Major bacterial infections following liver transplantation: a prospective study.

The incidence and characteristics of major bacterial infections were studied prospectively in 50 consecutive adult patients who underwent liver transplantation (LT). All patients received the same protocol of immunosuppression, bowel decontamination, antibiotics prophylaxis, and follow-up. Thirty-two patients (64%) had at least one episode of major bacterial infection. One death was directly related to a bacterial infection, accounting for 13% of postoperative mortality. The most critical period for infection was the first 2 months after surgery, when 69% of the infections occurred. The most frequent clinical presentations were bacteremia, pneumonia and abdominal abscesses. Eighty percent of the bacteremias had an identifiable source, the most frequent being intravascular catheters. Gram-positive microorganisms (69%) predominated over gram-negative rods (26%) and anaerobes (5%). The use of selective bowel decontamination (SBD) with norfloxacin may explain this predominance. Major bacterial infections are an important source of morbidity and mortality after LT. Efforts to prevent these infections and to determine their source and specific treatment, will improve the management and the outcome of these patients in the future.     

Microepidemics of tuberculosis: the stone-in-the-pond principle.

In a low prevalence country with no systematic BCG vaccination and a low frequency of environmental mycobacterial infections, for each recognized case of tuberculosis or infection with M. tuberculosis source detection should be undertaken. Sometimes this search will lead to discovery of a microepidemic. The extent of contact screening in a microepidemic can easily be determined if observed group prevalences are compared to expected group prevalences. The described method illustrates this search for contacts in concentric circles around the source case: the stone-in-the-pond principle.     

Nosocomial aspergillosis is waterborne.

Nosocomial invasive aspergillosis can cause life-threatening infections among immunosuppressed patients and is thought to be primarily airborne. Despite the use of appropriate hospital air filtration systems, however, the incidence of this infection continues to increase. In this article, we present our hypothesis, which is that nosocomial aspergillosis can be airborne from a water source in the hospital. If confirmed by ongoing studies, this hypothesis would imply a change in the current infection control practices aimed at preventing nosocomial aspergillosis.     

Resolution of organ-specific complications of human immunodeficiency virus infection in children with use of highly active antiretroviral therapy.

Opportunistic infections are a major source of morbidity and mortality in children and adults infected with human immunodeficiency virus (HIV). In addition, organ-specific complications of HIV infection, such as cardiomyopathy, nephropathy, encephalopathy, and others, contribute substantially to the morbidity and mortality associated with HIV infection. Highly active antiretroviral therapy (HAART) has produced a dramatic decline in the incidence of opportunistic infections among patients with HIV infection. Nevertheless, there is very little information concerning the value of HAART for organ-specific complications of HIV infection. In this report, we describe 3 children with HIV infection in whom the dominant clinical manifestations were cardiomyopathy, red cell aplasia, and nephropathy. HAART produced a decrease in the HIV ribonucleic acid level, an increase in the CD4 cell count, and resolution of the organ-specific complications in all patients. These cases add to our knowledge concerning the benefits of HAART for children with HIV infection.     

Hepatitis B: evolving epidemiology and implications for control.

Control and the possible elimination of transmission of HBV infection is possible with the appropriate use of hepatitis B vaccines. The prevention of chronic HBV infection has the potential of reducing the association burden of chronic liver disease and primary hepatocellular carcinoma. Worldwide, strategies for the effective use of hepatitis B vaccine have been developed and are being implemented in those areas where childhood transmission is the predominant source of chronic HBV infections. However, in the United States and other areas with "low" rates of HBV infection, current vaccination strategies have not been effective and have not fully taken into account the multifaceted epidemiology of HBV infection in those areas. Unfortunately, the majority of infections occur among adults who have been the most difficult to access, who acquire infection before they realize they are at risk, and where the changing epidemiology of HBV infections among the various risk groups only emphasizes the problems of vaccine delivery. In addition, the majority of persons receiving vaccine as a result of the current strategy to immunize adult high-risk groups have been persons who acquire HBV infection through occupational exposure, a group that accounted for no more than 5% of cases even before vaccine was introduced. The failure of the current immunization strategy to prevent a disease with significant health care and economic consequences is beginning to cause a reevaluation of this approach. A comprehensive approach to eliminating HBV transmission must address infections acquired during early childhood as well as those acquired by teenagers and adults.(ABSTRACT TRUNCATED AT 250 WORDS)     

Community-acquired invasive group A beta-hemolytic streptococcal infections in Zuni Indians.

BACKGROUND--Outbreaks of invasive group A beta-hemolytic streptococcal (GABS) infections have recently been reported. We observed a high incidence of invasive GABS disease among Native Americans at a small rural community hospital between 1982 and 1991. METHODS--A retrospective chart review was performed, and all cases of invasive GABS disease were studied for their clinical features. RESULTS--Sixteen cases of invasive GABS infection were identified during the 10-year study period. The rate of invasive GABS infection was 13.3 cases per 100,000 population per year. Mortality was 25%. Nearly half of the patients presented with systemic signs of sepsis without any obvious source of infection. CONCLUSIONS--Our experience documents a high rate of invasive GABS infections in a defined Native American population. To determine whether this population has a unique susceptibility to GABS disease requires further study.     

Mycoses in the genital area. I. Yeast mycoses

Yeast infections are of primary importance in genital pathology; the most common, but by no means the sole pathogen, is Candida albicans. The incidence of yeast infections is seasonal in nonpregnant women, while in pregnant women it rises markedly during the third trimester. This is the main source of infection for oral candidosis of the newborn. Incidence is also increased in women treated with oral contraceptives. Yeast infections also occur in men, and seem to be encouraged by the use of antibiotics. Antimycotic drugs of great efficiency have been developed recently, but positive identification of the pathogen is a prerequisite to effective therapy.     

An outbreak of Serratia marcescens in 14 adult cardiac surgical patients associated with 12-lead electrocardiogram bulbs.

Two clusters of Serratia marcescens in 14 adult cardiac surgical patients occurred over 10 months in an 876-bed teaching hospital. The 14 infections that were studied were as follows: one sternal and five leg incisions, five pneumonias, one bacteremia, one urinary tract infection, and one infected internal defibrillator site. The first cluster included four pneumonias, one urinary tract infection, and one bacteremia. Corrective actions were taken based on outbreak data through no source was identified. No further infections occurred during the following 2 months. The second cluster included one sternal and five leg incisions, an infected internal defibrillator incision site, and one pneumonia. Serratia marcescens was isolated from six electrocardiogram rubber welsh bulbs with sensitivities identical to patient isolates that indicated a common source outbreak in at least the second cluster of infections. Disposable electrocardiogram leads were introduced and the problem was resolved. We conclude that reusable electrocardiogram welsh bulbs are a vector for postoperative infections.     

Epidemiology of bacterial hand infections.

OBJECTIVE: The aim of the study was to delineate and update the bacteriological spectrum, characterize patterns and sites of injury, evaluate laboratory tests and possible causes of complications in patients with bacterial hand infections. METHODS: All hand infections operated on in the department of orthopedics at Odense University Hospital during the period 1992-2001 were reviewed retrospectively. A standard protocol was used to collect data for each patient. We also examined all laboratory reports and recorded the identity of the etiologic organism, if known, for all cases of bacterial hand infections. RESULTS: Four hundred and eighteen patients (296 men and 122 women) with hand infections were operated on between 1992 and 2001 in our department. The median age of the patients was 40 years (range 1-93). The average interval from primary injury to operation was 10 days (range 1-50). The etiology was laceration/puncture in 35%. The site of infection was subcutaneous in 45% followed by tendon, joint and bone in 27, 18 and 5%, respectively. The bacteria isolated from the patients showed that 184 cultures (44%) were pure Staphylococcus aureus followed by 49 cultures (11.7%) of mixed organisms. Body temperature and C-reactive protein (CRP) were normal in three quarters of all patients with hand infections in our series. However the erythrocyte sedimentation rate (ESR) was elevated in 50% of the patients and was a significantly better test for infection in this study than CRP (p = 0.002). Neither the severity of infection nor the etiology of infection was related in any way to the initial temperature, CRP or ESR in this study. Complications were noted in 14.8% of all patients, and were especially related to diabetes, and mixed infection. CONCLUSION: Despite modern antibiotics, hand infections with a variety of organisms continue to be a source of morbidity and possible long-term disability. Most hand infections are the result of minor wounds that have been neglected. A complete history and physical examination is necessary to exclude other associated medical conditions (diabetes, arthritis, immunosuppression) that may compromise therapy. Furthermore, our study confirms that Staphylococcus aureus is responsible for most instances of hand infection, followed by mixed organisms. Gram-negative organisms are frequently cultured in patients with diabetes and intravenous drug abuse.     

Sexually transmitted diseases in mothers of neonates with congenital cytomegalovirus infection.

To identify maternal risk factors for intrauterine transmission of cytomegalovirus (CMV), a case-control study of 175 mothers of neonates with congenital CMV infection was undertaken. Cases and 358 randomly selected controls delivered neonates between 1980 and 1988; in this interval neonates were routinely tested for viruria. Eighty-four percent of the study population was black and greater than 87% received prenatal care. Women with gonorrhea, trichomoniasis, or bacterial vaginosis had an increased risk of intrauterine transmission of CMV, as did those who were primigravid (odds ratios, 1.8-2.5). Women who were young, unmarried, and of lower income were almost four times more likely to deliver a CMV-infected newborn than were those who did not have all three of these factors. These results in a predominantly black, low-income population indicate a greater risk for congenital CMV infection in offspring of young, single, primigravid mothers. The association with gonorrhea and other sexually transmitted infections suggests that sexual activity is an important source of maternal CMV infections that result in congenital infection in this population.     

Drugs five years later. Spectinomycin.

A single intramuscular injection of 0.2 g of spectinomycin hydrochloride is highly effective for the treatment of uncomplicated anogenital infections with Neisseria gonorrhoeae. Spectinomycin hydrochloride is indicated for uncomplicated anogenital gonococcal infections in men and women who cannot receive penicillin or probenecid, and is the drug of choice for the retreatment of patients with uncomplicated anogenital gonococcal infection who have not responded to other antibiotics. A single dose of spectinomycin does not appear to be reliably effective in the treatment of gonococcal pharyngitis. Preliminary reports indicate that multiple-dose schedules of spectinomycin will prove to be effective in gonococcal pelvic inflammatory disease and disseminated gonococcal infection. In the dosage used for gonococcal infections, spectinomycin has little effect on infection with Treponema pallidum. Evaluation of this antibiotic against other microorganisms suggests little utility for this agent in conditions other than gonococcal infections.     

Prevention of catheter-related infections using a closed hub system in patients with pulmonary arterial hypertension.

BACKGROUND: Most of the patients with pulmonary arterial hypertension (PAH) receiving intravenous epoprostenol have experienced catheter-related infections during long-term treatment. Catheter hub was reported to be the most important source of catheter-related infections. To prevent the catheter-related infections, we have introduced a closed hub system and compared the incidence of catheter-related infections with that in patients using a non-closed hub system. METHODS AND RESULTS: We evaluated the results obtained on 24 occasions in 20 patients with PAH between June 1999 and December 2005. On 11 occasions, a non-closed hub system was used and on 13 cases a closed hub system. We classified the catheter-related infection into a catheter-related bloodstream infection (CRBSI) group or a tunnel infection group based on the pathway of bacteria. The CRBSI rate was 0.89 per 1,000 catheter days in the non-closed hub system group vs 0.10 per 1,000 catheter days in the closed hub system group. Kaplan-Meier analysis showed that the risk of CRBSI significantly decreased in the closed hub system group. None of the patients died as a direct consequence of catheter-related infection during the study period. CONCLUSIONS: We successfully prevented CRBSI by using a closed hub system.     

Urinary tract infection in long-term-care facility residents.

Urinary tract infection is the most frequent bacterial infection in residents of long-term-care facilities. Most infections are asymptomatic, with a remarkable prevalence of asymptomatic bacteriuria of 15%-50% among all residents. The major reasons for this high prevalence are chronic comorbid illnesses with neurogenic bladder and interventions to manage incontinence. Prospective, randomized, comparative trials of therapy and no therapy for asymptomatic bacteriuria among nursing home residents have repeatedly documented that antimicrobial treatment had no benefits. However, there is substantial diagnostic uncertainty in determining whether an individual with a positive urine culture has symptomatic or asymptomatic infection when there is clinical deterioration and there are no localized findings. In the noncatheterized resident, urinary infection is an infrequent source of fever but may not be definitively excluded. The use of antimicrobials for treatment of urinary infection is part of the larger concern about appropriate antimicrobial use in long-term-care facilities and the impacts of the selective pressure of antimicrobials on colonization and infection with resistant organisms.     

Prospective study of prevalence, incidence, and source of herpesvirus infections in patients with renal allografts.

The prevalence, incidence, and source of infections with different types of herpesviruses were determined prospectively for 25 persons undergoing hemodialysis, 30 allograft recipients, and 16 kidney donors. The prevalence of prior infections with cytomegalovirus (CMV), herpes simplex virus (HSV), and Epstein-Barr virus (EBV) was high (72%-100%) and was similar for healthy persons and those with renal failure. The incidence of infections in patients undergoing hemodialysis was no greater than that before dialysis. In allograft recipients, the incidence of infection with CMV was 73%; HSV, 57%; EBV, 30%; and varicella-zoster virus (clinical), 7%. Ninety-seven percent of the patients developed an infection with one or more herpesviruses. Transfusions, hemodialysis, the allograft, and hospital environment were not significant sources in transmission. Uremia and splenectomy were unimportant in the reactivation of infection. Immunosuppressive drugs possibly algmented by a graft rejection response account for the high incidence of recrudescent infections with CMV and HSV.     

Fungal infections in AIDS. Histoplasmosis and coccidioidomycosis

Histoplasma capsulatum and Coccidioides immitis are two fungi that are regional in occurrence and cause opportunistic fungal infections in patients with AIDS. Many cases of histoplasmosis have been reported in patients months or years after they have been in an endemic area. These are obviously cases of reactivation of latent infections. With coccidioidomycosis, the cases have been reported from endemic areas, but some also appear to be reactivation infections, and we should anticipate such cases in nonendemic areas just as with histoplasmosis. The clinical presentations may be atypical, even mimicking acute bacterial sepsis. The diagnosis should be sought in any HIV-infected patient with an unexplained infection and residence or travel in an endemic area even in the remote past. Studies should include bone marrow examinations for histoplasmosis as well as skin biopsies with special strains and cultures for fungi for both infections. Sputum or bronchoscopy specimens have often been the source of a diagnosis in coccidioidomycosis. Serologic tests for antibody in both diseases yield inconsistently positive results in AIDS patients. Treatment of the acute infection should be with amphotericin B followed by maintenance suppressive therapy with ketoconazole or Amphotericin B.     

Prevalence and characteristics of nursing home-acquired infections in the aged.

OBJECTIVES: This study provides estimates of the prevalence of infections in all patients from a representative sample of 53 Maryland nursing homes; identifies risk factors for these infections; and describes diagnostic procedures carried out. METHODS: The records of 4,259 patients in a stratified random sample of 53 Maryland nursing homes were reviewed for diagnostic procedures, medical, functional, and behavioral status. Infections were identified by signs, symptoms, and laboratory findings. RESULTS: Study patients were characteristic of aged patients in US nursing homes. The prevalence of infections actually acquired in the nursing home (80% of all infections) was 4.4%. Multivariate analysis revealed that skin infections (35% of nursing home-acquired infections) were associated with skin ulcers and inversely with urine incontinence. Fevers of uncertain source (13%) were associated with bladder catheters. Symptomatic urinary infections (12%) and lower respiratory infections (12%) were associated with bedfast status, and the latter with tracheostomy and lung disease. Skin ulcers, urethral catheters, and bedfast status were markers for nursing home-acquired infection. The prevalence of infection in patients with all three markers was 32%; in patients with none, 2%. Fewer than a quarter of the four most common nursing home-acquired infections received an evaluation which met minimal diagnostic criteria established by a panel of infectious disease specialists and geriatricians. Patients with dementia, those in large homes (greater than 150 beds), and those in urban homes were less likely to be evaluated in a manner meeting these criteria. CONCLUSIONS: Use of three characteristics (ie skin ulcers, urethral catheters, bedfast status) to identify patients at risk for nursing home-acquired infections may allow targeted infection surveillance and prevention programs. In addition, nursing home-acquired infections are not evaluated uniformly across patients and facilities, suggesting the need to establish, through further study, guidelines for such evaluations.     

Fatal disseminated adenovirus infection in a renal transplant recipient.

A 61 year old woman died of diffuse interstitial adenovirus pneumonia 55 days after receiving a cadaveric renal allograft. The adenovirus was serologically distinct from the 33 known human adenovirus serotypes and appears to represent a new human adenovirus. Pathologic and virological findings indicate that the pneumonia was only one manifestation of a disseminated infection, the source of which may have been a latent adenovirus infection preexisting in the donor kidney. The establishment of the etiologic diagnosis in this case, which was complicated by the presence of oculocutaneous and esophageal herpes simplex virus infection as well as focal pulmonary aspergillosis, required coordinated histopathologic and virological investigation. Our findings demonstrate that severe viral infections in transplant recipients are not caused exclusively by members of the herpesvirus group.     

Clinical Infections and Bloodstream Isolates Associated with Fever in Patients Undergoing Chemotherapy for Acute Myeloid Leukemia

Summary Background: Patients with acute myeloid leukemia (AML) are at high risk for infections. The aim of this study was to identify the sources of fever and the type of pathogens that cause bloodstream infection in patients with AML undergoing cytotoxic chemotherapy and antibiotic prophylaxis. Patients and Methods: The source of fever and the type of pathogens causing bloodstream infection were identified for 129 febrile episodes experienced by 42 patients with AML receiving cytotoxic chemotherapy and antibiotic prophylaxis. Results: A source of fever was identified in 81% of all febrile episodes. Mucositis (21.7%), pneumonia (13.2%), central venous catheter infection (12.4%), neutrophenic enterocolitis (9.3%) and invasive fungal disease (9.3%) were the most common sources of fever. Of 16 central venous catheter infections, seven (43.8%) were not associated with local signs. 49 febrile episodes (37.9%) were associated with bloodstream infections, of which 14 (28.6%) were polymicrobic and seven (14.3%) had an undefined source of infection. Bloodstream infection was commonly associated with cellulitis (60%), mucositis (57.1%), central venous catheter infection (55.6%), neutropenic enterocolitis (41.7%) and invasive fungal disease (41.7%). Gram-positive microorganisms were the most common blood isolates (75.8%). Gram-negative bacteremic infections occurred in eight episodes (12.1%) experienced by patients who were nor receiving ciprofloxacin prophylaxes at the time of bacteremia. Noninfectious sources of fever accounted for 23 (17.8%) of the 129 febrile episodes. Conclusion: Although the spectrum of pathogens that cause infection in this group of patients has shifted from gram-negative to gram-positive bacteria, the most common sources of infection remain the same as previously described and they mainly involve integumental surfaces. Received: December 5, 1999 · Revision accepted: August 8, 2000     

Infections due to Lancefield group C streptococci

Our experience with group C streptococcal infection over the past 15 years demonstrates an important and emerging role for this hemolytic organism as an opportunistic and nosocomial pathogen. Significant risk factors in this predominantly male population included chronic cardiopulmonary disease, diabetes, malignancy, and alcoholism. Bacteremia occurred in 74% of cases seen in our series. Nosocomial acquisition of infection was observed in 26%, and infection was frequently polymicrobial in nature with gram-negative enteric bacilli isolated most commonly along with group C streptococci. We observed a broad spectrum of infections including puerperal sepsis, pleuropulmonary infections, skin and soft-tissue infection, central nervous system infection, endocarditis, urinary tract infection, and pharyngeal infections. Several cases of bacteremia of unknown source were observed in neutropenic patients with underlying leukemia. New syndromes of infection due to group C streptococci observed in our series included intra-abdominal abscess, epidural abscess, and dialysis-associated infection. Response to therapy and outcome was related to the underlying disease. While the literature suggests that patients with group C endocarditis respond better to synergistic penicillin-aminoglycoside regimens, patient numbers are too small to draw definite conclusions. The clinical significance of antibiotic tolerant group C streptococci remains uncertain. In patients with serious group C infections including endocarditis, meningitis, septic arthritis, or bacteremia in neutropenic hosts, we advocate the initial use of cell-wall-acting agents in combination with an aminoglycoside.     

Recurrent Listeria monocytogenes infection: relapse or reinfection with a unique strain confirmed by molecular subtyping.

We report a case of recurrent listeriosis for which molecular subtyping by automated ribotyping and pulsed-field gel electrophoresis confirmed either relapse of infection or reinfection due to a common source almost 9 months after initial infection due to a unique Listeria monocytogenes strain in a patient with colorectal cancer. This case report illustrates the potential use of molecular subtyping to further understand the pathogenesis and epidemiology of listeriosis and the potential for relapse of Listeria infections in humans.