We recently treated a 12-day-old male infant who was presented with respiratory distress, hepatosplenomegaly, and lipemia retinalis. The laboratory notified us that his blood samples were unusually viscous and pinkish-white and turned opaque milky white in about 10 minutes. The acute phase reactants were consistent with inflammation but the cultures remained sterile. Sera showed chylomicronemia with high triglyceride and cholesterol levels. We changed feedings to a special formula containing medium-chain fatty acids. Genetic analysis showed a novel homozygous mutation in the lipoprotein lipase (LPL) gene. In addition, he had a heterozygous missense variation in the sterol regulatory element-binding transcription factor 2 (SREBF2) gene. His father was also found to have hypertriglyceridemia and is being evaluated. This case reminds us yet again that not every infant with respiratory distress has an infection as the underlying cause. Timely diagnosis and intervention can improve outcomes.
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