heme update for disability determination vonwillebrand and sickle cell n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Heme Update for Disability Determination ( vonWillebrand and Sickle cell) PowerPoint Presentation
Download Presentation
Heme Update for Disability Determination ( vonWillebrand and Sickle cell)

Loading in 2 Seconds...

play fullscreen
1 / 31

Heme Update for Disability Determination ( vonWillebrand and Sickle cell) - PowerPoint PPT Presentation


  • 52 Views
  • Uploaded on

Heme Update for Disability Determination ( vonWillebrand and Sickle cell). Jennifer M Pearce MD September 2010. vonWillebrand Disease. What is it? --vW protein important for start of clot—attracts platelets and helps them stick to bleeding site

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Heme Update for Disability Determination ( vonWillebrand and Sickle cell)' - levia


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
heme update for disability determination vonwillebrand and sickle cell

Heme Update for Disability Determination(vonWillebrand and Sickle cell)

Jennifer M Pearce MD

September 2010

vonwillebrand disease
vonWillebrand Disease

What is it?

--vW protein important for start of clot—attracts platelets and helps them stick to bleeding site

--Type I vW disease is most common—make the protein but have reduced (not absent) quantities making clotting difficult

--Type II vW—make an abnormally functioning protein

--Type III vW—no protein made and have severe bleeding

clinical manifestations of vw
Clinical Manifestations of vW

In general bleeding is not severe enough to cause disability

Don’t have joint bleeds or spontaneous bleeding

Primarily mucosal bleeding

--nosebleeds

--gum bleeding/dental work

--bleeding with tonsillectomy etc

Menorrhagia

--can be incapacitating but that is rare

--can cause significant iron deficiency

treatment of vw
Treatment of vW

Use of DDAVP as IV or intranasal to raise vW levels

Use of antifibrinolytics

Infusion of blood derived vW protein

Hormonal control of menses

is vw a reason for disability
Is vW a reason for Disability?
  • Essentially NO unless there are unusual extenuating circumstances
sickle cell disease1
Sickle Cell Disease

With all the variants affects 1:600 African Americans, 1:12 are carriers

Can also occur in other ethnic groups: India, Italy, Spain, Saudi Arabia, Greece

Variants: SS, SC, S-Beta Thal, SD

--but in all S is the primary hemoglobin

--SS have, in general, more problems

lifespan in sickle cell
Lifespan in Sickle Cell

Used to be quoted in 20s because of overwhelming infectious deaths in early childhood

Now in 40s and death is usually from endstage heart, kidney or lung disease or hemorrhagic stroke

sickle cell trait
Sickle Cell Trait

One Beta chain has sickle and the other is normal

8% of African-Americans, 0.5% Hispanics, 0.2% Caucasians in United States

Only sickle in extreme circumstances

Increased risk exertional rhabdomyolysis, spenic infarction and renal medullary carcinoma

10-30x increase of exercise induced death—recent NCAA ruling

Generally have no symptoms or issues except in extreme and avoidable situations

hemoglobin
Hemoglobin
  • Normal is 2 alpha chains and 2 beta chains floating in red cell as a foursome—they don’t stick to another foursome
  • In Sickle cell the beta chains have a mutation that, when the hemoglobin unloads oxygen normally, allows the tetramers to stack together in a polymer
the red cell
The red cell
  • Red cells unload their oxygen in the capillaries
  • Capillary diameters are smaller than a red cell
  • When sickle cells deoxygenate their shapes change and if they are still in the capillaries they get stuck
vaso occlusive crisis
Vaso-occlusive crisis

Essentially deep pain from tissue death in the region where blood flow occluded

Often extremities but can be anywhere

Precipitated by anything that slows blood flow through the capillaries or increases rate of deoxygenation

Can happen any time and can last from hours to days—episodic, unpredictable, last from a day to a week

Prolonged pain often requires narcotics

Addiction rare, respiratory depression rare

what leads to a crisis
What leads to a crisis?
  • Anything that leaves the pliant red cell in the capillary long enough to undergo shape change and get stuck
  • Causes oxygen to unload more quickly (increased tissue demand, acidosis)
  • Slows blood flow (cold, vessel constriction, dehydration)
factors that precipitate a crisis
Factors that precipitate a crisis

Physical Cold—a few degrees of change, warmth of clothing, heat in house, swimming

Hypoxia—high altitudes, asthma, sleep apnea

Acidosis—don’t go for the “burn”

Dehydration—and kidneys can’t concentrate

Weather changes

Another illness—URI etc

Hormonal—menstrual cycle

treatment of a crisis
Treatment of a crisis

Pain relief and anti-inflammatories

Start with Tylenol and Ibuprofen, then codeine and on up to morphine/narcotic

Hydration—oral or intravenous

Heat

Rest

Correct inciting factors

other issues anemia
Other Issues=Anemia

Stiff damaged cells are removed rapidly from circulation

--normal non sickle red cell lives 120 days

--normal sickle cell lives 20 days

Marrow can’t keep up so usually hemoglobin is 6.5-9gm/dl instead of >10

impacts growth and development: increased caloric needs of marrow “machine”

other issues overwhelming sepsis
Other Issues=Overwhelming sepsis
  • Primarily in the younger child; starts at 4 months of age

--15% incidence without penicillin prophy

--30-50% mortality (2/3 of deaths within 8 hours)

  • Mostly from ineffective spleen which is gradually “killed off” by sickling
  • Try to prevent with vaccines and prophylactic penicillin
  • Rapid intervention with fevers
other issues stroke
Other Issues=Stroke
  • 10% of kids, peak age for ischemic=7
  • Older adolescents/young adults: hemorrhagic stroke=50% fatal
  • 2/3 incidence of recurrence unless transfused
  • Screen with TCD and MRI/MRA
  • Stroke

--Often silent

--Thrombotic in kids, hemorrhagic in adults

--?reason for learning problems in kids

--mandates transfusions/bone marrow transplant

other issues cardiac
Other Issues=Cardiac
  • Pump wears out faster: cardiomegaly and LVH
  • Pulmonary hypertension, cor pulmonale
  • Iron overload with cardiomyopathy
other issues acute chest
Other Issues=Acute chest
  • Pneumonia vs vaso-occlusive crisis in chest
    • Or a bit of both
  • Rapid progression of symptoms
  • Major cause of death
other issues chronic lung disease
Other issues=Chronic lung disease
  • Concurrent asthma
  • Progress to pulmonary fibrosis
  • Pulmonary arterial hypertension (PAH)
    • Puts additional stress on heart, pumping against higher pressure
    • 30% of adults who were screened
    • 75% on autopsy
    • 40-50% 2 year mortality when severe PAH
renal
Renal
  • Inability to concentrate urine
    • Happens early in life
    • Become dehydrated more easily
  • Hematuria/proteinuria
  • Nephrotic syndrome
  • Renal failure
avascular necrosis
Avascular necrosis
  • SC and SS
  • “death” of femoral/humeral head
  • Pain and disability
other issues vision
Other Issues=Vision
  • Develop retinopathy as age (starts in teens)
  • Can seriously affect vision
other issues miscellaneous
Other Issues=miscellaneous

Aplastic crisis

Gallbladder disease

Skin ulcers: poor healing

Splenic sequestration

In 5-24 mo of age, rapid onset with severe anemia

Life threatening

lifestyle in sickle cell
Lifestyle in Sickle Cell

Uncertainty always about tomorrow

--makes education and employment tough

--average 24 days/year in the hospital

--many days at home unable to work or be in school

--parents lose work days

Some patients more affected clinically than others—why?

Social stigma re narcotic use even if very appropriate

sickle cell cure
Sickle Cell “Cure”

Bone Marrow Transplant

--difficulties with finding donors

--post transplant complications

--New group of disabling/chronic conditions

Gene therapy--?? the future

sickle cell treatment
Sickle cell treatment
  • Chronic transfusion therapy

--iron overload

--red cell sensitization

  • Hydroxyurea—can be wonder drug
    • Increases fetal hemoglobin levels which interfere with sickling
    • Improves anemia, decreases organ damage, decreases incidence/severity of VOC