Differential counts

The basic aperture impedance method can produce three-part white cell differential counts. Impedance counters can distinguish three white cell types by size the LYMPHS, mid-range cells including MONOS and BASOS, and granulocytes including NEUTS and EOS. 

SUCCINIMIDES. The succinimides are particularly toxic. The nurse must be alert for signs of blood dyscrasias, such as the presence of fever, sore throat, and general malaise The nurse reports any of these symptoms immediately because fatal blood dyscrasias have occurred. Routine blood tests may be performed, such as complete blood counts and differential counts. 

Glucose Lactic dehydrogenase (LDH) Phosphorus Potassium Serum glutamic-oxaloacetic transaminase (SGOT) Serum glutamic-pyruvic transaminase (SGPT) Sodium Total bilirubin Total cholesterol Total protein Triglycerides White cell differential count ... 

Immunopathology Routine hematology—complete and differential count routine toxicology information—weights of body, immune organs (spleen and thymus), liver, and kidney histopathology of immune organs. 

Consideration of the white blood cell (WBC) and differential counts leads to another problem. The total WBC is, typically, a normal population amenable to parametric analysis, but differential counts are normally determined by counting, manually, one or more sets of one hundred cells each. The resulting relative percentages of neutrophils are then reported as either percentages or are multiplied by the total WBC count with the resulting count being reported as the absolute differential WBC. Such data, particularly in the case of eosinophils (where the distribution does not approach normality), should usually be analyzed by nonpara-metric methods. It is widely believed that relative (%) differential data should not be reported because they are likely to be misleading. 

Monitoring Perform baseline and periodic leukocyte and differential counts and liver function studies. Fever or sore throat may signal serious neutrophil depression discontinue therapy if there is evidence of pathological neutropenia. 

Monitoring Discontinue maprotiline if there is evidence of pathological neutrophil depression. Perform leukocyte and differential counts in patients who develop fever and sore throat during therapy. 

Lab test abnormalities Discontinue the drug in any patient whose white blood cell count or absolute neutrophil count falls below normal levels. White blood cell and differential counts are recommended for patients who develop fever and sore throat (or other signs of infection) during therapy. 

Patients who are being treated with clozapine must have a baseline white blood cell (WBC) and differential count before initiation of treatment and regular WBC counts during treatment and for 4 weeks after the discontinuation of clozapine. 

Repeat WBC and differential counts. Symptoms of infection include the following lethargy, weakness, fever, sore throat. 

Interrupt therapy, monitor for flu-like symptoms or other symptoms of infection. May resume therapy if no signs of infection develop, WBC count > 3,000, and granulocyte count > 1,500. However, continue twice/wk WBC and differential counts until WBC returns to 3,500. 

The various organs of the immune system such as spleen, lymph nodes, thymus and bone marrow containing the cells involved in the various immune responses offer the possibility to harvest these cells and perform in vitro assays for evaluation of effects on the immune system. When part of an in vivo animal study this may indicate a direct toxic effect of pharmaceuticals, that is, immunosuppression (Table 18.2). So, it is feasible to obtain cell suspensions for further evaluation such as determination of cellular subsets of T and B leukocytes by fluorescent activated cell sorter analysis (FACS analysis), and determination of natural killer (NK) cell activity of the spleen cell population. An advantage of this approach is that it may lead to identification of a biomarker to be used in clinical studies. In addition, in vitro stimulation of spleen cells with mitogens activating specific subsets may indicate potential effects on the functionality of splenic cell populations. Concanavalin A (Con A) and phytohemagglutinin (PHA) activate Tcells, while lipopolysaccharide (LPS) activates primarily B cell populations. Blood is collected for total white blood cell (WBC) determination and blood cell differential count. In addition, serum can be obtained for determination of serum immunoglobulins. 

Agranulocytosis is a potentially catastrophic idiosyncratic reaction that usually appears within the first 3 months of therapy. Although the incidence is extremely low (except for clozapine), mortality is high. Thus, any fever, sore throat, or cellulitis is an indication for discontinuing the antipsychotic and immediately conducting white blood cell and differential counts. 

Routine blood differential counts and urinalyses analyses obtained 7 d after CA exposure are available on 12 subjects. One subject had minimal leukocytosis (WBC, 12,800) that was not seen in his pre-exposure laboratory analyses. 

If WBC count is 2,000-3,000/mm or ANC is 1,000-1,500/mm, interrupt therapy and monitor for signs of infection. Perform WBC and differential counts daily. If there are no symptoms of infection, if WBC count returns to greater than 3,000/mm, and if ANC is greater than 1,500/mm, resume clozapine therapy with twice-weekly WBC and differential counts until total WBC count returns to more than 3,500/mm and ANC is greater than 2,000/mm. ... 

Reactions to antithyroid drugs have been described above. A minor rash can often be controlled by antihistamine therapy. Because the more severe reaction of agranulocytosis is often heralded by sore throat or high fever, patients receiving antithyroid drugs must be instructed to discontinue the drug and seek immediate medical attention if these symptoms develop. White cell and differential counts and a throat culture are indicated in such cases, followed by appropriate antibiotic therapy. 

The sum 2fk,e> in eq. (10-10) corresponds to counting all the photons admitted by the photon-counting apparatus. Re (a) represents the real part of the (complex number) a. As expected, eq. (10-10) contains a direct decay term and interference terms. To study further the consequences of eq. (10-10) consider the expression for the differential counting rate ... 

Turning now to the quantum beat experiment, we find that the differential counting rate is given by... 

The number of leukocytes after treatment with a sub-lethal dose of 5FU decreased and reached its lowest level on day 7, followed by gradual recovery (data not shown). In the CVS group, the overall kinetics were almost the same, but the levels of leukopenia on day 4 were weaker and a rapid recovery was observed. CVS administration did not influence the total leukocyte counts or the differential counts in untreated normal mice (data not shown). 

Hematology. Assessment should be made prior to chemical administration (pretest) and at least prior to termination. Hemoglobin, hematocrit, RBC, WBC, differential counts, platelets, reticulocytes, and clotting parameters should be assessed. 

Immunological (e.g., leukocrit values and blood differential counts)... 

Differential cell counts of the BAL and peritoneal fluids are performed on cytospin-prepared slides. Differential counts of leukocytes in peripheral blood are performed on blood smears. The slides are stained with Diff-Quik (American Scientific Products, McGaw Park, IL) and at least 200 cells are counted per sample to determine the percent of neutrophils, macrophages, lymphocytes, and other cells. 

A 36-year-old HIV-positive man taking zidovudine, lamivudine, and indinavir was noticed to have a mild asymptomatic anemia (hemoglobin 10.2 g/1, white cell count 10.4 x 109/1 with a normal differential count, and platelets 237 x 109/1). The blood film suggested hemolysis. He had taken ecstasy 2 weeks earlier for the first time. The anemia was reportedly secondary to oxidative stress, probably due to drug toxicity. Three weeks later his hemoglobin returned to normal. 

Leukocyte and differential counts (including platelet counts) must be normal before starting treatment with drugs that have the potential to cause blood dyscrasias or bone marrow suppression. 

In 44 patients with multiple recalcitrant warts randomized to either oral cimetidine 30 mg/kg/day in three doses for 12 weeks, or 30 mg/kg/day for 12 weeks plus levamisole 2.5 mg/kg for 2 days per week, cimetidine plus levamisole produced significant improvement (22). Adverse effects of levamisole were infrequent, except for a metallic taste in one patient and nausea in two. In one patient the nausea was severe enough to necessitate withdrawal. There were no significant changes in leukocyte count or differential counts. 

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