BLOOD and NUTRITION

What are different Vit B and what deficiency do they lead to ?

Vit B1 = thiamine = encephalopathy

Vit B6 = pyroxidine = peripheral neuropathy

Vit B9 = folate = mouth ulcers, fatigue - prevention of neural tube defects

Vit B12 = cobalamin = nervous system health = irreversible neurological damage; MHRA alert for Metformin as it can cause Vit B12 deficiency => levels must be monitored

what causes SIADH?

• antidepressants

• antipsychotics

• anticonvulsants

• thiazide diuretics

• all cause HYPOnatraemia (<135mmol/L) => confusion, convulsions, coma

how is SIADH treated?

• strict fluid restriction to prevent further dilution

• vaptans (ADH antagonists eg tolvaptan)

What is pernicious anaemia?

autoimmune condition where body cannot properly absorb Vit B12 from GI tract; caused by body attacking “intrinsic factor” protein => less protein to absorb Vit B12 => fewer RBCs

what vaccines are recommended to sickle cell patients ?

• Pneumococcal vaccine

• haemophilus influenzae type b vaccine

• an annual influenza vaccine,

• lifelong prophylactic penicillin reduce the risk of infection.

• Hepatitis B vaccine - if the patient is not immune.

what are signs of anaemia?

• fatigue

• SOB

• pale skin

• jandice

what Tx is given to sickle cell patients?

• hydroxycarbamide - dose reduce by 50% for SS if eGFR > 60ml/min; avoid in eGFR >30ml/min - watch out for mouth ulcers, signs of infection; LEG ULCERS

• folic acid to aid in RBC production

• life long penicillin proph

what is Glucose 6-phosphate dehydrogenase (G6PD) deficiency?

• reduction of G6PD enzymes => RBCs are not protected from damage => hemolytic anemia

• common in Africa, Asian, Mediterranean and Middle East… NOT whites

what can trigger G6PD?

definitely avoid:

• daponse

• nitro

• Fluoroquinolones

• anti-malarials - quinolones, primaquine - doxy, malorone are SAFE

• Sulfonamides - co-trimox

caution with:

• aspirin

• chloroquine

• sulfonyureas

what is Aplastic anaemia?

life-threatening bone marrow failure, usually autoimmune => no new RBCs, WBCs or platelets => extreme fatigue, frequent infections, easy bruising, and uncontrolled bleeding or nosebleeds

Tx = blood transfusions, immunosuppressive drugs

what is renal anaemia?

complication of CKD => reduction in hormone erythropoietin (EPO) in kidney failure => no RBC production from bone marrow

Tx = Erythropoiesis-Stimulating Agents eg Epoetin alfa, Epoetin beta, darbepoetin alfa (Aranesp)

what is iron deficiency anaemia and how to treat?

• reduction in RBCs due to low iron stores in body

Tx:

oral iron salts - ferrous fumarate 210mg, ferrous gluconate 300mg ferrous sulfate 200mg, sodium feredetate 190mg/5ml, ferric maltol 30mg

monitor within 4 weeks of starting to assess Hb response to oral iron THEN continue Tx for 3 months if Hb response is stable

when can parental iron be given?

only if oral deemed unsuitable or lots of blood loss

examples = ferric carboxymaltose; ferric derisomaltose (MonoFer)

can IV iron be used in preggo?

AVOID in first trimester - can be used in 2nd and 3rd

what is the MHRA alert for IV iron?

risk of hypersensitivity Rxs inc fatal anaphylaxis => close monitoring required

what is iron overload ?

too much iron in body => damage to liver, heart, pancreas

symptoms = fatigue, joint pain, abdo pain, low labido, bronzing of kin

how is iron overload treated?

chelation agents eg IV desferrioxamine

what are different types of anaemias?

• iron deficiency anaemia - not enough iron for Hb to make RBCs

• SS - Hb sickle shape => cannot carry enough O2 and RBCs break down quicker => iron overload as RBCs break down quicker AND release iron into bloodstream

• Renal anaemia = kidneys broke => no EPO => no RBCs

• Aplastic anaemia = bone marrow failure => no RBC, WBC, platelet

• Pernicious anaemia = no Vit B12 absorption from gut => no RBC production

• G6PD = no protective enzymes => RBCs burst

what is Uraemic acidosis?

metabolic complication of kidney failure where the kidneys cannot filter and excrete acids => acid buildup in blood

Tx = sodium bicarb to neutralise acid OR dialysis to remove acids

what is megaloblastic anaemia?

• deficiency in Vit B12 Or folate (B9) => MUST determine the cause before treating

Common UK Cause = Pernicious anaemia

• Autoimmune destruction of intrinsic factor

• → poor B12 absorption

Other Causes

• Gastrectomy

• Ileal resection

• Malabsorption

• Nitrous oxide exposure

• Congenital transcobalamin II deficiency

how is Vit B12 deficiency treated?

• IM Hydroxocobalamin; frequent injections initally to replenish B12 stores THEN every 3 months; often lifelong; ORAL B12 is not effective for malabsorption

what are causes of folate deficiencies?

• poor diet

• preggo

• antiepileptics

Tx = folic acid every 4 months

can folic acid be given alone in undiagnosed megaloblastic anaemia?

NO - as folic acid will improve anaemia BUT can mask Vit B12 deficiency => worsen neuropathy; always safer to give both folic acid and V12

Assess Vit B12 levels to rule out any deficiency then can give alone

what is Neutropenia and how is it treated?

• low neutrophil count (absolute neutrophil count less than 1.5 x 10⁹/litre)

=> increased risk of infections and so sepsis esp in patients on high intensity chemo

Tx = human granulocyte-colony stimulating factor (rhG-CSF) which stimulates production of neutrophils

Examples = filgrastim, lenograstim, pegfilgrastim

what are the different Vitamins and risks associated with their deficiency?

D E K A = fat soluble

Vit B = water soluble

Vit A (retinol) for vision and imunne function

Deficiency = - ocular defects - xerophthalmia (severe dryness of eye) + risk of infections - deficiency is RARE in UK

Vit B:

• B1(brain) = thiamine; nervous system + carb metabolism; deficiency = Wernicke’s encephalopathy, Korsakoff syndrome

• B2 = riboflavin - helps body break down carbs - body doesn’t store it => needs daily refresh; mouth ulcers, glossitis

• B3 = nicotinamide - skin health (no flush unlike Niacin/nicotinic acid) and energy

• B6 = pyroxidine = nerve function ; peripheral neuropathy from isoniazid use OR penicillamine

• B9 = folate; DNA synthesis, RBC production - mouth ulcers, fatigue, megaloblastic anaemia - prevention of neural tube defects

• B12 = cobalamin - nervous system health, RBC production - common in UK, pernicious anaemia - combo with folic acid to treat megoblasic anaemia

Vit C (ascorbic acid) - prevents scurvy

Vit D - bone health + calcium absorption - caused by lack of sun exposure and those with darker skin more affected - colecalciferol = Vit D3. Ca+D = calciium carbonate + colecalciferol

Vit E - to protect cells from oxidative stress

Vit K - necessary for blood Klotting - absorbed in the gut and small intestine => requires bile acids and pancreatice enzymes to relase vitamin and aid abosrption - Menadiol Sodium Phosphate for severe malabosrption