Mock14 Peptic Ulcer

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Patient with known peptic ulcer disease, presented with hematemesis, OGD done showed bleeding gastric ulcer. Labs showed hypercalcemia. PMH: osteoarthritis on NSAID, smoker, CKD on dialysis.

Define an ulcer?

An ulcer is a local defect of the mucous membrane or the skin due to gradual disintegration of the surface epithelial cells
OR
Breach of the continuity of skin, epithelium or mucous membrane caused by sloughing out of inflamed necrotic tissue.

Risk factors of PUD?

H-pylori infection
NSAIDs
Smoking

How can NSAIDs causes PUD?

Topical irritant effect on the epithelium
Impairment of the barrier properties of the mucosa
Suppression of gastric PG synthesis (inhibitors of cyclooxygenase)
Reduction of gastric mucosal blood flow
Interference with the repair of superficial injury

What is H. pylori?

Gram negative microaerophilic spiral bacteria found in the stomach

After taking a gastric biopsy during endoscopy, what test can be done to the biopsy to confirm H. Pylori infection?

CLO test (campylobacter like organism)

Describe how it's done?

It depends on urease production by H. pylori

A gastric mucosal biopsy is taken during gastroscopy and is placed in a medium containing urea and an indicator such as phenol red,

Urease production by H-pylori converts urea to ammonia which increase pH changing the colour (yellow to red) → positive test

How does H. Pylori manage to survive in the gastric acidic medium?

By production of urease which converts urea to ammonia which increase pH.

Other test of Pylori?

Urease breath test
Test for the stool antigen

How can H. Pylori colonize the stomach?

Flagella, which allow the bacteria to be motile in viscous mucus
Urease, which generates ammonia from endogenous urea, thereby elevating local gastric pH around the organisms and protecting the bacteria from the acidic pH of the stomach
Adhesins, which enhance bacterial adherence to surface foveolar cells
Toxins, such as that encoded by cytotoxin-associated gene A (CagA), that may be involved in ulcer or cancer development by poorly defined mechanisms

Q: How does h pylori induce gastritis?

By production of:
Ammonia (from urea).
Proteases
Phospholipases
→ damage gastric mucosa and cause inflammation

What's the type of cells in the gastric antral mucosa?

Simple columnar with goblet cells

What are the types of gastric cancer caused H. Pylori infection?

Adenocarcinoma
MALT (Mucosal associated lymphoid tissue tumour)

Which immune endocrine disease is associated with it?

Hashimoto thyroiditis

How to treat symptomatic H. Pylori infection?

7 days twice daily of
Full dose of PPI + metronidazole 400 mg + clarithromycin 250mg
or Full dose of PPI + amoxicillin 1g + clarithromycin 500mg

What's the mechanism of action of proton pump inhibitors?

PPI binds irreversibly to H⁺/K⁺ ATPase enzyme (proton pump) on gastric parietal cells and blocks secretion of H⁺, which combine with Cl⁻ in the stomach lumen to form HCL.

What are the actions of gastric HCL?

Activate pepsinogen to pepsin (which help in proteolysis)
Provide optimal PH for action of pepsin
Stimulating small intestine to release secretin and CCK.
Enhance absorption of Ca and Iron in small intestine.
Antimicrobial

What are the other possible causes of hematemesis in this patient?

Hypercalcemia → increased gastrin release → increased HCl production → Mucosal erosion → bleeding

What are the common causes of hypercalcemia?

Malignancy
Hyperparathyroidism (PTH adenoma)
Renal failure

The patient had a history of recurrent renal stones, what's the possible cause?

Hypercalcemia

What's the commonest cause of primary hyperparathyroidism?

Solitary parathyroid adenoma

What's the meaning of adenoma?

Benign epithelial neoplasm that takes glandular pattern
or non-epithelial from glandular origin.

How can the parathyroid glands be localized?

Sestamibi scan (pre-operative)
Frozen section (intra-operative)

Where can they be found if not in their normal location?

In superior mediastinum as it shares same embryological origin with the thymus (3rd pharyngeal pouch)

What's frozen section and it is performed in simple words?

It's a pathological laboratory procedure to perform rapid microscopic analysis of a specimen.

Can you explain more the steps?

The surgeon takes a small piece from a tissue or tumour and send it for analysis
The pathologist freezes it and section it and immediately cut it
The section will be stained and reported immediately when the results come out

Why paraffin based histopathology is not convenient for intraoperative pathological testing?

As it takes a week for paraffin to embed through the tissues

What's the treatment of parathyroid adenoma?

Excision

The patient underwent excision of the 4 parathyroid glands. You were given the following pathology report:
1 gland 0.2 g chief cells.
The other 3 glands ranging from 0.08 to 0.09 g composed of oxyphilic and fat cells.
What's your interpretation?

Parathyroid adenoma in one gland with involution to the other glands

What's the histological features of parathyroid adenoma?

Mainly chief cells and few oxyphil cells and surrounded by non-neoplastic thyroid tissue separated by a fibrous capsule.

How does this compare to parathyroid hyperplasia?

Parathyroid hyperplasia composed primarily of chief cell hyperplasia and with water-clear cells.

What are the types of hyperparathyroidism? And the treatment of each?

Primary hyperparathyroidism (solitary adenoma) → treated by excision.
Secondary hyperparathyroidism (chronic renal failure) → treated with dialysis.
Tertiary hyperparathyroidism (after renal transplant) → treated firstly by conservative management, but if more than 12 months go for surgery.

How to treat acute hypercalcemia?

Hydration
Forced diuresis
Bisphosphonates: IV pamidronate
Calcitonin

isurg

Mock14 Peptic Ulcer