Histopath 1: Systemic Disease Flashcards
Name some infective and non-infective causes of systemic disease
infective:
- HIV
- mycobacterium (TB)
Non-infective:
- Sarcoid
- IgG4-related Disease
- alcohol
- CF
- amyloid
What are the main complications of HIV infection?
- Opportunistic infections
- Tumours
- CNS diseases
Which are the main opportunistic infections in HIV?
- Pneumocystis jiroveciàPCP pneumonia
- CMV
- Candida
- TB and atypical mycobacteria
- Cryptococcus
- Toxoplasma gondii
- JC papovavirus
- Herpes simplex
- Cryptosporidium, Isospora belli, microsporidia à GIT
Which of the HIV opportunistic infections causes PCP pneumonia?
Pneumocystis jirovec
Of the HIV opportunistic where does CMV affect?
especially retina and GIT
- I.E. CMV oesophagitis
- Stains brown in immunohistochemistry
Which of the HIV opportunistic infections causes meningitis?
Cryptococcus
Which of the HIV opportunistic infections causes encephalitis and mass lesions
?
Toxoplasma gondii
Which of the HIV opportunistic infections causes progressive multifocal leukoencephalopathy?
JC papovavirus
Of the HIV opportunistic where does Cryptosporidium, Isospora belli, microsporidia affect?
GIT
Name the main tumours found in HIV and the viruses that cause them
- Kaposi’s sarcoma (HHV-8)
- Lymphoma (systemic [CNS, or body-cavity based], B-cell lymphoma, EBV)
- Other (SSC, anus & cervix, HPV)
What is seen in histopathology in Kaposi’s sarcoma?
- Dermis expanded by solid tumour
- Made of spindle-shaped cells–infiltrated by HHV-8
- HHV-8 identified in nuclei of tumour cells
What are the main CNS diseases found in HIV?
- Progressive encephalopathy = AIDS dementia complex
- Plus, opportunistic infections and tumours
- CNS lymphoma
What are the main histopathological features of Mycobacteria (i.e. TB)?
-
Caseating granulomas – in immunocompetent people
- Cavitating TB– predilection to apices of lungs
- Caseating granuloma = necrotic centres–like cottage cheese
- Demonstration of acid-fast bacilli
Which organs can mycobacteria (TB) affect?
- lung
- heart
- lymph nodes
- GIT
- bone
- CNS
What are the characteristics of sarcoid? How is it diagnosed?
- NON-caseating granulomas – collection of macrophages with a cuff of lymphocytes around
- Diagnosed as a diagnosis of exclusion
Which organs does sarcoid affect?
- Lung
- Liver
- BM
- CNS
- Lymph nodes
- Heart
- Skin
- Salivary glands
- Spleen
- Joints
- Eyes
How is Ig4-related disease characterised?
- Inflammation dominated by IgG4-AB producing plasma cells
- Fibrosis and obliteration of veins
- Plasma cell rich inflammatory infiltrate
- Immunohistochemistry for IgG4
What are the IG4-related diseases?
- Salivary and lacrimal glands: Mikulicz syndrome
- Thyroid: Riedel thyroiditis
- Peritoneum: Retroperitoneal fibrosis
- Liver: Biliary obstruction
- Pancreas: Autoimmune pancreatitis
- Mass lesions: Inflammatory pseudotumour
Name some conditions caused by alcohol
- Liver: fatty change (steatosis), 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
- Cancer: oral cavity, pharynx. oesophagus, liver and breast
- Fetal alcohol syndrome
Which organs does cystic fibrosis affect and how?
- 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
Which organs does cystic fibrosis affect and how?
- 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
What is amyloid?
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
What are the classifications of amyloid?
What is the staining used in amyloid?
- Stains with Congo Red Dye [TOP]
- Shows apple-green birefringence under polarised light [BOTTOM]
