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Phase 2a Medicine - Riona > Miscellaneous > Flashcards

Flashcards in Miscellaneous Deck (97)
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1
Q

What does HIV stand for?

A

Human immunodeficiency virus

2
Q

What is responsible for most human infections of HIV?

A

HIV1

3
Q

Give 2 groups with the most prevalence for HIV in the UK

A
  • ) Men who have sex with men

- ) IVDUs

4
Q

What does IVDU stand for?

A

Intravenous drug user

5
Q

Give the 7 steps of HIV pathogenesis

A

1) HIV binds to CD4 receptors
2) CD4 positive cells migrate where virus replicates and releases new virions
3) Infection progresses and decreases immunity
4) DNA copy of virus RNA genome made
5) Integrated into host DNA
6) Core viral proteins
7) Completed virus is released

6
Q

What is the viral load of HIV?

A

Number of circulating viruses

7
Q

What does the viral load of HIV predict?

A

Progression to AIDs

8
Q

What does HIV bind via? (Step 1)

A

GP120 envelope protein

9
Q

Where are the CD4 receptors that are bound to HIV? (Step 1)

A

Helper T cells, monocytes, macrophages, neural cells

10
Q

Where do CD4 positive cells migrate to? (Step 2)

A

Lymphoid tissue

11
Q

What do new virions do? (Step 2)

A

Infect new cells

12
Q

Why does immunity decrease as infection progresses in HIV? (Step 3)

A

Depletion and impaired function of CD4 cells

13
Q

What makes a DNA copy of the virus RNA genome? (Step 4)

A

Viral reverse transcriptase enzyme

14
Q

What integrates the DNA copy of the virus RNA genome into host DNA? (Step 5)

A

Integrase

15
Q

What are the core viral proteins initially synthesised as?

A

Large polypeptides that are cleaved by protease

16
Q

What are the 3 stages of HIV?

A
  • ) Seroconversion (primary infection)
  • ) Asymptomatic period
  • ) AIDs related complex
17
Q

What may seroconversion by accompanied by?

A

Transient illness 2-6 weeks after exposure

18
Q

What are the symptoms of seroconversion?

A
  • ) Fever
  • ) Malaise
  • ) Myalgia
  • ) Pharyngitis
  • ) Maculopapular rash
19
Q

What can occur instead of the asymptomatic period of HIV?

A

Persistent generalised lymphadenopathy

20
Q

Give 3 later constitutional symptoms of HIV

A
  • ) Night sweats
  • ) Fever
  • ) Diarrhoea
  • ) Weight loss
  • ) Possible opportunistic infections
21
Q

Give 2 opportunistic infections of HIV

A
  • ) Oral candida
  • ) Herpes zoster
  • ) Herpes simplex
22
Q

What is the precursor to AIDS?

A

AIDS related complex

23
Q

What is AIDS defined as?

A
  • ) HIV plus an indicator disease

- ) CD4 usually <200x10^6

24
Q

How long is the progression from HIV to AIDs usually?

A

8 years

25
Q

How long is the progression from AIDS related complex to AIDS usually?

A

2 years

26
Q

How long is the progression from AIDS to death without treatment?

A

2 years

27
Q

Give 3 indications that HIV progression is more severe

A
  • ) Fever
  • ) Lymphadenopathy
  • ) Cough
  • ) Diarrhoea
  • ) Oral thrush
  • ) Weight loss
  • ) TB
  • ) Herpes zoster (shingles)
28
Q

Which 2 HIV subtypes predominate in the UK?

A

A and B

29
Q

What do we detect in tests for HIV?

A

Serum HIB antibody by ELISA

30
Q

What do we do if the HIV test is negative? (3)

A
  • ) Check again later
  • ) Look for HIV RNA by PCR
  • ) Look for core p24 antigen in plasma
31
Q

What does ELISA stand for?

A

Enzyme linked immunosorbent assay

32
Q

Give 3 ways to prevent HIV

A
  • ) Good education
  • ) Accessible tests and counselling
  • ) Condoms
  • ) Fewer sexual partners and only one at a time
  • ) Decrease alcohol (risky behaviour)
  • ) Circumcision
33
Q

Give 3 complications/opportunistic infections of HIV

A
  • ) TB
  • ) Pneumocystis jiroveci pneumonia
  • ) Candidiasis
  • ) Toxoplasmosis
  • ) Cryptococcal meningitis
  • ) Cytomegalovirus retinitis
  • ) Kaposi’s sarcoma
  • ) Leishmaniasis
34
Q

What 4 tests do we do routinely during treatment of HIV?

A
  • ) CD4 T cell count
  • ) HIV RNA
  • ) Serum U&E, Cl, creatinine, bilirubin, LFT, FBC
  • ) Lipid profile and glucose
35
Q

When should we initiate therapy in HIV?

A
  • ) AIDS defining illness
  • ) CD4 <350
  • ) Pregnancy
  • ) Nephropathy
  • ) HBV
36
Q

What does highly active antiretroviral therapy aim to do?

A

Suppress plasma HIV RNA levels below limit of detection and restore immune function

37
Q

Give 3 types of drug we give in HIV

A
  • ) Nucleoside reverse transcriptase inhibitors
  • ) Protease inhibitors
  • ) Non-nucleoside reverse transcriptase inhibitors
  • ) Integrase strand transfer inhibitors
38
Q

Why do we use >3 drug combinations in HIV treatment?

A

To minimise replication and cross resistance

39
Q

Give an example of a nucleoside reverse transcriptase inhibitor

A
  • ) Tenofovir
  • ) Lamivudine
  • ) Abacavir
40
Q

Give an example of a protease inhibitor

A

Lopanavir

41
Q

Give an example of a non-nucleoside reverse transcriptase inhibitor

A
  • ) Nevirapine

- ) Efavirenz

42
Q

Give an example of an integrate strand transfer inhibitor

A

-) Ellvitegravir

43
Q

What is the most severe type of malaria?

A

P. falciparum

44
Q

Give the 4 main types of malaria

A
  • ) P. falciparum
  • ) P. ovale
  • ) P. vivax
  • ) P. malariae
45
Q

How is malaria transmitted?

A

Plasmodium protozoa injected by bite of female anopheles mosquito

46
Q

Give the 8 pathogenic steps of malaria transmission

A

1) Female mosquito takes blood meal containing gametocytes
2) Protozoa develop in mosquito
3) Sporozoites migrate to salivary glands
4) Inoculated into human host, taken up by liver
5) Multiply in hepatocytes to form merozoites
6) Hepatocytes rupture and merozoites released into blood
7) Merozoites multiply and form trophozoites, schizont and new merozoites inside erythrocytes
8) A few merozoites develop into gametocytes which are taken up by other mosquitos

47
Q

Give 3 things protozoa multiplying in RBCs causes

A
  • ) Haemolysis
  • ) RBC sequestration
  • ) Cytokine release
  • ) Infect liver
48
Q

What do fever paroxysms reflect in malaria?

A

Synchronous release of merozoites from mature schizonts, causes cold/hot fever and nausea/headache

49
Q

Give 2 protective factors for malaria

A
  • ) Glucose 6 phosphate dehydrogenase deficiency

- ) Sickle cell trait

50
Q

Give 3 symptoms of malaria

A
  • ) 90% present within 1 month
  • ) Prodromal headache, malaise, myalgia, anorexia before 1st fever paroxysm
  • ) Tertian fevers - recur every second day is classic
  • ) Anaemia, jaundice, hepatosplenomegaly
51
Q

What can decreased consciousness indicate in malaria?

A

Cerebral malaria

52
Q

What is the mortality for falciparum malaria?

A

20%

Higher if very young/pregnant

53
Q

Give 3 tests we do for malaria

A
  • ) Serial thin and thick blood films to show level of parasiteaemia
  • ) FBC may show anaemia (from haemolysis) and thrombocytopaenia
  • ) Clotting, glucose, ABG/lactate, U&E, urinalysis
  • ) Blood culture to check for septicaemia
54
Q

How do we treat P. falciparum malaria? (5)

A
  • ) Combination therapy containing artemisinin derivatives
  • ) Possible atovaquone-proguanil (macaroni)
  • ) Or quinine and doxycycline/clindamycin
  • ) P. falciparum largely resistant to chloroquine
  • ) IV with artesunate if severe (with above)
55
Q

How do we treat uncomplicated P. ovale/vivax/malariae malaria?

A
  • ) Chloroquine based
  • ) Primaquine after in ovale and vivax to prevent relapse
  • ) Malarone or quinine if resistant
56
Q

What is the general treatment for malaria?

A
  • ) Paracetamol
  • ) Transfuse if severe anaemia
  • ) Monitor bloods
57
Q

How do we prevent malaria?

A
  • ) Proguanil daily and chloroquine base weakly
  • ) If chloroquine resistant - doxycycline or malarone
  • ) Repellant, long sleeves, bed nets
58
Q

What is malarone?

A

Atovaquine-proguanil

59
Q

What is a lymphoedema?

A

Chronic non-pitting oedema due to lymphatic insufficiency

60
Q

What part of the body does a lymphoedema normally affect?

A

Legs

61
Q

What can chronic lymphoedema cause?

A

Secondary ‘cobblestone’ thickening of skin

62
Q

Give a primary cause of lymphoedema

A

Milroy disease

63
Q

Give a secondary cause of lymphoedema

A

Obstruction of lymphatic vessels

64
Q

What is Milroy disease?

A

Lower leg swelling from birth, autosomal dominant

65
Q

What are the mutations in Milroy disease?

A

VEGFR3 causing lymphatic malfunction

66
Q

What is the treatment for Milroy disease?

A

Compression stockings/bandages, exercise

67
Q

What is a filarial infection transmitted by?

A

5 genera of mosquito

68
Q

What does a filarial infection cause?

A

Obstruction of the lymphatic vessels

69
Q

Give 2 symptoms of an acute filarial infection

A

Fever
Lymphadenopathy
Chyluria

70
Q

What can a filarial infection also cause?

A

Elephantiasis - massive lymphoedema in the legs and massive hydroceles

71
Q

What can a sarcoma originate from?

A

Any mesenchymal tissue (fat/muscle/cartilage/bone)

72
Q

What do soft tissue sarcomas present as?

A

Painless enlarging mass

73
Q

Give a risk factor for a sarcoma

A

Neurofibromatosis, previous radiotherapy

74
Q

Give 2 features that will lead a lump being considered malignant

A
  • ) Lump bigger than 5cm
  • ) Increasing in size
  • ) Deep to deep fascia
  • ) Painful
75
Q

How do we diagnose a sarcoma?

A

MRI followed by needle biopsy

76
Q

What is the most common sarcoma in children?

A

Rhabdo-myosarcoma

77
Q

Give 2 types of sarcoma

A

Rhabdo-myosarcoma, liposarcoma, leiomyosarcoma, fibrosarcoma

78
Q

How do we treat sarcomas?

A

Exision with wide margins followed by radiotherapy

79
Q

What would we use chemotherapy in a sarcoma?

A

Osteosarcoma or mets

80
Q

What is the general management for poisoning? (7)

A
  • ) ABC, secure airway, shock
  • ) Take blood, paracetamol and salicylate levels
  • ) Possible empty stomach
  • ) Consider specific antidote or oral activated charcoal
  • ) Get more info, TOXBASE
  • ) Monitor closely and give supportive care
  • ) Psychiatry?
81
Q

What does CO do?

A

Binds to Hb and decreases O2 delivery to tissues

82
Q

Give 3 symptoms of CO poisoning

A
  • ) Headache
  • ) Vomiting
  • ) High pulse
  • ) Tachypnoea
  • ) Fits, coma, cardiac arrest if severe
83
Q

What does an ABG show in CO poisoning?

A

Low O2 saturation and high carboxyhaemoglobin

84
Q

How do we treat CO poisoning?

A

Remove source and give O2 until carboxyhaemoglobin decreased

85
Q

How do we treat cerebral oedema?

A

Mannitol

86
Q

What does aspirin/salicylate poisoning do?

A

Uncoupling of oxidative phosphorylation leading to anaerobic metabolism and production of lactate and heat

87
Q

Give 3 symptoms of salicylate poisoning

A
  • ) Vomiting
  • ) Dehydration
  • ) Hyperventilation
  • ) Tinnitus
  • ) Vertigo
  • ) Sweating
  • ) Low GCS, low BP, seizures, hyperthermia, pulmonary oedema rarely
88
Q

What sort of alkalosis is there in salicylate poisoning?

A

Initial respiratory alkalosis then metabolic acidosis

89
Q

How do we treat salicylate poisoning?

A
  • ) Correct dehydration
  • ) Give activated charcoal within 1 hour
  • ) Monitor bloods
  • ) Correct acidosis
  • ) Treat hypokalaemia if present
  • ) Dialysis if severe and if complications
90
Q

Give a complication of salicylate poisoning

A

AKI, HF, oedema, confusion, seizures

91
Q

How do we correct acidosis?

A

IV sodium bicarbonate

92
Q

Give 2 symptoms fo paracetamol poisoning

A
  • ) Nothing initially
  • ) Vomiting
  • ) RUQ pain
  • ) Jaundice and encephalopathy later
  • ) Possible AKI
93
Q

How do we treat paracetamol poisoning?

A
  • ) Activated charcoal within 4 hours

- ) N-acetylcyseine within 10-12 hours and no vomiting

94
Q

What do organophosphate insecticides cause?

A

Inactivate cholinesterase and thus increase acetylcholine

95
Q

Give 4 symptoms of organophosphate insecticide poisoning

A
  • ) SLUD - salivation, lacrimation, urination, diarrhoea
  • ) Sweating
  • ) Small pupils
  • ) Muscle fasciculation
  • ) Coma
96
Q

How do we treat organophosphate insecticide poisoning? (3)

A
  • ) Remove soiled clothes and wash skin
  • ) Atropine IV until fully atropinates
  • ) Pralidoxime and diazepam
97
Q

What does atropinates mean?

A

Skin dry, pulse >70, pupils dilated