Cyclin-dependent kinase 4 expression alters the number of keratinocyte stem cells in the mouse hair follicle.

Hair follicles regenerate periodically by spontaneously undergoing cycles of growth, regression, and relative quiescence. During the hair cycle, follicle stem cells residing in a specialized niche remain quiescent, and they are stimulated to proliferate throughout the growth phase of the hair follicle. Although cell cycle regulators play a prominent role during the activation of hair follicle stem cells, the identity and the role of these regulators have not been confirmed. Herein, we reported that stem cells located in the bulge region of the HF (BuSCs) express high levels of cyclin-dependent kinase 4 (CDK4) through the quiescent phase of the hair cycle. Using gain- and loss-of-function studies, we have determined that the CDK4 protein level affects the number of BuSCs. Transgenic expression of CDK4 in the bulge region of the hair follicles reduces the number of BuSCs, whereas CDK4 ablation resulted in an increasing number of BuSCs. These results suggest that deregulation of CDK4 protein levels contributes to distorting the self-renewal/proliferation balance and, in turn, altering the number of BuSCs.

Phenformin Promotes Keratinocyte Differentiation via the Calcineurin/NFAT Pathway.

Phenformin is a drug in the biguanide class that was previously used to treat type 2 diabetes. We have reported the antitumor activities of phenformin to enhance the efficacy of BRAF-MAPK kinase-extracellular signal-regulated kinase pathway inhibition and to inhibit myeloid-derived suppressor cells in various melanoma models. Here we demonstrate that phenformin suppresses tumor growth and promotes keratinocyte differentiation in the 7,12-dimethylbenz[a]anthracene/12-O-tetradecanoylphorbol-13-acetate two-stage skin carcinogenesis mouse model. Moreover, phenformin enhances the suspension-induced differentiation of mouse and human keratinocytes. Mechanistically, phenformin induces the nuclear translocation of NFATc1 in keratinocytes in an AMPK-dependent manner. Pharmacologic or genetic inhibition of calcineurin and NFAT signaling reverses the effects of phenformin on keratinocyte differentiation. Taken together, our study reveals an antitumor activity of phenformin to promote keratinocyte differentiation that warrants future translational efforts to repurpose phenformin for the treatment of cutaneous squamous cell carcinomas.

The Sentinel Lymph Node Biopsy Using Indocyanine Green Fluorescence Plus Radioisotope Method Compared With the Radioisotope-Only Method for Breast Cancer Patients After Neoadjuvant Chemotherapy: A Prospective, Randomized, Open-Label, Single-Center Phase 2 Trial.

BACKGROUND: This study aimed to compare the sentinel lymph node (SLN) identification rates for breast cancer patients after neoadjuvant chemotherapy (NAC) between the dual method (DM) of indocyanine green fluorescence (ICG-F) plus a radioisotope (RI) and RI alone. METHODS: This randomized study enrolled 130 patients who received NAC for breast cancer and 122 patients who received SLN biopsy (SLNB) using either DM (n = 58) or RI only (n = 64). The study compared the identification rate, number of SLNs, and detection time of SLNB. RESULTS: Among the 122 patients, 113 (92.6%) were clinically node-positive before NAC. The SLN identification rate was 98.3% in the DM group and 93.8% in the RI group (p = 0.14). The DM group and the RI group were similar in the average number of SLNs (2.2 ± 1.13 vs. 1.9 ± 1.33; p = 0.26) and the time to detection of the first SLN (8.7 ± 4.98 vs. 8.3 ± 4.31 min; p = 0.30). In the DM group, transcutaneous lymphatic drainage was visualized by fluorescence imaging for 65.5% (38 of 58) of the patients. The SLN identification rate was 94.7% using ICG-F and 93% using RI (p = 0.79). During and after the operation, no complications, including allergic reactions or skin necrosis, occurred. CONCLUSIONS: This study is the first randomized trial to use ICG-F for SLNB in breast cancer patients after NAC. The DM including ICG-F could be a feasible and safe method for SLNB in initially node-positive breast cancer patients with NAC.

Characterization of hair-follicle side population cells in mouse epidermis and skin tumors.

A subset of cells, termed side-population (SP), which have the ability to efflux Hoeschst 33342, have previously been demonstrated to act as a potential method to isolate stem cells. Numerous stem/progenitor cells have been localized in different regions of the mouse hair follicle (HF). The present study identified a SP in the mouse HF expressing the ABCG2 transporter and MTS24 surface marker. These cells are restricted to the upper isthmus of the HF and have previously been described as progenitor cells. Consistent with their SP characteristic, they demonstrated elevated expression of ABCG2 transporter, which participates in the dye efflux. Analysis of tumor epidermal cell lines revealed a correlation between the number of SP keratinocytes and the grade of malignancy, suggesting that the SP may play a role in malignant progression. Consistent with this idea, the present study observed an increased number of cells expressing ABCG2 and MTS24 in chemically induced skin tumors and skin tumor cell lines. This SP does not express the CD34 surface marker detected in the multipotent stem cells of the bulge region of the HF, which have been defined as tumor initiation cells. The present study concluded that a SP with properties of progenitor cells is localized in the upper isthmus of the HF and is important in mouse skin tumor progression.

Cyclin D3 deficiency inhibits skin tumor development, but does not affect normal keratinocyte proliferation.

Rearrangement and amplification of the D-type cyclin genes have been reported in human cancer. Previous studies have demonstrated that Ras-mediated skin tumorigenesis depends on pathways that act through cyclin D1 and D2; however, the role of cyclin D3 remains unknown. The present study demonstrates that cyclin D3 ablation does not affect keratinocyte proliferation, but instead increases apoptosis levels in the bulge region of the hair follicle. Consequently, cyclin D3 ablation reduces skin papilloma development in a Ras-dependent carcinogenesis model. Previous results revealed that cyclin D3 preferentially binds to cyclin-dependent kinase 6 (CDK6) in mouse keratinocytes and transgenic expression of CDK6 (K5CDK6 mice) inhibits skin tumor development. Thus, we hypothesized that the inhibitory effect of CDK6 is dependent on cyclin D3 expression. To test this hypothesis, a mouse model that overexpresses CDK6 and does not express cyclin D3 (K5CDK6/cyclin D3-/- compound mouse) was developed. Biochemical analysis of the epidermis of K5CDK6/cyclin D3-/- mice revealed that cyclin D3 ablation resulted in increased expression of cyclin D1 protein, with a consequent elevation in the level of CDK6/cyclin D1 and CDK4/cyclin D1 complexes. These findings were concurrent with the increase skin papilloma malignant progression observed in K5CDK6/cyclin D3-/- mice. In summary the absence of cyclin D3 led to fewer number of papillomas in cyclin D3-ablated mice than in the wild-type owing to increased apoptosis, suggesting that alterations in cell survival are a crucial mechanism for crippling cellular defense against neoplasia. The results of the current study also suggest that although cyclin D3 expression does not alter the tumor suppressive role of CDK6 in skin carcinogenesis, the compensatory increase in cyclin D1 can shift the balance towards malignant progression.

Phenformin Inhibits Myeloid-Derived Suppressor Cells and Enhances the Anti-Tumor Activity of PD-1 Blockade in Melanoma.

Biguanides, such as the diabetes therapeutics metformin and phenformin, have shown antitumor activity both in vitro and in vivo. However, their potential effects on the tumor microenvironment are largely unknown. Here we report that phenformin selectively inhibits granulocytic myeloid-derived suppressor cells in spleens of tumor-bearing mice and ex vivo. Phenformin induces production of reactive oxygen species in granulocytic myeloid-derived suppressor cells, whereas the antioxidant N-acetylcysteine attenuates the inhibitory effects of phenformin. Co-treatment of phenformin enhances the effect of anti-PD-1 antibody therapy on inhibiting tumor growth in the BRAF V600E/PTEN-null melanoma mouse model. Combination of phenformin and anti PD-1 cooperatively induces CD8+ T-cell infiltration and decreases levels of proteins that are critical for immune suppressive activities of myeloid-derived suppressor cells. Our findings show a selective, inhibitory effect of phenformin on granulocytic myeloid-derived suppressor cell-driven immune suppression and support that phenformin improves the anti-tumor activity of PD-1 blockade immunotherapy in melanoma.

Targeting Stromal Glutamine Synthetase in Tumors Disrupts Tumor Microenvironment-Regulated Cancer Cell Growth.

Reactive stromal cells are an integral part of tumor microenvironment (TME) and interact with cancer cells to regulate their growth. Although targeting stromal cells could be a viable therapy to regulate the communication between TME and cancer cells, identification of stromal targets that make cancer cells vulnerable has remained challenging and elusive. Here, we identify a previously unrecognized mechanism whereby metabolism of reactive stromal cells is reprogrammed through an upregulated glutamine anabolic pathway. This dysfunctional stromal metabolism confers atypical metabolic flexibility and adaptive mechanisms in stromal cells, allowing them to harness carbon and nitrogen from noncanonical sources to synthesize glutamine in nutrient-deprived conditions existing in TME. Using an orthotopic mouse model for ovarian carcinoma, we find that co-targeting glutamine synthetase in stroma and glutaminase in cancer cells reduces tumor weight, nodules, and metastasis. We present a synthetic lethal approach to target tumor stroma and cancer cells simultaneously for desirable therapeutic outcomes.

Loss of cohesin complex components STAG2 or STAG3 confers resistance to BRAF inhibition in melanoma.

The protein kinase B-Raf proto-oncogene, serine/threonine kinase (BRAF) is an oncogenic driver and therapeutic target in melanoma. Inhibitors of BRAF (BRAFi) have shown high response rates and extended survival in patients with melanoma who bear tumors that express mutations encoding BRAF proteins mutant at Val600, but a vast majority of these patients develop drug resistance. Here we show that loss of stromal antigen 2 (STAG2) or STAG3, which encode subunits of the cohesin complex, in melanoma cells results in resistance to BRAFi. We identified loss-of-function mutations in STAG2, as well as decreased expression of STAG2 or STAG3 proteins in several tumor samples from patients with acquired resistance to BRAFi and in BRAFi-resistant melanoma cell lines. Knockdown of STAG2 or STAG3 expression decreased sensitivity of BRAF(Val600Glu)-mutant melanoma cells and xenograft tumors to BRAFi. Loss of STAG2 inhibited CCCTC-binding-factor-mediated expression of dual specificity phosphatase 6 (DUSP6), leading to reactivation of mitogen-activated protein kinase (MAPK) signaling (via the MAPKs ERK1 and ERK2; hereafter referred to as ERK). Our studies unveil a previously unknown genetic mechanism of BRAFi resistance and provide new insights into the tumor suppressor function of STAG2 and STAG3.

Comparison of targeted next-generation sequencing with conventional sequencing for predicting the responsiveness to epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) therapy in never-smokers with lung adenocarcinoma.

PURPOSE: To investigate the clinical utility of targeted next-generation sequencing (NGS) for predicting the responsiveness to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) therapy, we compared the efficacy with conventional sequencing in never-smokers with lung adenocarcinoma (NSLAs). PATIENTS AND METHODS: We obtained DNA from 48 NSLAs who received gefitinib or erlotinib for their recurrent disease after surgery. Sanger sequencing and peptide nucleic acid clamp polymerase chain reaction (PCR) were used to analyze EGFR, KRAS, BRAF, and PIK3CA mutations. We analyzed ALK, RET, and ROS1 rearrangements by fluorescent in situ hybridization or reverse transcriptase-PCR and quantitative real-time PCR. After molecular screening, Ion Torrent NGS was performed in 31 cases harboring only EGFR exon 19 deletions (19DEL), an L858R mutation, or none of the above mutations. RESULTS: The 31 samples were divided into four groups: (1) responders to EGFR-TKIs with only 19DEL or L858R (n=15); (2) primary resistance to EGFR-TKI with only 19DEL or L858R (n=4); (3) primary resistance to EGFR-TKI without any mutations (n=8); (4) responders to EGFR-TKI without any mutations (n=4). With NGS, all conventionally detected mutations were confirmed except for one L858R in group 2. Additional uncovered predictive mutations with NGS included one PIK3CA E542K in group 2, two KRAS (G12V and G12D), one PIK3CA E542K, one concomitant PIK3CA and EGFR L858R in group 3, and one EGFR 19DEL in group 4. CONCLUSIONS: Targeted NGS provided a more accurate and clinically useful molecular classification of NSLAs. It may improve the efficacy of EGFR-TKI therapy in lung cancer.

Isolation and characterization of a stem cell side-population from mouse hair follicles.

The mouse skin is composed of at least three differentiating epithelial compartments: the epidermis, the hair follicle, and the associated glands such as the sebaceous glands. Proliferation of these epithelial cells takes place in the keratinocytes' layer or basal cell layer; in the periphery of the sebaceous gland (the basal layer of the gland) and in specific cell compartments around the hair follicle. In mouse skin, an epithelial stem cell population is thought to localize to the bulge region of the hair follicle, a segment that does not undergo regression during the hair cycle. In addition, several other putative stem cells and/or progenitors have been identified in different regions of the hair follicle. Using the Hoeschst exclusion technique, originally described in the hematopoietic system, it has been possible to isolate a mouse keratinocyte cell population with characteristics of stem cells (side-population, SP). One of the main features of these SP is their ability to efflux antimitotic drugs as well as some specific dyes. This characteristic allows for SP cells to be isolated based upon their capacity to efflux the dye Hoechst 33342, through a mechanism driven by a membrane transporter, the breast cancer resistance protein (BCRP1/ABCG2). In this chapter, we described the isolation of SP stem cells from adult mouse hair follicles utilizing the Hoeschst exclusion technique by flow cytometry analysis.

Effects of ultrasonic pretreatment on quantity and composition of bacterial DNA recovered from granular activated carbon used for drinking water treatment.

Effects of ultrasonic pretreatment on bacterial DNA recovery from granular activated carbon (GAC) were investigated. GAC (Calgon F400), biologically activated, was sampled from an actual drinking water plant. Different ultrasonic energy densities (0-400 J·cm(-3)) were applied with agitation (250 rpm for 30 min), and recovered bacterial DNA was quantified using quantitative PCR. Energy density was linearly correlated with the concentration of carbon fines produced from GAC during ultrasonication. Ultrasonication alone had no effect on DNA recovery at ≤60 J·cm(-3), but a strongly adverse effect at >67 J·cm(-3) due to the produced carbon fines. Agitation along with ultrasonication strongly enhanced the bacterial DNA recovery when ≤40 J·cm(-3) was applied, although it did not affect the production of carbon fines. Ribosomal tag pyrosequencing was used to compare recovered bacterial communities (0, 20 and 30 J·cm(-3) with or without agitation). Ultrasonication allowed for obtaining a more diverse and richer bacterial community from GAC, compared with the control. Agitation did not show a positive effect on community organization (richness and diversity). Consistently, canonical correspondence analysis indicated that the energy density was associated with the relative abundances of particular bacterial members (P < 0.05), while agitation did not. Correspondence analysis revealed that the recovered bacterial communities were grouped according to the applied energy densities. In conclusion, ultrasonication and agitation influence the recovered DNA in quality and quantity, respectively, and carbon fines as a by-product by ultrasonication interfere with the DNA recovery.

Skp2 deficiency inhibits chemical skin tumorigenesis independent of p27(Kip1) accumulation.

S-phase kinase-associated protein 2 (Skp2) functions as the receptor component of the Skp-Cullin-F-box complex and is implicated in the degradation of several cell cycle regulators, such as p21(Cip1), p27(Kip1), p57(Kip2), and cyclin E. Numerous studies in human and experimental tumors have demonstrated low p27(Kip1) levels and elevated Skp2 expression. However, a direct association between the inverse correlation of Skp2 and p27(Kip1) with tumorigenesis has not been demonstrated. Herein, we provide evidence that skin tumorigenesis is inhibited in Skp2(-/-) mice. An analysis of mouse keratinocytes indicates that increased p27(Kip1) levels in Skp2(-/-) epidermis cause reduced cell proliferation that is alleviated in the epidermis from Skp2(-/-)/p27(-/-) compound mice. In contrast, we establish that a p27(Kip1) deficiency does not overturn the reduced skin tumorigenesis experienced by Skp2(-/-) mice. In addition, Skp2(-/-) epidermis exhibits an accumulation of p53-cofactor CBP/p300 that is associated with elevated apoptosis in hair follicles and decreased skin tumorigenesis. We conclude that p27(Kip1) accumulation is responsible for the hypoplasia observed in normal tissues of Skp2(-/-) mice but does not have a preponderant function in reducing skin tumorigenesis.

Early neutrophil-to-lymphocyte ratio reduction as a surrogate marker of prognosis in never smokers with advanced lung adenocarcinoma receiving gefitinib or standard chemotherapy as first-line therapy.

PURPOSE: An inflammatory-immunological marker, neutrophil-to-lymphocyte ratio (NLR), was evaluated as a surrogate indicator for prognosis of advanced lung adenocarcinoma patients. METHODS: The subjects of this study were 199 never smokers with advanced lung adenocarcinoma, who were enrolled in a prospective randomized phase III study (First-SIGNAL) comparing gefitinib with gemcitabine plus cisplatin as first-line therapy. The values of NLR were assessed at two time points: at baseline (pretreatment) and on day 1 of the second cycle (posttreatment). RESULTS: A higher posttreatment NLR was associated with a worse tumor response (median posttreatment NLR, 1.56 for partial response, 1.64 for stable disease, and 2.70 for progressive disease; P < 0.001). The risk of progression was higher when the posttreatment NLR was higher [hazard ratio (HR) = 1.23, 95 % confidence interval (CI) 1.15-1.31; P < 0.001]. A high posttreatment NLR was associated with an increased risk of death (HR = 1.13, 95 % CI 1.06-1.21; P < 0.001). These associations did not differ according to treatment arms. When total patients were divided into four groups according to the cutoff points of pre- and posttreatment NLRs, those with a high pretreatment NLR that declined substantially after treatment showed improved survival compared with those with a high pretreatment NLR that remained high even after treatment (median overall survival, 22.0 and 15.8 months, respectively; P < 0.001). CONCLUSIONS: A high posttreatment NLR is associated with poor prognosis. An early reduction in the NLR after effective treatment may indicate survival improvement in the patients with poor prognosis.

Efficacy of exemestane after nonsteroidal aromatase inhibitor use in metastatic breast cancer patients.

BACKGROUND: Previous studies have suggested a lack of complete cross-resistance between steroidal (exemestane) and non-steroidal aromatase inhibitors (nSAI). METHODS: Eighty-eight metastatic breast cancer (MBC) patients who received 25 mg of exemestane orally once a day at the National Cancer Center, Korea, between 2003 and 2009, were reviewed retrospectively. All patients had received nSAI for metastatic disease prior to exemestane therapy. RESULTS: The median age was 52 years (range, 33-79), and 13 (14.8%) patients were premenopausal who concomitantly received GnRH agonist. Exemestane was given as a second- (80.7%) or third-line (19.3%) hormone therapy. The clinical benefit (CB) rate (complete response + partial response + stable disease ≥ 24 weeks) was 30.7%, with a median CB duration of 10.0 months (range, 6.3-78.7). The median progression-free survival (PFS) was 3.0 months (95% confidence interval [CI], 1.99-4.01) and the overall survival (OS) 21.5 months (95% CI, 17.96-25.04), with a median follow-up of 50.3 months. Patients who achieved CB had longer OS than those patients who did not (29.6 vs 17.9 months; P = 0.002). On univariate analysis of predictive factors, patients who had achieved CB from previous nSAI tended to show lower CB rate (24.6% vs 44.4%, respectively; P = 0.063) and shorter PFS (2.8 vs 4.8 months, respectively; p = 0.233) than patients who had not. Achieving CB from previous nSAI became independent predictive factor for CBR to exemestane on multivariable analysis (Odds ratio = 2.852, P = 0.040). CONCLUSIONS: Exemestane after nSAI failure was effective in prolonging CB duration. The drug's efficacy seemed to be inferior in patients who had benefit from previous nSAI use.

Development and evaluation of a food frequency questionnaire for Vietnamese female immigrants in Korea: the Korean Genome and Epidemiology Study (KoGES).

The objectives of this study were to develop a food-frequency questionnaire (FFQ) for Vietnamese female immigrants in Korea and to evaluate the validity of the FFQ. A total of 80 food items were selected in developing the FFQ according to consumption frequency, the contribution of energy and other nutrients, and the cooking methods based on one-day 24 hour recall (24HR) from 918 Vietnamese female immigrants between November 2006 and November 2007. The FFQ was validated by comparison with 24HR of 425 Vietnamese female immigrants between November 2008 and August 2009. The absolute nutrient intake calculated from the FFQ was higher than that estimated by 24HR for most nutrients. The correlation coefficients between 24HR and FFQ ranged from 0.10 (vitamin C) - 0.36 (energy) for crude intake, 0.05 (vitamin E) - 0.32 (calcium) for per 1000 kcal, and 0.08 (zinc) - 0.34 (calcium) for energy-adjusted, respectively. More than 70% of subjects were classified into the same or adjacent agreement groups for nutrients other than fiber, sodium, vitamin A, vitamin C, and vitamin E, while less than 10% of subjects were classified into complete disagreement groups. We conclude that the FFQ appears to be an acceptable tool for estimating nutrient intake and dietary patterns of Vietnamese female immigrants in Korea. Future studies to validate the FFQ using various biomarkers or other dietary assessment methods are needed.

Dietary factors related to body weight in adult Vietnamese in the rural area of Haiphong, Vietnam: the Korean Genome and Epidemiology Study (KoGES).

The objectives of this study were to examine the association between dietary factors and underweight and overweight adult Vietnamese living in the rural areas of Vietnam. A cross-sectional study of 497 Vietnamese aged 19 to 60 years (204 males, 293 females) was conducted in rural areas of Haiphong, Vietnam. The subjects were classified as underweight, normal weight, and overweight based on BMI. General characteristics, anthropometric parameters, blood profiles, and eating habits were obtained and dietary intake was assessed using 24-hour recalls for 2 consecutive days. A high prevalence of both underweight (BMI < 18.5 kg/m(2)) and overweight (BMI >/= 23 kg/m(2)) individuals was observed (14.2% and 21.6% for males and 18.9% and 20.6% for females, respectively). For both genders, the overweight group were older than the under- and normal weight groups (P = 0.0118 for males and P = 0.0002 for females). In female subjects, the overweight group consumed significantly less cereals (P = 0.0033), energy (P = 0.0046), protein (P = 0.0222), and carbohydrate (P = 0.0017) and more fruits (P = 0.0026) than the underweight group; however, no such differences existed in males. The overweight subjects overate more frequently (P = 0.0295) and consumed fish (P = 0.0096) and fruits (P = 0.0083) more often. The prevalence of both underweight and overweight individuals pose serious public health problems in the rural areas of Vietnamese and the overweight group was related to overeating and high fish and fruit consumption. These findings may provide basic data for policymakers and dieticians in order to develop future nutrition and health programs for rural populations in Vietnam.

Psychological distress is associated with inadequate dietary intake in Vietnamese marriage immigrant women in Korea.

Previous studies have reported that the nutritional status of Vietnamese female marriage immigrants in Korea is inadequate. And the mediation of acculturation stress can contribute to problems in their eating practices and dietary intakes. This study examines an association between psychological distress and inadequate dietary intake in Vietnamese female marriage immigrants living in Korea. A cross-sectional study analyzed baseline data (n=570) from the Cohort of Intermarried Women in Korea. Daily nutrient intakes were compared according to the quartiles of distress scores assessed by the Psychological Well-Being Index-Short Form. One-way analysis of variance and chi(2) tests were used to compare eating practices and nutrient intake across quartiles of psychological distress. Subjects in the highest stress scores were more likely to skip breakfast and to change their dietary habits after living in Korea than those in groups with low stress scores. Analyses of the subjects' Mini Dietary Assessments revealed that those with the highest stress scores were less likely to consume milk or dairy products, eat regular meals, or have balanced diets than those with the lowest stress scores. Nutrient intakes were found to be inadequate in the subjects, and those with the highest stress scores showed lower consumptions of energy, carbohydrate, protein, fat, calcium, zinc, thiamin, riboflavin, and folate compared to those with the lowest scores. The prevalence of underweight (body mass index [calculated as kg/m(2)] <18.5) increased from the lowest to highest quartiles of psychological distress scores. Psychological distress in Vietnamese female marriage immigrants living in Korea was negatively associated with dietary intake. These findings can assist dietetics practitioners working with minority immigrants because such information is important in designing appropriate strategies for dietary counseling. A follow-up study should address the underlying mechanisms of the observed diet-distress association in Vietnamese marriage immigrant women in Korea, as well as other various ethnic minority immigrants in Korea.

Ascitic fluid infection in patients with hepatitis B virus-related liver cirrhosis: culture-negative neutrocytic ascites versus spontaneous bacterial peritonitis.

BACKGROUND AND AIM: Ascitic fluid infection (AFI) consists of culture-negative neutrocytic ascites (CNNA) and spontaneous bacterial peritonitis (SBP). The present study compared the clinical characteristics and prognosis of CNNA and SBP in hepatitis B virus (HBV)-related cirrhotic patients. METHODS: We analyzed 130 consecutive patients hospitalized due to the first episode of AFI between January 1998 and December 2007. RESULTS: The mean age of the patients was 52.3 years (88 men, 42 women). Ninety-three patients (71.5%) had CNNA and 37 patients (28.5%) had SBP; 117 patients (90.0%) died after a median survival period of 6.4 months. Patients with CNNA and SBP survived for a median period of 6.9 months and 5.4 months, respectively (P = 0.417). Patients with SBP showed higher in-hospital mortality than those with CNNA (16.2 vs 4.3%; P = 0.031). Binary logistic regression analysis showed that culture positivity of ascitic fluid (CNNA vs SBP) was the only independent predictor of in-hospital mortality (P = 0.042). In a Cox regression model for the 120 patients (92.3%) who survived the first episode of AFI, only the Child-Pugh score remained significant for survival (P = 0.007), whereas no association was observed for culture positivity of ascitic fluid (CNNA vs SBP) during the first episode of AFI (P = 0.752). CONCLUSIONS: Although in-hospital mortality was higher in patients with SBP than CNNA, the clinical course of the two groups was similar after the first episode of AFI. Thus, liver transplantation should be considered, irrespective of culture positivity of ascitic fluid.