Use of the relationship between absolute lymphocyte count and CD4 count to improve earlier consideration of pneumocystis pneumonia in HIV-positive emergency department patients with pneumonia

Anthony M. Napoli, Brandon Maughan, Ryan Murray, Kevin Maloy, David Milzman

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Background: The ability to accurately assess the level of immunosuppression in HIV+ patients in the emergency department (ED) is often limited and can affect management of these patients. Objective: To evaluate the relationship between the absolute lymphocyte count (ALC) and CD4 count in HIV patients admitted through the ED with pneumonia and how utilization of this relationship may affect early consideration and evaluation of Pneumocystis jiroveci pneumonia (PCP). Methods: Retrospective multicenter 5-year study of HIV+ patients with an ICD-9 diagnosis of pneumonia. Included patients had an ALC measured on ED presentation and a CD4 count measured in < 24 h. A receiver operator curve (ROC), decision plot analysis, and McNemar test of proportions were used to characterize the relationship between study variables. Results: Six hundred eighty six patients were enrolled, 23.2% (95% confidence interval [CI] 20.2-26.1) were diagnosed with PCP. The geometric mean CD4 count and ALC were 81 and 1089, respectively. The correlation between ALC and CD4 was r = 0.60 (95% CI 0.55-65, p < 0.01). The ROC was 0.78 (0.75-0.82). An ALC < 1700 cells/mm3 had a sensitivity of 84% (95% CI 80-87) and specificity of 55% (95% CI 48-70) for a CD4 < 200 cells/mm3. An ALC threshold of 1700 cells/mm3 would have identified 86% of patients with PCP but falsely identified 2.5 patients without PCP for every one accurately identified. Conclusion: The ALC threshold of 1700 cells/mm3 retains significant discriminatory value and would moderately improve identification of patients with a CD4 < 200 cells/mm3 but is not likely to be reliable as the sole method of early recognition and evaluation of PCP.

Original languageEnglish (US)
Pages (from-to)28-35
Number of pages8
JournalJournal of Emergency Medicine
Volume44
Issue number1
DOIs
StatePublished - Jan 1 2013
Externally publishedYes

Fingerprint

Pneumocystis Pneumonia
Lymphocyte Count
CD4 Lymphocyte Count
Hospital Emergency Service
Pneumonia
HIV
Pneumocystis carinii
Confidence Intervals
Decision Support Techniques
International Classification of Diseases
Immunosuppression

Keywords

  • absolute lymphocyte count
  • CD4
  • human immunodeficiency virus
  • PCP
  • pneumocystis pneumonia

ASJC Scopus subject areas

  • Emergency Medicine

Cite this

Use of the relationship between absolute lymphocyte count and CD4 count to improve earlier consideration of pneumocystis pneumonia in HIV-positive emergency department patients with pneumonia. / Napoli, Anthony M.; Maughan, Brandon; Murray, Ryan; Maloy, Kevin; Milzman, David.

In: Journal of Emergency Medicine, Vol. 44, No. 1, 01.01.2013, p. 28-35.

Research output: Contribution to journalArticle

@article{44a1ab93f3e74075a4ba3044950396b0,
title = "Use of the relationship between absolute lymphocyte count and CD4 count to improve earlier consideration of pneumocystis pneumonia in HIV-positive emergency department patients with pneumonia",
abstract = "Background: The ability to accurately assess the level of immunosuppression in HIV+ patients in the emergency department (ED) is often limited and can affect management of these patients. Objective: To evaluate the relationship between the absolute lymphocyte count (ALC) and CD4 count in HIV patients admitted through the ED with pneumonia and how utilization of this relationship may affect early consideration and evaluation of Pneumocystis jiroveci pneumonia (PCP). Methods: Retrospective multicenter 5-year study of HIV+ patients with an ICD-9 diagnosis of pneumonia. Included patients had an ALC measured on ED presentation and a CD4 count measured in < 24 h. A receiver operator curve (ROC), decision plot analysis, and McNemar test of proportions were used to characterize the relationship between study variables. Results: Six hundred eighty six patients were enrolled, 23.2{\%} (95{\%} confidence interval [CI] 20.2-26.1) were diagnosed with PCP. The geometric mean CD4 count and ALC were 81 and 1089, respectively. The correlation between ALC and CD4 was r = 0.60 (95{\%} CI 0.55-65, p < 0.01). The ROC was 0.78 (0.75-0.82). An ALC < 1700 cells/mm3 had a sensitivity of 84{\%} (95{\%} CI 80-87) and specificity of 55{\%} (95{\%} CI 48-70) for a CD4 < 200 cells/mm3. An ALC threshold of 1700 cells/mm3 would have identified 86{\%} of patients with PCP but falsely identified 2.5 patients without PCP for every one accurately identified. Conclusion: The ALC threshold of 1700 cells/mm3 retains significant discriminatory value and would moderately improve identification of patients with a CD4 < 200 cells/mm3 but is not likely to be reliable as the sole method of early recognition and evaluation of PCP.",
keywords = "absolute lymphocyte count, CD4, human immunodeficiency virus, PCP, pneumocystis pneumonia",
author = "Napoli, {Anthony M.} and Brandon Maughan and Ryan Murray and Kevin Maloy and David Milzman",
year = "2013",
month = "1",
day = "1",
doi = "10.1016/j.jemermed.2012.05.001",
language = "English (US)",
volume = "44",
pages = "28--35",
journal = "Journal of Emergency Medicine",
issn = "0736-4679",
publisher = "Elsevier USA",
number = "1",

}

TY - JOUR

T1 - Use of the relationship between absolute lymphocyte count and CD4 count to improve earlier consideration of pneumocystis pneumonia in HIV-positive emergency department patients with pneumonia

AU - Napoli, Anthony M.

AU - Maughan, Brandon

AU - Murray, Ryan

AU - Maloy, Kevin

AU - Milzman, David

PY - 2013/1/1

Y1 - 2013/1/1

N2 - Background: The ability to accurately assess the level of immunosuppression in HIV+ patients in the emergency department (ED) is often limited and can affect management of these patients. Objective: To evaluate the relationship between the absolute lymphocyte count (ALC) and CD4 count in HIV patients admitted through the ED with pneumonia and how utilization of this relationship may affect early consideration and evaluation of Pneumocystis jiroveci pneumonia (PCP). Methods: Retrospective multicenter 5-year study of HIV+ patients with an ICD-9 diagnosis of pneumonia. Included patients had an ALC measured on ED presentation and a CD4 count measured in < 24 h. A receiver operator curve (ROC), decision plot analysis, and McNemar test of proportions were used to characterize the relationship between study variables. Results: Six hundred eighty six patients were enrolled, 23.2% (95% confidence interval [CI] 20.2-26.1) were diagnosed with PCP. The geometric mean CD4 count and ALC were 81 and 1089, respectively. The correlation between ALC and CD4 was r = 0.60 (95% CI 0.55-65, p < 0.01). The ROC was 0.78 (0.75-0.82). An ALC < 1700 cells/mm3 had a sensitivity of 84% (95% CI 80-87) and specificity of 55% (95% CI 48-70) for a CD4 < 200 cells/mm3. An ALC threshold of 1700 cells/mm3 would have identified 86% of patients with PCP but falsely identified 2.5 patients without PCP for every one accurately identified. Conclusion: The ALC threshold of 1700 cells/mm3 retains significant discriminatory value and would moderately improve identification of patients with a CD4 < 200 cells/mm3 but is not likely to be reliable as the sole method of early recognition and evaluation of PCP.

AB - Background: The ability to accurately assess the level of immunosuppression in HIV+ patients in the emergency department (ED) is often limited and can affect management of these patients. Objective: To evaluate the relationship between the absolute lymphocyte count (ALC) and CD4 count in HIV patients admitted through the ED with pneumonia and how utilization of this relationship may affect early consideration and evaluation of Pneumocystis jiroveci pneumonia (PCP). Methods: Retrospective multicenter 5-year study of HIV+ patients with an ICD-9 diagnosis of pneumonia. Included patients had an ALC measured on ED presentation and a CD4 count measured in < 24 h. A receiver operator curve (ROC), decision plot analysis, and McNemar test of proportions were used to characterize the relationship between study variables. Results: Six hundred eighty six patients were enrolled, 23.2% (95% confidence interval [CI] 20.2-26.1) were diagnosed with PCP. The geometric mean CD4 count and ALC were 81 and 1089, respectively. The correlation between ALC and CD4 was r = 0.60 (95% CI 0.55-65, p < 0.01). The ROC was 0.78 (0.75-0.82). An ALC < 1700 cells/mm3 had a sensitivity of 84% (95% CI 80-87) and specificity of 55% (95% CI 48-70) for a CD4 < 200 cells/mm3. An ALC threshold of 1700 cells/mm3 would have identified 86% of patients with PCP but falsely identified 2.5 patients without PCP for every one accurately identified. Conclusion: The ALC threshold of 1700 cells/mm3 retains significant discriminatory value and would moderately improve identification of patients with a CD4 < 200 cells/mm3 but is not likely to be reliable as the sole method of early recognition and evaluation of PCP.

KW - absolute lymphocyte count

KW - CD4

KW - human immunodeficiency virus

KW - PCP

KW - pneumocystis pneumonia

UR - http://www.scopus.com/inward/record.url?scp=84872354047&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84872354047&partnerID=8YFLogxK

U2 - 10.1016/j.jemermed.2012.05.001

DO - 10.1016/j.jemermed.2012.05.001

M3 - Article

VL - 44

SP - 28

EP - 35

JO - Journal of Emergency Medicine

JF - Journal of Emergency Medicine

SN - 0736-4679

IS - 1

ER -