Rogue shit Flashcards
What is methaemoglobinaemia?
Hb oxidised from Fe2+ to Fe 3+. Fe3+ can’t bind to oxygen leading to tissue hypoxia
What causes methaemoglobinaemia?
Congenital
- Hb chain variants eg HbM, HbH
- NADH methaemoglobin reductase deficiency
Acquired
- Drugs eg dapsone, nitrates, sulphonamides
What are the features of methaemoglobinaemia?
Normal pO2 but decreased O2 sats
Chocolate cyanosis
Dypnoea, headache, anxiety
Severe - acidosis, arrythmias, seizures
What is the treatment of methaemoglobinaemia?
Congenital= ascorbic acid
Acquired = methylene blue
What is acute intermittent porphyria?
Genetic condition causing Defect in enzyme required for synthesis of haem
Leads to toxic accumulation off components
What is the inheritance of acute intermittent porphyria?
Autosomal dominant
More common in females
What is the classic presentation of acute intermittent porphyria?
Abdominal, neuro and psych symptoms in 20-40yo woman
Urine turns deep red on standing
What are the features of acute intermittent porphyria?
Abdo p[ain, vomiting
Motor neuropathy
Depression
HTN and tachycardia
How is acute intermittent porphyria diagnosed?
Raised urinary porphobilinogen
Assay of red cells for porphobilinogen
What triggers acute attacks in acute intermittent porphyria?
Drugs, weight loss, surgery
What is the treatment of acute intermittent porphyria?
Avoid triggers
Acute attack - IV haematin/haem arginate
IV glucose
What is cryoglobulinaemia?
Immunoglobulins that reversibly precipitate (clump) at 4 degrees
What are the types of crypglobulinaemia?
Type 1 - monoclonal, associated with myeloma
Type 2 - mixed monoclonal and polyclonal, associated with rheumatoid arthritis, Hep C
Type 3 - polyclonal, associated with rheumatoid
What are the features of cryoglobulinaemia?
Type 1 - Raynaud’s
Arthralgia
Distal ulceration, vascular purpura
Renal involvement - GN
What is the management of cryoglobulinaemia?
Treat underlying condition
Immunosuppression
Plasmapheresis
What is Fanconi anaemia?
Autosomal recessive condition causing bone marrow failure
What are the features of Falcon anaemia?
Aplastic anaemia
Neurological symptoms
Cafe au last spots
Short stature
Increased risk AML
What is hereditary angioedema?
Autosomal dominant condition causing low levels of C1 inhibitor. During acute attacks, uncontrolled release off bradykinin leading to oedema
What are the features of hereditary angioedema?
Painful macular rash
Painless non pruritic swelling of subcutaneous/submucosal tissues
No urticaria
What is the management of acute attack of hereditary angioedema?
IV C1- inhibitor concentrate, FFP
Does not respond to adrenaline, antihistamines, glucocorticoids
What is sideroblastic anaemia?
Condition where red cells fail to completely form haem leading to deposits of iron in mitochondria
What causes sideroblastic anaemia?
Congenital
Acquired - myelodysplasia, alcohol, lead, anti TB medications
What is seen on bloods in siderblastic anaemia?
Hypochromic microcytic anaemia
High ferritin, high iron and high transferrin saturation
Basophilic stippling of red cells
What is Wiskott-Aldrich syndrome?
Primary immunodeficiency due to combined B and T cell dysfunction
X linked recessive
What is the management of aplastic anaemia?
Supportive
ATG - anti-thymocyte globulin
Immunosuppression
Stem cell transplant - high success rate
