Sunday, April 19, 2015

How to remember the direction of torsion of testis

Torsion of the right testis occurs in the clockwise direction and left testis occurs in the anticlockwise direction.

Saturday, April 18, 2015

Heterophile antibody test, CMV and EBV mnemonic

Hi everyone!

Now - a - days, monospot test is used to diagnose infectious mononucleosis rapidly. 

But heterophile antibody test was used in the past and remembering it is high yield for exams.

Infectious mononucleosis is caused by EBV, which gives a heterophile positive antibody test.

In a minority of cases, infectious mononucleosis is caused by CMV, which gives a heterophile negative antibody test.

How do I remember this?

Mnemonic!

Study group discussion: Tonsils and pharynx review questions

Most common organism causing tonsillitis?
Group B hemolytic streptococcus.

Most common artery which bleeds in tonsillectomy?
Facial artery. 
Paratonsillar vein also known as?
Denise brown vein.
What is facial artery also known as?
Artery of tonsillar hemorrhage.

Why is cleft palate a contraindication to tonsillectomy?
The tonsil is situated at the anterior end of oropharynx. So if the person already has cleft palate and you remove the tonsil.. You are removing an extra support to the palate. This can lead to velopharyngeal insufficiency, that is, nasal voice (rhinolaila aperta) and nasal regurgitation.

15 year old boy presents with recurrent epistaxis which can't be controlled by adrenaline douches. Diagnosis?
Nasopharyngeal fibroma.

Why adrenaline ain't working?
Vessels here are just endothelium lined with no muscle coat.

What are the parts of pharynx?
Oroparynx, nasopharynx and laryngopharynx.

70 year old guy comes with right upper lateral lymph node enlargement. On further questioning, he complains of recent onset reduced hearing on right side. Diagnosis?
Nasopharyngeal carcinoma.

Virus causing NPC?
EBV

What's the pathogenesis of hearing loss in nasopharyngeal carcinoma?
NPC arises from the fossa of rosenmuller.. It's the most common site of origin.  
This, if you remember, is just behind the nasal opening of eustachian tube. So due to blockage of ET.. You get serous otitis media. Which is the cause for deafness. 

While examining a newborn, you notice that there is a mass in the nasopharynx. What is the rationale for checking neural tube defects in such a patient?
Nasopharyngeal bursa represents the embryonic attachment of notochord. So if you see a mass in a newborn in the nasopharynx, the baby maybe suffering from a occult NTD.

A patient comes to you.. He has trismus, fever, and a swelling which is pushing the tonsil medially. Diagnosis? Past history: Molar extraction a few days back.
It's parapharyngeal abscess.

Tuesday, April 14, 2015

Study group discussion: Refsums disease

Ataxia + Ichthyosis + Retinitis pigmentosa  + Don't drink milk.

Associated with which inherited autosomal recessive condition?

Refsums disease.

It's a rare AR disease.. The signs and symptoms of Refsum disease result from the abnormal buildup of a type of fatty acid called phytanic acid. This substance is obtained from the diet, particularly from beef and dairy products. It is normally broken down through a process called alpha-oxidation, which occurs in cell structures called peroxisomes.

Milk, cabbage etc. contain phytanic acid. That's why, they should be avoided.

Study group discussion: Pathophysiology of liquefactive and coagulative necrosis in hypoxia

Why does hypoxia in the brain cause liquefactive necrosis? And why does hypoxia cause coagulative necrosis in all other tissues?

Let's take it step by step!

What's the basis of coagulative necrosis in hypoxia? How does it appear?

The framework and architecture of the cells is maintained.

The reason is - In hypoxia, there is early reduction of ATP. Hence, there is a switch to anaerobic pathways. Increased lactic acid production causes a decrease in pH which results in the inactivation of even the proteolytic enzymes.

The organelles dissolve to some extent, but as the pH increases, enzymes are inactivated, leaving behind the framework.

So.. Why is there no coagulative necrosis in the brain?

There is no anaerobic metabolism in the brain. Hence, no lactic acid to stop the proteolytic enzymes.

Also, in brain there is no supporting matrix. It is all neurons and supporting cells.
In other words,there are no acellular substances. Whereas in other tissues, there is an acellular supporting matrix.

When hypoxia strikes, everything dies in brain.
Hence, liquefactive. In other tissues, the ECM maintains the structure a little bit.

Cool concept. Made me go woah.

Interesting fact: It has been established that casseous necrosis is not necrosis per say, but it is mass apoptosis of macrophages. Robbins mentions it as necroapoptosis.

Study group experience #16


We have 100 members in all 3 groups so we made group 4 :D
I can no longer keep up with the discussions (Internship is draining me T_T)

For this reason, all Whatsapp chats will not be published on the blog, only some :)

Thanks for the tumblr fanmail (:
-IkaN

Saturday, April 11, 2015

Study group discussion: Diabetes and ACE inhibitors

Question: Which of the following drug is best for reducing proteinuria in a diabetic patient?
A. Metoprolol
B. Perindopril
C. Chlorthiazide
D. Clonidine

Friday, April 10, 2015

Study group discussion: Dirty mnemonics

*During a random discussion on Krebs*

There's a mnemonic for the entire sequence in Krebs! It's kinda inappropriate.

Study group discussion: Clinical tips for pediatric rotations

So I'm just going to start with my paediatrics posting and I really really wanna be a paediatrician. Could anyone share any tips on how to be a good paediatrician?

Spend time in clinic/wards..
take histories. Try to make differential diagnosis yourself and discuss it with your teachers..

Yaah..and examine as many kids as you can.

Take a lot of toys / chocolates with you to keep the child busy when you examine.
I used to gift my patients toys and they'd smile so huge! One kid, even though seemed uneducated, told me a thank you! :D

The parents seem really tense, it's a sick child after all. You wanna be very gentle with them and talk cuddly. If you treat the kid more as a patient and less like a child, they are more likely to get pissed.

Good tips, IkaN!

Oh and when you present the case to the attending and the patient's parents are around, don't start with, "Patient, Jane Doe, 2m old female.."
Say, "Child, Jane Doe.."
No one would like their child to be addressed as a patient.

IkaN *thumbs up*
My peds HOD won't let us examine children, if we don't bring candies for them :)

My peads attending said to my friend after a viva, "What did you bring for the kid?"
My friend had not got anything so the ma'am said jokingly, "Nothing for the kid? Okay then, no marks for you!" :P

Awesome tips for peds, IkaN!
They'll be super helpful even during volunteering.

Omg. So you can give them chocolates?

I guess you can give chocolates.. Unless they are lactose intolerant / allergic.
Toys are better, I guess. They keep kids busy for hours!
Give them under parental supervision just to be safe xD

How do you get kids to let you auscultate them? They cry and then you can't hear anything

That's a two people job then, one of you has to distract the baby while the other one auscultates!

And try warming the diaphragm of your stetho a little, the kid probably also cries because it's cold.

Worst case, ask the mother to feed/play with the child.

Distract it, that normally does the trick. Carry a small torch and distract it with the light, it's a trick that usually works.

Study group discussion: Headache in brain tumor

Why do people with brain tumor get headache in the morning?

Intracranial pressure increases in the brain after laying flat all night.

Why does it increase?

Thursday, April 9, 2015

How to remember the side effect of quietapine is cataract

How to remember the atypical antipsychotic that causes cataract
If your lens shine,
you may have been taking quietapine.

Lens shining = Cataract

Related post: Side effects of atypical antipsychotics mnemonic

Study group discussion: Pathological basis of drugs used in the treatment of Alzheimers disease

Discussion on drugs for Alzheimer's.

What is the basic pathology in Alzheimers disease?

Amyloid deposition in the Ach neurons. Hence, decrease acetylcholine in the brain.

Amyloid precusor proteins in the circulation are acted upon by two enzymes -
Alpha secretase: Which forms soluble proteins. These are good.
Beta gamma secretase: Which forms insoluble proteins. These are bad.

These insoluble proteins polymerise to form the plaque. So these insoluble plaque get preferentially deposited in Ach neurons and cause a foreign body reaction.. Leading to inflammation and death of neurons. Hence Alzheimers.

How alpha secretase is good?

Cause it cause soluble products.. These can be washed out by blood. The insoluble ones will precipitate.

There are 5 classes of drugs.. Guess their mechanism based on the pathology discussion!

First class: AchE inhibitors. How do they help?

They will inhibit break down of Ach.. Indirectly, increasing their levels.
Donepezil, Rivastigmine and Galantamine are examples.
They are lipid soluble and cross the blood brain barrier easily. They are also called centrally acting anticholinesterase.

Interesting fact: Nicotine acts both presynaptic and post synaptically to release Ach hence smoking is thought to be protective against AD. However, one of the hypothesis for AD is free radical damage, which can be caused by smoking.

Second class: A drug which will increase activity of alpha secretase.

The name for this drug is deprenyl.

Third class: A drug that inhibits beta secretase.

Beta- gamma secretase has got an inhibitor called tarenflurbil.

Fourth class: These are primary drugs. Inhibit polymerization.

Drug named Tramiprostate

Fifth class: This one removes the pre formed polymers.

Bapineuzumab is the drug.

I love the way you explain things. Starting right from basics!

Extras -

Glutamate antagonists - Memantine. How would antagonism of glutamate help?

Block glutamate excitotoxicity.

Related post: Drugs used in the treatment of Alzheimers disease  http://medicowesome.blogspot.com/2015/03/study-group-discussion-drugs-used-in.html

Tuesday, April 7, 2015

Study group discussion: Infantile hernia

Can anyone mention something about infantile hernia?

The pathology or the physiological hernia that is normal?

Both!

Alright, there are a couple of hernias related to infants that I know about.

One of them is the physiological hernia, which is a thing that happens to all babies during fetal period. So it's normal.
The intestines herniate out of the body of the fetus and rotate 90 degrees at week 6 of development. Then at week 10 they rotate a further 180 degrees and come back into the body. This is the phenomenon that forms the spiral-like location of intestines.

Now there are two pathologies.

One is the Ompholocele, where the intestines fail to come back at week 10.

The other is Gastroschisis where the physiological hernia happens normally but the abdominal wall fails to close so the gastrointestinal system protrudes directly into the amniotic cavity.

Thanks for explaining! Here's a study link!
http://medicowesome.blogspot.ae/2014/09/gastroschisis-vs-omphalocele-mnemonic.html