aubf-microscopic-examination-of-urine.pdf

lOMoARcPSD|41806088 AUBF Microscopic Examination of Urine Medical Laboratory Science (Liceo de Cagayan University) Scan to open on Studocu Studocu is not sponsored or endorsed by any college or university...

lOMoARcPSD|41806088 AUBF Microscopic Examination of Urine Medical Laboratory Science (Liceo de Cagayan University) Scan to open on Studocu Studocu is not sponsored or endorsed by any college or university Downloaded by Johnloyd Rico ([email protected])  lOMoARcPSD|41806088 MICROSCOPIC EXAMINATION OF URINE purpose is to detect and to identify insoluble materials present in the urine RBCs, WBCs, epithelial cells, casts, bacteria, yeast, parasites, mucus, spermatozoa, crystals, and artifacts ★ Macroscopic Screening ★ Sediment Examination Techniques ➔ SEDIMENT STAINS ➔ SPECIMEN PREPARATION specimens should be examined while fresh or adequately preserved formed elements, primarily RBCs, WBCs, and hyaline cast, disintegrate rapidly, particularly in dilute alkaline urine ➔ MICROSCOPY midstream clean-catch specimen Bright-field microscopy: most common; minimizes external contamination of the used for routine urinalysis sediment Phase-contrast microscopy: enhances ➔ SPECIMEN VOLUME visualization of elements with low standard volume is 10-15 ml refractive indices, such as hyaline casts, if volume of 10-15 ml is not possible (i.e. mixed cellular casts, mucous threads, and pediatric patients), the volume of the Trichomonas specimen used should be noted on the Polarizing microscopy: aids in the report form identification of cholesterol in oval fat ➔ CENTRIFUGATION bodies, fatty casts, and crystals centrifugation for 5 mins at an RCF of 400 Dark-field microscopy: aids in produces an optimum amount of sediment identification of Treponema pallidum with the least chance of damaging the Fluorescence microscopy: allows elements visualization of naturally fluorescent ➔ SEDIMENT PREPARATION microorganisms or those stained by a / EXAMINATION fluorescent dye including labeled antigens volume a er decantation should be 0.5-1 and antibodies ml Interference-contrast: produces a the slide is first examined under LPO to three-dimensional microscopy image and detect casts and to ascertain the general layer-by-layer imaging of a specimen composition of the sediment when elements such as casts that require ★ Urine Sediment Constituents identification are encountered, the setting ➔ RED BLOOD CELLS is changed to high power appear smooth, non-nucleated, biconcave sediments should be examined under disks measuring approximately 7 mm in reduced light when using bright-field diameter microscopy must be identified under HPO ➔ REPORTING RESULTS casts: average number per low-power field (/lpf) RBCs & WBCs: average number per high-power field (/hpf) epithelial cells, crystals, & other elements: semiquantitave terms such as rare, few, moderate, and many, or as 1+, 2+, 3+, and crenated RBCs: cell shrinkage due to loss 4+ per lpf or hpf of water (hypersthenuric) ghost cells: cell swelling and lysis due to absorbance of water (hyposthenuric) Downloaded by Johnloyd Rico ([email protected])  lOMoARcPSD|41806088 are frequently confused with yeast cells, oil ○ increase in urinary WBCs: pyuria droplets, and air bubbles (indicates the presence of an infection ○ yeast: look for buds or inflammation in genitourinary ○ oil droplets: refractility system) ○ air bubbles: refractility and possibly in ○ bacterial infections: pyelonephritis, a different plane cystisis, prostatisis, and urethritis ○ starch: refractile; polarizes ○ nonbacterial disorders: glomerulonephritis, lupus erythematosus, interstitial nephritis, and tumors ➔ EPITHELIAL CELLS represent normal sloughing of old cells, dysmorphic RBCS unless present in large numbers or in ○ RBCs that vary in size, have cellular abnormal forms protrusions, or fragmented squamous epithelial cells ○ associated with glomerular bleeding ○ largest cells found in urine ○ aid in determining site of renal ○ few squamous cells seen in urine is bleeding normal ○ also demonstrated a er strenuous ○ originate from the linings of the vagina exercise and female urethra and the lower CLINICAL SIGNIFICANCE portion of the male urethra ○ normal value: 0-3 to 5 /hpf ○ clue cells: indicative pf vaginal ○ presence is associated with the infection caused by Gardnerella vaginalis genitorurinary tract ○ no. of cells = extent of damage ○ macroscopic hematuria: advanced glomerular damage; urine appears cloudy with a red to brown color ○ microscopic hematuria: early glomerular disorders or presence of renal calculi transitional epithelial cells ➔ WHITE BLOOD CELLS ○ smaller than squamous cells larger than RBCs, measuring an average of ○ appear in several forms, including about 12 mm in diameter spherical, polyhedral, and caudate predominant WBC found is neutrophil ○ identified and enumerated using HPO easier to identify because they contain ○ originate from the lining of the renal granules and multilobed nuclei pelvis, calyces, ureters, and bladder and identified under HPO (/hpf) from the upper portion of the male urethra ○ normally present in small numbers (normal cellular sloughing) ○ increased numbers are present following invasive urologic procedures (catheterization) glitter cells: neutrophils exposed to hypotonic urine (cell swelling); produces a sparkling appearance eosinophils ○ associated with drug-induced interstitial nephritis renal tubular epithelial cells ○ small numbers seen with UTI and renal ○ vary in size and shape depending on the transplant rejection area of the renal tubules from which ○ preferred stain: Hansel stain they originate ○ finding of >1% is significant ○ columnar/convoluted: mononuclear cells - originates from the PCT ○ lymphocytes may resemble RBCs and - largest RTE cells seen in increased numbers in early - o en resemble a cast stages of renal transplant rejection ○ primary concern is the differentiation of mononuclear cells and disintegrating neutrophils from round RTE cells CLINICAL SIGNIFICANCE ○ normal value: