Microbiology 24 - Fever in the Returning Traveller + PUO

Question 1

Recall some differentials for fever and rash in the returning traveller

Answer 1

Viral: dengue, chickungunya, measles
Bacterial: typhoid (look for rose spots)

Question 2

Recall some differentials for fever and abdo pain in the returning traveller

Answer 2

Typhoid fever
Amoebic liver abscess

Question 3

Recall some differentials for fever and cytopaenias in the returning traveller

Answer 3

Dengue, chickungunya, typhoid (anaemia), malaria

**the mosquito ones + typhoid

Question 4

Recall some differentials for fever and haemorrhage in the returning traveller

Answer 4

Viral haemorrhagic fevers (dengue/ ebola)
Meningococcaemia

Question 5

Recall a differential for fever and eosinophilia in the returning traveller

Answer 5

Schistosomiasis

Question 6

Recall some differentials for fever > 6 weeks post-travel in the returning traveller

Answer 6

Vivax malaria
Acute hepatitis
TB
Amoebic liver abscess

Question 7

What % of parasitaemia constitutes a severe malaria?

Answer 7

>2%

Question 8

What type of mosquito carries malaria?

Answer 8

Female Anopheles

Question 9

Recall the different types of malaria

Answer 9

Falciparum
Vivax
Ovale
Malariae
Knowelsi

Question 10

What acid base abnormality may be seen in malaria?

Answer 10

Metabolic acidosis

Question 11

Why is malaria sometimes known as ‘blackwater fever’?

Answer 11

Due to the haemaglobinuria

Question 12

What is the gold standard test for malaria?

Answer 12

Thick and thin blood films

Question 13

What type of mosquito is a vector for dengue virus?

Answer 13

Aedes

Question 14

What are the symptoms of dengue?

Answer 14

Fever
Headache
Myalgia
BLANCHING RASH - this spares the hands and feet (unlike chickengunya)

Question 15

What cytopaenias are expected in dengue infection?

Answer 15

Thrombocytopaenia
Neutropaenia

Question 16

What are the possible causative organisms in typhoid (enteric) fever?

Answer 16

Salmonella typhi/ paratyphi

Question 17

What is the phrase “himalaya peak fevers” pathognemonic for?

Answer 17

Typhoid fever

Question 18

What is the treatment of typhoid fever?

Answer 18

Ceftriaxone then azithromycin

Question 19

What is the definition of pyrexia of unknown origin?

Answer 19

>38.3 degrees on several occaisons persisiting >3/52 without diagnsois depsite 1/52 of intensive investigations

Question 20

What are the 3 types of PUO?

Answer 20

1. classical
2. healthcare associated
3. neurtopaenic PUO
4. HIV associated PUO

Question 21

What can cause PUO?

Answer 21

Question 22

What are some common causes of fever in a returning traveller?

Answer 22

Causes: tropical diseases (especially malaria, typhoid, dengue, viral haemorrhagic fevers), bacterial diarrhoea (E. coli, cholera) - Don’t forget about common UK causes too, e.g. UTI, pneumonia, influenza - Beware of questions pointing you towards STIs (e.g. HIV seroconversion)

Question 23

What causes typhoid?

Answer 23

salmonella typhi or parathyphi

anaerobic gram -ve bacilli

Question 24

symptoms of typhoid fever

Answer 24

Travel to India, transmitted in food and water, incubation 1-2wks
• Causes enteric fever by infecting Peyers patches in intestines
o Fever, headache, constipation (not diarrhoea!) o Rose spots, relative bradycardia, hepatosplenomegaly

Question 25

treatment of typhoid fever

Answer 25

IV ceftriaxone --\> PO azithromycin need to vaccinate them as well \*\*need to treat them as it can cause GI perforation\*\*

Question 27

What type of virus is dengue virus? what transmits it?

Answer 27

flavivirus transmitted by ades mosquito

Question 28

Where is dengue commonly spread from?

Answer 28

South-East Asia, urban environments, short incubation (days) \*\*think vietnam\*\*

Question 29

symptoms of dengue

Answer 29

myalgia, fever, rash. Reasonably mild + self-limiting \*\*not as bad as malaria (but bad if you get infected again with a different serotype\*\*

Question 30

what causes dengue haemorrhagic fever?

Answer 30

if you get re-infected with a different serotype \*\*rare in travellers - as uncommon to be re-infected needs supportive management

Question 31

what type of infection is malaria?

Answer 31

protozoal infection (Plasmodium spp.) spread by female anopheles mosquito- bites at night, attracted by heat + CO Areas of the world: Asia/africa/south america

Question 32

classification of malaria

Answer 32

falciparum and non-falciparum \*\*falciparum - most common and most severe \*\*non-falciparum: P. vivax, p ovale, p malariae, p knowlesi

Question 33

Treatment of non-falciparum malaria

Answer 33

Chloroquine then primaquine (c then p) primaquine prevents relapse of symptoms as non falciparum malaria has a hypnoxzoite stage

Question 34

Pattern of fever in non-falciparum malaria

Answer 34

All 48 hour (tertian fever) except for P. malariae - 72h fever

Question 35

What do you see on blood film in non-flaciparum malaria?

Answer 35

schuffner's dots

Question 36

What pattern of fever do you get in falciparum malaria?

Answer 36

tertian fever (48 hourly)

Question 37

investigations for falciparum malaria

Answer 37

thick and thin blood films - x 3 thick- shows malaria thin - shows the species

Question 38

treatment of falciparum malaria

Answer 38

**Mild:** artemesin combination therapy (Riamet – artemether + lumefantrine) § **Severe:** IV artesunate

Question 39

Features of severe falciparum malaria

Answer 39

Question 40

What infections are spread through mice?

Answer 40

``` Hantan viruses(fleas), Lyme borreliosis, Ehrlichia, Bartonella Lymphocytic choriomeningitis ```

Question 41

What infections are spread by rats?

Answer 41

``` Rabies, Leptospirosis, Lassa fever, Hantan viruses, Plague, Pasteruellosis, Haverhill fever (Rat-bite) ```

Question 42

what diseases can be spread by cats?

Answer 42

Bartonellosis (cat scratch), Leptospirosis, Q-Fever, Toxoplasmosis, Rabies, Ringworm, Toxocariasis

Question 43

what diseases are spread by dogs?

Answer 43

Hydatid disease, Leptospirosis, Brucellosis, Q-Fever, Rabies, (MRSA!!), Ringworm, Toxocariasis

Question 44

what diseases are spread by small ruminants

Answer 44

Anthrax, Leptospirosis, Brucella, Bovine TB, Anaplasmosis, Toxoplasmosis, E. coli 0157, Rift Valley fever, Ringworm

Question 45

what diseases are spread by swine?

Answer 45

Brucellosis, Leptospirosis, Erysipeloid, Cysticercosis, Trichinella, HEV, Influ A!, Swine Streptococcal sepsis

Question 46

what diseases are spread by birds?

Answer 46

Psitticosis, Influenza, Cryptococcus, Influ A!!!, Poultry- salmonella, West- Nile fever

Question 47

what diseases are associated with water sports?

Answer 47

Leptospirosis, HAV, Giardia, Toxoplasmosis, Mycobacterium marinum/ulcerans, Burkholderia pseudomallei, E. coli

Question 48

what diseases are water borne?

Answer 48

Campylobacter, Salmonella, VTEC O157, Cryptosporidium

Question 49

what diseases are food-associated?

Answer 49

Listeria (cow cheese-human), Taenia, Cysticercosis, toxoplasmosis, trichinellosis, Food-associated yersiniosis, Giardia

Question 50

What type of bacteria is brucella?

Answer 50

gram negative aerobic bacillus \*\*BRUtal - negative \*\*b for bacillus

Question 51

How is brucellosis transmitted?

Answer 51

contaminated food (untreated milk / dairy products), direct animal contact (cows, goats, sheep, pigs)

Question 52

presentation of brucellosis

Answer 52

``` undulant fever (peaks in evening), myalgia, arthritis, spinal tenderness, hepatosplenomegaly, epididymo-orchitis ``` MAIN THING- UNDULANT FEVER **(think brucella--\>cow--\>udder--\>UNdulant fever)**

Question 53

diagnosis of brucellosis

Answer 53

Serology - anti-O-polysaccharide antibody. WCC usually normal / neutropenia

Question 54

treatment of brucellosis

Answer 54

4-6wks doxycycline + streptomycin

Question 55

what type of virus is rabies? most common vectors?

Answer 55

rhabdovirus most common vectors: dogs and bats

Question 56

presentation of rabies

Answer 56

Prodrome – fever, headache, sore throat b. Acute encephalitis (hyperactive state) c. Migration to CNS (after months – yrs) à fatal encephalitis, **hypersalivation**, **hydrophobia**

Question 57

what are negri bodies indicative of?

Answer 57

rabies

Question 58

treatment of rabies

Answer 58

IgG post exposure before the development of symptoms

Question 59

what causes plague? what type of bacteria ?

Answer 59

yersinia pestis ## Footnote **gram negative lactose fermenter**

Question 60

presentation of plague

Answer 60

Bubonic plague – flea bites human – Swollen LN (Bubo) – dry gangrene Pneumonic plague – Usually seen during epidemics, person-person spread

Question 61

treatment of plague

Answer 61

Streptomycin, Doxycycline, Gentamicin, Chloramphenicol (in meningitis)

Question 62

what bacteria causes leptospirosis?

Answer 62

L. interrogans

Question 63

what type of bacteria is L. interrogans?

Answer 63

gram negative obligate aerobic motile **spirochaete**

Question 64

presentation of leptospirosis

Answer 64

high fever, **conjunctival haemorrhages**, jaundice, meningism, renal failure, haemolytic anaemia buzzword: swimming in tropical waters

Question 65

treatment of leptospirosis?

Answer 65

amoxicillin, erythromycin, doxycycline or ampicillin

Question 66

what causes anthrax?

Answer 66

bacillus anthracis

Question 67

how does anthrax present?

Answer 67

cutaneous: painless round black lesions + rim of oedema pulmonary: massive lymphadenopathy + mediastinal haemorrhage \*\*skin + lungs \*\*

Question 68

treatment of anthrax

Answer 68

doxycycline/ciprofloxacin

Question 69

what causes lyme disease?

Answer 69

borrelia burgdoferi

Question 70

what type of bacteria is borrelia bugdoferi?

Answer 70

spirochaete

Question 71

what transmits lyme disease?

Answer 71

arthropods - ixodes i.e. ticks eg on deer during hike

Question 72

presentation of lyme disease

Answer 72

**Early:** erythema chronicum migrans (bullseye rash), flu-like **Late persistent:** focal neurology, neuropsychiatric, arthritis

Question 73

treatment of lyme disease

Answer 73

Rx: Doxycycline 2-3wks, (also amoxicillin, cephalosporins) o If CNS issues, IV ceftriaxone 2-4wks

Question 74

what causes q fever?

Answer 74

coxiella burnetti

Question 75

how is q fever transmitted?

Answer 75

via cattle/sheep

Question 76

how does q fever present?

Answer 76

atypical pneumonia- dry cough, fever, no rash

Question 77

treatment of q fever

Answer 77

doxycycline

Question 78

what causes leishmania?

Answer 78

protozoa L. major or L. tropica

Question 79

what are the types of leishmania?

Answer 79

1. cutaneous 2. diffuse cutaneous 3. muco-cutaneous 4. visceral = kala azar

Question 80

What causes cutaneous leishamniasis? presentation?

Answer 80

L. major or L. tropica **Transmission:** sandfly bite (South America, Middle East) **o Presentation:** Skin ulcer at site of bite --\> multiply in dermal macrophages --\>heals after 1yr leaving depigmented scar § May be single or multiple painless nodules which grow + **ulcerate** **\*\*key feature is ulceration\*\***

Question 81

what causes diffuse cutaneous lieshamnia and how does it present?

Answer 81

Pts with immunodeficiency --\> nodular skin lesions but do NOT ulcerate

Question 82

Muco-cutaneous leishamanisasis

Answer 82

Muco-cutaneous, eg: L. braziliensis o Dermal ulcer (same as cutaneous leishmaniasis) o Months to yrs later à ulcers in mucous membranes of nose and mouth

Question 83

visceral leishamanisis?

Answer 83

Usually young malnourished child o Abdo discomfort and distension, anorexia, weight loss o Leishmania donovani: invasion of reticuloendothelial system à hepato-splenomegaly, BM invasion. Later, disfiguring dermal disease (PKDL)

Question 84

Trypanosomiasis?

Answer 84

Transmitted by Tsetse fly Causes sleeping disease

Question 85

most common cause of fever in returning traveller?

Answer 85

malaria

Question 86

what is torniquet test used for?

Answer 86

dengue fever

Question 88

gram negatvie rod spread via unpasteurised dairy

Answer 88

brucellosis

Question 89

presentation of schistosomiasis

Answer 89

**Acute infections** Acute symptoms typically only develop in people who travel to endemic areas, as they don't have any immunity to the worms. Acute manifestations may include: - swimmers' itch - acute schistosomiasis syndrome **(Katayama fever)** fever urticaria/angioedema arthralgia/myalgia cough diarrhoea **eosinophilia** **Chronic infections** Schistosoma haematobium These worms deposit egg clusters (pseudopapillomas) in the **bladder**, causing inflammation. The calcification seen on x-ray is actually calcification of the egg clusters, not the bladder itself. Depending on the site of these pseudopapillomas in the bladder, they can cause an obstructive uropathy and kidney damage. This typically presents as a 'swimmer's itch' in patients who have recently returned from Africa. **Schistosoma haematobium is a risk factor for squamous cell bladder cancer.** Features frequency haematuria bladder calcification Investigation for asymptomatic patients serum schistosome antibodies are generally preferred **for symptomatic patients the gold standard for diagnosis is urine or stool microscopy looking for eggs** Management single oral dose of **praziquantel** _Schistosoma mansoni and Schistosoma japonicum_ These worms mature in the liver and then travel through the portal system to inhabit the distal colon. Their presence in the portal system can lead to progressive hepatomegaly and splenomegaly due to portal vein congestion. These species can also lead to complications of liver cirrhosis, variceal disease and cor pulmonale. _Schistosoma intercalatum and Schistosoma mekongi_ These are less prevalent than the other three forms, but are both attributed to intestinal schistosomiasis.

Question 90

describe the presentation of toxoplasmosis

Answer 90

**immunocompteet** Most infections are asymptomatic. Symptomatic patients usually have a self-limiting infection, often having clinical features resembling infectious mononucleosis (fever, malaise, lymphadenopathy). Other less common manifestations include meningoencephalitis and myocarditis. Serology is the investigation of choice. No treatment is usually required unless the patient has a severe infection or is immunosuppressed. **HIV/immunosuppressed patients** Cerebral toxoplasmosis accounts for around 50% of cerebral lesions in patients with HIV constitutional symptoms, headache, confusion, drowsiness CT: usually _single or multiple ring-enhancing lesion_s, mass effect may be seen management: pyrimethamine plus sulphadiazine for at least 6 weeks Immunosuppressed patients may also develop a chorioretinitis secondary to toxoplasmosis.