Top 10 series: Magnesium sulfate

Here is the video!

By A. P. Burkholderia

Fact of the day: Talking to yourself is a sign of smartness

"Look at that guy, roaming around here and there in the marketplace, muttering words and talking to himself. He seems totally insane. Doesn't he?"

Micro-organism series: Staphylococcus aureus

Hello awesomites here is our first bacteria of micro-organism series - Staphylococcus aureus

Morphology:
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

Cultural characteristics:

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".

Blood agar: Shows beta type of hemolysis when incubated under 20-25% carbon dioxide.

MacConkey agar: Pink colour small colonies (Because it ferments lactose!)

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:

Catalase : Positive
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:

5 types of Cytolytic toxins: Alpha, Beta, Gamma, Delta and Leucocidins
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:

Toxic shock syndrome toxin (TSST)
Exfoliative
Enterotoxins
(What are superantigens and how do they work?)

Disease caused:
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

Laboratory diagnosis:

Specimen and lesions

Pus - Suppurative lesions
Sputum - Respiratory Infections
Blood - Septicaemia
Urine - UTI
CSF- Meningitis
Faeces - Food poisoning

Collection and transport :
Sterile containers should be used
Sterile swabs for specimen from nose/perineum.

Direct microscopy :
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 :)

~Khushboo shaikh,IkaN,and ojas

Submissions: Adverse effects of Glucocorticoids mnemonic

Adverse effects of GLUCOCORTICOIDS:

Mnemonic is glucocorticoids itself!

Introduction to micro-organism series

Hello awesomites!

We have started with micro-organism series where we will discuss bacterias and viruses. But before that let's have a little introduction of Gram positive bacteria and negative bacteria!

Fanconis anemia mnemonic

Hello!

Here's a post on Fanconis anemia!

Fact of the day: Factors that are lost in stored blood

Hello awesomites !

What happens to blood that is stored in blood bank ?

Pierre Robin Sequence mnemonic

Hey Awesomites

Pierre Robin Sequence is one of the most common causes of isolated cleft palate in the newborns. Here's the mnemonic for the triad of symptoms- PRS

P- Cleft Palate only
R- Retrognathia (abnormal posterior position of jaw and maxilla)
S- Support to the lingual muscles is lost (Glossoptosis)

The sequence is known to be caused by genetic anomalies at chromosome 2, 11 or 17.


That's all

- Jaskunwar Singh

A Neurology Case Discussion

Hey guys, let's ponder upon the following case.
Before reading this case, just know that this is a case of cerebellar tumor. Now try to localize the tumor in the cerebellum by taking help of the symptoms of this kid. This will help you in the differential diagnosis given later.

A 4 year old complains of headache, drowsiness and occasional diplopia; he is unsteady on his feet with frequent falls. Examination demonstrates truncal ataxia, sometimes accompanied by incoordination of the limbs; variable ophthalmoparesis and papilledema on fundoscopic examination.

Any guesses on what this could be?

Ok so here goes the case discussion:

Medulloblastoma typically presents with a midline cerebellar syndrome, with hydrocephalus and resultant increased intracranial pressure.
Clinically, it can be distinguished from ependymoma involving the fourth ventricle by the early appearance of nausea and vomiting in the latter, due to involvement of area postrema. Cranial nerve palsies may appear with either tumor, and increasing intracranial pressure is typical of both.
The predominance of signs suggesting primary involvement of vermis distinguishes medulloblastoma from cystic or solid astrocytoma of the cerebellum which typically involves a cerebellar hemisphere rather than the vermis. Although rarely there are midline midline astrocytomas.

You are awesome if you were able to get this one right. :)

-VM

Fact of the day: Genesis of the U wave

Hey guys!!

As you know the U wave in the ecg is seldom seen especially in leads V2 and V3 physiologically especially during bradycardia.
And it is seen pathologically in Hypokalemia.

So how is it generated?
If you are thinking due to repolarization of papillary muscles, let me tell you that this hypothesis is now obsolete.

There are three trending theories at present trying to explain it:

1. Delayed repolarization of the subendocardial Purkinje fibres.

2. Prolonged repolarization of the midmyocardium ( M cells)

3. After-potentials resulting from mechanical forces in the ventricular wall.

That's it!

-VM

Fact of the day: Citrobacter causes brain abscesses in neonates

Citrobacter species are Gram-negative enteric bacilli found in the intestinal tract of humans and animals, and are also present in soil and water.

Why does cyanotic heart disease predispose to brain abscess?

Ever wondered why cyanotic heart disease predisposes to brain abscesses?

Step 2 CK: Treatment of Multiple Sclerosis and mnemonics!

Hello!

This post is all about treatment of Multiple Sclerosis.