TY - JOUR
T1 - Brief Report
T2 - Real-World Performance and Interobserver Agreement of Urine Lipoarabinomannan in Diagnosing HIV-Associated Tuberculosis in an Emergency Center
AU - Van Hoving, Daniël J.
AU - Lahri, Saʼad
AU - Lategan, Hendrick J.
AU - Nicol, Mark P.
AU - Maartens, Gary
AU - Meintjes, Graeme
PY - 2019/5/1
Y1 - 2019/5/1
N2 - BACKGROUND: The urine lipoarabinomannan (LAM) lateral flow assay is a point-of-care test to diagnose HIV-associated tuberculosis (TB). We assessed the performance of urine LAM in HIV-positive patients presenting to the emergency center and evaluated the interobserver agreement between emergency center physicians and laboratory technologists. SETTING: A cross-sectional diagnostic study was performed at the emergency center of a district hospital in a high HIV-prevalence community in South Africa. METHODS: Consecutive HIV-positive adults presenting with ≥1 WHO TB symptom were enrolled over a 16-month period. A urine LAM test was performed at point-of-care by an emergency physician and interpreted independently by 2 physicians. A second test was performed in the laboratory and interpreted independently by 2 laboratory technologists. The reference standard was a positive TB culture or Xpert MTB/RIF test on sputum or appropriate extrapulmonary samples. We compared diagnostic accuracy and reproducibility of urine LAM between point-of-care readers and laboratory readers. RESULTS: One thousand three hundred eighty-eight samples (median, 3 samples/participant) were sent for TB microbiology tests in 411 participants; 170 had confirmed TB (41.4%). Point-of-care and laboratory-performed urine LAM had similar sensitivity (41.8% vs 42.0%, P = 1.0) and specificity (90.5% vs 87.5%, P = 0.23). Moderate agreement was found between point-of-care and laboratory testing (κ = 0.62), but there was strong agreement between point-of-care readers (κ = 0.95) and between laboratory readers (κ = 0.94). Positive percent agreement between point-of-care and laboratory readers was 68% and negative percent agreement 92%. CONCLUSION: There is no diagnostic accuracy advantage in laboratory-performed versus point-of-care-performed urine LAM tests in emergency care centers in high-burden settings.
AB - BACKGROUND: The urine lipoarabinomannan (LAM) lateral flow assay is a point-of-care test to diagnose HIV-associated tuberculosis (TB). We assessed the performance of urine LAM in HIV-positive patients presenting to the emergency center and evaluated the interobserver agreement between emergency center physicians and laboratory technologists. SETTING: A cross-sectional diagnostic study was performed at the emergency center of a district hospital in a high HIV-prevalence community in South Africa. METHODS: Consecutive HIV-positive adults presenting with ≥1 WHO TB symptom were enrolled over a 16-month period. A urine LAM test was performed at point-of-care by an emergency physician and interpreted independently by 2 physicians. A second test was performed in the laboratory and interpreted independently by 2 laboratory technologists. The reference standard was a positive TB culture or Xpert MTB/RIF test on sputum or appropriate extrapulmonary samples. We compared diagnostic accuracy and reproducibility of urine LAM between point-of-care readers and laboratory readers. RESULTS: One thousand three hundred eighty-eight samples (median, 3 samples/participant) were sent for TB microbiology tests in 411 participants; 170 had confirmed TB (41.4%). Point-of-care and laboratory-performed urine LAM had similar sensitivity (41.8% vs 42.0%, P = 1.0) and specificity (90.5% vs 87.5%, P = 0.23). Moderate agreement was found between point-of-care and laboratory testing (κ = 0.62), but there was strong agreement between point-of-care readers (κ = 0.95) and between laboratory readers (κ = 0.94). Positive percent agreement between point-of-care and laboratory readers was 68% and negative percent agreement 92%. CONCLUSION: There is no diagnostic accuracy advantage in laboratory-performed versus point-of-care-performed urine LAM tests in emergency care centers in high-burden settings.
UR - http://www.scopus.com/inward/record.url?scp=85064725970&partnerID=8YFLogxK
U2 - 10.1097/QAI.0000000000002002
DO - 10.1097/QAI.0000000000002002
M3 - Article
C2 - 30865176
AN - SCOPUS:85064725970
VL - 81
SP - e10-e14
JO - Journal of Acquired Immune Deficiency Syndromes and Human Retrovirology
JF - Journal of Acquired Immune Deficiency Syndromes and Human Retrovirology
SN - 1525-4135
IS - 1
ER -