Megaloblastic anemia is a hematological disorder in which the bone marrow produces abnormally large nucleated cells, including immature erythrocytes, superlobulated polymorphic leukocytes and large platelets. At the cellular level, megaloblastic anemia 1 (MGA1), originally named Imerslund-Grasbeck syndrome (IGS), is caused by intestinal malabsorption of vitamin B12 (cobalamin) due to a defect in the vitamin B12/gastric intrinsic factor (GIF) complex receptor. Clinically, IGS is characterized by relatively early childhood onset (before age 5 years), failure to thrive, infections, low level of vitamin B12 in serum, mild and innocuous proteinuria, and variable neurological symptoms such as peripheral neuropathy, cognitive problems, and dementia.
For the first time from Bahrain, Al-Ajmi et al, 2003, described a rare case of pernicious anemia (PA) in a young female.
Ismail et al, 1997, reported seven patients in two unrelated consanguineous Bedouin families with Grasbeck-Imerslund syndrome. In Family one, three affected male sibs, had a deceased brother, who died of severe anemia, and seven apparently healthy sisters, suggesting an X-linked mode of inheritance. Family two had four affected and four healthy sibs alluding to a possible autosomal recessive mode of inheritance.
Tanner et al, 2004, studied two unrelated Kuwaiti families with a total of 7 patients affected by megaloblastic anemia. No mutations were uncovered in the CUBN or AMN genes.
Rossler et al, 2003, described four children from a Lebanese family with megaloblastic anemia. The patients had a late onset of disease and no proteinuria.
Abdelaal and Ahmed, 1991, reported a Saudi family affected by megaloblastic anemia. The patients included an 18 year old male proband, his 15 year old sibling and 6 year old first cousin.
Al Essa et al, 1998, described two Saudi sisters with this disorder. In children, early anemia usually leads to the diagnosis. In this case, however, the presence of hemoglobinopathy that required frequent transfusions masked the usual macrocytosis, and the older sister was not diagnosed until the age of 12 years when neurologic changes became apparent. Dementia and paralysis responded remarkably to treatment, despite the late diagnosis.
Bulut et al, 2012, described a case of Imersland-Grasbeck Syndrome in a 17-month-old Saudi Arabian boy.