Engiz Ozlem, Kara Semra, Bagrul Denizhan, Lahr Georgia, Alioglu Bulent, Arikan Inci, Bilge Yıldız Dallar
Department of Pediatric Endocrinology, Ankara Training and Research Hospital, Ankara, Turkey.
J Pediatr Endocrinol Metab. 2012;25(11-12):1205-7. doi: 10.1515/jpem-2012-0129.
Infantile malignant osteopetrosis (IMO; OMIM 259700) is a rare inherited bone disease characterized by reduced or dysregulated activity of osteoclasts, resulting in generalized osteosclerosis. The disease usually presents within the first few months of life with anemia, hepatosplenomegaly, frontal bossing, nystagmus, blindness, deafness, and bone fractures. Children with IMO are at risk of developing hypocalcemia, with attendant tetanic seizures. We report the case of a baby boy who presented with neonatal hypocalcemia. Skeletal radiographs demonstrated sclerotic bones and a dense base of the skull with typical "space alien" face confirming the diagnosis of IMO. Pancytopenia developed at 2 months of age. Visual evoked potential showed severe bilateral optic nerve damage. Genetic mutation study revealed a new mutation in exon 13 of the TCIRG1 gene. Neonatal hypocalcemia can occur as result of IMO, which is easily missed out by clinicians. This causes delay in establishing the diagnosis and starting necessary treatment. Therefore, osteopetrosis should be kept in mind as a rare cause of neonatal hypocalcemia.
婴儿恶性骨硬化症（IMO；OMIM 259700）是一种罕见的遗传性骨病，其特征是破骨细胞活性降低或失调，导致全身性骨硬化。该病通常在出生后的头几个月出现，伴有贫血、肝脾肿大、前额突出、眼球震颤、失明、失聪和骨折。患有IMO的儿童有发生低钙血症的风险，并伴有手足搐搦性惊厥。我们报告了一例出现新生儿低钙血症的男婴病例。骨骼X光片显示骨质硬化以及颅骨底部致密，呈现典型的“外星人”面容，从而确诊为IMO。患儿在2个月大时出现全血细胞减少。视觉诱发电位显示双侧视神经严重受损。基因突变研究显示TCIRG1基因第13外显子有一个新的突变。IMO可导致新生儿低钙血症，临床医生很容易忽略这一点。这会导致诊断延误和必要治疗的延迟。因此，应将骨硬化症视为新生儿低钙血症的一种罕见病因。
