Infectious disease Flashcards
1
Q
TB meningitis CSF features
A
Cloudy
Lymphocytosis
Low glucose
High protein
2
Q
TB meningitis treatment
A
IV rifampicn, isoniazid, pyrazinamide, dexamethasone
Avoid ethambutol due to optic complications
3
Q
Rickettsial disease general features
A
Eschar, vasculitic rash, malaise, lymphadenopathy
4
Q
Types of rickettsial disease
A
Americas - rocky mountain spotted fever
East asia - scrub typhus
5
Q
Complications of rickettsial disease
A
Jaundice, meningoencephalitis, myocarditis, pneumonia and renal failure
6
Q
Treatment of rickettsial disease
A
1) doxycycline
2) azithromycin
7
Q
Fever frequency plasmodium vivax/ovale
A
48 hours
8
Q
Fever frequency plasmodium malariae
A
72 hours
9
Q
Fever frequency plasmodium falciparum
A
24 hours
10
Q
Features of severe falciparum malaria (requires IV artesunate)
A
schizonts on a blood film parasitaemia > 2% hypoglycaemia acidosis temperature > 39 °C severe anaemia complications: cerebral malaria: seizures, coma; acute renal failure: blackwater fever, secondary to intravascular haemolysis, mechanism unknown; acute respiratory distress syndrome (ARDS); hypoglycaemia; disseminated intravascular coagulation (DIC)
11
Q
Treatment of non-severe falciparum malaria
A
artemisin-based combination therapies
e.g. artemethur + lumefantrine / artesunate + amodiaquine
12
Q
1) Treatment of plasmodium vivax / ovale
2) why?
A
1) chloroquine / ACT (if chloroquine resistant area) + primaquine
2) primaquine for hyponozoite stage in liver - risk of relapse if not treated
13
Q
Treatment of malaria in pregnancy
A
chloroquine
14
Q
Treatment options in legionella pneumonia
A
1) macrolides e.g. clarithromycin, erythromycin, azithromycin
2) fluoroquinolones e.g. ciprofloxacin, levofloxacin
15
Q
Pregnant woman with no rash but exposed to chickenpox
A
1) check VZV serology
2) if no immunity, VZV Ig - effective 10 days PEP
16
Q
Pregnant woman with chickenpox
A
1) PO aciclovir
2) IV aciclovir & foetal medicine if severe infection
17
Q
Bone and joint TB mx
A
Initial: RIPE 2 months
Continuing: RI 4 months
18
Q
Mycobacterium avium Mx
A
Rifampicin, ethambutol, clarithromycin - continue until sputum -ve for 12 months
19
Q
Leprosy mx
A
Rifampicin, clofazimine, dapsone 6-12 months
20
Q
Staph aureus bacteraemia mx
A
2 weeks IV fluclox
21
Q
CPE treatment
A
Polymyxins (e.g. colistin), tigecycline, fosfomycin or aminoglycosides (e.g. gent)
22
Q
Yersinia pestis
A
- buboes most common
- pneumonia (person-person - active in madagascar)
- septicaemia
Ix: blood cultre, serology
Mx: IV gent OR doxycycline
23
Q
CMV colitis in HIV CD4 count
A
<50
24
Q
African sleeping sickness parasites
A
West Africa - trypanosoma gambiense
East Africa - trypanosoma rhodesiense
25
African sleeping sickness mx
early: IV pentamidine
| late (CNS): IV melarsoprol, suramin, eflornithine, nifurtimox
26
Chagas disease features
early: asymptomatic or chagoma
complications: myocarditis / dilated cardiomyopathy, megaoesophagus or megacolon
27
Chagas disease treatment
azoles e.g. benznidazole
| heart failure management
28
Yellow fever features
- viral haemorrhagic fever
- aedes mosquito
- flu like illness
- period of brief remission
- jaundice, haematemesis, renal failure, thrombocytopenia
- hepatic inclusion bodies (councilman)
29
Strongyloides mx
Ivermectin OR bendazoles
30
Pinworm (pruritis ani, eggs on tape)
Bendazoles
31
Loa loa (loiasis)
- nematode cause of filiariasis
- Features: soft tissue swelling, eye worm, numbness in affected limb
- Mx: diethylcarbamazine
32
River blindness
- Onchocera volvulus
- hyperpigmentation
- blindness
- mx: ivermectin
33
Roundworm elephantitis
Wuchereria bancrofti from mosquito
| Mx: diethylcarbamazine
34
Schistosomiasis types
- Intestinal -> pulmonary hypertension / liver cirrhosis: mansoni / intercalatum
- urinary: haematobium - risk squamous cell carcinoma and bladder neck fibrosis
35
Schistosomiasis mx
Praziquantel
| + steroids if acute disease -> prevents type 3 hypersensitivity reaction
36
ESBL
Carbapenems e.g. meropenem
| OR nitrofurantoin / fosfomycin
37
Diet after giardiasis
Avoid lactose 2-6 weeks
38
mycobacterium marinum
- fish exposure
- break in skin -> cutaneous lesions
- lymphatic spread
- doxy / cipro / clari
39
Rabies mx already immunised
2x further vaccine doses
40
Rabies mx no immunisation
1) touching only - nil
2) no bleeding - full immunisation
3) transdermal bite / lick broken skin - rabies Ig & full immunisation
41
Typhoid Mx
1) Cefotaxime / ceftriaxone
2) Ciprofloxacin in certain sensitive cases
3) Azithromycin
42
CMV / HHV5 treatment
IV ganciclovir
43
Mycobacterium avium features
- fever, malaise, weight loss
- pulmonary symptoms
- abdominal: diarrhoea, abdo pain, deranged LFTs, hepatosplenomegaly
44
Mycobacterium avium treatment
Rifampicin/rifabutin + clarithromycin + ethambutol
| - until 12 months -ve sputum
45
Complications of schistosomiasis
- Haematobium: urinary tract fibrosis +/- hydronephrosis, squamous cell carcinoma of the bladder
- portal hypertension and cirrhosis
- pulmonary hypertension
46
Cutaneous larva migrans features
Dog / cat hookworm
Passes in their faeces -> contact with human skin
Hypersensitivity reaction in the skin but cannot get passed basement membrane or replicate - no systemic disease
47
Cutaneous larva magrans mx
Ivermectin
OR
albendazole
48
Effect of P450 inhibition on steroid treatment
Possible iatrogenic cushing's
49
HLA B 5701 allele positive in HIV?
Avoid abacavir (fatal hypersensitivity)
50
Hep B post exposure prophylaxis
No vaccine / non-responders: hep B Ig + vaccination
Known responders: hep B vaccine 2 x booster
Incomplete vaccine: hep B Ig + accelerated course
51
Hep C post exposure prophylaxis
NONE! 6 monthly hep C PCR +/- treatment
| usually sofosbuvir combinations +/- ribavarin
52
HIV post exposure prophylaxis
- If undetectable viral load --- very low risk, re test HIV at 8-12 weeks
- If high risk, offer combination ART e.g. tenofovir, emtricitabine, lopinavir and ritonavir for 4 weeks --- re-test at 12 weeks
53
Cryptococcal meningitis features
```
Low CD4 count
meningitic features
sub acute
raised ICP with false localising signs
seizures
CT: nil or meningeal enhancement
CSF: pleocytosis, high protein, low glucose, india ink +ve
```
54
Cryptococcal meningitis mx
Amphotericin + fluconazole / flucytosine
55
TB mx in HIV on protease inhibitors
Rifabutin, isoniazid, pyrazinamide, ethambutol
| rifampicin increases ART protease inhibitor metabolism
56
Leishmaniasis pathogenesis
Intracellular protozoan (leishmania) transmitted by sand flies can cause visceral, cutatneous and mucocutaneous patterns of disease
57
Cutaneous leishmaniasis features
- Leishmania tropica or Leishmania mexicana
| - Crusted lesion at bite site -> ulceration
58
Cutaneous leishmaniasis mx
May self-resolve
Cryotherapy
Topical paromycin
PO ketoconazole
59
Mucocutaneous leishmaniasis features
- Leishmania braziliensis
- initial crusted skin lesions -> mucosa of nose, pharynx
- can occur years to decades after initial infection
60
Mucocutaneous leishmaniasis mx
- Amphotericin B
| - Miltefosine
61
Visceral leishmaniasis features
- Leishmania donovani
- Mediterranean, Asia, South America, Africa
- initial crusted lesion at bite site
- general: fever, sweats, rigors, poor appetite, weight loss
- abdo: massive splenomegaly, hepatomegaly
- haem: pancytopenia secondary to hypersplenism
- grey skin 'kala-azar'
62
Visceral leishmaniasis ix
DAT +ve
Bone marrow / splenic biopsy = gold standard
Can biopsy LNs
63
Visceral leishmaniasis mx
Amphotericin B / sodium stibogluconate / fluclonazole
64
Pneumocystis pneumonia prophylaxis
Reduced dose co-trimoxazole (septrin)
OR
Dapsone
65
VZV treatment in adults
1) immunocompromised
- IV aciclovir if they develop chickenpox
- IVIG if VZV IgG -ve and exposed to chicken pox
2) presenting with complications e.g. pneumonitis, encephalitis - IV aciclovir
66
Shingles
- Immunocompetent
< 72 hours - PO aciclovir
> 72 hours - nil if well
IV acyclovir if Ramsay Hunt / Herpes zoster opthalmicus if severe infection
- Immunocompromised
PO aciclovir if well
IV acyclovir if disseminated / Ramsay Hunt / Herpes zoster opthalmicus
67
Toxoplasma gondii mx
pyrimethamine + sulfadiazine
68
West Nile virus
- similar to japanese encephalitis virus
- single stranded rna flavivirus
- mosquito vector
- most people asymptomatic
- others can have fever +/- maculopapular rash
- some can have CNS: meningitis, encephalitis, acute flaccid paralysis (assymetric, w/i 48 hours), axonal polyneuropathy
69
Tests for syphillis
VDRL & RPR
- false negatives e.g. HIV
- becomes negative after treatment
Antibody tests e.g. treponema pallidum haemagluttination assay
- more specific
- remains positive after treatment
70
Quickest active TB diagnostic test
nucleic acid amplification
71
Dengue fever
- aedes mosquito
- fever
- headache
- myalgia
- pleuritic pain
- petechial rash
- thrombocytopenia
- raised ALT
- may cause DIC -> viral haemorrhagic fever
72
Chikingunya
- ades mosquito
- high fever
- severe joint pain +/- joint pain
- flu-like illness
- transaminitis
- similar to dengue but ++ JOINT PAIN
73
Brucellosis
- brucella bacteria
- un-pasteurised milk
- fever, malaise
- sacroilitis, peripheral joint pain
- hyperhydrosis
- chronic: skin rash, hepatosplenomegaly
- Ix: serology, rose bengal plate test
- Mx: doxycycline + rifampicin
74
Q fever
- coxiella burnetii
- source: abattoir, cattle/sheep
- fever and malaise prodrome
- > PUO, atypical pneumonia, endocartidits (culture -ve)
- mx: doxycyline
75
Tetanus infection mx
- tetanus IVIG
- IV metronidazole
- wound debridement
76
Trypanosomiasis ix
- acute phase: peripheral blood smear
CNS features?
- CTH / MRI -> may show oedema / white matter enhancement late in disease
- LP: microscopy, elevated wcc, elevated IgM, elevated protein
American trypanosomiasis: serology
77
Babesiosis
- tick-borne protozoan infection
- fever, chills, rigors
- haemolytic anaemia
- haemoglobinuria
- reactive hypergammaglobulinaemia
- North east USA endemic
- less headache vs malaria, but otherwise similar
- ix: blood smear, PCR, serology
- mx: azithromycin + atovaquone; exchange transfusion if severe haemolytic anaemia
78
Typhoid features
- salmonella typhii
- fever, malaise, headache, arthrlagia
- abdo pain and CONSTIPATION
- deranged LFTs, hepatosplenomegaly
- relative bradycardia
- rose spots
- leukopenia
- complications: osteomyelitis, GI bleed, myo/endocarditis, meningitis, cholecystitis
79
Filiariasis
- parasitic worm with mosquito as vector
e. g. wuchereria bancrofti
- common in rice paddy fields
- enter lymphatics -> lymphoedema, painful lymphadenopathy
- hypersensitivity reaction in the lungs -> tropical pulmonary eosinophilia - nocturnal wheeze, pulmonary oedema
- general: malaise, intermittent fevers
- Mx
1) diethylcarbamazine
2) ivermectin (esp if high parasitic load)
80
Cysticercosis
- larval stage of taenia solium (pork tapeworm)
- neurocysticercosis -> seizures, headache, vomiting
- extraneural SC nodules
Ix
- CT: cystic lesions
- fundoscopic visualisation of parasites
- serology
- LP is not necessary
Mx
- anticonvulsants
- antiparasitic: albendazole + praziquantel
- + dexamethasone to reduce inflammation with degenerating cyst
81
MRSA pneumonia mx
Linezolid > vancomycin
82
Chlamydia infection
Ix: NAAT of urine and swab
Mx: 7 day doxy or single dose azithromycin
83
Gonorrhoea infection
- urethral swab NAAT
| - IM ceftriaxone (specific to gonorrhoea) + azithromycin (chlamydia cover)
84
Severe malaria features
- GCS <11
- acidosis
- lactate >5
- hypoglycaemia
- parasitaemia >10%
- shock
- GI bleeding
- pulmonary oedema
- jaundice
- creat >265
- severe anaemia
85
Malaria prophylaxis
```
- chloroquine
OR atovaquone + proguanil
OR mefloquine
OR doxycycline
- take until 7 days after return
- most resistance with falciparum
```
86
Cat scratch disease
- bartonella henselae (G-ve rod)
- fever, regional lymphadenopathy, malaise, headache
- preceding papular lesion
Complications
- neuroretinitis - visual loss
- abdo pain / hepatosplenomegaly
- encephalopathy / transverse myelitis
- MSK
Ix:
- serology
- MCS
- LN biopsy
- PCR
Mx: azithromycin
87
When to give steroids in addition to co-trimoxazole for PCP pneumonia
PaO2 <9.3
88
Leptospirosis
- leptospira interogans
- sewage workers, farmers, vets (must come into contact with rat urine)
- fever, flu-like, headache
- renal failure 50%
- jaundice w/ RUQ tenderness but NO hepatosplenomegaly
- meningitis may occur
Mx: benzylpenicillin / doxycycline / cephalopsorins
89
Parvovirus B19 related red cell aplasia: association, blood film, mx
- associated with HIV
- anaemia without reticulocytes
Mx: IVIG
90
Mx of meningiococcal meningitis if severe penicillin allergy
Chloramphenicol
91
Mx of S Aureus endocarditis if penicillin allergic
Vancomycin + rifampicin
92
Vaccines to avoid in HIV+ve patients
```
Live attenuated
- BCG
- intranasal influenza
- typhoid
- oral polio
- cholera
(- yellow fever -> consider if CD4 >200)
(- varicella -> consider if CD4 >200)
(- MMR -> consider if CD4 >200)
```
Decreased efficacy
- hep a/b combo
- hep a / typhoid combo
93
BD glucan
Found in fungi including p. jiroveci
94
Galactomannan
Found in aspergillus
