Could Cobalamin Deficiency Mimic a Clonal Aberration Cytogenetic? a Case Report

A 32 years old female patient presented to our service complaining asthenia, apathy and loss of her power to work. It was observed, by laboratory test, pancytopenia (Hb: 6.0 g/dL; WBC: 2,100/mm³, platelets 95,000/mm³, Reticulocytes 0.8%) associated with marked elevation of LDH 1,800 U/L (normal range: 240 – 480U/L). Bone marrow aspirate demonstrated morphologic features of megaloblastic anemia. Moreover, low serum concentration of vitamin B12 < 150pg/mL (normal range: 200 – 95-pg/mL), Folic acid 15,9ng/mL (normal range: 3 – 17 ng/mL) confirmed Megaloblastic anemia by cobalamin deficiency. It was not evidenced gastritis. It was initiated the treatment with vitamin B12. However, in the next clinical attendance it was observed an unexpected cytogenetic result: 46,XX,del(9)(q13q22)[3]/76~78,XXX,+1,+3,+4,+9,+11,+12,+17,+20,+21[cp3]/46,XX[34].

It was interpreted that del(9)(q13q22)[3] could be a clonal cytogenetics aberration and the others data due to defects in synthesis of DNA by cobalamin deficiency. It was important, because in diagnosis of Megaloblastic anemia frequently it is not included cytogenetic analysis of bone marrow cells and a new cytogenetic analysis has become necessary due to this data. After two months, a complete hematological recovery was achieved and six months later, bone marrow aspirate and cytogenetic analisys were repeated. Normal morphologic bone marrow cells and normal cytogenetic: 46,XX[20] were evidenced. Therefore, it was really hard to conclude this case. First, cobalamin deficiency could promote this clonal deletion or, as a second hypothesis, a clonal cytogenetic with low proliferative rate was selected due to inefficient hematopoiesis, by vitamin B12 deficiency, and after the recovery of the hematopoiesis, this clonal was suppressed.