Table 2. Resultsa of micro-immunofluorescence (MIF) testsb of patients who are positive for R. rickettsii IgG or IgM by indirect immunofluorescence antibody assay (IFA) testsc.
| IFA IgG IFA IgM | MIF IgG | MIF IgM | |||||||||||
| SFGR | SFGR | TGR | SFGR | TGR | |||||||||
| Clinical final diagnosisd | R. rickettsia | R. rickettsii | R. conorii | R. japonica | R. felis | R. typhi | R. rickettsii | R. conorii | R. japonica | R. felis | R. typhi | ||
| Acute infection of SFGR | |||||||||||||
| Case 1 | UFD | 0/80 | 0/0 | 0/32 | 0/128 | 0/128 | 0/256 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 2 | UFD | 40/320 | 0/160 | 0/1024 | 0/1024 | 0/2048 | 0/4096 * | 0/0 | 0/128 | 0/32 | 0/0 | 0/256 * | 0/0 |
| Case 3 | Q fever | 0/160 | 0/0 | 0/64 | 0/64 | 0/64 | 0/256 * | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 4 | Scrub typhus | 80/640 | 0/0 | 128/512 | 512/512 | 256/256 | 1024/4096 * | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 5 | UFD | 0/640 | 0/0 | 0/512 | 0/2048 | 0/2048 | 0/4096 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Past infection of SFGR | |||||||||||||
| Case 6 | UFD | 80/80 | 0/0 | 0/0 | 32/32 | 32/32 | 32/32 | 0/32 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 7 | UFD | 0/80 | 0/0 | 32/0 | 0/0 | 0/0 | 0/32 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 8 | UFD | 0/80 | 0/0 | 0/0 | 0/0 | 0/0 | 0/32 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 9 | UFD | 40/80 | 0/0 | 32/32 | 32/32 | 32/64 | 128/64 * | 32/64 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 10 | Q fever | 160/640 | 0/0 | 32/32 | 0/32 | 0/32 | 128/128 * | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 11 | Scrub typhus | 0/40 | 0/0 | 0/32 | 0/64 | 64/64 | 128/256 * | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 12 | Q fever | 0/40 | 0/0 | 32/64 | 0/0 | 0/0 | 32/64 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 13 | Q fever | 40/40 | 0/0 | 32/32 | 64/64 | 64/64 | 128/128 | 32/32 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 14 | Leptospirosis | 0/160 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 15 | UFD | 40/80 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 16 | UFD | 80/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 17 | UFD | 80/80 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
| Case 18 | Scrub typhus | 40/80 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 |
a
Presentation of antibody titers: acute phase titer/convalescent phase titer.
b
Customized micro-immunofluorescence assay (Rickettsia screen IFA IgG and IgM antibody kit, Fuller Laboratories, USA).
c
Indirect immunofluorescence antibody assay (Rickettsia IFA IgG and IgM, Focus Diagnostic, USA).
*Considered as the representative pathogen of infection.
SFGR = Spotted fever group rickettsiae; TGR = Typhus group rickettsiae; UFD = Unknown febrile disease.