| Background: It is difficult to find the causes of lots of patients with fever inclinical practice. Infectious disease is a major cause of fever, in which tuberculosisbacterium infection may take an important part in China. If other diseases aremisdiagnosed as tuberculosis (TB), the application of anti-TB drugs would result indamage to the liver and kidney of the patients. Once TB is misdiagnosed as otherdiseases, it may delay treatment. The application of hormone may lead todisseminated tuberculosis. Interms of current technology, it is hard to diagnose TBinfection in the patients with fever, especially the patients with ambiguous TB lesions.To avoid excessive or delayed treatment, diagnose and control of TB infection thesooner the better. In2008, T-SPOT.TB became the fourth Interferon-gamma releaseAssay (IGRA) certified by FDA. Many domestic and foreign researches suggest thatT-SPOT. TB has a high degree of sensitivity and specificity in the diagnosis ofactive tuberculosis and latent tuberculosis, but the sensitivity and specificity ofdiagnosing tuberculosis infection in patients with fever is rare reported.Objective: It is hard to diagnose TB infection in the patients with fever andambiguous TB lesions. IGRA has been widely used in clinic as a main method for thediagnosis of TB infection in recent years. In this study, we carried out T-SPOT. TBdetection in the patients with fever, and further assessed the diagnostic value ofT-SPOT.TB in those cases.Methods: T-SPOT.TB were carried out in456patients with fever, who cannotbe determined the reason for fever and excluded as TB infection after some inspection.We followed up these patients, inquired their diagnoses, then analyzed the followingdata and evaluated the diagnostic value of T-SPOT.TB using software SPSS17.0.Results:1. For456patients, there were203cases (44.5%) for T-SPOT.TB positive,232cases(50.9%) for T-SPOT.TB negative,21cases (4.6%) for T-SPOT.TB suspicious positive.2. In this study we also found there were more men than women in the positive group and that wether T-SPOT.TB is positive or not has nothing to do with active TBin the past.3. In the present study,85patients were diagnosed as TB infection (34cases ofpulmonary TB,24cases of TB infection,10cases of tuberculous pleurisy,17cases ofTB in other parts) and371patients without clear evidence of TB (42cases ofsuspected TB infection,329cases of other diseases).4. IGRA(T-SPOT.TB) has a high sensitivity of84.3%in TB cases group, and ahigh Negative Predictive Value of94.2%, but its specificity is68.1%and PositivePredictive Value is41.4%. The Kappa value was0.380and the area under the ROCcurve was0.762(95%CI:70.7%-81.7%). In patients with FUO, it’s also has a highsensitivity of85.5%in TB cases group, and a high Negative Predictive Value of90.9%, its specificity is60.6%and Positive Predictive Value is47.5%. The Kappavalue was0.373and the area under the ROC curve was0.730(95%CI:65.4%-80.6%).5. IGRA (T-SPOT. TB) has a higher sensitivity in extra-pulmonary TB thanpulmonary TB,88.2%versus78.1%. Their Negative Predictive Value were95.3%and92.6%, Kappa value were0.438and0.299, and the area under the ROC curvewere0.791(95%CI:72.4%-85.7%) and0.719(95%CI:62.3%-81.5%) respectively.6.99cases were T-SPOT.TB positive in329cases of other diseases.Conclusion:1. Whether IGRA is positive or not has nothing to do with active TB in the past.2. IGRA plays a critical role in excluding TB infection due to its high NegativePredictive Value.3. IGRA can be used as a method of diagnosis for TB infection and TB inpatients with fever and ambiguous TB lesions, especially forextra-pulmonary TB.4. Moreover, it is also helpful for those patients of latent TB infection who needregular follow-up. |
PDF Full Text Request