Your review a 41-year-old woman. Four months ago she developed a deep vein thrombosis and was warfarinised with a target INR of 2.5. She has presented with a swollen, tender left calf and a Doppler scan confirms a further deep vein thrombosis. Her INR has been above 2.0 for the past three months. You organize some investigations to exclude an underlying prothrombotic condition.
What should happen regarding her anticoagulation?
Correct Answer E:
Warfarin: Warfarin is an oral anticoagulant which inhibits the reduction of vitamin K to its active hydroquinone form, which in turn acts as a cofactor in the formation of clotting factor II, VII, IX and X (mnemonic = 1972) and protein C.
Indications:
Patients on warfarin are monitored using the INR (international normalized ration), the ratio of the prothrombin time for the patient over the normal prothrombin time. Warfarin has a long half-life and achieving a stable INR may take several days. There a variety of loading regimes and computer software is now often used to alter the dose.
Factors that may potentiate warfarin:
Side-effects:
Which one of the following is least associated with thrombocytopenia?
Correct Answer B: Rheumatoid arthritis, unlike systemic lupus erythematous, is generally associated with a thrombocytosis. In some cases of Felty's syndrome thrombocytopaenia may be seen secondary to hypersplenism. This however represents a small percentage of patients with rheumatoid arthritis.
Thrombocytopenia Causes of severe thrombocytopenia:
Causes of moderate thrombocytopenia:
A 43-year-old woman is about to start treatment with trastuzumab for metastatic breast cancer.
What is the most important investigation to perform prior to initiating treatment?
Correct Answer B: Trastuzumab (Herceptin) - cardiac toxicity is common.
Trastuzumab:
Trastuzumab (Herceptin) is a monoclonal antibody directed against the HER2/neu receptor. It is used mainly in metastatic breast cancer although some patients with early disease are now also given trastuzumab.
Adverse effects:
A 61-year-old presents for review. She has been having atypical lower back pain for the past two months. An X-ray of her lumbar spine reported raised the possibility of spinal metastases but there is no current evidence of a primary tumour. A series of tumour markers were sent.
Which one of the following is most associated with raised levels of CA 15-3?
Correct Answer C:
Tumour markers:
Tumour markers may be divided into:
It should be noted that tumour markers usually have a low specificity.
Monoclonal antibodies:
Tumour marker Association:
Tumour antigens:
Which one of the following is least associated with eosinophilia?
Eosinophilia: Causes of eosinophilia may be divided into pulmonary, infective and other.
Pulmonary causes:
Infective causes:
Other causes:
Click to expand