Med-Surg: Chapter 19: DiGeorge's Syndrome Flashcards
What is DiGeorge’s Syndrome
primary immune dysfunction: T-cell deficiency
- autosomal-dominant (presence of one altered gene) genetic condition that arises from the 22-nd chromosome
- arises spontaneously, present at birth
Autosomal-dominant
means that the presence of only one altered gene is required for the disease to be present
-the child who receives the altered gene from an affected parent will manifest symptoms of the disease
Pathophysiology
arises from a disturbance of the normal embryological development of the pharyngeal pouches occurring between the 6th and 10th weeks of gestation
-Pharyngeal pouches are the embryonic precursors to specific organ systems in the head, neck, and chest (ex: the third and fourth pharyngeal pouches develop into thymus, parathyroid gland and aorta; pulmonary arteries arise from the 6th pharyngeal pouch)
The effects of DiGeorge’s Syndrome Depend on what?
dependent on which pharyngeal pouch is affected but typically involve dysfunction of the thymus gland and parathyroid, facial deformities such as cleft palate, and heart anomalies
Thymus Gland
responsible for T-cell production and differentiation
-thymus dysfunction= T-cell deficiencies
DiGeorge’s Syndrome Easily explained
it is a deficiency in the T-cell
- it is genetic
- depletion of parts of 22nd chromosome
- it happens when there is a disturbance in embryonic development
- the pharyngeal pouch that creates the thymus is disturbed leading to a decrease in T-cell production (the thymus produces T-cells)
- disturbance of the development of the pouches that lead to eventual development of the thymus and parathyroid gland, facial structures, and cardiac structures
T-Cell deficiency Infections
yeast, fungal, protozoan, and viral, such as chickenpox, measles, and rubella
- candida albicans is almost always seen with T-cell deficiencies
- frequent colds or ear infections
General Manifestations
- weakness or tiring easily
- failure to thrive
- failure to gain weight
- difficulty feeding
Respiratory Manifestations
- frequent infections
- SOB
- bluish skin due to low oxygen-rich blood
Other Manifestations
- twitching or spasms around the mouth, hands, arms, or throat
- poor muscle tone
- delayed development of infant milestones
- delayed speech development
- learning delays or difficulties, emotional and behavior problems
- cleft palate or other problems with the palate
- facial features: low-set ears, wide-set eyes, or a narrow groove in the upper lip
Acronym: CATCH 22
- Cardiac abnormality (especially tetralogy of Fallot)
- Abnormal faces
- Thymic aplasia
- Cleft palate
- Hypocalcemia- hypoparathyroidism
Diagnosis
done by genetic testing
-determined with a finding of submicroscopic deletion of chromosome 22 detected by fluorescence in situ hybridization
>fluorescence in situ hybridization uses fluorescence microscopy to find specific features in DNA
Treatment
- calcium supplements to prevent tetany and seizures (can be caused by hypocalcemia from hypoparathyroidism if the parathyroid gland is affected)
- may require treatment of infections
- IVIG to provide short-term passive immunity
Surgical Management: Thymus Tissue Transplantation
- if thymus is absent
- performed within 3 to 6 months of birth, prior to onset of multiple infections
- the tissue is obtained from infants having cardiac surgery; with parents consent tissue is saved from cardiac surgery to use for thymus transplantation
- surgery may also be an option to correct the cardiac defects of the disease (tetralogy of Fallot)
Complications
- may cause problems with the development and function of the brain, resulting in learning, social, developmental, or behavioral problems
- delays in speech development and learning difficulties
- some develop ADHD, autism, or autism-related disorders
- in later life, at risk for depression, anxiety disorders, schizophrenia, and other psychiatric disorders
- due to small thymus, have an increased risk of autoimmune disorders such as rheumatoid arthritis and Grave’s disease
- at risk for graft-versus-host disease; when T-cells in grafted tissue such as transfuse blood attack and destroy the host’s tissues
The Clinical Manifestations are due to what?
the disturbance of normal embryonic development of the pharyngeal pouches that leads to eventual development of the thymus and parathyroid gland, facial structures, and cardiac structures
Nursing Diagnoses
- Risk for complications of opportunistic infections
- Risk for infection r/t compromised host defenses secondary to T-cell immunodeficiency (inadequate function of B cells secondary to T-cell deficiencies)
- High risk for ineffective airway clearance r/t laryngospasm secondary to hypocalcemia
Nursing Interventions: Assessment of Vital Signs
- increased temperature = infection
- respiratory rate may increase with respiratory infections in an effort to increase oxygenation
Nursing Interventions: Lung Sounds
-decreased or adventitious breath sounds may be present with a respiratory infection
Nursing Interventions: Calcium Levels
calcium levels may be decreased b/c of hypoparathyroidism
Nursing Interventions: Assess for Tetany
lack of plasma calcium due to hypoparathyroidism leads to increased neuromuscular activity such as sustained contractions
Nursing Interventions: Monitor WBCs
an increased WBC count = infection
-these values help determine presence of infection and evaluate response to treatment
Nursing Actions
> Administer Calcium Supplements;
-low serum calcium concentration requires calcium supplementation to prevent complications like tetany and bronchospasm
Infection control precautions and standard precautions; hand hygiene:
-prevent infection: hygiene practices is best infection-prevention measure
Strategies for addressing feeding difficulties include modification of spoon placement when eating; treatment of gastroesophageal reflux with acid blockade, prokinetic agents, and postural therapy; and medication to treat GI dysmotility and facilitate bowel evacuation
Coordinate care for cardiac, infectious disease specialists, and speech pathologists
Teachings
> Overview of the disease process
Growth and Developmental Milestones, need for early assessment for learning disabilities, need for ongoing medical care and evaluation
Information and emotional support from networking with other parents of children with similar problems
Evaluating Care Outcomes
well managed child has limited infections, no seizures, and growth and development within normal limits
-accomplished through appropriate treatment with an interprofessional team, adequate monitoring for complications, and support for the caregivers of the child
Assessment Data: Recurrent Infections
-immunodeficiency occurs as a result of thymic hypoplasia, resulting in impaired T-cell production
Assessment Data: Cardiac Abnormality
(especially Tetralogy of Fallot)
- causes cyanosis, heart murmur, difficulty in feeding, failure to gain weight, retarted growth and physical development, dyspnea on exertion, clubbing of the fingers and toes, and polycythemia
- cardiac anomalies are a result of a disturbance of normal embryological development of the pharyngeal pouches–embryonic precursors to specific organ systems in the head, neck, and chest
Assessment Data: Abnormal Faces and Craniofacial Findings
- auricular abnormalities, nasal abnormalities, “hooded eyelids”, increased distance between the eyes (ocular hypertelorism), cleft lip and palate, asymmetric crying faces, and premature fusing of the cranial sutures
- deletion of the portion of chromosome 22 leads to abnormal development of the structures of the face
Assessment Data: Cleft Palate
- may be a structural problem, functional problem, or combination
- b/c of the chromosome deletion, development of the palate is affected in utero
Assessment Data: Hypocalcemia
due to decreased functioning of the parathyroid gland, hypocalcemia is present
Assessment Data: Assessment of Possible feeding problems
-such as gastroesophageal reflux; difficulty sucking/swallowing, advancing feeds, addition of textured foods; and vomiting and constipation
may need NG tube feedings or gastrostomy tube placement
