Volume 8, Issue 2, 2000
Review
Cefuroxime stability to beta-lactamases: clinical implications
Amicosante Gianfranco,
Marchetti Federico
Bacteria continuously evolve their resistance mechanisms to antibiotics, either in community or in the hospital setting. Production of beta-lactamases is one of the oldest way to overcome antimicrobial agents activity, since it was first described in 1944 immediately after the penicillin discovery. Beta-lactamases are enzymes hydrolysing the beta-lactam nucleus of beta-lactam antibiotics by using two strategies: a nucleophilic attack of a serine residue or activating a water molecule via a Zn++. Cefuroxime is a injectable cephalosporin which can be also orally administered as a pro-drug named cefuroxime axetil. Cefuroxime has been classified as a second generation cephalosporin, even though the strict subgrouping of cephalosporins into classes is critically discussed by the Authors. Cefuroxime was the first beta-lactam with a higher stability to beta-lactamase hydrolysis due to its methoxy-imino side chain in position 7 of the cephem nucleus. Many of the clinically significant bacterial species producing beta-lactamases such as Haemophilus, Moraxella, Staphylococci and most Enterobacteriaceae then remain susceptible to cefuroxime. The more evoluted enzymes such as carbapenemases, extended-spectrum beta-lactamases or over-expressed cephalosporinases hydrolyse nearly all the beta-lactams antibiotics including cefuroxime. The available literature on the bacterial susceptibility to cefuroxime in Italy and use of cefuroxime in clinical settings where beta-lactamase producing bacteria could be involved has been analysed in the review. In conclusion, cefuroxime still represents a valid therapeutic option even in presence of most of the beta-lactamase producing bacteria.
Antibiotics and kidney
Nardiello Salvatore,
Catapano Fausta,
Galanti Bruno
Renal excretion is the most important route of elimination for the majority of antibiotics, and some antibiotics may cause renal injury by direct and/or immunologic mechanisms. These conditions determine a dose relationship between antibiotic therapy and renal function.
In this review we report some practical guidelines for the correct administration of antibiotics in patients with decreased renal function. Currently used antibiotics that are most frequently associated to nephrotoxicity are also examined, and for each of them the incidence and degree of renal damage, pathogenic mechanisms and preventive measures are reported.
This review emphasizes the need for a careful assessment of renal function in patients with acute and chronic infections undergoing antibiotic therapy.
Original article
Giardiasis: a parasitic disease of continued topicality. Study of prevalence among a selected adult population
Giacometti Andrea,
Cirioni Oscar,
Fortuna Moira,
Drenaggi Davide,
Veccia Salvatore,
Derrico Marcello Mario,
Scalise Giorgio
We studied the prevalence of Giardia intestinalis in five patients risk groups including institutionalised psychiatric of elderly subjects, HIV-positive immunocompromised patients, immigrants from developing countries and travellers to tropical countries. Stool specimens of 1319 subjects were studied. Stools were collected in triplicate from each subject. The presence of bacteria, viruses and parasites was evaluated. A direct smear examination from fresh faecal specimens and after concentration with formalin-ethylacetate was performed for parasite examination. Smears were also stained by a modified acid fast method and then examined for the presence of Cryptosporidium spp. and other coccidia. Cryptosporidium parvum and G. intestinalis were also detected by immunofluorescent assay. Contemporaneously a microbiological investigation was performed with standard culture, biochemical techniques and viral detection. Clinical data about each subject were provided by standardised questionnaires. G. intestinalis was detected in the stools of 41 subjects (3.5%). The immigrants (5.5%), the institutionalised psychiatric patients (5.0%) and HIV immunocompromised patients (4.6%) showed the highest prevalence. By contrast, travellers showed the lowest prevalence (2.5%). G. intestinalis was the pathogen most frequently detected. The cohorts with the presence of more risk factors showed the highest prevalence. The low prevalence of the parasite among travellers demonstrated the significance of health education before travelling and of the most important role of bacterial etiopathogenesis in “traveller’s diarrhoea”. Epidemiologically, G. intestinalis remains a protozoon of evident importance and is significantly present in Italy.
Anti-Pseudomonas aeruginosa antibodies and lung disease in cystic fibrosis
Pardo Francesca,
Iapichino Luciana,
Collura Mirella,
Furnari Maria Lucia,
Termini Lisa,
Cascio Antonio,
Giordano Salvatore
The aim of our study was to diagnose and to control three aspects of the evolution of lung disease in CF: the absence of infection, the intermittent colonization and chronic infection by Pseudomonas aeruginosa.
Therefore a study of anti-pseudomonas antibodies (Ab) (anti-protease, anti-elastin and antihexo-toxin A) for diagnosis and follow-up of CF patients was considered. Moreover, we related the presence of Ab to the sputum culture, to FEV1, to patient age and to genotype. Tbe Ab were dosed in 121 patients by quantitative ELISA method. Values < 1: 500 were considered negative, values> 1: 500 and < 1:1250 borderline, and > 1:1250 positive. 16.5% of patients did not have Ab, 17% had borderline values and 69.5% had positive values. All the patients with negative Ab had negative sputum culture; 47% of patients with borderline values had at least one positive culture while 53% were negative. 87% of patients with positive values had chronic colonization, 13% intermittent colonization.
The increase in the Ab rate is statistically related to a more severe lung disease (p < 0.013). The presence of a severe mutation (F 508) is related to positive values of Ab. Evaluation of anti-Pseudomonas aeruginosa is an important tool for diagnosis and follow-up of CF lung disease
Evolution of hepatitis C virus (HCV) infection acquired at birth
Minola Eliseo,
Berera Francesca,
Fracassetti Osvaldo,
Quinzan Giampaolo,
Lorenzi Natale,
Delvecchio Giacomo
Objectives Our aim was to analyze the evolution of HCV infection in children infected at birth.
Methods Between September 1994 and December 1998 we analyzed in a prospective study 8 children born of anti-HCV and HCV RNA positive women. Each baby was controlled at birth, every 3 months during the first year of life, and then every 6 months searching for anti-HCV antibodies (ELISA 3, RIBA 2-3), HCV RNA (RT PCR), ALT and viral genotype.
Results Viral RNA was detectable in the first 3 months of life in all babies (100%) and remained positive during the follow-up. Viral genotypes were the same for mothers and their children. In 6 babies (75%) ALT remained pathologic during follow-up.
Conclusions HCV infection in children usually has an asymptomatic outcome; the infection has chronic features in the majority of cases.
Epidemiology and sensitivity to antibiotics in paediatric respiratory infections over a 4-year period. Retrospective study of 460 H. influenzae, S. pneumoniae and M. catarrhalis strains
Manno Graziana,
Belli Maria Luisa,
Bassetti Matteo,
Ugolotti Elisabetta,
Fenu Maria Laura,
Piana Sandra,
Bassetti Dante
H. influenzae, S. pneumoniae and M. catarrhalis are the most common bacterial pathogens causing respiratory infections in children. Resistance to antibiotics may vary according to the geographical area. It is therefore important that the resistance pattern of such pathogens is determined by surveillance studies carried out both on a national scale and by individual laboratories.
In this study, we determined retrospectively the prevalence of H. influenzae, S. pneumoniae and M. catarrhalis in upper respiratory tract infections involving subjects of paediatric age, with reference to the type of clinical sample (pharingeal swab and nasal swab), symptomatology and age group. Moreover, for the above micro-organisms the pattern of sensitivity to antibiotics was assessed. In the observation period (January 1996-December 1999), at the day hospital of the Paediatric Pneumology Division of the Gaslini Institute in Genova, in 476 patients between 0 and 15 years of age a total of 460 respiratory pathogens were isolated: 164 S. pneumoniae strains, 163 of H. influenzae (96 belonging to type B and 67 non-attributable to any type) and 133 of M. catarrhalis.
As regards sensitivity to antibiotics, ceftriaxone and amoxycillin/clavulanic acid proved to be the most active molecules in all the studied strains.
High prevalence but low attack rate of HGV infection among patients with chronic hepatitis C
Stornaiuolo Gianfranca,
Di Biase Sebastiano,
Ascione Tiziana,
Labella Donato,
Apicella Nicola,
Sorrentino Annarita,
Pasquale Giuseppe,
Gaeta Giovanni Battista,
no surname no name
Objectives To determine 1. The prevalence and incidence of HGV infection in patients with chronic hepatitis C and 2. Its influence on the clinical outcome of chronic hepatitis C.
Patients and methods Sixty-five patients with non-parenteral chronic hepatitis C virus infection were investigated for HGV infection using the polymerase chain reaction for HGV-RNA and by detecting serum antibodies against the E2 protein of HGV (anti-E2 antibodies).
Results HGV-RNA in serum was found in 12 patients (18.4%) and anti-E2 antibodies in 4 (6.1%). No difference in age, sex, liver histology, basal ALT or GT was found between HGV positive and negative cases. Thirty-four patients (6 with HGV-RNA) were followed-up for 4 years; 4 of the 6 lost HGV-RNA, one of whom seroconverted to anti-E2. None of the 28 HGV-RNA negative cases presented HGV infection during the follow-up period. The presence of HGV infection did not influence either basal HCV viremia or the response of HCV to IFN therapy.
Conclusions The study demonstrated that HGV had an intense circulation through non-classic parenteral routes, but its impact on HCV replication and liver disease is negligible.
Case report
Ceftazidime in the treatment of Weil’s disease
Anselmo Marco,
De Leo Pasqualina,
Calcagno Giuseppe,
Donelli Emanuela,
Tirotta Angelito,
Menardo Giorgio
We present a case report of leptospirosis with acute renal failure and hepatic dysfunction. Aspecific clinical presentation and serologic tests do not help therapeutic choices. The patient received 18 sessions of hemodialysis and early treatment with intravenous ceftazidime 1 g tid (under the impression of Gram- sepsis). Third generation cephalosporins, ceftriaxone and cefotaxime, are highly active against Leptospira [10] while clinical experience with ceftazidime is lacking.
The Infections in the History of Medicine
The triumph of China China
Vannozzi Francesca
Malaria and its various remedies were frequently debated by Italian scientists in the 17th and 18th centuries. Physicians of the period discussed the probable origin of the disease, making use of the humoral theory, whilst upholding the efficacy of a new remedy, the bark of the cinchona tree. Knowledge of malaria, the various pathogenetic theories and some quite bizarre therapeutic attempts are amply documented in the medical literature of the age.
