Table 1 Clinical features of the presented patients compared to the typical iMMA phenotypes
Cbl-nonresponsive mut0, CblB | Cbl-responsive mut-, CblA | Patient 1 | Patient 2 | |
|---|---|---|---|---|
Neonatal manifestation | yes | yes | yes, 3rdday of life | yes, 4thday of life |
Severe metabolic acidosis | yes | not typical | yes | yes |
Severe hyperammonemia (normal range 0-60 μmol/L) | yes | not typical | yes, 1,094 | yes, 1,600 |
MMA in urine (normal range < 2.5 μmol/mmol creatinine) | 1,000-10,000 | 10-hundreds | 32,900 | 47,686 |
Severe metabolic crises despite therapy | yes | no | yes | no |
Response to the Cbl treatment | no | yes | partial, better to OH-Cbl | yes, better to OH-Cbl |
Patient´s working diagnosis | mut0 | CblA, mut- | ||
Patient´s confirmed genotype | MMAB: c.[556C>T];[556C>T] p.[(Arg186Trp)];[(Arg186Trp)] | MMAA: c.[266T>C];[266T>C] p.[(Leu89Pro)];[(Leu89Pro)] |