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 examine the cherry red spot in the macula of the eye? I. Symptoms and signs This disease is common in infancy and childhood, usually normal at birth, and symptoms appear within 6 months after birth. Early manifestations are loss of appetite, vomiting, diarrhea, low nutrition and obvious emaciation, the patient’s face is pale, the skin is waxy yellow, or brownish yellow pigmentation, physical and motor development are delayed, intelligence gradually decreases and becomes idiot-like. In some cases, deafness, blindness, paralysis and other symptoms may occur, as well as limb tonicity, tremors and even convulsions. On physical examination, there is parallel enlargement of the liver and spleen, up to 10 cm below the rib cage, with a hard texture. The lymph nodes may also be mildly enlarged. In about 1/3 of cases, cherry red spots are seen in the macula on fundus examination, identical to those seen in black haze familial idiots; anemia is generally not severe, with high white blood cells and relatively increased lymphocytes in the early stages. Large vacuoles are seen in the cytoplasm of lymphocytes and monocytes; late platelets can be reduced, serum neutral fat is increased, neurophospholipids are normal, cholesterol is normal or slightly high, liver function is generally normal or slightly poor; clinically there are three main types, and there are also reports in the literature to divide it into five types. 1, acute infantile type (type A): this type accounts for about Nie-mann-Pick cases more than 85%, most cells in the body lack of sphingomyelinase, clinical symptoms of liver, spleen, lymph node enlargement and neurological damage, half of the patients appear cherry red spots around the macula of the fundus. This type of disease develops rapidly, and most die within 3 years from severe consumption and infection. 2. Chronic visceral type (type B): It occurs in infancy and childhood, showing growth retardation and slow progression, and most patients die in their teens or when they first enter adulthood. The liver, spleen and lymph nodes are enlarged, sometimes with hypersplenism, and there are usually no neurological manifestations. Type C: All manifestations of this type can be present, and some patients do not have sphingomyelinase deficiency. Patients may present in infancy with slowly progressive visceral lesions and late onset of neurological lesions, or in adulthood with visceral lesions only. II. Diagnostic tests The disease should be suspected in those with large liver and spleen in infancy, and the liver is 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 the lung X-ray, and the important diagnostic basis is the typical foam-like Niemann-Pick cells found in the bone marrow. Sphingomyelinase activity measurement can confirm the diagnosis if it is reduced. Laboratory tests Blood tests may include 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 have vacuoles.