Wednesday, March 9, 2011

Sickle Cell Anemia: A Review for the Pediatric Dentist

Resident: Adam J. Bottrill
Date: 09MAR11
Region: Providence
Article title: Sickle Cell Anemia: A Review for the Pediatric Dentist
Author(s): Fonseca, Marcio A. et al.
Journal: Pediatric Dentistry
Page #s: 159-169
Vol:No Date: 2007
Major topic: Sickle Cell Anemia
Minor topic(s): None
Type of Article: Topic Summary and Discussion

Main Purpose: Provide a comprehensive review of Sickle Cell Anemia

Key points in the article discussion:

I. General:

A. Sickle Cell Anemia (SCA)is an inherited defect that affects the structure and synthesis of hemoglobin.
B. Alpha and Beta Thalassemia and SCA are the most common types of hemoglobinopathies worldwide.
C. SCA: most frequent genetic disorder. Found often in African, Mediterranean, Middle Eastern, Indian, Caribbean, Central American and South American.
D. Comprises sickle cell trait and sickle cell disease (SCD)
E. SCD: hemolysis, chronic organ damage, unpredictable acute life-threatening complications.
G. Trait: Benign. 8% of African Americans and 10-30% of equatorial Africans.
H. HbS (sickle hemoglobin) carriers protected from Malaria.

II. Pathophysiology:

A. Polymerization of deoxygenated HbS... "single, indispensable event in the path..."
B. Lifespan of sickle RBC=12-17 days (normal=120).
C. Sickle cells caught in slow-flowing venular side of microcirculation.... increased adhesion to endothelial walls and local hypoxia increased HbS polymer formation and spread of occlusion to adjacent vasculature. Increased inflammation.
D. Problem becomes "erythrocitic sticking" rather than simple "sticking". Other problems include adhesion, hemolysis, deformation.
E. Symptoms arise from chronic endothelial damage instead of acute erythrocyte formation. "chronic inflammatory vascular disease"

III. Systemic manifestations:

A. Symptoms begin within 1st 6 mo of life: evolving organ damage with intermittent pain and pulmonary complications.
B. Genotype most effects the clinical severity.
C. "Crisis" usually occur due to other illnesses, dehydration, temperature changes, hypoxia, stress and menstruation.
D. Other symptoms: Short stature, deformed bones, PAIN, PAIN, PAIN, splenic sequestration crisis, cardiomegaly, systolic murmors, CHF, osteomylitis, osteonecrosis, marrow hyperplasia, acute chest syndrome (leading cause of death and hospitalization among SCD patients), cerebrovascular events, impaired psychosocial function, altered inter-intrapersonal relationships, altered sexuality, poor body image, social withdrawal, poor academic functioning, marital problems.

IV. Prevention and Tx:

A. Hydroxyurea (marrow suppression) has been shown to decrease crisis occurrences and pain. Remains unlicensed in most countries due to unknown long term side effects.
B. Being studied: Vascular lubricants, xanthine oxidase inhibitors, nitric oxide enhancers, gardos channel inhibitors, monoclonal AB's, statins, gene therapy.
C. ONLY current available curative therapy is hematopoietic stem cell transplantation which is needed if organ dysfunction occurs.
D. Pain usually managed at home with opioid and non-opioid meds, massage, heating/cooling, electric nerve stimulation.
E. Splenic sequestration: correction of hypovolemia with a transfusion. If it occurs 2-3 yo, spenectomy. Lifetime of AB prophylaxis.
F. Blood Transfusions:
1. increase oxygen-carrying blood
2. improve end-organ perfusion
3. Indications: severe symptoms, splenic sequestration, ACS, acute organ damage, surgery
4. NOT indicated: stable compensated anemia, infections without aplastic crisis, minor surgeries, uncomplicated acute painful crisis.

V. SCD and GA:

A. Dental restorations and simple extractions may be performed on low-risk patients. Moderate risk and high risk must go to OR.
B. NIH recommends simple transfusion prior to all but low risk procedures such as dental, optha etc....
C. Goal of GA management remains meticulous attention to the basic principles of safe anesthesia.

VI. Oral/Dental/Craniofacial Manifestations.

A. Jaundice mucous membranes, glossitis, pallor of tongue, delayed tooth eruption, decreased radiodensity, abnormal radiographic bone presentation, radioluscent teeth, bimaxillary protrusion, flared incisors, tower skull, hair-on-end appearance, granular appearance of skull, mandibular osteomylitis (men),
B. Possible oral pain in the absence of odontogenic pain due to occlusive crisis in the microvasculature of facial muscles.
C. Crisis MAY be precipitated by perio infection, pericoronitis.
D. Possibly a lower caries rate due to long term antibiotic use by those with the disease. Lowered caries rate falls off later in life due to stopped AB use.

VII. Dental Management:

A. HISTORY HISTORY HISTORY
1. Complications, pain episodes, med tx, catheters, blood-born viruses due to transfusions, growth and development.
2. Social and coping issues.
B. Removal of any potential infections must be performed.
C. Painful teeth should be treated seriously.
D. No conclusions have been drawn WRT best pulp therapy.
E. Restorations preferable to extraction.
F. Facial swelling or celulitis may warrant hospitalization.
G. Operative during NON crisis periods.
H. CBC should be done before any invasive dental procedure if the patient is taking HU.
I. No official rec regarding altering Tx due to SCA pts taking bisphosphonates.
J. No evidence supporting using anesthesia withOUT vasoconstrictor.
K. N2O is ok... but care to AVOID hypoxia. Max 50% and pt should breathe 100% O2 for a few minutes following.
L. Need for AB proph remains controversial (some use for endocartditis while others use to prevent systemic infection).
M. Elective surgeries should be avoided.
N. No contra-indications for ortho... unless non-compliance with OH.
O. PHYSICIAN SHOULD BE CONSULTED!!!

Assessment of Article: QUALITY article. Good scientific review, medical considerations, dental considerations, GA considerations!! The ULTIMATE SCA REFERENCE ARTICLE!!!!! Don't think I've ever been this enthusiastic about an article. Don't worry, it won't happen again.

1 comment:

  1. Thank you so much for sharing on this very nice and useful info with us, i am pretty sure your idea is more helpful for me.

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