IHD EXAM QUESTIONS Flashcards
Peptic ulcer symptoms
Haematemesis
Epigastric pain which can radiate to the back
Dysphagia
Complications of a peptic ulcer
Perforations
Bleeding (haematemesis)
Gastric cancer
Weight loss due to dysphagia
How can H. Pylori survive in the stomach and cause ulcers?
Produces urease which converts urea into ammonia and CO2. Travels through to stomach protected by ‘cloud’ of urease
- survives in mucin layer of stomach
- here it causes rupture to endothelial cells, leading to ulceration of lining of the stomach
Causes of facial palsy
oIDIOPATHIC – BELLS PALSY
oINFECTION – TB, RAMSAY HUNT SYNDROME, GLANDULAR FEVER AND AIDS
oTRAUMA – FACIAL LACERATION AND POST PAROTID SURGERY
oNEOPLASTIC – PRIMARY OR SECONDARY CANCER, NEUROMA OF THE FACIAL NERVE AND ACOUSTIC NEUROMA
oMETABOLIC – DIABETES, PREGNANCY, SARCOIDOSIS AND GUILLAIN-BARRE SYNDROME
oIATROGENIC – LA INJECTION
Difference between UMN and LMN
oUPPER MOTOR NEURONE IS ABOVE ANTERIOR HORN CELL
oLOWER MOTOR NEURONE INDICATES IS EITHER IN ANTERIOR HORN CELL OR DISTAL TO ANTERIOR HORN CELL
Vesicles on external auditory meatus and treatment
oOCCURS IN RAMSAY HUNT SYNDROME (HERPES ZOSTER OTALGIA)
oTHE GENICULATE GANGLION OF FACIAL NERVE INFECTED WITH HERPES ZOSTER
oTREATMENT: ACYCLOVIR
TREATMENT FOR RHEUMATOID ARTHRITIS
o DMARDS e.g. methotrexate
o NSAIDS – anti-inflammatory and analgesic
o Steroids – anti-inflammatory e.g. prednisolone
o Biological drugs e.g. anti-TNF agents
SYSTEMIC MANIFESTATIONS OF RHEUMATOID ARTHRITIS
o LUNGS – LUNG FIBROSIS, NODULES, PLEURAL EFFUSIONS
o CARDIOVASCULAR – PERICARDIAL INFLAMMATION< MYOCARDITIS AND VALVE INFLAMMATION
o RENAL – AMYLOIDOSIS
o LIVER – HEPATIC IMPAIRMENT
o SKIN – PALMAR ERYTHEMA AND SUBCUTANEOUS RHEUMATOID NODULES
TREATMENT WHILST WAITING FOR AMBULANCE MI
300mg oral aspirin - chew and swallow
Oxygen/ nitric oxide 50/50 ratio - inhaled
GTN spray sublingually, can repeat after 10 mins
Tests for MI
Angiogram (USS)
Myocardial perfusion scan
Blood test for raised troponin
Elevated ST indicates STEMI MI
Why does pt have to wee more in diabetes type ii?
o HIGHER GLUCOSE CONCENTRATION IN BLOOD
o SO MORE IS EXCRETED AS CANNOT BE ABSORBED
o WATER MOVES OUT WITH GLUCOSE INTO NEPHRON DOWN THE OSMOTIC GRADIENT
o AS MORE WATER IS REMOVED, THERE IS AN INCREASED RATE OF URINARY EXCRETION
4 meds GP could prescribe for type ii diabetes
o METFORMIN (BIGUANIDE) o GLICLAZIDE (SULFONYLUREA) o INSULIN o STATINS o ANTIHYPERTENSIVES
Long term complications of diabetes type ii
o MACROVASCULAR STROKE MYOCARDIAL INFARCTION PERIPHERAL VASCULAR DISEASE o MICROVASCULAR DISEASE DIABETIC RETINOPATHY DIABETIC NEUROPATHY DIABETIC NEPHROPATHY
Why is haemostasis impaired in liver disease?
o LIVER PRODUCES CLOTTING FACTORS
o HYPERSPLENISM: IN PORTAL HYPERTENSION (IN CLD), THERE IS BACKLOG OF PRESSURE INTO SPLENIC VEIN. AS A RESULT SPLEEN ENLARGES, REDUCING NUMBER OF PLATELETS AND WBCS. THIS LEADS TO THROMBOCYTOPENIA (INCREASED RISK OF BLEEDING), AND NEUTROPENIA (SO PERSON IS MORE SUSCEPTIBLE TO INFECTION)
5 things you can do in dental practice to stop haemorrhage after XLA and standard measures
o TRANEXAMIC ACID MOUTHRINSE 5% 5ML, 5-10 MINS POST-OP, QDS, KEEP IN MOUTH FOR 2 MINS THEN SPIT FOR 5 DAYS
o IF BLEEDING, HORIZONTAL MATTRESS SUTURE
o OXIDISED CELLULOSE
o GAUZE, BITE DOWN ON IT
o GELATIN SPONGE
o CLOTTING FACTOR CONCENTRATE
o CRYSTALLOID
Causes of hepatic cancer
Smoking Alcohol Diabetes Hypertension Hyperlipidaemia
5 investigations for kidney
o GLOMERULAR FILTRATION RATE: MEASURING INSULIN CLEARANCE AND CREATININE LEVELS
o FULL BLOOD COUNT – UREA, CREATININE
o URINE ANALYSIS FOR PROTEINURIA AND HAEMATURIA
o CT/ ULTRASOUND
o RENAL BIOPSY
Calcium metabolism and kidney disease
o LESS CA2+ REABSORPTION IN KIDNEYS SO LOWER CALCIUM IN BLOOD
o REDUCED PRODUCTION OF VITAMIN D, SO LOWER PRODUCTION OF CALCITRIOL. THEREFORE LOWER INTESTINAL ABSORPTION OF CALCIUM. PTH PRODUCTION INCREASES TO COMPENSATE FOR LACK OF CALCITRIOL. INCREASED PTH PRODUCTION LEADS TO INCREASED BONE RESORPTION.
Cyclosporine after transplant - which antibiotic can you not prescribe and why
o ERYTHROMYCIN IS CONTRA-INDICATED WHEN PT HAS RENAL TRANSPLANT AND TAKING CYCLOSPORIN AS ITS METABOLISM IS REDUCED LEADING TO INCREASING TOXICITY
o ERYTHROMYCIN INACTIVATES CYP3A, WHICH PROCESSES MANY DRUGS. CYCLOSPORIN PROCESSED BY CYP3A. AS IT IS INHIBITED, CYCLOSPORIN CAN’T BE BROKEN DOWN THEREFORE REACHES TOXICITY.
Reasons for taking bisphosphonates
o OSTEOPOROSIS
o PAGETS DISEASE
o BONE METASTASIS
oHYPERPARATHYROIDISM
MRONJ tx pathway
o CHLORHEXIDINE MOUTHWASH
o DEBRIDEMENT – REMOVE SHARP BONY EDGES AND GRANULOMATOUS TISSUE ETC. – CULTURE AND CHECK FOR ACTINOMYCES
o ORAL HEALTH EDUCATION
o ANTIBIOTICS IF INFECTED
o SUTURE AFTER XLA TO GET MUCOSAL COVERAGE
o POTENTIAL DRUG HOLIDAY IF THEY’RE ON BISPHOSPHONATE – NOT FOR MALIGNANCY
o KEEP REVIEWING PT
Gonorrhoea virulence factors
o PILI – ATTACHMENT
o OPA OUTER MEMBRANE PROTEINS FOR ADHESION AND PREVENTS IMMUNE RESPONSES
o LIPOOLIGOSACCHARIDES – HOST MIMICRY
o PORIN B PROTEINS – BACTERIAL INVASION
o IGA PROTEASES – ALTERS LYSOSOMAL ENZYMES
Action of penicillin
o B LACTAM
o INHIBITS CROSS LINKAGES OF PEPTIDOGLYCAN
o THIS PREVENTS CELL WALL FORMATION
Organism likely to cause pneumonia in pt with HIV
o PNEUMOCYSTIS JIROVECI
BVV defining features
- WELL DEFINED, PEARLY EDGE, MAY CRUST THEN APPEAR TO REGRESS, SLOW GROWING
- SURGERY (4MM MARGIN)
- RADIOTHERAPY
- IMIQUIMOID (IMMUNE STIMULATION)
Which sites are appropriate for pulse oximetry?
Fingers
Toes
Ear lobes
Bridge of nose
What percentage of the diagnostic pyramid is made up by special investigations?
5%
List 5 tests that can be carried out in the lab to aid diagnosis/ study of anaerobes.
- Gram stain
- Spore stain
- Sensitivity to metronidazole
- Sugar fermentation
- Toxin production
- Gas- liquid chromatography
- RNA sequencing
Molar tooth colonies when culturing produced by which species
Actinomyces
Why can actinomyces often present at angle of the mandible?
Associated with traumatic extraction of lower 8s
Properties of S. pyogenes
Lancefield A - beta-haemolytic
Gram positive
Facultative anaerobe
Catalase negative
Which HHV is described as have slow growth primarily in T cells and lymphocytes, and which viruses belong to this classification?
Beta herpesvirus
Cytomegalovirus and HHV7
A typical CSF change in an individual who has developed bacterial meningitis is:
Elevated protein
What beneficial activity can commensals in the GI tract do
a) They can degrade toxins we are unable to degrade ourselves
b) They can help us absorb vitamins
c) They stimulate the immune system to keep it on top form
Antimicrobial action of metronidazole
Interference with nucleic acid synthesis or function
What is the treatment of paracetamol overdose and by what mechanism does it work?
N-acetyl-cysteine donates cysteine for synthesis of glutathione
What is the max time after paracetamol overdose for minimal liver damage?
Within 12 hours
Name 3 medications that increase the plasma concentration and effect of
warfarin?
Erythromycin
Miconazole
Metronidazole
What does a high Vd (volume of distribution) mean?
Drug highly bound to cell plasma
What is the bioavailability of a drug?
The ‘bioavailability’ of a drug is the fraction of a dose reaching the systemic circulation
after oral dosing. Determined by: Absorption/ FP metabolism
How can we reduce the risk of adverse effects of drugs on a patient?
a. Never use a drug unless indicated
b. Use as few drugs as possible, therefore limiting interactions
c. Check for any allergies
d. Check the patient isn’t taking any other medication (including OTC drugs)
How do NSAIDs work, why do they cause so many side effects and what are common side effects?
a. They work by blocking the COX enzyme, which prevents prostaglandin synthesis
b. However, since COX enzymes (especially COX-1) are found throughout the
body, there are a huge range of side effects
c. Side effects include, commonly, GI disturbance, indigestion and diarrhoea –
HENCE PRESCRIPTION OF A PPI. As well as oedema, dizziness, renal failure, heart failure.
Side effects of gabapentin
Drowsiness
Parasthesia
Ataxia
Erythromycin class
Macrolide
Name 3 ways in which antimicrobial resistance occurs:
Target is structurally altered (mutation) The target is overproduced The drug is not activated The drug is removed The drug cant gain entry to the cell
What is the definition of antibiotic resistance?
An organism that is not inhibited or killed by an antibacterial agent at concentrations of
the drug achievable in the body after normal dosage.`
Aminoglycoside action
b. Not effective against anaerobes
c. Contain an aminocyclitol ring linked to sugar
d. Requires oxygen for bacterial uptake
List and describe the basic components of a cardiovascular examination.
Pulse, (rate/rhythm/character), Blood pressure, JVP, (if increased then likely right
sided heart failure), Peripheral and pitting oedema, Auscultation, Finger nails (for
evidence of infective endocarditis)
A 65 year old male patient attends your practice. He had a myocardial infarction two
months prior but his angina is now controlled with several medications; he also has a
metal heart valve. You notice a new carious lesion in the UR4 and the LL6 is heavily
broken down and requires extraction. How would you manage this patient and what
precautions would you take?
Avoid any treatment for at least 6 months after an MI. Care should be taken when
the patient returns for treatment with local anaesthetics and the cardiac effects of
adrenaline; either limit to 2 cartridges or use prilocaine with felypressin. Care should
also be taken as the patient is at risk of infective endocarditis and he should be
warned to be wary of this, but not given prophylactic antibiotics. When extracting
the LL6 care should be taken as the patient is likely to be on oral anticoagulants
such as warfarin so an INR check will be needed and must be between 2-4.
A gentleman has been diagnosed with chronic ischaemic valve disease and valvular
stenosis. Please discuss possible future treatment and management of this patient.
- Management of lifestyle- reducing salt to reduce associated BP problems,
- Reduce saturated fats to reduce ischemic heart disease from advancing.
- Slowly increasing exercise regime.
- Drugs- e.g. diuretics/ACE inhibitors/angiotensin receptor antagonist all possible to
reduce blood pressure. - Warfarin- reduce chance of blood clotting and thrombosis forming
- Digoxin- slows down the heart rate and strengthens the beat. allowing more
efficient pumping. - GTN spray for possible angina attacks
- Future surgery- coronary bypass surgery, valvular replacement, pacemaker fitted
Why should an aspirating technique be used when giving a patient with AF and IAN
block
Aspiration insures not injecting into a blood vessel.
if LA contains adrenaline can have systemic effects on the heart
Increase the force of contraction, and the rate of the heart.
Potentiate any existing heart diseases or even cause AF, increase in BP.
accurate description of Type II respiratory failure
A resulting from an inability to exchange gases at the alveoli, resulting in metabolic acidosis
due to retained CO2, resulting in warm extremities. A common cause would be cerebral
hemorrhage.
What produces pink frothy sputum?
Pulmonary oedema
Methylxanthamines are a type of bronchodilator used in the treatment of asthma. By
which process does it achieve this?
Inhibition of phosphdiesterase
Causes of community acquired pneumonia
M. catarrhalis
S. pneumoniae
H. influenzae
Different treatments for atopic asthma and their action
Steroids (1) - have an anti-inflammatory effect, reducing the inflammatory response
by binding to receptors (1)
Mast cell stabilizers (1) - prevent the release of histamine (1)
β 2 -receptor agonists (1) -act onadrenergic receptors causing dilation of bronchioles
(1)
Avoiding the antigen (1)
What is emphysema?
Anatomical enlargement of airspaces distal to the terminal bronchioles (1) with
destruction of elastin in walls (1)
What does S. pneumoniae cause?
Pneumonia
Otitis media
Sinusitis
Meningitis
What special investigations would you take if pneumonia was suspected?
- Full blood count
- Chest Xray
- Oximetry
- Sputum Test
- Bronchoscopy
Which bacterium requires factor V and X?
Gram negative H. influenzae
Name a muscarinic inhibitor
Tiotropium
List the adjunct therapies available when treating asthma.
Leukotriene antagonists
Cromones
Anti-Ig therapy
Outline how is asthma treated, progressing from mild to severe cases. How does
this compare to the treatment of COPD?
As severity increases more drugs are added. Asthma: -SABA -SABA + ICS -SABA + ICS + LABA -SABA + ICS + LABA + 4 th drug COPD: -SABA -SABA + LABA -SABA + LABA+ ICS -SABA + LABA+ ICS + LAMA
A patient suffers from loss of vision. You did an examination of the patient. What
other questions would you ask regarding character of the vision loss?
Transient or continuous
Profound or mild
Rapid or slow onset
Central or
peripheral
One or both eyes
Affecting colour, contrast, night vision.
A chalazion is:
granuloma affecting meibomian gland
Main component of Hep B vaccine
Genetically engineered HBsAg
How is Hep C treated?
Interferon alpha and ribavirin
Kidney functions
Salt and water homeostasis Excretion of waste products Selectivity barrier Humoral balance -vit D processing -erythropoeitin production -renin productin (regulates blood pressure)
Campylobacter spp. leads to
Diarrhoea
Ulceration of jejenum
Reactive arthritis
Guillaime-Barre syndrome (muscular weakness)
(it is gram negative and symptoms last up to 3 weeks)
Name 3 important patient variables to consider in your pre-anaesthesia assessment.
Age, sex, fitness, diagnosis of ischaemic heart disease/heart failure/brain
disease/kidney failure.
What can you advise patients to take once local anaesthesia wears off?
Generally paracetamol plus an NSAID. “What they take for a headache” is usually
sufficient.
What are the 5 primary survey steps in Advanced Trauma Life Support?
A:Airwaymaintenance +C-spineprotection B:Breathing& Ventilation C:Circulation& Haemorrhage control D:Disability– Neuro E:Exposure/ Environment control
A 20 year old pedestrian has just been knocked over by a car at speed, you are first
to their aid. The pedestrian is conscious but pale, restless and sweating, there is no
evidence of blood loss.
a) Could you suspect haemorrhagic shock and why? (1 mark)
b) You manage to take their blood pressure and this is normal, would this change what
you initially suspected? (1 mark)
c) In this situation, what sign is a good indicator of haemorrhagic shock? (1 mark)
A) Yes, there maybe internal trauma: NB abdominal/retroperitoneal/intrathoracic blood loss
B) No: A fall in BP is alatesign of haemorrhagic shock - especially in young people.
C) Tachycardia: especially if sustained and prolonged
How does general anaesthesia work?
Neuronal membrane deformation • Inhibit neurotransmission Specific receptor blockers • GABA (inhibitory neurotransmitter) • Glycine (inhibitory neurotransmitter)
Which medical diseases may influence the type of general anaesthesia used?
Cardiovascular (GA effect = depression) Respiratory (GA effect = depression) Cerebral Renal (no issue with inhalational) Hepatic Diabetes - Danger is Unrecognised hypoglycaemia under GA
How does local anaesthesia work?
Prevent conduction of impulses by nerve fibres
Un-ionised fraction diffuses in setting up a concentration gradient for ionised form to
diffuse in
Resting potential of nerve is -60mV to -90mV
In the nerve, as the [LA] rises, Rate of depolarisation falls and nerve conduction slows
Inhibits influx of sodium through voltage gated ion channels, preventing action potential.
What is the combination used for induction chemotherapy?
Cisplatin, 5FU, Docetaxel
List the possible risk factors for the occurrence of Head & Neck Cancers.
Smoking
Alcohol
Diet and Nutrition
Viruses - Human Papillomavirus or Epstein Barr Virus
Immunosuppression
Premalignant oral conditions - Leukoplakia, Lichen sclerosis Radiotherapy exposure
What is the average energy of a photon used in the radiotherapeutical treatment
of Squamous Cell Carcinoma
100kPa
Name a H&N cancer that is also a cancer of the skin
Merkel Cell Tumour
Prognostic marker for melanoma
BRAF mutation
A 65 year old patient presents with large tense blisters and itchy rash. He also has
blisters in the mouth. What is the likely diagnosis?
Pemphigoid
Which immunoglobulin is associated with the dermatological disorders
pemphigoid and pemphigus?
IgG
What medication cannot be used in pregnancy
Miconazole
A female patient walks into your clinic. She informs you she is on her second
trimester. What can you infer about her respiratory output?
Increased pO2
RR unchanged
Tidal volume increased
Alkalosis
Side effects of lithium
Tremor
Thirst
Hypothyroidism
What does chlorpromazine do
Antipsychotic (schizophrenia)
What is given to patients on methotrexate to prevent mouth ulcers as a side effect?
Folate
Cytology can be used to safely diagnose pathology in the thyroid gland. However
this test is unable to differentiate between the malignant and benign type of which of
the following potential thyroid gland lesions?
Follicular
A patient presents with central weight gain, acne, and purple striae in the abdomen
area.
a) What do you suspect the patient has?
b) What tests would you send them for?
a - Cushing’s Syndrome
b - Hormonal tests of cortisol – (dynamic suppression tests – where you attempt to
suppress the cortisol level, if not suppressed then there is a problem. Also measure ACTH
and if it is decreased then the problem is in the adrenal glands, if it is increased the
problem is in the pituitary). If hormonal tests are abnormal then you send for radiological
analysis.
Increase in ACTH = send for MRI of pituitary.
Decrease in ACTH = send for CT of adrenals.
What does sulphonylurea do?
Blocks K+ entry into beta cells, leading to membrane
depolarisation. This leads to Ca2+ influx, causing
secretion of insulin from pancreatic b cells
What does metformin do?
Increases cellular insulin sensitivity so increases
uptake of glucose into cells. Decreases glucose
reabsorption in the intestines. Decreases liver
production of glucose.
Which STI increases your likelihood of contracting HIV by 5 times?
Gonorrhoea
List 3 strong associations of chlamydia infection in men
- Acute epididymitis
- Prostatitis
- Infertility
List the different stages of syphilis, giving a brief summary of each stage
- Primary stage: Marked by appearance of single chancre (but can be multiple) which
lasts for 3-6 weeks and heals without treatment - Secondary stage: Characterised by non-itchy skin/mucous membrane rash. Other
symptoms include fever, swollen lymph nodes, sore throat, patchy hair loss, headaches,
weight loss, muscle aches and fatigue. All resolve without treatment. - Latent stage: No signs/symptoms. Disease damages internal organs
Name 3 cardiovascular complications of haemodialysis and
CAPD?
K related arrhythmias
Hypertension
Cardiac valvular complications
A patient has been diagnosed with a UTI - there is no change when the sample is
cultured on MacConkey agar. On a microscope slide purple groups of cocci can be
seen. When the organism is added to a blood sample, the blood does not coagulate. In
a sensitivity test the organism is resistant to novobiocin. What organism has cause
this UTI?
Staph. saprophyticus
What type of treatment is there for mild/moderate renal failure?
Diet (restrict things such as potassium and phosphate in the diet because the kidney
cannot get rid of them)
Supplements- Alkali, Vitamin D and Iron
Drugs- Phosphate, hypertension and anaemia
4) A patient attends your clinic during the history taking they inform you that they
suffer from Addison’s disease and are taking 20mg Hydrocortisone daily.
a) What is Addison’s disease?
b) They require an extraction, why is their history important?
a - An autoimmune condition causing primary adrenal insufficiency. It disrupts the
production of aldosterone and cortisol.
b - They are at risk from adrenal insufficiency (can lead to cardiovascular collapse).
- Need to double dose of hydrocortisone one hour before the extraction and then
double the oral dose for 24 hours after.
Choose the correct answer.
CRM 5 year survival
rate
Local recurrence A + 10% 75% B + 20% 85% C - 75% 20% D - 85% 10%
B
What stages does the epithelium of the colon go through to develop into a
serious GI condition?
Normal epithelium > Adenoma > Colorectal adenocarcinoma > Metastatic colorectal
adenocarcinoma
What is the 5 year survival rate of a 42 year old female with oesphageal cancer 5
years after diagnoses?
18%
Nephritic vs nephrotic
Nephritic: haematuria
Nephrotic: proteinuria
Why can’t you give a pt with renal impairment NSAIDs?
not cleared/increased bleeding – inhibiting prostaglandins may lead to kidney failure
Side effects of gentamicin
Hearing loss
H. influenzae vaccine
Hib type B combination vaccine
Causes of diarrhoea with blood
E. coli
Salmonella
Shigella
Campylobacter
Liver functions
Bile production Immune functions -fighting infections -RE system Regulation of glycogen metabolism Detoxification of drugs, hormones, waste products Energy storage (fat, glycogen) ability to Regenerate Synthesis of fats, enzymes, proteins (albumin), coagulation factors
What type of vaccine is Hib
Recombinant polysaccharide conjugate vaccine
Nappy rash is caused by
-treated by
Strep pyogenes?
-if strep pyogenes, would be treated by penicillin
Rust coloured sputum
Pneumonia, pulmonary embolism, lung cancer, pulmonary TB
Purpura rash, CSF= neutrophils, high protein, low
glucose, gram-ve diplococci
Neisseria meningitidis
CD4/CD8 levels test in HIV?
Flow cytometry
Symptoms of uraemia
Vomitting Confusion Nausea Pruritis Fatigue Weight loss/ anorexia
Side effects of tricyclic antidepressants
Dry mouth
Blurred vision
Sweating
Dizziness
Pt has been on dialysis that day and has bled more during
on extraction why is this?
Heparinisation
Pt has TB which drugs?
-vaccine
Rifampicin and isoniazide for 6 months
Pyrazinamide and ethambutol for 2 months
BCG vaccine
Pt had haemoptysis, upper lesions on CXR weight loss
which bacteria caused this?
TB
How does grapefruit juice influence drugs
Grapefruit juice is a CYP450 inhibitor so drugs that are metabolised by this enzyme cannot be and levels rise potentially to toxic levels in blood
Neck lump that gets worse with alcohol
Hodgkins lymphoma
Asthma mechanism
- Hypersensitivity reaction type 1
- IgE mediated, rapid onset, if higher levels of IgE then more susceptible
- Allergen binds to specific IgE on mast cells causing cross linking of IgE bound receptors
- Degranulation of mast cells with release of inflammatory mediators and histamine
- Histamine release causes bronchoconstriction, mucosal inflammation, mucous hypersecretion
3 medications for asthma and how they work
- Short acting bronchodilators stimulate beta adrenoreceptors to increase cAMP, leading to increased Ca2+, producing bronchodilation of smooth muscle of airways
- Anticholinergics produce bronchodilation by blocking bronchoconstriction effect of vagal nerve stimulation on smooth muscle (muscarinic receptors M1-M3) e.g. ipratropium bromide
- Inhaled corticosteroids (beclomethasone) bind to cytosolic glucocorticoid receptor to reduce cytokines
- Disodium chromoglycate (mast cell stabiliser) prevents mast cells from granulating when antigen binds to specific IgE
- long acting beta 2 agonists can increase glucocorticoid receptor availability and have high selectivity for b2 adrenoreceptor in smooth muscle (pulmonary tissue)
Dental considerations for patient with asthma
- Ensure they have their bronchodilator on them
- Keep them calm, relaxed
- Ask if they’ve ever been admitted to ITU – how serious is it
- What triggers the asthma – avoid allergen
- Oral candidiasis from steroid inhaler use
- Prepare for emergency attack
4 risk factors for stroke
Diabetes, atrial fibrillation, hyperlipiaemia (high cholesterol), hypertension, obesity, smoking, family history
3 mechanisms of a stroke
Transient ischaemic attack due to ischaemic either due to occlusion of vessel due to atherosclerosis e.g. in the internal carotid artery
Thrombotic due to emboli from proximal sources e.g. in atrial fibrillation
Haemorrhagic (haemorrage in brain) - high blood pressure can lead to aneurysms –> cerebral haemorrhage
What tests would you carry out for a stroke
Cerebral CT scan
Blood scan looking for clotting factors etc.
ECG
What is a transient ischaemic attack
Interruption of
blood to the brain which resolves within 24 hours. Stroke like
symptoms.
6 symptoms of Parkinsons
Tremor Rigidity Bradykinesia Shuffling gait Loss of facial expression Weak voice Constipation
Which part of the brain does Parkinsons affect?
Degeneration of pigmented cells in substantia nigra leading to dopamine deficiency
2 ways in which Parkinsons affects dental treatment
Tremor - unable to open mouth
Unable to lie flat
4 conditions that cause tremors
Parkinsons Stroke Multiple sclerosis Hyperthyroidism Alcoholism
3 year old, feels well and spontaneously bleeds. Has high WBC, low platelets and glucose
- what is the diagnosis
- 8 clinical features of this condition
- pathology of this condition
- 2 treatments
- how does this condition affect dentistry?
- Acute lymphoblastic leukaemia
- Pallor, lethargy, infections, bleeding, bone pain, fever, swollen lymph nodes
3.Malignant proliferation of lymphoblasts in bone marrow.
Mainly affects children - Induction and consolidation chemotherapy
- Short apt times, pre-tx assessment, dental care in acute phase: identify oral disease, risk,
remove, side effects, OH, prevention; acute phase: limit to emergency care, dental tx close to next
cycle of chemo as possible; post: continue at least 12M. children seen by paedriastis (3M) and ortho every 6M
How does acyclovir work?
HSV thymidine kinase phosphorylates guanosine when HSV DNA replicates. Humans can’t phosphorylate ACV very well.
In HSV infected cells, ACV is phosphorylated by viral
Thymidine kinase to ACV-P. ACV-P then inhibits virus
replication as it is a chain terminator.
Simple terms: Acyclovir inhibits viral replication as it is
integrated into the viral DNA but does not have a terminal hydroxyl group so bases cannot be added, so it is a chain terminator.
Graves mechanism
Autoantibody binds to TSH receptor on thyroid cells and stimulates it causing increased production of T3 and T4. -more?
Dental considerations with hyper and hypothyroidism
Hyperthyroidism ● Don't use adrenaline in local anaesthetics (uncontrolled hyperthyroidism) as increased sensitivity may result in arrhythmia or palpitations ● Antithyroid drug carbimazole may cause taste disturbance ● If have AF may be on warfarin ● Goitre may compress trachea when supine of it's very big ● Accelerated dental eruption ● Maxillary and mandibular osteoporosis ● Increased susceptibility to caries ● Periodontal disease Hypothyroidism ● Susceptible to oral candidiasis ● Don't use sedation unless in a specialised unit ● Delayed eruption ● Enamel hypoplasia ● Micrognathia ● Thick lips ● Macroglossia ● Dysgeusia ● Mouth breathing ● Delayed wound healing
What tests would you do if you suspected pt had pneumonia?
Chest x-ray Sputum cytology Serology Blood tests Bronchoscopy CT Scan
Pneumonia - why does pt have pain on inspiration
Alveoli are inflamed due to pneumonia. Expansion of
inflamed tissue as air enters alveoli during inspiration
causes pain.
8 tests for TB
● Tuberculin skin test ● Chest X-ray ● Sputum smears ● Sputum culture ● Ziehl-Neelson Stain ● Auramine Rhodamine Stain ● Automated culture ● Quantiferon Gold
4 risk factors for TB
● HIV infection ● Immunosuppression e.g. steroids, chemotherapy, transplants, elderly ● Overcrowded conditions ● Malnourished ● Stay in high rate country ● Those exposed to TB in youth ● Children of parents in high rate countries ● Prisoner, drug addicts, alcoholics
6 medical conditions that cause osteoporosis
i. Hyperparathyroidism
ii. Cushing’s
iii. Kidney Failure
iv. Vitamin D deficiency
v. Hyperthyroidism - increased early osteoporosis of
Mandible and Maxilla
vi. Crohn’s Disease - malabsorption
Mechanism for bisphosphonates
i. Bisphosphonates encourage osteoclasts to undergo
apoptosis, slowing bone resorption. Also inhibits Oc recruitment and activity.
ii. It mimics pyrophosphate, giving bisphosphonates a
high affinity for bone, so it lasts for a long time (years).
Pink puffers vs blue bloateres
Pink puffers: emphysema -thin appearance -increased CO2 retention -minimal cyanosis -purse lip breathing -dyspnoea and exertional dyspnoea -barrel chest -speaks in short jerky sentences -use of accessory muscles Blue bloaters: COPD -airway flow problem -colour is dusky to cyanotic -recurrent productive cough -hypoxia and hypercapnia -respiratory acidosis -high haemoglobin -increased respiratory rate -dyspnoea on exertion -finger clubbing
What is the significance of breathing through pursed lips
Patient coping strategy to allow symptomatic improvement
Creates “auto-PEEP” to allow prolonged opening of distal airways to allow emptying of lungs
COPD antibiotics given if
2 of the following:
- increasing dyspnoea
- sputum production
- sputum purulence
Oral Prednisolone COPD
7-10 days(0.6mg/kg/day) = 30-40mg/day
More rapid improvement in physiology
Shortens hospital discharge
Must weigh severity against side effects
SABA side effects
Nervousness Increased heart rate Tremor Hypokalaemia Headache
Patient has atherosclerosis, what are the pathophysiological features of coronary
artery disease?
Initial fatty streak caused by accumulation of lipids (due to diet - hyperlipidemia and high cholesterol). Accumulation in tunica intima beneath endothelium.
ICAM-1 recruits foamy macrophages
Internal elastic lamina fragments and smooth
muscle cells migrate from the tunica media into the
lesion
Fibrolipid plaque - deposition of collagen, progressive fibrosis
PDGF stimulate fibroblast and smooth muscle cell
proliferation
Formation of complicated plaque - fibrous cap of the lesion protrudes into lumen
Beneath this are cholesterol clefts and foamy
macrophages
ohe fibrolipid plaque disturbs laminar blood flow, creating local turbulence
The currents cause endothelial ulceration where
there is collagen exposed to the blood content
This leads to activation of the coagulation cascade,
fibrin deposition and platelet aggregation
Erythrocytes become entrapped within the platelet
mesh
Fibrin forms on top of this complex in a layered
structure (platelet layer, erythrocyte + fibrin,
platelet layer etc…)
More turbulence, more platelet and fibrin deposition
Thrombus formation
Investigations type 2 diabetes
Hb1Ac (blood glucose test) Urine dipstick test Oral glucose tolerance test Fasting plasma glucose FBC
Patient has type 2 diabetes, abscess and allergic to penicillin. Gram pos cocci and gram negative bacilli – what are the organisms in the abscess
Strep viridans and fusobacterium
Testing pt with renal failure
Urine dipstick test (creatinine, urea and glucose) Blood sample - urea and electrolytes eGFR Imaging Biopsy
Systemic complications of inflammatory bowel disease
Dermatitis herpetiformis Severe dehydration > risk of colon cancer Weight loss Abdominal pain Mouth ulcer Fistula formation
MIC vs MBC test
Minimal inhibitory concentration - inoculum added to test-tubes and left overnight. The minimum concentration at which no visible growth is seen will clear the cloudiness from the test tube.
Minimal bactericidal concentration: Take the test tube from MIC and place it in an agar plate. Add inoculum until cloudiness clears from agar. This is the MBC
4 tests for CKD
Serum creatinine
eGFR
Urinary dipstick test (proteinuria, haematuria)
FBC (check for anaemia and platelet count)
Ultrasound, MRI or CT scan
Inflammatory marker test for CRP (C reactive protein) and ESR (erythrocyte sedimentation rate)
Mechanisms of antivirals
- Penetration/ uncoating
- Taking over viral machinery
- Post-translation inhibition
Samter’s triad
Aspirin sensitivity
Nasal polyps
Sinusitis
6 Ps of leg ischaemia
Pain Pallor Pulselessness Parasthesia Paralysis Perishingly cold
Tests for acromegaly
Test for IGF-1 production and levels
MRI of pituitary
ACE inhibitors mechanism
Produce vasodilation by inhibiting the formation of
angiotensin II from angiotensin I by inhibiting Angiotensin
Converting Enzyme.
● Also prevents breakdown of bradykinin, increasing its
levels which contribute to vasodilator actions.
● It also down regulates sympathetic activity by blocking the effects of adrenaline
● Blocks angiotensin II stimulation of aldosterone secretion which promotes renal excretion of sodium and water reducing blood volume and venous/atrial pressure.
Clopidogrel action
P2Y12 (sub-type of ADP receptor) inhibitor
● Which is an important ADP receptor on platelets
● Platelet not activated so no platelet aggregation and linking
to fibrin meshwork.
● Acts lifetime of platelet
Describe how an upper and lower motor weakness presents (4)
and the difference between the two (1)
UMN presents with increased muscle tone, Weakness, increased reflexes, up going plantar response.
LMN presents with decreased muscle tone, weakness, atrophy, absence of reflex
In UMN, there is bilateral innervation at level of cortex so look for forehead sparing.
4 types of lung cancer
● Small Cell carcinoma
● Non-small cell carcinoma
● Adenocarcinoma
● Squamous cell carcinoma
4 conditions with constant high glucose
● Acromegaly – excess GH
● Cushings- Excess Glucocorticosteroids
● Diabetes mellitus – insulin insufficiency
● Pheochromacytoma
Conditions that leave you immunocompromised
■ Acute myeloid leukaemia - overproduction of immature
myeloid cells (myeloblasts) in bone marrow so lack of
mature myeloid cells
■ Multiple myeloma - overproduction of B cells, but all
derived from single B cell so only 1 antibody type produced
■ Chronic myeloid leukaemia
■ Chronic lymphocytic leukaemia
■ Liver failure - doesn’t produce immune factors
■ Diabetes - affects white cell chemotaxis and complements
■ Renal failure - splenomegaly - reduced circulating volume
of white blood cells - more in the spleen
Action of prasugrel
Blocks ADP receptor irreversibly (acts for lifetime of platelet i.e. 7-10 days)
What is thrombolysis?
Streptokinase or alteplase activate plasminogen –> plasmin. This lyses clots by breaking down fibrinogen and fibrin
Symptoms, treatment of primary polycythaemia (rubra vera) and what it can lead to
- pruritis, red face, thrombosis, splenomegaly, hepatomegaly
- venesection, aspirin, myelosuppression
- myelofibrosis (15-20%), acute myeloid leukaemia (2-10%)
Hep C treatment
Interferon alpha and ribavirin
Essential thrombocythaemia treatment
Aspirin, hydroxycarbamide, interferon, anagrelide
Chronic myeloid leukaemia treatment
Imatinib (Glivec) blocks abnormal tyrosine kinase activity, can result in molecular remission
Allogeneic stem cell transplantation
D-dimer test
For pulmonary embolism
Wherever there is clotting/injury, there is likely to be D-dimer released
D-dimer test is SENSITIVE (negative test leaves about 1% chance of PE), but
test is not SPECIFIC
Also elevated in:
-Liver disease (alcoholics, dehydration, co-smoking
with alcoholism)
-Inflammation – esp pneumonia (will be short of
breath too!)
-Pregnancy (predisposed to DVT and PE too and also
risks of CTPA)
-Malignancy (predisposes to DVT and PE)
-Trauma (but immobilisation may have caused a DVT
and PE)
SADCASE
Suicidal Anxiety, addiction Depression, disordered thoughts, delusion Concentration loss Auditory, visual disturbances Sleeping difficulties Eating habits
SADCASE
Suicidal Anxiety, addiction Depression, disordered thoughts, delusion Concentration loss Auditory, visual disturbances Sleeping difficulties Eating habits
2 types of diuretics used to treat hypertension
Thiazide diuretics – inhibit reabsorption of sodium and chloride in cortical diluting segment of ascending loop of henle
Loop diuretics – inhibit reabsorption of potassium, sodium and chloride in thick segment of ascending loop of henle. Also increase production of prostaglandins which results in vasodilation.
This results in decreased reabsorption of water into blood so there’s less blood volume and reduced pressure
Summarise how kidney failure affects the metabolism of calcium in the body
Less Ca reabsorption in tubules which means less Ca in the blood
In CKD the kidneys have a lesser response to PTH so less calcitriol secreted therefore less calcium reabsorption by the intestine
Because of reduced blood calcium, the parathyroid gland compensates for this by increasing production of PTH. PTH causes calcium to be released from bone into blood.
Treatments for asthma
Emollients
Topical Steroids
Antihistamine for itch
Antibiotics if infected
Explain how penicillin works.
Beta lactam – contains B lactam ring & inhibits cell wall formation
Inhibit cross linking of peptide chains
There are lots of proteins called penicillin binding proteins (PBP’s) on
bacteria which have affinity for penicillin. Transpeptidase is involved
in crosslinking.
Other PBP’s involved in maintenance of cell wall.
Penicillin activates autolysin inhibitors so bacteria produce autolysin
which produce defects in cell wall
MC CHESS
● Enzymes
o Hyalurondinase for spreading
o Streptokinase breaks down clots
o C5a peptidase reduces chemotaxis by reducing infiltration of neutrophils
● Toxins
o Streptolysin O and S – binds cholesterol
o Erythrogenic toxin – exaggerated response (rash)
● Surface factors
o Capsule – hyaluronic acid
o M protein – encourages complement degradation
5 similarities or differences between gram positive and gram negative cell membrane structure
● Gram+ve has no outer cell membrane
● Gram+ve has thick peptidoglycan cell wall
● Gram+ve retains crystal violet stain
● Gram+ve low lipid content
● Gram+ve no hydrophillic channels
● Gram+ve cell wall smooth, in Gram-ve it’s wavy
5 similarities or differences between gram positive and gram negative cell membrane structure
● Gram+ve has no outer cell membrane
● Gram+ve has thick peptidoglycan cell wall
● Gram+ve retains crystal violet stain
● Gram+ve low lipid content
● Gram+ve no hydrophillic channels
● Gram+ve cell wall smooth, in Gram-ve it’s wavy
3 serious complications as a result of IBS
● Bowel Cancer
● Osteoporosis as a result of steroid use
● Poor growth and development
● Primary sclerosing cholangitis
Faster tests than gram staining to diagnose TB
MGIT - autoantibodies using PCR
Organism that only grows on BCYE medium, poorly gram negative
Legionella pneumophila
Cause of atypical pneumonia
Walking case of pneumonia, develops after 2 weeks of flu-like illness, yellow phlegm, CXR patchy bilateral consolidation. What organism?
-how is it identified
Mycoplasma penumoniae
-serology and PCR (culturing is difficult)
Yersinia pestis virulence factors and treatment
Lipopolysaccharide
Type III secretion needle for injection of toxins
pCP1 - degrades complement components
pMT1 - anti-phagocytic capsule
Treatment: streptomysin, tetracycline, formalin killed vaccine
Diagnosis of UTIs: steps
Sampling of midstream Urine (with care) -cloudy or clear -haematuria? (urine might be pink) -culture on agar plates > 2x105 cells/ml -traces of protein, leukocytes >10/ml - > nitrites (NO3- > NO2-) Pure or mixed growth? Gram Stain of isolated bacteria or direct staining from urine sample
Herpetic gingivostomatitis clinical features
Incubation 3-10 days Duration 5-14 days Multiple vesicles rupture to form extensive sloughing ulcers Malaise, pyrexia, lymphadenopathy Gingivitis with erythema and sloughing
Diseases associated with chlamydia
Proctitis (homosexual men)
Reiter’s syndrome: reactive arthritis (mainly men)
Neonates infected –> conjunctivitis and/ or pneumonia in 20%
Infection and replication of herpes virus
Virus with glycoproteins sticking out –> stick to receptor on cell surface –> when they bind virus decouples and injects DNA into cell –> dsDNA uncoated, makes its way into nucleus –> co-opts host cell polymerase and DNA starts to transcribe viral genes –> translation –> makes viral proteins including viral factor which goes back to host cell polymerase –> this drives more viral DNA replication –> all bits get put together in nucleus –> viral DNA back into virus –> mature virus –> break out of nucleus –> cells get packed full, cell pops, spread to other cells around or further
Can make proteins out of very little DNA
Reversal of opioid effects
Naloxone 400mg IV
- dramatic reversal of Mu receptor opioid effects
- less effective on synthetic substances (effects on CNS less well defined)
4 associations with atrial fibrilation
Stroke Heart failure Mural thrombosis Valve disease Tachycardia-induced cardiomyopathy
How does chronic atherosclerotic plaque lead to MI
Fat pigs tell Emma and Michael monge two -fatty streak -fibrous plaque enlargement -turbulence (blood pressure increases) -endothelium ruptures and collagen exposed -activation and aggregation of platelets -meshwork of fibrin and red blood cells adhere -more turbulence and growth of plaque -thrombosis formation Blocks cardiac artery --> ischaemia
Unilateral tonsillar swelling, neck lymph nodes palpable. What 3 diagnoses would
you consider? (6)
● Lymphoma ● Carotid body tumour ● Lymphadenitis ● Lipoma ● TB ● Branchial cleft cyst ● Salivary gland/ thyroid gland tumour ● Regional metastasis ● Reactive lymph node ● Tonsilitus Peritonsillar abscess?
6 macroscopic features of lobular pneumonia
● Lung is grey/brown in colour. ● Heavy firm. ● Dilated. ● Some red seen due to blood in lungs ● Inflammation of lung ● Alveoli are fluid filled
4 investigations to ascertain your diagnosis of pneumonia
Bronchoscopy Chest x-ray CT scan Serology Sputum cytology Blood tests
Features of asthma
● Narrowing of airway ● Increased mucus (hypersecretion and plugging) ● Tightened bands of smooth muscle ● Thickened smooth muscle ● Increased vascular permeability ● Submucosal oedema ● Degran of mast cell- histamine ● Interleukin 4 increase
5 symptoms of peptic ulcer
● Abdominal pain ● Bloating and abdominal features ● Waterbrash ● Nausea and vomiting ● Loss of appetite and weight loss ● Haematemesis (vomiting blood) ● Melena (blood in faeces giving it a black tarry appearance)
How H. pylori survives in the stomach
● Motile bacteria can swim around
● Lives in mucin layer of stomach
● Produces urease – covers uric acid to ammonia and carbon dioxide
● Carbon dioxide produced protective cloud around bacterium with pH of 7
Can multiply as initially causes asymptomatic gastritis
Attracts neutrophil polymorphs
Neurological consequences of ankylosing spondylitis
● Spinal cord compression
● Lead to lower limb problems and abnormal gait, as well as bladder and bowel
disturbance.
How to measure if kidney function is safe before giving LA/ GA
● eGFR
● Urine Dipstick Testing
● Imaging – Xrays, CT, MRI
Action of calcitonin
Opposes action of PTH
Released from thyroid
Contraindications of metronidazole
Pregnancy
Alcoholics
Wafarinised pts
Hepatic impairment
Bulls eye rash
Lyme disease!
Treatment of actinomycosis
Surgical drainage
6-8 weeks broad spectrum amoxicillin to penetrate fibrotic capsule
-or penicillin or tetracycline
Benzodiazepines mechanism of action
Barbiturates / benzodiazepines –> bind to GABAa receptor at different allosteric sites –> facilitates GABA action –> Barbiturates > duration and frequency, benzodiazepines > frequency of opening of Cl- channel –> membrane hyperpolarisation –> CNS depression
At higher dose barbiturates can act as GABA mimetic
Action of glucocorticoids
E.g. prednisolone
Reduces generation of eicosanoids and PAF
-lipocortin inhibits phospholipase A2
Reduces production and action of cytokines (IL-2, IL-6, TNFα), histamine and complement
–> reduced bronchoconstriction and airway inflammation
Action of PPIs
Act by irreversibly blocking H+/ K+ ATPase (gastric proton pump)
Used for prolonged and long lasting inhibition of gastric acid
Leprosy treatment
Dapsone and rifampicin NOT thalidomide
Lytic life cycle
PLARM viruses Attach Penetrate Replicate Mature Lysis
Diphtheria symptoms
Thick dirty white/ grey/ green/ black coating 'Bull Neck' Sore throat Fever Lymphadenopathy
Use of flow cytometry in HIV
HIV infects CD4 T cells (T helper cells)
The number of CD4 T cells compared to CD8 T cells is determined
using Flow Cytometry
In HIV patients the number of CD4 cells is important as low CD4
numbers can mean progression to AIDS
Conjugation of TI antigens to proteins
Hib polysacc specific B cells bind polysaccharide and internalise whole conjugate, including protein Polysaccharide cannot be processed, but protein is and peptides derived from it are expressed on cell-surface with MHC class II Polysaccharide specific B cell receives help from DT specific T cell Strong antibody response even in infants, including IgG
Live attenuated vaccine examples
Only 2
BCG- Bacille Calmette Guerin. Mycobacterium bovis grown over many passages in vitro. Gives some protection against TB
Salmonella typhi- temperature sensitive strain given orally.
Recombinant protein vaccine examples
•2 examples on market, Hep B surface antigen, and HPV vaccines Cervarix and Gardasil
Therapeutic Ab steps
Therapeutic Ab taken into cell via endocytosis
It enters the lysosome where the proteolytic
enzymes and pH release the drug inside the cell
The drug gets transported to the nucleus where it affects cell division.
Other cytotoxic molecules can be used to kill cells directly
Viral live attenuated vaccines examples
Poliomyelitis (Sabin)-widely used to bring polio to the brink of eradication
Vaccinia virus- used in billions of doses to eradicate smallpox due to cross-reactivity between itself and the variola virus
Measles, mumps and Rubella- 3 given together
Viral whole killed vaccine examples
Polio vaccine (Salk)-inactivated virus-IPV
Influenza vaccine-inactivated virus
Hepatitis A vaccine-inactivated virus
Rabies vaccine-inactivated virus
Bacteria non-living vaccines examples
Diphtheria-cell free formaldehyde treated toxin- rendered non toxic “toxoid”
Tetanus, toxoid, as above
Pertussis- killed whole bacteria, given with the two above as DTP. 3-doses. UK now moved to acellular pertussis (aP)
Cholera- heat killed bacteria
Histamine release –>
Vascular dilation ↑ Vascular permeability i.e. oedema Bronchospasm Urticarial rash – nettle rash ↑ nasal and lacrimal secretions
HyperIgM immunodeficiency mechanism
CD40 important for ‘class switching’ Where IgM turns to IgG (Ab has same specificity) So can not switch from IgM to IgG Susceptible to pyogenic infections & autoimmune disease (form auto‐IgM antibodies to neutrophils & platelets)
X-linked agglobulinaemia mechanism
Defective btk gene that encodes a B cell tyrosine kinase
btk Important in maturation of B cells
No B cell maturation SO no IgG – poor Ab responses
First 6‐12 months of life have protective maternal IgG
Get recurrent pyogenic infections
IgA deficiency
Most common immunodeficiency (1 in 700 Caucasians)
Failure in terminal differentiation of B cells to plasma cells
Individuals develop Type III hypersensitivity (immune complex)
Susceptible to pyogenic infections
Passive immunisation: specific immunoglobulin examples
Human tetanus immunoglobulin (HTIG)
-rapid protection of exposed individuals
Human rabies specific Ig
-used after exposure to rabies to give protection until vaccine becomes effective
Human Hepatitis B Ig (HBIG)
Varicella Zoster Ig (VZIG)
LAD type 1
Deficient for CD18 (integrinβ chain)
Defective C’ Receptor 3 (CD18/CD11b) - this binds bacteria
opsonised with C3bi – increase phagocytosis
Can not phagocytose opsonised bacteria – recurrent infections
ALSO
Defective CD18/CD11c
Important in leukocyte adhesion (CD18/CD11c binds to ICAM‐1)
Phagocytes not able to bind to the endothelium and
extravasate
Chronic granulomatous disease
Defective NAPDH oxidase
Phagocytes CANNOT form superoxide ions & H2O2 (ROS ‐ Reactive
Oxygen Species) to kill microbes
Organisms remain alive in phagocytes – persistent intracellular infections &
granulomas form
Infections with S. Pneumoniae &
abbesses in liver, skin etc.
Glucocorticoids and immunodeficiency
Repeat dose – leads to low lymphocytes, lack of Ab and defective cytokine synthesis
Secondary immunodeficiency - drugs - anti-cancer therapy - chemotherapy - Azathriopine
Azathioprine is converted to 6‐mercaptopurine in body then
metabolised to thioinosinic acid (a false base – chain terminator)
-this gets incorporated into DNA & stops DNA replication and proliferation
Diagnosis of Chronic granulomatous disease
Inability of phagocytes to reduce nitroblue tetrazoliium (NBT) dye
NBT is pale yellow when taken up by phagocytes during phagocytosis.
In healthy phagocytes it is reduced by ROS to a purple colour
In pxs with CGD the dye remains yellow
Hereditary angioneurotic oedema
Most important C’ deficiency
C1 inhibitor‐ inhibits activation of C1 ( first initiator of C’
pathway)
Inhibits C’ and elements of the kinin/clotting system
Allows severe oedema due to plasma leakage leakage
Patients have recurrent swelling
Intestine - abdominal pains and vomiting
Upper airways - choke and death due to obstruction
5-FU mechanism
Pyrimidine analog that works through inhibition of thymidylate synthase
(this methylates deoxyuridine monophosphate (dUMP) into thymidine
monophosphate (dTMP))
SO – 5FU blocks thymidine synthesis, which is a nucleotide required for
DNA replication
5FU gets incorporated into DNA and RNA and induces cell cycle arrest
(in S‐phase) and apoptosis
Affects T and B cells & NK cell numbers
X-linked agglobulinaemia treatment
Repeated injections of gamma-globulin throughout life
Organ transplantation - T cell Ag recognition and activation
Involves co‐stimulatory molecules
CD28 on T cell bind to CD80/ CD86 on APC
This is required for full activation
Activation: IL-2 secreted and bind to IL-2R on T cells
Leads to: division, differentiation, effector functions, memory
What type of patients are NSAIDs contraindicated in (6 marks)
- Past Myocardial infarct patient (excluding Aspirin)
- Peptic ulcer or stomach bleeding
- Uncontrolled hypertension
- Kidney disease
- Past transient ischaemic attack
- Past stoke (excluding Aspirin)
- Coronary Artery Disease (excluding Aspirin)
- Third trimester for Pregnancy
Bone regeneration after a fracture (6 marks)
• Inflammation
Haematoma forms. Dead bone cells release cytokines which initiate healing process.
Osteoclasts recruited to remove dead bone cells. Blood clot joins two fractured prices of
bone, fibroblasts begin to lay down granulation tissue over the clot
• Soft callus formation
Fibroblasts now start to lay down cartilage and fibrocartilage. Blood vessels begin to form
Then osteoblasts from periosteum begin to lay down woven bone (soft and disorganised)
• Hard callus formation
Calcium and phosphate incorporated into the cartilage => hard callus
• Bone remodelling stage
Woven bone replaced by cortical and trabecular bone
Blood test results and diagnosis. Increased levels of white blood cells and decreased platelets and
hb, what is diagnosis? (2 marks)
• Acute Myeloid Leukaemia
• Malignant Proliferation of myeoloblasts in bone marrow -> go on to make basophils,
eosinophil’s, neutrophils, macrophages
Signs and symptoms of acute myeloid leukaemia
- Anaemia (fatigue, paleness, and shortness of breath)
- Neutropenia (liability to infections)
- Thrombocytopenia (easily bleeding and bruising - purpura)
- Lymphadenopathy (rare but common in ALL)
- Bone Pain
- Hepatosplenomegaly – asymptomatic
- Oral Ulcers
- Gum infiltration by leukemic cells in Acute Monocytic Subtype M5
Pathology of Parkinsons disease
• Degenerative disorder of the central nervous system
• Degeneration of pigmented cells of the ventral aspect of Pars Compacta of substantia nigra
leading to dopamine deficiency
• Disease may also result previous brain history or cerebrovascular disease
Treatment for graves. 3 answers
- Carbimazole
- Partial thyroidectomy
- Radioactive iodine
Dental implications of a patient that has over or underactive thyroid and how its relevant (6 marks)
Hyperthyroidism o Don't use adrenaline in local anaesthetics (uncontrolled hyperthyroidism) as increased sensitivity may result in arrhythmia or palpitations o Antithyroid drug carbimazole may cause taste disturbance o If have AF may be on warfarin o Goitre may compress trachea when suppine of it's very big o Accelerated dental eruption o Maxillary and mandibular osteoporosis o Increased susceptibility to caries o Periodontal disease Hypothyroidism o Susceptible to oral candidiasis o Don't use sedation unless in a specialised unit o Delayed eruption o Enamel hypoplasia o Micrognathia o Thick lips o Macroglossia o Dysgeusia o Mouth breathing o Delayed wound healing
Investigations for pneumonia
- Chest XRay
- Urinary antigen test
- Sputum culture
Posterior circulation stroke syndrome
• Supplied by vertebra-basilar system
• Includes cerebellum, brain-stem cranial nerve nuclei
• Symptoms; incoordination of movement, visual field loss, hemiparesis (weakening of entire
side of body)
Transient ischaemic stroke
• Stenosis/narrowing or occlusion of carotid artery – completely reverses within 24hours
• (Stroke if more than 24 hours)
• Causes hypoxia of brain tissue
• Symptoms Weakness or clumsiness of a hand, arm, or leg. Difficulties with speech.
Difficulties with swallowing. Numbness or pins and needles of a part of the body. Brief loss
of vision, or double vision.
Investigations for stroke
- Blood tests (thyroid function, cholesterol, glucose)
- Carotid Duplex (ultrasound of major arteries in neck)
- CT scan (rule out possible bleed)
- ECHO (ultrasound scan of heart)
- MRI scan to further investigate CT
Investigations for biliary colic
- Ultrasound of right upper quadrant
- Endoscopic retrograde cholangiopancreatography
- CT
- MRI
Investigations for TB
- Chest xray
- Sputum smear
- Automated culture (MGIT)
- Nucleic acid detection tests
- Tuberculin test (Heaf, Tine and Mantoux – protein derivatives of TB injected subdermally)
- Blood test – detect reactive T cells
Mycobacterium TB. Give the information about the organism (6 marks)
• Rod shaped organism
• Facultative intracellular pathogen
• Obligate aerobe – needs a lot of O2 to grow
• Cell wall rich in lipids (mycolic acid) – so doesn’t retain gram stain (although technically
gram+)
• Divides very slowly (15-20h)
• Stained with acid fast ziel-Nielsen stain
Factors that predispose to TB
- Immunocompromised
- Unhealthy over-crowded conditions
- Staying in high rate country (and children of parents from high country)
- If exposed to TB while in youth
- Prisoners, drug addicts, alcoholics
- Malnourished
How does secondary TB work?
Caseous (cheese-like) centres of tubercles liquefy
Organisms grow very rapidly in this
Large Ag load
-bronchi walls become necrotic and rupture
-cavity formation
-organisms spill into airways and spread to other areas of lung - highly infectious
Primary lesions heal - Ghon complex, Simon foci
How does AF cause stroke
- Blood pools in atria
- Blood clot forms
- Blood clot breaks off
- Blood clot travels to brain and blocks a cerebral artery causing a stroke
Clopidogrel action
Irreversible ADP mediated platelet inhibition.
Action of nitrates
Symptomatic relief of angina
Produce nitric oxide at endothelial surface leading to vascular smooth muscle relaxation and arteriolar and venous dilatation
< myocardial oxygen demand (lower preload and afterload) and increase myocardial oxygen supply (coronary vasodilatation)
Statins mechanism
Hydroxymethyl-glutaryl (HMG) CoA reductase inhibitors
Lower LDL cholesterol and may increase HDL cholesterol
< risks of MI stroke and CV death
Systems effects of infective endocarditis
Splinter haemorrhage in nailbed (NOT leukonychia)
Osler’s nodes (red lesions on hands and feet)
Embolic infarct in kidney
Embolic infarct in spleen
Infective endocarditis leads to
Cerebral abscesses Aortic and mitral vegetations -lumps on valves caused by emboli Retinal emboli (Roth spots) Digital emboli -same cause as splinter haemorrhages, Janeway lesions etc. -not that common
Psoriasis aetiology
HLA association
T-cell mediated
Keratinocyte proliferation early
Gram stain process
Fixation –> crystal violet stain –> iodine treatment –> decolourisation –> counter stain (safranin)
Sterile sites of the body
Blood, CSF, peritoneal fluid, bone, pleural fluid, peritoneal fluid, pericardial fluid, joint fluid
Gram negative anaerobes and what they cause
Bacteroides (abdominal wound infections, necrobacillosis)
Prevotella (genital and oral infections)
-e.g. P. melaninogenica
Porphyromonas (oral infections)
Fusobacterium (oral infections and necrobacillosis)
CLED medium
Cysteine Lactose Electrolyte Deficient
Allows growth of all urinary pathogens
Lactose fermenters e.g. E.coli shown as yellow with halo around
Non-lactose fermenters show up as blue-green
Electrolyte deficient to prevent swarming of Proteus species.
Quantitative urine culture
5 microlitres loop used from urine sample
Spread over half of CLED medium and left overnight at 37 degrees
1 colony - 200 organisms/ ml
10 colonies - 10^3 organisms/ ml
100 colonies - 10^4 organisms/ ml
1000 colonies - 10^5 organisms/ml
Urinary dipstick test
Protein in the urine may indicate kidney disease (60s)
Glucose in the urine may indicate diabetes (30s)
Virulence of S. saprophyticus
A haemolysin
Adherence to uroepithelial cells by surface-associated protein
Production of extracellular slime
Haemogglutinin binds to fibronectin
Virulence of UPEC
Type 1 pili binds to mannose on glycoproteins of uroepithelium
P. fimbriae binds to gal-gal residues on ceramide host lipids
Proteus virulence
Fimbriae - adhesion
Production of urease which breaks down to urea and CO2 causing rise in pH of the bladder (can lead to precipitations and stones)
Flagella - motility
Bacteria that can cause food poisoning
Clostridium perfringens (gram positive anaerobic bacillus)
E.coli (gram negative facultatively anaerobic bacillus)
Bacillus cereus (gram negative aerobic bacillus)
Campylobacter jejuni (gram negative microaerophile which is comma shaped)
Salmonella enterica (gram negative facultatively anaerobic bacillus)
Shigella (gram-negative facultatively aerobic non-motile bacillus)
Vibrio cholerae (gram negative facultatively anaerobic motile comma shaped)
Osteogenesis imperfecta
Mutation of bone matrix mineralisation
Type I collagen mutation
Affects ears, eyes (blue sclera), skin (hyperextensible skin), teeth
Achondroplasia
Mutation of cartilage matrix formation
Autosomal dominant: mutation of FGF receptor 3 so it is constantly activated (it is a negative regulator of bone growth)
Failure of cartilage maturation at growth plate
Kyphosis
Dowager’s hump seen in osteoporosis
chalk stick fractures seen in
Paget’s disease
Genetic
Also causes hypercementosis of teeth
Osteomyelitis
Blood borne A complication of compound fractures = Necrosis of bone fragments New bone formation Sinus drains pus
47 years old woman. 20 year history of rheumatoid. Has oral discomfort and mild dysphagia.
Also has an ulcer. Takes methotrexate and folic acid. SERN positive. Prednisolone daily
(steroid)
a. 3 diagnosis for oral symptoms (3marks)
a. Medication related (methotrexate and taking steroids); secondary Sjogrens; infection (herpes/ HIV)
Behcets disease and pathergy
Blood vessel inflammation throughout body
Hypersensitive skin leads to blisters after injections (pathergy)
Mouth and genital ulcers
Erythema nodosum
Iritis
Headaches/ migraines
Folliculutis
Conditions that present with mouth ulcers
Crohns/ ulcerative colitis/ inflammatory bowel syndrome Behcets Herpes Systemic lupus erythematous Aphthous ulcer Corticosteroid induced HIV infection Coeliac Ankylosing spondylitis
What are rheumatoid nodules
Collections of inflammatory cells under skin, will mean the patient will test positive for rheumatoid factor.
Roth’s spots
Infective endocarditis
28 year old nurse. Fatigue. Joint pain. Sandy eyes. Mild dysphagia and ANA positive
a. Diagnosis?
b. Tests?
c. Risks
Primary Sjogrens b/ Schrimers test Rose Bengal stain Sialometry Sialography Ultrasound Biopsy of labial gland (inner lip) c. Weight loss Fever Malaise Lymphoma risk
Rheumatological conditions linked with antinuclear antibodies
Primary Sjogrens
Polymositis
Scleroderma
Systemic lupus erythematous
Which virus infects E. Coli
Enterobacteriaphage T4
Verotoxin affects
Kidney in haemolytic-uraemic syndrome
CD4/ CD8 levels in HIV
In normal people it is around 2 (between 1 and 4)
If it is less than 1 you may have HIV or AIDS
Uraemia symptoms
Nausea. Vomiting. Fatigue. Anorexia. Weight loss. Muscle cramps. Pruritus. Mental status changes. NOT bruising
Tricyclic antidepressants side effects
blurred vision, dry mouth, constipation, weight gain or loss, low blood pressure on standing, rash, hives, and. increased heart rate.
Pt has had TB for a month and been on treatment since then, how should you treat them in the dental surgery?
Not infectious - normal cross infection control
MS symptoms
fatigue vision problems numbness and tingling (including loss of sensation on face) muscle spasms, stiffness and weakness mobility problems pain problems with thinking, learning and planning depression and anxiety sexual problems bladder problems bowel problems speech and swallowing difficulties
Drugs contraindicated in pregnancy
Metronidazole <28 weeks, tetracycline, augmentin, avoid ketoconazole, miconazole , amphotericin , NSAIDs >34 weeks
Drugs that increase INR
CYP450 inhibitors: Erythromycin Grapefruit juice Omeprazole Ketoconazole Diltiazem Verapimil Amiodarone Isoniazid ALSO
What disease are patients undergoing dialysis at risk of?
K related arrhythmias - cardiovascular disease
Photophobia and severe headache cause
Migraine
Meningitis
Acute (angle closure) glaucoma
Unconscious hypoglycaemia treatment
1mg IM Glucagon/IV glucose 100ml dextrose 10%/Dextrose 30-50ml 50%
Zoplicone
Sleeping pill for SHORT TERM USE only
Contraindicated in psychiatric illness
Signs and symptoms of hypoglycaemia
- Symptoms: Anxiety, palpitations, dry mouth, hunger, sweating, tremor (increased adrenaline response)
- Signs: Confusion, slurred speech, aggression, coma, convulsions, death (neurological response)
Vitamin A deficiency
Night blindness
Treatment for giant cell arteritis
Steroid, usually prednisolone
Causes of vertebral wedge (compression) fracture
Osteoporosis
-can be caused by steroid medications e.g. osteoporosis
Normocytic anaemia
A normocytic anemia is defined as an anemia with a mean corpuscular volume (MCV) of 80–100 which is the normal range. However, the hematocrit and hemoglobin is decreased.
M&W >85yo
Blood loss is a common cause
Diabetes insipidus
Lack of production of vasopressin (ADH) produced by posterior pituitary or impaired response to ADH by the kidney
Thirst and polyuria
Causes: head injury, pituitary tumour or sarcoid
SIADH
Syndrome of inappropriate ADH secretion
Low blood sodium level with high urinary sodium concentrate
Secondary to some malignancies and certain benign chest disorders e.g. pneumonia.
Phaeochromocytoma
Rare cause of hypertension
Benign tumour of adrenal medulla producing excess catecholamines e.g. adrenaline
Symptoms: headaches, sweating, palpitations, pallor, hypertension
Usually unilateral
Anaesthetic injections with Adr should be avoided
Depression and dentsitry
Hypochondriachal ideas and delusions
May worsen pre-existing dental anxiety
Appetite reduced –> may ascribe this as ‘teeth being too weak’
Alcohol excess may be cause or consequence
Oral hygiene may deteriorate (self-neglect)
Streptokinase and alteplase mechanism
Plasminogen activator –> plasmin
HBsAg
Hepatitis B surface antigen - first manifestation of infection
Hep B core antigen: HBcAg
-if HbSAg -ve but HbcAg +ve it signifies donor infectivity
Hep B e antigen: found if HBsAg +ve (index of infectivity)
Ab to HbsAg: protection from infection
Sarcoidosis
Sarcoidosis is a disease involving abnormal collections of inflammatory cells that form lumps known as granulomas. The disease usually begins in the lungs, skin, or lymph nodes. Symptoms: -respiratory impairment -visual impairment -jaundice -renal impairment -steroid therapy -Associated with Sjogrens -gingival enlargement -cranial neuropathies
CTFR gene
Cystic fibrosis
Ankylosing spondylitis symptoms
HLAB27 gene Back pain and stiffness Arthritis Enthesitis Fatigue Anterior uveitis
Conns syndrome
Hyperaldosteronism is a disease in which the adrenal gland(s) make too much aldosterone which leads to hypertension (high blood pressure) and low blood potassium levels
- increased sodium
- increased glucose
Oesophageal cancer survival rate
20% 15-39s
5% 80-99s
Causes of finger clubbing
GI -liver cirrhosis -inflammatory bowel disease Cardiothoracic -infective endocarditis -cyanotic congenital heart disease -intrathoracic pus e.g. lung abscess, bronchiectasis -bronchial carcinoma -fibrosing alveolitis Other -familial -idiopathic -secondary to thyrotoxicosis
Abdominal aortic aneurysm
Localised enlargement of abdominal aorta such that the diameter is >3cm or 50% larger than normal diameter.
Usually asymptomatic but may present with abdominal, leg or back pain
Rupture is usually fatal
Vitamin B12 deficiency associated with
Folate deficiency / macrocytic/ megalolastic anaemia
- caused when red blood cells aren’t produced properly
- because cells are too large, they may not be able to exit bone marrow to enter bloodstream and deliver oxygen
Glucocorticoid cover
Major surgery/ GA: hycdrocortisone 100mg IM at induction and double oral med 24hr
Simple procedures: double dose 1 hr before, double oral med 24hr afterwards
Most frequent complication of Paget’s disease
Bilateral progressive hearing loss (sensorineural)
Reversal drug for heparin
Protamine sulphate
What drug should not be given to pregnant woman with rheumatoid arthritis
Methotrexate
Testing for H. influenzae
Chocolate agar
Gram stain
Catalase and oxidase positive
Latex agglutination test
Sympathetic cervical chain dysfunction
Horner’s syndrome
Familial dysnautonomia
Which genetic condition most likely to cause DVT
Antithrombin deficiency
-last likely Prothrombin deficiency and P20210A mutation
How long do symptoms last in
- salmonella
- shigella
- campylobacter
- cholera
Salmonella 4-7 days
Shigella (dysentery) around a week
Campylobacter up to 2 weeks
Cholera rice water stool - must be treated quickly
Trigeminal neuralgia treatment
Antiepileptic/ anticonvulsant
Iron deficiency can cause
Microcytic anaemia
Macrolides and mechanism
Erythromycin, azithromycin, clarithromycin
Interferes with protein synthesis by binding to 50s subunit of bacterial ribosome
Aminoglycosides and mechanism
Interfere with reading of codes on the ribosome
Gentamycin
Curb 65
for predicting mortality in community-acquired pneumonia and infection of any site
Mydriasis
Dilation of pupil of eye
Complications of sickle cell disease
Brain: Stroke
Eye: Proliferative retinopathy, retinal artery occlusion, retinal detachment
Spleen: autosplenectomy
Liver: Gallstones
Urinary: Priapism, renal papillary necrosis
Locomotor: Avascular necrosis of the hip
Skin: Leg ulcers
Psychosocial: Depression
SLE hypersensitivity type
Type III
Which valve of the heart is most likely to get infected with infective endocarditis in IV
drug users
Tricuspid
Alveoli size
An adult alveolus has an average diameter of 200 µm
