Haem-oncology Flashcards
Define neutropenia
Neutrophils < 0.5 x 109/l
Define neutropenic sepsis
neutrophils < 0.5 +clinical signs of infection or a temp >=38
What is tumour lysis syndrome?
Metabolic abnormalities which occur when a large volume of tumour cells are lysed - usually following chemotherapy
Which tumours are most likely to be associated with TLS?
Acute leukaemias and high-grade lyphomas
What are the metabolic features of TLS?
hyperkalaemia, hypocalcaemia, hyperphosphataemia, raised urate, metabolic acidosis, AKI
How is TLS managed?
IV fluids, treatment of high K - which may include RRT, rasbirucase
What is the mechanism of action of rasbirucase?
Its a recombinant urate oxidase that reduces serum uric acid due to conversion of uric acid into allantoin - which is a readily excretable substance
What is uric acid?
Uric acid is formed when purines are broken down (organic chemicals found in cells)
Its excreted by the kidneys
Excess uric acid can deposit in the tissues and form crystals which can result in inflammation
Raised uric acid can occur if you produce too much or your kidneys don’t clear it
What is allopurinol?
A xanthine oxidase inhibitor - reduces the production of uric acid in the body
What is GVHD?
Immune-mediated disease following allogenic HSCT (and transplantation of solid organs containing lymphoid tissue) that results in a complex interaction between donor and recipient adaptive immunity (APCs of the recipient interact with the mature T-cells of the donor). It can occur even when the donor is perfectly matched.
Describe the clinical picture of acute GVHD
Occurs at < 100 days post HSCT
Typically presents with enteritis, hepatitis, and dermatitis
How is acute GVHD diagnosed?
Histology - skin / rectal / liver biopsy
or by using a clinical diagnosis and scoring system e.g. Seattle Glucksberg criteria
Describe the Seattle Glucksberg staging system for acute GvHD
Stage 1 - rash < 25% SA, bilirubin 26-60, GI fluid loss 500-1000mls/day
Stage 2 - 25-50% skin surface; bilirubin 61-137; GI fluid loss 1000-1500
Stage 3 - > 50% skin surface or erythroderma; bilirubin 138-257; GI loss > 1500mls
Stage 4 - bullous desquamation of the skin, bili > 257; GI fluid loss > 2500
What is chronic GVHD?
> 100days post HSCT
Diverse syndrome with varying clinical features resembling autoimmune disorders such as scleroderma, primary biliary cirrhosis, bronchiolitis obliterans and chronic immunodeficiency. It may be an extension of acute GVHD or may occue de novo
What is typhlitis?
Neutropenic entercocolitis is a life-threatening GI complication of chemotherapy. Symptoms include nausea, abdo distension, pain and tenderness, fever and chills. It has a poor prognosis and successful treatment depends on an early diagnosis. Elective right hemi-colectomy may be required to prevent recurrence.
