Vitamins Flashcards
1
Q
What are the fat soluble vitamins?
A
DrAKE
Vitamin D, A, K, E
2
Q
What factors affect absorption of fat soluble vitamins
A
Bile, pancreases and intestine
3
Q
Which vitamins type are more toxic? Fat soluble or water soluble
A
Fat soluble, because they accumulate in fat
4
Q
What are the mala absorption syndromes with vitamins?
A
Steatorrhea associated with cystic fibrosis and celiac disease, or mineral oil intake can cause fat soluble vitamin defiencies
5
Q
Vitamin A is also called?
A
Retinol
6
Q
What are the four As of Vitamin A?
A
Antioxidant- measles, retinitis pigmentosa, APL and AML (all trans retinoic acid)
Acne (isotretinoin oral, for severe cystic acne)
Aura- constituent of visual pigments
Activation- epithelial cell differentiation into specialized tissue (pancreatic cells, mucus secreting cells). Controls keratin growth (psoriaris) (squamous metaplasia)
7
Q
Defiency of vitamin A leads to?
A
Immunosupression
Night blindness (nyctalopia)
Dry scaly skin (xerosis cutis), corneal degeneration (keratomalacia) Bitot spots (foamy appearnace on conjuctiva)
8
Q
Acute toxicity of vitamin A leads to ___________
A
Vomiting, vertigo and blurred vision
9
Q
Chronic toxicity of vitamin A leads to ________
A
Alopecia, heptatic toxicity, arthralgias, and pseudomotor cerebri
10
Q
Vitamin A has what sources?
A
Liver, leafy vegetables
11
Q
What vitamin A is uses to treat severe cystic acne
A
Isotretinoin
12
Q
Which vitamin is used to treat APL
A
All trans retinoic acid (it leads to the complete differentiation of the granulocytes, so that they are non dividing)
13
Q
Which vitamin A is teratogenic
A
Isotretinoin
14
Q
Why is isotretinoin teratogenic
A
Cleft palate, cardiac abnormalities
15
Q
Therefore in order to be safe, a ____________ and two forms of ______________ is precribed before vitamin A intake
A
A negative pregnancy test
Contraception
16
Q
What is D3’s other name and what is its source?
A
Cholecalciferol
Exposure of stratum basale to sun
Fish, milk, plants
17
Q
What is D2s other name and what is its source?
A
Ergocalciferol
Ingestion of plants, fungi and yeasts
18
Q
Both forms of vitamin D are converted into…..
A
25-OH D3 (hydroxylation at the 25 C) which is the storage form in Liver, and then to the 1,25 (OH)2 in kidney, and the enzyme is 1alpha hydroxylase enzyme. This is the active form
19
Q
25 OH D3 is constantly produced by the ________ and only needed _________
A
Liver
If required by kidney
20
Q
What is the best serum form of vitamin D when tested for status?
A
The storage form
21
Q
What are the functions of vitamin d
A
Increases intestinal calcium and phosphate ions
Increases bone mineralization at low levels
Increases bone resorption at high levels
22
Q
Defiency of vitamin d leads to _______ in _________and ___________ in _______
A
Rickets in children
Osteomalacia in adults
23
Q
What happens in rickets in children due to vit d def?
A
Decreased mineralization of growth plate
24
Q
What are the findings of rickets
A
Bow legs (increased rapid growth of distak forearm and knee) and bone pain, delayed fontanelle
25
What are the x ray findings of children with rickets
Bow legs
26
What are the findings/symptoms of osteomalacia in adults
Bone pain and fractures
27
What are the x ray findings of adults with osteomalacia
Decreased bone density
28
Vitamin d def causes _______tetany
Hypocalcemic
29
What is the cause of osteomalacia
Decreased mineralization of newly formed bone
30
What are the causes of vitamin d def
Mala absorption, decreased sun exposure, poor diet
31
What happens in renal failure in vitamin d def
Renal failure
Secretes less phosphate, so phosphate increases, calcium decreases as they make complexes
Decreases the 1,25 OH D3 inside the body, hence the calcium reabsorption from gut decreases
Hypocalcemia
PTH increases
32
Give _________ to breast fed infants
Vitamin D
33
Defiency of vitamin D is exacerbated by
Dark skin
| Premature birth
34
Excess vitamin d causes
Hypercalcemia, hypercalciuria
| Loss of appetite, stupor
35
What happens in sarcoidosis in granulomatous disease
Activation of macrophages independent of kidney cause the activation of 1 alpha hydroxylase which leads to 1,25 OH D3 formation
36
PTH levels in osteomalacia are?
Increased
37
Vitamin Es other names include
Tocopherol, tocotrienol
38
What is the function of vitamin E
Anti oxidant (protects RBCs and membranes from free radical damage)
39
What is the role of vitamin E with vitamin k?
May alter metabolism of vitamin K, inhibits it
Enhances the effect of warfarin, increases INR in patients
40
What are the symptoms of vitamin e defiency?
Hemolytic anemia
Muscle weakness
Ataxia
Loss of proprioception/vibration
41
What is used to differentiate Vitamin b12 and vitamin E def?
Ataxia and loss of proprioception/vibration seen with vitamin b12 and also megaloblastic anemia, but in vitamin e, it is hemolytic and also there is muscle weakness (diplopia)
42
What is used to differentiate Vitamin b12 and vitamin E def on lab findings?
Hypersegmented nuetrophils and increased serum methylmalonic levels
43
What is the risk of vitamin e excess in children
Enterocolitis in infants
44
Vitamin K includes?
Phytomenadione,
Phylloquinone
Phytonadione
Menaquinone
45
What is the function of vitamin K?
Gamma carboxylation of glutamate residues in clotting factors 2,7,9 and 10, and protein C and S. After usage, it turns into vitamin oxidised, vitamin epoxide reducate reduces it back to its form
46
Where is vitamin K synthesized?
It is synthesized in the intestinal flora
47
What inhibits vitamin K?
Wafarin inhibits vitamin epoxide reductase
48
What is the relation with vitamin K and neonates?
Neonates have sterile intestine, hence neonatal haemorrhage occurs in which there is increased PT and increased aPTT but normal bleeding time
49
What is the relation between antiobiotics and vitamin k?
Antiobiotics kill the normal flora, are unable to synthesize vitamin K, hence increased chances of bleeding
50
What is also not present in breast milk?
Vitamin k
51
What then occurs for neonates in order to orevent neonatal bleeding
Given IM vitamin K injection
52
What is the other name for vitamin C
Ascorbic acid
53
What is the function of vitamin C?
It is an antioxidant
Converts fe three into fe two (non heme), and then it is easily absorbed into the duodenal cell
Hydroxylation of proline and lysine in collagen synthesis
Necessay for dopamine b hydroxylase which converts dopamine to NE
54
Where is vitamin c found?
Fruits and vegetables
55
Some drugs cause methemoglobinemia, and ___________ and ________ is used for ancillary treatment
oxidise fe two into fe three
Vitamin c (reduces it back to its form)
56
What does defiency of vitamin c cause?
Scurvy
57
What are the symptoms of scurvy?
```
Swollen gums
Bruising
Anemia
Hemarthrosis
Perifollicular and subperiosteal hemorrages
Corkscrew hair
```
58
Defiency of vitamin c leads to ____________
Weakened immune response
59
What are the causes of poor wound healing
Zinc and vitamin c
60
Excess of vitamin c leads to
Nausea, vomiting, diarrhea
61
In vitamin c excess, vitamin c metabolizes into _______ and can cause ________
Oxalate
Calcium oxalate nephrolithiasis
62
Vitamin c excess can increase __________in predisposed individuals by increasing ____________
Iron toxicity
| Dietary iron absorption
63
The predisposed individuals in vitamin c related iron overload are
Hemochromatosis
| Transfusion related iron overload
64
Zinc’s function is?
Mineral essential for the activity of 100 plus enzymes
65
What are zinc fingers?
They are proteins attached to zinc and can act as transcriptional factors on dna
66
What is the defiency of zinc symptoms
Hypogonadism
| Decreased adult hair
67
What causes supressed immunity
Zinc and vitamin c
68
Which mineral def causes dysgeusia
Zinc
69
Whuch mineral def causes anosmia
Zinc
70
Zinc defiency leads to the autosomal recessive disorder of __________
acrodermatitis enteropathica
Hyperpigmented skin near the peri anal and around mouth parts
71
Which mineral may predispose to alchoholic cirrhosis
Zinc
72
Kwashiorkor is due to __________
Protein deficit
73
what is the MEALS in kwashiorkor
Malnutrition
Edema (decreased plasma oncotic pressure)
Anemia
Liver (fatty) due to decreases apolipoproteins
Skin lesions (hyperkeratosis, dyspigmentation)
74
What is Marasmus’ cause
Total caloric deficit
75
Is there edema in Marasmus
No
76
What does the diet consist of in patients w marasmus
Diet is deficient in calories but no nutrients are entirely absent
77
Marasmus leads to?
Muscle wasting
78
What is bitamin b1 called?
It is called thiamine
79
What is the function of thiamine? It acts as cofactor for how many enzymes? And what enzymes?
3
Think ATP B
Alpha keto gluterate dehydrogenase,
Transketolase
Pyruvate dehydrogenase
Branched chain ketoacid dehydrogenase
80
A defiency of thiamine will lead to ?
Impaired glucose breakdown, there is atp depletion
81
The atp depletion in thiamine defiency is worsened by?
Glucose infusion
82
What tissues are affected first by thiamine defiency
Aerobic tissues like brain and heart
83
What are the two manifestation of thiamine defiency
Wet beri beri
High output cardiac failure (dilated cardiomyopathy), edema
Dry beri beri
Polynueropathy, symmetrically muscle wasting
84
What are the symptoms of wernicke korsakoffe syndrome
Confusion, opthalmoplegia, ataxia
Classic triad
Plus there is confabulation, personality change, memory loss
85
In wernicke korsakoff syndrome, there is damage to what?
Medial dorsal nucleus of thalamus and mamillary bodies
86
In malnourished and alcoholic patients, what should be given first theoretically and why?
Malnourished and alcoholics with wernike korsakoff: thiamine decreased, glucose also decreased
Give thiamine first so that glucose can be broken down and in order to avoid worsening of wernicke encephalopathy
87
How is diagnosis made in vitamin b1 defiency
Increased rbc transketolase activity after giving b1
88
B1 vitamin is converted into
Thiamine pyrophosphate
89
What is vitamin b2 also called?
Riboflavin
90
What ia the function of riboflavin
Makes FAD and FMN
91
Which enzymes require FAD
Succinate dehydrogenase in the tca cycle
92
What is the def symptoms of b2
Cheilosis inflammation of lips, scaling and fissures at the corners of mouth, corneal vascularization
The two Cs of vitamin b2
93
What is vitamin b3 called
Niacin
94
What is the function of vitamin b3
Component of NAD plus and NADP plus
95
What is vitamin b3 derived from, what does it require
Tryptophan, requires b2 and b 6
96
What is niacin used to treat
Dyslipidemia, lowers levels of vldl and raises levels of hdl
97
What is the defiency symptoms of vitamin b3
Glossitis
Severe defiency leads to pellagra
Dermatitis (c3/c4 dermatome circumferential broad collar rash (casal necklace) hyperpigmentation of sun exposed limbs)
Dementia
Diarrhea
98
______ dermatome circumferential broad collar rash (______necklace) hyperpigmentation of sun exposed limbs) is called
C3/ C4
Casal
dermatitis
99
Defiency of niacin is due to which syndromes and diseases
Hartnup disease, carcinoid syndrome and isoniazid use
100
Hartnup disease is the _________. Defiency of ___________ in the _____________ and on ___________ will lead to nuetral __________ and decreased __________ and decreased _______
Autosomal recessive
Amino acid transporter
Pct
Enterocytes
Nuetral aminoaciduria, decreased absorption from the gut, decreased conversion of tryptophan to niacin
101
Treatment of hartnup disease
Treat with high protein diet and also nicotinic acid
102
In treating patients with hyperlipidemia, _______ is symptom of niacin excess. Treatment?
Facial flushing due to induced prostaglandin
aspirin
103
Besides facial flushing what other symptoms of niacin excess are there
Hyperglycemia hyperuricemia
104
Defiency of niacin_________
Excess of niacin_________
Pellegra
Podagra
105
What is vitamin B5 called
Pantothenic acid
106
What is vitamin b5 essential component of?
Coenzyme A and fatty acid synthethase
107
Defiency of vitamin b5 will lead to
Dermatitis enteritis alopecia adrenal insufficiency burning feet
Very rare widely distributed in foods
108
What is vitamin b6 called
Pyridoxine
109
What is vitamin b6 converted into
Pyridoxal phosphate PLP
110
What is vitamin B6 involved in which reactions
Used in transamination reactions, decarboxylation reactions, glycogen phosphorylase
TGD
111
Where is vitamin b6 involved in? Synthesis wise
Cystathionine, heme, niacin, histamine and neurotransmitters serotonin, epi/nor, dopamine and gaba
112
In heme synthesis, if theres b6 defiency, there is decreased _______ synthesis. Iron accumulates in the rbc because it cannot be ______________. This is called
Heme
Incorporated into heme
Sideroblastic anemia
113
The drug ________ is similar to the structure of ________. Hence it forms _________. Enyzmes mistake it for the active real form and this leads to defiency. Treatment?
Isoniazid
B6
Inactive pyridoxal phosphate
Supplement b6 before isoniazid
114
Defiency of B6 will lead to ________, side effect of medicine ______________
Peripheral nueropathy
Isoniazid
OCPs
115
What ofher symptoms of vitamin b6 defiency besides peripheral nueropathy
Convulsions, hyper irritability
116
What is vitamin B7 called?
Biotin
117
What is the function of vitamin b7?
Cofactor for carboxylation reactions
Pyruvate carboxylase
Acetyl coa carboxylase
Propionyl coa carboxylase
PAP
118
Defiency of vitamin b7 can be due to consumption of which food?
Avidin in egg whites avidly bind biotin
119
Defiency of vitamin b7 can lead to which symptoms
Dermatitis enteritis alopecia
120
Vitamin b7 def can also be due to ________
Antiobiotic use
121
What is the other name for vitamin b9
Folate
122
What is it converted into?
Folate is converted into DHF
Which is converted into THF
Then N5 N10 methylene THF which gives one carbon to ump to make tmp
123
It is important for the synthesis of ___________
Nitrogenous bases like dna and rna
124
Where is folate found
Leafy green veggies
125
Where is it absorbed
Into the jejenum
126
Folate acts as the small reserve pool primarily in the _________
Liver
127
Megalobastic anemia is due to defiency in either _______ or ________
Folate or vitamin b12
128
In megaloblastic anemia, there is increased ________ and decreased _______. There are also __________ seen
Increased mcv
Decreased rbc count
Hypersegmented neutrophils (PMNs)
129
Megaloblastic anemia can also be due to which drugs involved in pyrmidine synthesis leading to folate defiency
Trimethaprim, methotrexate, FU, hydroxyurea, sulfa drugs
130
Which anti epileptic drugs can be involved in folate defiency?
Phenytoin
131
Are there any neuologic symptoms involved in folate defiency?
No
132
In labs, in folate defiency, what are the findings? In terms of homocysteine and methylmalonic acid
Increased homocysteine
| But normal methylmalonic acid
133
Folate defiency is seen in which two common conditions?
Alcholism and pregnancy
134
What should be done to pregnant ladies in order to avoid folate def
Supplement maternal folic for at least one month prior conception and during early pregnancy to decreased nueral tube defects
135
What is vitamin b12 called
Cobalamin
136
What is the function of vitamin b12
N5methyl ThF—————-THF
At the same time
Homocysteine————-methionine
Methionine synthase
Cofactor for methyl malonyl coa mutase
Methylmalonylcoa
||
V
Succinylcoa
Succinyl coa leads to heme synthesis. B6 as cofactor
Succinyl coa leads to TcA cycle
137
Where is vitamin b12 found
Animal products
138
How is it synthesized p, vitamin b12
By microorganisms
139
How is it stored in the liver, as small pool or large pool?
As large pool
140
Vitamin b12 def leads to which type of anemia?
Megaloblastic anemia, macrocytic, hypersegmented PMNs
141
Increased __________ in vitamin b12 defiency leads to which type of nueropathies?
Increased methyl malonyl coa
Peripheral neuropathy and sunacute combined degneration
142
In scd, there is degeneration of the ____________ columns (3)
Dorsal columns, lateral corticospinal tracts, spinocerebellar tracts
143
There is abnormal __________ in subacute combined degeneration
Abnormal myelin
144
In subacute combined degneration, there is more involvement of _______. Symptoms are ______. There is also loss of ______, ______ and ________
```
Legs
Bilateral
Vibration and position sense
Ataxia (falling Q)
Parasthesia
```
145
Vitamin b12 defiency is associated with increased _______ and ________, along with secondary ________ defiency
Homocysteine and methyl malonic acid
Folate defiency
146
Prolonged defiency of vitamin b12 can lead to
Irreversible nerve damage
147
The vitamin b12 defiency can be due to which enteropathies which lead to malabsorption of vitamin b12
Sprue, enteritis, achlorhydria
148
Which tapeworm causes vitamin b12 def
Diphyllobothrium latum
149
Vitamin b12 can also be due to ______ overgrowth and _______ excess
Bacterial
| Alcohol
150
Vitamin b12 defiency is also due to lack of _______
Intrinsic factor, which is vital to absorb vitamin b12
151
Lack of intrinsic factor can be due to which type of anemia?
Pernicious anemia
152
Pernicious anemia is what type of hypersensitivity
Type 2, there is antibodies against intrinsic factor or against the parietal cells which secrete instrinsic factor
153
Pernicious anemia is associated with which type of hla antigens
Hla dr
154
Prolonged pernicious anemia is can lead to
Gastric adenocarcinoma
155
Due to the auto antibodies involved in pernicious anemia, there is what type of inflammation of gastric body
Chronic
156
What other factors contribute to lack of intrinsic factor
Surgical resection of terminal iluem in crohns disease
| Gastric bypass
157
Which type of antibodies are diagnostic for pernicious anemia
Anti intrinsic factor antibodies
158
Folate supplementation can mask the Hematologic symptoms of b12 def but not
Nuerologic symptoms
