Contributions
Abstract: PB1834
Type: Publication Only
Background
Pure red cell anemia is characterized by normochrome normocytic anemia with severe reticulocytopenia and marked decrease or absence in red cell lineage in bone marrow. We herein present a child with congenital pure red cell anemia diagnosed as ADA2 enzyme deficiency to emphasize this rare etiology of pure red cell anemia.
Aims
A 40 day old boy was admitted to our hospital with pallor. On physical examination, there was no hepatosplenomegaly or any stigmates. His laboratory work up showed severe anemia, hgb:2 gr/dl; htc:%5.8; wbc:9750 /mm3; neu:1800/mm3; plt:690 000/mm3; MCV:89 fL; LDH:360 U/L. Electrolytes, kidney function tests, and liver function tests were normal. Direct coombs test was negative, reticulocyte count was low (0.2%). On blood smear, erythrocytes were normal in shape and size with no signs of hemolysis. On follow up he was transfusion dependant monthly. Bone marrow aspiration showed decreased erythrocyte progenitor cells. HbF was 5.8%. Viral serology including Parvovirus was negative. Vitamin B12 and folate levels were normal, erythropoetin was 39.9 mU/ml (increased). The diagnosis of pure red cell aplasia was established. He also had a history of recurrent infections and his immunoglobulins were low. The genetic analysis for DBA was negative.
Methods
Whole exome sequencing, showed CECR1 mutation causing ADA-2 enzyme deficiency. His parents were silent carriers. The patient’s follow up continues in our outpatient clinic, he receives erythrocte tranfusion and intravenous human immunglobulin monthly.
Results
CECR1 gene is responsible for the synthesis of ADA 2 enzyme which is the major extracellular adenosine deaminase and functions as a growth factor. It was first identified in 2014 in patients with poliarteritis nodosa by exome sequencing and is responsible for a spectrum of autoinflammatory symptoms from vasculitis to thromboembolic events. ADA- 2 enzyme deficiency has been described in around 100 patients until now. Most of the patients had inflammatory symptoms like vasculopathy, lacunar strokes, hepatosplenomegaly or livedo reticularis. Hematologic manifestations were poorly described and unexpected without the inflammatory symptoms or immunodeficiency. In 2016, 5 patients from Israel were reported with hematological manifestations, 2 siblings had congenital pure red cell anemia without any vasculopathy.
Conclusion
Together with other case reports, our patient represents a new phenotype of this mutation and causes the need for evaluating the functions of ADA 2 in bone marrow.
Session topic: 12. Bone marrow failure syndromes incl. PNH - Clinical
Keyword(s): Anemia, Bone Marrow Failure, Diamond-Blackfan anemia
Abstract: PB1834
Type: Publication Only
Background
Pure red cell anemia is characterized by normochrome normocytic anemia with severe reticulocytopenia and marked decrease or absence in red cell lineage in bone marrow. We herein present a child with congenital pure red cell anemia diagnosed as ADA2 enzyme deficiency to emphasize this rare etiology of pure red cell anemia.
Aims
A 40 day old boy was admitted to our hospital with pallor. On physical examination, there was no hepatosplenomegaly or any stigmates. His laboratory work up showed severe anemia, hgb:2 gr/dl; htc:%5.8; wbc:9750 /mm3; neu:1800/mm3; plt:690 000/mm3; MCV:89 fL; LDH:360 U/L. Electrolytes, kidney function tests, and liver function tests were normal. Direct coombs test was negative, reticulocyte count was low (0.2%). On blood smear, erythrocytes were normal in shape and size with no signs of hemolysis. On follow up he was transfusion dependant monthly. Bone marrow aspiration showed decreased erythrocyte progenitor cells. HbF was 5.8%. Viral serology including Parvovirus was negative. Vitamin B12 and folate levels were normal, erythropoetin was 39.9 mU/ml (increased). The diagnosis of pure red cell aplasia was established. He also had a history of recurrent infections and his immunoglobulins were low. The genetic analysis for DBA was negative.
Methods
Whole exome sequencing, showed CECR1 mutation causing ADA-2 enzyme deficiency. His parents were silent carriers. The patient’s follow up continues in our outpatient clinic, he receives erythrocte tranfusion and intravenous human immunglobulin monthly.
Results
CECR1 gene is responsible for the synthesis of ADA 2 enzyme which is the major extracellular adenosine deaminase and functions as a growth factor. It was first identified in 2014 in patients with poliarteritis nodosa by exome sequencing and is responsible for a spectrum of autoinflammatory symptoms from vasculitis to thromboembolic events. ADA- 2 enzyme deficiency has been described in around 100 patients until now. Most of the patients had inflammatory symptoms like vasculopathy, lacunar strokes, hepatosplenomegaly or livedo reticularis. Hematologic manifestations were poorly described and unexpected without the inflammatory symptoms or immunodeficiency. In 2016, 5 patients from Israel were reported with hematological manifestations, 2 siblings had congenital pure red cell anemia without any vasculopathy.
Conclusion
Together with other case reports, our patient represents a new phenotype of this mutation and causes the need for evaluating the functions of ADA 2 in bone marrow.
Session topic: 12. Bone marrow failure syndromes incl. PNH - Clinical
Keyword(s): Anemia, Bone Marrow Failure, Diamond-Blackfan anemia