Diamond-Blackfan Anemia
Description
➣Introduction
•Rare congenital red cell aplasia, or inability to produce pure red blood cells.
•exhibits severe anaemia in infancy (90 percent before 12 months), which is typified by reticulocytopenia, macrocytic/normocytic anaemia, and a lack of erythroid precursors in the bone marrow.
•connected to congenital defects (cardiac, thumb, renal, and craniofacial).
•Heritage: approximately 45% autosomal dominant, approximately 55% sporadic, and infrequently autosomal recessive.
~1 in 500,000 live births is the incidence.
● Genetics and Aetiology
•60–70% because to mutations in the ribosomal protein (RP) gene.
• Common: RPL5, RPL11, RPS24, RPS17, RPS26, RPS19 (25% of cases).
Defective ribosome synthesis due to mutations results in ribosomal stress, which in turn triggers p53 activation and erythroid progenitor death.
GATA1 (X-linked) is a non-RP gene mutation that results in impaired erythroid development.
• Between 30 and 35 percent are still genetically unknown.
●Pathophysiology
• Low reticulocyte count in macrocytic normochromic anaemia.
WBC and platelets are typically normal; moderate thrombocytopenia or neutropenia can occur occasionally.
A higher eADA (80–85%), a higher HbF, and a higher EPO.
• Haploinsufficiency: a single faulty RP allele that results in lack of function.
● Clinical Signs and Features
Pallor, lethargy, poor eating, and tachycardia are signs of anaemia.
• Onset: 2 months is the median age of presentation.
Congenital defects (about 50%):
• Craniofacial: snub nose, hypertelorism, and micrognathia.
• Limb: radial ray abnormalities, triphalangeal thumb.
• Cardiac: ASD, VSD, aortic coarctation.
• Renal: agenesis, horseshoe kidney.
• Short height, cleft palate/lip, and growth retardation.
• Eye conditions such as glaucoma, cataracts, and strabismus.
AML, MDS, and solid tumours (osteogenic sarcoma, colorectal cancer) are at risk for malignancy.
●Criteria for Diagnostics (Classical DBA)
•Most important requirement: Age of onset <12 months.
cytopenias other than macrocytic anaemia.
•Reticulocytopenia.
•Normal cellularity of bone marrow without erythroid precursors.
Criteria for support:
•a positive family history or a known mutation in the DBA gene.
eADA and HbF.
•abnormalities that are born.
•additional bone marrow failing disorders were ruled out.
● Examining
•CBC: low reticulocytes, macrocytic anaemia.
•Bone marrow biopsy: no erythroid precursors, normal cellularity.
•Biochemical indicators: ↑ EPO, ↑ HbF, and ↑ eADA.
•Multigene panel genetic testing (RPS19, RPL5, RPL11, etc.).
•Remove acquired factors such as viral indicators and parvovirus B19 serology.
•Other tests include Ig titers, peripheral smears, and immunological phenotyping.
Distinct Diagnosis
• Childhood transient erythroblastopenia (TEC).
• Fanconi anaemia (anomalies with pancytopenia).
•Shwachman-Diamond syndrome (cytopenias + exocrine pancreas).
• Congenital amegakaryocytic thrombocytopenia, TAR syndrome, Dyskeratosis congenita, and Pearson syndrome.
•Aplastic anaemia caused by drugs, viruses, and immunological responses.
Protocol
➣Management/Treatment
• The first line is corticosteroids.
A daily dose of prednisone (≤0.3 mg/kg).
• About 40% react, 35% don't, and many develop a steroid dependence.
• Risks include growth inhibition, bone fragility, and the need for vitamin D, calcium, and bone density monitoring supplements.
•Continuous blood transfusions, if the recipient is intolerant or resistant to steroids.
Aim for Hb ≥8–10 g/dL.
Problem: iron excess → begin iron chelation (desferrioxamine, deferasirox).
●Hematopoietic Stem Cell Transplant (HSCT) – only curative option.
• Best results if the sibling donor is HLA-matched and under 10 years old.
• Risks include infections and graft-versus-host disease.
• Experimental gene therapy
particularly in mutations of RPS19.
• Trials on viral vector gene substitution show promise.
Supportive Care
• Consistent monitoring (marrow biopsy, ferritin, CBC).
• Genetic counselling for families with a 50% chance of autosomal dominant inheritance.
social and psychological assistance as a result of long-term sickness.
➣ Nursing Interventions with a Problem Focus
Issue 1: Anemia-related Risk of Ineffective Tissue Perfusion
• Intervention: Keep an eye on blood pressure, heart rate, and breathing rate as well as hypoxic symptoms such weariness, pallor, and cyanosis.
• Intervention: Give transfusions of red blood cells as directed and keep an eye out for transfusion reactions.
•Intervention: Promote relaxation, group nursing exercises, and impart energy-saving techniques.
Issue 2: • Immunosuppressive infection risk (due to steroid treatment or bone marrow malfunction) • Intervention: Regularly check for infection symptoms, including fever.
•Intervention: Adopt infection control procedures and maintain stringent hand hygiene.
Intervention: Inform the patient and their family about early infection detection and when to get medical attention.
Issue 3: • Iron overload risk associated with long-term transfusions
• Intervention: As part of routine laboratory testing, check serum ferritin and iron levels.
•Intervention: As directed, prepare and give iron chelation treatment while keeping an eye out for any adverse medication reactions.
The fourth issue is the possibility of fluid volume imbalance brought on by transfusion or steroid medication. The solution is to keep an eye on daily weight, intake and output, and look for symptoms of fluid overload, such as oedema.
• Intervention: Inform family members of the value of consuming the right amount of fluids.
Issue 4: The possibility of delayed growth and development as a result of chronic sickness and inadequate oxygenation
•Intervention: Work with dietitians to make sure you're getting enough calories and nutrients.
I• Intervention: Keep an eye on developmental milestones and growth metrics.
Intervention: Promote involvement in activities that are suitable for the child's age and, if necessary, refer the child to developmental specialists.
●Problem 5:
•Impaired Family Coping related to chronic disease management
•Intervention: Offer resources for counselling as well as emotional support.
•Intervention: Inform parents and carers about the illness, its treatment options, and the need for at-home care.
Intervention: Make connections between families and support groups and organise multidisciplinary care.
Notes
For more details visit https://www.ncbi.nlm.nih.gov/books/NBK545302/
