Quick Reference Guide for Clinicians: Sickle Cell Disease: Comprehensive Screening and Management in Newborns and Infants

16 Pages·1993·0.79 MB·English

Quick Reference Guide for Clinicians
Number 6
Sickle Cell Disease:
Comprehensive Screening
and Management in
Newborns and Infants
■ Screening
■ Laboratory Methods
■ Diagnosis
■ Medical Management
■ Education and Counseling
U.S. Department of Health and Human Services
Public Health Service
Agency for Health Care Policy and Research
Attention clinicians: No. 93-0562). To receive
additional copies of the Clinical
The Clinical Practice Guideline
Practice Guideline, which
on which this Quick Reference
includes this Quick Reference
Guide for Clinicians is based was
Guide (AHCPR Publication No.
developed by an interdisciplinary,
93-0563), and a Parent’s Guide
private-sector panel comprising
(AHCPR Publication No.
health care professionals and
93-0564), call toll free
consumer representatives. Panel
800-358-9295 (from outside the
members were:
continental United States only,
Jeanne A. Smith, MD, MPH call 301-495-3453) or write the
(Co-Chair) AHCPR Publications
Clearinghouse, PO. Box 8547,
Thomas R. Kinney, MD
Silver Spring, MD 20907.
(Co-Chair)
AHCPR invites comments
Beverly A. Ames and suggestions from users for
consideration in developing and
Kwame Anyane-Yeboa, MD
updating future guidelines.
Samuel Charache, MD Please send written comments to
Director, Office of the Forum for
Melvin Gerald, MD, MPH
Quality and Effectiveness in
Serena Gilbert, MSW Health Care, AHCPR,
Executive Office Center,
David Phoenix, DrPH
Suite 401, 2101 East Jefferson
Elliot Vichinsky, MD Street, Rockville, MD 20852.
Ruby LaVerne Wesley, PhD, RN
Doris L. Wethers, MD
Charles Whitten, MD Note: This Quick Reference
Guide for Clinicians contains
Iola Williams, RN, PNP
excerpts from the Clinical
For a description of the guideline Practice Guideline, but users
development process and infor¬ should not rely on these excerpts
mation about the sponsoring alone. Clinicians should refer to
agency (Agency for Health Care the complete Clinical Practice
Policy and Research), see the Guideline for more detailed anal¬
Clinical Practice Guideline for ysis and discussion of the avail¬
Sickle Cell Disease: Screening, able research, critical evaluation
Diagnosis, Management, and of the assumptions and knowl¬
Counseling in Newborns and edge of the field, health care deci¬
Infants (AHCPR Publication sion making, and references.
Sickle Cell Disease:
Comprehensive Screening
and Management in
Newborns and Infants
Purpose and Scope
Sickle cell disease comprises a abnormally shaped red cells.
group of genetic disorders charac¬ Complications include painful
terized by the inheritance of sickle episodes involving soft tissues and
hemoglobin (Hb S) from both bones, acute chest syndrome,
parents or Hb S from one parent priapism, cerebral vascular acci¬
and a gene for an abnormal hemo¬ dents, and both splenic and renal
globin or beta-thalassemia from the dysfunction. Common causes of
other parent. The presence of Hb S mortality among children with
can cause red blood cells to change sickle cell disease include bacterial
from their usual biconcave disc infections, splenic sequestration
shape to a crescent or sickle shape crisis, and acute chest syndrome.
during deoxygenation. Upon
Sickle cell disease affects more
reoxygenation, the red cell initially
than 50,000 Americans, primarily
resumes a normal configuration, but
those of African heritage, but also
after repeated cycles of “sickling and
those of Mediterranean, Caribbean,
unsickling,” the erythrocyte is
South and Central American,
damaged permanently and hemo-
Arabian, or East Indian ancestry. It
lyzes. This hemolysis is responsible
is estimated that 8 percent of the
for the anemia that is a hallmark of
African American population
sickle cell disease. The following
carries the sickle cell trait, and
table includes the most common
approximately 1 African-American
types of sickle cell disease.
child in every 375 is affected by
Acute and chronic tissue injury sickle cell disease. Thus, it is among
can occur when blood flow through the most prevalent of genetic
the vessels is obstructed by the diseases in the United States.
Types of Sickle Cell Disease
Sickle cell anemia S-O Arab
Hemoglobin SC disease S-Lepore
Sickle beta-thalassemia S-E disease
S-D Punjab
1
This Quick Reference Guide
Screening
contains excerpts from the Clinical
Practice Guideline on Sickle Cell
Neonatal screening programs for
Disease: Screening, Diagnosis,
sickle cell disease should be
Management, and Counseling in
comprehensive. Such programs
Newborns and Infants. Clinicians
require the integration of several
should not rely on this summary
components, including administra¬
alone but should refer to the Clini¬
tion, laboratory, medical manage¬
cal Practice Guideline for a more
ment, and education/counseling.
complete discussion of issues and
recommendations.
The algorithm, found on pages 8
Administration
and 9 of this Quick Reference
Guide, shows the sequence of
events related to sickle cell screen¬ The administrative component
ing, diagnosis, medical manage¬ should oversee the entire program,
ment, and counseling in newborns monitoring the efficacy of the
and infants. This Quick Reference screening initiative, the quality and
Guide provides information about accuracy of laboratory testing, the
the events listed in the algorithm. diligence of medical followup, and
the activities of the education and
counseling program.
Guiding Principles
The administrative group should
include public health officials;
■ All infants should be screened
geneticists; representatives from the
for sickle cell disease, regardless
laboratory; staff from the education
of race or ethnic background.
and counseling program; physicians
■ Sickle cell screening must be done
knowledgeable about sickle cell
by accurate laboratory methods.
disorders, thalassemia, and other
■ Physicians must establish a hemoglobinopathies; and when
definitive diagnosis in a timely possible, representatives of commu¬
fashion for infants with a posi¬ nity-based sickle cell organizations.
tive screening test.
■ Affected infants and parents
Population To Be
must have access to comprehen¬
sive health care services, includ¬ Screened
ing education and decision¬
making counseling. Universal screening is the only way
to ensure that all infants benefit
■ Neonatal sickle cell screening
equally and that no infant is
programs also provide an oppor¬
subjected to the risk of early death
tunity to identify other members
from sickle cell disease because the
of the family with sickle cell trait
screening test was not performed.
and other abnormal hemoglobins.
When these individuals are found, Screening programs targeting a
clinicians should offer them specific racial or ethnic group will
education and genetic counseling. not identify all infants with sickle
2
cell disease, because it is impossible this method requires consider¬
to define reliably an individual’s able expertise and is costlier than
racial or ethnic background by phys¬ the more established methods.
ical appearance, surname, or self-
■ The methods chosen for screen¬
report.
ing newborns should have high
rates of sensitivity and specificity
for identification of newborns
Laboratory Issues
with sickle cell disease and other
clinically important
Blood Samples hemoglobinopathies.
■ To obtain reliable results, blood
samples for sickle cell screening
must be collected prior to trans¬
fusion.
■ Blood samples collected from
Note: Neither the sodium
the infant by heel stick onto
metabisulfite sickle cell
filter paper are preferred for
preparation nor solubility
sickle cell screening because
tests employing a concen¬
shipment to the laboratory is
trated phosphate buffer and
easy. This collection method is
sodium dithionate should be
currently employed for other
used for newborn screening
screening programs including
or confirmation of Hb S in
those for phenylketonuria,
early infancy.
hypothyroidism, and galac¬
tosemia.
■ Liquid blood samples, obtained
from the umbilical cord or
directly from the infant, are
acceptable alternatives but are
Laboratory
more expensive and difficult to
Qualifications
transport to the screening labo¬
ratory.
All testing should be done by labo¬
Testing Methods ratories that are licensed by their
respective States or territories and
■ Hemoglobin electrophoresis, that meet the requirements of the
isoelectric focusing, and high Clinical Laboratory Improvement
performance liquid chromatog¬ Act of 1988 (CLIA 88).
raphy are all proven, reliable,
Laboratory testing should be linked
and accurate methods for defin¬
to other existing newborn screening
ing an infant’s hemoglobin
programs within the jurisdiction to
phenotype.
facilitate specimen collection, iden¬
■ Globin DNA analysis is an addi¬ tification, handling, and result
tional testing method, though reporting.
3
Quality Assurance and Medical Management
Quality Control
Responsibilities of Health
The screening program must moni¬ Care Providers
tor all aspects of the screening
process from sample collection to ■ Assignment of definitive diagno¬
confirmation of diagnosis and track¬ sis is the responsibility of the
ing of infants to ensure that those infant’s physician. Physicians
with positive screening tests are unfamiliar with diagnostic crite¬
retested and that infants with ria should seek consultation
confirmed diagnoses are entered from hematologists knowledge¬
into comprehensive care. able about sickle cell disease,
thalassemia, and other hemo¬
Laboratories must participate in a
globinopathies.
proficiency testing program and,
when feasible, should retest at least ■ When a newborn tests positively
a sample of all newborns screened to for sickle cell disease or other
determine the sensitivity and speci¬ hemoglobinopathy, health care
ficity of its screening methodology. providers should immediately
contact the parents to inform
them of the need for the infant’s
immediate evaluation and
Reporting of
retesting.
Screening Results
■ Since newborn screening does
not establish a definitive diagno¬
Screening laboratories should main¬
sis, a second sample must be
tain accurate records and are respon¬
collected from the infant. In addi¬
sible for promptly communicating
tion to defining the hemoglobin
test results to the infant’s health care
phenotype, the second specimen
provider of record, hospital of birth,
should be used to determine a
the screening programs administra¬
complete blood count with red
tive component, and when permitted
cell indices and assessment of red
by law, to the infant’s mother.
cell morphology.
Reporting of the screening result
■ Characterization of the
should include the hemoglobin
hemoglobin phenotype of the
phenotype and mention the diagnos¬
parents can be extremely help¬
tic possibilities associated with the
ful. The clinician must be aware
phenotype. Reports to health care
that testing of the parents may
providers and mothers should list
disclose nonpaternity.
sources of additional information.
The report must clearly indicate the ■ DNA analysis of the infant’s
likelihood that the infant may have beta (B) globin gene complex
sickle cell disease and stress the also may be used to establish a
urgency for immediate followup. definitive diagnosis.
■ Physicians and other health care
providers must be aware that
4
any sign of illness in an infant months and should receive poly¬
with sickle cell disease is a valent pneumococcal vaccine at
potential medical emergency. age 2 years. Infants also should
Complications of sickle cell be immunized against hepatitis
disease include, but are not B virus.
limited to sepsis, acute chest
■ Diet should be monitored to
syndrome, splenic sequestration
ensure that the child with sickle
crisis, aplastic crisis, stroke and
cell disease is receiving all neces¬
hand-and-foot syndrome, and
sary nutrients and adequate
painful episodes.
calories. Multivitamins during
■ The physician or other health the first 2 years of life may be
care provider is responsible for appropriate.
providing or arranging for appro¬
priate education and genetic Parental Instruction
counseling for the parents.
■ Health care providers must
stress to parents the importance
Prophylactic penicillin
of twice-daily doses of prophy¬
■ Infants with documented or lactic penicillin as an effective
suspected sickle cell anemia or measure to reduce both morbid¬
Hb S B°-thalassemia should be ity and mortality from pneumo¬
started on twice-daily oral coccal infections in infants with
prophylactic penicillin as soon as sickle cell anemia and HB S
possible, but no later than 2 beta°-thalassemia.
months of age.
■ Parents of infants with sickle cell
■ In those instances where the disease should be instructed in
definitive diagnosis cannot be all aspects of routine child care
determined, an infant with the and should be able to determine
FS phenotype should be main¬ accurately the infant’s tempera¬
tained on prophylactic ture. They must be able to recog¬
penicillin until the definitive nize complications of sickle cell
diagnosis is established. disease, including the signs and
symptoms of fever, pallor, and
■ Prophylactic penicillin should be
respiratory distress. Parents
continued until at least 5 years
should be instructed on palpa¬
of age.
tion of the infant’s spleen and be
Well-Baby Care taught to recognize splenic
enlargement.
■ Infants with sickle cell disease
should receive standard well ■ The parents must understand the
baby care. In addition to immu¬ importance of prompt assess¬
nizations against polio, diphthe¬ ment of the infant by a physician
ria, tetanus, measles, mumps, knowledgeable about sickle cell
and rubella, children with sickle disease when there is fever,
cell disease should be immu¬ pallor, unexplained irritability,
nized against Haemophilus diarrhea, vomiting, or other
influenzae beginning at age 2 signs of illness.
5
Access to care Education
■ Acutely ill infants with sickle cell ■ Sickle cell education should
disease should have access to include an explanation of the
tertiary care facilities that are differences between the disease
staffed by pediatricians and and the trait, prevalence of
pediatric surgeons knowledge¬ sickle cell trait and anemia in the
able about sickle cell disease. U.S. population, the health
status of persons with sickle cell
■ These facilities should include a
trait, and the risks of having a
sophisticated blood bank and
child with sickle cell disease for
clinical laboratories, as well as
persons with the trait.
modern imaging equipment.
■ Information should be presented
clearly using interactive tech¬
niques, appropriate graphics,
Education and
and plain language. Easily
Counseling
understandable literature should
be given to the parents to take
Principles home at the end of the education
session.
■ A neonatal sickle cell screening
program not only identifies ■ Parents should be offered the
infants with sickle cell disease, opportunity to be tested if they
but also opens a “genetic so desire.
window,” which can result in the
■ All adults testing positive for
detection of other family
either Hb S, 6°-thalassemia trait,
members with sickle cell trait,
or a variant hemoglobin and
sickle cell disease, or other
those who have partners with
hemoglobin diseases and
either of these conditions also
heterozygotes for hemoglobin
should be offered decision¬
variants.
making counseling.
■ Screening programs have an
■ At a minimum, sickle cell educa¬
obligation to inform parents
tors should have a high school
regarding their infant’s result
diploma and a certificate of
and to offer related education
competency in sickle cell educa¬
and counseling.
tion. The certifying process
■ Screening provides an invaluable should be approved by the
opportunity to educate and administrative component of the
counsel families. screening program and include
successful completion of an
examination that assesses knowl¬
edge of the material.
■ The educator’s skills should be
evaluated periodically, and their
sickle cell knowledge base
should be updated annually.
6
Decision-Making
Conclusion
Counseling
■ Decision-making counseling
Although the prevalence of
should provide objective infor¬
hemoglobin disorders differs among
mation about sickle cell disease
racial and ethnic groups, it is impos¬
and trait to individuals who are at
sible to define reliably an individu¬
risk of having a child with sickle
als’ race or ethnicity in a heteroge¬
cell disease. It should include
neous society like the United States.
specific information on the natu¬
It is therefore recommended that
ral history of the type of sickle
screening programs provide equal
cell disease that may affect the
access to health care by screening
individual’s offspring and the
all infants for sickle cell disease and
resources that may be required to
other hemoglobinopathies.
care for the child. This empowers
the prospective parents to make Screening programs should reduce
informed decisions. costs through cooperative arrange¬
ments negotiated with other
■ Decision-making counseling
programs or with institutional or
must always be objective and
commercial laboratories to obtain
should not offer specific recom¬
the lowest cost per test for universal
mendations. The counseling
sickle cell screening.
atmosphere must be private and
conducive to a free exchange of
information. Algorithm
■ Counseling should be done by
professionals with backgrounds The algorithm on pages 8 and 9
and training in guidance and presents a visual display of the orga¬
counseling, such as physicians, nization, procedural flow, and deci¬
clinical geneticists, genetic asso¬ sion points in identifying and care-
ciates, medical social workers, ing for newborns and infants with
and nurses. sickle cell disease, sickle cell trait,
and other hemoglobinopathies and
■ Quality assurance is an essential
educating and counseling their
component of a genetic counsel¬
parents. Numbers in the algorithm
ing program.
refer to the annotations that follow.
Note: All chapter references are to
the complete Clinical Practice
Guideline, Sickle Cell Disease:
Screening, Diagnosis, Management,
and Counseling in Newborns and
Infants.
7
Detection and Management of Sickle Cell Disease:
An Algorithm
1
8