Table 3. Clinical concurrent conditions and immunofluorescence and neutralization titers of patients with IgM-positive California serogroup virus infections in Finland, 2001–2013*.
| Patient no. | IgG IFA titer | IgM IFA titer | PCR result | Underlying illness | Reason for medical care | PRNT titer |
||
|---|---|---|---|---|---|---|---|---|
| INKV | CHATV | TAHV | ||||||
| 1 | 160 | 160 | Neg | – | Hospitalized (unknown infection)† | 320 | 40 | 40 |
| 2 | 80 | 40 | Neg | – | Hospitalized (unknown infection)† | 320 | 640‡ | 40 |
| 3 | 120 | 40 | Neg | – | Hospitalized (unknown infection)† | 320 | 40 | 40 |
| 4 | >640 | >320 | Neg | Hypertension | Hospitalized (unknown infection)† | 320 | 20,480 | 5,120 |
| 5§ | 160 | +/ND¶ | ND | – | Hospitalized (unknown infection)† | ND | ND | ND |
| 6§ | 320 | +/ND¶ | ND | – | Hospitalized (unknown infection)† | ND | ND | ND |
| 7 | 80 | >320 | Neg | Type 2 diabetes, hypertension | Fever (unknown infection)† | >640 | 40 | 80 |
| 8 | 320 | 40 | Neg | – | No information | 320 | <20 | <20 |
| 9 | 80 | 80 | Neg | Asthma, immunodeficiency | No information | 160 | 40 | <40 |
| 10 | 40 | 20 | ND | Hypothyroidism | Follow-up visit (suspected MS, neurologic disorder) | 160 | 20 | 40 |
| 11 | 320 | >320 | Neg | – | Follow-up visit (recurrent respiratory tract infections for 4 mo, suspected immunodeficiency) | 320 | 40 | 80 |
| 12 | <20 | 40 | Neg | Schizophrenia, hypothyroidism | Follow-up visit (HSV eye infection, rash, Steven-Johnson syndrome) | 320 | 20 | 40 |
| 13 | 160 | 120 | Neg | – | Hospitalized, acute infection (E. coli urosepsis) | 160 | 40 | 40 |
| 14 | <20 | 120 | Neg | MS disease, hypothyroidism | Hospitalized, acute infection (HSV infection) | >640 | <20 | 20 |
| 15 | 320 | 120 | Neg | – | Hospitalized, acute infection (impetigo contagiosa) | 640 | 40 | 40 |
| 16 | 960 | 40 | ND | – | Hospitalized, multiple infarcts in the central nervous system | 1,280 | 5,120 | 1,280 |
| 17 | 80 | 30 | Neg | – | Hospitalized, epidemic nephropathy | 320 | <20 | <20 |
*CHATV, Chatanga virus; HSV, herpes viruses; IFA, indirect immunofluorescence; INKV, Inkoo virus; MS, multiple sclerosis; ND, PCR not done; PRNT, plaque reduction neutralization test; TAHV, Tahyna virus; –, no underlying illness. †Full patient history describing INKV or CHATV infection. ‡4-fold difference between titers was not achieved with neutralization test, the diagnostic criterion used to confirm CHATV infection. §INKV infection confirmed by hemagglutination inhibition test and neutralization test earlier in Helsinki University Central Hospital laboratory. ¶Samples tested were IgM positive, but titer was not tested.