Niemann-Pickrsquo;s disease (NPD) is an inherited metabolic disease caused by the deposition of sphingomyelin and cholesterol in various organs of the body. The disease was first reported by Niemann in 1914 as the first case, and in 1922 Pick described in detail what was seen on pathological examination, hence the name. Two cases were first reported in China in 1963, and individual cases have been reported since then. How to diagnose cherry red discoloration in the macula of the eye? Symptoms and signs 1, type A: feeding difficulties, malnutrition, hepatomegaly, splenomegaly, often preceded by hepatomegaly, lymph node enlargement, mental neurodevelopmental delay, but because it proceeds slowly, it is often undetected in the months after the disease, not only does not meet the developmental standards of the age, but also appears regression, muscle strength is also reduced. In severe cases, hearing and vision are affected or even lost. 30% to 50% of patients have cherry-red spots in the macula of the eye. The child gradually loses weight and often dies before the age of 3 to 4 years due to secondary infection. 2.Type B: This type progresses very slowly, except for liver and spleen enlargement, there is no or only slight neurological manifestations, and can live with the disease for a long time. 3.Type C and D: The child behaves normally for several years after birth, and then gradually develops neurological symptoms, such as: reduced vocabulary, ataxia, convulsions, supranuclear ophthalmoplegia. The liver is large and the spleen is not as large as the liver. Type C is similar to type D, but type C is common in NovaScotia, Canada. Some unexplained neonatal hepatitis has been found in patients with type C. Diagnostic tests The disease should be suspected in infants with large liver and spleen, which are larger than the spleen, and progressive neurological manifestations. The diagnosis of the disease is supported by cherry-red spots found in the macula and corn-like changes in lung radiographs, and the important diagnostic basis is the typical foam-like Niemann-Pick cells found in the bone marrow. Sphingomyelinase activity assay with reduced sphingomyelinase activity can confirm the diagnosis. Laboratory tests Blood tests may show moderate anemia and thrombocytopenia, the extent of which depends on the extent of bone marrow involvement. Leukocytes are generally normal, may be reduced or even slightly increased, and lymphocytes and monocytes may be vacuolated.