Unawareness; The Reason of Delayed Diagnosis of Niemann Pick Disease Type C and the Birth of Another Involved Sibling

Background: Niemann-Pick disease type C (NPC) is an autosomal recessive neurovisceral lysosomal storage disorder resulting from mutations in either the NPC1 or the NPC2 gene. It shows a broad spectrum of clinical phenotypes and a variable age at diagnosis. As most patients have normal routine examinations (MRI, cerebrospinal fluid, electrophysiology, and so on), its diagnosis is often a challenge, and the start of treatment delays for several years. Case Report: We reported a 9-year-old boy who presented with Stuttered speech, hepatosplenomegaly, and up and downward gaze palsy whose Niemann Pick disease was not diagnosed during infancy due to unawareness. Dried blood spot assay and genetic study confirmed the diagnosis of Niemann Pick disease type C. Conclusion: Due to the high rate of consanguineous marriages and NPC presentation with atypical phenotypes, more educational programs for pediatricians, hematologists, neurologists, endocrinologists, and clinicians help the appropriate and timely diagnosis and prevent another involved sibling.