Copyright 2004, Medicine School of Shandong University 1 Platelet Count Test Institute of Diagnostics Zhong Ning
Copyright 2004, Medicine School of Shandong University 2 Platelet Count
Copyright 2004, Medicine School of Shandong University 3 Platelets are manufactured in bone marrow by megakarocyte. Platelets are only fragments of ctyoplasma. They are removed by spleen when they are old or damage. Reference value 150,000~350,000/ ㎜ 3
Copyright 2004, Medicine School of Shandong University 4 Definition This is a test to measure the number of platelets in blood Platelets are necessary for normal blood clotting (hemostasis).
Copyright 2004, Medicine School of Shandong University 5 Performance 1.Blood is drawn from a vein, usually on inside of the elbow or the back of the hand, or fourth finger. 2.A needle is inserted into the vein, and the blood(20ul) is collected in a tube with platelet dilution(0.38ml). 3.A drop of Platelet suspension added into the Neubauer chamber. 4.Count.
Copyright 2004, Medicine School of Shandong University 6 Neubauer Chamber Improved
Copyright 2004, Medicine School of Shandong University 7
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9 Clinical Significance of Platelet Count Increase Platelet Count (Trombocytosis) Malignant tumor Polycythemia vera Splenecytomy
Copyright 2004, Medicine School of Shandong University 10 Low Platelet Count (Thrombocytopenia) ITP ( idiopathic thrombocytopenic purpura) Acute mass loss of blood AIDS Hemolytic Disorders Hypersplenism ( overactive spleen ) Administration of Heparin
Copyright 2004, Medicine School of Shandong University 11 Occult Blood Test Occult Blood (OB) means Hidden blood that can’t easily been found the presence of blood. Sometimes it is called Guaiac Test Gastroccult is specifically designed to test for occult blood. This test always is used to test the feces (stool).
Copyright 2004, Medicine School of Shandong University 12 Reference Value Healthy person is negative
Copyright 2004, Medicine School of Shandong University 13 Clinical Significance of OB Positive: UGB : upper gastrointestinal bleeding Such as: Gastric ulcer Hepatic cirrhosis gastric mucosa bleeding
Copyright 2004, Medicine School of Shandong University 14 False-Positive Red meat High-fiber diet
Copyright 2004, Medicine School of Shandong University 15 Microscopic examination Cellular elements: erythrocytes leucocytes epithelial cells Casts: Crystals: Brightfield microscopy can be performed unstained urine preparation
Copyright 2004, Medicine School of Shandong University 16 Erythrocytes In normal urine, less than 3RBCs/hpf More than 3RBCs/hpf is abnormal Causes: 1. renal diseases: glomerulonephritis, calculus, tumor 2.urinary tract diseases: acute and chronic infection, calculus, tumor, hemorrhage cystitis 3. toxic reactions due to drugs: anticoagulant therapy
Copyright 2004, Medicine School of Shandong University 17 RBCs in urine Normally, RBCs appear as pale biconcave disks. In hypertonic urine, RBCs become crenated. In dilute urine, RBCs lyse and left only empty cell membranes refer to as “ghost cells”.
Copyright 2004, Medicine School of Shandong University 18 Leukocytes The predominant type of leukocyte is the polymorphonuclear leukocyte (neutrophils) In normal urine, less than 5 leukocytes/hpf Pyuria---more than 5 leukocytes/hpf Causes: urinary tract infection such as pyelonephritis, cystitis, urethritis
Copyright 2004, Medicine School of Shandong University 19 Leukocytes in urine In fresh specimen, leukocytes appear as granular spheres with multilobated nuclei Leukocytes degenerate, nuclear detail may be lost
Copyright 2004, Medicine School of Shandong University 20 Epithelial cells Renal tubular epithelial cells Transitional (urothelial) epithelial cells Squamous epithelial cells
Copyright 2004, Medicine School of Shandong University 21 Renal tubular epithelial cells In normal urine, small numbers of these cells may be seen Increased number indicates tubular damage, such as acute tubular necrosis or certain drug toxicity Larger than leukocytes with a large round nucleus
Copyright 2004, Medicine School of Shandong University 22 Transitional (urothelial) epithelial cells Line the urinary tract from the pelvis to the bladder In normal urine, a few these cells may be seen Increased numbers of cells suggest urinary tract disorders such as infection, calculus Cells larger but nucleus smaller than renal tubular epithelial cells
Copyright 2004, Medicine School of Shandong University 23 Squamous epithelial cells From urethra most frequent epithelial cells seen in normal urine Large clumps suggest urethritis Large and flat with abundant cytoplasm and small round nuclei
Copyright 2004, Medicine School of Shandong University 24 Casts Formed only in the distal convoluted tubule (DCT) or the collecting duct Tamm-Horsfall protein (T-H glycoprotein) forms the matrix of all casts
Copyright 2004, Medicine School of Shandong University 25 Casts The factors which favor protein cast formation are low flow rate, high salt concentration, and low pH (favor protein denaturation and precipitation)
Copyright 2004, Medicine School of Shandong University 26 Casts The protein forms a meshwork that trap any elements present in the tubular filtrate including cells, cell fragments, or granular material
Copyright 2004, Medicine School of Shandong University 27 Casts Very few casts are seen in the urinary sediment Increased numbers or different forms of casts indicate that kidney disease is widespread Casts may be classified according to their matrix, inclusion and cell present
Copyright 2004, Medicine School of Shandong University 28 Hyaline casts Translucent In normal urine, 0~2 hyaline casts/lpf Increased numbers --- renal disease or transiently with exercise, fever, congestive heart failure
Copyright 2004, Medicine School of Shandong University 29 Cellular casts Erythrocyte (RBC) casts Leukocyte (WBC) casts Renal tubular epithelial cell casts
Copyright 2004, Medicine School of Shandong University 30 RBC casts Red blood cells stick together in the cast RBCs casts are indicative of glomerulonephritis or severe tubular damage (severe pyelonephritis)
Copyright 2004, Medicine School of Shandong University 31 WBC cast White blood cells stick together WBC casts’ presence indicates inflammation of the kidney. 1. The most common disease--pyelonephritis 2.Also present with glomerulonephritis
Copyright 2004, Medicine School of Shandong University 32 Renal tubular epithelial cell casts The most reliable distinguishing characterize is their singular round nuclei These casts’ presence suggests tubular injury, such as acute tubular necrosis, exposure to some drugs
Copyright 2004, Medicine School of Shandong University 33 Granular casts Granules may originate from plasma protein aggregates or from cellular remnants of WBCs, RBCs, and damaged renal tubular cells Granular casts’ presence---chronic renal disease
Copyright 2004, Medicine School of Shandong University 34 Waxy casts Homogeneously smooth with sharp margins, blunted ends and cracks along the margins Reflect the final phrase of dissolution of the granular casts waxy casts most frequently in patients with chronic renal failure
Copyright 2004, Medicine School of Shandong University 35 Crystals Form by the precipitation of urinary salts. In vivo, increased solute concentration is typically responsible for crystal formation. Most crystals in the urine are of limited clinical significance. Proper identification of few abnormal crystals is associated with various pathologic conditions.
Copyright 2004, Medicine School of Shandong University 36 Crystals in normal urine Calcium Oxalate Dihydrate crystals Calcium Oxalate Monohydrate crystals
Copyright 2004, Medicine School of Shandong University 37 Crystals in normal urine Triple phosphate crystals
Copyright 2004, Medicine School of Shandong University 38 Crystals in normal urine Uric acid crystals
Copyright 2004, Medicine School of Shandong University 39 Crystals in abnormal urine Sulfadiazine crystals are a common finding with administration of Trimethoprim- sulfadiazine.