Other diseases / pathology

Question 1

What is HIV?

Answer 1

HIV is caused by a retrovirus hijacking reverse transcriptase enzymes within CD4 (T) cells, resulting in immunosuppression.

Question 2

What is the clinical presentation of HIV?

Answer 2

• Unexplained night sweats/fever > 1 month.
• Involuntary weight loss.
• Rash.
• Mouth ulcers.
• Sore throat.
• Lymphadenopathy.
• Recurrent infection.

Question 3

What are the risk factors for HIV?

Answer 3

• Unprotected straight sex.
• Unprotected anal receiving.
• Needle sharing.
• Needle prick injuries.
• Mother > child transmission.

Question 4

What are the tests used to diagnose/monitor HIV?

Answer 4

• ELISA/rapid HIV testing used for initial diagnosis.
• High sensitivity, low specificity so requires 2 +ve tests before diagnosis.
• Stage disease with CD4. <200 diagnoses AIDS.

Question 5

What is the treatment for HIV/AIDS?

Answer 5

HAART (Highly active anti-retroviral therapy):

• Uses 3+ anti-retroviral drugs to slow down the progression of HIV.
• Requires good adherence to treatment, or will not work and will risk drug resistance development.

Question 6

What are the most common AIDS defining infectious organsisms?

Answer 6

• Mycobacterium tuberculosis (Bacterial).
• Pneumocystis jirovecii (fungal pneumonia).
• CMV pneumonitis (viral pneumonia).

Question 7

What are 3 common differentials for HIV? How can they be distinguished?

Answer 7

• CMV.
• EBV.
• Influenza.
• All can be distinguished using a HIV test (ELISA/rapid).

Question 8

What is the most common form of breast cancer?

Answer 8

• Invasive ductal carcinoma.

Question 9

What is the clinical presentation of breast cancer?

Answer 9

• Presence of a lump (90% will be benign).
• Peau d’orange.
• Nipple discharge.
• Nipple inversion.
• Typical cancer signs (e.g. weight loss, tiredness etc.)
• Bone pain (bone is a common metastatic site of breast cancer).

Question 10

What are the risk factors for breast cancer?

Answer 10

• Age
• Female
• FH
• BRCA1/2 mutation
• Alcohol
• Increased breast density
• Radiation
• Other breast disease

Question 11

How does breast cancer screening work?

Answer 11

• Routinely between the ages of 50 and 70.

- Mammogram every 3 years to check for breast cancer.

Question 12

How is breast cancer investigated?

Answer 12

• Mammogram (either screening or ordered as 1st line due to suspicion). Picks up on breast cancer.
• Breast biopsy (fine needle aspiration). Assesses the breast cancer and the type of breast cancer.

Question 13

How does ductal carcinoma present in a breast core biopsy?

Answer 13

• Cords of tumour cells, with the presence of fibrosis.

Question 14

What is the treatment for breast cancer?

Answer 14

1st line:

• Lumpectomy/mastectomy.
• Course of chemo (doxorubicin).

If the cancer is advanced, do chemo BEFORE surgery as this increases the chance of successful resection of the tumour.

Question 15

What are the most common sites of breast cancer metastases?

Answer 15

• Bone (50% - most common)
• Lung
• Brain
• Liver.

Question 16

What is cellulitis?

Answer 16

Acute infection of the skin typically presenting in the leg. Affects the dermis and underlying subcutaneous tissues.

Question 17

What is the clinical presentation of cellulitis?

Answer 17

• Red, swollen, painful skin.
• Usually in leg.
• If severe, may bleed/ulcerate.

Question 18

What are the risk factors for cellulitis?

Answer 18

• Diabetes.
• Immunosuppression.
• Eczema.
• Peripheral venous insufficiency.

Question 19

What are the two main causes of cellulitis?

Answer 19

• Staphylococcus aureus.
• Streptococcus pyrogenes.
• Be careful as it could be MRSA.

Question 20

How is cellulitis investigated?

Answer 20

• Usually, just a clinical diagnosis.
• If bleeding/ulcerated, consider swabbing to check for MRSA.
• If patient requires admission, take blood cultures.

Question 21

How is cellulitis treated?

Answer 21

Normally:
- Flucloxacillin (erythromycin if there is a penicillin allergy).

If MRSA:
- Add vancomycin.

If septic:
SEPSIS-6.

Question 22

What is the process of thrombus formation?

Answer 22

1) Endothelial cells are injured.
2) Clotting factors are released, and platelets aggregate at the site of injury.
3) Forms a thrombus containing platelets and erythrocytes.
4) Fibrin strands adhere to the clot, to make it strong and insoluble.

Question 23

What are the stages of atherosclerosis?

Answer 23

1) Endothelial damage and immune response. Monocytes travel to the site of endothelial injury.
2) Fatty streak formation (initiation). The monocytes differentiate into macrophages, and consume cholesterol - they are now called foam cells. These foam cells then die. It is a buildup of dead foam cells in the endothelium that forms the fatty streak.
3) Plaque growth. The plaque continues to gain size as more and more foam cells are produced and then die, but remains contained by its fibrous cap.
4) Plaque rupture. The fibrous cap on the plaque ruptures, potentially triggering a thrombus to form.