Saturday, July 15, 2017
Fact of the day: Gonorrhea and vulvovaginitis
Friday, July 14, 2017
Evaluation of Pseudophakia
Clinical evaluation of a case of Pseudophakia.
Pseudophakia is a term used to describe the condition wherein an artificial intraocular lens is implanted after surgery for cataract.
On history - History of cataract surgery present.
On examination -
1) Deep Anterior Chamber (the posterior support for the iris is lost as the IOLs are thinner that the natural lens)
2) Conjunctival flap and subconjunctival hemorrhage ( seen only in recent cases)
3) Scleral/ Corneal incision and scar.
4) Iridodonesis (tremulous iris)
5) Jet black pupil
6) Shimmering light reflex from the IOL.
Oculocardiac Reflex
Oculocardiac Reflex/Aschner phenomenon.
This is one of the trigeminovagal reflexes produced on digital massage of eye. Digital massaging of the eyeball is done to lower intraocular pressure after producing a retrobulbar or a peribulbar block. But rarely....this event is followed by cardiac depression, asystole and even death. The afferent is by the ophthalmic division of trigeminal nerve which relays in the visceral motor nucleus of the vagus nerve. The efferent is carried by the parasympathetic vagus nerve to the heart. It is most commonly seen in pediatric cases during squint surgery.
It is not seen very commonly in adults and in other surgeries as the procedure would involve just one eye and massaging of this eye is not sufficient to produce bradycardia normally.
Treatment: atropine or glycopyrrolate . Cardiopulmonary resuscitation might be needed in severe cases.
Thursday, July 13, 2017
Bulbar and Psuedobulbar palsy : Overview
Here's a short overview of Bulbar and Pseudobulbar palsy !
If there is a lesion is at the level of Medulla - affecting the motor neurons : The nuclei of the cranial nerves - you get LMN Palsy features - Flaccid paralysis of 9 10 11 12 Cranial nerves. This is called a 'Bulbar palsy' as the bulb (Medulla) is involved in isolation.
Now , essentially when the fibres supplying the motor neurons of the bulb (your Medulla) are affected themselves - that is any neurons above the nucleus of the nerve - it's a UMN lesion. So you get 9 10 11 12 UMN palsy - Spastic paralysis.
This would be Pseudo-bulbar as same CN involved but lesion is above the Medulla
So Pseudobulbar you'd have a hyper active gag reflex while it'll be absent in Bulbar.(Mediated by 9th cranial nerve).
You'd have a Hot potato like speech in Pseudobulbar as your vocal muscles of larynx and tongue are spastic. - (10th and Cranial 11th. )
While you'd see a nasal twang in Bulbar (also called Donald duck speech)
As your soft palate doesn't abut against the nasal cavity (due to LMN flaccid paralysis). Also causing nasal Regurgitation of food in Bulbar.
So they both essentially present with 9 10 features and some of the 11 12. Hence one is Pseudo and the other is true Bulbar.
Psuedobulbar would also have emotional problems. Called Pseudobulbar affect (as the higher fibres are involved - lesions are generally multiple infarcts in the cortex).
A few important causes :
Psuedobulbar palsy :
- Vascular = B/L Frontal lobe lesion , B/L Pontine stroke , Vascular dementia = Multi infarct dementia.
- Central Pontine Myelinolysis
- Degenerative = Multiple sclerosis , Motor neuron disease
- Cerebral Palsy
_________________________________
Bulbar palsy :
- Guillian Barre Syndrome
- Polio
- Motor neuron Disease
- B/L Medullary infarction
Hoping this helped !
Happy studying guys !
And stay awesome !!
~ A.P.Burkholderia.
Myopathies series - Part 1
Tuesday, July 11, 2017
Pathophysiology of laboratory findings in tumor lysis syndrome
Which of the following electrolysi abnormalities will you see in tumor lysis syndrome?
Answer either high, normal or low for each of these - calcium, phosphate, potassium, uric acid.
Answers:
Labs in tumor lysis syndrome -
Hypocalcemia
Hyperuricemia
Hyperphosphatemia
Hyperkalemia
Why?
When cancer cells lyse, they release potassium, phosphorus, and nucleic acids, which are metabolized into hypoxanthine, then xanthine, and finally uric acid.
This leads to:
Hyperkalemia can cause serious — and occasionally fatal — dysrhythmias.
Hyperphosphatemia can cause secondary hypocalcemia, leading to neuromuscular irritability (tetany), dysrhythmia, and seizure, and can also precipitate as calcium phosphate crystals in various organs (e.g., the kidneys, where these crystals can cause acute kidney injury).
Uric acid can induce acute kidney injury not only by intrarenal crystallization but also by crystal-independent mechanisms, such as renal vaso-constriction, impaired autoregulation, decreased renal blood flow, oxidation, and inflammation.
Crystal-induced tissue injury occurs in the tumor lysis syndrome when calcium phosphate, uric acid, and xanthine precipitate in renal tubules and cause inflammation and obstruction.
That's all!
-IkaN
Causes of microcytic erythrocytosis
A high RBC count combined with a low mean volume is seen in:
1. Thalassemia minor, either alpha or beta
2. Polycythemia vera with iron deficiency
3. Secondary polycythemia (hypoxia) with incidental iron deficiency.
Differentiating thalassemia minor from polycythemia vera:
The RBC size distribution curves reliably distinguish between thalassemia minor and polycythemia with iron deficiency.
RDW is elevated in iron deficiency. It is normal in thalassemia minor.
That's all!
-IkaN
Type 2 RTA pathophysiology, notes and mnemonic
What causes Type 2 RTA?
Defect in proximal bicarbonate reabsorption - resulting in a hypokalemic hyperchloremic metabolic acidosis.
The defect in proximal reabsorption of filtered HCO3- in effect leads to decreased proximal NaCl reabsorption and a tendency for salt wasting. This causes hyperaldosteronism - leading to increased K secretion by the distal nephrons.
Sunday, July 9, 2017
Staphylococcal Scalded Skin Syndrome vs Bullous Impetigo
How do you differentiate Staphylococcal Scalded Skin Syndrome (SSSS) from Bullous Impetigo (BI)?
The exfoliative toxins are restricted to the area of infection in BI. In SSSS, infection is diffuse.
In BI, bacteria can be cultured from the blister contents. Cultures from blisters are negative in SSSS.
Blood cultures are usually negative in SSSS (positive in BI).
In SSSS, Nikolsky sign is positive. It is negative in BI.
In BI, patients are usually not ill appearing.
That's all!
-IkaN
Pills of knowledge in Ophthalm- squint and frontal eye field
Mentally challenged people may have a squint as the frontal eye field in the brain cortex is involved in ocular movements as well. It also may explain why somebody's eyes go crazy when they're starting into nothingness.
That's all!
-Sushrut Dongargaonkar
Saturday, July 8, 2017
Settings for mechanical ventilation
Treponemal and nontreponemal tests for syphilis (notes + mnemonic)
Nontreponemal tests include:
Rapid plasma reagin (RPR)
Venereal Disease Research Laboratory (VDRL)
Toluidine Red Unheated Serum Test (TRUST)
Mnemonic:
Do not trust VDRL rapidly.
Features of non treponemal tests:
They are based upon the reactivity of serum from infected patients to a cardiolipin-cholesterol-lecithin antigen.
Used for initial syphilis screening due to their relatively low cost, ease of performance, and ability to be quantified for the purpose of following response to therapy.
Specific treponemal tests include:
Fluorescent treponemal antibody absorption (FTA-ABS)
Microhemagglutination test for antibodies to T. pallidum (MHA-TP)
T. pallidum particle agglutination assay (TPPA)
T. pallidum enzyme immunoassay (TP-EIA)
Chemiluminescence immunoassay (CIA)
Features of treponemal tests:
Treponemal tests have been more complex and expensive to perform than nontreponemal tests. Thus, they have traditionally been used as confirmatory tests for syphilis when the nontreponemal tests are reactive.
Treponemal tests are qualitative only and are reported as "reactive" or "nonreactive"
Once a patient has a positive treponemal test, this test usually remains positive for life. Thus, these tests are generally not useful for confirming a diagnosis of syphilis in a patient with prior treated disease.
That's all!
-IkaN
Postural variations in pulmonary edema and embolism
Patients with pulmonary edema prefer to be in an upright position, while those with pulmonary embolism prefer flat position.
This is because in cases of edema, there is excess fluid accumulation in lungs, which limits respiratory movements. In upright position, the fluid will settle down and thus it lowers the pressure in pulmonary vessels which makes it easier to breathe.
On the other hand, in case of pulmonary embolism, the patient is placed in left lateral decubitus (durant maneouver) and Trendelenburg position immediately. The air embolus moves through the right side of heart to enter into the lungs. But in Durant's maneouvre and Trendelenburg position, the embolus gets trapped in the apex of the heart and so does not get transported through pulm arteries to enter the lungs.
Check this link for more detail on venous emboli management
Thats all
- Jaskunwar Singh
Friday, July 7, 2017
New drug launched for Sickle Cell Disease
Parkinson's disease associated with melanoma: Research update
Hey Awesomites
Patients with movement disorder such as the Parkinson's are at four-fold higher risk for malignant melanoma, and vice versa. This is likely due to mutual genetic, environmental and pathogenic ( immune system ) abnormalities and factors that they both share, as suggested by a research study at Mayo clinic.
( Source )
- Jaskunwar Singh
Thursday, July 6, 2017
Causes of dilated cardiomyopathy mnemonic
Hi awesomites!
Here's a short note on causes Dilated cardiomyopathy.
It's mostly idiopathic.
Other causes are:
1. G enetic Mutation
2. Myocarditis
3. Alcohol abuse
4. Drugs
5. Pregnancy
6. Hemochromatosis
Mnemonic. GMM ADPH
That's all :)
H@Mid
Why do newborns have a higher heart rate?
Hey guys!
Have y'll ever wondered why do babies have heart rates as high as 160s?
Answer:
Babies have a high proportion of Body Surface Area to heart than that in adults. Therefore, in order to maintain adequate blood flow, baby's "li'l heart" has to pump more often to cover the "large Body Surface Area"!
I hope y'll find this interesting!
Till then, stay awesome!
-Rippie
Nasal Encephalocele vs Nasal Glioma
Both nasal encephalocele and nasal gliomas are congenital conditions in which there is herniation of glial tissues and meninges into the nasal cavity through the foramen cecum.
Both the masses are seen in the nasal cavity as bluish masses with nasal obstruction.
Nasal gliomas have no communication to the brain as the communication gets detached after the fusion of cranial bones in late IUL. Gliomas are firm and non compressible mass.
Encephalocele also presents as nasal mass with obstruction. The swelling increases in size in response to coughing. Most common site is occipital and then frontal.
Bilateral compression of the internal jugular vein also leads to the increase in the size of mass called as Frustenberg Test.
Frustenberg test is positive in encephalocele and negative in gliomas.
Investigation of choice for both is MRI.
Hope this helps!
Ashita Kohli
Wednesday, July 5, 2017
External Cephalic Version : An overview
Breech Presentation and Transverse Lie.
Contracted Pelvis - ECV can cause fetal Hypoxia if the pelvis is small already
Happy Studying !
And as always ,
Stay Awesome !
Tuesday, July 4, 2017
Pancreatic cysts
1. When you see no epithelial lining to the cyst on microscopy, think of a pseudocyst
2. When you see a multilocular cyst with a central scar, think of a serous cystadenoma; if it is absent, think of a mucinious cystadenoma. Both are " NOT" connected to the main pancreatic ductal system
3. When you see a sizable (more than 1cm) growth within the pancreatic duct, think of IPMN!
That's it!
Monday, July 3, 2017
Mnemonic- Causes of saddle nose
Saddle nose is a nasal deformity due depressed nasal dorsum which may be bony, cartilaginous or may involve both.
Causes- HOT SALT
H- Hematoma
O- Operative (during SMR)
T- Trauma
S- Syphilis
A- Abscess
L- Leprosy
T- Tuberculosis
Hope this helps!
Ashita Kohli