A. Speciale

Serum levels of the interferon-γ-inducing cytokine interleukin-18 are increased in individuals at high risk of developing Type I diabetes

Aims/hypothesis. Interleukin (IL)-18 is a cytokine primarily produced by macrophages and capable of inducing T lymphocyte synthesis of interferon (IFN)-γ. An up-regulated synthesis of IFN-γ with consequential Type I cytokine dominance has been repeatedly shown in Type I (insulin-dependent) diabetes mellitus and thought to be involved in its pathogenesis. Because increased production of IFN-γ could be secondary to a dysregulated synthesis of IL-18, we compared the circulating levels of IL-18 in patients with newly diagnosed Type I diabetes with those of non-diabetic first-degree relatives and healthy control subjects. Methods. Serum samples were obtained from healthy control subjects, patients with newly diagnosed Type I diabetes, and their healthy first-degree relatives. The latter were subdivided into “low” and “high” risk prediabetics depending on whether they were negative or positive for two or more of the anti-pancreatic autoantibodies ICA, GAD, IA-2 and IAA. Serum levels of IL-18 were measured by solid-phase ELISA. Results. Interleukin (IL)-18 was above the detection limit of 25 pg/ml in 7 of 40 (17 %) healthy control subjects, in 5 of 35 (14 %) patients and in 3 of 30 (10 %) first-degree relatives at low risk of developing Type I diabetes. In contrast, IL-18 could be detected in 19 of 28 (68 %; p < 0.0001) relatives at high risk. The mean serum level of IL-18 was higher in these individuals when compared with the low-risk relatives, patients and control subjects. Conclusion/interpretation. IL-18 serum levels are increased selectively during the early, subclinical stage of Type I diabetes. [Diabetologia (2001) 44: 309–311]

Acute otitis media: From diagnosis to prevention. Summary of the Italian guideline

Acute otitis media (AOM) is the most common disease occurring in infants and children and has major medical, social and economic effects. If we consider the Italian pediatric population and the incidence rates in different age ranges it can be calculated that almost one million cases of AOM are diagnosed in Italy every year. Various attempts have been made internationally to clarify the most appropriate ways in which AOM should be managed. In Italy, this has been done at local or regional level but there have so far been no national initiatives. The objective of this guideline is to provide recommendations to pediatricians, general practitioners and otolaryngologists involved in the clinical management of acute otitis media in healthy children aged 2 months to 12 years. After a systematic review and grading of evidences from the literature, the document was drafted by a multidisciplinary panel with identified key clinical questions related to diagnosis, treatment of the acute episode, management of complications and prevention.

Minimal inhibitory concentrations and time-kill determination of moxifloxacin against aerobic and anaerobic isolates.

Moxifloxacin is a new oral 8-methoxy-quinolone with a wide spectrum of activity against Gram-negative and anaerobic bacteria, atypical micro-organisms and multi-resistant Gram-positive bacteria. This study was designed to assess the in vitro activity of moxifloxacin against Gram-positive bacteria with different resistance patterns, anaerobes and atypical micro-organisms such as Chlamydia and Mycoplasma. Moxifloxacin had good activity against Streptococcus pneumoniae with all strains inhibited by < or =0.12 mg/l. The minimal inhibitory concentrations (MICs) of moxifloxacin for Streptococcus pyogenes and Streptococcus agalactiae ranged from 0.03 to 0.5 mg/l while those of ciprofloxacin were about two- to four-fold higher (MICs=0.12-1 mg/l). Moxifloxacin was poorly active against enterococci but its activity against Clostridium and Bacteroides spp. was in the same range as that of metronidazole and superior to that of clindamycin. Moxifloxacin was substantially more active than both ciprofloxacin and sparfloxacin against Chlamydia.

Antibacterial activity of moxifloxacin against periodontal anaerobic pathogens involved in systemic infections

The in vitro activity of moxifloxacin was compared with that of penicillin G, amoxycillin/clavulanate, cefoxitin, erythromycin, clindamycin and metronidazole against 158 isolates associated with periodontal infections. MIC(50)/MIC(90) values of moxifloxacin were respectively 0.06/0.5 mg/l for Porphyromonas gingivalis (35), for Prevotella spp. (28) and Actinomyces spp. (35), 0.12/0.25 mg/l for Fusobacterium nucleatum (20) and 0.06/0.12 mg/l for Peptostreptococcus spp. (30). The minimum inhibitory concentration (MIC) range of moxifloxacin for Bacteroides forsythus (6) and Campylobacter rectus (4) was 0.06-0.12 mg/l. The minimum bactericidal concentrations were equal to or 2-4 times the MIC values. Moxifloxacin produced a bactericidal effect at 8 h. Our results show that moxifloxacin has good antibacterial activity against periodontal pathogens comparable with that of cefoxitin and amoxycillin/clavulanate, and better than that of clindamycin, metronidazole and penicillin.

Bacteriological findings and antimicrobial resistance in odontogenic and non-odontogenic chronic maxillary sinusitis.

The main objectives of this study were to estimate the frequency of chronic maxillary sinusitis of dental origin, and to evaluate the microbiology of odontogenic and non-odontogenic chronic maxillary sinusitis. Aspirates from 59 patients with chronic maxillary sinusitis (47 non-odontogenic, 12 odontogenic), collected during a 3-year period, were microbiologically processed for aerobic and anaerobic bacteria. Moreover, antimicrobial susceptibility was evaluated in the isolated bacteria. In this study, 20 % of chronic maxillary sinusitis cases were associated with a dental origin, and sinus lift procedures were the main aetiological factor. Our microbiological findings showed that all specimens from chronic maxillary sinusitis were polymicrobial. Sixty aerobes and 75 anaerobes were recovered from the 47 cases of non-odontogenic sinusitis (2.9 bacteria per specimen); 15 aerobes and 25 anaerobes were isolated from the 12 patients with odontogenic sinusitis (3.3 bacteria per specimen). The predominant aerobes were Staphylococcus aureus (27) and Streptococcus pneumoniae (16), while the more frequent anaerobes were Peptostreptococcus species (31) and Prevotella species (30). Haemophilus influenzae and Moraxella catarrhalis were absent in sinusitis associated with a dental origin. Overall, 22 % of Staphylococcus aureus isolates were oxacillin-resistant, and 75 % of Streptococcus pneumoniae isolates were penicillin-resistant and/or erythromycin-resistant; 21 % of anaerobic Gram-positive bacteria were penicillin-resistant, and 44 % of anaerobic Gram-negative bacteria were β-lactamase-positive. Vancomycin and quinopristin-dalfopristin had the highest in vitro activity against Staphylococcus aureus and Streptococcus species, respectively; amoxicillin-clavulanate and cefotaxime showed the highest in vitro activity against aerobic Gram-negative bacteria; and moxifloxacin, metronidazole and clindamycin were the most active against anaerobic bacteria.

Effect of a broad-spectrum cephalosporin on the oral and intestinal microflora in patients undergoing colorectal surgery.

The influence of ceftriaxone on oral and intestinal flora was investigated in 10 patients undergoing colorectal surgery. Ceftriaxone was given intravenously in one 2g dose before anesthesia. Saliva and feces samples were collected and analyzed on day 0, 3, 5, 14 and 28 after drug administration. All specimens were cultured quantitatively for aerobic and anaerobic microorganisms; representative colonies of each morphologic type of organism cultured were identified. The oral aerobic flora was somewhat affected by the administration of ceftriaxone. In all patients the number of Streptococci, Staphylococci and Neisseria decreased during the 5 days after ceftriaxone administration. No significant changes in the number of anaerobic commensal occurred. The oral microflora of all patients after 14 days had returned to normal. The aerobic fecal flora was considerably affected: in all patients enterobacteria were eliminated or strongly suppressed. Only minor changes in the number of aerobic gram-positive bacteria were observed, and the anaerobic intestinal flora showed only minor alterations. On day 28 the intestinal flora were normalized in all respects. No new colonizing microorganisms were isolated during the investigation period and no colonization with ceftriaxone-resistant bacteria was observed. No postoperative infection occurred and no adverse effects were registered.

Antimicrobial Susceptibility and β-Lactamase Production of Anaerobic and Aerobic Bacteria Isolated from Pus Specimens from Orofacial Infections

Abstract Most suppurative orofacial infections are polymicrobial. Information regarding the antimicrobial susceptibility of the microorganisms involved can be useful in the choice of an effective antibiotic therapy. In this study we determined the antimicrobial susceptibility of a total 235 anaerobic and aerobic bacteria recently isolated from pus specimens of orofacial infections. All the viridans streptococci were susceptible to penicillin, cefotaxime, cefoxitin, imipenem and levofloxacin. Imipenem and levofloxacin were active against 100% of the anaerobic Gram-positive organisms isolated. Among the anaerobic Gram-negative rods β-lactamase production was detected in all species except Campylobacter rectus. Amoxicillin-clavulanate, cefoxitin, imipenem and metronidazole were active against all the isolates of anaerobic Gram-negative species. Isolates resistant to erythromycin were found in all the species tested, however, resistance to clindamycin was only detected in Porphyromonas gingivalis and Bacteroides ureolyticus. Isolates resistant to levofloxacin were detected in P. gingivalis and Prevotella sp.

Antibacterial activity of Propolis and its active principles alone and in combination with macrolides, beta-lactams and fluoroquinolones against microorganisms responsible for respiratory infections

Abstract Propolis is produced by bees and is reported to have several pharmaceutical properties. Its antibacterial activity against strains causing upper respiratory tract infections is particularly important: Propolis might be used as a therapeutic agent to prevent the bacterial infections that sometimes overlap viral infections. In this study the in vitro activity of both an alcoholic solution and a hydroglyceric extract of Propolis as well as its active principles, was tested against bacteria responsible for respiratory infections (Streptococcus pneumoniae, Haemophilus influenzae, Haemophilus parainfluenzae, Moraxella catarrhalis and Streptococcus pyogenes). We also evaluated the in vitro activity of a combination of propolis and its active principles and some beta-lactams, macrolides and fluoroquinolones. Our results, though not demonstrating a clearly synergistic activity between antibiotics and Propolis and its constituents, show the possibility of using natural preparations, due to their antimicrobial and anti-inflammatory properties, to enhance antibacterial therapy.

The Italian Epidemiological Survey 1997 /1999 Antimicrobial susceptibility data of Haemophilus influenzae, Haemophilus parainfluenzae and Moraxella catarrhalis in Italy

The Italian Epidemiological Survey began a surveillance study with the aim of monitoring the antimicrobial resistance of respiratory pathogens. From 1997 to 1999, 2028 strains of Haemophilus influenzae and 523 strains of Haemophilus parainfluenzae were collected from 59 Clinical Microbiology Laboratories distributed throughout Italy. In 1998, the study was extended to include Moraxella catarrhalis and a total of 360 isolates were collected. There was a significant increase in the beta-lactamase production both for H. influenzae (from 5% in 1997 to 16% in 1999) and for H. parainfluenzae (from 5% in 1997 to 22% in 1999). Beta-lactamase production in M. catarrhalis was 84% in 1998 and 87% in 1999. Beta-lactamase production affected the susceptibility to unprotected penicillins (87% in H. influenzae, 85% in H. parainfluenzae and 34% in M. catarrhalis), and in part the susceptibility to cefaclor (about 98%). Amoxycillin/clavulanate, cefixime, ceftriaxone and ciprofloxacin were active against all strains of H. influenzae, H. parainfluenzae and M. catarrhalis.

Antimicrobial activity of Rhus coriaria L. leaf extract

The antibacterial activity of Rhus coriaria leaf methanol extract was assayed against Gram‐positive and Gram‐negative bacteria; antimycotic activity was assayed against some Candida species. MICs were determined by a broth microdilution assay in microlitre plates using Mueller–Hinton medium. MBCs were determined by plating 0.01 mL samples from clear 1 mL tubes onto agar plates.