Infectious Diseases Flashcards
what is the definition of sepsis?
life threatening organ dysfunction caused by a dysregulated host response to infection
what is the definition of septic shock ?
a subset of sepsis with profound circulatory cellualr and metabolic abnormalities, associated with greater risk fo mortality than sepsis alone
what is the sepsis 6?
give O2 give IV ABX Give fluids Measure lactate measure urine output take blood cultures
what are teh most common tropical ifnections seen in lri?
typhoid (enteric) fever, dengue fever, and malaria
what are teh commonest manifestations of travel related illnesses?
- GI symptoms (D+V)
- jaundice
- reticuloendothelial change (lymphadenopathy, hepatosplenomegaly)
- resp symptoms (cough, SOB)
- rash
what important questions in a Hx need to be asked to a perosn with a fever returnign from travel?
- geographic region wihtin last 12 months !!!
- duration and exact dates of travel
- onset and nature of signs and symptoms
- types of accom
- exposures: insects, animals, freshwater lakes, canal warr
- type of food/water consumed
- sexual history,
- PMHx and immunosuppressive therapy?
what is the time frame of different infections? (dengue, viral, malaria, typhoid, HIV, baacterial, TB)
0-10 days: dengue, rickettsia, viral, gastrointestinal (bacteria, amoeba)
10-21 days: malaria, typhoid, primary HIV infection
>21 days: malaria, chronic bacterial infections, TB, parasitic infections
what are some useful pre travel immunisations available?
vaccinations for: - Hep A, hep B - typhoid - tetanus - MMR - yellow fever - rabies or malaria chemoprophylaxis
what are some suggested investigations to do in a patient with fever and returned from travel?
- FBC, LFTs, U+Es, electrolytes
- malaria smears +/- antigen detection dipstick: at least 3 times over 24-48 hrs
- blood cultures x2
- urinalysis (+/- urine uclture)
- stool culture +/- stool for ova, parasites, cysts
- CXR
- HIV, Hep B, Hep C, syphillis serology
- acute serology tube to be saved in lab
how is malaria transmitted?
night biting Anopheles mosquitoes
what are the different types of plasmodium species of malaria?
plasmodium falciparum (90% africa)- most serious adn most common plasmodium vivax (SE asia) plasmodium ovale (SE asia)
what is teh presenation of a patient with malaria
- abrupt onset of rigors
- high fevers
- malaise
- severe headache
- myalgia
- vague abdo pain
- nausea + vomiting
- diarrhoea
- jaundice and hepatosplenomegaly
what are teh blood results like in a patient with malaria ?
anaemic
thrombocytopenic
leukopenic
abnormal liver enzymes
what are teh complications that can occur with p. falciparum malaria when untreated?
- hypoglycaemia
- renal failure
- pulmonary oedema
- neurologic deterioation
- death
what is the treatment for malaria (specifying with plasmodium specied)
P. falciparum - IV artesunate (+quinine and doxycycline for 7 days)
P. vivax and P.ovale - chloroquine (3-4 days) and primaquine (14 days)
where are the most common areas in the world to get typhoid fever?
SE asia
Southern and Central America
what are the signs of symptoms of a patient with typhoid fever?
sustained fever anorexia malaise vague abdo discomfort constipation diarrhoea dry cough
pulse temperature dissociation (low pulse)
heptosplenomegaly
rose spots (30-50% patients)
what are the common blood test results for patients with typhoid fever?
leucopenia
lymphopenia
raised CRP
what investigative results are needed to diagnose typhoid fever?
isolation of organism in cultures of blood (80% if 2 cultures taken) - gram negative rod of salmonella typhi stool urine bone marrow duodenal aspirates
what is the treatment for typhoid fever?
- IV ceftriaxone 2g OD
- switch to PO ciprofloxacin 500mg BD or PO azithromycin 500mg OD once sensitivities known
what is enteric fever?
overarching name including typhoid fever
it encapsulates the bacterial infections caused by salmonell atyphi and salmonella paratyphi