Non-typhoidal salmonella bacteraemia--an under-recognized feature of AIDS in African adults

Non-typhoidal salmonella (NTS) infections are severe, invasive and recurrent in the HIV-infected adult, and NTS are the commonest cause of hospital admission with bacteraemia in sub-Saharan Africa. NTS bacteraemia typically presents in patients with HIV/AIDS once the CD4 count falls below 200 cells/microL. In-patient mortality is 35%-60%, and is highest in patients with confusion or severe anaemia. Among survivors, 25%-45% may have single or multiple recurrences of NTS bacteraemia 1-6 months after the first illness, requiring retreatment. Diagnosis relies on blood culture, so in many areas this disease cannot be definitively diagnosed, and must be empirically treated. Treatment is guided by local antibiotic sensitivities; fluoroquinolones are particularly useful for initial treatment if there is multidrug reistance to other agents, and may result in lower recurrence rates than other agents. Where possible, long-term secondary chemoprophylaxis to prevent recurrence is advisable. Successful ARV treatment also prevents recurrence. There is inadequate knowledge about the epidemiology of carriage and transmission among at-risk populations.     

Bacteraemia and mortality among adult medical admissions in Malawi--predominance of non-typhi salmonellae and Streptococcus pneumoniae

OBJECTIVES: The high seroprevalence of HIV in Malawi might be expected to alter the pattern of pathogens isolated from bacteraemic patients. We aimed to describe the frequency and seasonal pattern of bacterial isolates from blood, their antibiotic susceptibility, and patient outcome, in order to provide data on which to base empirical antibiotic therapy and further studies of pathogenesis. METHODS: Over a 12-month period, blood cultures were taken from all febrile adult medical admissions to Queen Elizabeth Central Hospital, Blantyre. RESULTS: A total of 2789 out of 9298 adult general medical admissions had blood culture performed, of whom 449 (16.1%) grew significant pathogens. Non-typhi salmonellae (NTS) (37%) and Streptococcus pneumoniae (30%) were the two commonest isolates. Mortality was 18% among general medical admissions and 38% among bacteraemic patients. Mortality for individual pathogens was: NTS 33%; S. pneumoniae 36%; Escherichia coli 54%; Klebsiella spp. 58%; Neisseria meningitidis 44%; Salmonella typhi 17%. Despite an overwhelming association between the major pathogens and HIV infection (95% of S. pneumoniae cases and 92% of NTS cases were seropositive for HIV), a seasonal pattern was preserved. Streptococcus pneumoniae was more frequently isolated in the cold dry months, while STM isolates increased following a rise in temperature. A case of bacteraemia with Vibrio cholerae (serotype 01) was detected during a cholera outbreak in the rainy season. Although S. pneumoniae isolates were relatively susceptible to penicillin (88%) and chloramphenicol (74%), S. typhimurium isolates were fully susceptible only to chloramphenicol. CONCLUSIONS: This large study confirms the dominance of NTS and S. pneumoniae in bacteraemia in an area affected by HIV-1 and allows comparison of mortality by individual pathogens. It demonstrates a preserved seasonal pattern of bacteraemia for these major pathogens, despite an overwhelming association with HIV infection.     

Extraintestinal focal infections in adults with nontyphoid Salmonella bacteraemia: predisposing factors and clinical outcome

BACKGROUND: Nontyphoid Salmonella (NTS) isolates lead to not only self-limited, acute gastrointestinal infections, but also bacteraemia with or without extraintestinal focal infections (EFIs). The risk factors associated with EFIs in adults with NTS bacteraemia were not clearly elucidated. METHODS: In a medical center in southern Taiwan, patients aged > or = 18 years with NTS bacteraemia between January 1999 and June 2005 were included for analysis. RESULTS: Of 129 patients, 51 (39.5%) were complicated with EFIs. The most common EFI was mycotic aneurysm, followed by pleuropulmonary infections and spinal osteomyelitis. Compared to patients with primary bacteraemia, those with EFIs had higher leucocyte counts (P = 0.004) and higher serum levels of C-reactive protein (P < 0.0001). The development of EFIs was associated with a higher mortality, more severe septic manifestations, longer hospital stays and duration of antimicrobial therapy. Univariate analysis revealed that diabetes mellitus (P = 0.02), hypertension (P = 0.02) and chronic lung disease (P = 0.006) were significantly associated with EFIs. However, patients with malignancy (P = 0.01) and immunosuppressive therapy (P = 0.03) were less likely to develop EFIs. On the basis of multivariate analysis, an independent factor for the occurrence of EFIs was age [adjusted odds ratio (aOR) 1.05; 95% confidence interval (CI) 1.02-1.07; P < 0.0001], whilst malignancy was negatively associated with EFIs (aOR 0.16; 95% CI 0.14-0.78; P = 0.01). CONCLUSION: Amongst patients with NTS bacteraemia, EFIs often occurred in the aged, and were associated with a higher mortality and morbidity. Recognition of specific host factors is essential for identification of EFIs which often demand early surgical interventions and prolonged antimicrobial therapy.     

Risk factors for recurrent bleeding and mortality in human immunodeficiency virus–infected patients with acute lower GI hemorrhage

BACKGROUND: Little is known about lower gastrointestinal (GI) hemorrhage in the human immunodeficiency virus (HIV) infected population. Our aim was to determine the underlying causes, the clinical outcome, and the risk factors for recurrent bleeding and mortality in HIV-infected patients with acute LGIH. METHODS: We reviewed the medical records of consecutive HIV-infected patients with acute lower GI hemorrhage who were evaluated with endoscopy from January 1992 through January 1997 at Bellevue Hospital Center. RESULTS: During the 5-year study period, 312 patients with acute lower GI hemorrhage underwent colonoscopy (n = 233) or flexible sigmoidoscopy (n = 79). Cytomegalovirus colitis (25.3%), lymphoma (12.2%), and idiopathic colitis (12.2%) were the most common causes identified. Within 30 days of presentation, recurrent bleeding occurred in 17.6% of patients. Independent predictors of recurrent bleeding included the presence of at least one comorbid illness, a hemoglobin level of less than 8 gm/dL, a platelet count of less than 100,000/mm3, and major stigmata of hemorrhage. The 30-day mortality from lower GI hemorrhage was 14.4%, and the presence of comorbid disease, recurrence of bleeding, and surgical intervention were found to be the only independent predictors of mortality in this patient population. CONCLUSIONS: Acute lower GI hemorrhage in HIV-infected patients is most commonly caused by cytomegalovirus colitis and is associated with a high short-term morbidity and mortality.     

Salmonella infections in immunocompromised adults

Clinical syndromes caused by Salmonella infection in humans are divided into typhoid fever, caused by Salmonella typhi and Salmonella paratyphi, and a range of clinical syndromes, including diarrhoeal disease, caused by a large number of non-typhoidal salmonella serovars (NTS). Typhoid is a human-restricted and highly adapted invasive disease, but shows little association with immunocompromise. In contrast, NTS have a broad vertebrate host range, epidemiology that often involves food animals, and have a dramatically more severe and invasive presentation in immunocompromised adults, in particular in the context of HIV. Immunocompromise among adults, including underlying severe or progressive disease, chronic granulomatous disease, defects or blockade of specific cytokines (particularly IL-12/IL-23/IL-17 and TNF), and HIV, is associated with suppurative foci and with primary bacteraemic disease, which may be recurrent. These patients have markedly increased mortality. Worldwide, invasive recurrent NTS bacteraemia associated with advanced HIV disease is a huge problem, and the epidemiology in this context may be more human-restricted than in other settings. This review will describe the presentation and pathogenesis of NTS in different categories of immunocompromised adults, contrasted to typhoid fever.     

Severe malaria and concomitant bacteraemia in children admitted to a rural Mozambican hospital

Objectives  To describe the prevalence, aetiology and prognostic implications of coexisting invasive bacterial disease in children admitted with severe malaria in a rural Mozambican Hospital.
Methods  Retrospective study of data systematically collected from June 2003 to May 2007 in a rural Mozambican hospital, from all children younger than 5 years admitted with severe malaria.
Results  Seven thousand and forty-three children were admitted with a diagnosis of malaria. 25.2% fulfilled the criteria for severe malaria. 5.4% of the children with severe malaria and valid blood culture results had a concomitant bacteraemia. Case fatality rates of severe malaria cases rose steeply when bacteraemia was also present (from 4.0% to 22.0%, P  < 0.0001), and bacteraemia was an independent risk factor for death among severe malaria patients (adjusted OR 6.2, 95% CI 2.8–13.7, P  = 0.0001). Streptococcus pneumoniae , Gram-negative bacteria, Staphilococcus aureus and non-typhoid Salmonella (NTS) were the most frequently isolated microorganisms among severe malaria cases. Their frequency and associated case fatality rates (CFR) varied according to age and to syndromic presentation. Streptococcus pneumoniae had a relatively low CFR, but was consistently associated with severe malaria syndromes, or anaemia severity groups. No clear-cut relationship between malarial anaemia and NTS bacteraemia was found.
Conclusions  The coexistence of malaria and invasive bacterial infections is a frequent and life-threatening condition in many endemic African settings. In Mozambique, S. pneumoniae is the leading pathogen in this interaction, possibly as a consequence of the high HIV prevalence in the area. Measures directed at reducing the burden of both those infections are urgently needed to reduce child mortality in Africa.     

Recurrent acute pancreatitis and its relative factors

AIM: To evaluate the causes and the relative factors of recurrent acute pancreatitis. METHODS: From 1997 to 2000, acute pancreatitis relapsed in 77 of 245 acute pancreatitis patients. By reviewing the clinical treatment results and the follow-up data, we analyzed the recurrent factors of acute pancreatitis using univariate analysis and multivariate analysis. RESULTS: Of the 245 acute pancreatitis patients, 77 were patients with recurrent acute pancreatitis. Of them, 56 patients relapsed two times, 19 relapsed three times, each patient relapsed three and four times. Forty-seven patients relapsed in hospital and the other 30 patients relapsed after discharge. Eighteen patients relapsed in 1 year, eight relapsed in 1-3 years, and four relapsed after 3 years. There were 48 cases of biliary pancreatitis, 3 of alcohol pancreatitis, 5 of hyperlipidemia pancreatitis, 21 of idiopathic pancreatitis. Univariate analysis showed that the patients with local complications of pancreas, obstructive jaundice and hepatic function injury were easy to recur during the treatment period of acute pancreatitis (P= 0.022<0.05, P= 0.012<0.05 and P= 0.002<0.05, respectively). Multivariate analysis showed that there was no single factor related to recurrence. Of the 47 patients who had recurrence in hospital, 16 had recurrence in a fast period, 31 after refeeding. CONCLUSION: Acute pancreatitis is easy to recur even during treatment. The factors such as changes of pancreas structure and uncontrolled systemic inflammatory reaction are responsible for the recurrence of acute pancreatitis. Early refeeding increases the recurrence of acute pancreatitis. Defining the etiology is essential for reducing the recurrence of acute pancreatitis.     

Molecular investigation of recurrent tuberculosis in patients from Rwanda.

SETTING: Pulmonary tuberculosis (TB) patients enrolled in four provinces of Rwanda. OBJECTIVE: To determine the cause of recurrent TB. DESIGN: Serial Mycobacterium tuberculosis isolates obtained from patients with recurrent TB from January 2002 to September 2005 were genotyped by spoligotyping and mycobacterial interspersed repetitive unit-variable number of tandem repeat (MIRU-VNTR) typing. Drug resistance was determined by phenotypic susceptibility testing and sequencing of rpoB, katG, inhA and embB genes. RESULTS: Among 710 culture-positive TB patients enrolled in the study, initial drug susceptibility testing results were available for 638. Sixty-nine of these had multidrug-resistant (MDR) TB and 569 were non-MDR-TB. Among the MDR-TB patients, 22 had follow-up isolates after cure (n = 12) or chronic infection (n = 10). The DNA patterns of sequential isolates from 4 of the 12 previously cured MDR-TB patients were different, indicating re-infection. DNA patterns of isolates from the remaining 8 previously cured and 10 chronic MDR-TB patients were identical, suggesting reactivation and treatment failure, respectively. Among the non-MDR-TB patients, disease recurrence was observed in one case; this was determined to be due to reactivation after initial mixed infection. CONCLUSION: These results document a high treatment failure/reactivation rate for MDR-TB and suggest that re-infection within 2 years may not be a common cause of recurrent TB in this setting.     

Gram-negative bacteraemia (GNB) after 428 unrelated donor bone marrow transplants (UD-BMT): risk factors, prophylaxis, therapy and outcome

Gram-negative infection is an important cause of morbidity and mortality after unrelated donor-bone marrow transplantation (UD-BMT). We performed a retrospective case-control study to examine the risk factors, prophylaxis, therapy and outcome of Gram-negative bacteraemia (GNB) in 428 patients undergoing UD-BMT. The incidence of GNB was 3.6% in children and 19% in adults. Of the adults, 11% developed GNB >60 days post UD-BMT. Predisposing risk factors for GNB included 'high-risk' disease status, chronic graft-versus-host disease and use of systemic steroids. Fever, a raised C-reactive protein (CRP) and hypotension were common findings at presentation. Patients were routinely given prophylactic ciprofloxacin: resistance to this antibiotic was seen in 33% of isolates. We identified an age-matched control group undergoing UD-BMT over the same time period as the study group. Gram-positive bacteraemia was significantly more common in cases than controls. Mortality from GNB was 17% in children and 24% in adults. We conclude that GNB is a common complication of UD-BMT with a high associated mortality. Patients should be educated further to present rapidly with symptoms suggestive of infection.     

Pneumococcal disease in HIV-infected Malawian adults: acute mortality and long-term survival

OBJECTIVE: HIV-infected patients in Africa are vulnerable to severe recurrent infection with Streptococcus pneumoniae, but no effective preventive strategy has been developed. We set out to determine which factors influence in-hospital mortality and long-term survival of Malawians with invasive pneumococcal disease. DESIGN, SETTING AND PATIENTS: Acute clinical features, inpatient mortality and long-term survival were described among consecutively admitted hospital patients with S. pneumoniae in the blood or cerebrospinal fluid. Factors associated with inpatient mortality were determined, and patients surviving to discharge were followed to determine their long-term outcome. RESULTS: A total of 217 patients with pneumococcal disease were studied over an 18-month period. Among these, 158 out of 167 consenting to testing (95%) were HIV positive. Inpatient mortality was 65% for pneumococcal meningitis (n = 64), 20% for pneumococcaemic pneumonia (n = 92), 26% for patients with pneumococcaemia without localizing signs (n = 43), and 76% in patients with probable meningitis (n = 17). Lowered consciousness level, hypotension, and age exceeding 55 years at presentation were associated with inpatient death, but not long-term outcome in survivors. Hospital survivors were followed for a median of 414 days; 39% died in the community during the study period. Outpatient death was associated with multilobar chest signs, oral candidiasis, and severe anaemia as an inpatient. CONCLUSION: Most patients with pneumococcal disease in Malawi have HIV co-infection. They have severe disease with a high mortality rate. At discharge, all HIV-infected adults have a poor prognosis but patients with multilobar chest signs or anaemia are at particular risk.     

Cryptococcal infection in a cohort of HIV-1-infected Ugandan adults

OBJECTIVE: Despite the recognition of Cryptococcus neoformans as a major cause of meningitis in HIV-infected adults in sub-Saharan Africa, little is known about the relative importance of this potentially preventable infection as a cause of mortality and suffering in HIV-infected adults in this region. DESIGN: A cohort study of 1372 HIV-1-infected adults, enrolled and followed up between October 1995 and January 1999 at two community clinics in Entebbe, Uganda. METHODS: Systematic and standardized assessment of illness episodes to describe cryptococcal disease and death rates. RESULTS: Cryptococcal disease was diagnosed in 77 individuals (rate 40.4/1000 person-years) and was associated with 17% of all deaths (77 out of 444) in the cohort. Risk of infection was strongly associated with CD4 T cell counts < 200 x 10(6) cells/l(75 patients) and World Health Organization (WHO) clinical stage 3 and 4 (68 patients). Meningism was present infrequently on presentation (18%). Clinical findings had limited discriminatory diagnostic value. Serum cryptococcal antigen testing was the most sensitive and robust diagnostic test. Cryptococcal antigenaemia preceded symptoms by a median of 22 days (> 100 days in 11% of patients). Survival following diagnosis was poor (median survival 26 days; range 0-138). CONCLUSIONS: Cryptococcal infection is an important contributor to mortality and suffering in HIV-infected Ugandans. Improvements in access to effective therapy of established disease are necessary. In addition, prevention strategies, in particular chemoprophylaxis, should be evaluated while awaiting the outcome of initiatives to make antiretroviral therapy more widely available.     

Recurrent pneumococcal bacteremia: risk factors and outcomes

BACKGROUND: Recurrent pneumococcal bacteremia receives infrequent mention in the literature, usually in association with patients who are immunocompromised. OBJECTIVE: To examine recurrent cases of pneumococcal bacteremia to determine risk factors and outcomes (mortality rates and emergence of resistance) associated with recurrences. METHODS: We retrospectively reviewed all cases of pneumococcal bacteremia identified by our microbiology laboratory from January 1, 1992, through December 31, 1996. Demographic, clinical, and laboratory data were abstracted. RESULTS: There were 462 bacteremic episodes in 432 patients; 23 of these patients had 30 recurrent episodes. The 5.3% recurrence rate (23/432) is greater than that previously described. The median time to recurrence was 200 days. The mean age of patients with recurrences was 34 years, 70% were women, all were black or Hispanic (in near equal numbers), and 87% were infected with the human immunodeficiency virus (HIV). Human immunodeficiency virus infection, coexistent cancer, and female sex were independent predictors of recurrence. Only patients who were HIV-infected had multiple recurrences. Isolates from recurrent bacteremias were more likely to be penicillin-resistant than were initial bacteremic isolates (relative risk, 2.0; P =.16). Patients with recurrences had a higher (although not statistically significant) mortality rate than those without recurrences (22% vs 16%; P =.33). There was an inverse relationship between severity of illness and likelihood of recurrence. CONCLUSIONS: Rates of recurrent pneumococcal bacteremia may be higher than previously reported. In patients with recurrent pneumococcal bacteremia, the presence of an underlying immunodeficiency should be investigated.     

Relapse rates after short-course (6-month) treatment of tuberculosis in HIV-infected and uninfected persons.

OBJECTIVE: To determine the rate of tuberculosis relapse among HIV-seropositive and -seronegative persons treated for active tuberculosis with short-course (6-month) therapy. DESIGN: Consecutive cohort study. SETTING: City of Baltimore tuberculosis clinic. PATIENTS: Tuberculosis patients treated between 1 January 1993 and 31 December 1996. INTERVENTION: Patients received 2 months of isoniazid, rifampin, pyrazinamide and ethambutol followed by 4 months of isoniazid and rifampin. MAIN OUTCOME MEASURE: Passive follow-up for tuberculosis relapse was performed through September 30, 1998. RESULTS: There were 423 cases of tuberculosis during the study period; 280 patients completed a 6-month course of therapy. Therapy was directly-observed for 94% of patients. Of those who completed therapy, 47 (17%) were HIV-seropositive, 127 (45%) were HIV-seronegative, and 106 (38%) had unknown HIV status. HIV-infected patients required more time to complete therapy (median 225 versus 205 days; P = 0.04) but converted sputum culture to negative within the same time period (median 77 versus 72 days; P = 0.43) as HIV-seronegative or unknown patients. Relapse occurred in three out of 47 (6.4%) HIV-infected patients compared to seven out of 127 (5.5%) HIV-seronegative patients (P = 1.0). Relapse rates also did not differ when HIV-seropositive patients were compared with HIV-seronegative and patients with unknown HIV status (6.4% versus 3.0%; P = 0.38). Of the 10 patients with tuberculosis relapse, restriction fragment length polymorphism data were available for five; all five relapse isolates matched the initial isolate. CONCLUSIONS: These results support current recommendations to treat tuberculosis in HIV-infected patients with short-course (6-month) therapy.     

Clinical features and therapeutic implications of 104 episodes of monomicrobial Aeromonas bacteraemia

OBJECTIVES: Aeromonas bacteraemia is not a common infectious disease, but can cause a grave outcome in infected cases. In this study, clinical presentations and prognostic factors of cases of monomicrobial Aeromonas bacteraemia were analysed. Also, the impact of beta-lactam and aminoglycoside in combination and of emerging cephalosporin-resistance during therapy was discussed. METHODS: From 1989 to 1998 in a medical centre in southern Taiwan, those cases with monomicrobial Aeromonas bacteraemia were included for study. RESULTS: A total of 104 episodes of monomicrobial Aeromonas bacteraemia, accounting for 74% of all Aeromonas bacteraemia, were encountered. The infections usually occurred in the patients with hepatic cirrhosis (54%) or malignancy (21%) and were community-acquired (74%). Cases of community-acquired bacteraemia were more likely to have cirrhosis, a high severity score at onset, and a worse prognosis than those of nosocomial bacteraemia did and nosocomial isolates were less susceptible to cefoxitin and cefotaxime. Forty-three percent of cases had a concomitant infection focus, such as primary peritonitis, invasive cellulitis or necrotizing fasciitis, biliary tract or burn wound infections. Crude fatality rate within 2 weeks after the onset was 30%. Secondary bacteraemia and a higher severity score ( > or = 4) for illness at the first presentation were independently associated with a fatal outcome. The therapeutic superiority of beta-lactam and aminoglycoside in combination cannot be demonstrated in patients with Aeromonas bacteraemia. Cefotaxime resistance emerged in 3.4% of 58 patients treated with a cephalosporin for at least 72 h. None of the community-acquired isolates, but one-quarter of the nosocomial isolates, were resistant to cefotaxime. CONCLUSIONS: Aeromonas bacteraemia usually occurred in patients with liver cirrhosis or malignancy, and heralded a poor prognosis, especially while associated with a relevant infectious source or with a higher severity score at presentation. The superiority of aminoglycoside and beta-lactam in combination cannot be demonstrated while treating those patients, and the emergence of antimicrobial resistance to cephalosporin was a rare event during cephalosporin therapy. Thus, a broad-spectrum cephalosporin remains one of the antimicrobial alternatives for invasive community-acquired Aeromonas infections.     

Recurrent invasive pneumococcal disease in individuals with human immunodeficiency virus infection

The proportion of relapses and reinfections that are potentially preventable by vaccine in human immunodeficiency virus (HIV)-infected persons with recurrent pneumococcal disease is unknown. Isolates from HIV-infected individuals from Baltimore with recurrent pneumococcal invasive disease were collected from 1 January 1995 through 31 December 2000. Serotyping and pulsed-field gel electrophoresis were performed. From 1 January 1995 through 31 December 1998, 14.9% (404/2717) of those who had a pneumococcal infection were HIV infected. The recurrence rate among HIV-infected individuals was 6.4-fold higher than that among individuals without HIV infection (P<.01). Among recurrent infections in 41 individuals, there were 42 reinfections and 6 relapses. All relapses and 91% (70/77) of reinfections were due to serotypes covered by the 23-valent pneumococcal polysaccharide vaccine. Reinfection was more common than relapse among HIV-infected individuals with recurrent pneumococcal disease. Although a substantial proportion of recurrent pneumococcal infections was potentially preventable by vaccine, creating an effective vaccine may be challenging for this population.     

Outcomes after endocarditis or device infection in patients with left ventricular epicardial leads versus coronary sinus leads

Background

There is scant data about outcomes in patients with left ventricular epicardial (LVE) leads who develop endocarditis or device-related infection.

Objective

This retrospective study evaluated mortality and recurrence of infection among patients with LVE leads in comparison to patients with endovascular coronary sinus (CS) leads after the development of endocarditis or device-related infection.

Methods

Patients with cardiac resynchronization therapy (CRT) devices who developed endocarditis or pocket infection over 5 years at Cleveland Clinic were included in the study. The groups were all patients with LVE leads versus CRT devices without epicardial leads that developed endocarditis or pocket infection. Mortality was assessed using the Social Security Death Index and re-infection was assessed by reviews of the medical record.

Results

Prospective extraction of the CRT device and leads occurred among all 50 patients with CS leads and 8 of the 14 patients with LVE leads. The survival rate was 92.9 versus 92 % and freedom from re-infection rate was 64.3 versus 80 % in the patients with LVE leads versus CS leads, respectively, over 1 year (P value?=?0.918 and 0.226, respectively). At 3 years, the survival rate in LVE lead group was 92.9 % and freedom from re-infection rate was 64.3 % in comparison to survival rate of 90 % and freedom from re-infection rate of 68 % in the CS group (P value?=?0.751 and 0.798, respectively).

Conclusion

After development of endocarditis or pocket infection, no statistically significant differences were seen in mortality, or recurrent infection between patients with LVE leads and those with CS leads.     

Recurrent Listeria monocytogenes bacteraemia in a liver transplant patient

Summary We report a case of a recurrentListeria monocytogenes bacteraemia in a 46 year-old liver transplant patient. Serotyping revealed that the two episodes of bacteraemia were caused by different strains. The possibility of a recrudescence of a persisting infection was rejected. We concluded that the recurrent bacteraemia in this predisposed patient was due to re-infection, and that antibiotic treatment (amoxicillin plus an aminoglycoside) resulted in a complete eradication of the infective microorganism. Therefore long-term suppressive antibiotic treatment was not indicated. The source of theseL. monocytogenes infections was not found.

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Rezidivierende Listeria monocytogenes-Bakteriämie bei einer Lebertransplantat-Empfängerin

Zusammenfassung Wir berichten über eine rezidivierendeListeria monocytogenes-Bakteriämie bei einer 46 Jahre alten Lebertransplantat-Empfängerin. Durch Serotypisierung wurde festgestellt, daß die beiden Bakteriämien durch verschiedene Stämme ausgelöst wurden. Die Möglichkeit einer wiederaufflackernden persistierenden Infektion wurde ausgeschlossen. Wir gehen davon aus, daß die rezidivierende Bakteriämie bei dieser prädisponierten Patientin durch Reinfektion verursacht wurde und daß die Antibiotikatherapie (Ampicillin plus Aminoglykosid) den Infektionserreger vollständig eliminiert hatte. Es bestand folglich keine Indikation für eine Antibiotika-Langzeit-Suppressionstherapie. Die Infektionsquelle für dieseL.-monocytogenes-Infektionen wurde nicht gefunden.

     

Factors contributing to anaemia after uncomplicated Plasmodiumfalciparum malaria in children

The factors contributing to anaemia in falciparum malaria were characterized in 1261 prospectively studied children in an endemic area of southwestern Nigeria. Of these, 487 (39%) presented with anaemia (haematocrit <30%). The following were found to be independent risk factors for anaemia at presentation: age <5 years, history of illness >3 days before presentation, presence of fever, a palpable liver, >parasitaemia 10,000/μl blood, and gametocytaemia. The mean maximum fractional fall in haematocrit (FFH) after treatment was 13.8% (95% confidence interval [CI] 13-14.6) of the baseline value. This occurred 3 days after treatment began and correlated positively with enrolment haematocrit. In children whose haematocrit was >30% at enrolment, the following were found to be independent risk factors associated with subsequent development of anaemia during follow-up: age <5 years and parasitaemia ≥100,000 parasites/μl. Haematological recovery was usually complete by 4-5 weeks, but was slower in children who were anaemic at enrolment and in those with recrudescence of their infections. Half of the children with recrudescence were still anaemic at 4 weeks. These findings have implications for the control of the burden of malarial anaemia in children in sub-Saharan African countries.     

Recurrent tuberculosis in Houston, Texas: a population-based study.

OBJECTIVE: To determine the predictors of recurrence of tuberculosis (TB), the drug resistance pattern of Mycobacterium tuberculosis strains recovered from recurrent TB patients, and the frequency of re-infection with a new M. tuberculosis strain among patients with recurrent disease. DESIGN: A population-based, retrospective case-control study using the Houston Tuberculosis Initiative database. RESULTS: We found that, among 100 patients with recurrent TB who completed adequate therapy for a first episode of TB, not receiving directly observed therapy, pulmonary disease, HIV/AIDS diagnosis, not having a family physician, being unemployed and using public transportation were predictors of recurrent disease. There was a significant increase in drug-resistant M. tuberculosis strains in the second episode of disease compared to the first episode (21.3% vs. 8.2%, P = 0.04). Exogenous re-infection with a new strain of M. tuberculosis was found to cause 24-31% of recurrent TB. CONCLUSION: Recurrent TB in Houston is associated with a significant increase in drug-resistant M. tuberculosis strains. Re-infection with a new M. tuberculosis strain causes a significant proportion of recurrent TB in an area of low TB incidence. Patients with HIV/AIDS constitute a population at increased risk of disease recurrence.