Case report of a novel variant in SMPD1 of Niemann-Pick disease type A with a liver histology from Thailand

Abstract

We report a 7-month-old Thai girl diagnosed with a Niemann-Pick Disease (NPD) Type A. Hepatosplenomegaly was initially noticed at the age of 2 months. She developed progressive neurodevelopmental delay at 5 months. Other typical manifestations include coarse facies, cherry red spot of macula, hypotonia, and failure to thrive. A liver biopsy demonstrated an accumulation of enlarged histiocytes with foamy appearance in hepatic sinusoids. An acid sphingomyelinase activity from dried blood spot showed low activity. A novel c.1241T>C variant in SMPD1 was identified. The patient died at 4 years of age due to neurological decline and respiratory failure. Even in type A, onset of systemic symptoms occurs before neurodevelopmental delay. NPD type A is exceptionally rare in Thailand. Infantile neurovisceral ASMD prognosis is poor, often fatal by age 3. No specific NPD type A treatment exists; supportive care is offered. Therefore, the case reveals a novel SMPD1 variant in typical NPD type A symptoms. Early progressive neurodevelopmental delay challenges treatment study.

Keywords

• Niemann-Pick disease
• NPD type A
• Acid sphingomyelinase deficiency
• Hepatosplenomegaly
• Cherry-red spots