Early magnesium modifications as a surrogate marker of efficacy of cetuximab-based anticancer treatment in KRAS wild-type advanced colorectal cancer patients.

BACKGROUND: KRAS wild-type mutational status is necessary but not sufficient to get benefit from epidermal growth factor receptor inhibition. Predictive markers are currently being evaluated. In this study, we investigated early hypomagnesemia as a predictor of efficacy and outcome in terms of time to progression (TtP) and overall survival (OS) in a cohort of patients affected by advanced colorectal adenocarcinoma KRAS wild-type cetuximab-treated. PATIENTS AND METHODS: One hundred and forty-three patients affected by stage IV colorectal adenocarcinoma KRAS wild type receiving cetuximab + irinotecan (CTX+IRI) as third-line anticancer treatment and resistant to oxaliplatin- and irinotecan-based chemotherapy were retrospectively included. Magnesium plasma levels were measured before the first day and 7, 14, 21 and 28 days after CTX+IRI infusion. RESULTS: The median magnesium basal value showed a statistically significant decrease after the start of CTX+IRI treatment (at 28 days, P < 0.0001). Patients with an early decrease of magnesium levels >50% compared with the basal level had a higher tumor response rate (55.8% versus 16.7%, P < 0.0001), a longer TtP (6.3 versus 3.6, P < 0.0001) and a longer median OS (11.0 versus 8.1, P = 0.002). CONCLUSIONS: We have shown that early hypomagnesemia could be a predictor of efficacy and outcome in those patients. Magnesium circulating level is an easy and inexpensive biomarker to routinely be detected in patients treated with cetuximab.

Population structure of invasive Streptococcus pneumoniae isolates in Italy prior to the implementation of the 7-valent conjugate vaccine (1999-2003).

A total of 773 pneumococcal isolates were collected from a nationwide surveillance of invasive pneumococcal diseases during 1999-2003 prior to the implementation of the 7-valent conjugate vaccine (PCV7) in Italy. The isolates included vaccine serotypes (VS, 393 isolates), vaccine-related serotypes (VRS, 93), and nonvaccine serotypes (NVS, 279). The ten most prevalent serotypes were: 14 (16.4%), 3 (8.4%), 23F (8%), 19F (7.4%), 4 (5.9%), 7F (5.8%), 9V (5.3%), 6B (4.9%), 19A (4.7%), and 1 (3.7%). VRS or NVS isolates showed a lower rate of penicillin or drug resistance than VS. Representative isolates of the major VS, VRS, and NVS were genotyped by pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). The isolates examined were found to belong to 18 international clones and to eight newly described clones. VS isolates sharing clonal groups with VRS or NVS were also detected. Evidence of a past history of capsular switching events was observed in five clones.

Toll-like receptor 4 Asp299Gly and Thr399Ile polymorphisms in gastric cancer of intestinal and diffuse histotypes.

In the present study we investigated the potential role of Toll-like receptor 4 (TLR-4) Asp299Gly and Thr399Ile polymorphisms as risk factors in the development of gastric cancer. TLR-4 Asp299Gly and Thr399Ile polymorphisms were investigated in 171 Italian patients with sporadic gastric cancer and in 151 controls. Unconditional regression (odds ratio and 95% confidence intervals) were used to investigate the association of the studied polymorphisms with gastric cancer. TLR-4 Thr399Ile polymorphism is linked with an increased susceptibility to gastric cancer (P = 0.023 and hazard ratio = 3.62). No significant association for TLR-4 Asp299Gly polymorphism was found. In the subgroup of patients with intestinal-type gastric cancer, a significant risk of gastric cancer was associated with TLR-4 Thr399Ile genotype (P = 0.006). Our results demonstrated that TLR-4 Thr399Ile polymorphism is linked with an increased susceptibility to gastric cancer. An increased risk for intestinal gastric cancer in carriers of the TLR4 Thr399Ile allele was observed. Future epidemiological studies should consider the possible interactions between proinflammatory genotypes (such as TLR and interleukin-1R polymorphisms) and other risk factors for cancer such as dietary habits and/or exposure to environmental carcinogens.

Circulating substance P levels and shoulder joint contracture after arthroscopic repair of the rotator cuff.

OBJECTIVE: To determine the plasma levels of substance P (SP) in patients with postoperative stiffness after arthroscopic rotator cuff repair. DESIGN: Plasma samples were obtained at 15 months from surgery from two groups of patients who underwent arthroscopic repair of a rotator cuff tear. In group 1, 30 subjects (14 men, 16 women; mean age 64.6 years, range 47 to 78) with shoulder stiffness 15 months after arthroscopic rotator cuff repair were recruited. In group 2, 30 patients (11 men, 19 women; mean age 57.8 years, range 45 to 77) were evaluated 15 months after successful arthroscopic rotator cuff repair. Immunoassays were performed with commercially available assay kits to measure the plasma levels of SP. RESULTS: Plasma levels of SP in patients with postoperative stiffness were significantly greater than those in the control group (mean 81.06 (SD 27.76) versus 23.49 (5.64), p<0.05). CONCLUSIONS: The plasma concentrations of substance P in patients with shoulder stiffness after arthroscopic rotator cuff repair are higher compared with plasma levels of SP in patients with a good postoperative outcome. The neuronal upregulation of SP shown in the plasma of patients with postoperative shoulder stiffness may underlie not only the symptoms but also its development of adhesive capsulitis.

[The numerous properties of the anticoagulant protein C]. / La proteina C anticoagulante ed i suoi molteplici ruoli.

The systemic inflammation associated to the simultaneous activation of blood coagulation and the alterated blood fibrinolysis, leads to microvascular endothelial injury, acute organ dysfunction and possibly death. Activated Protein C, a natural, multifunctional protein, has demonstrated antithrombotic, anti-inflammatory, and profibrinolitic properties and may be an important modulator of the vicious cycle whereby inflammation initiates coagulation and coagulation amplifies inflammation. Protein C couples with its receptor, EPCR (endothelial-cell protein-C receptor), and the ligand-receptor complex then interact with thrombin-thrombomodulin on endothelial surface to produce activated protein C (APC). Once activated, protein C then interact with its cofactor, protein S, to catalyze the inactivation of factors Va and VIIILa, two important accelerators of the clotting cascade, reducing thrombin generation and microvascular thrombosis. In addiction to its anticoagulant activity APC promotes profibrinolytic activity through the inhibition of plasminogen activator inhibitor-1, which is upregulated during inflammation. Inhibition of thrombin generation by APC decreases inflammation by inhibiting platelet activation, neutrophil recruitment, and mast-cell degranulation. APC also shows direct antiinflammatory properties, including blocking of cytokines production by monocytes and blocking cell adhesion. Moreover, APC has antiapoptotic properties that may contribute to its efficacy. In conclusion, APC, besides its physiologic role in the coagulation cascade, plays a key role in the pathophysiology of systemic inflammation justifying its potential therapeutic role in sepsis and systemic inflammatory responses.

Molecular characterisation and clonal analysis of group A streptococci causing pharyngitis among paediatric patients in Palermo, Italy.

Group A streptococci (n = 123), isolated consecutively from paediatric patients with pharyngitis from Palermo, Italy, were analysed. The emm and sof genes were sequenced, the presence of the speA and speC genes was investigated, and the macrolide resistance phenotypes and genotypes were determined. A limited number of emm/sof genotypes was found, and the most prevalent types were different from those found in a previous study from Rome. Macrolide resistance was found in the most prevalent clones, suggesting that the spread of mobile antibiotic resistance genes among the fittest clones in the community was the main mechanism influencing macrolide resistance rates in different emm types.

Procalcitonin as diagnostic marker of infection in solid tumors patients with fever.

In oncologic patients fever is a non-specific clinical marker of different clinical settings. Procalcitonin (PCT) seems to be the most promising infection marker. We aimed to define the potential role of PCT as an earlier diagnostic marker in patients with fever and solid tumor. This retrospective study enrolled 431 patients. All of them performed hemoculture (HE) and basal PCT assessment (reference laboratory cut-off: ≤0.5 or >0.5 ng/dL) before starting antibiotic therapy. Gram positive (G+), negative (G-) or Fungi infection were detected. A statistically significant difference in PCT levels between patients with positive and negative HE was observed (P < 0.0001). Moreover comparing PCT values in patients with positive and negative HE, we obtain in the positive HE subpopulation an AUC of 0.7 and a cut-off of 1.52 ng/dL reached high sensitivity (61.6%) and specificity (70.1%). Using this last cut-off, instead of the normal reference value, we achieve a risk reduction to overestimate an infection status of 23.4%. We support the clinic usefulness of serum PCT dosage in febrile advanced solid tumor patients. A PCT cut-off of 1.52 ng/dL could be helpful in the management of the antibiotic therapy preventing delays of oncologic treatments.

Clonality among Enterococcus faecium clinical isolates.

In the course of a survey to determine the epidemiology of enterococcal infections in Italy, a sudden increment, in a 1-year time, was noted in the number of glycopeptide resistant Enterococcus faecium isolated from different wards of the University Hospital in Rome, Italy. The isolates were characterized for clonal relatedness by comparing SmaI gel electropherotypes, presence of vancomycin-resistance genes, and expression of virulence factors. PFGE identified in a single pulsed type all the glycopeptide-resistant isolates but one. Resistance to high levels of aminoglycosides was expressed by these same isolates, which also included a majority of non biofilm-forming strains. Two esp gene-carrying strains were also identified in different PFGE types. Data indicates that a specific clone acquired, in the clinical setting, the genetic determinant for glycopeptide resistance, thus improving environmental adaptation and favoring its persistence and spread.

Colorectal carcinomas and PTEN/MMAC1 gene mutations.

PURPOSE: PTEN/MMAC1/TEP1 is a tumor suppressor gene encoding a dual-specificity protein phosphatase with homology to the cytoskeleton proteins, chicken tensin and bovine auxilin. PTEN mutations have been described in several types of human cancer. Recently, mutations at an (A)(6) repeat of PTEN exons 7 and 8 in colorectal cancer (CRC) patients with microsatellite instability have been detected. Moreover, an involvement of the transforming growth factor (TGF)-beta pathway in hereditary colorectal syndromes has been proposed. EXPERIMENTAL DESIGN: In this study, we analyzed the frequency of PTEN gene mutations in 36 CRC patients and 5 colon cancer cell lines. Furthermore, in 16 of 36 patients, microsatellite instability and TGF-beta receptor II analysis was possible. The study was performed by PCR and automated sequencing of the entire coding region of the PTEN gene. RESULTS: About 17% of colon cancer patients and one of five (HSR 320) colon cancer cell lines had mutations. Mutations were detected only among patients with locally advanced or metastatic CRC. PTEN mutations were detected in three of five (60%) patients showing both microsatellite instability and TGF-beta receptor II mutations. These patients presented with advanced or metastatic CRC CONCLUSIONS: Overall, these results show that PTEN alteration together with TGF-beta pathway inactivation could contribute to tumorigenesis and metastatic spread of sporadic and microsatellite unstable CRC.

Antimicrobial susceptibility, biochemical and genetic profiles of Staphylococcus haemolyticus strains isolated from the bloodstream of patients hospitalized in critical care units.

Staphylococcus haemolyticus strains (n=20), responsible of blood stream infections, were consecutively isolated from patients hospitalized in two different wards at high risk of infection. Strains displayed high rate of resistance to oxacillin (90%). All strains but two with decreased susceptibility (MIC = 4 microg/mL), were sensitive to vancomycin. Ten strains were resistant to teicoplanin. Among the strains susceptible to glycopeptides, three displayed heteroresistance to vancomycin and seven to teicoplanin, when tested by Etest technique with 2 x McFarland inoculum. Biochemical reactions allowed to assign strains to eight biotypes, with 11 strains clustering under two main biotype A and biotype B. Pulsed-field-gel-electrophoresis (PFGE) identified 11 different PFGE-types. Seven strains grouping under the major PFGE-type 1 and three strains clustering in PFGE-type 2, closely correlated to biotype A and biotype B respectively. Seven teicoplanin-resistant isolates clustered in the PFGE-type 1, two in the PFGE-type 2 and one in PFGE-type 5. Therefore, teicoplanin-resistant strains were biochemically and genetically related and clonally distributed, despite different clones of S. haemolyticus circulated in the units during the study period.

Antibiotic resistance and genotypic characterization by PFGE of clinical and environmental isolates of enterococci.

Fifty-four Enterococcus faecalis and 20 Enterococcus faecium isolates from clinical and non-human sources in Rome, Italy, were characterized by antibiotic resistance and pulsed field gel electrophoresis (PFGE). Resistance to vancomycin, teicoplanin, ampicillin, and ciprofloxacin was more frequent in E. faecium than in E. faecalis, whereas high-level resistance to aminoglycoside was found primarily in E. faecalis. Multi-resistance was found primarily among clinical isolates, but was also observed among environmental isolates. Common genotypes shared among clinical and environmental isolates were observed, however, the majority of isolates occurred as unique, source-specific clones. Several PFGE types were associated with shared features in their antibiotic resistance patterns; evidences of clonal spread between and within wards were also noted. This is the first report indicating clonal relatedness between human and environmental enterococci isolated in Italy.

Oxaliplatin may induce cytokine-release syndrome in colorectal cancer patients.

INTRODUCTION: Oxaliplatin, a third-generation platinum analogue, is a novel compound with proven anti-tumor activity in colorectal cancer. Moreover, oxaliplatin appears to be relatively well tolerated and easy to handle, even on an outpatient basis. PATIENTS AND METHODS: Five advanced colorectal cancer patients treated with oxaliplatin-based chemotherapy developed, after the end of oxaliplatin infusion, similar idiosyncratic reactions characterized by chills, high fever, hypotension, abdominal pain, nausea and often diarrhoea. Venous blood for IL-6 and TNF-alpha assessment was drawn just after the beginning of the reaction and 15 and 30 minutes later. After drawing the third venous sample, intravenous dexamethasone (8 mg) was administered and the drawing of other two venous samples was performed (180 and 360 minutes after the beginning of the reaction). RESULTS: TNF-alpha and IL-6 serum concentrations significantly decreased after steroid therapy administration. The decrease of TNF-alpha and IL-6 levels went along with the clinical complete regression of symptoms and signs in all the 5 patients. No statistically significant correlation was found between other laboratory parameters and basal cytokine levels or cytokine decrease after steroid therapy. DISCUSSION: Our results clearly show that that idiosyncratic reaction observed in colorectal cancer patients after oxaliplatin infusion may be due to a massive release of cytokines such as TNF-alpha and IL-6. Symptom regression following steroid therapy administration went along with significant decrease of cytokines levels, confirming that TNF-alpha and IL-6 play a role in the pathogenesis of this reaction.

[Transplantation of the intestines and bacterial translocation]. / Trapianto di intestino e traslocazione batterica.

Infections, sepsis and multiple organ failure syndrome are associated with high morbidity and mortality in human and experimental small bowel transplantation (SBTx). These complications are attributed to bacterial translocation demonstrated in animal and human studies. Bacterial translocation (BT) is defined as the passage of viable bacteria from the intestinal lumen to other tissues or organs. BT has been associated with different clinical and experimental situations, hemorrhagic shock, trauma, bowel obstruction, immunodepression, total parenteral nutrition, antibiotics. Although BT has been investigated in several small and large animal models of SBTx, precise information on the mechanisms involved are not available. It is possible that the operative procedure by itself may promote BT for the interaction of a number of factors such as preservation, ischemia/reperfusion, abnormal motility, lymphatic disruption and aberrant systemic venous drainage, acute or chronic rejection and antibiotic therapy. Furthermore, the potent immunosuppressive therapy used in these patients may augment the deleterious effects caused by BT. In this review we examined the existing literature concerning BT with particular regard to intestinal transplantation, to better understand the alterations in the symbiotic relationship between immunocompromised host and his gut microflora after SBTx.

[Bacterial translocation and its surgical implications]. / Traslocazione batterica e sua rilevanza chirurgica.

The passage of viable bacteria through epithelial mucosa into lamina propria and then to mesentheric lymphnodes, and possibly other tissues was defined bacterial translocation (BT) by Berg and Garlington. The transepithelial passage of bacteria out of the intestinal lumen seems to occur in a variety of surgical conditions, and it is suspected to be involved in systemic inflammatory response syndrome, sepsis and multiorgan failure. There is increasing evidence that many nosocomial infections are caused by enteric translocating microorganisms, although the exact incidence of BT in humans is difficult to establish. Consensus is emerging that the barrier function of the gut is relevant in established critical illness and in patients at risk of developing sepsis and clinical studies have provided strong evidence that systemic infections often originate from intestinal flora in high risk patients. So the suspect of BT is made when there is infection after trauma, burns, major surgery, chemotherapy and immuno suppression. Bacterial translocation is also associated with organ transplantation, especially with small bowel transplantation. The Authors have summarized published experimental and clinical studies that have tried to understand the occurrence, mechanisms and effects of this complex process. At the present time there is a near full understanding of the relevance of BT like an interplay of diverse factors in a physiologically, immunologically and microbiologically complex intestinal tract. However additional experimental and clinical studies are needed to clarify the relationship between these phenomena and the development of sepsis or multiple organ dysfunction syndrome.

Invasive neonatal GBS infections from an area-based surveillance study in Italy.

During an area-based study, 75 group B streptococcus (GBS) strains isolated both from early-onset disease (EOD, 37 strains) and from late-onset disease (LOD, 38 strains) were analysed for serotype, pulsed field gel electrophoresis (PFGE) and multilocus sequence typing profiles, protein markers and antibiotic resistance. Serotype III, possessing the rib gene, was the most frequent (54 strains, 72%) and responsible for 89.5% and 54% of LOD and EOD, respectively. Forty-six serotype III strains belonged to the same PFGE type and clonal complex 17, already described as an over-represented clone in neonatal invasive GBS infections. Other serotypes were Ia (9.3%), II (6.7%), Ib (5.3%), V (5.3%) and IV (1.3%). Seventeen PFGE groups were identified comprising strains with related sequence types; conversely, strains displaying the same sequence type could belong to different PFGE groups. When both neonate and maternal strains from vaginorectal swabs and/or milk were available (eight cases), they were indistinguishable. Resistance to erythromycin (12%) was associated with a constitutive resistance to clindamycin in five cases (four carrying the erm(B) gene and one both the erm(B) and mef(E) genes) and with an inducible clindamycin resistance in two cases (one possessing the erm(A) gene, the other the erm(T) gene). Two isolates displayed the M phenotype (mef(E) gene). All strains but five were resistant to tetracycline, mostly mediated by the tet(M) gene (97.1%). The study underlined the importance of an active surveillance system for the elucidation of a GBS population structure causing neonatal infections and allowed the detection of rare antibiotic resistance determinants [erm(T)].