Human diseases 2 Flashcards
Name four types of malabsorption/small bowel disease
1) pernicious anaemia
2) coeliac disease
3) crohn’s disease
4) small bowel infections
Name two types of large bowel disease
inflammatory bowel disease (IBS) - Crohn’s and ulcerative colitis
Colonic cancer
What medication used in upper GI disease eliminates formed acids?
Antacids
How do antacids work?
alkalis that form a salt with gastric acid and neutralise the effects on the tissues e.g. gaviscon, Rennies
What medications used in upper GI disease reduce acid secretion?
H2 receptor blockers
proton pump inhibitors
What are the three main triggers for stomach acid production?
acetylcholine
gastrin
histamine
What are stomach acids produced by?
parietal cells in the stomach wall
How do H2 receptor antagonists work?
reduce acid production by preventing histamine activation of acid production
Why are H2 receptor antagonists not as effective as proton pump inhibitors?
limited effect as they only interrupt histamine pathway, gastrin and acetylcholine still active whereas PPIs block acid production whether there is a trigger or not
Name two H2 receptor antagonists
cimetidine
ranitidine - available over the counter
Name three proton pump inhibitors
omeprazole, lanzoprazole, pantoprazole
Which medications end in -prazole?
Proton pump inhibitors
anti-ulcer drugs that reduce gastric acid production.
What are proton pump inhibitors used for?
profound and prolonged reduction of stomach acid production
What is dysphagia?
difficulty swallowing
What are the three main causes of gastro-oesophageal reflux disease?
defective lower oesophageal sphincter
impaired lower clearing (oesophagus not emptied properly)
impaired gastric emptying (stomach full so contents re-enter oesophagus)
What are the effects of GORD?
Ulceration, inflammation, metaplasia (gastric)
Barrett’s oesophagitis - precancerous adenocarcinoma
What is Barrett’s oesophagitis?
lining of the oesophagus damaged by acid reflux, which causes the lining to thicken and become red
What are the signs and symptoms of GORD?
epigastric burning - worse lying down, bending, pregnancy
dysphagia
GI bleeding
severe pain - mimics MI, oesophageal muscle spasm
What is a hiatus hernia?
when part of the stomach squeezes up into the chest through an opening (“hiatus”) in the diaphragm
How is GORD managed?
smoking cessation (improves sphincter)
weightloss
antacids
H2 blockers and PPIs - ranitidine and omeprazole
Where does peptic ulcer disease occur?
any acid affected site
oesophagus, stomach, duodenum
What can cause peptic ulcer disease?
normal acid secretion - stomach
high acid secretion - duodenal
drugs - NSAIDs, steroids
What bacterium causes peptic ulcer disease?
helicobacter pylori
How does helicobacter pylori cause peptic ulcer disease?
infects lower part of stomach (antrum), causes loss of mucous barrier and allows stomach acid to cause ulceration to stomach lining
What are the effects of peptic ulcer disease?
gastric ulcers
chronic gastric wall inflammation
mucosa assoc lymphoid tumour (MALT)
How is peptic ulcer disease managed?
Triple therapy
2 antibiotics, 1 proton pump inhibitor
What are the signs and symptoms of peptic ulcer disease?
asymptomatic
epigastric burning pain - worse at night, before/after meals, relieved by food, alkali and vomiting
usually NO physical signs unless complications
How is peptic ulcer disease investigated?
endoscopy
radiology - barium meal
anaemia - FBC and faecal occult tests
Helicobacter pylori - breath, antibodies, mucosa
What are the possible complications of peptic ulcer disease? local and systemic
local - perforation, haemorrhage, stricture, malignancy
systemic - anaemia
What does coffee ground vomit indicate?
large peptic ulcer bleed
How can you improve the mucosal barrier in upper GI disease?
eliminate helicobacter pylori
inhibit prostaglandin removal - so reduce/avoid NSAIDs and steroids
What medications are used in triple therapy for peptic ulcer disease?
2 antibiotics - amoxycillin, metronidazole
1 proton pump inhibitor - omeprazole
Describe the three surgeries that can be used in management of PUD
1) Bilroth 1 - part of stomach removed and duodenum reattached to top half of stomach
2) Bilroth 2 - part of stomach removed and top half reattached to small bowel and duodenum sewn up
3) highly selective vagotomy - dividing vagus nerve supply to stomach to reduce neurological trigger for acid secretion
What is coeliac disease?
sensitivity to alpha-gliaden component of gluten
Name some examples of gluten in the diet
wheat, barley, spelt, rye, kamut (cereals, breads)
What happens in the body in coeliac disease?
genetic susceptibility, environmental trigger (consumption of gluten)
T lymphocytes damage mucosal tissue
villous atrophy - loss of jejunal projections and surface area of jejunum so impaired absorption
What are the effects of coeliac disease?
weightloss, lassitude, weakness, abdominal pain and swelling, diarrhoea, oral ulcers, tongue papillary loss, steatorrhoea, dysphagia
What are the typical malabsorption issues associated with coeliac disease?
iron
folate
vitamin B12
fat
What is steatorrhoea and what condition can it sometimes occur with?
excess fat in stool
coeliac disease
How is coeliac disease investigated?
autoantibody test
jejunal biopsy
faecal fat
haematinics - B12, folate, ferritin
What is the effect of a gluten free diet in people with coeliacs disease?
reversal of jejunal atrophy, improved wellbeing, reduced risk of lymphoma
What is coeliac disease skin disease and what are the symptoms?
coeliac disease associated with dermatitis herpetiformis
oral disease - ulceration and blisters
granular IgA deposit in skin and mucosa - itch and blisters (usually shoulders)
All oral aphthous ulcer patients are screened by what?
haematinic assays to detect deficiency
TTG test usually done too - detects IgA
What is pernicious anaemia?
disease caused by vitamin B12 deficiency
Where is the absorption site for vitamin B12?
discrete area of the terminal ileum - only absorption site in the bowel
What causes pernicious anaemia?
lack of B12 in diet - vegans
disease of gastric parietal cells (autoimmune disease)
IBS of terminal ileum - Crohn’s disease
bowel cancer at ileo-coecal junction - resection removes absorptive tissue
What does vitamin B12 need for production?
intrinsic factor from gastric parietal cells
How is vitamin B12 deficiency treated?
diet with adequate B12
vit B12 supplements if prescribed
IM injections of B12 if GI absorption not possible
What has Crohn’s disease been linked to?
infection with myobacteria (paratuberculosis)
Johne’s disease in cattle - milk transmission?
What is a common site for Crohn’s disease?
any site along GI tract plus mouth
ileocoecal region popular site, causes malabsorption of vitamin B12 (pernicious anaemia)
Where does ulcerative colitis occur?
starts in distal part of bowel and moves forward through large intestine (always present in rectum)
What are two key characteristics of ulcerative colitis?
continuous
ulcers in the colon
What are the main differences between ulcerative colitis and Crohn’s disease?
UC continuous, C discontinuous
UC rectum always involved, C rectum involved 50%
UC anal fissures 25%, C anal fissures 75%
UC mucosa gran. & ulcers, C mucosa cobbled & fissures
UC vascular, C non-vascular
UC serosa normal, C serosa inflamed
What are the microscopic features of ulcerative colitis?
mucosal, vascular, mucosal abscesses
What are the microscopic features of Crohn’s disease?
transmural (all layers inflamed), oedematous (blockage of lymphatics, granulomas (giant cells occupying lymphatic drainage systems)
How much of the bowel wall is involved/inflamed in Crohn’s disease?
full thickness
What form between the layers of the bowel in Crohn’s disease?
abscesses and fistulae
What is the appearance of the mucosa in Crohn’s disease like?
cobblestone pattern, areas of oedema between fibrous bands
What is an issue caused by the thickening/inflammation of the intestinal wall in Crohn’s disease?
narrowed lumen can cause issues passing food, obstruction of the bowel
What layers of the intestine does ulcerative colitis affect?
only the mucosal layer
What are the four names of ulcerative colitis which indicate the site of inflammation?
Proctitis - only the rectum
proctosigmoiditis - rectum and sigmoid colon
distal colitis - left side of colon
pancolitis - entire colon
What investigations can be done for inflammatory bowel diseases?
blood tests - anaemia, CRP (C-reactive protein), ESR (erythrocyte sedimentation rate) detect inflammatory process
faecal calprotectin - inflammatory protein
endoscopy, barium studies, leukocyte scan
What is a complication of inflammatory bowel disease?
ulcerative colitis develops carcinoma - risk increases with time
What are the drug treatment options for inflammatory bowel diseases?
immunosuppressive treatment - systemic steroids (prednisolone), local steroids, anti-inflammatories, non-steroid immunosuppressants, biologics (infliximab)
What are the surgical treatment options for inflammatory bowel diseases?
colectomy - cures ulcerative colitis
Crohn’s disease - removal of obstructed bowel segments, drain abscesses, close fistulae (palliate symptoms) - usually results in stoma bag
What is orofacial granulomatosis?
granuloma formation blocks lymphatics
oedema of mouth and/or face, cobblestone appearance
What is the difference between orofacial granulomatosis and oral Crohn’s disease?
Orofacial crohn’s disease when GI tract also involved.
Orofacial granulomatosis when no symptoms further in GI tract
What does “bowel cancer” usually mean?
colonic cancer/colonic adenocarcinoma
Who qualifies for bowel cancer screening in the UK?
anyone from age 50
What are the symptoms of colonic carcinoma?
none
anaemia
rectal blood loss
often no symptoms until tumour causes blockage
What do most colonic carcinomas arise in?
polyps
What does bowel cancer screening aim to detect?
polyps within the surface of the lumen before they progress to malignancy
What kind of polyps form in colonic carcinoma and how long does it take for them to progress to malignancy?
pedunculated or flat
most will bleed due to irritation and trauma
most take 5 years to progress to malignancy
If a colonic carcinoma is removed at the polyp stage what happens?
cancer will not develop and patient no longer has lesion
What patient related factors can increase risk of colonic cancer?
diet - low fibre, high fat, high meat, low veg
smoking, alcohol missuse, lack of exercise
What is Peutz-Jehgers syndrome and how can it manifest orally?
a rare disorder in which growths called polyps form in the intestines
peri-oral melanosis
What are two examples of large intestine conditions that are high risk for progression to carcinoma?
Gardner’s syndrome
Cowden’s syndrome - polyps present in mouth too
What are the surgical options for treating colonic cancer?
resection of colon with anastomosis
bowel brought to surface as stoma
What are three examples of urinary tract obstructions?
renal stones
tumours
prostatic hypertrophy
What does the presence of any bacteria in urine imply?
urine should be STERILE. any bacteria present implies infection
What is the most common bacteria found in UTIs?
E.coli
Staph, fungi, virus and TB also possible
What is cystitis?
bladder inflammation
What can UTIs proceed to cause?
cystitis
What are predisposing factors for UTIs?
poor bladder emptying
low urinary flow rates (in heat or dehydration)
What are the symptoms of a UTI?
dysuria (painful urination)
urinary frequency
cloudy urine
offensive smelling urine
supra-pubic pain
What puts you at risk of a UTI?
people of any age can get a UTI
women>men
people with catheters
diabetes or immunosuppressed
spinal cord injuries or other nerve damage
UT abnormalities blocking flow of urine
Urine, if infected can cause what three infections?
cystitis
renal infection
prostate infection
What UTI can occur in isolation (does not need to have infected urine)?
urethritis - gonococcal infection
What are the symptoms of cystitis?
dark cloudy smelly urine
blood in urine
pain in lower stomach and on urination
peeing often
pain during sex
sick and tired
How are UTIs treated?
MSSU - Mid-stream sample of urine (less contamination) sent for microscopy, culture and sensitivity
increase fluid intake
frequent urination
occasionally ABx required - amoxicillin
What are four examples of conditions that could cause urinary tract obstruction?
1) renal calculi
2) prostatic disease - hypertrophy, malignancy
3) urinary tract strictures
4) external compression
How does prostatic disease cause urinary tract obstruction?
urethra passes through the prostate gland, so any enlargement compresses the urethra
What is prostatitis?
inflammation of prostate
What is benign prostatic hypertrophy?
benign condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine.
How common is benign prostatic hypertrophy?
almost normal, 80% over 80 have BPH
100% if people live long enough
What are the symptoms of urinary outflow obstruction?
slow stream
urgency
nocturia
hesitancy
frequency
incomplete voiding - increases UTI risk
What is the treatment for a benign prostatic hypertrophy?
Initially drug based - alpha blocking drugs, anticholinergic (both to shrink gland size) and diuretics to flush system
Surgery - prostatectomy
Prostatic malignancy starts after what age?
45
What is used for early detection of prostate cancer?
mpMRI (multiparametric MRI)
How is prostatic malignancy treated?
surgery - radical prostatectomy
radiotherapy
hormone treatment - anti-androgens and LHRH analogues, block hormone dependent tumour growth
What are the two types of renal calculi (stone)?
1) calcium and oxalate (radiopaque)
2) uric acid (not radiopaque)
How are renal calculi treated?
Lithotrypsy - ultrasound shock waves break ‘simple’ stones which are too large to pass into smaller pieces
What is polyuria?
passing large volume of urine
what is haematuria?
blood present in urine (frank or microscopic)
What is proteinuria?
not normal, protein passing into urine suggests glomerular disease
What is uraemia?
increased concentration of urea in blood
What does serum urea rise with?
dehydration
What is considered the best measure of renal function?
serum creatinine - kidneys should filter creatinine out of the blood. If kidney function is not normal, serum creatinine is increased and urine creatinine is decreased
What is renal failure?
loss of renal excretory function
loss of water and electrolyte balance
loss of acid base balance
loss of renal endocrine function
What hormonal impacts does the loss of renal endocrine function in renal failure have?
less erythropoietin - so less RBCs produced
calcium metabolism - high serum calcium levels
renin secretion - cause salt and water imbalance
What are the characteristics of acute renal failure?
rapid loss of renal function
usually over hours or days
What are the characteristics of chronic renal failure?
gradual loss of renal function
usually over many years
What are the causes of renal failure categorised into?
pre-renal (in circulation before kidney)
renal (kidney)
post renal (after kidney)
What is a pre-renal cause of renal failure?
hypoperfusion of the kidney - sudden and severe drop in BP (shock) or interruption of blood flow to kidneys from trauma or illness (renal artery or aorta disease)
What are the intrarenal causes of renal failure?
direct damage to kidneys by inflammation, toxins, drugs, infection or reduced blood supply
What are some post-renal causes of renal failure?
renal outflow obstruction due to enlarged prostate, kidney stones, bladder tumour, injury
What are the signs of acute renal failure?
creatinine level >200micromol/L
no urine initially with volume overload - oedema, breathlessness, raised venous pressure
progresses to polyuria
development of hyperkalemia (high potassium) can lead to cardiac arrest
development of uraemia and acidosis
What are the characteristics of the causes of acute renal failure and its management?
usually a pre-renal cause
usually reversible with time, renal support until recovery - dialysis, nutrition
What is glomerulonephritis?
damage to the tiny filters inside your kidneys (the glomeruli) allowing cells and protein to leak into urine.
What can glomerulonephritis progress to?
hypertension
chronic renal failure
What are the symptoms of glomerulonephritis?
haematuria and proteinuria
otherwise a healthy individual
What is nephrotic syndrome?
condition in which kidneys leak large amounts of protein into the urine, complication of glomerulonephritis.
What are the features of nephrotic syndrome?
excessive loss of protein in the urine, >3g in 24hrs
loss of plasma oncotic pressure
tissue swelling (oedema)
hypercoagulable state
What drugs should be avoided in renal disease and why?
NSAIDs - inhibit glomerular blood flow causing interstitial nephritis.
What drug is known to be nephrotoxic and what is it used for?
cyclosporin - steroid-sparing immunosuppressant used in organ and bone marrow transplants as well as inflammatory conditions such as ulcerative colitis, rheumatoid arthritis
What is renal vascular disease and what can cause it?
reduced blood flow to the kidney
atheroma of renal artery/aorta, hypertension causing narrowing of renal artery
microangiopathy - immune reaction causing small blood vessel damage, RBC damage and thrombosis
What are three conditions which can cause immune mediated renal damage?
1) multiple myeloma - plasma cell tumour, clogs kidney causing tubular nephritis
2) Good pasture’s syndrome
3) Vasculitis
What is polycystic kidney disease?
spontaneous or inherited disorder in which clusters of cysts develop in renal parenchyma of kidneys, causing your kidneys to enlarge and lose function over time.
Gene mutation (PK1, 2 or 3)
What defines when someone has reached end stage renal disease?
eGFR <15ml/min
serum creatinine 800-1000micromol/L
How is chronic renal failure managed?
reduce the rate of decline
eliminate nephrotoxic drugs
control hypertension, diabetes, vasculitic disease
correct fluid balance - restrict fluid intake, restrict salt, potassium, protein
correct deficiencies - anaemia, calcium
remove outflow obstruction
treat any infection
What are the signs of chronic renal failure?
anaemia
hypertension
renal bone disease - low Ca, high phosphate, hyperparathyroidism, osteomalacia
What are the symptoms of chronic renal failure?
insidious - may be few
polyuria, nocturia, tired and weak, nausea
What are the dental aspects of renal disease?
careful prescribing
avoid NSAIDs, some tetracyclines
What are the dental aspects of renal failure?
growth may be slow in children - tooth eruption may be delayed
secondary effects of anaemia - oral ulceration, dysaesthesias
white patches - uraemic stomatitis
oral opportunistic infections - fungal, viral
dry mouth and taste disturbance - fluid restriction and electrolyte imbalance
bleeding tendency - platelet dysfunction
renal osteodystrophy - lamina dura lost, bony radiolucencies
What causes dry mouth and taste disturbance in renal failure?
fluid restriction and electrolyte imbalance
What radiographic changes can be seen orally with renal failure?
renal osteodystrophy - complication of chronic kidney disease that weakens your bones, lamina dura lost and bony radiolucencies present
What are the renal functions?
excretory function
water and electrolyte balance
acid base balance
renal endocrine function - calcium, renin, erythropoietin
What is renal dialysis?
a passive process where there is diffusion across concentration gradients. Allows intermittent correction of plasma concentration of small molecules
What are the two types of dialysis?
1) haemodialysis - blood extracted, put through unit and returned
2) peritoneal dialysis - catheter through abdominal wall, dialysing solution introduced to peritoneal cavity and inner lining of peritoneum used as dialysis membrane
What anticoagulant is often added into blood during haemodialysis?
heparin
How are the endocrine functions of the renal system replaced in renal failure?
erythropoietin - replaced by EPO injections to maintain RBC mass
calcium/bone mass maintained by vitamin D supplementation
hypertension control
What is the optimal treatment for end stage renal disease?
renal transplantation
Where is a transplanted kidney placed?
lower than original for easier access
What are the problems with renal transplantation?
rejection - acute or chronic
immunosuppression
high cardiovascular mortality
osteoporosis risk
Is the survival rate better with a renal transplant or dialysis treatment?
renal transplant
What are the important factors to remember when treating a patient that undergoes dialysis?
treat AFTER haemodialysis sessions
normal renal function at first but may reduce with time so check creatinine levels
complications are those of immune suppressants
Can DMARDs be prescribed alongside corticosteroids?
yes
How quickly should DMARDs be escalated to therapeutic dose?
as quickly as possible
Name 5 conditions treated by DMARDs in oral medicine
- lichen planus
- mucous membrane pemphigoid
- pemphigus vulgaris
- Behcet’s disease
- erythema multiforme
What is the difference between DMARDs and NSAIDs?
NSAIDs and corticosteroids have a short onset of action while DMARDs can take several weeks or months to demonstrate a clinical effect.
What are the side effects of the DMARD azathioprine?
bone marrow suppression, red cell aplasia, neutropenia, thrombocytopenia, increased susceptibility to infections
What are the side effects of the DMARD methotrexate?
bone marrow suppression, mouth ulcers, neutropenia, thrombocytopenia, liver toxicity, pneumonitis
What are DMARDs used to treat?
stop or slow the disease process in inflammatory forms of arthritis. DMARDs help preserve joints by blocking inflammation
What are the side effects of the DMARD hydroxychloroquine?
retinopathy, hepatic failure, bone marrow suppression, anaemia, thrombocytopenia, leucopenia
What are the main dental considerations regarding DMARDs?
increased susceptibility to infection
oral ulceration with methotrexate
What are biologics?
subset of DMARDs that may slow or stop inflammation that can damage joints and organs in arthritis and other inflammatory diseases. they are proteins produced by living organisms or by bioengineering
What do Biologics target?
one aspect of the immune system rather than the entire system like conventional DMARDs
How are biologics administered?
IV infusions (would be digested if swallowed)
How do biologics evade the immune system?
they do not carry antigenic segments that may elicit an immune response so they are undetected
What are the four categories of monoclonal antibody and what qualifies them as each category?
Murine - mouse derived
Chimeric - part mouse
Humanized - part human
Human - human derived
When is monoclonal antibody therapy used?
when patients have ‘failed’ therapy with at least two DMARDs
What is etanercept and what is it used to treat?
a fusion protein, Anti-TNF drug which blocks TNF (tumour necrosis factor) and reduces inflammation. used to treat psoriasis, psoriatic arthritis, RA, ankylosing spondylitis
What do monoclonal antibodies end in?
-mab
e.g. infliximab, adalimumab, certolizumab
What fusion protein drug (biologic) is used to treat metastatic colorectal cancer?
aflibercept
What drugs end in -ine? (not all)
anti-histamines
What drugs end in -pine?
calcium channel blockers
e.g. amlodipine
lower BP
What drugs end in -asone?
corticosteroids
e.g. fluticasone, betamethasone
What drugs end in -ital?
sedatives
e.g. butabarbital
What drugs end in -caine?
local anaesthetic
e.g. lidocaine, articaine
What drugs end in -cillin?
penicillin antibiotic
e.g. amoxicillin, ampicillin
What drugs end in -dazole?
antibiotics, antibacterials
e.g. metronidazole, omeprazole
What drugs end in -dipine?
calcium channel blockers
e.g. amlodipine
What drugs end in -dronate?
bisphosphonates
e.g. alendronate, zolendronate, risedronate
What drugs end in -eprazole?
proton pump inhibitors
e.g. omeprazole
What drugs end in -fenac?
NSAIDs
e.g. diclofenac
What drugs end in -mab?
monoclonal antibodies
e.g. denosumab, infliximab
What drugs end in -mycin?
antibiotic, antibacterial
e.g. erythromycin, clindamycin
What drugs end in -olol?
beta blockers
e.g. propanolol,
What drugs end in -olone?
corticosteroids
e.g. triamcinolone, prednisolone
What drugs end in -oprazole?
Proton pump inhibitors
e.g. lansoprazole
What drugs end in -pril?
ACE inhibitor
e.g. ramipril
What drugs end in -semide?
loop diuretics
e.g. furosemide
What drugs end in -zepam?
benzodiazepines
e.g. diazepam
What drugs end in -zodone?
anti-depressants
e.g. trazodone
What are the dental considerations regarding biologics?
increased risk of infection
neutropenia, thrombocytopenia
careful prescribing - liver and renal function
MRONJ
mucosal disease - immunosuppressed
What guidance is given for stopping/continuing biologics for dental surgery?
for most biologics consideration should be given to planning surgery when at least one dosing interval has elapsed for that specific drug.
For higher risk procedures consider stopping 3-5 half-lives before surgery
Are biologics recommended following surgery?
may be recommended post surgery when there is good wound healing (typically around 14 days), all sutures and staples are out and there is no evidence of infection
For patients taking ritixumab (biologic - separate rule for ritixumab), when should treatment be stopped before surgery?
3-6 months prior
What is ritixumab used to treat?
targeted cancer drug (monoclonal antibody)
What proportion makes up the blood in an anti-coagulated sample?
55% plasma
45% red blood cells
plus WBC and platelets