Gastroenterology Flashcards
1st Line Treatment of Mild-Moderate Ulcerative Colitis
5ASA - Mesalazine or Sulfasalazine
(No role for methotrexate)
Treatment of Severe UC
IV Steroid Induction + VTEp
1st Line treatment Chrons Disease
no role for 5ASA
Steroid Induction
Maintain with methotrexate or azathioprine
1st Line for Crohns disease with perianal fistula
Infliximab
4 extra-intestinal manifestations that don’t correlate with disease activity in CD?
Uveitis, Pyoderma gangrenosum, PSC and small joint and axial arthritis
EPCLUSA
Sofosbuvir (NS5B inhibitor)
Velpatasvir (NS5A inhibitor)
- 1 pill daily for 12 weeks
- Preferred in those with cirrhosis
- Unable to use in renal failure
MAVYRET
Glecaprevir (NS3/4A)
Pibrentasvir (NS5A Inhibitor)
- 3 tabs daily for 8 weeks
- Ok for use in renal failure
VOSEVI
Voxilaprevir (NS3/4A inhibitor)
Sofosbuvir (NS5B inhibitor)
Velpatasvir (NS5A inhibitor)
- For treatment failure.
Ustekinumab
IL-12, IL23 inhibitor
Targets Th 17 T cell activity
Indicated for induction and maintenance crohns disease.
Serology In Crohns Disease
Positive pANCA - UC
Positive ASCA - Crohns
Sorafenib
Oral Multikinase inhibitor….
Prolongs disease free survival for 3 months in those with advanced HCC
First Line H Pylori Eradication therapy
14 days - Clarithromycin + Amoxicillin + Esomeprazole
(if penicillin allergy, substitute with metronidazole)
2nd Line H h pylori eradication therapy after failure
Quinolone based triple therapy - 10 days of Levofloxicin, amoxicillin + esomeprazole
3rd and 4th line Line H h pylori eradication therapy after failure
Bismuth based quadruple therapy - 14 days Bismuth, teracycline, metronidazole, PPI
Rifabutin based triple therapy - Rifabutin + amoxicillin + PPI
Hep C treatment in Cirrhosis
Compensated cirrhosis (Childs A) - as for no cirrhosis, Epclusa preferred.
Decompensated Cirrhosis (Childs B and C)
- Avoid use of NS3/4A inhibitors Glecaprevir, Voxilaprevir
- Epclusa + Ribavirin is recommended.
Follow-up after Hep C Treatment:
12 weeks post completion of treatment perform HepC RNA PCR - negative PCR at 12 weeks = SVR and is highly predictive of successful treatment.
No followup needed unless:
- Cirrhosis - 6 monthly US for HCC surveillance, monitoring for varicies and osteoporosis.
- Ongoing exposure risk - annual RNA testing, harm reduction strategies.
Vedolizumab
Alpha integrin (Gut selective) inhibitor used for induction and maintenance treatment of CD
(NATALIZUMAB = ALPHA INTEGRIN INHIBITOR, NOT GUT SELECTIVE)
Cutaneous manifestations of IBD
Pyoderma gangrenosum - papule that elvoles into an ulcer with a violaceous boader.
Erythema nodosum - tender eyrthematous nodules on extensor surfaces of lower limbs
Both correspond to disease activity.
Occular manifestations of IBD
Episcleritis - injection of the sclera and conjunctive. Corresponds to disease activity.
Uvetitis - headache, blurred vision, photophobia. Occular emergency requiring prompt referral. Does not correspond to disease activity.
5-ASA’s (5 aminosalicylates)
Sulfaslazine, Mesalazine.
Sulfasalazine - rash, nausea, vomiting, headache.
First line for induction and maintenance in mild-moderate UC.
NO role in CD.
Combination of PO and Topical administration is more effective.
Thiopurines (Azathioprine and 6-mercaptopurine)
Slow onset of action (2-3m) and need tapering steroid to bridge.
Measure thiopurine methyltransferase enzymes genotype or phenotype (preferred) to identify slow metabolises)
A/E:
- Myelosupression
- Hepatitis
- Pancreatitis
- Nausea/vomiting
Rare A/E: Hepatoslpenic T cell lymphoma
Non-melanoma skin cancer
Role of methotrexate in IBD
Effective for induction and maintenance in CD but not UC.
A/E: hepatotoxicity, bone marrow suppression, interstitial pneumonitis.
TNF inhibitors:
Intravenous:
- Infliximab
Subcutaneous:
- Adalimumab
- Certolizumab
Definition of acute severe UC
6 or more bloody stools per day + one or more:
- Temp > 37.8
- HR >90
- Hb < 105
- ESR > 30
Initial Mx of acute severe UC
High dose steroids for 3-5 days and then PO
- 100mg IV Hydrocortisone 6 hourly
OR
- Methylprednisolone 60mg IV daily
Oxford Criteria
Used to assess the need for salvage therapy in acute severe UC.
Assessed on Day 3:
- 8 or more stools per day
- OR 3 or more stools per day with CRP > 45
Assessed on day 7:
- 3 or more stools per day with visible blood
If meets criteria, for salvage therapy
Salvage therapy for acute severe UC
1 -Intravenous Infliximab 5mg/kg
OR
2- Ciclosporin 2mg/kg IV
If perforation or megacolon –> surgery
Induction therapy for proctitis or distal colitis
Note enemas are useful until the splenic flexure.
Combination therapy most effective:
Rectal Mesalazine daily
AND Oral Mesalazine or Sulfasalazine.
If isolated proctitis – use supposetry
If extending >20cm from anal verge - enema
Next step - add rectal corticosteroid (budesonide)
next step - 40mg prednisolone daily, until response, taper over 8 weeks. (consider budesonide if high risk of steroid induced adverse effects)
Next step - Tacrolimus
Maintenance therapy for UC
1 - PO and Rectal 5-ASA - Mesalazine
2 - If severe initial disease or frquent relapses, add Thiopurine to 5-ASA (Azathiopurine 2-2.5mg/kg daily)
Explain thiopurine shunting
Shunting occurs when thiopurines are preferentially metabolised to 6-methyl-mercaptopurine in preference to 6-thioguanine nucleotides.
High 6MMP can lead to nausea and hepatotoxicity,
6TGN is responsible for the theraputic effect, however high levels cause bone marrow supression.
Shunting can be reversed by co-administration of allopurinol 100mg daily.
Main differences in therapy for UC and Crohns
No role for 5-ASA or any rectal therapy in Crohns.
No role for methotrexate in UC.
Induction therapy in mild-mod Crohns
40mg Pred daily until response, taper for 8 weeks.
Induction therapy for Severe Crohns
High dose IV steroids for 3-7 days and then PO
Maintenance therapy for Crohns
- Thiopurines
- Methotrexate 10-25mg/week
- Biologics:
- TNF inhibitors (inflixmab)
- Ustekinumab (IL12/23)
- Vedolizumab (alpha integrin)
Perianal Fistula management
Long term antibiotic therapy (weeks to months)
Metronidazole 400mg 12 hourly (peripheral neuropathy) or Ciprofloxacin 500mg 12 hourly
TNF alpha inhibitor
Preventing recurrence of postoperative Crohns
After surgery CD will predictably recur at or proximal to the anastomosis.
Prevention:
- Metronidazole
AND
- Thiopurine, TNF inhibitor, or a combination of both.
Microscopic Colitis
Normal macroscopic appearance, however inflammation on biopsy - categorised into:
- Lymphocytic colitis
- collagenous colitis
Typically in older women with other autoimmune conditions.
Associated with medications - NSAIDS, SSRI, PPI
Mx: Stop offending medication. Supportive management with loperamide. Second line is PO budesonide.
Colorectal Ca screening in IBD
UC - Start 8 years after diagnosis and screen 3 yearly.
- If has PSC, risk is significantly increase. Screen from diagnosis and annually.
- Factors that increase risk a lead to annual screening:
- Active disease, PSC, FMHx <50 years, stricture, dysplasia.
CD - if >1/3 of bowel involved then screen for CRC as per UC. Some increase in small bowel Ca risk but very rare so not screened.
Adverse Effects of Anti-TNF
Infection
Melanoma risk if doubles
Drug induced lupus
High risk features in CD
Age <40
Perianal disease
High titre ASCA
NOD 2 mutation - associated with fibrostenotic complications.
Smoking, deep ulcers, strictures
High risk features in UC
< 40 years
Extensive disease
PSC
Deep ulcers
High titre pANCA
Anti-TNF
Infliximab, Adalinumab, Golimumab
- Work better in CD than UC
Adhesion molecule inhibitor for IBD
Vedolizumab
Works better for UC than CD
Gut specific and very little systemic immunosuppression, therefore good for people with issues with infection.
Anti-IL 12/23
Ustekinumab
ONLY for CD
Vaccination and immunosuppression
Don’t give live vaccines 3 weeks prior to, or for 3 months after immunosuppression.
Live vaccines: VZV, MMRV, Japanese E, Yellow Fever.
Vaccination and immunosuppression
Don’t give live vaccines 3 weeks prior to, or for 3 months after immunosuppression.
Live vaccines: VZV, MMRV, Japanese E, Yellow Fever.
Most common gene mutation in Lynch Syndrome (HNPCC)
Autosomal dominant Inherited mutation of DNA mismatch repair genes.
Most common mutation MSH2 60%, MLH1 (30%).
Testing for HNPCC?
Gene testing is expensive.
Test for micro-satellite instability which is a surrogate marker for DNA mismatch repair gene dysfunction.