Biomaterial Database

Absolute lymphocyte count as a predictor of CD4 count. 1998

N I Shapiro, and D J Karras, and S H Leech, and K L Heilpern

Division of Emergency Medicine, Temple University School of Medicine, Philadelphia, PA, USA. NSHAPIR01@AOL.COM

OBJECTIVE To determine whether the absolute lymphocyte count (ALC) (white blood count x lymphocyte percentage) can be used to predict a low CD4 count. METHODS We conducted a retrospective data analysis of consecutive CD4 count analyses performed between January 1, 1995, through December 1, 1995, at an urban university teaching hospital. Results of consecutive CD4 counts and simultaneously measured ALCs were analyzed from samples obtained in inpatient, clinic, and emergency department settings. The ability of ALC to predict a CD4 count less than 200 cells/mm3 was analyzed by calculating sensitivities, specificities, predictive values, and likelihood ratios for a range of ALC values. RESULTS Among the 807 samples, 322 results (40%) had a CD4 count less than 200 cells/mm3. The ALC and CD4 count were correlated (r=.69, P<.0001). An ALC less than 1,000 cells/mm3 predicted CD4 counts less than 200 cells/mm3 with a sensitivity of .67 (95% confidence interval .62 to .72), specificity of .96 (.94 to .98), positive predictive value of .91 (.87 to .95), and a negative predictive value of .81 (.78 to .84). An ALC less than 2,000 cells/mm3 predicted CD4 counts less than 200 cells/mm3 with a sensitivity of .97 (.95 to .99), specificity of .41 (.37 to .45), positive predictive value of .52 (.48 to .56), and negative predictive value of .95 (.92 to .98). CONCLUSIONS A reliable relationship exists between ALC and CD4 count. In a similar population, an ALC less than 1,000 cells/mm3 is predictive of a CD4 count less than 200 cells/mm3, and an ALC greater than or equal to 2,000 cells/mm3 is predictive of a CD4 count greater than or equal to 200 cells/mm3. Physicians may find these criteria useful in identifying patients with increased risk of opportunistic infection.

UI	MeSH Term	Description	Entries
D007958	Leukocyte Count	The number of WHITE BLOOD CELLS per unit volume in venous BLOOD. A differential leukocyte count measures the relative numbers of the different types of white cells.	Blood Cell Count, White,Differential Leukocyte Count,Leukocyte Count, Differential,Leukocyte Number,White Blood Cell Count,Count, Differential Leukocyte,Count, Leukocyte,Counts, Differential Leukocyte,Counts, Leukocyte,Differential Leukocyte Counts,Leukocyte Counts,Leukocyte Counts, Differential,Leukocyte Numbers,Number, Leukocyte,Numbers, Leukocyte
D009894	Opportunistic Infections	An infection caused by an organism which becomes pathogenic under certain conditions, e.g., during immunosuppression.	Infection, Opportunistic,Infections, Opportunistic,Opportunistic Infection
D011237	Predictive Value of Tests	In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.	Negative Predictive Value,Positive Predictive Value,Predictive Value Of Test,Predictive Values Of Tests,Negative Predictive Values,Positive Predictive Values,Predictive Value, Negative,Predictive Value, Positive
D005544	Forecasting	The prediction or projection of the nature of future problems or existing conditions based upon the extrapolation or interpretation of existing scientific data or by the application of scientific methodology.	Futurology,Projections and Predictions,Future,Predictions and Projections
D006785	Hospitals, University	Hospitals maintained by a university for the teaching of medical students, postgraduate training programs, and clinical research.	University Hospitals
D006786	Hospitals, Urban	Hospitals located in metropolitan areas.	City Hospitals,Hospitals, City,Hospitals, City, Non-Public-Owned,Hospitals, Metropolitan,Urban Hospitals,City Hospitals, Non-Public-Owned,Metropolitan Hospitals,Non-Public-Owned City Hospitals,City Hospital,City Hospital, Non-Public-Owned,City Hospitals, Non Public Owned,Hospital, City,Hospital, Metropolitan,Hospital, Non-Public-Owned City,Hospital, Urban,Hospitals, Non-Public-Owned City,Metropolitan Hospital,Non Public Owned City Hospitals,Non-Public-Owned City Hospital,Urban Hospital
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D012189	Retrospective Studies	Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.	Retrospective Study,Studies, Retrospective,Study, Retrospective
D012307	Risk Factors	An aspect of personal behavior or lifestyle, environmental exposure, inborn or inherited characteristic, which, based on epidemiological evidence, is known to be associated with a health-related condition considered important to prevent.	Health Correlates,Risk Factor Scores,Risk Scores,Social Risk Factors,Population at Risk,Populations at Risk,Correlates, Health,Factor, Risk,Factor, Social Risk,Factors, Social Risk,Risk Factor,Risk Factor Score,Risk Factor, Social,Risk Factors, Social,Risk Score,Score, Risk,Score, Risk Factor,Social Risk Factor
D012372	ROC Curve	A graphic means for assessing the ability of a screening test to discriminate between healthy and diseased persons; may also be used in other studies, e.g., distinguishing stimuli responses as to a faint stimuli or nonstimuli.	ROC Analysis,Receiver Operating Characteristic,Analysis, ROC,Analyses, ROC,Characteristic, Receiver Operating,Characteristics, Receiver Operating,Curve, ROC,Curves, ROC,ROC Analyses,ROC Curves,Receiver Operating Characteristics