Systemic Pathology

Question 1

What does HIV cause?

Answer 1

Opportunistic Infections

Tumours

Central nervous system diseases

Question 2

Which opportunistic infections are associated with HIV?

Answer 2

Pneumocystis jiroveci: Pneumonia

CMV: Especially retina and GIT

Candida

Tuberculosis and atypical mycobacteria

Cryptococcus: Meningitis

Toxoplasma gondii: Encephalitis and mass lesions

JC papovavirus: Progressive multifocal leukoencepalopathy

Herpes simplex

Cryptosporidium, Isospora belli, microsporidia: GIT

Question 3

Which tumours are associated with HIV?

Answer 3

Kaposi’s sarcoma: HHV-8

Lymphoma:

• Systemic, CNS or body cavity based
• B cell lymphomas
• EBV

Others:

• Squamous cell carcinoma
• Anus and cervix
• HPV

Question 4

What is this and what are the defining features of these?

Answer 4

Kaposi’s Sarcoma

A. The dermis is expanded by a solid tumour.

B. Fascicles of relatively monomorphic spindled cells, with slit-like vascular channels containing erythrocytes.

C. The nuclei of the tumour cells demonstrate immunoreactivity for HHV-8.

Question 5

Which central nervous system diseases can be caused by HIV?

Answer 5

Progressive encephalopathy: AIDS dementia complex.

Plus opportunistic infections and tumours.

Question 6

What are these?

Answer 6

A. Tumour mass.

B. Perivascular lymphomatous infiltrate.

Question 7

What is the pathology of mycobacteria?

Answer 7

Caseating granulomas

Demonstration of acid fast bacilli

Question 8

What is this?

Answer 8

Cavitating TB

Question 9

What is this?

Answer 9

Granuloma with caseous necrosis

Question 10

Which organs can be affected by mycobacterial infection?

Answer 10

Lung

Lymph node

Bone: e.g. Vertebra

Heart: e.g. Pericarditis

GIT: e.g. Peritonitis

CNS: e.g. Meningitis

Question 11

What is the pathology of sarcoidosis?

Answer 11

Non-caseating granulomas

A diagnosis of exclusion

Question 12

Which organs can be affected in sarcoidosis?

Answer 12

Lung: Scattered granulomas, heal with fibrosis

Lymph nodes: Usually hilar and mediastinal

Spleen

Liver

Heart

Joints

Bone marrow

Skin: Nodules, plaques or macules

Eyes: Iritis, choroid retinitis, lacrimal glands

CNS

Salivary glands

Question 13

What are signs and symptoms of sarcoidosis?

Answer 13

Brain complications
Enlarged lymph nodes in neck and chest
Granulomas and scar tissue in lungs
Enlarged liver
Erythema nodosum
Eye problems
Skin lesions
Heart complications
Enlarged spleen
Join problems (arthritis)

Question 14

What is the pathology of IgG4 related disease?

Answer 14

Inflammation dominated by IgG4 antibody producing plasma cells.

Fibrosis, obliteration of veins.

Question 15

What is this?

Answer 15

Plasma cell rich, inflammatory infiltrate

Question 16

What is this?

Answer 16

Immunohistochemistry for IgG4

Question 17

Which organs can be affected in IgG4 related disease?

Answer 17

Salivary and lacrimal glands: Mikulicz syndrome.

Thyroid: Riedel thyroiditis.

Peritoneum: Retroperitoneal fibrosis.

Liver: Biliary obstruction.

Pancreas: Autoimmune pancreatitis.

Mass lesions: Inflammatory pseudotumour

Question 18

Which organs can alcohol affect?

Answer 18

Liver:

• Fatty change (steatosis)
• Fatty liver hepatitis (steatohepatitis)
• Cirrhosis
• Liver cell cancer (hepatocellular carcinoma)

GI Tract:

• Acute gastritis
• Oesophageal varices

Nervous system:

• Peripheral neuropathy
• Wernicke-Korsakoff syndrome etc.

Cardiovascular system:

• Dilated cardiomyopathy
• Hypertension
• Atheroma (and decreases it!)

Pancreas:

• Acute pancreatitis
• Chronic pancreatitis

Fetal alcohol syndrome

Cancer: Oral cavity, pharynx. oesophagus, liver and breast

Question 19

Which organs can be affected by cystic fibrosis?

Answer 19

Pancreas: Duct obstruction, exocrine atrophy.

Salivary glands: Duct obstruction, atrophy.

Intestine: Meconium ileus.

Liver: Biliary obstruction, cirrhosis.

Lung: Bronchial obstruction, superimposed infection with abscess formation (Staphylococcus aureus, Haemophilus influenzae and Pseudomonas aeruginosa.

Male genital tract: Infertility, absence of the vas

Question 20

What is the pathology of amyloidosis?

Answer 20

Deposition of an abnormal proteinaceous substance in non branching fibrils, 7.5-10nm diameter.

Always contains P component.

Beta-pleated sheet structure.

A variety of proteins can take on this conformation.

Resistant to enzymic degradation.

Question 21

What is the classificiation of amyloidosis?

Answer 21

• *AA:** Derived from serum amyloid A.
  e. g. Crohn’s Disease, Rheumatoid arthritis.
• *AL:** Derived from light chains.
  e. g. multiple myeloma, B Cell lymphoma.

Question 22

What is another classification of types of amyloidosis?

Answer 22

Transthyretin: Mutation

Beta2-macroglobulin: Peritoneal dialysis

Abeta2 protein: Alzheimer’s

Insulin, calcitonin: Endocrine tumours

Question 23

Which staining is used for amyloidosis?

Answer 23

Stains with Congo Red dye.

This shows apple green birefringence under polarised light.

Question 24

What are the clinical features of amyloidosis?

Answer 24

Proteinuria, renal failure.

Restrictive cardiomyopathy, arrhythmias.

Autonomic neuropathy.

Carpal tunnel syndrome.

Macroglossis

Bleeding on injury

Also deposited in blood vessels, endocrine organs, liver, spleen.