Osteogenesis imperfecta type VIII: highlighting the need for genetic testing.

Area of Science:

• Genetics
• Pediatrics
• Orthopedics

Background:

• Osteogenesis Imperfecta (OI) is a group of genetic disorders characterized by fragile bones.
• OI type VIII is a severe, autosomal-recessive form typically associated with blue sclerae.
• This report focuses on the first documented case of OI type VIII in Tanzania.

Observation:

• A neonate presented with shortened limb girdles, macrocephaly, and multiple long bone fractures.
• Clinical diagnosis suggested OI or metaphysial dysplasia.
• Plain X-ray confirmed multiple fractures, but sclerae were white, atypical for OI type VIII.

Findings:

• Genetic testing revealed mutations in the prolyl 3-hydroxylase 1 (P3HI) gene.
• A novel variant (NM_001243246.1:c.1095C>G p) was identified, confirming a severe, fatal autosomal-recessive OI type VIII.
• This variant presented with white sclerae, differing from typical presentations.

Implications:

• This case underscores the need for genetic testing in diagnosing severe OI, especially when clinical features are atypical.
• It expands the known spectrum of OI type VIII phenotypes.
• Highlights the importance of genetic diagnostics in lower-middle income countries.