[TRMU MUTATIONS - REVERSIBLE INFANTILE LIVER FAILURE OR MULTISYSTEM DISORDER?].

INTRODUCTION

Bi-allelic mutations in the TRMU gene cause reversible infantile liver failure. Little is known about extra-hepatic manifestations in these patients.

BACKGROUND

Two infants, aged 4 and 5 months, presented with progressive life threatening liver failure, characterized by lactic acidosis, highly elevated alpha-fetoprotein and recurrent hypoglycemia. Both showed significant extra-hepatic findings, including: hypothyroidism, macrocytic anemia and microcephaly. Both were of Jewish Yemenite descent and homozygous for Y77H mutation in the TRMU gene.

CONCLUSIONS

TRMU bi-allelic mutations cause severe life-threatening liver failure. Extra-hepatic involvement is common and should be evaluated. Spontaneous resolution and recovery occurs in most patients with a remarkably good long-term prognosis. Liver failure in a Jewish-Yemenite infant should prompt early genetic testing for TRMU Y77H mutation. Pediatricians should be aware of this disease and the common mutation in Israel.

DISCUSSION

Nineteen additional patients were described in the literature, of whom 13 were from Israel; 6/19 (31%) manifested extra-hepatic involvement, namely: myopathic weakness, cardiomyopathy, renomegaly and proteinuria, bulbar dysfunction, cerebral white matter changes and abnormal growth including microcephaly. Mortality was 24% (5/21). Survivors (16/21, 76%) showed complete recovery and resolution of clinical, laboratory and histologic abnormalities. Most Israeli patients (10/15) were of Jewish-Yemenite ancestry. Homozygous Y77H genotype was exclusive to this patient subgroup and was associated with a 100% survival and recovery rate.