Use of the delta neutrophil index as a prognostic factor of mortality in patients with spontaneous bacterial peritonitis: implications of a simple and useful marker.
BACKGROUND
Spontaneous bacterial peritonitis (SBP) is a common and life-threatening infection in patients with advanced cirrhosis. The prognostic value of a novel marker, the delta neutrophil index (DNI), was investigated relative to mortality in patients with SBP.


METHODS
Seventy-five patients with SBP were studied from April 2010 to May 2012. DNI at initial diagnosis of SBP was determined and compared with 30-day mortality rates.


RESULTS
Of the patients, 87.7% were men, and the median age of all patients was 59.0 yrs. The area under the receiver-operating characteristic (ROC) curve of DNI for 30-day mortality was 0.701 (95% confidence interval [CI], 0.553-0.849; p = 0.009), which was higher than that of C-reactive protein (0.640, 95% CI, 0.494-0.786; p = 0.076) or the model for end-stage liver disease score (0.592, 95% CI, 0.436-0.748; p = 0.235). From the ROC curve, with the sum of sensitivity and specificity, the cutoff value of DNI was determined to be 5.7%. In the high-DNI group (DNI ≥5.7%), septic shock and 30-day mortality were more prevalent compared with the low-DNI group (84.2% vs. 48.2%, p = 0.007; 57.9% vs. 14.3%, p<0.001, respectively). Patients with an elevated DNI had a higher risk of 30-day mortality compared with those with a low DNI (4.225, 95% CI, 1.631-10.949; p = 0.003).


CONCLUSIONS
A higher DNI at the time of SBP diagnosis is an independent predictor of 30-day mortality in patients with SBP.
Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea.
Tae Seop
TS
Lim
Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea ; Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Republic of Korea ; Liver Cirrhosis Clinical Research Center, Seoul, Republic of Korea.
Beom Kyung
BK
Kim
Department of Laboratory Medicine, Incheon Baek Hospital, Incheon, Republic of Korea.
Jong Wook
JW
Lee
Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea.
Young Ki
YK
Lee
Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea.
Sooyun
S
Chang
Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea ; Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Republic of Korea ; Liver Cirrhosis Clinical Research Center, Seoul, Republic of Korea.
Seung Up
SU
Kim
Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea ; Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Republic of Korea ; Liver Cirrhosis Clinical Research Center, Seoul, Republic of Korea.
Do Young
DY
Kim
Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea ; Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Republic of Korea ; Liver Cirrhosis Clinical Research Center, Seoul, Republic of Korea.
Sang Hoon
SH
Ahn
Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea ; Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Republic of Korea ; Liver Cirrhosis Clinical Research Center, Seoul, Republic of Korea.
Kwang-Hyub
KH
Han
Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea ; Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Republic of Korea ; Liver Cirrhosis Clinical Research Center, Seoul, Republic of Korea.
Chae Yoon
CY
Chon
Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea ; Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Republic of Korea ; Liver Cirrhosis Clinical Research Center, Seoul, Republic of Korea.
Jun Yong
JY
Park
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001424:Bacterial Infections / Q000382:microbiology / Q000401:mortality* / Q000473:pathology; D015415:Biomarkers / Q000032:analysis*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008103:Liver Cirrhosis / Q000382:microbiology / Q000401:mortality* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000473:pathology*; D010538:Peritonitis / Q000382:microbiology / Q000401:mortality* / Q000473:pathology; D011379:Prognosis; D012372:ROC Curve; D012189:Retrospective Studies; D015996:Survival Rate
D015415:Biomarkers