Malignant infantile osteopetrosis: A rare cause of refractory hypocalcemia

• Main Authors: Niraj Kumar Dipak (Author), Nadia Shagufta (Author)
• Format: Book
• Published: Wolters Kluwer Medknow Publications, 2023-01-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

Background: Infantile malignant osteopetrosis (IMO) is a rare autosomal recessive disease characterized by a higher bone density in bone marrow caused by the dysfunction of bone resorption. Clinical Description: A 2-month-old baby boy presented with features of lower respiratory tract infection, along with a swollen right upper arm due to fracture of humerus, along with signs of bicytopenia and hepatosplenomegaly. He had a history of hypocalcemic seizures at 8th day of life. Management and Outcome: Current hospitalization revealed refractory hypocalcemia and hypophosphatemia with normal to increased Vitamin D and parathormone levels and increased density of bone. Hypocalcemia was particularly refractory in nature needing multiple intravenous calcium corrections. Whole exome sequencing detected compound heterozygous variants in the T-cell immune regulator 1 pathogenic gene of IMO. Simultaneously, a heterozygous nonsense variation in exon 4 of the CHRNA4 gene was detected causing nocturnal frontal lobe epilepsy. As the infant had evidence of bone marrow failure, he was considered and referred for hematopoietic stem cell transplantation. Conclusion: Neonatal and early infantile hypocalcemia are commonly seen by pediatricians, but an etiology of IMO is rarely considered. The presence of fracture of long bones with cytopenias and hepatosplenomegaly in a young infant with recurrent hypocalcemia, without Vitamin D deficiency, should raise suspicion of this disorder and genetic analysis should be carried out for the same.

Item Description

2772-5170
2772-5189
10.4103/ipcares.ipcares_70_23