Atypical pyloric stenosis in an infant with familial hyperlipidemia.

A 1-month-old infant presented with a typical pattern of pyloric stenosis but US revealed an intense hyperechogenicity of the thickened pyloric muscle. Cholecystitis and pancreatitis were also present in this child. Familial hyperchylomicronemia was detected. Surgery confirmed the fatty infiltration of the pyloric muscular layer, which was necrotic and inflammatory. Medical management with restriction of fat in the diet led to a complete recovery. This is an exceptional case of pyloric stenosis where the particular echographic appearance of the pyloric muscle led to successful to medical treatment.