Infectious disease 2 Flashcards

Question

what is the hep B vaccine?

Answer 1

contains HBsAg adsorbed onto aluminum hydroide adjuvant and is prepared from yeast cells using recombinant DNA technology

Answer 2

``` over 40 years obesity smoking alcohol excess immunosupression ```

Answer 3

hepatits c is a flavicirus incubation period is 6-9 weeks it is mainly spread via blood ***NO VACCCINE FOR HEP C

Answer 4

a transient rise in serum aminotransferases - jaundice fatigue arthralgia

Answer 5

``` unsafe medical practice IV or intranasal drug use blood transfusion or organ transplant heavy alcohol use HIV ```

Answer 6

hep c virus (HCV) antibody enzyme immunoassay (EIA) hep c virus RNA PCR serum aminotransferases

Answer 7

around 15-45% of patients will clear the virus after acute infection the majorty will develop chronic infection (55-85%) and 20-30% will go on to develop cirrhosis with in 20 years there is and increased risk of hepatocellular carcinoma

Answer 8

the persistence of HEP C RNA in the blood for more that 6 months

Answer 9

``` rheumatological problems: arthralgia, arthritis eye problems - sjogren's syndrome cirrhosis hepatocellular cancer cryoglobulinaemia - typically type II porphyria cutanea tarda membranoproliferative glomerulonephritis ```

Answer 10

recent infection - initiate antiviral therapy chronic infection - treatment should depend on the viral genotype - this should be tested prior to treatment - currently a combination of protease inhibitors (e.g. daclatasvir plus sofosbuvir or sofosbuvir plus simeprevir) with or without ribavirin are used

Answer 11

it is a single stranded RNA virus It is an incomplete RNA virus that requires hepatitis B surface antigen to complete its replication and transmission cycle

Answer 12

co-infection - when hep B and D infection at the same time superinfection - patient has hep B and the subsequently develops hep D infection - superinfection is associated with a high risk of fulminant hepatitis, chronic hepatitis an cirrhosis

Answer 13

HDV IgM and IgG = active infection (IgG is not protective) | HDV RNA PCR

Answer 14

``` IgM = active infection IgG = recovery/protective ```

Answer 15

RNA hepevirus spread by the faecal-oral route incubation period 3-8 weeks common in central and SE asia, north and west africa and in mexico carries significant mortality during pregnancy does not cause a chronic disease and does not increase risk of hepatocellular carcinoma currently no vaccination

Answer 16

``` acute diverticulitis cholecystitis (with secondary infection) ascending cholangitis appendicitis spontaneous bacterial peritonitis intra-abdominal abscess ```

Answer 17

``` anaerobes - bacteroids and clostridium E.coli Klebsiella Enterococcus streptococcus ```

Answer 18

co-amoxiclav - provides good gram positive, negative and anaerobic cover, does not cover pseudomonas or atypical bacteria Quinolones (ciprofloxacin and levofloxacin) - reasonable gram postive and negative and also cover atypical bacteria however the do not cover anaerobes so are usually paired with metronidazole when treating abdo infections Metronidazole - excellent for anaerobic bacteria but does not provide any cover against aerobic bacteria Gentamicin - very good gram negative cover with some gram positive cover particularly against staph. Vancomycin - very good gram positive cover including MRSA - it is often combined with gentamicin to cover gram negative and metronidazole to cover anaerobes cephalosporins - broad spectrum against gram positive and gram negative but not effective against anaerobes - they are often avoided due to the risk of developing c.diff infection Tazocin and meropenem - piperacillin/Tazobactam (tazocin) and meropenem are heavy hitting antibiotics that cover gram positive, gram negative and anaerobic bacteria - usually reserved for patients who are very unwell and are not responding to other antibiotics

Answer 19

patients with liver failure

Answer 20

Plasmodium falciparum Plasmodium vivax Plasmodium ovale Plasmodium malariae

Answer 21

plasmodium falciparum - it is also the most common type of malaria it accounts for 75% of cases

Answer 22

sickle cell trait G6PD deficiency HLA- B53 absence of duffy antigens

Answer 23

p. vivax and p. ovale

Answer 24

when a mosquito bites human the sporozoites are injected into the human by the mosquito they the travel to the liver where they can lie dormant as hypnozoites for several years if they are p.vivax or p. ovale. They mature in the liver into merozoites which enter and infect red blood cells. In red blood cells, the merozoites reproduce over different time periods depending on the species. After they reproduce the red blood cells rupture releasing more merozoites into the blood causing haemolytic anaemia. This is why people with malaria have high fever spikes, every time the blood cells rupture they get spike - may be 48 hours or 72 hours depending on the species.

Answer 25

``` schizonts on a blood film parasitaemia >2% hypoglycaema acidosis temp >39 severe anaemia ```

Answer 26

``` cerebral malaria - seizures and coma acute renal failure - blackwater fever, secondary to intravascular haemolysis acute respiratory distress syndrome hypoglycaemia DIC ```

Answer 27

``` non-specific symptoms - fever, sweats and rigours malaise myalgia headache vomiting ``` signs - pallor due to anaemia - hepatosplenomegaly - jaundice as bilirubin is released during the rupture of RBCs

Answer 28

Giemsa-stained thick and thin blood stains - thick films are more sensitive for detect parasites where as thin films permit species identification and parasitameia - 3 samples should be sent over 3 consecutive days to exclude malaria due to the cycle of malaria being released into the blood from the blood cells ``` rapid diagnostic tests FBC clotting profile U&Es LFTs blood glucose ```

Answer 29

plasmodium vivax

Answer 30

plasmodium malariae

Answer 31

ovale and vivax have a hypnozoite stage where they can stay dormant in the liver for months/years so therefore may relapse following treatment

Answer 32

if sensitive to chloroquine and non pregnant - chloroquine or hydroxychloroquine if chloroquine-resistant - ACTs - artemisinin-based combination therapies (artemether with lumefantrine (riamet))

Answer 33

parenteral antimalarial regimen - artesunate other options include artemether or quinine supportive care and admission to intensive care if parasite count is greater than 10% the exchange transfusion should be considered

Answer 34

either an ACT or chloroquine if pregnant in first trimester and chloroquine resistant then treat with quinine

Answer 35

proguanil and atovaquone (malarone) - taken daily 2 days before, during and 1 week after being in endemic area, most expensive - around £1 per tablet, best side effect profile Mefloquine - taken once weekly 2 weeks before, during and 4 weeks being in enemic area - can cause bad dreams and rarely psychotic disorders and seizures Doxycycline - taken daily 2 days before, during and 4 weeks after being in endemic area - borad spectrum antibiotic so causes side effects like diarrhoea and thrush, also makes patients more sensitive to the sun causing a rash and sunburn.