Prospective Evaluation of Procalcitonin, Soluble Triggering Receptor Expressed on Myeloid Cells-1 and C-Reactive Protein in Febrile Patients with Autoimmune Diseases.
BACKGROUND
Both procalcitonin (PCT) and soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) have been investigated separately as indicators of infection in patients with autoimmune diseases. Our study simultaneously evaluated both PCT and sTREM-1 along with C-reactive protein (CRP) in febrile patients with autoimmune diseases.


METHODS
Fifty-nine patients were enrolled in the study. The patients were categorized into the infection group (n=24) or the disease flare group (n=35). sTREM-1, PCT and CRP concentrations at fever onset were compared between the two groups of patients.


RESULTS
sTREM-1 and CRP did not differ between the two groups. PCT [median (range), ng/ml] was higher in the infection group than in the disease flare group [0.53 (0.02-12.85) vs. 0.12 (0.02-19.23), p=0.001]. The area under the receiver-operating characteristic (ROC) for diagnosis of infection was 0.75 for PCT (p=0.001), 0.63 for CRP (p=0.09) and 0.52 for sTREM-1 (p=0.79). Using 0.2 ng/ml as the cutoff value for PCT, sensitivity was 0.75 and specificity was 0.77. Negative predictive values for PCT were 92%, 87% and 82% for a prevalence of infection of 20%, 30%, and 40%, respectively. Neither immunosuppressants nor biomodulators affected the level of the three biomarkers. However, in patients treated with corticosteroids, the levels of sTREM-1 and CRP were significantly decreased compared with the untreated patients.


CONCLUSIONS
Setting PCT at a lower cutoff value could provide useful information on excluding infection in febrile patients with autoimmune diseases. The possible effect of corticosteroids on the level of sTREM-1 as an infection marker deserves further study.
Department of Internal Medicine, Far Eastern Memorial Hospital, New Taipei city, Taiwan.
Chou-Han
CH
Lin
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Song-Chou
SC
Hsieh
Department of Internal Medicine, National Taiwan University Hospital, Hsin-Chu Branch, Hsin-Chu, Taiwan.
Li-Ta
LT
Keng
Department of Internal Medicine, E-Da hospital, Kaoshiung, Taiwan.
Ho-Sheng
HS
Lee
Department of Internal Medicine, Far Eastern Memorial Hospital, New Taipei city, Taiwan.
Hou-Tai
HT
Chang
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Wei-Yu
WY
Liao
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Chao-Chi
CC
Ho
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Chong-Jen
CJ
Yu
D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D001327:Autoimmune Diseases / Q000097:blood* / Q000150:complications* / Q000188:drug therapy; D002097:C-Reactive Protein / Q000032:analysis*; D002116:Calcitonin / Q000097:blood*; D015740:Calcitonin Gene-Related Peptide; D005260:Female; D005334:Fever / Q000097:blood / Q000150:complications*; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008297:Male; D008562:Membrane Glycoproteins / Q000097:blood*; D008875:Middle Aged; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood*; D011971:Receptors, Immunologic / Q000097:blood*; D000073871:Triggering Receptor Expressed on Myeloid Cells-1
D000305:Adrenal Cortex Hormones; C000606589:CALCA protein, human; D007166:Immunosuppressive Agents; D008562:Membrane Glycoproteins; D011498:Protein Precursors; D011971:Receptors, Immunologic; C408842:TREM1 protein, human; D000073871:Triggering Receptor Expressed on Myeloid Cells-1; D002116:Calcitonin; D002097:C-Reactive Protein; D015740:Calcitonin Gene-Related Peptide