Alex Smithson

Quinolone-Resistant Uropathogenic Escherichia coli Strains from Phylogenetic Group B2 Have Fewer Virulence Factors than Their Susceptible Counterparts

ABSTRACT The prevalence of 31 virulence factors was analyzed among nalidixic acid-susceptible and -resistant Escherichia coli strains from phylogenetic group B2. Hemolysin, cytotoxic necrotizing factor 1, and S and F1C fimbriae genes were less prevalent among nalidixic acid-resistant E. coli strains. Quinolone resistance may be associated with a decrease in the presence of some virulence factors.

Expression of Interleukin-8 Receptors (CXCR1 and CXCR2) in Premenopausal Women with Recurrent Urinary Tract Infections

ABSTRACT The migration of neutrophils through infected tissues is mediated by the CXC chemokines and its receptors (CXCR1 and CXCR2). It has been proposed that a CXCR1 deficiency could confer susceptibility to acute pyelonephritis in children. The objective of the study is to assess the surface expression of CXCR1 and CXCR2 and the existence of polymorphisms in the CXCR1 gene in premenopausal women with recurrent urinary tract infections. The study included 20 premenopausal women with recurrent urinary infections, with normal urinary tracts, and without diseases potentially associated with relapsing urinary infections and 30 controls without previous urinary infections. The levels of CXCR1 and CXCR2 expression on neutrophils were measured and analyzed by flow cytometry by measuring the mean fluorescence intensity (MFI) channel. The promoter and coding regions of the CXCR1 gene were analyzed for the presence of polymorphisms by a sequence-based typing method. Patients with recurrent urinary tract infections exhibited median levels of CXCR1 expression, determined from MFI values, similar to those of the controls. The analysis of CXCR2 showed that patients with recurrent urinary infections had lower median levels of expression, determined from the MFI values, than the controls (P = 0.002, Mann-Whitney U test). No polymorphisms were detected at the promoter or at the exon 1 region of the CXCR1 gene either in the patients or in the controls. Polymorphisms were detected at the exon 2 of CXCR1, but their frequencies did not differ between patients and controls. We have found a low level of CXCR2 expression in patients with recurrent urinary tract infections. These results suggest that a low level of CXCR2 expression may increase the susceptibilities of premenopausal women to urinary tract infections.

Diagnostic and management of spontaneous rectus sheath hematoma

BACKGROUND Spontaneous rectus sheath hematoma is an uncommon and often misdiagnosed cause of abdominal pain. The aim of this study is to describe our experience in their management. METHODS Retrospective analysis of the characteristics and outcomes of the spontaneous rectus sheath hematomas diagnosed over the last 12years was conducted. RESULTS 24 patients were included (66% women; mean age: 74years; range: 54-87). All cases presented predisposing factors mainly anticoagulant therapy in 21 (87.5%) patients, hypertension in 19 (79.1%) and abdominal surgery in 12 (50%) cases. Eighteen (75%) referred triggering factors like coughing being the most common one, present in 17 (70.8%) patients. The main clinical findings were abdominal pain in 21 (87.5%) cases and the existence of an abdominal mass in 20 (83.3%). The diagnosis was confirmed by abdominal ultrasonography and/or computerized tomography in 23 (95.8%) patients. Nineteen cases (79.1%) responded to conservative management while 5 (20.8%) required interventional treatment, which consisted in an arteriography with selective embolization of the epigastric arteries in all cases. Four (80%) of the patients needing interventional treatment were receiving low molecular weight heparin. Nine (37.5%) patients developed hypovolemic shock and 1 (4%) died. CONCLUSIONS Spontaneous rectus sheath hematomas should be considered in the differential diagnosis of abdominal pain, particularly in elderly women under anticoagulant therapy with onset of symptoms after a bout of cough. Most cases respond to conservative management, although those related to low molecular weight heparin might require interventional treatment; arteriography with selective embolization of the epigastric arteries is the first therapeutic option.

Evaluation of inflammatory and renal-injury markers in women treated with antibiotics for acute pyelonephritis caused by Escherichia coli.

ABSTRACT The evolution and the relationship between inflammatory and renal-injury markers in women with acute uncomplicated pyelonephritis under antimicrobial therapy were investigated in a prospective study. Markers were measured before and 6 and 24 h after the intravenous administration of 1 g of ceftriaxone. Before treatment, the median levels of all markers except the serum creatinine levels were high. Twenty-four hours after the onset of antibiotic treatment, the C-reactive protein (CRP) level continued to be high, while the serum interleukin-6 (IL-6) levels and the urine IL-6, IL-8, albumin, and immunoglobulin G (IgG) levels decreased significantly. In contrast, serum creatinine and tumor necrosis factor alpha levels and urine N-acetyl-β-glucosaminidase, α1-microglobulin, and β2-microglobulin levels did not change over time. There was a significant correlation between IL-6 and IL-8 levels and urine albumin and IgG levels (urine albumin and IgG levels are glomerular and urinary tract-injury markers) as well as between serum CRP levels and the levels of the tubular-injury markers. In women with acute pyelonephritis, appropriate antibiotic treatment rapidly decreases serum IL-6 levels and urine IL-6 and IL-8 levels, which correlate well with urine albumin and IgG levels.

Association between mannose-binding lectin deficiency and septic shock following acute pyelonephritis due to Escherichia coli.

ABSTRACT Structural and promoter MBL2 gene polymorphisms responsible for low MBL levels are associated with increased risk of infection. The objective of this study was to assess the possible association between polymorphisms of the MBL2 gene and the incidence of septic shock and bacteremia in patients with acute pyelonephritis due to Escherichia coli. The study included 62 female patients with acute pyelonephritis due to E. coli who required hospital admission, as well as 133 healthy control subjects. Six single-nucleotide polymorphisms (−550 G/C, −221 C/G, +4 C/T, codon 52 CGT/TGT, codon 54 GGC/GAC, and codon 57 GGA/GAA) in the MBL2 gene were genotyped by using a sequence-based typing technique. No significant differences were observed in the frequencies for low-expression MBL2 genotypes (O/O and LXA/O) between patients with acute pyelonephritis and healthy controls. Patients with acute pyelonephritis and septic shock had a higher incidence of low-expression MBL2 genotypes than patients with acute pyelonephritis without septic shock (odds ratio = 9.019, 95% confidence interval = 1.23 to 65.93; P = 0.03). No association was found between bacteremic acute pyelonephritis and low-expression MBL2 genotypes. We found that low-expression MBL2 genotypes predispose to septic shock but not to bacteremia in patients with E. coli-induced acute pyelonephritis. Determination of MBL2 polymorphisms could be useful for assessing the risk of septic shock in women undergoing acute pyelonephritis.

Polymorphic Receptors of the Innate Immune System (MBL/MASP-2 and TLR2/4) and Susceptibility to Pneumococcal Bacteremia in HIV-Infected Patients: A Case-Control Study

UNLABELLED Some deficient genetic polymorphisms of the innate immune system have been correlated to a higher susceptibility to different infections, especially in immunocompromised patients. The possible association between an increased incidence of pneumococcal bacteremia in HIV-infected patients, and deficient polymorphisms of the mannose-binding lectin (MBL), MBL-associated serine protease 2 (MASP-2), and toll-like receptors (TLR) 2 and 4 is analyzed by means of a case-control study. CASES HIV-infected patients with pneumococcal bacteremia. CONTROLS HIV-infected patients without previous pneumococcal bacteremia matched with cases by sex and CD4 count in a 2:1 ratio. Fifty-seven cases and 114 controls were studied. Demographics, HIV infection status, antiretroviral therapy, risk factors for pneumococcal disease, and genotypes of MBL2, MASP2, TLR2 and TLR4 were analyzed. The prevalence of the MBL2, MASP2, TLR2 and TLR4 gene polymorphisms was similar in both groups. No statistical significance was found (OR 0.77, IC 95% 0.27 - 2.13) when analyzing the possible association of MBL2 deficient polymorphisms with pneumococcal bacteremia. In HIV infected patients, no association between the presence of deficient polymorphisms of MBL2, MASP2, TLR2 and TLR4 and the incidence of pneumococcal bacteremia was found.

Is eosinopenia a reliable marker of sepsis

We have read with interest the article by Abidi and colleagues [1] in which the authors point out that eosinopenia could be useful to differentiate between noninfection and infection in patients recently admitted to an intensive care unit (ICU). The association of eosinopenia with infections is not new and has been described previously [2]. To test this hypothesis, we reviewed 191 patients (age >18 years, with a minimum ICU stay of 24 hours) admitted to the medical ICU of our hospital. We exuded HIV-infected patients and those with hematological malignancies. Total leukocyte and eosinophil count (EC) were measured at ICU admission. The results are shown in Table ​Table1.1. Although the EC was lower and the proportion of patients with eosinopenia (<40 cells/ml) was higher in the noninfectious systemic inflammatory response syndrome (SIRS) group compared with the infectious SIRS group, these differences were not statistically significant. Therefore, the EC was not useful to distinguish between infection and noninfection. Although one limitation of our study was the absence of a non-SIRS group, the EC of our noninfectious SIRS group was similar to the EC found in the non-SIRS group in the study by Abidi and colleagues [1]. Another study failed to observe an association between eosinopenia and bacteremia [3]. Table 1 Baseline characteristics of the ICU patients included in the study In conclusion, eosinopenia was not a reliable marker of infection. Other analytical parameters, such as C-reactive protein, have demonstrated to be helpful not only for the diagnosis of infection but also as a marker of severity of organ dysfunction in sepsis [4].

Genotypes Coding for Low Serum Levels of Mannose-Binding Lectin Are Underrepresented among Individuals Suffering from Noninfectious Systemic Inflammatory Response Syndrome

ABSTRACT Gene polymorphisms, giving rise to low serum levels of mannose-binding lectin (MBL) or MBL-associated protease 2 (MASP2), have been associated with an increased risk of infections. The objective of this study was to assess the outcome of intensive care unit (ICU) patients with systemic inflammatory response syndrome (SIRS) regarding the existence of functionally relevant MBL2 and MASP2 gene polymorphisms. The study included 243 ICU patients with SIRS admitted to our hospital, as well as 104 healthy control subjects. MBL2 and MASP2 single nucleotide polymorphisms were genotyped using a sequence-based typing technique. No differences were observed regarding the frequencies of low-MBL genotypes (O/O and XA/O) and MASP2 polymorphisms between patients with SIRS and healthy controls. Interestingly, ICU patients with a noninfectious SIRS had a lower frequency for low-MBL genotypes and a higher frequency for high-MBL genotypes (A/A and A/XA) than either ICU patients with an infectious SIRS or healthy controls. The existence of low- or /high-MBL genotypes or a MASP2 polymorphism had no impact on the mortality rates of the included patients. The presence of high-MBL-producing genotypes in patients with a noninfectious insult is a risk factor for SIRS and ICU admission.

Acute pyelonephritis in adults: an update

Recent advances in pathogenesis, changes in antimicrobial susceptibility of uropathogens and new therapeutic guidelines have resulted in a growing interest in acute pyelonephritis. New virulence factors of uropathogens have been described as well as a possible link between antibiotic resistance and

Blood Cultures for Men with Febrile Urinary Tract Infection

We have read with interest the article by Etienne et al. in which the authors evaluate the value of blood cultures (BC) in patients with acute prostatitis (AP) ([2][1]). Since our group has a particular interest in these patients, which are included in a database, we would like to make some comments