Essential thrombocythemia in the elderly
Introduction
Introduction to elderly patients with essential thrombocytosis Primary thrombocytosis is a clonal disease in which megakaryocytes are abnormally proliferating, characterized by thrombocytosis, abnormal morphology and function. The main clinical features are significant, persistent increases in platelets of unknown cause, and a tendency to hemorrhage and thrombosis. More than half of them have splenomegaly. basic knowledge The proportion of illness: 0.004% Susceptible people: the elderly Mode of infection: non-infectious Complications: epilepsy
Cause
The cause of essential thrombocytosis in the elderly
(1) Causes of the disease
The cause is unknown.
(two) pathogenesis
The mechanism of thrombocytosis is still unclear. It may be due to abnormalities of hematopoietic stem cells, proliferation of megakaryocyte cell line, increased platelet production and excessive release of platelets from spleen and liver reservoirs into circulating blood. The main cause of bleeding is the extremely high number of platelets. Or combined with vascular degeneration lesions caused by intravascular thrombosis, infarct zone collapse and platelet function and abnormal blood coagulation mechanism, megakaryocyte cell proliferation may also involve extramedullary tissue, such as liver, spleen megakaryocyte-based hyperplasia, in addition I have seen familial essential thrombocytosis.
Prevention
Prevention of essential thrombocytosis in the elderly
For patients with severe bleeding tendency, in addition to controlling the number of platelets, fresh platelet preparations should be infused in time to prevent intracranial hemorrhage.
Complication
Elderly patients with essential thrombocytopenia complications Complications epileptic cerebral hemorrhage
Complications are easy to hemorrhage, mesenteric and spleen embolism epilepsy, cerebral hemorrhage.
Symptom
Symptoms of essential thrombocytosis in the elderly Common symptoms Erythrocytosis, epistaxis, thrombocytopenia, menstrual flow, acute abdomen, splenic embolism, ecchymosis
Most patients have symptoms of hemorrhage and/or thrombosis. Hemorrhage is common, especially in the gastrointestinal tract, gums and nosebleeds. Female patients often have menorrhagia, sputum, and ecchymoses are rare. It is easy to bleed after spontaneous or minor trauma. The corresponding part of thrombosis has necrosis and/or secondary atrophic lesions, and its manifestations are diversified. Arterial thrombosis is more common in limbs, and intermittent limb cyanosis causes intermittent claudication; Peripheral arterial thrombosis of the extremities causes finger (toe) pain or gangrene; mesenteric and spleen embolism manifests as acute abdomen, lung, kidney, brain or adrenal gland, etc. Once thrombosis occurs, the disease changes, or even dies, about 80% of patients have obvious The spleen is swollen, and there is also a spleen that is not swollen. It may be caused by repeated embolization and atrophy. The liver may also be swollen, gout is rare, and some patients are asymptomatic for a long time.
Examine
Examination of elderly patients with essential thrombocytosis
1. The blood platelet count is >1000×109/L, which persists, even up to 1400×109/L, so that the platelets cannot be counted. The piles of platelets are seen in the blood smear, the size is not uniform, the shape is singular, and there are huge. Spherical, cytoplasmic pseudopodia platelets, occasionally megakaryocytes and fragments, red blood cell counts are mostly normal, a few have mild erythrocytosis, when accompanied by spleen atrophy, Howell-Jolly body can be seen in blood smears And target cells, white blood cell counts are mostly increased, mostly in (10 ~ 40) × 109 / L, classification sees neutrophil increase and nuclear "left shift" phenomenon, also can be seen in late granulocytes and myelocytes and hobby Acid and basophils are slightly increased.
2. Bone marrow examination The nucleated cells in the bone marrow smear increased significantly, especially in megakaryocytes, often clustered or flaky, immature megakaryocytes increased and platelets were produced, and huge heterogeneous megakaryocytes were also seen. Significantly increased platelets, aggregated into heaps, and pleomorphic megakaryocyte proliferation (huge and small megakaryocytes) were also seen in bone marrow biopsies, clustered or diffusely distributed.
3. Electron microscopy of platelet ultrastructure has various morphological changes, platelets are spherical or abnormally enlarged, particles and dense particles are reduced, and shaped particles appear, such as rod-shaped particles, open duct system hypertrophy, hyperplasia or rupture, appear Rough endoplasmic reticulum pool, well-developed Golgi complex and myelin sheath.
4. Platelet function test bleeding time prolonged, capillary fragility test is positive, blood clot retraction is poor or retraction, platelet adhesion rate is reduced, common to platelet aggregation, the aggregation of the inducer is weakened, some patients platelet Decreased factor III activity, increased platelet factor IV activity, platelet membrane glycoprotein I decreased significantly, membrane protein IV increased significantly, membrane alpha-adrenergic receptor number decreased, thromboelastogram (TEG) examination, most showed maximum thrombus The amplitude (Ma) increases (60mm or more), and a few are typical "bottleneck" types.
5. Other neutrophil alkaline phosphatase activity increased, serum uric acid and vitamin B12 often increased, serum levels of potassium, phosphorus, zinc, mucopolysaccharide, lactate dehydrogenase, acid phosphatase and -thromboxin Increased, even pseudohypoxemia, abnormal chromosomes, including super-ploid, low diploid and C group of chromosome additions or deletions, it is believed that 21q-phenomenon is an important feature of chromosome aberrations in this disease There is no typical Ph chromosome, and the plasma fibrinogen content is normal, which is helpful for identification with reactive thrombocytosis.
If combined with cerebral hemorrhage, CT scan can find abnormalities.
Diagnosis
Diagnosis and differentiation of elderly patients with essential thrombocytosis
Diagnostic criteria
The diagnosis basis includes: 1 history of hemorrhage and/or thrombosis, splenomegaly; 2 platelet count>1000×109/L (1 million/mm3), accompanied by abnormal morphology and function; 3 increased white blood cell count; 4 myeloid hyperplasia, The proliferation of megakaryocyte cell line is particularly prominent, and a large number of platelets are formed; 5 can exclude reactive or secondary thrombocytosis and polycythemia vera, etc., and the platelet continuous and significant increase is the most important basis.
Differential diagnosis
Reactive and secondary thrombocytopenia are mainly seen after spleen resection, acute infection recovery, localized ischemic colitis, chronic inflammation, hemolytic anemia, tuberculosis, sarcoidosis, rheumatoid arthritis, cirrhosis, sub Acute bacterial endocarditis and malignant tumors, etc., the degree of reactive thrombocytosis is mostly mild, moderate, generally not more than 1000 × 109 / L (1 million / mm3), and often temporary, in addition, serum lactate Dehydrogenase increased, platelet size uneven, splenomegaly, hemorrhage, thrombosis and platelet morphology and dysfunction were not seen, or were not common in reactive or secondary thrombocytosis, so identification is not too difficult.
