegaly
```
110
Who does CMV retinitis tend to develop in?
HIV patients with a low CD4 (<50)
111
How does CMV retinitis present?
Visual impairment, e.g. b blurred vision
112
What do you see on fundoscopy in CMV retinitis?
Multiple retinal haemorrhages and necrosis - pizza retina
113
What is the treatment of choice for CMV retinitis?
IV ganciclovir
114
What organism causes chancroid?
Haemophilus ducreyi
115
What are features of chancroid?
Painful genital ulcers (with sharply defined, ragged, undetermined border)
Unilateral, painful inguinal LN enlargement
116
What causes lymphogranuloma venereum?
Chlamydia trachomatis
117
What are the three stages of lymphogranuloma venereum?
1 - small painless pustule which later forms an ulcer
2 - painful inguinal lympadenopathy
3 - proctocolitis
118
How is LVG treated?
Doxycycline
119
What organisms typically cause cellulitis?
Strep pyogenes
| Staph aureus
120
What are features of cellulitis?
Erythema, pain, swelling
Systemic upset, e.g. fever
Commonly occurs on shins
121
What classification is used to guide how we manage patients with cellulitis?
Eron
122
Eron I
No signs of systemic toxicity
| No uncontrolled co-morbs
123
Eron II
Systemically unwell
| Systemically well with co-morb
124
Eron III
Significant systemic upset, e.g. acute confusion, tachycardia, tachynoea, hypotension or unstable co-morbs
125
Eron IV
Sepsis or severe life-threatening infection, e.g. necrotizing fasciitis
126
What patients with cellulitis should be admitted for IV antibiotics?
Eron III or IV
Severe/rapidly deteriorating cellulitis, e.g. large areas of skin
Very young (<1y) or frail
Immunocompromised
Has significant lymphoedema
Has facial cellulitis/periorbital cellulitis
127
How are Eron II patients managed?
Can be treated with IV antibiotics in the community
128
How are all other patients (Eron I) with cellulitis managed?
Oral antibiotics
| Flucloxacillin 1st line (clarithromycin, erythromycin (in pregnancy), doxcycline if penicillin allergic)
129
What antibiotic should be given to those with severe cellulitis?
Co-amoxiclav, cefuroxime, clindamycin, ceftriaxone
130
When is trimethoprim a risk for teratogenicity?
First trimester
131
What patients should be screened for MRSA?
All patients awaiting elective admissions
| Emergency admission
132
How should a patient be screened for MRSA?
Nasal swab and skin lesions/wounds
| Wipe inside rim of nose for 5 seconds
133
How is MRSA supressed from a carrier once identified?
Nose - mupirocin 2% in white soft paraffin tds for 5 days
| Skin - chlorhexidine gluconate od 5 days (apply all over)
134
What antibiotics can be used to treat MRSA infections?
Vancomycin
Teicoplanin
Linezolid (reserve for resistant cases)
135
What organisms can cause community acquired pneumonia?
Strep pneumoniae
H. influenzae
Staph aureus
Viruses
136
What organism classically causes pneumonia in alcoholics?
Klebsiella pneumoniae
137
What are the characteristic features of a pneumococcal pneumoniae?
Rapid onset
High fever
Pleuritic chest pain
Herpes labialis
138
What causes kaposi's sarcoma?
HHV-8
139
How does kaposi sarcoma present?
Purple papules/plaques on skin or mucosa which may ulcerate
| Respiratory involvement may --> massive haemoptysis + pleural effusion
140
How is kaposi sarcoma treated?
Radiotherapy + resection
141
What causes amoebiasis?
Entamoeba histolytica
142
What kinds of syndromes can amoebiasis lead to?
Amoebic dysentry
| Amoebic liver abscess
143
How is amoebic dysentry treated?
Metronidazole
144
What is an amoebic liver abscess classically like?
Single mass in right lobe filled with 'anchovy sauce'
145
What are clinical features of an amoebic liver abscess?
Fever
| RUQ pain
146
Give examples of tetracyclines
Doxycyline
| Tetracycline
147
What is the mechanism of action of tetracyclines?
Protein synthesis inhibitors
148
What is the commonest mechanisms of resistance against tetracyclines?
Increased efflux of the bacteria by plasmid-encoded transport pumps, ribosomal protection
149
What are indications for tetracycline use?
Acne vulgaris
Lyme disease
Chlamydia
Mycoplasma pneumoniae
150
What are notable AEs associated with tetracyclines?
Discolouration of teeth - do not use before age 12
Photosensitivity
Anigioedema
Black hairy tongue
151
What are important CIs to the use of tetracyclines?
Pregnancy + breastfeeding due to discolouration of the neonates teeth
152
What malignancies are associated with EBV?
Burkitt's lymphoma
Hodgkin's lymphoma
Nasopharyngeal carcinoma
HIV-associated central nervous system lymphomas
153
What non-malignant condition is EBV associted with?
Hairy leukoplakia
154
What is leprosy?
Granulomatous disease primarily affecting the peripheral nerves and skin
155
What causes leprosy?
Mycobacterium leprae
156
What are the clinical features of leprosy?
Patches of hypopigmented skin typically affecting the buttocks, face, extensor surfaces of limbs
Sensory loss
157
What determines the type of leprosy a patient gets?
Low degree of cell mediated immunity --> lepromatous leprosy = extensive skin involvement, symmetrical nerve involvement
High degree of cell mediated immunity --> tuberculoid leprosy = limited skin disease, asymmetric nerve involvement
158
How is leprosy managed?
Triple therapy - rifampicin, dapsone, clofazimine
159
Gram positive cocci =
Staph, strep
160
Gram negative cocci =
Neisseria meningitis/gonorrhoeae
| Moraxella catarrhalis
161
Gram positive bacilli =
```
ABCD L
Actinomyces
Bacillus anthracis
Clostridium
Diphtheria
Listeria monocytogenes
```
162
Gram negative rods =
```
E. coli
H. influenzae
Pseudomonas aeruginosa
Salmonella spp.
Shigella spp.
C. jejuni
```
163
What diseases does parovirus B19 cause?
Erythema infectiosum (slapped cheek syndrome)
164
How does slapped cheek syndrome present?
Mild feverish illness +/- bright, red rash over the cheeks
Child feels better as rash appears
165
How long does the rash in slapped cheek syndrome tend to take to go away?
Usually peaks after a week and then fades
| BUT for some months after, a warm bath, sunlight, heat/fever may trigger its recurrence
166
How is slapped cheek managed?
Usually self-limiting
167
Is school exclusion with slapped cheeky req?
No as once the rash appears the child is no longer infectious
168
In adults what can parovirus B19 cause?
An acute arthritis
169
What is the most important thing to remember about parovirus B19?
Can affect unborn baby in first 20 weeks
If women exposed before 20 weeks must have IgM and IgG checked
170
When is someone with parovirus B19 infectious?
3-5 days before the rash appears
171
How might parovirus B19 infection present in immunocompromised patients?
Pancytopenia
172
How might parovirus B19 infection present in sickle cell patients?
Aplastic crises (parovirus B19 supresses erythropoiesis for about a week)
173
What are the two types of necrotizing fasciitis?
1 - caused by mixed anaerobes + aerobes (often occurs post-surgery in DM) - most common
2 - strep pyogenes most common cause
174
What are the clinical features of necrotizing fasciitis?
Acute onset
Painful, erythematous lesion develops
Often presents as rapidly worsening cellulitis with pain out of keeping with physical features
Extremely tender over underlying tissue
175
How is necrotizing fasciitis managed?
Urgent surgical referral for debridement
| IV antibiotics
176
What is a spinal epidural abscess (SEA)?
Collection of pus superficial to the dura mater of the spinal cord
177
Why is SEA an emergency?
Requires urgent treatment to avoid progressive spinal cord damage
178
Define abscess
Collection of pus encapsulated by a pyogenic membrane
179
How can bacteria enter the epidural space to cause SEA?
Contiguous spread from adjacent structures, e.g. discitis
Haematological spread, e.g. from bacteraemia from IVDU
Direct infection, e.g. post-spinal surgery
180
What is a major risk factor for SEA?
Immunosupression, e.g. HIV, DM, alcoholism, chemotherapy, steroids etc.
181
What organism most commonly is responsible for SEA?
Staph aureus
182
How do patients with SEA typically present?
Fever
Back pain
Focal neurological deficits according to the segment of cord affected
183
What investigations should be done in suspected SEA?
Bloods - inflammatory markers, HIV, Hep B, Hep C, coagulation, group and save
Blood cultures
Infection screen (incl. CXR and urine culture)
MRI whole spine
184
Why do you need to MRI the whole spine in SEA?
Skip lesions may be present
185
If the primary source of infection in SEA is not clear what further investigations may be required?
Dental x-rays, ECG etc.
186
What is the management of SEA?
Long term broad spectrum antibiotics, later refined based on cultured results
Large/compressive abscess or significant neurological deficits/not responding to antibiotics alone --> surgery
187
What are potential complications of chlamydia?
```
Epididymitis
PID
Endometritis
Increased risk of ectopic
Infertility
Reactive arthritis
Perihepatitis (Fitz-Hugh-Curtis syndrome)
```
188
When should chlamydia testing be carried out?
2 weeks after a possible exposure
189
How is chlamydia managed?
7d doxycycline or azithromycin (single dose) 1g
190
What is the main technique used to test for latent TB?
Mantoux test
191
In which people would you use interferon gamma blood test to test for latent TB?
Then the mantoux test is positive/equivocal
| In those where the tuberculin test may be falsely negative
192
What does the mantoux test involve?
0.1ml of 1:1, 000 purified protein dervative injected intradermally
Result read 2-3d later
193
How do you interpret a mantoux test?
Diam <6mm - negative (no significant hypersensitivity to tuberculin protein - never been exposed to TB/BCG)
Diam 6-15mm - positive (hypersensitive to tuberculin protein - do not need BCG as have had it before/had TB before)
Diam >15mm - strongly positive (strongly hypersensitive to tuberculin - suggests TB infection)
194
What things may cause a false negative mantoux test?
```
Miliary TB
Sarcoidosis
HIV
Lymphoma
Very young age (<6m)
```
195
What test for TB is no longer used in the UK?
Heaf test
196
When should someone receive their tetanus vaccinations?
```
2 months
3 months
4 months
3-5 years
13-18 years
```
This gives long term protection against tetanus
197
What wounds are considered to be at high risk of leading to tetanus?
```
Compound fractures
Delayed surgical intervention (>6h)
Significant degree of devitalised tissue
Wounds contaminated with soil
Wounds containing FBs
Wounds/burns in people with sepsis
```
198
How should wounds at high risk of tetanus be managed?
IM human tetanus Ig regardless of whether they have been vaccinated
If vaccination history incomplete/unknown give dose of tetanus vaccine as well
199
```
What are the following CSF characteristics:
A. appearance
B. glucose
C. protein
D. white cells
In bacterial meningitis?
```
A. appearance: cloudy
B. glucose: low (<1/2 plasma)
C. protein: high
D. white cells: 10-5, 000 polymorphs
200
```
What are the following CSF characteristics:
A. appearance
B. glucose
C. protein
D. white cells
In viral meningitis?
```
A. appearance: clear/cloudy
B. glucose: 60-80% plasma
C. protein: normal/raised
D. white cells: 15-1, 000 lymphocytes
Exceptions - mumps and herpes encephalitis --> low glucose
201
```
What are the following CSF characteristics:
A. appearance
B. glucose
C. protein
D. white cells
In tuberculous meningitis?
```
A. appearance: slight cloudy, fibrin web
B. glucose: low (<1/2 plasma)
C. protein (high)
D. white cells: 10-1, 000 lymphocytes
202
What else can you do to the CSF if you suspect tuberculous meningitis?
ZN stain (but only sensitive in 20%) so PCR sometimes used
203
What causes cholera?
Gram negative vibro cholerae
204
What are features of cholera?
Rice water diarrhoea (profuse)
Dehydration
Hypoglycaemia
205
How is cholera managed?
Oral dehydration therapy
| Doxycyline, ciprofloxacin
206
Where is chancroid usually acquired?
In the tropics
207
In post-splenectomy patients what organism does penicillin V prophylaxis not protect against?
H. influenzae (due to production of beta-lactamases)
208
What vaccines should not be given to immunocompromised patients?
Live attenuated ones - e.g. BCG
209
What causes tetanus?
Tetanospasmin exotoxin released from clostridium tetani
210
Where are tetanus spores found?
Soil
211
How does tetanospasmin cause tetanus?
Prevents release of GABA
212
What are features of tetanus?
```
Prodrome fever, lethargy, headache
Trismus
Risus sardonicus
Opishtotonus (arched back, hyperextended neck)
Spasms, e.g. dysphagia
```
213
How is tetanus manaed?
Supportive, e.g. muscle relaxants, ventilatory support
IM human tetanus Ig for high risk wounds
Metronidazole is first line antibiotic
214
What is the pathophysiology of mycobacterium tuberculosis?
Macrophages migrate to regional LNs (lung lesion + affected LNs = Ghon complex)
Leads to formation of granuloma (collection of epitheloid histiocytes)
Caseous necrosis in centre
Inflammatory response mediated by T4HS
In healthy people, disease may be contained, in immunocomp patients disseminated (miliary TB) may occur
215
Why can't you use normal stains to view mycobacterium tuberculosis?
It membrane is waxy and prevents binding with normal stains
216
What stain is typically used to see TB?
Ziehl Neelsen stain
217
What is the recommended antibiotic therapy for exacerbations of COPD?
Amoxicillin
| Tetracycline or clarithromycin
218
What is the recommended antibiotic therapy for uncomplicated CAP?
Amoxicillin
(doxycyline/clarithromycin if penicillin allergic)
Add in fluclox if staph suspected e.g. flu
219
What is the recommended antibiotic therapy for pneumonia caused by atypical pathogens?
Clarithromycin
220
What is the recommended antibiotic therapy for hospital acquired pneumonia?
Within 5d of admission - co-amoxiclav or cefuroxime
>5d after admission - piperacillin with tazobactam or broad spectrum cephalosporin (e.g. ceftazidime) or a quinolone (e.g. ciprofloxacin)
221
What is the recommended antibiotic therapy for a lower UTI?
Trimethoprim or nitrofuratoin
| Alt: amoxicillin
222
What is the recommended antibiotic therapy for acute pyelonephritis?
Broad spectrum cephalosporin or quinolone
223
What is the recommended antibiotic therapy for acute prostatitis?
Quinolone or trimethoprim
224
What is the recommended antibiotic therapy for impetigo?
Topical fusidic acid
| Oral fluclox or erythromycin if widespread
225
What is the recommended antibiotic therapy for celullitis?
Flucloxacillin (clarithromycin, erythromycin or doxy if penicillin allergic)
226
What is the recommended antibiotic therapy for cellulitis near nose or eyes?
Co-amoxiclav (clarithromycin, + metronidazole if penicillin-allergic)
227
What is the recommended antibiotic therapy for erysipelas?
Flucloxacillin (clarithromycin, erythromycin or doxycycline if penicillin-allergic)
228
What is the recommended antibiotic therapy for animal/human bite?
Co-amoxiclav (doxycycline + metronidazole if penicillin-allergic)
229
What is the recommended antibiotic therapy for mastitis whilst breast feeding?
Flucloxacillin
230
What is the recommended antibiotic therapy for throat infections?
Phenoxymethylpenicillin (erythromycin alone if penicillin-allergic)
231
What is the recommended antibiotic therapy for sinusitis?
Amoxicillin or doxycycline or erythromycin
232
What is the recommended antibiotic therapy for otitis media?
Amoxicillin (erythromycin if penicillin-allergic)
233
What is the recommended antibiotic therapy for otitis externa?
Flucloxacillin (erythromycin if penicillin-allergic)
234
What is the recommended antibiotic therapy for periapical/periodontal absces?
Amoxicillin
235
What is the recommended antibiotic therapy for gingivitis (acute necrotizing ulcerative)?
Metronidazole
236
What is the recommended antibiotic therapy for gonorrhoea?
Intramuscular ceftriaxone
237
What is the recommended antibiotic therapy for chlamydia?
Doxycycline or azithromycin
238
What is the recommended antibiotic therapy for PID?
Oral ofloxacin + oral metronidazole or intramuscular ceftriaxone + oral doxycycline + oral metronidazole
239
What is the recommended antibiotic therapy for syphillis?
Benzathine benzylpenicillin or doxycycline or erythromycin
240
What is the recommended antibiotic therapy for BV?
Oral or topical metronidazole or topical clindamycin
241
What is the recommended antibiotic therapy for c. diff infections?
First episode: metronidazole
| Second or subsequent episode of infection: vancomycin
242
What is the recommended antibiotic therapy for campylobacter enteritis?
Clarithromycin
243
What is the recommended antibiotic therapy for salmonella?
Ciprofloxacin
244
What is the recommended antibiotic therapy for shigellosis?
Ciprofloxacin
245
What baseline tests are required before someone starts anti-TB therapy?
LFTs as all drugs are hepatotoxic
UE
Baseline visual assessment (ethambutol)
FBC for platelet count
246
What are the features of primary syphillis?
Chancre - painless ulcer at site of sexual contact
| Local non-tender lymphadenopathy
247
What are features of secondary syphillis?
6-10w post primary infection
Systemic symptoms -fever, lymphadenopathy
Rash on trunk, palsm and soles
Buccal snail track ulcers
Condylomata lata (painless, warty lesions on genitalia)
248
What are features of tertiary syphillis?
```
Gumma (granulomatous lesions of skin and bones)
Ascending aorta aneurysm
General paralysis of the insane
Tabes dorsalis
Argyll-Robertson pupil
```
249
What are features of congenital syphillis?
Blunted upper incisor teeth (Hutchison's teeth), mulberry molars
Rhagades (linear scars at angle of mouth)
Keratitis
Saber shins
Saddle nose
Deafness
250
What causes legionnaire's disease?
Intracellular bacterium Legionella pneumophilia
251
Why does legionella typically spread?
Colonizes water tanks or can spread through AC systems
252
What are features of legionnaire's disease?
```
Flu like symptoms + fever
Dry cough
Relative bradycardia
Confusion
Lymphopaenia
Hyponatraemia
Derranged LFTs
Pleural effusion 30%
```
253
How is legionnaire's disease diagnosed?
Urinary antigen
254
How is legionnaire's disease treated?
Erythromycin/clarithromycin
255
What is the most common cause of viral encephalitis in the adult population?
HSV
256
What features are suggestive of a viral encephalitis?
Sudden change in behaviour
Fever
Seizures
257
What kind of bacteria is pseudomonas aeruginosa?
Aerobic gram negative rod
258
What kind of infections does pseudomonas cause?
Chest infections (esp. in CF)
Skin - burns, chronic wound infections
Otitis externa (esp in DM)
UTIs
259
What is the most common organism found in central line infections?
Staph epidermidis
260
What are the main differences between staph aureus and staph epidermidis?
Aureus - coagulase +ve, skin infections, asbcesses, OM, toxic shock syndrome
Epidermidis - coagulase -ve, central line infections, IE
261
How is BV treated in pregnancy?
Oral metronidazole still
262
What PEP is used for hep A?
Human normal immunoglobulin or hep A vaccine
263
What PEP is used for Hep B?
Vaccinated (HBsAg positive) - booster dose of HBV vaccine
Non-vaccinated/non-responder - hepatitis B Ig and vaccine
In process of being vaccinated - accelerated course of HBV
264
What PEP is used for hep C?
Monthly PCR - if seroconversion then inferferon +/i ribavirin
265
What PEP is used for HIV?
Low risk incidents, e.g. human bites don't req. PEP
Combination of ARTs ASAP (within 72h) for 4 weeks
Serological testing 12 weeks after completion of PEP
266
What PEP is used for VZV?
VZIg for Ig negative pregnant women/immunosupressed
267
What is the risk of transmission of Hep B from a needlestick injury?
20-30%
268
What is the risk of transmission of Hep C from a needlestick injury?
0.5-2%
269
What is the risk of transmission of HIV from a needlestick injury?
0.3%
270
What herpes virus mostly causes oral lesions?
HSV1
271
What herpes virus mostly causes genital herpes?
HSV2
272
How is herpes gingivostomatitis managed?
Oral aciclovir
| Chlorhexidine mouthwash
273
How are cold sores managed?
Topical aciclovir
274
How is genital herpes managed?
Oral aciclovir (if frequent exacervations may require long term aciclovir)
275
What is classical of the fever in malaria?
It comes on alternating days
Nb other symptoms of malaria include headache, myalgia, hepatomegaly
276
What investigations are recommended by NICE in suspected meningitis?
```
FBC
CRP
Coagulation screen
Blood culture
Whole blood PCR
Blood glucose
Blood gas
LP if no signs of raised ICP
```
277
How is suspected meningitis managed?
Admit to hospital
| If in GP + meningococcal disease suspected --> IM benzylpenicillin + transfer to hospital
278
What initial empirical therapy is given for meningitis in those aged <3 months?
IV cefotaxime + amoxicillin
279
What initial empirical therapy is given for meningitis in those aged 3 months - 50 years?
IV cefotaxime
280
What initial empirical therapy is given for meningitis in those aged >50 years?
IV cefotaxime + amoxicillin
281
What therapy is given for meningococcal meningitis?
IV benzylpenicillin or cefotaxime
282
What therapy is given for meningitis for those with pneumococcal meningitis?
IV cefotaxime
283
What therapy is given for meningitis due to H. influenzae?
IV cefotaxime
284
What therapy is given for meningitis due to listeria?
IV amoxicillin + gentamicin
285
What drug (aside from antimicrobials) should be given in meningitis management and why?
IV dexamethasone to reduce risk of neurological sequelae
286
What drug should be used to treat meningitis if the patient is allergic to penicillin or cephalosporins?
Chloramphenicol
287
For what kind of meningitis must you offer household/close contacts prophylaxis? What is this prophylaxis?
Meningococcal
(If been in contact within 7 days of onset)
Oral ciprofloxacin (1st line) or rifampicin
Offer meningococcal vaccine to close contacts when serotype results are available
288
What are the most common causes of meningitis in those aged 0-3 months?
Group B Streptococcus (most common cause in neonates)
E. coli
Listeria monocytogenes
289
What are the most common causes of meningitis in those aged 3 months - 6 years?
Neisseria meningitidis
Streptococcus pneumoniae
Haemophilus influenzae
290
What are the most common causes of meningitis in those aged 6 years - 60 years?
Neisseria meningitidis
| Streptococcus pneumoniae
291
What are the most common causes of meningitis in those aged >60 years?
Streptococcus pneumoniae
Neisseria meningitidis
Listeria monocytogenes
292
What is a common cause of bacterial meningitis in those who are immunosupressed?
Listeria monocytogenes
293
Which STI is a 'strawberry cervix' associated with?
Trichomonas vaginalis
294
How is uncomplicated falciparum malaria treated?
1st line - Artemisinin based combination therapies
295
How is complicated falciparum malaria treated?
```
IV artesunate
(parasite >10% - consider exchange transfusion)
```
296
What is rabies?
Viral disease that causes an acute encephalitis
297
What kind of virus causes rabies?
Lyssavirus
298
What kinds of bites can spread rabies?
Usually dog
| Others - bat, racoon, skunk
299
Following a bite how does the rabies virus spread in the body?
Up nerve axons towards the central nervous system
300
What are the clinical features of rabies?
Prodrome - headache, fever, agitation
Hydrophobia - water provoking muscle spasms
Hypersalivation
301
What kind of bodies are seen in neurons infected with rabies?
Negri bodies (cytoplasmic inclusion bodies)
302
How should animal bites in at risk countries (of rabies) be managed?
Wash wound
Vaccinated - give further 2 doses of vaccine
Not vaccinated - human rabies Ig + full vaccination course (administer locally around wound)
303
What is the prognosis of rabies?
Untreated disease is nearly always fatal
304
What is the first line treatment of animal bites?
Co-amoxiclav
305
What individuals are offered a BCG?
All infants (0-12m) living in areas where annual incidence of TB 40/100, 000+ or with a grandparent/parent who was born in a country where the incidence of TB is that
Previously unvaccinated tuberculin -ve contacts of cases of respiratory TB
Previously unvaccinated tuberculin negative new entrants under 16 who were born/lived (>3m) in a country with annual TB incidence 40/100, 000+
Healthcare workers
Prison staff
Staff of care home for the elderly
Those working with the homeless
306
What does the BCG vaccine contain?
Live attenuated mycobacterium bovis
307
What must you have prior to having a BCG?
Tuberculin skin tests (unless younger than 6 and no contact with TB)
308
What can BCG not be given at the same time as?
Other live vaccines (leave 4 week interval)
309
What are contraindications to getting a BCG?
```
Prev. BCG
Hx of TB
HIV
Pregnancy
>35 years (no evidence of efficiacy)
Positive tuberculin test
```
310
What are the two tuberculin tests?
Heaf and mantoux
311
When is it appropriate to perform stool microbiological investigations for a child with diarrhoea?
1. Suspected septicaemia
2. Blood/mucous in stool
3. Child is immunocompromised
312
Define PUO
Fever >3 weeks with resists diagnosis after 1 week in hospital
313
What are causes of PUO
Neoplasia - lymphoma, hypernephroma, preleukaemia, atrial myxoma
Infections - TB, abscess
Connective tissue disorders
314
What is the quickest way to determine lactate levels?
ABG or VBG
315
What is co-trimaxazole a mix of?
Trimethoprim and sulfamethoxazole
316
Drugs that end in -navir are from what class of drugs?
Protease inhibitors
317
Drugs that end in -gravir are from what class of drugs?
Integrase inhibitors
318
How is legionella pneumophilia best diagnosed?
Urinary antigen test
319
What is the single most effective single measure to reduce the incidence of MRSA?
Hand hygiene
320
What organism is responsible for causing toxoplasmosis?
Toxoplasma gondii
321
How does toxoplasmosis spread?
Protozoa infects via GIT, lungs or broken skin
| Its oocytes release trophozoites which migrate around the body, including to the muscle, eyes and brain
322
What is the usual reservoir for toxoplasma gondii?
Cat
323
What is a common presentation of toxoplasmosis?
IM type illness (fever, malaise, lymphadenopathy)
Less common manifestations include meningioencephalitis + myocarditis
324
How do you test for toxoplasmosis?
Ab test
| Sabin Feldman dye test
325
Who is treated for toxoplasmosis?
Those with severe infections/immunosupressed
326
What is the treatment of toxoplasmosis?
Pyrimethamine + sulphadiazine for 6 weeks (at least)
327
What causes congenital toxoplasmosis?
Transplacental spread from mother
328
What are features of congenital toxoplasmosis?
Microcephaly, hydrocephalus, cerebral calcification + choriodoretinitis
329
What family is the ebola virus from?
Filoviridae virus family
330
How does ebola spread?
Human to human transmission through broken skin or mucous membranes with blood, secretions, organs or other bodily fluids of infected people and surfaces contaminated with these fluids
331
What is the incubation period of ebola?
2-21 days
Only infectious once symptoms develop
332
What are the first symptoms of ebola?
Sudden onset fever, fatigue, muscle pain, headache, sore throat
333
What follows the initial symptoms of ebola?
```
Vomiting
Diarrhoea
Rash
Impaired kidney and liver function
Internal + external bleeding
```
334
In which patients should you consider a diagnosis of ebola?
Fever 37.5C+ or have hx of fever in past 24h AND have recently visited any of the affected areas in the last 21 days/cared for/come in contact with bodily fluids of someone strongly suspected/known to have VHF
335
How should ebola be managed?
Advise not to visit surgery
| Contact PHE
336
What is this history typical of?:
Bilateral conjunctivitis, bilateral calf pains, high fever in a sewage worker
Mild leptospirosis
337
What fluid therapy should be given to someone as part of the sepsis 6 bundle?
If >16y IV fluid resus with crystalloids 500ml STAT (over 15 min)
338
What causes giardiasis?
Flagellated protozoan giardia lamblia
339
How is giardia lamblia spread?
Faecal oral
340
What are the clinical features of giardiasis?
```
Often asymptomatic
Bloating, lethargy, ab pain
Flatulence
Non-bloody diarrhoea
Chronic diarrhoea, malabsorption, lactose intolerance
```
341
How is giardiasis treated?
Metronidazole
342
What happens if you take metronidazole with alcohol?
Disulfiram like reaction (flushing, nausea, vomiting, sweatiness, headache, palpitations)
343
How does metronidazole work?
Forms reactive cytotoxic metabolites inside bacteria
344
What is an aspergilloma?
Mass like fungus ball (mycetoma) which often colonises an existing lung cavity (e.g. secondary to TB, lung cancer etc.)
345
What are clinical features of an aspergilloma?
Usually asymptomatic
| Cough, haemoptysis
346
What does an aspergilloma appear like on CXR?
Rounded opacity
| Crescent sign may be present
347
Flu like symptoms, a dry cough, relative bradycardia and confusion. Blood tests show a hyponatraemia.
What is this a typical history of?
Legionnaire's disease
348
List antifungal agents
```
Azoles
Amphotericin B
Terbinafine
Griseofulvin
Flucytosine
Caspofungin
Nystatin
```
349
What is the mechanism of action of azoles?
Inhibits 14α-demethylase which produces ergosterol
350
What is the mechanism of action of amphotericin B?
Binds with ergosterol forming a transmembrane channel that leads to monovalent ion (K+, Na+, H+ and Cl) leakage
351
What is the mechanism of action of terbinafine?
Inhibits squalene epoxidase
352
What is the mechanism of action of griseofulvin?
Interacts with microtubules to disrupt mitotic spindle
353
What is the mechanism of action of flucytosine?
Converted by cytosine deaminase to 5-fluorouracil, which inhibits thymidylate synthase and disrupts fungal protein synthesis
354
What is the mechanism of action of capsofungin?
Inhibits synthesis of beta-glucan, a major fungal cell wall component
355
What is the mechanism of action of nystatin?
Binds with ergosterol forming a transmembrane channel that leads to monovalent ion (K+, Na+, H+ and Cl) leakage
356
How is nystatin normally administered?
Usually topical, e.g. for oral thrush as it is very toxic
357
What is a SE of caspofungin?
Flushing
358
What is an SE of flucytosine?
Vomiting
359
What AE are associated with griseofulvin?
Induces P450 system
| Teratogenic
360
What drug is commonly used in the oral form to treat fungal nail infections?
Terbinafine
361
What drug is mostly used to treat systemic fungal infections?
Amphotericin B
362
What SEs are associated with amphotericin B?
Nephrotoxicity
Flu like symptoms
Hypokalaemia
Hypomagnesaemia
363
What AEs are associated with azoles?
P450 inhibition
| Liver toxicity
364
What investigation is required before starting a patient on terbinafine?
LFTs (before treatment and 4-6 weeks into treatment)
365
How re streptococci divided?
```
Alpha haemolytic (partial haemolysis)
Beta haemolytic (complete haemolysis)
```
366
What is the most important alpha haemolytic strep?
Strep pneumoniae
Other e.g. is strep viridians
367
How are beta haemolytic streptococci divided?
A-H
A, B and D are the most important ones
368
What is the most important group A beta haemolytic strep?
Strep pyogenes
369
What kinds of infections does strep pyogenes cause?
Erysipelas, impetigo, cellulitis, type 2 necrotizing fasciitis, pharyngitis/tonsillitis
Erythrogenic toxins --> scarlet fever
Can cause rheumatic fever, post-strep GN
370
What a group B beta haemolytic strep?
Strep agalactiae (can cause neonatal meningitis/septicaemia)
371
What are group D beta haemolytic streps?
Enterococcus
372
What is the most common way hepatitis E is spread?
Undercooked pork
373
What is the most common cause of short term hepatitis in the UK?
Hep E
374
What causes leishmaniasis?
Intracellular protozoa leishmania
375
How is leishmania spread?
Sand flies
376
What are the types of leishmaniasis?
Cutaneous leishmaniasis
Mucocutaneous leishmaniasis
Visceral leishmaniasis (kala-azar)
377
What causes cutaneous leishmaniasis?
Leishmania tropica or Leishmania mexicana
378
What are features of cutaneous leishmaniasis?
Crusted lesion at site of bite
| May be underlying ulcer
379
What causes mucocutaneous leishmaniasis?
Leishmania braziliensis
380
What are features of mucocutaneous leishmaniasis?
Skin lesions spread to involve mucosae of nose, pharynx etc.
381
What most commonly causes visceral leishmaniasis?
Leishmania donovani
382
What are features of visceral leishmaniasis?
```
Fever, sweats, rigors
Massive splenomegaly, hepatomegaly
Poor appetite, wt loss
Grey skin (kala-azar = black sickness)
Pancytopenia secondary to hypersplenism
```
383
What is the gold standard for diagnosing visceral leishmaniasis?
Bone marrow/splenic aspirate
384
Do you require consent to test for HIV?
Yes
385
What is red man nsyndrome?
Vancomycin related activation of mast cells with release of histamine due to rapid IV infusion of vancomycin
386
What are typical symptoms of redman syndrome?
Redness
Pruritus
Burning sensation in upper body
Severe cases can cause hypotension + chest pain
387
How is red man syndrome managed?
Cessation of infusion
| After symptoms have resolved, recommence at slower infusion rate
388
What AEs are associated with vancomycin?
Nephrotoxicity
Ototoxicity
Thrombophlebitis
Red man syndrome
389
What is vancomycin used to treat?
Gram positive infections, esp MRSA
390
BV is primarily due to the overgrowth of what bacteria?
Gardnerella vaginalis
| which leads to a fall in lactic acid producing lactobacilli --> pH to increase
391
What kind of virus is mumps?
RNA paramyxovirus
392
How is mumps spread?
By droplet
393
Where does mumps tend to spread?
Respiratory tract epithelial cells --> parotids --> other tissues
394
What are clinical features of mumps?
Fever
Malaise, muscular pain
Parotitis (earache, pain on eating), unilateral initially and then usually becomes bilateral
395
How is mumps managed?
Rest
Paracetamol
Notifiable disease
396
What are complications of mumps?
Orchitis (4-5 days after parotitis)
Hearing loss (usually unilateral and transient)
Meningoencephalitis
Pancreatitis
397
What should all HIV patients with CD4 <200 be given?
Prophylaxis against PJP (co-trimoxazole)
398
If an asymptomatic contact of a chlamydia patient comes in should you still treat?
Yes - treat straight away without waiting for results of test
399
How are animal bites managed?
Cleans wound
Co-amoxiclav
(if penicillin allergic - doxycyline + metronidazole)
400
What organisms commonly infect human bites?
```
Streptococci spp.
Staphylococcus aureus
Eikenella
Fusobacterium
Prevotella
```
401
What antibiotic is recommended for human bites?
Co-amoxiclav
402
What cancers is HPV linked to?
```
Cervical
Anal
Vulval and vaginal
Penile
Mouth and throat
```
403
Apart from boys and girls aged 12-13, who else should be offered the HPV vaccination?
MSM under the age of 45 (due to risk of anal, throat and penile cancers)
404
What kind of bacteria is clostridium botulinum?
Gram positive anaerobic bacillus
405
What toxin does clostridium botulinum produce?
Botulinum toxin (neurotoxin which irreversibly blocks release of ACh)
406
How might someone get botulism?
From eating contaminated foods (e.g. tinned) or IVDA
407
What nerves does the botulinum toxin often affect?
Bulbar muscles and ANS
408
What are features of botulism?
```
No sensory disturbance
Descending flaccid paralysis
Diplopia
Ataxia
Bulbar palsy
```
409
How is botulism managed?
Botulism antitoxin (only effective if given early) + supportive care
410
What are the main two forms of trypanosomiasis?
African trypanosomiasis - sleeping sickness
American trypanosomiasis - Chagas disease
411
How is trypanosomiasis spread?
Tsetse fly
412
What are clinical features of African trypanosomiasis?
Trypanosoma chancre - painless s/c nodule at site of infection
Intermittent fever
Enlargement of posterior cervical LNs
Later => CNS involvement, e.g. somnolence, headaches, mood changes, meningoencephalitis
413
How is early African trypanosomiasis managed?
IV pentamidine or suramin
414
How is late African trypanosomiasis or African trypanosomiasis with CNS involvement managed ?
IV melarsoprol
415
How does acute Chaga's disease present?
Chagoma (an erythematous nodule at site of infection) + periorbital oedema
416
What are features of chronic Chaga's disease?
Myocarditis ==> dilated cardiomyopathy + arrhythmias
| GI features - megaoesophagus + megacolon --> dysphagia and constipation
417
What is the management of Chaga's disease?
Acute phase - azole/nitroderivates (benznidazole)
Chronic - treat complications
418
Should asymptomatic bacteruria in catheterised patients be treated?
NO
419
What is the most frequent and severe manifestation of chronic Chaga's disease?
Cardiomyopathy
420
What is the mode of action of rifampicin?
Inhibits bacterial DNA dependent RNA polymerase preventing transcription of DNA into mRNA
421
What AEs are associated with rifampicin?
Potent CYP450 liver inducer
Hepatitis
Orange secretions
Flu like symptoms
422
What AEs are associated with isoniazid?
Hepatitis
Peripheral neuropathy
Agranulocytosis
423
What AEs are associated with pyrazinamide?
Myalgia
Arthalgia
Hepatitis
Hyperuricaemia
424
Why should nitrofuratoin not be given to pregnant women in the third trimester?
Can cause haemolytic anaemia in newborn
425
What AEs are associated with trimethoprim?
Myelosupression
Transient rise in cr
Hyperkalaemia
(due to tubular dysfunction by blocking the ENaC channel)
426
How quickly do symptoms of norovirus develop after becoming infected?
15-50 hours
427
What are symptoms of norovirus?
Nausea, vomiting, diarrhoea
| Headaches, low grade fevers, myalgia
428
How is norovirus spread?
```
Faecal oral (when virus aerosolized by vomiting/toilet flushing)
Can be transmitted by cross contamination from surfaces
```
429
Once the norovirus enters the body what does it do?
Enters cell via host receptor mediated endocytosis and replicates in small intestine
430
How is transmission of norovirus limited?
Isolation of infected individuals
Hand hygiene with soap and water
Hand gels not effective enough
431
How is norovirus diagnosed?
Hx and stool culture viral PCR
432
What are neurological sequalae of meningitis?
Sensorineural hearing loss (most common)
Epilepsy, paralysis
Sepsis, intracranial abscess
Brain herniation, hydrocephalus
433
What are CIs to LP for meningitis?
```
Any signs of raised ICP -
Focal neurological signs
Papilloedema
Significant bulging of fontanelles
DIC
Signs of cerebral herniation
```
For patients with menigococcal septicaemia an LP is CI - blood cultures and PCR for meningococcus should be obtained
434
How should meningitis in children be managed?
1. Antibiotics
2. IV dexamethasone if >3 months and any of:
a. frankly purulent CSF
b. CSF WCC >1000/microlitre
c. raised CSF WCC with protein conc >1g/l
d. bacteria on gram stain
3. Fluid
4. Cerebral monitoring
5. PH notification and prophylaxis of contacts
435
What are symptoms of meningococcal sepsis/meningitis?
```
Headache
Fever
NV
Photophobia
Drowsiness
Seizures
```
436
What are signs of meningococcal sepsis/meningitis?
Neck stiffness
| Purpuric rash
