How to interpret Histograms in CBC | Analysis of CBC report with histogram interpretation

How to interpret Histograms in CBC | Analysis of CBC report with histogram interpretation Blood cell histograms are produced by the modern automated haematology analysers which are routinely used to count blood cells. A good interpretation of this histogram provides a wealth of information on many haematological conditions than mere cell counts, helping to narrow down the differential diagnosis at a very early stage even before higher level investigations are ordered. Histogram interpretation needs careful analysis of RBC, WBC and platelet distribution curves. These curves also known as Complete Blood Count (CBC) histogram are derived by plotting the size of each cell on X-axis and their relative number on Y-axis. White Blood Cells. The peaks in the WBC histogram, separated by discriminator bars, correspond withLYM, MON, and GRA. Debris (lysed RBCs) from the WBC counting step may be seen to the left of thefirst discriminator bar. • Lymphocyte. The LYM peak (left) is seen to the right of the first discriminator bar. In canines, the LYM peakstarts on the low-to-mid portion along the Y-axis, as shown, indicating lower populations of this cell type. Infelines, the LYM peak starts on the mid-to-high portion of the y-axis due to higher relative number of LYM • Monocyte. The MON peak (center) is seen to the right of the second discriminator bar, and is typicallyshorter due to a smaller population relative to other WBCs • Granulocyte. The GRA peak (right) is seen to the right of the third discriminator bar, and is predominantlycomprised of neutrophils. It is the tallest and widest peak, indicating it is the most numerous WBC Eosinophil. The EOS histogram varies and may be symmetrical or asymmetrical, jagged or smooth. Debris (lysed cells) from the EOS counting step may be seen to the left of the discriminator bar. It is not uncommon for the EOS discriminator bar to appear on the edge of the EOS peak. • The eosinophils are counted separately from the other WBC types, and are thus shown in a separate histogram • Interpreting EOS by focusing on the numerical HM5 data is recommended Platelet. The PLT histogram begins with a sharp increase to a peak and tapers downward as cell size increases. This indicates that the majority of platelets are smaller in size, with fewer large sized platelets. The RBC peak can be seen starting to the right of the discriminator bar. • In felines, the histogram tapers downward less sharply, indicating more cells of a larger size, commonly associated with mild platelet clumping • The reported PLT number is the minimum number of free platelets counted by the analyzer • PLT histogram should be evaluated whenever the PLT count is low and/or lymphocytes are elevated. A blood smear to confirm a low platelet count is also recommended. Red Blood Cells. The RBC histogram in normal dogs and cats should present as an almost symmetrical, bell-shaped curve. The PLT peak can be seen to the left of the discriminator bar. #CBCHistograms #HistogramInterpretation #DataAnalysis #CBCResults #MedicalInterpretation • The width of the curve relates to the red cell distribution width (RDW) • An increased RDW would show on the RBC histogram as a wider peak, and mean that some of the RBCs