Immature Granulocytes (IG)
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The Value-Driven Laboratory The new business model for expanded hematology parameters – Immature Granulocytes (IG) Sysmex America White Paper 577 Aptakisic Road • Lincolnshire, IL 60069 USA www.sysmex.com The Value-Driven Laboratory The new business model for expanded hematology parameters – Immature Granulocytes (IG) These are transformative times in the healthcare industry and especially for the clinical laboratory. Significant reimbursement cuts and payment reform linked to quality measures are driving a new approach to laboratory testing. Laboratorians faced with a changing business model and growing staff shortages are increasingly being asked to justify the value the laboratory provides. Given 70 percent of the data included in a patient’s medical record is generated by the lab, it is reasonable to look to the laboratory to take a leadership role in identifying and implementing new testing systems and clinically valuable parameters to improve patient care while managing cost. This has led to what we call the value-driven laboratory – a laboratory that meets market demands by providing more and new types of diagnostic information to support the delivery of quality, cost-effective patient care. New IG Parameter Adds Value 1. Be easily implemented by the clinical to enumerate the immature cells. to the Routine CBC lab and performed at no additional The sensitivity of flagging can vary by operating cost. hematology analyzer model or by the Sysmex’s advanced clinical parameters settings on the analyzer. The traditional were developed by considering how 2. Reduce CBC review rates and confirmatory 100-cell manual differential expanding the routine CBC might accelerate turnaround times even with growing staff shortages. affect patient care and the healthcare is neither an accurate nor a precise measure of the left shift. Factors that system’s business as a whole. Three 3. Be used by clinicians in conjunction parameters are currently available: with other current indicators for the make the manual 100-cell differential a Immature Granulocytes (IG), Reticulocyte diagnosis of infection/inflammation. poor measure include: Hemoglobin (RET-He) and Immature 4. Be incorporated, along with other 1. Large distribution errors for rare Platelet Fraction (IPF). These parameters current indicators, by coding cell counting, such as immature are automated, reportable immature departments into Clinical Information granulocytes, can result in CVs of cell indices with established clinical System (CIS) algorithms that support >40 percent. See Table 1. applications. patient diagnosis code assignment. 2. Viewing cells on a 2-dimensional slide This article focuses on the automated 5. Become a routine, integral part makes it difficult to differentiate one of quality and cost initiatives in Sysmex Immature Granulocyte (IG) form from another. parameter. A “left shift” is characterized healthcare systems. by the appearance of immature 3. Band cells are especially difficult to neutrophils in the blood, with or without The Growing Clinical and classify and differentiate. neutrophilia. The appearance of immature Operational Value of the granulocytes in the peripheral blood of Immature Granulocyte non-pregnant individuals can indicate Parameter a response to infection, inflammation, Manual Cell Counting is Out or other stimulus to the bone marrow. The immature granulocyte count, When the presence of immature performed on peripheral blood samples, granulocytes in peripheral blood is provides clinically relevant information identified by a flag on an automated to the clinician on immature WBC cell hematology analyzer, the laboratory mobilization that can: usually performs a manual differential 2 Table 1: Precision improves as more cells are counted. In his foundational investigation of the manual differential, Dr. Rumke1 demonstrated here that if a cell’s true concentration is 5 percent, which would be an abnormal elevation in IG’s, the reported results from the 100-cell differential would range from 1.6-11.3 percent at a 95 percent Confidence Interval. Bands are out Subsequently, in the Surviving Sepsis Campaign: International Guidelines for the In the discussion section of a seminal Management of Severe Sepsis and Septic paper in 20022, Dr. P. Joanne Cornbleet Shock: 20123, bands have been removed as brought attention to the fact that there an inflammatory variable for both adult is little clinical utility of a band count. and pediatric patients. In adults, bands “Enumeration of band neutrophils as an have been replaced by the presence of indicator of acute infection is engrained >10 percent immature (WBC) forms even into the clinical practice. Clinicians still with a normal WBC count. In pediatric use elevated band counts, or ‘bandemia’, patients, bands have been replaced by as evidence of serious bacterial infection age-specific WBC cutoffs. and may even use sequential band Figure 1: This photomicrograph shows counts as an indicator of response or band forms that may be difficult to Following are the new diagnostic criteria non response to therapy. Surprisingly, classify consistently using manual for sepsis:3 the clinical folklore of the band persists counting methods. despite little mention of its diagnostic utility in current text books. Text books Surviving Sepsis Campaign: International Guidelines for Management of Severe in Internal Medicine, Hematology and Sepsis and Septic Shock: 2012 Table 1. Diagnostic Criteria for Sepsis. Infection, Laboratory Medicine do not recommend documented or suspected, and some of the following (inflammatory variables band counts for the diagnosis of infection are a section of this list). Bands have been removed. other than to mention that neutrophilia Infection, documented or suspected, and some of the following: and left shift typically accompany infection or inflammation, and similarly Inflammatory variables most pediatric textbooks do not advocate Leukocytosis (WBC count >12,000/μL) band counts for the diagnosis of infection in children over three months old.” Leukopenia (WBC count <4,000/μL) Normal WBC count with >10% immature forms Table 2: Diagnostic Criteria for Sepsis6 3 Immature Granulocytes (IG) and Absolute Neutrophil Count (ANC) are in The Absolute Neutrophil Count reported from automated hematology analyzers includes both mature neutrophils and bands. While these two parameters are important variables in the physician’s diagnosis of inflammation or infection, they may not be adequate. Immature granulocytes are the precursors to the neutrophils and are more immature than the forms that contribute to the ANC. The Sysmex IG is fully automated, rapid, accurate and precise. A study by Dr. B. Fernandes4 demonstrates that the automated IG count on the Sysmex XE-2100™ is very precise and accurate. Table 2 shows that even at low concentrations of WBC and IG (sample 1), the CVs are better than those obtained by manual counting. Together, automated IG and ANC offer a faster, better indicator of left shift than manual band counts. Table 3: Even at low concentrations of WBC and IG (sample 1), the CVs are better than those obtained by manual counting (see the Rumke table in Table 1). Fernandes and Hamaguchi, also found that the automated IG count is more accurate and precise than a 400-cell manual differential and compares well with the flow cytometry reference method. If one looks at the expansion of the WBC diff to include IG as an automated, routinely measured parameter, laboratories of any size and test volume can benefit from a 6-part diff (when IG count is added to the Neuts+Lymphs+Monos+Eo+Baso). Laboratory productivity can improve through reduced review rates and faster turnaround times. 4 The Value-Driven Laboratory: Supporting the Continuum of Care The physician’s need to identify responses to infection or inflammation occurs throughout the care continuum potentially impacting both quality and cost of care. In an article in Beckers Hospital Review, Nov. 29, 2011, Ann Pumpian, CFO of Sharp Healthcare in San Diego says, “hospitals will need to look at the entire continuum of care, regardless if they join an ACO, if they plan to stay profitable”.5 In-Patient Management Admission Care Path Discharge in Post-Acute Follow Up Setting Figure 2: Continuum of Patient Care. Laboratory results can impact physician decisions at every point in the continuum of care. In this section, we will look at examples Post-Surgical Readmissions Clinicians Perceptions of the of Hospital-Acquired Infections and post Alicia Caramenico of FierceHealthcare4, Laboratory: Getting a “B” isn’t surgical readmissions as well as clinicians in discussing the pressures hospitals good enough perceptions of the clinical laboratory. We face to improve patient safety and care In a recent article that appeared in will also suggest how labs can begin to quality, cited an example that almost 1 CAP Today7, Kirsten Alcorn, MD, Senior benchmark the return of adopting the in 10 general surgery patients returns Pathologist and Medical Director of automated IG. to the hospital with post-operative the Transfusion Services at MedStar Hospital-Acquired Infections complications. (FierceHealthcare, Washington Hospital Center, Washington, 6 Hospital Acquired Infections (HAIs) are October 18, 2012 ). Under current federal DC and Medical Director of Blood Donor costly, life threatening, and are attached healthcare payment reform initiatives, Services for MedStar Health, reported to hospital quality measures. Patient hospitals with high levels of preventable on a