This book we use for this class:
ANATOMY AND PHYSIOLOGY; THE UNITY OF FORM AND FUNCTION (LL)
Scenario/Summary
In this case
study, we look at the clinical implications of what happens to a client when
one of a cell’s “tiny organ” organelles fails to function properly.
In particular, we will use a lysosomal storage disease to demonstrate this.
Mrs. Anderson brings her 9-month-old
daughter, Emily, to the pediatric clinic for a routine check-up. During the
examination, the nurse practitioner notices that Emily is not reaching typical
developmental milestones. Mrs. Anderson mentions that she has noticed a loss of
formerly acquired skills, such as the ability to track objects with her eyes
and respond to her name.
Upon further inquiry, Mrs. Anderson
discloses that she and her husband are carriers of Tay-Sachs disease, a genetic
disorder that runs in their Ashkenazi Jewish heritage. The nurse practitioner
decides to conduct a thorough assessment, including a neurological examination.
During the examination, Emily exhibits
decreased muscle tone, poor head control, and a lack of response to visual and
auditory stimuli. The nurse also observes a cherry-red spot on the retina upon
fundoscopic examination. Given Emily’s clinical presentation and the family
history, the nurse suspects Tay-Sachs disease.
Additional diagnostic procedures, such
as enzyme assays, validate the presence of hexosaminidase A deficiency, thereby
establishing the diagnosis of Tay-Sachs disease. The nurse discusses the
prognosis and challenges associated with Tay-Sachs with Mrs. Anderson,
providing emotional support and referring the family to a genetic counselor for
further guidance.
Over subsequent visits, the nurse
collaborates with the healthcare team to implement a comprehensive care plan
that focuses on symptom management, supportive therapies, and anticipatory
guidance for the family. The interdisciplinary team works together to optimize
Emily’s quality of life while addressing the complex medical and emotional
aspects of Tay-Sachs disease.
KEY CHARACTERISTICS OF THIS
CONDITION
· Developmental
delay: clients may not reach developmental
milestones.
· Fundoscopic
examination shows a characteristic cherry red spot on the
macule: due to the deposition of GM2 ganglioside. Gangliosides are a
type of glycosphingolipid, which means they consist of a lipid
(fatty acid) portion and a carbohydrate (sugar) portion. GM2 gangliosides are
complex glycosphingolipids that are an integral part of cell membranes,
particularly in nervous tissue.
· Cause: Hexosaminidase
A gene (HEXA) gene mutation.
· Consequence: Hexosaminidase
A enzyme (HEX A) is required to degrade GM2 ganglioside; without the HEX A
enzyme, GM2 ganglioside accumulates in the lysosomes of brain and nerve cells.
· Inheritance
pattern: autosomal recessive
Deliverables
Please
address the following questions in complete sentences.
1. What is the normal function of Lysosomes?
2. What are the monomers of the Hexosaminidase A
enzyme?
3. What is the composition of a cell’s plasma
membrane?
4. List all the non-membrane-bound and all the
membrane-bound cellular organelles in a eukaryotic cell.
5. A nurse is caring for a
6-month-old infant who has been diagnosed with Tay-Sachs disease. The parents
express concern about the child’s developmental milestones. Which of the
following statements by the nurse is most appropriate?
a. “Your child’s development may be delayed,
but interventions can help improve outcomes.”
b. “Tay-Sachs disease
typically does not affect developmental milestones in the first year of
life.”
c. “Your child’s development
is likely to progress normally, as Tay-Sachs primarily affects motor
function.”
d. “There’s no need to worry
about developmental delays in Tay-Sachs disease; it primarily affects cognitive
function.”
