Thursday, March 9, 2017
Amiodarone- induced thyroid dysfunctions
Amiodarone, a potent class III anti- arrhythmic drug is contraindicated in thyroid patients or those with subclinical disease. The reason lies in the pharmacokinetic profile of this drug.
The drug has a structural resemblance to triiodothyronine (T3) and thyroxine (T4). In the body, it is metabolized by dealkylation to Desethylamiodarone (DEA), the intrathyroidal concentration of which is higher than the parent drug.
Normal daily recommended intake of iodine for adults is approx. 0.15mg (150mcg). Each 200mg tablet of amiodarone contains about 74.4mg of iodine with 7.4mg (10%) being released as free form. This is roughly 50- fold higher than the normal. Therefore, total body stores may remain increased for upto 9 months after stopping the drug.
High iodine content of this drug inhibits local type-1 5'- deiodinase activity (blocking conversion of T4 to T3) and type- II 5'- deiodinase activity in the pituitary. As a result, TSH is increased initially (mild elevation) and then return to normal or may even decrease in euthyroid patients after weeks, while T4 is normal or raised, and T3 levels decrease.
The increased delivery and uptake of iodine by the thyroid gland may cause increase in hormone production and release, a condition called type-1 Amiodarone- induced thyrotoxicosis (AIT) . In other cases, excessive thyroid tissue destruction due to destructive thyroiditis may lead to type-2 Amiodarone- induced thyrotoxicosis. These are hyperthyroid states!!
Discontinuation of the drug is recommended, if not, then high doses of thioamides and corticosteroids may work in AITs.
Amiodarone may also cause hypothyroidism (AIH) in patients depending upon the iodine status of individuals and prior thyroid disease. Wolff- chaikoff effect is shown by thyroid cells due to failure of thyroid hormonogenesis. Levothyroxine is the drug of choice.
Thats all
- Jaskunwar Singh
Wednesday, March 8, 2017
Fact of the day: Burning the heart to ashes
An interesting fact about heart I read today:
The heart is resilient, literally. When a body is burnt, the heart is the last organ to oxidize. While the rest of the body can catch flame like a polyester sheet on campfire, it takes hours to burn the heart to ash because it's deep inside!
That's all!
Did you know? According to Hindu mythology, when Arjuna cremated the body of Lord Krishna, his whole body turned into ashes, except his heart which was still burning. Arjuna washed the ashes and burning heart into the river.
- Jaskunwar Singh
Munchausen's syndrome
"Psychosomatic disorders are conditions in which a person suffers from significant physical symptoms (causing real distress and disability), that is out of proportion to that which can be explained by medical tests and physical examinations."
Karl Friedrich Von Munchausen, the "Baron of Lies" gave his name to the syndrome. Munchausen's syndrome (now more correctly called factitious disorder in DSM- 5 classification of somatic symptom and related disorders ) refers to patients who imitate illness (may be in an exaggerated form ) for medical attention and care and may even expose themselves to life- threatening operations, amputations, unnecessary medications and toxic treatments.
Lets take an example: A woman presents to hospital with a headache and a dilated pupil. On investigations, scans were normal and no other systemic abnormality seen. Then, a nurse walks into her room and finds the patient self- administering dilating eye drops into the affected eye.
The person has an awareness of the lies they are telling but they surely do it to seek medical care and attention, being unaware of their own motivation and uncontrolled behavior.
Upto one- third of patients in neurology ward suffer from psychosomatic illness and most often, an emotional cause is suspected.
Thats all
- Jaskunwar Singh
Is it okay to wish a man "Happy Women's Day"?
Happy women's day to everyone - Male and female!
Tuesday, March 7, 2017
Study group discussion: PGE and congenital heart diseases
PGE causes clinical worsening in an infant with?
A. PS without VSD
B. Hypoplastic left heart syndrome
C. Obstructive TAPVC
D. Obstruction in Aorta
Let's work this out - choice by choice!
Asbestosis and Silicosis mnemonics
Monday, March 6, 2017
Hyperthermia in Pontine Haemorrhage
Hey guys!
This post will be focused on the pathophysiology of Hyperthermia in Pontine Haemorrhage( which may manifest as the Locked-in Syndrome, remember that super-awesome House episode? <3 )
1. First try the easy simple reason. Hypothalamus has been basically cut off from the body below pons and there has been Haemorrhage. Therefore, there will be a Sympathetic outflow causing peripheral vasoconstriction. Meanwhile the internal visceral organs are still functioning and consequently producing heat. So without hypothalamus, the body's ability to produce heat has transcended it's ability to lose heat.
2. The next reason is a bit "cooler", literally. Our body hates Hypothermia more than Hyperthermia, thanks to evolution. (Ice Age!!!) Now there is no central thermoregulation but peripheral one is still intact. And the peripheral thermoreceptors are much more sensitive to lower temperatures or basically cold environment. Once again, without the Hypothalamus, the body is defending itself too vigorously against Hypothermia as to contribute ironically to Hyperthermia.
3. This reason is the only one which you should know since this will explain how Baclofen, a GABA-B Agonist works to treat this Hyperthermia. Remember the Medial Forebrain Bundle, it connects Hypothalamus to a lot of structures, one of them being Nucleus Raphe in the Pontine reticular formation. This is a very crucial portal in control of Sympathetic nervous system outflow by Hypothalamus. Simply speaking, if the body is hot, Hypothalamus will send inhibitory (GABAergic and Dopaminergic) signals to this nucleus and if the body is cold, it will send excitatory (Glutaminergic and Serotonergic) signals. And apparently this connection is lost in Pontine Haemorrhage, so we substitute it with a drug.
P.S. Now you can guess how Bromocriptine and Apomorphine cause Hypothermia. :)
-VM
Fact of the day: Blood coagulopathies in Familial Hypercholesterolemia
It is known since long that familial hypercholesterolemia is associated with increased risk of cardiovascular disease as a consequence of atherosclerotic plaques in blood vessels. But Its NOT due to high cholesterol levels in blood !!
The cause of such consequences lies in genetics. Genetic aberrations in patients with FH include variations in Prothrombin gene which increases coagulation and clot formation. This ultimately blocks the arteries by forming plaques!
Heart patients with FH also have higher concentrations of Fibrinogen and Factor VIII in their blood in addition to other factors, compared to healthy ones.
People with familial hypercholesterolemia tend to live a longer life than those with low cholesterol levels, suggesting a minor role of high cholesterol in pathogenesis of the disease.
However, cholesterol is still associated with other systemic diseases, though recently LDL has been considered 'good' too!
That's all
- Jaskunwar Singh
Sunday, March 5, 2017
Fact of the day: Proton pump inhibitors and osteoporosis
Chronic PPI usage is associated with an increase occurrence of bone fractures, at present, the likely mechanism of this affect, is not at all clear.
The assumed mechanism is that long-term PPI use leads to decreased intestinal absorption of calcium resulting in negative calcium balance, increased osteoporosis, development of secondary hyperparathyroidism, increased bone loss and increased fractures.
An acidic environment in the stomach facilitates the release of ionzed calcium from insoluble calcium salts, and the calcium solubilization is thought to be important for calcium absorption.
That's all!
Happy studying!
-IkaN
Saturday, March 4, 2017
Facts and Fallacies: Almonds for Migraine
Some people who suffer from migraine are found to be deficient in magnesium and certain vitamins. This proves to be one of the factor for causing such attacks!
Almonds are rich in magnesium and vitamin B2 ( riboflavin ) and contain salicin, an anti- inflammatory agent and ingredient in aspirin. So 10- 12 almonds a day, equivalent to 2 aspirins helps in preventing acute attacks of migraine.
However, for those who are allergic to salicin, almonds may even trigger migraine attacks! Therefore prior testing is important in such cases.
Many recent updates and drugs have become available to treat the attacks but no single one is effective in long- term. For those deficient in magnesium and allergic to salicin, infuse magnesium sulfate solution i.v. over 3- 5 minutes.
That's all
- Jaskunwar Singh
Thursday, March 2, 2017
The story of Medicowesome (With Q&A)
How did Medicowesome start? How do you manage blogging and studying? etc etc.
Fact of the day: Multi- vitamin supplements beneficial for schizophrenics
Recent studies suggest that high- doses of vitamin B help in reducing the symptoms of schizophrenic patients and those with other neuropsychological disorders, when added to the normal treatment in early stages. (Source)
- Jaskunwar Singh
Wednesday, March 1, 2017
Glasgow coma scale mnemonic video
This video on the Glasgow Coma Scale (GCS) was made by Shilika :)
Monday, February 27, 2017
Dealing with psm
Hello.
This was a question from one of our readers..as to how to deal with psm.
Personally I too have dealt with a lot of trauma related to it. So I will share you my own tips and tricks.
Just keep this basic funda in your head while dealing psm. YOU DONT HAVE TO READ EVERYTHING.
Never start reading psm chapters from the very first page. You will be lost in a whirlpool so huge and exhaust yourself to the limits in a matter of hours..and you are bound to never touch the book again.
Now how to approach it..if say your professor is teaching a chapter on contraceptives. Just go through ONLY last three year worth questions..and mark out all the questions just for contraceptives. Never do the whole ten years or five years questions together. Cause you will end up marking the whole book..and that depresses you. So first start last three years.
Once you have done the marking. Psm has one lovely plus point..that apart from the humongous text..it also has charts and diagrams. READ the diagrams first..the flow charts those should be the ones you should learn first. And for answers who don't have flow charts..and have things like components and sub headings of this and that and shit..I suggest just mugg up the names of the sub topics. Just the names only. Make mnemonics, make weird stories..do whatever but you need to learn them.
This trick is important cause think of your examiner. He is tired of reading the same old answers over and over again. So if you go ahead and make beautiful flow charts..or if you just emphasise on the various components and sub headings itself..your job is half done.
And regarding the actual reading of the text. Do it later when you feel more confident..and that time also just stick to the specific answers from previous yr papers.
psm is crazy huge..I have learnt that during exams it was more easy to make up matter to write for psm..but what I didn't remember was that one word of the sub headings or details of the flow chart.
And that's where you go wrong.
Let me know if it helped you and also if any other doubts.
-sakkan
Fish oil for treatment of asthma
Asthma is a chronic, exaggerated and allergic inflammatory response in the respiratory airways to certain allergens that vary according to seasons.
Omega- 3 fatty acids in high- quality fish oils and other products reduce the inflammation by regulating B- cell function. IgE production is reduced, which otherwise acts to cause asthma symptoms and allergic reactions in patients with mild form of asthma.
The fatty acids are used up by the cells in the lining of respiratory passages to produce hormones that tend to "turn- off" certain factors responsible for attracting white blood cells to the site of inflammation such as leukotrienes, interleukins, and other cytokines.
However, these oils are less effective in severe forms of the disease and in the majority of patients taking corticosteroids.
According to a study, prenatal exposure to fish oils (mainly in third trimester) reduces the risk of wheeze and asthma in children.
Thats all
- Jaskunwar Singh
Sunday, February 26, 2017
Ischaemic Preconditioning
Hey, guys!!
This post is on a very interesting condition. To put it in simple terms, Ischaemic preconditioning is a defensive technique adopted by those cardiac myocytes which have faced ischaemia in the past against future ischaemic episodes. There is another defensive procedure called Collaterals but that occurs in chronic ischaemia while Preconditioning occurs in acute conditions.
It was first observed while monitoring the ECG of a patient undegoing coronary balloon angioplasty. When the coronary artery was occluded by inflated balloon transiently, the ECG showed QRS distortions indicative of ischaemia but when it was occluded once again, ECG showed almost normal QRS waveforms.
Mechanism of Ischaemic preconditioning has something to do with Katp channels, the one blocked by Sulfonylureas like Glibenclamide, and also Adenosine receptors. But how exactly these components are involved, isn't clear yet.
That's all!
-VM
Basics of Coagulase test
1) Clumping factor (Bound to cell).
2) Free Coagulase or Coagulase.
8 types of coagulase have been identified .Most human strain forms coagulase A
It is detected by tube coagulase test.
Stay cool and awesome:)
Saturday, February 25, 2017
Beck's triad mnemonic
Acute cardiac tamponade is an emergency condition in which fluid accumulates within the pericardial sac resulting in inability of heart to pump blood. The Beck's triad of medical signs a/w this condition - (mnemonic: DIM )
D- Decreased arterial and pulse pressure
I- Increased venous pressure (JVD)
M- Muffled heart sounds
- Jaskunwar Singh
Friday, February 24, 2017
Right IJV for assessment of right heart hemodynamics
Internal jugular vein of right side is preferred for right heart hemodynamics. This is because-
Aminoglycoside mnemonic
Hello all, let me slip in a quick mnemonic on Neomycin and Amikacin
1.Highest nephrotoxic drug-
Neomycin
2.Highest auditory toxicity is with-
Amikacin
N for N and A for A. Easy one to remember for the MCQs!
That's all!
-Sushrut
Osteogenesis imperfecta mnemonic
Fact of the day: Milk and acidity
Indications for oestrogen therapy mnemonic
Indications for oestrogen hormonal therapy mnemonic: 8Ds
D- Deficiency states of oestrogen
D- Development of secondary sexual characters
D- Diagnosis of pregnancy ( along with progestogen )
D- Dysmenorrhea
D- Depression ( post- partum and perimenopausal )
D- Diastolic dysfunction ( in postmenopausal women )
D- associated Diseases (dermatologic, neurologic, autoimmune)
D- Decubitus ulcer
That's all
- Jaskunwar Singh
Thursday, February 23, 2017
Differentiating gram positive cocci
Delirium and Dementia mnemonics
Delirium- "It is a transient, usually reversible cause of mental dysfunction that results in a wide range of neuropsychiatric abnormalities, mostly presented by elderly as
- waxing and waning type of acute- confusional state
- fall in attention- span
- decreased awareness of surroundings
- low cognition levels."
Causes of Delirium- (mnemonic: DELIRIUM)
D- Drugs (anti- cholinergics, antipsychotics etc)
E- Encephalopathy (Wernicke's)
L- LSD intoxication
I- Infections
R- Respiratory failure
I- Insomnia
U- (v) visual sphere hallucinations
M- Metabolic disorders
Dementia- "A group of neuropsychiatric disorders characterised by chronic and gradual decrease in the ability of person to think, create memories, express emotions and other mental symptoms that affect the general well being."
Causes of Dementia (mnemonic: DEMENTIA)-
D- Degeneration (Primary cerebral)
E- Endocrinal dysfunction
M- Multiple sclerosis
E- Embolisation (vascular pathology)
N- Normal tension hydrocephalus
T- Tumors
I- Infections
A- Alcohol intoxication
That's all
- Jaskunwar Singh
Fact of the day: Cocaine addiction and iron concentration in brain
Also, the increased concentration of iron in brain is accompanied by iron deficiency in rest of the body.
This is possibly attained by decreasing absorption of iron from food and increasing permeability of blood- brain barrier.
- Jaskunwar Singh
Long QT Syndrome
Hey guys this post will be on Long QT syndrome as evident from the title :P.
In a brief introduction, it can be said that LQTS is simply because of abnormal myocardial repolarization most often due to a mutation in ion channel-associated gene. It can lead to fatal ventricular arrhythmias such as torsades de pointes.
So there is increased risk of Sudden Cardiac Death.
It has 3 common variants:
1. LQT1: Loss of function mutation in KCNQ1 gene. And in ECG you see early-onset broad-based T wave.
2. LQT2: Mutation in KCNH2 gene. In ECG T waves are of low amplitude, broad based and maybe bifid.
3. LQT3: Mutation in SCN5A gene. In ECG, there is prolonged ST segment with late-appearing T wave.
We use the ECG to diagnose LQTS and we estimate the probability by using Schwartz score.
Some of the important criteria are :-
1. QTc more than 480msec
2. T wave alternans (Varying amplitudes)
3. Torsades de pointes
4. Notched T waves in atleast 3 leads
5. Syncopal attacks with and without stress
6. Congenital deafness
7. Significant family history
That's all!
- VM
Wednesday, February 22, 2017
Fact of the day: Muscle relaxant of choice during anaesthesia in renal and hepatic failure
Stigmata of Hypercholesterolemia
There are certain physical stigmata of hypercholesterolemia that help the clinician to suspect FH in a patient with a premature cardiovascular disease:
- Xanthelasma (cholesterol deposits on both eyelids)
- Arcus corneae (bilateral; detected by fifth decade of life)
- Tendinous xanthomas (in hand and feet)
That's all
- Jaskunwar Singh
Tuesday, February 21, 2017
Fact of the day: Talking to yourself is a sign of smartness
Micro-organism series: Staphylococcus aureus
Aerobes and facultative anaerobes
Diameter: 1 micrometer
Gram profile: Gram positive Cocci
Arrangement: Grape like clusters
Motility: Non-motile
Sporeing or not: Non-sporing
Capsule: Usually capsulated. Non-capsulated strains have small amount of capsular material on the surface
Ordinary media: They grow readily with temperature range of 10-42°C ( Best at 37°C) and pH around 7.4 - 7.6
Nutrient agar:
You can remember how colony looks by the name STAPHYLOCOCCUS it self.
S - Smooth
O - Opaque
C - Circular
C - Convex
Easily emulsifiable.
It produces golden yellow pigment. Pigment production occurs best at 22℃ and only in aerobic culture. Growth represents "Oil-paint appearance".
Selective media:
Ludlam's medium - Lithium chloride and tellurite.
Mannitol salt agar or salt milk agar- 1%Mannitol, 7.5%NaCl, Phenol red indicator.
Columbia colistin nalidixic acid agar.
Liquid media: Turbidity.
Biochemical Reactions:
Oxidase : Negative
Mannitol: Positive
Indole: Negative
MR andVP: Positive
Phosphatase : Positive (Useful for screening as S epidermidis is negative or slightly positive )
Urease : Positive
Produces thermonuclease enzymes.
Virulence factors :
Extracellular enzymes :
Coagulase (Most virulent)
Lipase
Hyaluronidase
Staphylokinase
Toxins:
Alpha: Most important hemolysin.
Beta: It is sphingomyelinase. Exhibits hot and cold phenomenon.
Leucocidin and gamma lysin is grouped under synergohymenotropic toxins.
9 types of enterotoxins: Responsible for staphylococcal food poisoning. Causes nausea, vomiting and diarrhoea within 2-6 hours.
A, B, C1, C2, C3, D, E, H and I.
Super antigens:
Exfoliative
Enterotoxins
(What are superantigens and how do they work?)
Remember " SOFT PENIS"
S - Skin infections
O - Osteomyelitis and arthritis
F - Food poisoning
T - Toxic shock syndrome
P - Pharyngitis and Pneumonia (Rarely)
E - Endocarditis
N - Necrotizing fascitis
I - Impetigo
S - Sepsis
Sputum - Respiratory Infections
Blood - Septicaemia
Urine - UTI
CSF- Meningitis
Faeces - Food poisoning
Sterile containers should be used
Sterile swabs for specimen from nose/perineum.
Gram stained smears is useful in case of pus, cocci in clusters may be seen.
Treatment:
Sensitive to penicillin: Penicillin G is DOC (Drug of choice)
Penicillin allergy: Cefazolin is DOC
Methicillin resistant S.aureus: Vancomycin
Vancomycin resistant: S.aureus: Streptogramins, Linezolid, Telavancin.
That's all!
Finally done!
Stay awesome :)
Submissions: Adverse effects of Glucocorticoids mnemonic
Mnemonic is glucocorticoids itself!