Capnocytophaga species: infections in nonimmunocompromised and immunocompromised hosts

Retrospective review of isolates of Capnocytophaga, a genus of capnophilic gram-negative bacilli, referred to the Massachusetts State Laboratory Institute in Boston revealed 31 patients with infection due to Capnocytophaga, 16 in nonimmunocompromised hosts. These infections included empyema (three patients), lung abscess (one), sinusitis (one), conjunctivitis (three), subphrenic abscess (one), wound (three), osteomyelitis (one), and bacteremia (three). Two of the wound infections were closed-fist injuries involving bone or soft tissue. Capnocytophaga was frequently isolated as part of a polymicrobial infection with other oral flora. There was only one death in the nonimmunocompromised group. In contrast, of 15 immunocompromised patients with 16 episodes of bacteremia due to Capnocytophaga, 87% had leukopenia and 73% had significant oral pathology such as gingivitis, mucositis, or ulceration. Five immunocompromised patients died. Thus, Capnocytophaga species may cause disease in both nonimmunocompromised and immunocompromised hosts. Isolation of this organism should suggest an oral source for infection.     

Risk factors for mortality caused by nontyphoidal Salmonella sp. in children.

OBJECTIVE: To identify the risk factors for mortality in extraintestinal nontyphoidal Salmonella (NTS) infections in infants and children. METHODS: We performed a retrospective analysis of 107 patients with at least one nonfecal culture for NTS seen from January 1988 to December 1995. RESULTS: The median age was 12 (range 1-216) months. Malnutrition was found in 55 patients (51%), and 22 (20%) displayed severe features (weight loss >40%). Seventy-two patients (67%) had previously been hospitalized, and 59 (55%) had received antibiotics during the month before admission. Fever (85%) and diarrhea (56%) were the most frequent clinical manifestations. Nineteen children (18%) had leukopenia. Forty-nine patients (46%) had only bacteremia, 33 (31%) bacteremia with focal infections, and 25 (23%) focal infections with negative blood cultures. Forty-seven strains (44%) were multiresistant, and 40 of them were nosocomially acquired. Eight patients (7%) had received inappropriate antibiotic treatment, and two of them died. Thirteen (12%) children died. Age, underlying disease, previous admission, previous antibiotic therapy, type of infection, susceptibility of the strains and inappropriate antibiotic treatment were not statistically significant risk factors for mortality. A logistic regression analysis selected the following variables as independently influencing outcome: malnutrition (P<0.01), leukopenia (P<0.002) and presence of diarrhea (P<0.02). CONCLUSIONS: Children with extraintestinal infections by NTS with leukopenia, malnutrition and presence of diarrhea have a higher risk of death.     

Invasive non-typhoidal salmonellosis in immunocompetent infants and children.

OBJECTIVE: To investigate the extraintestinal manifestations of non-typhoidal Salmonellae (NTS) infection in immunocompetent infants and children. METHOD: The study took place at the University General Hospital at Heraklion, Crete. Over a 10-year period from 1993-2002 we studied 1087 patients, of whom 443 were children less than 14 years old, with a culture-proven diagnosis of NTS infection. Stool and blood cultures were routinely obtained in patients presenting with fever and diarrhea. The cases of invasive infection in otherwise well children, including bacteremia and/or extraintestinal focal infections were further analyzed. RESULTS: Invasive cases were less common in children than adults (4.06% vs. 8.7%; relative risk 0.467; 95% confidence intervals (CI) 0.279-0.784; p=0.0033). Furthermore, invasive cases were much less common in the otherwise well than in immunocompromised children (3.5% vs. 21.4%; relative risk 0.163; 95% CI 0.053-0.500; p=0.0008). The 15 otherwise well children with invasive NTS infection were aged from 3 weeks to 7.5 years, and nine were aged less than 12 months. Among them, 11 presented with bacteremia, and four with focal extraintestinal infections (rectal abscess, deep neck abscess, urinary tract infection, elbow arthritis). Salmonella enterica subsp. enterica serovars Enteritidis and Virchow were the most common invasive serotypes. All invasive strains were susceptible to beta-lactams including ampicillin, and to cotrimoxazole. All patients made a complete recovery with intravenous antibiotics and did not present with relapses or major infections during long-term follow-up. CONCLUSION: Invasive non-typhoidal salmonellosis in immunocompetent children is less frequent than in both immunocompromised children and in adulthood. However, invasive cases may well occur in otherwise healthy children, especially during infancy. In these patients, prompt appropriate treatment leads to favorable outcomes.     

Community-acquired infections in type 2 diabetic patients and their nondiabetic partners. The Fremantle Diabetes Study

AIMS: The aim of this study was to investigate the association between Type 2 diabetes and community-acquired infections. METHODS: We recruited 68 patients (mean+/-S.D. age=64.9+/-9.1 years; 57.4% males) from a community-based cohort and their nondiabetic partners (age=63.8+/-9.9 years; mean relationship duration=37.3+/-11.5 years) to a prospective observational matched-pair cohort study. Participants were assessed for infection risk factors and were required to complete an infection diary over the following year. RESULTS: Sixty patient-partner pairs returned completed diaries. A greater proportion of patients than partners had received influenza vaccination in the past year (73.3% vs. 60.0%; P=.057), but pneumococcal vaccination coverage in the previous 5 years was similar (11.7% vs. 10.0%; P=1.0). The proportions of patients and partners reporting no infections were similar (51.7% vs. 58.3%; P=.52), but the diabetic patients were more likely to have experienced more than one infection (33.3% vs. 18.3%: P=.022). Baseline glycosylated hemoglobin levels in patients with and without at least one infection were similar, and there was no association between multiple infections and glycosylated hemoglobin (P>.2 in each case). After adjusting for age and gender, the probability of at least one infection during follow-up was not associated with diabetes (P=.33), but the number of infections was positively associated with diabetes (P=.005). CONCLUSION/INTERPRETATION: Although similar proportions of Type 2 diabetic patients and their nondiabetic partners remained infection-free over a 12-month period, the diabetic patients who developed infections had a greater number of episodes. Glycemic control did not predict the risk or frequency of community-acquired infections in the diabetic group.     

Infections and functional impairment in nursing home residents: a reciprocal relationship

OBJECTIVES: To determine the relationship between infections and functional impairment in nursing home residents. DESIGN: Prospective cohort study (follow-up period, 6 months). SETTING: Thirty-nine nursing homes in western Switzerland. PARTICIPANTS: A total of 1,324 residents aged 65 and older (mean age 85.7; 76.6% female) who agreed to participate, or their proxies, by oral informed consent. MEASUREMENTS: Functional status measured every 3 months. Two different outcomes were used: (a) functional decline defined as death or decreased function at follow-up and (b) functional status score using a standardized measure. RESULTS: At the end of follow-up, mortality was 14.6%, not different for those with and without infection (16.2% vs 13.1%, P=.11). During both 3-month periods, subjects with infection had higher odds of functional decline, even after adjustment for baseline characteristics and occurrence of a new illness (adjusted odds ratio (AOR)=1.6, 95% confidence interval (CI)=1.2-2.2, P=.002, and AOR=1.5, 95% CI=1.1-2.0, P=.008, respectively). The odds of decline increased in a stepwise fashion in patients with zero, one, and two or more infections. The analyses predicting functional status score (restricted to subjects who survived) gave similar results. A survival analysis predicting time to first infection confirmed a stepwise greater likelihood of infection in subjects with moderate and severe impairment at baseline than in subjects with no or mild functional impairment at baseline. CONCLUSION: Infections appear to be both a cause and a consequence of functional impairment in nursing home residents. Further studies should be undertaken to investigate whether effective infection control programs can also contribute to preventing functional decline, an important component of these residents' quality of life.     

Natural T, gammadelta, and NK cells in mycobacterial, Salmonella, and human immunodeficiency virus infections

NK cells, gammadelta T cell antigen receptor chain-positive cells, and CD3(+)CD16/56(+) (natural T [NT]) cells are involved in innate immunity and immunoregulation; however, their role in clinical infection is not well defined. Cytofluorometric analysis was used to examine peripheral blood from bacteremic, nonbacteremic, and healthy human immunodeficiency virus (HIV)-positive and -negative persons in Malawi, Africa. Mycobacteremia was associated with a higher proportion of CD3(+)CD8(-) gammadelta cells (median, 16.6% vs. 0.7% for all other cells; P<.001), and Salmonella bacteremia was associated with a higher proportion of NT cells (4.3% vs. 2.2%; P=. 002). HIV plasma RNA levels were weakly positively correlated with NT cells (rs=.39; P=.002), NK cells (rs=.38; P=.003), and gammadelta cells (rs=.43; P<.001). Compared with patients who survived, patients who died had a higher percentage of NT cells (3.7% vs. 1. 9%; P=.017) and a higher percentage of NT cells that spontaneously produced interferon-gamma (2.4% vs. 1.2%; P=.035). The data support the clinical relevance of gammadelta and NT cells in mycobacterial, Salmonella, and HIV infections and of NT cells in mortality.     

Nontyphoid Salmonella bacteremia: age-related differences in clinical presentation, bacteriology, and outcome.

In a retrospective study, 80 episodes of nontyphoid salmonella (NTS) bacteremia in children were compared with 55 episodes in adults over a 10-year period. The study disclosed major differences in the predisposition, clinical presentation, and outcome as well as the microbiology of NTS bacteremia in relation to age. Adults were more likely than children to have predisposing diseases (95% vs. 15%, respectively; P < .0001) and to receive prior medications (95% vs. 23%, respectively; P < .0001), particularly immunosuppressive agents (58% vs. 5%, respectively; P < .0001). In most adults (67%), NTS infection presented as a primary bacteremia and was associated with a high incidence of extraintestinal organ involvement (34%) and a high mortality rate (33%). In children, NTS bacteremia was usually secondary to gastroenteritis (75%) and caused no fatalities. Although group D Salmonella (78%) and the serovar Salmonella enteritidis were the predominant isolates from adults, the emergence of infections due to group C Salmonella (46%) and the serovar Salmonella virchow in children was noted.     

Acute HIV infection among Kenyan infants.

BACKGROUND: Clinical signs and symptoms of acute human immunodeficiency virus (HIV) infection in infants are not well characterized. METHODS: Serial clinical assessments and HIV PCR assays were conducted in a cohort of children born to HIV-seropositive mothers from birth to 2 years of age. Acute HIV infection visits were defined as those up to 3 months prior to and including the visit at which HIV DNA was first detected. Noninfection visits included all visits at which the child had test results negative for HIV, including the last visit at which a test result negative for HIV DNA was obtained in children who later acquired HIV infection. Differences in the prevalence of symptoms at acute infection versus noninfection visits were determined overall and were stratified by age at infection (<2 months vs. >or=2 months). HIV RNA was measured serially in infected infants and was compared between infants with and infants without symptoms of acute HIV infection. RESULTS: There were 125 acute infection visits (among 56 infants) and 3491 noninfection visits (among 306 infants). Acute HIV infection was associated with rash (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.1-2.8), failure to thrive (OR, 1.9; 95% CI, 1.0-3.5), and lymphadenopathy (OR, 2.5; 95% CI, 1.4-4.8). Acute HIV infection was associated with lymphadenopathy (OR, 2.6; 95% CI, 1.3-5.0) in infants <2 months of age and with pneumonia (OR, 3.2; 95% CI, 1.1-9.3) and dehydration (OR, 6.0; 95% CI, 1.9-18.5) in infants >or=2 months of age. Infant peak viral load and mortality were not associated with symptoms of acute HIV infection. However, infants with symptoms had higher viral levels later in the course of infection than did those without symptoms (P=.05). CONCLUSIONS: Infants may manifest symptoms early during the course of HIV infection, and symptoms of acute HIV infection may correlate with poor viral control. Rash, failure to thrive, lymphadenopathy, pneumonia, and dehydration may signify acute HIV infection in infants.     

Antimicrobial-resistant nontyphoidal Salmonella is associated with excess bloodstream infections and hospitalizations

BACKGROUND: Nontyphoidal Salmonella is a leading cause of foodborne illness. Few studies have explored the health consequences of antimicrobial-resistant Salmonella. METHODS: The National Antimicrobial Resistance Monitoring System (NARMS) performs susceptibility testing on nontyphoidal Salmonella isolates. The Foodborne Diseases Active Surveillance Network (FoodNet) ascertains outcomes for patients with culture-confirmed Salmonella infection, in 9 states, each of which participates in NARMS. We analyzed the frequency of bloodstream infection and hospitalization among patients with resistant infections. Isolates defined as resistant to a clinically important agent were resistant to 1 or more of the following agents: ampicillin, ceftriaxone, ciprofloxacin, gentamicin, and/or trimethoprim-sulfamethoxazole. RESULTS: During 1996-2001, NARMS received 7370 serotyped, nontyphoidal Salmonella isolates from blood or stool. Bloodstream infection occurred more frequently among patients infected with an isolate resistant to > or =1 clinically important agent (adjusted odds ratio [OR], 1.6; 95% confidence interval [CI], 1.2-2.1), compared with patients with pansusceptible infection. During 1996-2001, FoodNet staff ascertained outcomes for 1415 patients who had isolates tested in NARMS. Hospitalization with bloodstream infection occurred more frequently among patients infected with an isolate resistant to > or =1 clinically important agent (adjusted OR, 3.1; 95% CI, 1.4-6.6), compared with patients with pansusceptible infection. CONCLUSIONS: Patients with antimicrobial-resistant nontyphoidal Salmonella infection were more likely to have bloodstream infection and to be hospitalized than were patients with pansusceptible infection. Mitigation of antimicrobial resistance in Salmonella will likely benefit human health.     

Association between surfactant protein A gene locus and severe respiratory syncytial virus infection in infants.

Respiratory syncytial virus (RSV) causes seasonal epidemics of bronchiolitis among susceptible infants. Surfactant protein A (SP-A), a lung C-type lectin involved in innate host defense, opsonizes RSV and enhances phagocytosis. The candidate gene approach was used to investigate association of SP-A polymorphism with susceptibility to severe RSV infection. Genotype analysis was done for 86 infants with severe RSV infection and 95 matched control subjects. A significant difference in the frequency of SP-A2 was observed. The SP-A2 allele 1A(3) was overrepresented in RSV-infected infants, compared with control subjects (5% vs. 0.5%; P =.006), whereas allele 1A was underrepresented (1% vs. 6%; P =.011). The allele pool in which lysine was amino acid 223 was overrepresented in infants with severe RSV infection (28% vs. 18%; P =.023), whereas the allele pool in which proline was amino acid 99 was underrepresented (5% vs. 16%; P =.001). These results indicate that a genetic association exists between SP-A gene locus and severe RSV infection.     

Pulmonary cryptococcosis in nonimmunocompromised patients

BACKGROUND: Cryptococcus neoformans can cause serious systemic infections requiring systemic antifungal therapy in immunocompromised hosts. However, isolated pulmonary cryptococcosis in nonimmunocompromised hosts has been reported to resolve spontaneously without treatment. STUDY OBJECTIVE:s: To determine the role of antifungal therapy in the management of isolated pulmonary cryptococcosis in nonimmunocompromised hosts. DESIGN: Retrospective study. SETTING: Tertiary care, referral medical center PATIENTS: Thirty-six nonimmunocompromised subjects with isolated pulmonary cryptococcosis who received diagnoses at the Mayo Clinic (Rochester, MN) from 1976 to 2001. INTERVENTIONS: None. Measurements and results: Of 42 nonimmunocompromised subjects with cryptococcal infections, 36 (86%) had isolated pulmonary cryptococcosis. The mean (+/- SD) age of these 36 patients was 61 +/- 15 years (range, 14 to 88 years), and the groups included 17 men (47%) and 19 women (53%). Twenty-four patients (67%) were symptomatic, and 12 patients (33%) were asymptomatic. The most common presenting symptoms were cough, dyspnea, and fever. Cultures of sputum and bronchial washings most commonly yielded the diagnosis. Cerebrospinal fluid examination was performed in 11 patients (31%) and was negative in all of them. Follow-up information was available on 25 patients (69%) with a median duration of 19 months (range, 1 to 330 months). Twenty-three of these patients (92%) had resolution of their disease (no treatment, 8 patients; surgical resection only, 6 patients; and antifungal therapy, 9 patients). The condition of the two remaining patients had improved. There was no documented treatment failure, relapse, dissemination, or death in any of these 25 patients. CONCLUSIONS: Our findings suggest that an initial period of observation without the administration of antifungal therapy is a reasonable option for nonimmunocompromised subjects with pulmonary cryptococcosis in the absence of systemic symptoms or evidence of dissemination, as well as after surgical resection for focal cryptococcal pneumonia.     

Age-dependent differences in IgG isotype and avidity induced by measles vaccine received during the first year of life

BACKGROUND: Measles remains an important cause of death worldwide, and vaccinating individuals at an earlier age could lead to better control of the disease. However, persistence of maternal antibody and young age affect the quantity of vaccine-induced neutralizing antibody and may also affect antibody quality. METHODS: Enzyme immunoassay was used to analyze measles virus-specific IgG levels, avidity maturation, and isotype changes, using serum samples from infants who received measles vaccine at 6 months of age and measles-mumps-rubella (MMR)-II at 12 months of age (n=26), measles vaccine at 9 months of age and measles-mumps-rubella (MMR)-II at 12 months of age (n=48), or only MMR-II at 12 months of age (n=27). RESULTS: The median IgG level was lower among infants with maternal antibody than among those without maternal antibody. Compared with median avidity indices for infants aged 12 months, median values were lower for 6-month-old infants with maternal antibody (P=.0001), 6-month-old infants without maternal antibody (P=.001), 9-month-old infants with maternal antibody (P=.03), and 9-month-old infants without maternal antibody (P=.006). The median IgG3 level was highest at 6 months of age. IgG1 was predominant at 12 months. Low avidity responses at 6 or 9 months of age did not hinder higher avidity responses or the switch to IgG1 after secondary vaccination. The 2-dose regimen did not augment the response, compared with the response in infants who received 1 dose at 12 months of age. CONCLUSIONS: Avidity and isotype maturation of measles vaccine-induced antibody are affected by age, providing insight into the ontogeny of the immune response to measles vaccine.     

Bacteremia due to Stenotrophomonas maltophilia in patients with hematologic malignancies.

Predisposing factors, clinical characteristics, and antimicrobial treatment of 37 hematology patients with Stenotrophomonas maltophilia bacteremia who were seen at the department of hematology of the University La Sapienza (Rome) from 1987 to 1996 were evaluated. The results were compared with a control group of patients with Pseudomonas aeruginosa bacteremia. Profound neutropenia was more prolonged in the S. maltophilia group (P=.025), severe cellulitis occurred only in S. maltophilia-infected patients (11 [30%]; P=.0002), and the bacteremia presented as breakthrough infection in 56% of the cases due to S. maltophilia (vs. only 24% of those due to P. aeruginosa; P=.002). Acute mortality rates associated with S. maltophilia and P. aeruginosa bacteremia were 24% and 21%, respectively. In both groups, profound neutropenia and hypotension at the onset of bacteremia, duration of profound neutropenia during bacteremia, severity-of-illness score > or =4, and inappropriate antibacterial treatment were factors significantly associated with death. Most S. maltophilia isolates were resistant to aminoglycosides, beta-lactams, and ciprofloxacin. Cotrimoxazole and ticarcillin-clavulanic acid showed borderline activity. Prompt administration of in vitro-active antibiotics may improve the prognosis of S. maltophilia bacteremia, especially for immunocompromised patients, and novel drug combinations are needed for the treatment of severe infections.     

Human herpesvirus 8 infection and Kaposi's sarcoma among human immunodeficiency virus-infected and -uninfected women

Little is known about the epidemiology of human herpesvirus 8 (HHV-8) infections among women. A cross-sectional study was conducted of HHV-8 infection among human immunodeficiency virus (HIV)-infected and high-risk HIV-uninfected women. Serological tests with noninduced (latent) and induced (lytic) HHV-8 antigens were used to detect infection among 2483 participants of a multisite cohort. Reactivity to latent antigen was present in 4.1% and to induced antigens in 12.0% of women. Seven of 8 women who reported Kaposi's sarcoma had HHV-8 antibodies. Among HIV-positive women, HHV-8 infection was associated with use of crack, cocaine, or heroin (76% vs. 65%; P<.001), past syphilis (29% vs. 20%; P<.001), an injection drug-using male sex partner (61% vs. 53%; P=.014), black race (P=.010), and enrollment site (P=.015). In multivariate analysis, HIV infection, older age, past syphilis, black race, and enrollment site were independently associated with HHV-8 infection. In this cohort of North American women, HHV-8 infection was associated with HIV infection, drug use, and risky sexual behavior.     

Stimulation of lung growth in fetuses with lung hypoplasia leads to altered postnatal lung structure in sheep

Our objective was to describe the respiratory complications, clinical findings, and chest radiographic changes in the first year of life in infected and uninfected children born to HIV-1-infected women. We prospectively followed a cohort of 600 infants born to HIV-1-infected women from birth to 12 months in a multicenter study. Of these, 93 infants (15.5%) were HIV-1-infected, 463 were uninfected, and 44 were of unknown status prior to death or loss to follow-up. The cumulative incidence ( +/- SE) of an initial pneumonia episode at 12 months was 24.1 +/- 4.7% in HIV-1-infected children compared to 1.4 +/- 0.6% in HIV-1-uninfected children (P < 0.001). The rate of Pneumocystis carinii pneumonia (PCP) was 9.5 per 100 child-years. The HIV-1 RNA load was not higher in the group that developed pneumonia in the first year vs. those who did not. Children who developed lower respiratory tract infections or PCP had increased rates of decline of CD4 cell counts during the first 6 months of life. Lower maternal CD4 cell counts were associated with higher rates of pneumonia, and upper and lower respiratory tract infections. The rates of upper respiratory tract infection and bronchiolitis/reactive airway disease in infected children were not significantly different than in uninfected children. At 12 months, significantly more HIV-1-infected than uninfected children had tachypnea and chest radiographs with nodular and reticular densities. There was no relationship between cytomegalovirus infection in the first year of life and radiographic changes or occurrences of pneumonia. In conclusion, despite a low incidence of PCP, rates of pneumonia remain high in HIV-infected children in the first year of life. The incidence of pneumonia in uninfected infants born to HIV-1-infected mothers is low. Chest X-ray abnormalities and tachypnea suggest that subacute disease is present in infected infants. Further follow-up is warranted to determine its nature.     

Estimating Haemophilus influenzae type b vaccine effectiveness in England and Wales by use of the screening method

In October 1992, Haemophilus influenzae type b (Hib) conjugate vaccine was introduced to infants in the United Kingdom with a "catch-up" program for those aged <4 years. Initially, the rate of invasive Hib disease decreased dramatically but has been increasing since 1999. To determine possible reasons for this increase, the effectiveness of Hib conjugate vaccine was estimated by use of the screening method. Between October 1993 and December 2001, a total of 443 cases of Hib infection occurred in children eligible for vaccination; 363 (82%) were fully vaccinated. Vaccine effectiveness was estimated to be 56.7% (95% confidence interval, 42.5-67.4). Effectiveness was lower in children vaccinated during infancy, compared with those who were vaccinated during the catch-up campaign (P=.0033), declined with time since vaccination (P=.0008), and was lower in children born during 2000-2002, compared with other children scheduled for infant vaccination (P=.0041). Use of a catch-up vaccination program enhanced the control of Hib infection in England and Wales. Since 1999, however, low effectiveness in infants, declining effectiveness with age, and the use of lower-efficacy vaccines have contributed to increased rates of Hib infection. The potential role of boosters needs to be considered.     

Association of primary Pneumocystis carinii infection and sudden infant death syndrome.

To delineate clinical and histological features of the first Pneumocystis carinii infection affecting the immunocompetent host, P. carinii-specific histological stains were performed on autopsy lung specimens from 534 consecutive pediatric patients (those with AIDS and malignancies were excluded) in Santiago, Chile. P. carinii clusters were found in 4 (25%) of 16 infants who died of no apparent cause at arrival to the emergency department, and in 10 (2.9%) of 342 infants who died of multiple conditions at the hospital (P=.002, Fisher's exact test). This prompted us to analyze additional series of infants with sudden infant death syndrome (SIDS). In 161 additional SIDS cases, 47 (35.1%) of 134 infants from Chile and 4 (14.8%) of 27 infants from Oxford, United Kingdom, were found to have P. carinii clusters in the lungs. The quantity of P. carinii cysts was small compared with the numbers seen in immunocompromised hosts with P. carinii pneumonitis. This study provides histological evidence that primary P. carinii infection is associated with SIDS.     

The influence of human immunodeficiency virus coinfection on chronic hepatitis C in injection drug users: a long-term retrospective cohort study.

In this study we analyzed the influence of human immunodeficiency virus (HIV) infection on the course of chronic hepatitis C through multivariate analysis including age, alcohol consumption, immune status, and hepatitis C virus (HCV)-related virologic factors. Eighty HIV-positive and 80 HIV-negative injection drug users included between 1980 and 1995 were matched according to age, gender, and duration of HCV infection and followed-up during 52 months. The progression to cirrhosis was the primary outcome measure. The impact of HIV on HCV-RNA load, histologic activity index, response to interferon therapy, and liver-related death was also considered. In HIV-positive patients, chronic hepatitis C was characterized by higher serum HCV-RNA levels (P =.012), higher total Knodell score (P =.011), and poorer sustained response to interferon therapy (P =.009). High serum HCV-RNA level was associated with low CD4-lymphocyte count (P =.001). Necroinflamatory score was higher in HIV-positive patients (P =.023) independently of the CD4-lymphocyte count, whereas increased fibrosis was related to decreased CD4-lymphocyte count (P =.011). The progression to cirrhosis was accelerated in HIV-positive patients with low CD4 cell count (RR = 4.06, P =.024) and in interferon-untreated patients (RR = 4.76, P =.001), independently of age at HCV infection (P =.001). Cirrhosis caused death in 5 HIV-positive patients. The risk of death related to cirrhosis was increased in heavy drinkers (RR = 10.8, P =.001) and in HIV-positive patients with CD4 cell count less than 200/mm(3) (RR = 11.9, P =.007). In this retrospective cohort study, HIV coinfection worsened the outcome of chronic hepatitis C, increasing both serum HCV-RNA level and liver damage and decreasing sustained response to interferon therapy. Age and alcohol were cofactors associated with cirrhosis and mortality. Interferon therapy had a protective effect against HCV-related cirrhosis no matter what the patient's HIV status was.     

Antimicrobial susceptibility of nontyphoidal Salmonella isolated from humans in Belgium

Human nontyphoidal Salmonella infections are the primary cause of foodborne disease in developed countries, resulting in considerable morbidity and occasionally death, especially in immunocompromised patients. Strains of Salmonella that are resistant to antimicrobial agents have become a world-wide health problem. Fluoroquinolones are drugs of choice for treatment of human invasive salmonellosis, and have been useful for the treatment of infections caused by multi-resistant strains. However, strains resistant to ciprofloxacin have been noted. A random sample of 378 Salmonella strains of human origin was collected during 1998. Their susceptibility to 11 antimicrobial agents was determined by the agar dilution method according to NCCLS standards. In total, 38 serotypes were represented of which S. Enteritidis (20.4%), S. Typhimurium (20.4%), S. Hadar (9.0%), S. Brandenburg (7.9%), S. Infantis (7.7%), and S. Virchow (5.3%) were the most common. All strains were susceptible to ceftriaxone and ciprofloxacin. For nalidixic acid the rate of resistance was 19.0%. Of the 72 strains resistant to nalidixic acid, 31 were S. Hadar, and thus 91.2% (31/34) of the S. Hadar isolates showed resistance to nalidixic acid. Most of the S. Hadar strains were also resistant to ampicillin, tetracycline and sulphamethoxazole, and an elevated MIC50 (0.25 microgram/ml) and MIC90 (1 microgram/ml) was observed for ciprofloxacin. The high rate of resistance to nalidixic acid can be a first step towards the development of resistance to ciprofloxacin.