Showing posts with label Oncology. Show all posts
Showing posts with label Oncology. Show all posts

Monday, May 28, 2018

Complications of massive blood transfusion


Hii everyone! 

Massive blood transfusion is defined as

Complications from massive transfusion include :
1) Hypothermia
2) Hypocalcemia - because citrate present in transfused blood is a calcium chelator, it decreases the available calcium.
3) Acidosis - as citrate is acidic in nature.
4) Hyperkalemia - as Hydrogen ions are present in excess due to acidosis, it is compensated by H+ loss in urine and K+ is regained back into blood. So this causes hyperkalemia.
5) Hypokalemia - in stored blood, the Na+-K+ pump is less functioning,  so there is decrease in intracellular K+ in stored blood.  But after blood transfusion, the Na+ K+  pump again starts functioning and increases intracellular K+, this leads to decrease in the available K+ outside the cell causing hypokalemia.
6) Dilutional coagulopathy - massive blood transfusion leads to dilution of clotting factors . It later manifests as DIC-like leading to multiorgan failure and death.

Thanks for reading.

Madhuri.

Complications of blood transfusion

Hii everyone!
This post is about the complications from a single blood transfusion.

1) The most common complication is febrile nonhemolytic tranfusion reaction(FNHTR). -- this occurs due to anti-HLA antibodies in the recipient which kills WBCs leading to release of interleukins and cytokines which are pyrogens. So the treatment is antipyretics.
2) Urticaria - it is due to IgE antibodies in plasma. So we give antihistamines to control it.
3) Hemolytic transfusion reaction - due to antibodies against RBCs. This is rare.  It may occasionally occur due to clinical errors in pretranfusion tests.
4) Infections - bacterial infection due to faulty storage, hepatitis, HIV, malaria.
5) Air embolism
6) Thrombophlebitis
7) Transfusion- related acute lung injury - usually occurs within 6 hrs after transfusion.

Hope this helps.

Madhuri

Friday, May 25, 2018

Hematology Diagrams

Hello Awesomites! :D

I made these diagrams during my exams.
I kept in mind the details of cells.
Hope it will help.



-Upasana Y. :)

Tuesday, May 15, 2018

AML and ALL differentiating features.


Hello awesomeites !

Today let us find out the difference between AML and ALL on the basis of cell morphology, cytochemistry and immunophenotyping.

So, Acute Leukemia is the presence of blasts >=20% either in peripheral blood or bone marrow.

Myeloblasts in AML and Lymphoblasts in ALL are the two main types

Cell morphology:

Myeloblasts:  The characteristic feature is the presence of Auer rods with moderate amount of cytoplasm and cytoplasmic granules and multiple nucleoli
Lymphoblasts:  They have a scanty cytoplasm no granules and nucleoli are not present
Many a times differentiating the two on morphological basis isn’t feasible. So we take the help of cytochemistry.

Cytochemistry:

Myeloblasts:  are myeloperoxidase(MPO) and Sudan black B (SBB) positive
                         Monoblasts which are a part of the myeloid lineage are nonspecific esterase (NSE) positive
Lymphoblasts:  are periodic acid Schiff (PAS) positive
MPO stains the enzyme within the azurophilic granules and is the most specific while SBB stains the lipid membrane of the azurophilic granules and is most sensitive for myeloid differentiation .
Even after this if we aren’t able to differentiate then we take the help of immunophenotyping

 
Immunophenotyping:

It is performed by flow cytometry.
The sample either bone marrow or peripheral blood is stained with antibodies and the cells are allowed to fall freely in a single file across a beam of laser (this is the over simplified version of it :P).
The laser used is Blue laser of wavelength 488nm. When the laser beam hits the cells some of it gets scattered to the sides and is known as the side scatter which is a measure if the granularity of the cells. While the rest of the beams travel in the same line without deviation and is called as the forward scatter and is a measure of the size of the cells.
Neutrophils are the cells with the highest side scatter.
Staining of the cells with antibodies helps in subtyping acute leukemias on the basis of CD markers.

Here is a list of CD markers on varies cells of myeloid and lymphoid lineage

B cell markers:
CD19: present on all B cells
CD10: immature B cells
CD20: mature B cells

T cell markers:
CD3: present on all T cells
CD4 CD8 CD2 CD5 CD7 are some of the other markers present on various T cells

Myeloid markers: CD13 CD33 CD117

Stem cell markers: CD34

Monocyte markers: CD14 CD64

NK cell markers: CD16 CD56
CD45 is present on all leucocytes a.k.a pan leucocyte marker 


That’s all for now, hope this helps in better understanding of AML and ALL!
Keep calm and keep studying!
Stay awesome!
-          Ashish G. Gokhale

Saturday, February 24, 2018

Tumor lysis syndrome and rhabdomyolysis: Why does calcium decrease?

Doubt in response to you post on tumor lysis syndrome: What is the mechanism behind hyperphosphatemia causing hypocalcemia in tumor lysis syndrome? Wouldn’t the tumor cells also release calcium, thus leading to hypercalcemia? Asked via email

Friday, February 23, 2018

HPV vaccines

Hello Awesomites!

HPV infection can cause:
-cancers of the cervix, vagina, and vulva in women;
-cancers of the penis in men; and
-cancers of the anus and back of the throat, including the base of the tongue and tonsils (oropharynx), in both women and men.

3 vaccines are available :-
1.Gardasil (6,11,16,18)
2.Cervarix (16,18)
3.Gardasil 9

Is HPV vaccine only for girls?
No, it is for both boys and girls.

Age 11-26 years.
Then what is that 9-11 years or 11-12 years criteria?
Actually most of the vaccination programme for adolescent is in that age group. So to avoid that extra visit it has been scheduled so.
What about beyond 26 years?
It is not required because such cases are either already exposed or already infected.
In <14 years -2 doses is needed to mount same immunity.

Dose 2 or 3 .
-interval between the doses should be of 4 weeks.

Route intramuscular

Type capsid proteins.

Pregnancy is a contraindication. But if did vaccination then no need to abort.

For the doubts regarding vaccination, you should consult your physician.

-Upasana Y. :)

Friday, February 16, 2018

Immunomodulators mnemonic

Hello Awesomites :)

Let's work out an interesting way of remembering a few Immunomodulators and Chemotherapeutic agents today!

These mnemonics were submitted to us by Mikey.

1. SIRolimus
    Is it nephrotoxic? Does it cause pancytopenia?
    - Kidney SIRvives. It causes panSIRtopenia

2. MycophenolATE side effects:
    - M: Marrow suppression
    - ATE: for GI effects: Nausea, cramping and abdominal pain

3. What do you use Azathioprine for?
    - *Auto*thioprine - *Auto*immune conditions, as well as Rheumatoid Arthritis, Crohn's disease and glomerulonephritis

4. What is the MOA of Basiliximab and what are it's side effects?
 Say: Basilik, THE Reptile in aisle 2
    - THE: Tremor, Hypertension, Edema
    - It is an IL- 2R monoclonal antibody

5. What is the MOA of Trastuzumab and what is it used for? it's side effect?
    - It is a therapeutic antiobody againts HER2/neu receptor
    HER Breasts and Stomach *trust*ed you!
    - Used for Breast and Gastric cancers
    But, it hurts Heart too!
    - Causes Cardiotoxicity.

- Compiled by Riya

That's it!
Have an awesome day, you guys!

Thursday, January 25, 2018

Lymphoma and Leukemia Translocations Mnemonic


Hello everyone!

Here's an intuitive way to remember the chromosomal translocations involved in various lymphomas and leukemias.
































Hope this helps. Happy studying!

-- Ashish Singh

Thursday, August 10, 2017

Factors increasing iron absorption in the intestine mnemonic

Hello! Long time, no see!

Did you know a number of dietary factors influence iron absorption?

Ascorbate (vitamin C) and citrate increase iron uptake in part by acting as weak chelators to help solubilize it in the duodenum.

Friday, July 21, 2017

Lung Cancer Subtypes

Subtypes of lung cancer:-
1. Squamous cell cancer-
Most common variant in India.
Smoking is a risk factor.
Central in location.
Local growth is surgically resectable.
Cavity formation is seen.

2. Adenocarcinoma-
Most common variant of lung cancer overall.
Most common lung cancer among non smokers.
Peripheral in location.
Transbronchial spread i.e. it arises at one lobe and spreads to the another lobe.

3. Small cell carcinoma/Oat cell carcinoma-
Most aggressive variant.
Smoking is a risk factor.
Central  in location.
It exhibits micrometastasis.
It has worst prognosis.

4. Large cell carcinoma-
Observed in Non smokers.
Peripheral in location.
This is associated with Estrogen production which manifests as Gynecomastia.

I hope this will help you to distinguish between the various subtypes.

Thank you
-Md Mobarak Hussain (Maahii)

Thursday, July 20, 2017

Megaloblastic Anemia


1. Why do we get " Megaloblasts" in Megaloblastic anaemia?
2. Why we get anaemia in Megaloblastic anaemia?
Megaloblastic anaemia is called so due to presence of " Megaloblasts" in bone marrow.
What are " Megaloblasts" They're gigantic, abnormally BIG RBC-precursors seen in bone marrow. WHY do we see them ?
It needs some conceptual understanding.                           
Normally, RBC-precursors are big cells which divide rapidly as they mature & become progressively smaller as they divide while maturing towards mature-form of RBCs.  Now, the problem begins in Megaloblastic anaemia that this cell-division is impaired due to lack of nutrients ( Folate & Vitamin B12).  Vit B12 & Folate are critical for normal DNA synthesis & cell maturation.                                                             It's also described by a complex -term called " Nuclear-Cytoplasmic Asynchrony".
As DNA-synthesis is impaired, nuclear maturation of RBC-precursors get slowed up & could not match with the pace of cytoplasmic maturity/development. This DEFECTIVE NUCLEAR MATURATION halts cell-division & those big "MEGA" RBC-precursors remain as Big, MEGA, gigantic " Megaloblasts" in bone marrow giving the name as " Megaloblastic anaemia". Moreover, these " Megaloblasts" do NOT mature enough to get released into the peripheral blood & most RBC-precursors undergo " apoptosis " or apoptotic-death in bone marrow ..this  causes anaemia in Megaloblastic anaemia.

Hope this helps some of you to understand the basic concepts.

-Md Mobarak Hussain (Maahii)

Sunday, July 16, 2017

Fact of the day: Liquid biopsy for cancer detection

Hey Awesomites

We have known since long that surgical biopsies done routinely in cancer patients to diagnose and detect progression of the disease may increase the risk of carcinogenic changes in the cells in future, due to the changes that had prompted the biopsies.

A non - invasive and painless diagnostic tool that replaces the cutting is "liquid biopsy" that finds the hidden cancer cells anywhere in the body. The liquid biopsy is taken from a simple blood test to look for microscopic pieces of DNA circulating in the blood that contains genetic mutations causing tumors to spread, among billions of other DNA that were in the blood.
A year ago, a circulating tumor DNA test was approved by FDA that spots these mutations.


Thats all
- Jaskunwar Singh

Saturday, July 15, 2017

Poikilocytosis

Red blood cells

Also known as erythrocytes, is the most common type of blood cell and the principal means of oxygen transport in the body.

The normal biconcave shape is the essential feature of its biological function.
Through various stages of development and maturation, RBC loses its nucleus and most organelles in order to accommodate maximum space for haemoglobin.
This feature of RBC is critically affected by genetic and acquired pathological conditions.

Poikilocytosis is the term used to denote the variation in the shape of red blood cells.
Let's look at the major abnormalities in the shape of RBCs and the conditions in which they are seen:

1. Spherocyte - hereditary spherocytosis, autoimmune haemolytic anaemia, ABO haemolytic disease of the new born

2. Schistocyte - thalassemia, hereditary elliptocytosis, megaloblastic anaemia, iron deficiency anaemia and severe burns

3. Irregular contracted red cells - drug and chemical induced haemolytic anaemia, unstable haemoglobinopathies

4. Target cell (a type of leptocytosis)- iron deficiency anaemia, thalassemia, chronic liver disease and after splenectomy

5. Sickle cell (drepanocyte)- sickle cell anaemia

6. Tear drop cell - myelofibrosis, underlying marrow infiltrate

7. Crenated red cell - in blood films due to alkaline pH, presence of traces of fatty sustances on the slides or film allowed to stand over night

8. Acanthocyte - post splenectomy, chronic liver disease, Abetalipoproteinemia, McLeod blood group phenotype

9. Burr cell - uremia, liver disease, artifact

10. Stomatocyte - hereditary stomatocytosis, chronic alcoholism

11. Ovalocyte - hereditary ovalocytosis, hereditary elliptocytosis, severe iron deficiency anaemia

The diagram given represents the corresponding cells





Credits to: Shivani Mangalgi.

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

Friday, July 7, 2017

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

Saturday, July 1, 2017

Fact of the day: The link between Alzheimer's and Cancer

Hey Awesomites

People with a history of cancer are less likely  to suffer from Alzheimer's in the advanced age, while those with Alzheimer's disease are less likely to get cancer.
Source )

- Jaskunwar Singh

Thursday, June 22, 2017

Immunotherapy for Prostate cancer

Hey Awesomites

Immunotherapy is now an emerging and much promising intervention in the treatment of prostate cancer, apart from the traditional cancer treatments - chemotherapy, radiation and surgery.

Friday, May 19, 2017

No cyanosis in cyanide poisoning. Why?

I was reading about cyanide poisoning today and saw "Cherry red skin" in the clinical manifestations. I know that carbon monoxide poisoning causes a cherry red color to blood. But why cyanide?

The curiosity lead to this post.

In normal cellular metabolism, most adenosine triphosphate (ATP) is generated from oxidative phosphorylation. .

Cyanide avidly binds to the ferric ion (Fe3+) of cytochrome oxidase a3, inhibiting this final enzyme in the mitochondrial cytochrome complex. When this enzyme's activity is blocked, oxidative phosphorylation ceases. The cell must then switch to anaerobic metabolism of glucose to generate ATP.

Anaerobic metabolism leads to the formation of lactic acid and the development of metabolic acidosis. Hydrogen ions produced by ATP hydrolysis are no longer consumed in aerobic ATP production, exacerbating this acidosis. Serum bicarbonate decreases as it buffers excess acid, leading to an increased anion gap.

Despite an ample oxygen supply, cells cannot utilize oxygen because of their poisoned electron transport chain. This functional (or "histotoxic”) hypoxia is particularly deleterious to the cardiovascular and central nervous systems (especially the basal ganglia).

Because of the decreased utilization of oxygen by tissues, the venous oxyhemoglobin concentration will be high, making venous blood appear bright red.

Therefore, despite hypotension, apnea, and/or bradycardia, the patient does not usually appear cyanotic in the setting of cyanide poisoning.

Clinical features:
Central nervous system toxicity is the most prominent in cyanide toxicity – Headache, anxiety, confusion, vertigo, coma, seizures.

Which should you suspect cyanide poisoning?
Victims of fires
Reported ingestions
Treatment with sodium nitroprusside

Antidote:
Hydroxocobalamin
Sodium thiosulfate
Nitrites (to induce methemoglobinemia)

That's all!
-IkaN