Volume 5, Issue 1, 1997
Review
Nosocomial infections: back to the future
Menichetti Francesco
The increasing rate of nosocomial infections seems to be related to the wider use of invasive procedures. Evaluation of the patient risk factors for infection, use of SIRS classification and knowledge of the setting care should be utilized for the diagnostic approach. The empiric antibiotic therapy should take in account the site of the infection (bacteremia, pneumonia, urinary tract infection etc.) and the presumed pathogen; knowledge of the local epidemiology is a pre-requisite for the antibiotics choice. Among gram-positive microrganisms, methicillin-resistant staphylococci and vancomycin-resistant enterococci are responsible of difficult to treat infections; penicillin-resistant pneumococci, largely present in some european countries, might become an emerging pathogen also in Italy. The knowledge and ability of infectious diseases specialist encompasses clinical, microbiological and epidemiological fields to play a key role in the prevention and management of nosocomial infections.
Hepatic Encephalopathy. Pathogenesis and Therapy
Felaco Francresca Maria,
Pagliano Pasquale
Hepatic encephalopathy is a frequent complication of cirrhosis. Portal-systemic shunts and depression of hepatic function are the primary underlying abnormalities. Arterial blood ammonia levels are frequently elevated during hepatic encephalopathy and are lower when a clinical improvement is established. Glutamine synthesis is part of the metabolic pathway for ammonia cerebral detoxification that induces ATP and glutamate (excitatory neurotransmitter) depletion. Plasma levels of branched chain amino acids are reduced in patients with cirrhosis, this event allows aromatic amino acids to cross the emato-liquoral barrier through exchange with glutamine. Cerebral excess of aromatic amino acids promotes the synthesis of octopamine and feniletiletanolamine, weak neurotransmitters. Benzodiazepine-like substances may affect GABA-ergic transmission by interacting with their receptors on the GABA-benzodiazepine complex. Therapy is aimed at controlling the events that may precepitate the acute encephalopathy, at reducing the ammonia levels, and correcting the neurotransmission abnormalities.
Original article
Bacterial infections in HIV patients
Carrega Giuliana,
Santoriello Luisa,
Bartolacci Valentina,
Guerra Michele,
Varagona Giuseppe,
Riccio Giovanni
Aim of the study and methotds: retrospective analysis of bacterial infections occuring in 400 admissions of HIV-positive patients in the Infectious Diseases Unit of the Azienda Ospedale Santa Corona, Pietra Ligure (SV), from January 1994 to September 1996.
Results: 56 episodes were documented (14% of admissions): 24 (43%) hospital acquired (11 sepsis, 5 pneumonias, 6 urinary-tract infections, 1 infection of a prosthetic device) and 32 (57%) community-acquired (9 sepsis, 13 pneumonias [6 with bacteremia] 9 urinary-tract infections, 1 endocarditis). At time of diagnosis mean absolute CD4-lymphocyte count was 106/cmm (95% Cl 62-150) and mean neutrophil count was 4.690/cmm (95% Cl 3.466-5.914); 11 patients had a central venous catheter, 9 a vescical catheter and 7 severe skin lesions. Methicillin-resistant S. aureus (11/24, 46%) and Pseudomonas (8/24, 33%) were the most frequently isolated pathogens in hospital infections, while the majority of community acquired episodes were due to S. pneumoniae (10/32, 31%). In six episodes (11%) the patient died because of the bacterial infection.
Conclusions: bacterial infections are quite frequent in this cohort of HIV-infected patients. Methicillin-resistant S. aureus and Pseudomonas represented the major cause of hospital acquired infections, while S. pneumoniae represented the major cause of community acquired episodes.
Bacteraemia in patients with HIV disease: aetiological spectrum and profile of antimicrobial susceptibility
Manfredi Roberto,
Nanetti Anna,
Ferri Morena,
Mastroianni Antonio,
Coronado Olga,
Chiodo Francesco
A retrospective survey of non-opportunistic bacterial pathogens isolated from blood cultures of patients with HIV disease has been carried out for a 6-year period, and the antibiotic susceptibility of the 748 microorganisms cultured from 682 consecutive patients, has been evaluated. Gram-positive organisms significantly prevailed over gram-negative ones, with Staphylococcus aureus, coagulase-negative staphylococci, Enterococcus faecalis, Xantomonas maltophilia, Salmonella and Pseudomonas sp. as the most common isolates, and Rhodococcus equi, Serratia, Acinetobacter and Alcaligenes sp. as emerging pathogens. Useful suggestions may be obtained for empiric antimicrobial treatment of suspected sepsis in HIV-infected patients, from the evaluation of the antibiotic susceptibility profile of these non-opportunistic bacterial pathogens.
Biochemical response to interferon of chronic hepatitis in drug-addict patients infected with human immunodeficiency virus
Nardiello Salvatore,
Pizzella Teresa,
Gargiulo Miriam,
Gramenzi Annagiulia,
Digilio Laura,
Di Ottavio Licia,
Galanti Bruno
The effects of IFN treatment were retrospectively evaluated for 18 drug-addict patients with symptomatic HIV infection and chronic hepatitis C. Most of the patients were receiving concomitant treatment with zidovudine. Seven out of the 18 patients (39%) stopped IFN after less than three months, most of them for non-compliance. Among the 11 patients who completed a 6-12 month period of IFN treatment, 3 (27%) normalized and maintained normal ALT levels during therapy: for 2 of them the response was sustained after IFN discontinuation. The response to IFN therapy was neither correlated to the CD4+ levels nor to the clinical stage of the HIV infection. Instead, the response seemed to be influenced by pre-therapy ALT levels and liver histology. Tolerance to IFN treatment was good. These data show that IFN may be indicated in the therapy of chronic HCV infection for HIV-positive patients.
Susceptibility of P. aeruginosa and enterobacteriaceae isolated from 1986 to 1994 in the microbiology laboratory of the Infectious Diseases Institute of Perugia University
Pasticci Maria Bruna,
Baldelli Franco,
Moretti Amedeo,
Cardaccia Angela,
Pauluzzi Sergio
From 1986 to 1994, 812 P. aeruginosa, 1997 E. coli, 437 P. mirabilis, 400 Klebsiella spp., 238 Enterobacter spp., 130 Serratia spp. strains were isolated from clinical materials in the Microbiology laboratory of the Infectious Diseases Institute of Policlinico Monteluce, Perugia University. During the study period the Authors observed the following variations in the susceptibility patterns: increased resistance of P. aeruginosa to piperacillin from 20.8% to 27.2% (P<0.05), amikacin from 11.9% to 17.5% (P<0.05), netilmicin from 11.8% to 28.6% (P<0.01), pefloxacin from 74.4% to 87.8% (P<0.01); E. coli to norfloxacin, ciprofloxacin and pefloxacin, respectively from 1.3% to 3.6% (P<0.001), from 1.5% to 3.6% (P<0.05) and from 3.2% to 9% (P<0.001); Serratia spp. to ceftazidime from 14% to 33.3% (P<0.05); Enterobacter spp. to norfloxacin from 5.1% to 13.6% (P<0.05), cotrimoxazole from 12.8% to 23.5% (P<0.05) and chloramphenicol from 19.4% to 31.8% (P<0.05). Moreover cephalotin resistant strains of E. coli decreased from 29.3% to 21.3% in the last 4 years (P<0.001).
Survival time of AIDS patients resident in Bologna city and county. Reccomandations for care planning
Sabbatani Sergio,
Di Crescenzo Ettore,
Zanna Simona
The authors have analyzed the survival time of AIDS patients (resident in Bologna) in the period from 1984 to 1995. The study can allow accurate predictions to be made as to the likely volume of admissions to in-patients wards and Day Hospital, as well as helping Home Care planning for patients with serious social problems. The case histories studied were of 752 adult AIDS patients and 13 children. The adult AIDS patients had a mean survival time of 10.4 months (range 9.6-11.8). By breaking down the case histories into those notified between 1984 and 1987, 1988 and 1991 and 1992 and 1995, the greatest increase of survival time (mean) with respect to the previous four years period was achieved in the period covering 1988-1991: 5.23 months against 10.53 months (p<0.05). The life expectancy of persons above 40 years of age is lower than in the case of younger patients: 7.7 months against 11.37 months in the age bracket 26-39 years (P<0.05). The child cases of AIDS showed a survival time of 31.4 months (range 11.1-55.9).
“In vitro” susceptibility of group A beta-haemolytic streptococcus
Noviello Silvana,
Ianniello Filomena,
Esposito Silvano
An epidemiological survey on 827 pediatric patients has been performed from march ‘95 to november ‘96 to verify the incidence of streptococcal etiology during acute pharyngo tonsillitis in pediatric age and the “in vitro” susceptibility of the group A beta hemolitic Streptococcus isolates.
S. pyogenes was responsible of acute pharyngo tonsillitis in 32.7% of cases. No strain was resistant to beta lactams, but resistance to erithromycin was high (38.7% of bacterial isolates). These results suggest the importance of a constant epidemiological surveillance of bacterial resistance of S. pyogenes in the community setting.
Case report
Septic arthritis in the setting of HIV disease. A case report and literature review
Manfredi Roberto,
Legnani Giorgio,
Mastroianni Antonio,
Coronado Olga,
Chiodo Francesco
A case of septic arthritis due to Haemophilus influenzae is described in a HIV-infected patient. Even though complicated by large effusion and extensive subcutaneous involvement, the clinical picture showed a favourable outcome after prolonged ceftriaxone treatment, leading to complete cure. The case report is discussed with respect to both other bacterial complications caused by H. influenzae in the setting of HIV disease, and the broad aetiological spectrum of HIV-associated acute arthritis. In particular, no other cases of H. influenzae purulent arthritis have been described until now in patients with HIV disease, at our best knowledge.
