Helicobacter pylori - More than half of world's population is affected, including you and me probably!!!

Helicobacter pylori

Helicobacter pylori causes the following:

1. Gastritis

2. Gastric ulcers

3. MALToma

4. Gastric carcinoma.

How do we identify H.pylori gastritis?

Many of us would have been taught to look for H.pylori organisms in a gastric biopsy with neutrophils (foveolitis/ foveolar abscess/ lamina propria infiltrates).

This is true!!!..

However, H.pylori is the most common type of CHRONIC GASTRITIS.

Presence of neutrophils only signifies active inflammation and likely presence of organisms in the biopsy.

Signs of H.pylori gastritis:

• Loss of mucin in the surface epithelium and epithelial damage leading to irregularity of the surface.
• Chronic inflammation in the lamina propria with lymphoid aggregates and plasma cells.

How do they look?

H.pylori are 2-4um curved structures.

Where to find them?

• Surface mucin
• Adherent to surface foveolar cells
• Within the foveolar pits

In figure, green circles - indicate plasma cells.
Curved organisms seen within the red circles - Helicobacter pylori.


Differential diagnosis for H.pylori:
Helicobacter heilmannii - twice as long as H.pylori and has 5-7 spirals.

Mönckeberg medial calcific sclerosis - An interesting finding!!

• First described by Johann Georg Monckeberg.
• It occurs most often in patients >50 years of age.
• Calcium deposits are seen in the muscular wall (media) of blood vessels.

• Results in thickening of the arterial wall and loss of elasticity.
• Does not have any serious pathologic consequence, since the lumen is patent.

In figure, arrow points to purple fragmented deposits that represent calcium.

The special stain that would highlight calcium is Von Kossa (stains the deposits black).

"Are You Afraid Of Monster Cells?" - Seminal Vesicle

Seminal vesicle

• Tall columnar epithelial cell lining with a layer of basal cells.
• Presence of golden brown refractile granules in the cytoplasm - LIPOFUSCIN.
• Lipofuscin - Also found in the ampulla of vas deferens and prostatic portion of ejaculatory ducts.

Important and an unusual feature: Presence of MONSTER CELLS - Cells with enlarged, hyperchromatic, irregularly shaped nuclei.

• Do not interpret these cells as malignant cells!!!
• May also be seen in the ampulla of vas deferens.

In figure, arrow points to the pigment; circle points to the MONSTER CELLS.

Arrow - MONSTER CELLS.

It is important to recognise seminal vesicle epithelium for two reasons:

1. Infiltration of seminal vesicle epithelium by prostatic carcinoma (pT3b).

2. To avoid misinterpretation of the seminal vesicle cells (monster cells) as malignant cells in core biopsies of prostate.

Why is identifying ganglion cells important?

Ganglion cells are absent in Hirschsprung disease (also called aganglionic megacolon).

Anatomy:
There are two neural plexus in the intestine - Submucosal (Meissner's) and myenteric (Auerbach's).

Submucosal (Meissner's) plexus - Present just beneath the muscularis mucosa.

In figure, red arrow --> Muscularis mucosa, blue arrow --> muscularis propria.
Space between the two (green line) --> submucosa; Yellow circle --> Submucosal plexus of ganglion cells.


Myenteric (Auerbach's) plexus - Present inbetween the two muscular layers of the bowel wall.

In figure, arrow --> neuronal processes
Circle --> Ganglion cell clusters

Important points:

• Ganglion cells are often associated with neuronal processes and Schwann cells.
• These interconnect and create a neural network throughout the submucosal  layer. 

• Often occur in clusters and may mimic giant cells, epithelioid cells or granulomas.

                               In figure, arrow --> neuronal processes, circle --> ganglion cells.

Diagnosis of Hirschsprung disease:
Absence of ganglion cells in the submucosal and the myenteric plexus.

Other features in favour of Hirschsprung's disease:
Hypertrophy of nerve bundles.
Hypertrophy of muscularis mucosae.