Table 5.
Summary of studies evaluating DBS for bacteria
| Disease, assay type, and country | Ref. | Number of samples/filter paper type | Test | Sensitivity (%) | Specificity (%) | Notes |
|---|---|---|---|---|---|---|
| Leprosy serology | ||||||
| French Polynesia | 86 | 168 patients/ Whatman No.1 | In-house ELISA | Multibacillary 96; Paucibacillary 29 | Multibacillary 96; Paucibacillary 96 | |
| India | 87 | 94 patients/ Whatman No.3 | In-house ELISA | Multibacillary 97; Paucibacillary 73 | Multibacillary 100; Paucibacillary 100 | Based on a cutoff of 1:40 (OD) |
| India | 88 | 81 patients/ Whatman No.3 | MLPA (Fujirebio); in-house ELISA | 67.7 (MLPA); 76.9 (ELISA) | 98.7 (MLPA); 83.4 (ELISA); | |
| Nepal | 85 | 200 patients/ NR | In-house ELISA | NR | NR | Earlobe capillary blood more sensitive than serum or finger-prick blood85 |
| Orientia tsutsugamushi and Rickettsia typhi (scrub typhus and murine typhus) | ||||||
| Laos | 93 | 53 scrub typhus patients; 53 murine typhus patients/ Whatman 903 | In-house ELISA | 95 IgM and 90 IgG; 91 IgM and 82 IgG | 88 IgM and 100 IgG; 100 IgM and 100 IgG | Lower antibody titers with DBS; storage at room temperature for 1 month did not affect antibody titers93,94 |
| Coxiella burnetii, Bartonella quintana and Rickettsia conorii serology | ||||||
| France | 94 | 94 patients/ Fischer Scientific paper94 | In-house ELISA | 100 | 100 | |
| Leptospirosis serology (MAT) | ||||||
| La Reunion | 90 | 52 patients/ Whatman 903 | MAT | 100 | 100 | DBS samples showed lower antibody titers compared with serum |
| Syphilis serology | ||||||
| United States | 91 | 1,098 patients/ Whatman 903 | In-house ELISA | 96 | 94 | |
| Tanzania | 92 | 1,037 patients/ Whatman 903 | Serodia TPPA (Fujirebio) | 98.3 | 100 | |
| Yaws serology | ||||||
| Papua New Guinea | 95 | 70 patients/ Whatman 903 | TPHA–Serodia TP kit (Fujirebio) | 96.5 | 100 | Results unaffected by up to 2 months storage |
| Brucella serology | ||||||
| Spain | 89 | 160 patients/ Whatman 2992 | Brucella ELISA (Virotech System Diagnostika) | NR | NR | Pearson correlation coefficient: r = 0.8 for IgM and IgG; time-consuming extraction method |
MAT = microscopic agglutination test; MLPA = Mycobacterium leprae particle agglutination; TPHA = Treponema pallidum-specific hemagglutination test; TPPA = Treponema pallidum particle agglutination test.