Infectious Disease + Micro Flashcards
What is the function of node like receptors?
Purpose is to detect intracellular microbial pathogens.
Stimulate the release of cytokines and cause cellular apoptosis
Give 3 examples of pattern recognition receptors?
Toll Like receptors
Rig like receptors
Nod like receptors
What are the purposes of pattern recognition receptors such as node like receptors and toll like receptors?
Amplify the immune response.
What are 3 functions of antibodies?
Opsonisation
Neutralise toxins
Activate complement system
What is the function of complement factors?
Recruit and activation of macrophages, neutrophils and other WBC
What are the 4 stages of growth in liquid media?
- Lag Phase
- Log Phase
- Stationary Phase
- Decline Phase
DO gram negative or gram positive bacteria produce more endotoxin??
Gram positive. Hence why it causes more serious damage
Describe the following:
Active immunisation:
Passive immunisation:
Active immunisation: stimulates virgin lymphocytes to be stimulated to make antibodies
Passive: ready made antibodies injected into body
Define
infectivity
Virulence
Infectivity: the ability to become established in a host
Virulence: the ability a pathogen has at eliciting a disease
What are the 3 components of an outer component of a Gram negative bacteria ?
Lipid
Core R antigen
Somatic O antigen
Which strain of HIV is more prevalent in humans?
HIV 1
Give the name of two receptor types on the service of a HIV virus?
G120 and G41
What is the CD4 count in a patient with HIV?
What is the CD4 count in a patient with AIDS?
CD4 in HIV >400
CD4 in AIDS >200
How many genes make up the HIV virus?
7
What is the pathophysiology behind HIV and its replication?
The HIV virus attaches to a cell via its receptors G41 and G120
The HIV then de envelopes and releases reverse transcriptase that causes viral RNA to be transcribed and then spliced.
Virions are then released out of the cells. They are undetectable as are surrounded by host cell.
Constantly mutates
How would you describe the immunogenicity of HIV?
Does it have genetic diversity?
Poor immunogenicity
YES it does
What are 3 cells affected by HIV?
Macrophages
CD4 T cells
Dendritic cells
What are some features of an acute infection of HIV?
- Fever
- Weight loss
- Sweating
- Malagia and Lymphadenopathy
What are some symptoms of secondary infection of HIV?
Signs of malignancy: cervical cancer, non Hodgkin’s lymphoma and also kaposi sarcoma.
Signs of infection: TB, pneumonia and diarrhoea
Weight loss, generalised lymphadenopathy and candida
How do you monitor the levels of HIV via the blood? (3 ways)
CD4 levels
P24 antigens
Via saliva or blood glucose test
How do you manage HIV?
HAART therapy: anti-retro virals such as tenofovir and abacavir
What are the 3 different types of Protozoa?
- Flagellates
- Amoebae
- Sporozoans
What class are the malaria’s part of protozoa wise?
- Sporozan
Give 5 steps that a virus needs to replicate?
Attachment
Cell entry
Interaction
Replication
Assembly
Vision Release
What are 5 ways that a virus can cause disease?
- Direct damage to the host cell
- Damage by modification of cell function or structure
- Physical modification
- Functional Modification
- Damage by over reaction
Damage through cell proliferation and immortalisation
What are interferons?
Chemokines that have anti-viral properties
What are the 3 groups of Helminths?
Cestode: tape worm
Nermatode: flat worm
Trematode: round worm
What is an example of a flat worm?
Liver, lung or blood flukes
Schistosomiasis
How do you treat the nermatode thread worm?
Mebendazole
What type of cell is a fungi?
Eukaryotic
How would you describe:
- Yeast
- Mould
Yeast is a single cell organism that divides by budding
Mould is a multi cell organism that divides by sported
What do you need to stain a fungal culture with?
KOH
How would you describe a mycobacteria ?
- Aerobic
- Non sporting
- Non motile
What is the difference between intrinsic and extrinsic antibiotic resistance?
Intrinsic naturally occurs and is passed on
Extrinsic passed on by horizontal gene transfer and spontaneous gene mutation
What is the main aetiology behind Hep B?
Vertical transmission
What is the main aetiology behind Hep C ?
IVDU
If a patient had an active infection of Hep B what antigens would be present in their blood?
Hep B surface antigen
Of Hep B envelope antigen (less specific)
What antibody would be present in a patient who has had a Hep B immunisation or post infection?
Hep B surface antibody
If a patient had a Hep B core antibody present in their blood what would it suggest?
They have an acute, chronic or past infection of Hep B
Is not present in a patient who has had the vaccination.
What time period is classed as chronic in Hepatitis B?
More than 6 months.
What are two complications of Hep B?
Liver cirrhosis and hepatocellular cancer as Hep B is an oncogenic virus
What is the management of Hep B?
You need to give the anti viral tenofovir
used to use Pegylated interferon alpha
Is hep B DNA or RNA?
DNA
What monitoring tests are need in someone with chronic viral hepatitis?
Alpha fetoprotein
US monitoring
Fibroscan and possibly Liver biopsy. Need to check viral markers
If a patient was Hep C. Is the virus DNA or RNA?
RNA
What medication do you give someone who has Hep C ?
Direct Acting Anti-viral Drug (DAA) aka elbasvir
What are two medications used in life threatening COVID?
Remdesevir
Dexametasone
What anti coag would you want to give to a COVID patient?
- Stop warfarin and DOAC
2. Start LMWH
What are 3 tests you could do in a patient with suspected latent TB?
- Mantoux Test
- IGRA test
- CX-Ray
What are two SE of rifampicin?
Red urine + Tears and Hepatitis
What are two SE of isoniazid?
Hepatitis , peripheral neuropathy
What anti-TB drug affects the COCP?
Rifampicin
In latent TB what is the treatment?
Rifampicin and Isoniazid for 3 months each
What is the management for a patient with active TB?
You need 2m of Rifampicin and Isoniazid + Pyrazinamide + Ethambutol
4m of Rifampicin + Isoniazid
Which of the anti TB drugs is bacterialcidal? What is a SE of this?
Ethambutol
optic neuritis
What medication can you not take with HAART?
Omeprezole
Which Hepatitis Virus’ can you vaccinate against?
Hep A and B
When is a patient with Hep C ‘cured’?
When their HCV RNA levels are negative after 12 w of stopping meds
What class of drug is used to treat Hep C?
DIrect Acting Anti-Viral Drugs
When would a Hep B envelope antibody be present in?
In a patient who has had or has the virus
If a pregnant lady is positive for Hep B what do you do post labour to the baby?
You give Hep B antibodies
What is the definition of sepsis?
Life threatening organ dysfunction due to a dysregulated host response to an infection.
What other virus does Hep D need to survive?
Hep B
What antibiotic is used to treat staph infections?
Flucoxicillin
What antibiotics are used to treat listeria?
Amoxicillin + gentamicin
What is the abx you need to use for someone with klebseilla?
Cefotaxime
What is the abx treatment for helicobacter pylori?
Clarithromycin and Amoxicillin
What virus will you see owl eye inclusion bodies on microscope?
Cytomegaly
What virus will you see inclusion bodies in ?
Herpes Simplex Virus
What agar should you use for candida growth?
Sabourad Agar
Give an example of a cephalosporin abx?
Ceftotaximine
What is an example of a carbapenm? What is it useful in?
Resistant bacteria both -ve and +ve
Example: meropeneum
What is an example of a macrolide?
Erythromycin
Example of an aminoglycoside?
- Streptomycin
2. Gentamicin
