Table 4 Diagnostic sensitivity and specificity of a rapid cryptococcal antigen lateral flow assay (CrAg LFA), using either positive serum CrAg enzyme immunoassay (EIA) or positive latex agglutination as gold-standard test result.

From: Validation of clinic-based cryptococcal antigen lateral flow assay screening in HIV-infected adults in South Africa

 

#TP/(#TP + #FN)

Sensitivity% (95% CI)

#TN/(#TN + #FP)

Specificity% (95% CI)

Clinic-based venous whole blood CrAg LFA

All participants

9/23

39 (20, 61)

1,121/1,140

98 (97, 99)

CD4 < 200 cells/mm3

8/18

44 (22, 69)

311/318

98 (96, 99)

CD4 < 100 cells/mm3

5/11

45 (17, 77)

139/145

96 (91, 98)

Clinic-based fingerprick capillary blood CrAg LFA

All participants

6/23

26 (10, 48)

1,103/1,140

97 (96, 98)

CD4 < 200 cells/mm3

5/18

28 (10, 53)

306/316

97 (94, 98)

CD4 < 100 cells/mm3

3/11

27 (6, 61)

139/145

96 (91, 98)

Clinic-based urine CrAg LFA

All participants

9/23

39 (20, 61)

1,014/1,128

90 (88, 92)

CD4 < 200 cells/mm3

8/18

44 (22, 69)

268/313

86 (81, 89)

CD4 < 100 cells/mm3

4/11

36 (11, 69)

113/142

80 (72, 86)

  1. CI = confidence interval; CrAg = cryptococcal antigen; EIA = enzyme immunoassay; FN = false negative; FP = false positive; LFA = lateral flow assay; TN = true negative; TP = true positive.
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