Effect of dietary supplementation of Bifidobacterium and Lactobacillus strains in Apis mellifera L. against Nosema ceranae.

Nosema ceranae is a widespread microsporidium of European honeybee Apis mellifera L. affecting bee health. The ban of Fumagillin-B (dicyclohexylammonium salt) in the European Union has driven the search for sustainable strategies to prevent and control the infection. The gut microbial symbionts, associated to the intestinal system of vertebrates and invertebrates and its impact on host health, are receiving increasing attention. In particular, bifidobacteria and lactobacilli, which are normal inhabitants of the digestive system of bees, are known to protect their hosts via antimicrobial metabolites, immunomodulation and competition. In this work, the dietary supplementation of gut bacteria was evaluated under laboratory conditions in bees artificially infected with the parasite and bees not artificially infected but evidencing a low natural infection. Supplemented bacteria were selected among bifidobacteria, previously isolated, and lactobacilli, isolated in this work from healthy honeybee gut. Four treatments were compared: bees fed with sugar syrup (CTR); bees fed with sugar syrup containing bifidobacteria and lactobacilli (PRO); bees infected with N. ceranae spores and fed with sugar syrup (NOS); bees infected with N. ceranae and fed with sugar syrup containing bifidobacteria and lactobacilli (NP). The sugar syrup, with or without microorganisms, was administered to bees from the first day of life for 13 days. N. ceranae infection was carried out individually on anesthetised 5-day-old bees. Eight days after infection, a significant (P<0.05) lower level of N. ceranae was detected by real-time PCR in both NP and PRO group, showing a positive effect of supplemented microorganisms in controlling the infection. These results represent a first attempt of application of bifidobacteria and lactobacilli against N. ceranae in honeybees.

Effect of early antibiotic prophylaxis with ertapenem and meropenem in experimental acute pancreatitis in rats.

BACKGROUND: The clinical course in acute necrotizing pancreatitis is mainly influenced by bacterial infection of pancreatic and peripancreatic necrosis. The effect of two antibiotic treatments for early prophylaxis was studied in the taurocholate model of necrotizing pancreatitis in the rat. METHODS: Sixty male Sprague-Dawley rats were divided into three pancreatitis groups (15 animals each) and a sham-operated group (15 animals, control group). Pancreatitis was induced by intraductal infusion of 3% taurocholate under sterile conditions. Animals were placed on one of two different antibiotic regimens (15 mg/kg ertapenem or 20 mg/kg meropenem, one shot) after the induction of pancreatitis or received no antibiotics (control). All animals were sacrificed after 24 h to study pancreatic and extrapancreatic infection. RESULTS: Early antibiotic prophylaxis with either erapenam or meropenem significantly decreased pancreatic infection from 12/15 (control group) to 4/15 (ertapenem antibiotic group) and 3/15 (meropenem antibiotic group) (P < 0.05). CONCLUSIONS: In our animal model of necrotizing pancreatitis, early antibiotic prophylaxis with ertapenem and meropenem reduced bacterial infection of the pancreas. The efficacy of early antibiotic prophylaxis with ertapenem in the clinical setting should be subject to further research.

An active microbiological surveillance project at an Italian teaching hospital: microbial isolates, recent epidemiological trends, major clinical concerns, and antimicrobial susceptibility rates during a four-year period.

A microbiological surveillance program is currently performed at our tertiary-care teaching hospital. The temporal trend of microbial isolates from patients admitted during four calendar years (2004 to 2007) was analyzed according to the main bacterial and fungal culture organisms. The same pathogens isolated more than once from the same patient within one month were considered only once. On the whole, the main pathogen group remained that of Enterobacteriaceae (6,608 isolations out of 19,666: 33.6%, with Escherichia coli found in 60-75% of cases), with no significant difference over time. Staphylococci (4,150 isolates), and enterococci (3,276 isolates) were the two largest groups after Enterobacteriaceae, but staphylococci significantly declined during the four-year period (p .001), mainly due to progressively reduced isolation of coagulase-negative staphylococci. By contrast, a slight increase in enterococci occurred (p .05). Based on the frequency of isolation, Gram-negative oxidase-positive organisms accounted for 2,109 episodes, followed by other aerobic Gram-positive organisms other than Staphylococci-Enterococci (613 isolates), and anaerobes (583 isolates): no significant variations occurred over time for these last microbial groups. With regard to Gram-negative oxidase-negative microorganisms (567 isolates), non-beta-haemolytic streptococci (464 cases) and beta-haemolytic streptococci (260 isolates), a significant reduction of frequency occurred from 2004 to 2007 (p.05 to p.001). Finally, fungal infections accounted for 1,036 overall episodes, in over 80% of cases represented by Candida spp. Prospective microbiological monitoring is expected to contribute significantly to our knowledge of local epidemiological figures and antimicrobial sensitivity profile of hospital infections, and plays a major role in selecting both treatment and chemoprophylaxis schedules, especially on a local-regional basis. Although the major causative agents of in-patient infections remain Enterobacteriaceae, a significant decline in coagulase-negative Staphylococci, all Streptococci, and Gram-negative oxidase-negative organisms occurred over the four-year period, while Enterococci showed a mild increase over time.

Epidemiological, clinical and therapeutic features of AIDS-related Mycobacterium kansasii infection during the HIV pandemic: an 11-year follow-up study.

OBJECTIVES: Optimal diagnosis and timely treatment of atypical mycobacteriosis, and especially Mycobacterium kansasii disease, remain a serious challenge for clinicians engaged in the management of the immunocompromised host. METHODS AND RESULTS: From more than 2700 hospitalizations (over 1800 patients) attributable to HIV-associated disorders over an 11-year period, 12 patients were found to have a confirmed M. kansasii infection. This reflects the recent reduction in the frequency of this HIV-related complication, which virtually disappeared after the introduction of potent antiretroviral combinations in 1996. In the early 1990s, the lack of effective antiretroviral regimens made frequent the association with AIDS, a mean CD4 lymphocyte count of nearly 20 cells/microL, and an extremely variable chest X-ray features. The recent detection of a further case was attributable to late recognition of very advanced HIV disease, complicated by multiple opportunistic disorders. CONCLUSIONS: Mycobacterium kansasii respiratory or disseminated infection continues to occur, and poses diagnostic problems in terms of late or missed identification as a result of slow culture and frequently concurrent opportunistic disease. Serious therapeutic difficulties also arise from the unpredictable in vitro antimicrobial susceptibility profile of these organisms, and from the need to start an effective combination therapy that does not interfere with other medications as soon as possible.

Comparative evaluation of Sensititre YeastOne vs. the NCCLS M27A protocol and E-test for antifungal susceptibility testing of yeasts.

A recently developed microdilution method (Sensititre) YeastOne) may represent a valid alternative to the National Committee for Clinical Laboratory Standards (NCCLS) method for routine testing. The Medical Mycology Committee of the Associazione Microbiologi Clinici Italiani (AMCLI) decided to evaluate its reproducibility and reliability compared with the NCCLS M27A protocol and the E-test. Nineteen strains each of Candida albicans and Ca. parapsilosis, isolated from systemic infections, were tested against amphotericin B, flucytosine, ketoconazole, itraconazole, and fluconazole. All the participating laboratories tested the YeastOne panels, while the E-test and the NCCLS method were performed by two laboratories each. Interlaboratory reproducibility showed a good correlation (from 95% for amphotericin B to 92.5% for flucytosine). The agreement between NCCLS and YeastOne ranged from 95 (ketoconazole and itraconazole) to 100% (amphotericin B and flucytosine), whereas the agreement between E-test and YeastOne ranged from 72.5 (fluconazole) to 100% (amphotericin B and flucytosine). The Sensititre YeastOne panels appear to be an excellent alternative to both the E-test and the NCCLS protocol for antifungal susceptibility testing.

Using Apedin Vapor(R) in the control of Varroa mites and in honeybee feeding.

A new natural formula, Apedin Vapor(R) (water, ethanol 19%, lactose and plant extracts: Echinacea angustifolia, Thuya occidentalis, Spiraea ulmaria and Oxalis acetosella) is considered a honeybee feed and an acaricide against Varroa mites. Colonies in apiaries in Northern Italy were sprayed with 50 ml of a 1:2 solution. After seven administrations at 19-28 day intervals (24 May-5 October 2002), acaricide efficacy reached 19.8%. In another trial, three doses at three-week intervals (the first on 18 May) were administered. Mite mortality was 54.1% and 22.6% in treated colonies and controls, respectively. A noticeable amount of parasites survived the treatment in both trials. The number of adult honeybees and brood cells in each colony were estimated according to the Liebefeld method (modified) before and after the treatment periods. No significant differences were recorded between treated and control groups in each trial. No external reaction to the treatment was detected. Small groups of bees were fed 60% sugar syrup, 60% sugar syrup and ethanol (19%), ethanol (19%), water, Apedin and a 1:2 solution of Apedin. The 60% syrup uptake was 81.5 mg/bee over a period of 28 h. The presence of ethanol seemed to considerably decrease the syrup palatability (the uptake was only 19.4 mg). 2.3 mg, 2.9 mg, 2.7 mg and 2.7 mg of water, ethanol, pure and diluted Apedin were removed, respectively and 84.6%, 80.0%, 71.4%, 74.5% of the bees were found dead or showed clear symptoms of starvation. Furthermore, respectively 0% and 37.5% of the bees in the groups fed plain syrup and syrup to which ethanol had added were dead or nonreactively lying on the bottom of the cages because of the insufficient feeding. The possible side effects of lactose as an Apedin Vapor(R) component are discussed.

Frequency, epidemiology, risk factors, clinical and bacteriological features of enterococcal disease in patients with HIV infection in a decade survey.

In order to assess the frequency and clinical significance of Enterococcus spp. infection during HIV disease, the epidemiological features, risk factors, microbiological issues, and therapeutic perspectives of all the 148 consecutive episodes observed in the past decade were analyzed. The overall frequency of these complications (which involved the genito-urinary tract in over 75% of cases) regarded 5.3% of all admission for HIV disease, with a clear prevalence of Enterococcus faecalis as the causative agent (86.5% of episodes), and a proportionally elevated frequency of polymicrobial infection (45.9% of cases). Among the 148 cultured bacterial strains, a complete susceptibility to glycopeptide antibiotics was documented, together with favorable sensitivity levels against semisynthetic penicillins, followed by chloramphenicol, macrolides, and clindamycin. An advanced underlying HIV disease characterized by a concurrent, severe immunodeficiency, concomitant, prolonged neurological complications, hospitalization itself (with prevalence of nosocomial infection), recourse to invasive diagnostic and/or therapeutic procedures, and prior administration of broad spectrum antimicrobial agents, all seem to support HIV-associated enterococcal disease (mostly involving the genito-urinary tract). The adjunct of neutropenia, a very low CD4+ lymphocyte count, and severe AIDS-defining illnesses represented significant risk factors for hematogenous dissemination of this bacterial infection with potentially life-threatening consequences (16.1% of lethal cases among our septic patients).

Enterobacter spp. infections complicating the course of HIV disease.

Through a retrospective review of clinical and laboratory data of 2517 consecutive patients with HIV disease hospitalized since 1991, 13 patients were identified (0.52%), who suffered from a confirmed Enterobacter spp. infection (urinary tract disease in 7 cases, sepsis in 4 patients, and pneumonia in 2 cases). A severe immunodeficiency was recognized in all cases, as expressed by a mean CD4+ lymphocyte count <60 cells/microL, and frequently, a prior diagnosis of AIDS. Bloodstream infection proved linked to a lower mean CD4+ cell count, a more frequent occurrence of leukopenia-neutropenia, and nosocomial origin of the infecting pathogen. Hospital-acquired Enterobacter spp. disease was more frequent than community-acquired, and was significantly associated with leukopenia-neutropenia, and a diagnosis of AIDS. Antibiotic susceptibility assays showed a resistance rate to ampicillin and cephalothin involving >90% of tested strains, and a higher (but varied) sensitivity to other beta-lactams, aminoglycosides, fluoroquinolones, and cotrimoxazole. Adequate chemotherapy provided clinical and bacteriological success in all evaluated patients, in the absence of mortality or relapses. Only 34 episodes of HIV-associated Enterobacter spp. infection have been reported to date in 11 different literature studies. Our data point out that also Enterobacter spp. organisms may have an appreciable pathogenic potential in patients with HIV disease, especially in those with a low CD4+ lymphocyte count, leukopenia-neutropenia, who are hospitalized. Despite the unpredictable antibiotic susceptibility profile of these organisms, HIV-related Enterobacter spp. disease may be properly managed through rapid identification and timely and appropriate antimicrobial treatment.

Performance assessment of new multiplex probe assay for identification of mycobacteria.

A new DNA probe assay (INNO LiPA Mycobacteria; Innogenetics, Ghent, Belgium) for the simultaneous identification, by means of reverse hybridization and line-probe technology, of Mycobacterium tuberculosis complex, Mycobacterium kansasii, Mycobacterium xenopi, Mycobacterium gordonae, the species of the Mycobacterium avium complex (MAC), Mycobacterium scrofulaceum, and Mycobacterium chelonae was evaluated on a panel of 238 strains including, besides representatives of all the taxa identifiable by the system, a number of other mycobacteria, some of which are known to be problematic with the only other commercial DNA probe system (AccuProbe; Gen-Probe, San Diego, Calif.), and two nocardiae. The new kit, which includes a control probe reacting with the whole genus Mycobacterium, correctly identified 99.6% of the strains tested; the one discrepancy, which remained unresolved, concerned an isolate identified as MAC intermediate by INNO LiPA Mycobacteria and as Mycobacterium intracellulare by AccuProbe. In five cases, because of an imperfect checking of hybridization temperature, a very slight, nonspecific, line was visible which was no longer evident when the test was repeated. Two strains whose DNA failed amplification at the first attempt were regularly identified when the test was repeated. Interestingly, the novel kit dodged all the pitfalls presented by the strains giving anomalous reactions with AccuProbe. A unique feature of INNO LiPA Mycobacteria is its ability to recognize different subgroups within the species M. kansasii and M. chelonae, while the declared overlapping reactivity of probe 4 with some M. kansasii and Mycobacterium gastri organisms and of probe 9 with MAC, Mycobacterium haemophilum, and Mycobacterium malmoense, may furnish a useful aid for their identification. The turnaround time of the method is approximately 6 h, including a preliminary PCR amplification.

[Pathogenic role of Acinetobacter spp during HIV infection]. / Ruolo patogeno di Acinetobacter spp in corso di infezione da HIV.

In order to assess the clinical role of bacterial complications due to Acinetobacter spp. during HIV disease, a retrospective survey of clinical and microbiological data of 2221 HIV-infected patients hospitalised during the past 10 years was carried out, evaluating all episodes of Acinetobacter spp. infection according to several epidemiological, clinical and therapeutic variables. Eleven patients of 2221 (0.5%) suffered from Acinetobacter spp. disease: sepsis in 5 cases, and urinary, respiratory tract disease and bacteremic pneumonia in three, two, and one patient respectively. A. calcoaceticus was responsible in 4 cases, A. lwoffii in three, and Acinetobacter spp. in the 4 remaining cases; 4 patients experienced a polymicrobial infection, and 7 had a prior diagnosis of full-blown AIDS. All patients had a severe HIV-related immunodeficiency (mean CD4+ lymphocyte count 118.2 +/- 45.3 cells/microl). Compared with other localizations, sepsis was related to a lower mean CD4+ cell count (p<.001), and a more frequent occurrence of leucopenia-neutropenia (p<.005). Disease episodes diagnosed after the first 72 hours of hospitalisation (deemed no- socomial in origin), proved more frequent than community-acquired ones (9 cases versus 2), affected predominantly patients with AIDS and neutropenia, and were frequent1y associated with bacteremia (p<.04) The use of broad spectrum antibiotics, corticosteroids and cotrimoxazole, was recognized during the month preceding the diagnosis of Acinetobacter spp. disease, in 6, 4, and 8 cases, respectively. One patient only had an indwelling intravascular catheter, while no recent history of surgery, intensive care, or other invasive procedures was found. At in vitro susceptibility studies, bacterial isolates showed complete resistance to ampicillin and cephalothin, and low sensitivity to second-generation cephalosporins, while a higher susceptibility rate was revealed towards ceftazidime, netilmicin, amikacin, and quinolones, followed by cotrimoxazole and piperacillin. A prompt and appropriate antimicrobial therapy (mostly carried out with cephalosporins and aminoglycosides), led all patients to a clinical and microbiological cure within 6-1.3 days, in the absence of mortality or relapses. As opportunist pathogens with a predominant nosocomial origin, Acinetobacter spp. organisms may be responsible for an appreciable morbidity in patients with HIV disease, especially when additional risk factors (immunodeficiency, underlying diseases, and hospitalisation) are present. Notwithstanding the high drug resistance profile of the majority of isolated organisms, a timely diagnosis and a treatment based on in vitro assays, contribute to avoid recurrences and potentially life-threatening complications.

Histoplasma capsulatum var. capsulatum occurring in an HIV-positive Ghanaian immigrant to Italy. Identification of H. capsulatum DNA by PCR from paraffin sample.

Histoplasmosis, which is highly endemic in the United States, is rare in Europe, usually imported but sometimes autochthonous. In Africa, histoplasmosis capsulati coexists with "African histoplasmosis", a characteristic skin infection caused by H. capsulatum var. duboisii. Histoplamosis due to H. capsulatum is one of the 12 secondary infections listed in the surveillance definitions of AIDS. We report the case of a 36-year-old black man with acquired immunodeficiency syndrome (AIDS) who was living in Italy but originally came from Ghana. Histoplasmosis was disseminated with fever and cutaneous manifestations. The diagnosis was demonstrated morphologically based on the presence of yeast, observed by light microscopy, in skin lesions and by identification of H. capsulatum var. capsulatum DNA by nested PCR from a paraffin sample. No clinical reports of histoplamosis capsulati in Ghana have been published until now. The present case stresses the role of immigration of subjects from outside Europe who have been infected in their native country.

Acinetobacter infections in patients with human immunodeficiency virus infection: microbiological and clinical epidemiology.

BACKGROUND: We evaluated the role of complications caused by Acinetobacter spp. in the setting of HIV infection. METHODS: Clinical records of 1,923 consecutive HIV-infected patients hospitalized in a 9-year period were retrospectively reviewed, in order to identify all cases of Acinetobacter spp. complications, and to assess their occurrence and outcome according to several epidemiological, clinical and laboratory parameters. RESULTS: Ten patients out of 1,923 (0.52%) developed Acinetobacter spp. infections: sepsis in four cases, urinary tract infection in three, pneumonia in two and septicaemic pneumonia in the remaining patient. All patients were severely immunocompromised, as shown by a mean CD4+ lymphocyte count of 122 cells/microl and a frequent prior diagnosis of AIDS. As opposed to other infections, septicaemia was associated with a significantly lower CD4+ cell count and a more frequent occurrence of neutropenia. Hospital-acquired Acinetobacter spp. infections were significantly more frequent than community-acquired ones, and prevailingly involved patients with AIDS and leucopenia, being responsible for frequent blood dissemination. Antimicrobial, corticosteroid and cotrimoxazole treatment were frequently carried out during the month preceding disease onset. Antibiotic susceptibility studies proved the complete resistance of microbial isolates to ampicillin and cephalothin and poor sensitivity to second-generation cephalosporins and gentamicin, while greater susceptibility was shown to ceftazidime, netilmicin and amikacin, followed by piperacillin, cotrimoxazole and quinolones. Appropriate antimicrobial treatment led to clinical and microbiological cure in all cases, with no related mortality or relapses. CONCLUSIONS: Since only 23 episodes of HIV-associated Acinetobacter spp. infections have been described to date in 11 different reports (nine cases of bacteraemia, eight of pneumonia, two of urinary tract involvement, one of intravenous access device infection, one of meningitis and two with unspecified localization), our series represents the largest one dealing with HIV-associated Acinetobacter spp. infections. According to our experience, Acinetobacter spp. may be responsible for appreciable morbidity among patients with HIV infection, above all when a low CD4+ cell count, neutropenia and hospitalization are present. Clinicians and microbiologists who work in the field of HIV infection should consider the potential pathogenic role of Acinetobacter spp. organisms even in the absence of some presumed risk factors, because of the relationship between these infections and immunodeficiency, hospitalization, other infectious complications, prior antibiotic and steroid treatment and extended antimicrobial resistance patterns.

Moraxella catarrhalis pneumonia during HIV disease.

To assess the role of Moraxella catarrhalis complications in the setting of HIV disease, and to evaluate their occurrence and outcome according to several epidemiological, clinical, and laboratory parameters, the clinical records of 2123 consecutive HIV-infected patients hospitalized in a 9-year period were retrospectively reviewed, and 4 cases of community-acquired M. catarrhalis pneumonia were identified. Three adult patients had a diagnosis of AIDS and severe concurrent immunodeficiency (with a CD4+ lymphocyte count below 60 cells/microL), while the fourth case involved a child with vertical HIV disease. Leukopenia and neutropenia were never present, but no patient received a potent antiretroviral regimen at the time of disease onset. A concurrent respiratory infection by Streptococcus pneumoniae and Mycobacterium tuberculosis was recognized in 2 of 4 patients. Isolated M. catarrhalis strains were susceptible to all tested antimicrobial compounds (save ampicillin in 2 cases), and appropriate antimicrobial treatment led to clinical and microbiological cure in all described episodes. Only 8 cases of HIV-associated Moraxella spp. disease have been reported to date in seven different literature reports (6 cases of pneumonia, and 1 of septicemia). According to our experience, M. catarrhalis may be responsible for appreciable morbidity among patients with advanced HIV infection, especially when a low CD4+ cell count or coexisting respiratory disease are present. Clinicians and microbiologists who care for HIV-infected patients should carefully consider the potential pathogenic role of Moraxella spp. organisms.

An outbreak of Salmonella Hadar associated with roast rabbit in a restaurant.

In August 1997, an outbreak of gastroenteritis from Salmonella Hadar phage type 2 occurred among customers of a restaurant in Rimini (Emilia-Romagna region, Italy). Twenty-nine people who had eaten food prepared in the restaurant on 2 or 3 August had symptoms of acute gastroenteritis. The infection was culture-confirmed in 24 cases and the stool specimens of four healthy people were positive for Salmonella Hadar. Twelve people had to be hospitalized and a 3-year old girl died. The case-control study identified roast rabbit as the likely vehicle of infection (OR: 6.00; CI 95%: 1.65-22.83). The microbiological investigation carried out on food taken from the restaurant confirmed high levels of Salmonella Hadar in a sample of roast rabbit. Since the rabbit was well cooked, the food contamination likely occurred after cooking. Poor hygienic conditions found in the restaurant, together with inappropriate food-handling practices and inadequate storage temperatures may have contributed to spread to other foods and the severity of the outbreak.

Clinical and microbiological survey of Serratia marcescens infection during HIV disease.

Clinical charts of 2,398 consecutive HIV-infected patients hospitalized over an 8-year period were reviewed retrospectively to identify all cases of Serratia infection and to evaluate the occurrence and outcome of these cases according to several epidemiological. clinical, and laboratory parameters. Seventeen of 2,398 (0.71%) patients developed Serratia marcescens infections: nine had septicaemia, six had pneumonia, one had a lymph node abscess, and one had cellulitis. All patients were severely immunocompromised, as evidenced by a mean CD4+ lymphocyte count of < 70 cells/microl and a frequent diagnosis of AIDS (13 patients). When compared with other disease localizations, septicaemia was related to a significantly lower CD4+ cell count and a more frequent occurrence of neutropaenia. Antibiotic, corticosteroid, or cotrimoxazole treatment was frequently carried out during the month preceding disease onset. Hospital-acquired Serratia spp. infection was more frequent than community-acquired infection and was significantly related to AIDS, neutropaenia, and sepsis. Antimicrobial sensitivity testing showed complete resistance to ampicillin and cephalothin but elevated susceptibility to ureidopenicillins, second- and third-generation cephalosporins, aminoglycosides, quinolones, and cotrimoxazole. An appropriate antimicrobial treatment attained clinical and microbiological cure in all cases, in absence of related mortality or relapses. Since only 13 episodes of HIV-associated Serratia spp. infection have been described until now in nine different reports (7 patients with pneumonia, 3 with sepsis, 1 with endophthalmitis, 1 with perifolliculitis, and 1 with cholecystitis), our series represents the largest one dealing with Serratia marcescens infection during HIV disease. Serratia marcescens may be responsible for appreciable morbidity among patients with HIV disease, especially when a low CD4 + cell count, neutropaenia, and hospitalization are present. The clinician and the microbiologist facing a severely immunocompromised HIV-infected patient with a suspected bacterial disease should consider the Serratia spp. organisms. In fact, a rapid diagnosis and an adequate and timely treatment can avoid disease relapses and mortality.

Pseudomonas spp. complications in patients with HIV disease: an eight-year clinical and microbiological survey.

Two hundred and twenty-four episodes of Pseudomonas spp. complications that occurred in 179 consecutive patients with HIV infection were retrospectively reviewed. Pseudomonas spp. organisms were responsible for 11.6% of 1933 episodes of non-mycobacterial bacterial diseases (5.4% of 1072 episodes of sepsis), observed over an 8-year period; 20.7% of patients experienced disease relapses (45 episodes). These complications mostly involved lower airways (66 cases), urinary tract (53 episodes), and blood (34 cases), with Pseudomonas aeruginosa isolated in 161 episodes, and other Pseudomonas spp. in the remaining 63 cases. An advanced HIV disease was frequently present (as expressed by a prior diagnosis of AIDS, a low CD4+ lymphocyte count, and leukopenia-neutropenia). Indwelling intravascular and urinary catheters were often associated with bacteremia and urinary tract involvement, respectively. More than 60% of patients were given antibiotics and/or cotrimoxazole in the month preceding the onset of Pseudomonas spp. disease. Bacterial strains isolated from our HIV-infected patients showed a favorable sensitivity to piperacillin, ceftazidime, imipenem, amikacin, tobramycin, and ciprofloxacin. An adequate antimicrobial treatment led to clinical and microbiological cure in 73.2% of patients at the first episode, and in 22.3% more subjects after one or more relapses. A lethal outcome occurred in only eight patients of 179 (4.5%), suffering from a far advanced HIV disease; P. aeruginosa infection directly contributed to death in four cases (sepsis, and/or pneumonia). Nosocomial disease occurred in 46.4% of the 224 episodes, and was significantly related to a previous diagnosis of AIDS, concurrent neutropenia, the occurrence of sepsis or urinary tract infection, disease relapses, the involvement of non-aeruginosa Pseudomonas spp., and a lethal outcome, compared with community-acquired infection. Our experience (the largest reported to date) confirms that Pseudomonas spp. (including non-aeruginosa Pseudomonas spp. organisms) is responsible for remarkable morbidity and mortality among patients with HIV infection, and may pose relevant problems to clinicians and microbiologists involved in the care of HIV-infected patients.

Histopathological evidence of North American blastomycosis in Italy: report of two cases.

No clinical reports of blastomycosis in Italy have been published until now. We here report two cases of histologically diagnosed, unexpected cutaneous involvement in patients, aged 78 and 52 years, living in North Italy and never having been abroad. The histological differential diagnosis between blastomycosis and other fungal pathogens is discussed. Even in the absence of culture the present cases can confidently be considered as genuine examples of Blastomyces dermatitidis infection in Italy.

Flavobacterium spp. organisms as opportunistic bacterial pathogens during advanced HIV disease.

OBJECTIVE: To assess the role of Flavobacterium spp. infection in patients with HIV disease. METHODS: Clinical charts of 2412 consecutive HIV-infected patients hospitalized in a 8-year period were retrospectively reviewed, to identify all cases of Flavobacterium spp. infections, and to evaluate their occurrence and outcome according to several epidemiological, clinical, and laboratory parameters. RESULTS: Six patients out of 2412 (0.25%), developed Flavobacterium spp. complications: septicaemia in five cases, and pneumonia in the remaining patient, with F. meningosepticum and F. odoratum isolated in two cases and one case, respectively, and unnamed Flavobacterium spp. organisms in the remaining three cases. Flavobacterium spp. organisms were responsible for six out of 1939 overall episodes of non-mycobacterial bacterial diseases observed in our patient group (0.31%). All patients were severely immunocompromised, showing a prior diagnosis of AIDS, a mean CD4+ lymphocyte count of 64.2 (range 12-187) cells/microl, and a mean neutrophil count of 1.143 (range 700-1600) cells (range 700-1600) cells/microl. Antibiotic, corticosteriod, or cotrimoxazole treatment was carried out during the month preceding disease onset by three, two and five patients, respectively. Community-acquired and nosocomial Flavobacterium spp. disease were equally frequent, but the latter occurred with a significantly lower mean neutrophil and CD4+ cell count. Antimicrobial susceptibility assays showed complete sensitivity to ciprofloxacin, and variable resistance to ureidopenicillins, ceftazidime, imipenem, aztreonam, and aminoglycosides. An appropriate antimicrobial regimen obtained clinical and microbiological cure in all cases, in absence of related mortality or relapses. CONCLUSIONS: Since only one episode of HIV-associated F. (Sphingobacterium) multivorum complication has been described to date, our series represents the largest one dealing with Flavobacterium spp. infection in the setting of HIV disease. Our experience suggests that Flavobacterium spp. organisms may play a pathogenic role in patients with advanced HIV disease, even when some commonly recognized risk factors are lacking (i.e. indwelling catheters, instrumentation, IV drug abuse), while a very low CD4+ lymphocyte count, leukopaenia-neutropaenia, and concurrent AIDS-related infectious complications may act as important predisposing factors. In view of the infrequent occurrence of these infections, early suspicion is essential for both clinicians and microbiologists facing immunocompromised patients at risk for invasive bacterial complications. Flavobacterium spp. organisms should be taken into consideration as nosocomial- or community-acquired opportunistic pathogens, due to their relationship with advanced immunodeficiency and their elevated resistance to many antimicrobial agents commonly used against Gram-negative bacterial pathogens.

Emerging gram-negative pathogens in the immunocompromised host: Agrobacterium radiobacter septicemia during HIV disease.

Three out of 2,412 consecutive HIV-infected patients hospitalized since 1990, developed Agrobacterium radiobacter septicemia. All patients were severely immunocompromised, showing a prior diagnosis of AIDS, concurrent opportunistic infections, a mean CD4+ lymphocyte count below 100 cells/microL, and neutropenia. Nosocomial A. radiobacter sepsis occurred in two cases of three, and was related to a lower neutrophil and CD4+ cell count. Antibiotic and cotrimoxazole treatment were carried out during the month preceding disease onset by two and three patients, respectively. Antimicrobial susceptibility assays showed resistance to ureidopenicillins and aztreonam, and complete sensitivity to carbapenems, amikacin, and ciprofloxacin. A therapeutic regimen including amikacin plus ceftriaxone or ceftazidime obtained clinical and microbiological cure in all cases, in the absence of related mortality or relapses. Only two episodes of HIV-associated A. radiobacter complications have been described to date: one case of sepsis and one patient with pneumonia. Despite their low frequency, gram-negative non-fermenting bacilli should be considered in HIV-infected patients with a suspected bacterial complication, because of their cumbersome identification procedures, and their unpredictable antibiotic susceptibility, with elevated resistance to many compounds expected to be effective against gram-negative organisms. A. radiobacter may play a pathogenic role in patients with advanced HIV disease, even when some commonly recognized risk factors are lacking (in-dwelling catheters and instrumentation), while a very low CD4+ lymphocyte count, leukopenia-neutropenia, hospitalization, and concurrent AIDS-related infectious complications, may act as predisposing factors.