Treatment of enteric fever (typhoid and paratyphoid fever) with cephalosporins

BACKGROUND

Typhoid and paratyphoid (enteric fever) are febrile bacterial illnesses common in many low- and middle-income countries. The World Health Organization (WHO) currently recommends treatment with azithromycin, ciprofloxacin, or ceftriaxone due to widespread resistance to older, first-line antimicrobials. Resistance patterns vary in different locations and are changing over time. Fluoroquinolone resistance in South Asia often precludes the use of ciprofloxacin. Extensively drug-resistant strains of enteric fever have emerged in Pakistan. In some areas of the world, susceptibility to old first-line antimicrobials, such as chloramphenicol, has re-appeared. A Cochrane Review of the use of fluoroquinolones and azithromycin in the treatment of enteric fever has previously been undertaken, but the use of cephalosporins has not been systematically investigated and the optimal choice of drug and duration of treatment are uncertain.

OBJECTIVES

To evaluate the effectiveness of cephalosporins for treating enteric fever in children and adults compared to other antimicrobials.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL, MEDLINE, Embase, LILACS, the WHO ICTRP and ClinicalTrials.gov up to 24 November 2021. We also searched reference lists of included trials, contacted researchers working in the field, and contacted relevant organizations.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in adults and children with enteric fever that compared a cephalosporin to another antimicrobial, a different cephalosporin, or a different treatment duration of the intervention cephalosporin. Enteric fever was diagnosed on the basis of blood culture, bone marrow culture, or molecular tests.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were clinical failure, microbiological failure and relapse. Our secondary outcomes were time to defervescence, duration of hospital admission, convalescent faecal carriage, and adverse effects. We used the GRADE approach to assess certainty of evidence for each outcome.

MAIN RESULTS

We included 27 RCTs with 2231 total participants published between 1986 and 2016 across Africa, Asia, Europe, the Middle East and the Caribbean, with comparisons between cephalosporins and other antimicrobials used for the treatment of enteric fever in children and adults. The main comparisons are between antimicrobials in most common clinical use, namely cephalosporins compared to a fluoroquinolone and cephalosporins compared to azithromycin. Cephalosporin (cefixime) versus fluoroquinolones Clinical failure, microbiological failure and relapse may be increased in patients treated with cefixime compared to fluoroquinolones in three small trials published over 14 years ago: clinical failure (risk ratio (RR) 13.39, 95% confidence interval (CI) 3.24 to 55.39; 2 trials, 240 participants; low-certainty evidence); microbiological failure (RR 4.07, 95% CI 0.46 to 36.41; 2 trials, 240 participants; low-certainty evidence); relapse (RR 4.45, 95% CI 1.11 to 17.84; 2 trials, 220 participants; low-certainty evidence). Time to defervescence in participants treated with cefixime may be longer compared to participants treated with fluoroquinolones (mean difference (MD) 1.74 days, 95% CI 0.50 to 2.98, 3 trials, 425 participants; low-certainty evidence). Cephalosporin (ceftriaxone) versus azithromycin Ceftriaxone may result in a decrease in clinical failure compared to azithromycin, and it is unclear whether ceftriaxone has an effect on microbiological failure compared to azithromycin in two small trials published over 18 years ago and in one more recent trial, all conducted in participants under 18 years of age: clinical failure (RR 0.42, 95% CI 0.11 to 1.57; 3 trials, 196 participants; low-certainty evidence); microbiological failure (RR 1.95, 95% CI 0.36 to 10.64, 3 trials, 196 participants; very low-certainty evidence). It is unclear whether ceftriaxone increases or decreases relapse compared to azithromycin (RR 10.05, 95% CI 1.93 to 52.38; 3 trials, 185 participants; very low-certainty evidence). Time to defervescence in participants treated with ceftriaxone may be shorter compared to participants treated with azithromycin (mean difference of -0.52 days, 95% CI -0.91 to -0.12; 3 trials, 196 participants; low-certainty evidence). Cephalosporin (ceftriaxone) versus fluoroquinolones It is unclear whether ceftriaxone has an effect on clinical failure, microbiological failure, relapse, and time to defervescence compared to fluoroquinolones in three trials published over 28 years ago and two more recent trials: clinical failure (RR 3.77, 95% CI 0.72 to 19.81; 4 trials, 359 participants; very low-certainty evidence); microbiological failure (RR 1.65, 95% CI 0.40 to 6.83; 3 trials, 316 participants; very low-certainty evidence); relapse (RR 0.95, 95% CI 0.31 to 2.92; 3 trials, 297 participants; very low-certainty evidence) and time to defervescence (MD 2.73 days, 95% CI -0.37 to 5.84; 3 trials, 285 participants; very low-certainty evidence). It is unclear whether ceftriaxone decreases convalescent faecal carriage compared to the fluoroquinolone gatifloxacin (RR 0.18, 95% CI 0.01 to 3.72; 1 trial, 73 participants; very low-certainty evidence) and length of hospital stay may be longer in participants treated with ceftriaxone compared to participants treated with the fluoroquinolone ofloxacin (mean of 12 days (range 7 to 23 days) in the ceftriaxone group compared to a mean of 9 days (range 6 to 13 days) in the ofloxacin group; 1 trial, 47 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

Based on very low- to low-certainty evidence, ceftriaxone is an effective treatment for adults and children with enteric fever, with few adverse effects. Trials suggest that there may be no difference in the performance of ceftriaxone compared with azithromycin, fluoroquinolones, or chloramphenicol. Cefixime can also be used for treatment of enteric fever but may not perform as well as fluoroquinolones.  We are unable to draw firm general conclusions on comparative contemporary effectiveness given that most trials were small and conducted over 20 years previously. Clinicians need to take into account current, local resistance patterns in addition to route of administration when choosing an antimicrobial.

Clinical manifestations and microbiological features between indigenous and imported enteric fever in Taiwan, 2010-2020

Previous studies had showed that indigenous clones of Salmonella Typhi and S. Paratyphi were originally imported from other countries in Taiwan. We presented the clinical manifestations and laboratory findings of indigenous and imported enteric fever cases in Taiwan in the current decade. We retrospectively reviewed typhoid and paratyphoid fever cases in two medical centers of Chang Gung Memorial Hospitals in 2010-2020. A total of 37 enteric fever cases including 24 typhoid fever and 13 paratyphoid fever were recorded. There were 20 indigenous cases, 16 imported cases, and one indetermined case. Splenomegaly and hepatitis were more frequent in typhoid fever than in paratyphoid fever (P < 0.05). Imported cases had more ciprofloxacin non-susceptibility rate (8/16, 50.0%) than indigenous cases (2/20, 10%). Indigenous ciprofloxacin non-susceptible S. Typhi isolates were found in 2018. One indigenous S. Paratyphi B isolate was multi-drug resistant (MDR) to chloramphenicol, ampicillin, and trimethoprim/sulfamethoxazole.

Salmonella Paratyphi B; Public Health and Parental Choice: When to Treat Asymptomatic Carriers of Infection?

BACKGROUND

Salmonella Paratyphi B (Paratyphoid B) is a rare infection and a notifiable disease in England. Disease is typically mild, and chronic carriage in children has been described in endemic countries. Almost all cases in England are imported, with very few cases of community transmission reported.

METHODS

The aim of this work was to describe an unusual cluster of Paratyphoid B cases transmitted within England, examining clinical, epidemiologic and microbiologic data. Detailed phylogenetic analysis is presented to corroborate public health epidemiologic links between cases.

RESULTS

One child had recently returned from an endemic area and had mild gastrointestinal symptoms. One year later, 2 other children with no travel history developed invasive disease requiring hospitalization. Epidemiologic links confirmed person-to-person spread between these three cases. All isolates of S. Paratyphi B (n = 93) received by the Gastrointestinal Bacteria Reference Unit between 2014 and 2019 were typed using whole genome sequencing. Three cases of Paratyphoid B were identified in the same geographical location over a 2-year period. S. Paratyphi B strains isolated from the stool and blood of the three cases were closely linked (0-5 single-nucleotide polymorphisms) using whole genome sequencing.

CONCLUSIONS

This case series highlights the potential public health risks of paratyphoid B and the range of pediatric complications associated with this illness, especially in younger children. Although rare, chronic carriage of Paratyphoid B can lead to transmission in nonendemic areas and should be considered in all children presenting with signs of enteric fever even where there is no history of foreign travel.

Prevalence of Enteric Fever Pathogens Isolated from Blood Culture at a Tertiary Care Centre

INTRODUCTION

Typhoid fever and paratyphoid fever commonly called as enteric fever is a life-threatening illness caused by Salmonella serotype Typhi and Salmonella serotype Paratyphi, respectively. It is a major public health issue in underdeveloped and developing countries. The aim of the study is to find out the prevalence of enteric fever pathogens in blood culture of patients attending a tertiary care centre.

METHODS

A descriptive cross-sectional study was conducted in 3483 blood samples of patients attending a tertiary care centre, with the history and symptoms suspicious of enteric fever during one year period from mid-September 2019 to mid-September 2020 after ethical approval from the institutional review committee. Isolates were identified by standard microbiological methods and tested for in vitro antibiotic susceptibility by modified kirby-bauer disc diffusion method. The obtained data was entered and analyzed in WHONET 5.6 program, point estimate at 95% was calculated along with frequency and proportion for binary data.

RESULTS

In our study, enteric fever pathogens were isolated from 18 (0.51%) blood samples. Out of which, Salmonella Paratyphi A was isolated from 10 (8.19%) and Salmonella Typhi was isolated from 8 (6.55%) blood samples. Other serotypes were not isolated. Antimicrobial susceptibility test showed that salmonella species that was isolated were sensitive to most of the drugs.

CONCLUSIONS

Prevalence of enteric fever pathogens was lesser compared to other studies. Varying degrees of antibiotic resistance among isolated enteric fever pathogens necessitates continuous surveillance of the susceptibility patterns. Prudent use of antimicrobials, active infection control practices and stringent antibiotic policy should be implemented to prevent emergence of antibiotic resistance and future outbreaks.

Salmonella Typhi and Paratyphi A infections in Cambodian children, 2012-2016

OBJECTIVES

Enteric fever remains an important diagnostic and treatment challenge in febrile children living in the tropics. In the context of a national Salmonella enterica serovar Paratyphi A outbreak, the objective of this retrospective study was to compare features of S. Typhi and S. Paratyphi A infections in Cambodian children.

METHODS

Clinical and laboratory features were reviewed for 192 blood culture-confirmed children with S. Typhi and S. Paratyphi A infections presenting to a paediatric referral hospital in Siem Reap, 2012-2016.

RESULTS

Children with S. Typhi infections were younger, were more likely to have chills and/or diarrhoea, and were more frequently hospitalized than those with S. Paratyphi A infections. Over three quarters (88.3%) of S. Typhi isolates were multidrug-resistant, compared to none of the S. Paratyphi A.

CONCLUSIONS

In this small study of Cambodian children, S. Typhi infections were more severe than S. Paratyphi A infections. Antibiotic resistance limits treatment options for enteric fever in this population.

Treatment responses to Azithromycin and Ciprofloxacin in uncomplicated Salmonella Typhi infection: A comparison of Clinical and Microbiological Data from a Controlled Human Infection Model

BACKGROUND

The treatment of enteric fever is complicated by the emergence of antimicrobial resistant Salmonella Typhi. Azithromycin is commonly used for first-line treatment of uncomplicated enteric fever, but the response to treatment may be sub-optimal in some patient groups when compared with fluoroquinolones.

METHODS

We performed an analysis of responses to treatment with azithromycin (500mg once-daily, 14 days) or ciprofloxacin (500mg twice-daily, 14 days) in healthy UK volunteers (18-60 years) enrolled into two Salmonella controlled human infection studies. Study A was a single-centre, open-label, randomised trial. Participants were randomised 1:1 to receive open-label oral ciprofloxacin or azithromycin, stratified by vaccine group (Vi-polysaccharide, Vi-conjugate or control Men-ACWY vaccine). Study B was an observational challenge/re-challenge study, where participants were randomised to challenge with Salmonella Typhi or Salmonella Paratyphi A. Outcome measures included fever clearance time, blood-culture clearance time and a composite measure of prolonged treatment response (persistent fever ≥38.0°C for ≥72 hours, persistently positive S. Typhi blood cultures for ≥72 hours, or change in antibiotic treatment). Both trials are registered with ClinicalTrials.gov (NCT02324751 and NCT02192008).

FINDINGS

In 81 participants diagnosed with S. Typhi in two studies, treatment with azithromycin was associated with prolonged bacteraemia (median 90.8 hours [95% CI: 65.9-93.8] vs. 20.1 hours [95% CI: 7.8-24.3], p<0.001) and prolonged fever clearance times <37.5°C (hazard ratio 2.4 [95%CI: 1.2-5.0]; p = 0.02). Results were consistent when studies were analysed independently and in a sub-group of participants with no history of vaccination or previous challenge. A prolonged treatment response was observed significantly more frequently in the azithromycin group (28/52 [54.9%]) compared with the ciprofloxacin group (1/29 [3.5%]; p<0.001). In participants treated with azithromycin, observed systemic plasma concentrations of azithromycin did not exceed the minimum inhibitory concentration (MIC), whilst predicted intracellular concentrations did exceed the MIC. In participants treated with ciprofloxacin, the observed systemic plasma concentrations and predicted intracellular concentrations of ciprofloxacin exceeded the MIC.

INTERPRETATION

Azithromycin at a dose of 500mg daily is an effective treatment for fully sensitive strains of S. Typhi but is associated with delayed treatment response and prolonged bacteraemia when compared with ciprofloxacin within the context of a human challenge model. Whilst the cellular accumulation of azithromycin is predicted to be sufficient to treat intracellular S. Typhi, systemic exposure may be sub-optimal for the elimination of extracellular circulating S. Typhi. In an era of increasing antimicrobial resistance, further studies are required to define appropriate azithromycin dosing regimens for enteric fever and to assess novel treatment strategies, including combination therapies.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT02324751 and NCT02192008).

Treatment Response in Enteric Fever in an Era of Increasing Antimicrobial Resistance: An Individual Patient Data Analysis of 2092 Participants Enrolled into 4 Randomized, Controlled Trials in Nepal

Background.

Enteric fever, caused by Salmonella Typhi and Salmonella Paratyphi A, is the leading cause of bacterial febrile disease in South Asia.

Methods.

Individual data from 2092 patients with enteric fever randomized into 4 trials in Kathmandu, Nepal, were pooled. All trials compared gatifloxacin with 1 of the following comparator drugs: cefixime, chloramphenicol, ofloxacin, or ceftriaxone. Treatment outcomes were evaluated according to antimicrobial if S. Typhi/Paratyphi were isolated from blood. We additionally investigated the impact of changing bacterial antimicrobial susceptibility on outcome.

Results.

Overall, 855 (41%) patients had either S. Typhi (n = 581, 28%) or S. Paratyphi A (n = 274, 13%) cultured from blood. There were 139 (6.6%) treatment failures with 1 death. Except for the last trial with ceftriaxone, the fluoroquinolone gatifloxacin was associated with equivalent or better fever clearance times and lower treatment failure rates in comparison to all other antimicrobials. However, we additionally found that the minimum inhibitory concentrations (MICs) against fluoroquinolones have risen significantly since 2005 and were associated with increasing fever clearance times. Notably, all organisms were susceptible to ceftriaxone throughout the study period (2005-2014), and the MICs against azithromycin declined, confirming the utility of these alternative drugs for enteric fever treatment.

Conclusion.

The World Health Organization and local government health ministries in South Asia still recommend fluoroquinolones for enteric fever. This policy should change based on the evidence provided here. Rapid diagnostics are urgently required given the large numbers of suspected enteric fever patients with a negative culture.

A 23-year retrospective investigation of Salmonella Typhi and Salmonella Paratyphi isolated in a tertiary Kathmandu hospital

BACKGROUND

Salmonella serovars Typhi (S. Typhi) and Paratyphi A (S. Paratyphi A), the causative agents of enteric fever, have been routinely isolated organisms from the blood of febrile patients in the Kathmandu Valley since the early 1990s. Susceptibility against commonly used antimicrobials for treating enteric fever has gradually changed throughout South Asia since this time, posing serious treatment challenges. Here, we aimed to longitudinally describe trends in the isolation of Salmonella enterica and assess changes in their antimicrobial susceptibility in Kathmandu over a 23-year period.

METHODS

We conducted a retrospective analysis of standardised microbiological data from April 1992 to December 2014 at a single healthcare facility in Kathmandu, examining time trends of Salmonella-associated bacteraemia and the corresponding antimicrobial susceptibility profiles of the isolated organisms.

RESULTS

Over 23 years there were 30,353 positive blood cultures. Salmonella enterica accounted for 65.4% (19,857/30,353) of all the bacteria positive blood cultures. S. Typhi and S. Paratyphi A were the dominant serovars, constituting 68.5% (13,592/19,857) and 30.5% (6,057/19,857) of all isolated Salmonellae. We observed (i) a peak in the number of Salmonella-positive cultures in 2002, a year of heavy rainfall and flooding in the Kathmandu Valley, followed by a decline toward pre-flood baseline by 2014, (ii) an increase in the proportion of S. Paratyphi in all Salmonella-positive cultures between 1992 and 2014, (iii) a decrease in the prevalence of MDR for both S. Typhi and S. Paratyphi, and (iv) a recent increase in fluoroquinolone non-susceptibility in both S. Typhi and S. Paratyphi isolates.

CONCLUSIONS

Our work describes significant changes in the epidemiology of Salmonella enterica in the Kathmandu Valley during the last quarter of a century. We highlight the need to examine current treatment protocols for enteric fever and suggest a change from fluoroquinolone monotherapy to combination therapies of macrolides or cephalosporins along with older first-line antimicrobials that have regained their efficacy.

Enteric Fever in a Tertiary Paediatric Hospital: A Retrospective Six-Year Review

INTRODUCTION

Enteric fever is a multisystemic infection which largely affects children. This study aimed to analyse the epidemiology, clinical presentation, treatment and outcome of paediatric enteric fever in Singapore.

MATERIALS AND METHODS

A retrospective review of children diagnosed with enteric fever in a tertiary paediatric hospital in Singapore was conducted from January 2006 to January 2012. Patients with positive blood cultures for Salmonella typhi or paratyphi were identified from the microbiology laboratory information system. Data was extracted from their case records.

RESULTS

Of 50 enteric fever cases, 86% were due to Salmonella typhi, with 16.3% being multidrug resistant (MDR) strains. Sixty-two percent of S. typhi isolates were of decreased ciprofloxacin susceptibility (DCS). Five cases were both MDR and DCS. The remaining 14% were Salmonella paratyphi A. There were only 3 indigenous cases. Ninety-four percent had travelled to typhoid-endemic countries, 70.2% to the Indian subcontinent and the rest to Indonesia and Malaysia. All patients infected with MDR strains had travelled to the Indian subcontinent. Anaemia was a significant finding in children with typhoid, as compared to paratyphoid fever (P = 0.04). Although all children were previously well, 14% suffered severe complications including shock, pericardial effusion and enterocolitis. None had typhoid vaccination prior to their travel to developing countries.

CONCLUSION

Enteric fever is largely an imported disease in Singapore and has contributed to significant morbidity in children. The use of typhoid vaccine, as well as education on food and water hygiene to children travelling to developing countries, needs to be emphasised.

Typhoid fever

Control of typhoid fever relies on clinical information, diagnosis, and an understanding for the epidemiology of the disease. Despite the breadth of work done so far, much is not known about the biology of this human-adapted bacterial pathogen and the complexity of the disease in endemic areas, especially those in Africa. The main barriers to control are vaccines that are not immunogenic in very young children and the development of multidrug resistance, which threatens efficacy of antimicrobial chemotherapy. Clinicians, microbiologists, and epidemiologists worldwide need to be familiar with shifting trends in enteric fever. This knowledge is crucial, both to control the disease and to manage cases. Additionally, salmonella serovars that cause human infection can change over time and location. In areas of Asia, multidrug-resistant Salmonella enterica serovar Typhi (S Typhi) has been the main cause of enteric fever, but now S Typhi is being displaced by infections with drug-resistant S enterica serovar Paratyphi A. New conjugate vaccines are imminent and new treatments have been promised, but the engagement of local medical and public health institutions in endemic areas is needed to allow surveillance and to implement control measures.

Frequency of Blood Culture Isolates and their Antibiogram in a Teaching hospital

INTRODUCTION

Bloodstream infections are associated with significant patient morbidity and mortality. Antimicrobial susceptibility patterns should guide the choice of empiric antimicrobial regimens for patients with bacteremia.

METHODS

Blood sample received from the patient attending Nepal Medical College and Teaching Hospital from March, 2012 - August, 2012 were subjected to culture. Isolate identification and antimicrobial susceptibility testing was done by standard microbiological method.

RESULTS

Out of the total 2,766 blood samples, 368 (13.3%) showed bacterial growth. The percentage of neonatal septicemia was 368 (13.3%). Staphylococcus aureus (28%) was the most common isolates followed by Salmonella enterica Serotype Typhi (22%), Coagulase negative Staphylococci (9.5%), Salmonella enterica Serotype Paratyphi ((7.6%) and Klebsiella pneumoniae (7.6%). 26.3% of the isolates of Staphylococcus aureus were oxacillin resistant. Most of the gram positive organisms were susceptible to amikacin and vancomycin and showed high level resistance to cefuroxime and cotrimoxazole. Out of 109 isolates of typhoid bacilli, 95.3% were resistant to nalidixic acid,79% to ciprofloxacin and 60.5% to ofloxacin. More than 50% of the isolates of Klebsiella pneumoniae and Escherichia coli showed resistance to cephalosporins and cotrimoxazole. Acinetobacter sp. showed high resistance (more than 60%) to ceftriaxone and ofloxacin. More than 20% of the isolates of Pseudomonas aeruginosa were resistant to ciprofloxacin and amikacin.

CONCLUSIONS

Ongoing surveillance for antimicrobial susceptibility remains essential, and will enhance efforts to identify resistance and attempt to limit its spread.

Treatment of Japanese patients with enteric fever using azithromycin and MIC levels for causative organisms

In Japan azithromycin (AZM) has been used to treat enteric fever caused by bacteria with resistance to fluoroquinolones; however, the dose, length of treatment and effectiveness of AZM among Japanese patients with enteric fever is unclear. We studied 5 Japanese adults and 1 Japanese child with enteric fever (4 had typhoid fever and 2 had paratyphoid fever) who were treated with oral AZM. The treatment regimens were: 1,000 mg as a single or in 2 divided doses on the 1st day, followed by 500 mg as a single dose daily for 5-6 additional days, or 500 mg as a single dose daily for 10 days. The minimum inhibitory concentrations (MICs) for AZM against 5 causative organisms were investigated with an E-test. Good clinical results were observed in the 5 adult patients but treatment failure was seen in the 1 child patient with typhoid fever; no adverse reactions were found. MICs of AZM were 4 microg/ml against S. Typhi in 2 patients, 8 microg/ml against S. Typhi in 2 patients, and 32 microg/ml against S. Paratyphi A in 1 patient. Our findings indicate AZM may be a reasonable choice for treatment of Japanese adult patients with enteric fever.

WITHDRAWN: Azithromycin for treating uncomplicated typhoid and paratyphoid fever (enteric fever)

BACKGROUND

Review status: Current question - no update intended. Azithromycin treatments are included in the review: Fluoroquinolones for treating typhoid and paratyphoid fever (enteric fever). (Thaver D, Zaidi AKM, Critchley JA, Azmatullah A, Madni SA, Bhutta ZA. Fluoroquinolones for treating typhoid and paratyphoid fever (enteric fever). Cochrane Database of Systematic Reviews 2008, Issue 4. Art. No.: CD004530. DOI: 10.1002/14651858.CD004530.pub3.)   This latter review is being updated, and will be published in late 2011.Enteric fever (typhoid and paratyphoid fever) is potentially fatal. Infection with drug-resistant strains of the causative organism Salmonella enterica serovar Typhi or Paratyphi increases morbidity and mortality. Azithromycin may have better outcomes in people with uncomplicated forms of the disease.

OBJECTIVES

To compare azithromycin with other antibiotics for treating uncomplicated enteric fever.

SEARCH STRATEGY

In August 2008, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library 2008, Issue 3), MEDLINE, EMBASE, LILACS, and mRCT. We also searched conference proceedings, reference lists, and contacted researchers and a pharmaceutical company.

SELECTION CRITERIA

Randomized controlled trials comparing azithromycin with other antibiotics for treating children and adults with uncomplicated enteric fever confirmed by cultures of S. Typhi or Paratyphi in blood and/or stool.

DATA COLLECTION AND ANALYSIS

Both authors independently extracted data and assessed the risk of bias. Dichotomous data were presented and compared using the odds ratio, and continuous data were reported as arithmetic means with standard deviations and were combined using the mean difference (MD). Both were presented with 95% confidence intervals (CI).

MAIN RESULTS

Seven trials involving 773 participants met the inclusion criteria. The trials used adequate methods to generate the allocation sequence and conceal allocation, and were open label. Three trials exclusively included adults, two included children, and two included both adults and children; all were hospital inpatients. One trial evaluated azithromycin against chloramphenicol and did not demonstrate a difference for any outcome (77 participants, 1 trial). When compared with fluoroquinolones in four trials, azithromycin significantly reduced clinical failure (OR 0.48, 95% CI 0.26 to 0.89; 564 participants, 4 trials) and duration of hospital stay (MD -1.04 days, 95% CI -1.73 to -0.34 days; 213 participants, 2 trials); all four trials included people with multiple-drug-resistant or nalidixic acid-resistant strains of S. Typhi or S. Paratyphi. We detected no statistically significant difference in the other outcomes. Compared with ceftriaxone, azithromycin significantly reduced relapse (OR 0.09, 95% CI 0.01 to 0.70; 132 participants, 2 trials) and not other outcome measures. Few adverse events were reported, and most were mild and self limiting.

AUTHORS' CONCLUSIONS

Azithromycin appears better than fluoroquinolone drugs in populations that included participants with drug-resistant strains. Azithromycin may perform better than ceftriaxone.

Fluoroquinolones for treating typhoid and paratyphoid fever (enteric fever)

BACKGROUND

Typhoid and paratyphoid are febrile illnesses, due to a bacterial infection, which remain common in many low- and middle-income countries. The World Health Organization (WHO) currently recommends the fluoroquinolone antibiotics in areas with known resistance to the older first-line antibiotics.

OBJECTIVES

To evaluate fluoroquinolone antibiotics for treating children and adults with enteric fever.

SEARCH STRATEGY

We searched The Cochrane Infectious Disease Group Specialized Register (February 2011); Cochrane Central Register of Controlled Trials (CENTRAL), published in The Cochrane Library (2011, Issue 2); MEDLINE (1966 to February 2011); EMBASE (1974 to February 2011); and LILACS (1982 to February 2011). We also searched the metaRegister of Controlled Trials (mRCT) in February 2011.

SELECTION CRITERIA

Randomized controlled trials examining fluoroquinolone antibiotics, in people with blood, stool or bone marrow culture-confirmed enteric fever.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the trial's methodological quality and extracted data. We calculated risk ratios (RR) for dichotomous data and mean difference for continuous data with 95% confidence intervals (CI).Comparative effectiveness has been interpreted in the context of; length of treatment, dose, year of study, known levels of antibiotic resistance, or proxy measures of resistance such as the failure rate in the comparator arm.

MAIN RESULTS

Twenty-six studies, involving 3033 patients, are included in this review.Fluoroquinolones versus older antibiotics (chloramphenicol, co-trimoxazole, amoxicillin and ampicillin)In one study from Pakistan in 2003-04, high clinical failure rates were seen with both chloramphenicol and co-trimoxazole, although resistance was not confirmed microbiologically. A seven-day course of either ciprofloxacin or ofloxacin were found to be superior. Older studies of these comparisons failed to show a difference (six trials, 361 participants).In small studies conducted almost two decades ago, the fluoroquinolones were demonstrated to have fewer clinical failures than ampicillin and amoxicillin (two trials, 90 participants, RR 0.11, 95% CI 0.02 to 0.57).Fluoroquinolones versus current second-line options (ceftriaxone, cefalexin, and azithromycin)The two studies comparing a seven day course of oral fluoroquinolones with three days of intravenous ceftriaxone were too small to detect important differences between antibiotics should they exist (two trials, 89 participants).In Pakistan in 2003-04, no clinical or microbiological failures were seen with seven days of either ciprofloxacin, ofloxacin or cefixime (one trial, 139 participants). In Nepal in 2005, gatifloxacin reduced clinical failure and relapse compared to cefixime, despite a high prevalence of NaR in the study population (one trial, 158 participants, RR 0.04, 95% CI 0.01 to 0.31).Compared to a seven day course of azithromycin, a seven day course of ofloxacin had a higher rate of clinical failures in populations with both multi-drug resistance (MDR) and nalidixic acid resistance (NaR) enteric fever in Vietnam in 1998-2002 (two trials, 213 participants, RR 2.20, 95% CI 1.23 to 3.94). However, a more recent study from Vietnam in 2004-05, detected no difference between gatifloxacin and azithromycin with both drugs performing well (one trial, 287 participants).

AUTHORS' CONCLUSIONS

Generally, fluoroquinolones performed well in treating typhoid, and maybe superior to alternatives in some settings. However, we were unable to draw firm general conclusions on comparative contemporary effectiveness given that resistance changes over time, and many studies were small. Policy makers and clinicians need to consider local resistance patterns in choosing a fluoroquinolone or alternative.There is some evidence that the newest fluoroquinolone, gatifloxacin, remains effective in some regions where resistance to older fluoroquinolones has developed. However, the different fluoroquinolones have not been compared directly in trials in these settings.

Genotypic and phenotypic differentiation of Salmonella enterica serovar Paratyphi B in Malaysia

Abstract. Salmonella enterica serovar Paratyphi B is known to cause either paratyphoid fever or gastroenteritis. Differentiation of Salmonella ser. Paratyphi B into biotype Java (d-tartrate fermenting, dT+) and biotype Paratyphi B (d-tartrate non-fermenting, dT) is important for Salmonella epidemiology. This study applied a PCR approach to differentiate the two biotypes to augment the conventional biochemical method and to determine the antibiograms and genomic diversity of Malaysian S. Paratyphi B. Among 100 strains tested (clinical, 86; non-humans, 14), only two clinical strains were confirmed as biotype Paratyphi B as indicated by both lead acetate test and PCR. Antibiotic resistance rates were as follows: streptomycin 18%, sulphonamides 13%, ampicillin 10%, chloramphenicol 4%, tetracycline 3%, cefotaxime 2%, cefpodoxime 2%, ceftazidime 2%, gentamicin 1% and trimethoprim 1%. None showed resistance towards amoxicillin-clavulanic acid, ceftiofur, ciprofloxacin, nalidixic acid and trimethoprim-sulphamethoxazole. Seven strains showed multidrug resistance towards 3 or more classes of antimicrobial agents. REP-PCR and PFGE generated 32 and 76 different profiles, respectively. PFGE (D = 0.99) was more discriminative than REP-PCR (D = 0.93) and antimicrobial susceptibility test (D = 0.48) in subtyping the strains. Strains isolated 18 years apart (1982 - 2008) from different localities in Malaysia were clonally related as demonstrated by REP-PCR and PFGE, indicating that these strains were stable and widely distributed. In some clusters, strains isolated from different sources (clinical, food and animal) were grouped together. Thus, biotype Java was the most common biotype of Salmonella ser. Paratyphi B in Malaysia. The PCR approach is highly recommended due to its simplicity, specificity and ease of operation. The level of antimicrobial resistance among Salmonella ser. Paratyphi B remained relatively low in Malaysia but the emergence of resistance to cephalosporins is a cause for concern.

Salmonella enterica serovar Paratyphi A: an emerging cause of febrile illness in Nepal

With an aim to evaluate the isolation rate and antibiotic susceptibility pattern in Salmonella enterica serovar Typhi and S. Paratyphi A, 656 blood samples collected from clinically diagnosed enteric fever patients at National Public Health Laboratory, Nepal during January through December 2008 were processed. Isolates were identified by standard microbiological procedures including serotyping. Antibiotic susceptibility testing was performed by disc diffusion method and minimum inhibitory concentration (MIC) to ciprofloxacin, ofloxacin and nalidixic acid was determined by agar dilution method following CLSI guidelines. Altogether 59 isolates of S. Typhi (49.15%) and S. Paratyphi A (50.85%) were recovered. A total of 80% isolates were resistant to nalidixic acid with S. Paratyphi A (93%) showing significantly higher resistance (P < 0.05) compared to S. Typhi (66%). The nalidixic acid resistant S. Paratyphi A strains required significantly higher MICs (P < 0.001) to quinolone (MIC expressed as mean +/- SD for nalidixic acid 477.87 +/- 87.02 microg/mL, ofloxacin 1.8 +/- 0.63 microg/mL, ciprofloxacin 0.62 +/- 0.3 microg/mL) compared with that of S. Typhi (nalidixic acid 173.18 +/- 72.03 microg/mL, ofloxacin 0.43 +/- 0.11 microg/mL, ciprofloxacin 0.25 microg/mL). Increased MIC of fluoroquinolone (FQ) is of particular concern in emerging strains of S. Paratyphi A as exposure to these drugs fuels up further development of full FQ resistant populations. Use of FQs as the first-line drugs for empirical therapy and management of enteric fever in areas where these strains are prevalent is questionable and requires an urgent review.

In vitro susceptibility of typhoidal Salmonellae against newer antimicrobial agents: a search for alternate treatment options

OBJECTIVES

To determine the minimum inhibitory concentrations (MICs) of ceftriaxone, azithromycin, pefloxacin, cefipime and imipenem for Salmonella Typhi (S. Typhi) and Paratyphi.

METHODS

One hundred and fifty four isolates of Salmonella Typhi and S. Paratyphi A, B and C growing in blood culture were selected. MICs of ceftriaxone, azithromycin, pefloxacin, cefipime and imipenem were performed by agar dilution method as recommended by clinical laboratory standard institutes.

RESULTS

MIC90 of azithromycin and pefloxacin was 8 microg/ml, cefipime was 0.06 microg/ml and imipenem was 0.5 microg/ml. None of the strains were found to be resistant to ceftriaxone but 3 isolates showed higher MIC value of 2 microg/ml.

CONCLUSION

Azithromycin appears a suitable alternate for the treatment of typhoid in the community. Imipenem and cefipime are good options in complicated cases to be treated in hospital settings. Pefloxacin cannot be used as MICs are higher. Presence of isolates with higher MIC of ceftriaxone is serious and stresses upon continuous laboratory surveillance to guide clinicians appropriately.

Occurrence & antibiogram of Salmonella Typhi & S. Paratyphi A isolated from Rourkela, Orissa

BACKGROUND & OBJECTIVES

Almost round-the-year occurrence of Salmonella Typhi and Salmonella Paratyphi A has been noticed in Rourkela since last 13 and five years respectively. The incidence of infection along with the antibiogram of these two serotypes in this area were carried out.

METHODS

The study was carried out at Ispat General Hospital, Rourkela, India, between January 2005 and December 2008 with 5340 blood samples collected from patients with suspected enteric fever and pyrexia of unknown origin. Isolation, identification and antibiogram of the causative organisms were performed according to standard bacteriological procedures.

RESULTS

A total of 298 Salmonella isolates showed an overall per cent positivity of 5.58. Multidrug resistance was found in 11.96 per cent and 15.62 per cent isolates of S. Typhi and S. Paratyphi A respectively. Less than 2 per cent isolates of Salmonella showed resistance to ciprofloxacin. A resistance of 3.0 to 6.25 per cent against third generation cephalosporins was observed among the salmonella isolates.

INTERPRETATION & CONCLUSION

A round-the-year occurrence of Salmonella spp. in Rourkela might have been due to the presence of a considerable number of carriers in the locality, poor sanitation in nearby slum areas, and inadequate and contaminated community water supply at times. Higher degree of susceptibility among S. Typhi isolates against various antibiotics was encouraging, but increasing trend of resistance observed among S. Paratyphi A isolates was a matter of concern.

Global trends in typhoid and paratyphoid Fever

Typhoid and paratyphoid fever continue to be important causes of illness and death, particularly among children and adolescents in south-central and Southeast Asia, where enteric fever is associated with poor sanitation and unsafe food and water. High-quality incidence data from Asia are underpinning efforts to expand access to typhoid vaccines. Efforts are underway to develop vaccines that are immunogenic in infants after a single dose and that can be produced locally in countries of endemicity. The growing importance of Salmonella enterica serotype Paratyphi A in Asia is concerning. Antimicrobial resistance has sequentially emerged to traditional first-line drugs, fluoroquinolones, and third-generation cephalosporins, posing patient treatment challenges. Azithromycin has proven to be an effective alternative for treatment of uncomplicated typhoid fever. The availability of full genome sequences for S. enterica serotype Typhi and S. enterica serotype Paratyphi A confirms their place as monomorphic, human-adapted pathogens vulnerable to control measures if international efforts can be redoubled.

Prevalence of Salmonella typhi and paratyphi infection in children: a hospital based study

The purpose of this study was to find out the prevalence and antibiotic sensitivity pattern of Salmonella typhi and paratyphi isolated from children presenting with fever at Kanti Children's Hospital in Kathmandu, Nepal. A total of 9,856 blood samples collected for culture during one year period (April 2007 to March 2008) were included in the study. Out of total, 235 (2.0%) were positive for S. typhi and paratyphi A. Of the total positive, 195 (83.0%) were S. typhi and 40 (17.0%) were S. paratyphi A. The growth positive rate in two genders (M: 53.2% and F: 46.8%) was not significant (P > 0.05). Over two-third of cases were clustered in the age-group of 1-10 years. The occurrence of infections was common in summer months (rainy season). S. typhi was found to be most sensitive to cefotaxime (100.0%) followed by ceftriaxone (98.9%), ofloxacin (93.5%), cotrimoxazole (93.5%) and chloramphenicol (93.2%) and was least sensitive to amoxyccilin (66.7%) followed by ciprofloxacin (86.6%). S. paratyphi also was found to be most sensitive to cefotaxime (100.0%), followed by ceftriaxone (97.4%), cotrimoxazole (97.1%) and chloramphenicol (92.5%) and was least sensitive to amoxycillin (15.0%) followed by ciprofloxacin (51.3%) and ofloxacin (70.3%).

Fluoroquinolones for treating typhoid and paratyphoid fever (enteric fever)

BACKGROUND

Fluoroquinolones are recommended as first-line therapy for typhoid and paratyphoid fever (enteric fever), but how they compare with other antibiotics and different fluoroquinolones is unclear.

OBJECTIVES

To evaluate fluoroquinolone antibiotics for treating enteric fever in children and adults compared with other antibiotics, different fluoroquinolones, and different durations of fluoroquinolone treatment.

SEARCH STRATEGY

In November 2007, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library 2007, Issue 4), MEDLINE, EMBASE, LILACS, mRCT, conference proceedings, and reference lists.

SELECTION CRITERIA

Randomized controlled trials of fluoroquinolones in people with blood or bone marrow culture-confirmed enteric fever.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the trials' methodological quality and extracted data. We calculated odds ratios (OR) for dichotomous data with 95% confidence intervals (CI). We analysed trials with greater than 60% children separately from trials of mostly adults.

MAIN RESULTS

Of 38 included trials, 22 had unclear allocation concealment and 34 did not use blinding. Four trials included exclusively children, seven had both adults and children, and three studied outpatients.

ADULTS

Among primary outcomes (clinical failure, microbiological failure, and relapse), compared with chloramphenicol, fluoroquinolones were not statistically significantly different for clinical failure (594 participants) or microbiological failure (378 participants), but they reduced clinical relapse (OR 0.14, 95% CI 0.04 to 0.50; 467 participants, 6 trials). We detected no statistically significant difference versus co-trimoxazole (82 participants, 2 trials) or azithromycin (152 participants, 2 trials). Fluoroquinolones reduced clinical failure compared with ceftriaxone (OR 0.08, 95% CI 0.01 to 0.45; 120 participants, 3 trials), but not microbiological failure or relapse. Versus cefixime, fluoroquinolones reduced clinical failure (OR 0.05, 95% CI 0.01 to 0.24; 238 participants; 2 trials) and relapse (OR 0.18, 95% CI 0.03 to 0.91; 218 participants, 2 trials).

CHILDREN

In children with high proportions of nalidixic acid-resistant strains, older fluoroquinolones increased clinical failures compared with azithromycin (OR 2.67, 95% CI 1.16 to 6.11; 125 participants, 1 trial), with no differences using newer fluoroquinolones (285 participants, 1 trial). Fluoroquinolones and cefixime were not statistically significantly different (82 participants, 1 trial). Trials comparing different durations of fluoroquinolone treatment were not statistically significantly different (889 participants, 9 trials). Norfloxacin had more clinical failures than other fluoroquinolones (417 participants, 5 trials).

AUTHORS' CONCLUSIONS

Trials were small and methodological quality varied. In adults, fluoroquinolones may be better for reducing clinical relapse rates compared to chloramphenicol. Data are limited for other comparisons, particularly in children.

Azithromycin for treating uncomplicated typhoid and paratyphoid fever (enteric fever)

BACKGROUND

Enteric fever (typhoid and paratyphoid fever) is potentially fatal. Infection with drug-resistant strains of the causative organism Salmonella enterica serovar Typhi or Paratyphi increases morbidity and mortality. Azithromycin may have better outcomes in people with uncomplicated forms of the disease.

OBJECTIVES

To compare azithromycin with other antibiotics for treating uncomplicated enteric fever.

SEARCH STRATEGY

In August 2008, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library 2008, Issue 3), MEDLINE, EMBASE, LILACS, and mRCT. We also searched conference proceedings, reference lists, and contacted researchers and a pharmaceutical company.

SELECTION CRITERIA

Randomized controlled trials comparing azithromycin with other antibiotics for treating children and adults with uncomplicated enteric fever confirmed by cultures of S. Typhi or Paratyphi in blood and/or stool.

DATA COLLECTION AND ANALYSIS

Both authors independently extracted data and assessed the risk of bias. Dichotomous data were presented and compared using the odds ratio, and continuous data were reported as arithmetic means with standard deviations and were combined using the mean difference (MD). Both were presented with 95% confidence intervals (CI).

MAIN RESULTS

Seven trials involving 773 participants met the inclusion criteria. The trials used adequate methods to generate the allocation sequence and conceal allocation, and were open label. Three trials exclusively included adults, two included children, and two included both adults and children; all were hospital inpatients. One trial evaluated azithromycin against chloramphenicol and did not demonstrate a difference for any outcome (77 participants, 1 trial). When compared with fluoroquinolones in four trials, azithromycin significantly reduced clinical failure (OR 0.48, 95% CI 0.26 to 0.89; 564 participants, 4 trials) and duration of hospital stay (MD -1.04 days, 95% CI -1.73 to -0.34 days; 213 participants, 2 trials); all four trials included people with multiple-drug-resistant or nalidixic acid-resistant strains of S. Typhi or S. Paratyphi. We detected no statistically significant difference in the other outcomes. Compared with ceftriaxone, azithromycin significantly reduced relapse (OR 0.09, 95% CI 0.01 to 0.70; 132 participants, 2 trials) and not other outcome measures. Few adverse events were reported, and most were mild and self limiting.

AUTHORS' CONCLUSIONS

Azithromycin appears better than fluoroquinolone drugs in populations that included participants with drug-resistant strains. Azithromycin may perform better than ceftriaxone.

Alternatives to ciprofloxacin use for enteric Fever, United kingdom

Alternatives to Ciprofloxacin Use for Enteric Fever, United Kingdom

[A case of Salmonella paratyphi A infection in Poland]

Paratyphoid fever is an acute infection caused by Salmonella paratyphi A, B or C. The disease is transmitted from person to person by fecal-oral way. Typical for typhoid fever are splenomegaly, bradycardia, fever, constipation or mild diarrhoea oftten associated with abdominal tenderness. We present the case of patient who was infected by Salmonella paratyphi C while his travelling in Asia.

Guillain-Barré syndrome associated with Salmonella paratyphi A

A 31-year-old Nepali man was admitted to the intensive care unit with a 3-day history of fever associated with four-limb weakness, followed by difficulty in swallowing. The patient came from Nepal 20 days before admission. On examination the patient was conscious and appeared ill, with a temperature of 38.0 degrees C. His four limbs were weak (grades 2-3) and he was areflexic with mild facial weakness and absent gag reflex. Brain CT and MRI were normal. Cerebrospinal fluid analysis showed high protein. A neurophysiologic study showed data consistent with motor axonal polyradiculopathy. The patient was diagnosed with Guillain-Barré syndrome (GBS), and intravenous immunoglobulin (0.4 g/kg day for 5 days) was administered. On the third hospitalization day, the patient developed respiratory failure for which he was intubated and mechanically ventilated. On the same day, blood samples grew Salmonella paratyphi A (S. paratyphi A), which was sensitive to ceftriaxone. The patient was then diagnosed with GBS associated with S. paratyphi A, and treated with ceftriaxon (2 g administered intravenously, daily for 10 days). On the eleventh hospitalization day the patient was weaned from ventilator and extubated successfully. Subsequently, the patient improved, his fever subsided, and he regained muscle power satisfactorily.

Paratyphoid sepsis

A large for gestational age male baby was born to a healthy young primigravida, on L-thyroxime, at 40 weeks by caesarean delivery in a tertiary care hospital. The baby had episodes of hypoglycemia during his immediate four postnatal days in the nursery that were successfully managed with intravenous glucose administration. The baby became unwell on day 5 and had a positive sepsis-screening test. Blood culture revealed a multidrug susceptible S. Paratyphi A strain, which he probably acquired on the first or second postnatal day from the contaminated expressed breast milk or the formula feed.

Ciprofloxacin treatment failure in a case of typhoid fever caused by Salmonella enterica serotype Paratyphi A with reduced susceptibility to ciprofloxacin

This report describes a case of ciprofloxacin treatment failure in a patient with enteric fever caused by Salmonella enterica serotype Paratyphi A. The organism was isolated from a blood culture from a patient who was treated with oral ciprofloxacin (500 mg every 12 h) for 13 days. The organism showed reduced susceptibility to ciprofloxacin (MIC 0.75 μg ml−1) and was resistant to nalidixic acid. The patient was then placed on intravenous ceftriaxone (1 g every 12 h) and responded within 3 days. The patient was discharged after 9 days on ceftriaxone with no relapse on follow-up. This case adds to the increasing incidence of treatment failures with ciprofloxacin in typhoid fever caused by typhoid salmonellae with reduced susceptibility to ciprofloxacin. It also highlights the inadequacy of current laboratory methods for fluoroquinolone susceptibility testing in adequately predicting in vivo activity of ciprofloxacin against typhoid salmonellae and supports calls for new guidelines for fluoroquinolone susceptibility testing of these organisms.

Increasing prevalence of Salmonella enterica serotype Paratyphi-A in patients with enteric fever in a periurban slum setting of Kolkata, India

A sudden rise in the occurrence of Salmonella enterica serotype Paratyphi-A (SPTA) was noted in a longitudinal community-based study in Kolkata, India, during 2004 - 2005. We compared the incidence rate of Salmonella enterica serotype Typhi (ST) and SPTA and their antimicrobial susceptibility pattern. Rate of isolation of SPTA was 1.5 times higher than that of ST, a trend detected for the first time in that particular focus. Almost all the isolates were sensitive to Gentamycin and Norfloxacin. Most of the strains (90%) were sensitive to Ciprofloxacin. Two thirds of the strains were also sensitive to Chloramphenicol. The high occurrence of SPTA in the present study could be the signal of the emergence of SPTA as a pathogen in India. Quinolone derivatives (namely, Ciprofloxacin, Norfloxacin and Chloramphenicol) can be suggested as drugs of choice for treatment of enteric fever caused by SPTA. Future vaccination strategies should include bivalent vaccines with protection capacities against both ST as well as SPTA.

A case of pyrexia from abroad

A case of pyrexia from abroad presenting to the emergency department is discussed. The causes of such pyrexia are outlined and the investigations are described. We stress that vaccination is not foolproof from acquiring an infection from abroad.

Emergence of Salmonella enterica serotype Paratyphi A as a major cause of enteric fever in Kathmandu, Nepal

We performed pulsed-field gel electrophoresis (XbaI) on 114 bloodstream isolates of Salmonella enterica serotype Paratyphi A and S. enterica serotype Typhi collected from febrile patients in Kathmandu, Nepal. Of the 56 S. Paratyphi A isolates, 51 (91%) were indistinguishable, which suggests the emergence of a single clone. In contrast, only 21 (36%) of the 58 S. Typhi isolates exhibited a common genotype, which is consistent with endemic disease from multiple sources.

Deep-seated resistance in relapsed paratyphoid fever

We describe a case of relapsed paratyphoid fever in which the isolate had reduced susceptibility to ciprofloxacin due to a rare mutation within the gyrA gene. 18fluorodeoxyglucose positron emission tomography scanning identified deep-seated infection including unsuspected aortitis and highlights the utility of novel imaging techniques to improve our understanding and treatment of this disease.

Salmonella paratyphi endocarditis

Endocarditis is a rare complication of salmonellosis. The most frequently observed species is Salmonella typhi. Endocarditis caused by Salmonella paratyphi is extremely rare with only three previous cases documented in the medical literature. We report a case of endocarditis caused by Salmonella paratyphi in an otherwise healthy young patient, with full recovery after appropriate antibiotic treatment.

Management of splenic abscess in children by percutaneous drainage

BACKGROUND/PURPOSE

Isolated splenic abscesses are rare in pediatric patients. The recommended treatment in the literature has been in favor of splenectomy, although conservative treatment with splenic preservation is being increasingly reported. We report successful management of 4 pediatric patients with splenic abscess by needle aspirations and antibiotics.

MATERIALS AND METHODS

Four children (aged 7-11 years; male-female, 3:1) were admitted in our institution with history of high-grade fever with chills, anorexia, left hypochondrial pain, and splenomegaly. One child was a known case of thalassemia, and one had a history of typhoid fever. The others did not have any predisposing condition. Ultrasonography (USG) and computed tomographic scan of the abdomen showed a solitary abscess in the spleen in 2 patients and multiple abscesses in the other 2. Ultrasonography-guided needle aspiration in 3 cases revealed purulent fluid, which, on culture, grew Escherichia coli in 1 case, Salmonella paratyphi A in 1 case, but sterile in 1 case. Blood culture was sterile in all the cases, but Widal's test was positive in 2 patients. Treatment protocol included USG-guided needle aspiration of pus along with intravenous ceftriaxone, metronidazole, and amikacin for 3 to 12 weeks.

RESULTS

All 4 patients showed a good response to conservative treatment. Serial USG showed gradual resolution of abscess, and none was subjected to splenectomy.

CONCLUSION

Isolated splenic abscess in children can be successfully treated with needle aspirations and intravenous antibiotics, thereby avoiding splenectomy.

Enteric (typhoid) fever in travelers

The incidence of enteric (typhoid) fever in travelers is estimated to be approximately 3-30 cases per 100,000 travelers to developing countries. Recently, it is become clear that travelers who are visiting friends and relatives, especially travelers to the Indian subcontinent, seem to be the most vulnerable to enteric fever and require special attention for prevention. Recent concerns are the increasing incidence of paratyphoid fever in Asia, which is not covered by available typhoid vaccines, and the emergence of infections caused by antibiotic-resistant strains (including strains resistant to fluoroquinolones). Typhoid vaccination is recommended for most travelers to moderate- to high-risk countries. Because of the nonspecific clinical presentation of enteric fever, a high index of suspicion is important in febrile travelers who have traveled to areas of endemicity.

[Typhoid and paratyphoid fever in children]

BACKGROUND

Febrile illness without focal symptoms in a child who has visited tropical or sub-tropical areas is an increasing health problem in western countries. In the department of paediatrics at Ullevaal University Hospital, malaria, typhoid and paratyphoid fever are the most frequent infectious diseases acquired in tropical or sub-tropical areas.

MATERIALS AND METHODS

We describe all 31 children under 16 admitted between 1998 and 2003 who had blood cultures positive for Salmonella typhi or Salmonella paratyphi A or B.

RESULTS

Nearly all the children were second or third generation immigrants from the Indian subcontinent. Fever was the main symptom at onset. Out of 31 salmonella strains, 8 showed reduced sensitivity to quinolones, which are the drugs of choice. Clinical poor response to treatment is associated with reduced sensitivity to nalidixic acid in vitro.

CONCLUSION

Blood cultures prior to administration of antibiotics are important in providing correct diagnosis and appropriate treatment. Before visiting endemic areas, groups at risk should be informed that there are vaccines available against typhoid fever.

Fluoroquinolones for treating typhoid and paratyphoid fever (enteric fever)

BACKGROUND

Fluoroquinolones are recommended as first-line therapy for typhoid and paratyphoid fever, but how they compare with other cheaper antibiotics and different fluoroquinolones is unclear.

OBJECTIVES

To evaluate fluoroquinolone antibiotics for treating enteric fever in children and adults compared with other antibiotics, different fluoroquinolones, and different treatment durations of the same fluoroquinolone.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group Specialized Register (August 2004), CENTRAL (The Cochrane Library Issue 3, 2004), MEDLINE (1966 to August 2004), EMBASE (1974 to August 2004), LILACS (1982 to August 2004), conference proceedings, reference lists, and contacted researchers.

SELECTION CRITERIA

Randomized controlled trials of fluoroquinolones in people with blood or bone marrow culture-confirmed enteric fever.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed the methodological quality of trials and extracted data. We calculated the odds ratio (OR) for dichotomous data with 95% confidence intervals. We analysed norfloxacin separately.

MAIN RESULTS

Thirty-three trials met the inclusion criteria; 22 had unclear allocation concealment, and 29 were not blinded. Three trials exclusively included children, and two studied outpatients. The main analysis examined clinical failure, microbiological failure, and relapse. Compared with chloramphenicol, fluoroquinolones were not statistically significantly different for clinical (544 participants) or microbiological failure (378 participants) in adults; they reduced clinically diagnosed relapse in adults (OR 0.14, 0.04 to 0.50; 467 participants, 6 trials), but this was not statistically significant in participants with blood culture-confirmed relapse (121 participants, 2 trials). Compared with co-trimoxazole, we detected no statistically significant difference (82 participants, 2 trials). Among adults, fluoroquinolones reduced clinical failure compared with ceftriaxone (OR 0.08, 0.01 to 0.45; 120 participants, 3 trials), but showed no difference for microbiological failure or relapse. We detected no statistically significant difference between fluoroquinolones and cefixime (80 participants, 1 trial) or azithromycin (152 participants, 2 trials). In trials of hospitalized children, fluoroquinolones were not statistically significantly different from ceftriaxone (60 participants, 1 trial, involving norfloxacin) or cefixime (82 participants, 1 trial). Norfloxacin had more clinical failures than other fluoroquinolones (417 participants, 5 trials). Trials comparing different durations of fluoroquinolone treatment showed no statistically significant differences (693 participants, 8 trials).

AUTHORS' CONCLUSIONS

Many trials were small, and methodological quality varied widely. Although enteric fever most commonly affects children, trials in this group were particularly sparse. Insufficient data in all comparisons preclude any firm conclusions to be made regarding superiority of fluoroquinolones over first-line antibiotics in children and adults.

Multiple antimicrobial resistant Salmonella enterica serovar Paratyphi B variant Java in cattle: a case report

An epidemiological investigation of a calf rearing premises and a closely associated dairy herd was carried out after the isolation of Salmonella enterica serovar Paratyphi B variant Java phage type 3b variant 2 from clinically diseased calves on the premises. The isolate was resistant to ampicillin, chloramphenicol, streptomycin, sulphonamides, tetracyclines, trimethoprim and cefoperazone. The organism was widespread on the calf unit and was also recovered from the dairy premises, mainly from groups of weaned calves. The investigation was extended to 10 epidemiologically linked farms but no S Java was isolated from any of the 40 to 60 samples collected from each premises. Molecular studies showed that the S Java isolates were genetically most similar to isolates from cases of human disease associated with ornamental fish tanks or feed. Long PCR and resistance gene profiling identified a resistance island which was indistinguishable from the human 'fish tank' strain of S Java and animal and human epidemic strains of S Typhimurium DT104. The isolates were clearly distinguished from multi-resistant S Java strains commonly associated with continental poultry. This is the first report of S Java with this resistance pattern in Great Britain.

Suboptimal clinical response to ciprofloxacin in patients with enteric fever due to Salmonella spp. with reduced fluoroquinolone susceptibility: a case series

BACKGROUND

Salmonella spp. with reduced susceptibility to fluoroquinolones have higher than usual MICs to these agents but are still considered "susceptible" by NCCLS criteria. Delayed treatment response to fluoroquinolones has been noted, especially in cases of enteric fever due to such strains. We reviewed the ciprofloxacin susceptibility and clinical outcome of our recent enteric fever cases.

METHODS

Salmonella enterica Serotype Typhi (S. Typhi) and Serotype Paratyphi (S. Paratyphi) blood culture isolates (1998-2002) were tested against nalidixic acid by disk diffusion (DD) and agar dilution (AD) and to ciprofloxacin by AD using NCCLS methods and interpretive criteria. Reduced fluoroquinolone susceptibility was defined as a ciprofloxacin MIC of 0.125-1.0 mg/L. The clinical records of patients treated with ciprofloxacin for isolates with reduced fluoroquinolone susceptibility were reviewed.

RESULTS

Seven of 21 (33%) S. Typhi and S. Paratyphi isolates had reduced susceptibility to fluoroquinolones (MIC range 0.125-0.5 mg/L). All 7 were nalidixic acid resistant by DD (no zone) and by AD (MIC 128- >512 mg/L). The other 14 isolates were nalidixic acid susceptible and fully susceptible to ciprofloxacin (MIC range 0.015-0.03 mg/L). Five of the 7 cases were treated initially with oral ciprofloxacin. One patient remained febrile on IV ciprofloxacin until cefotaxime was added, with fever recurrence when cefotaxime was discontinued. Two continued on oral or IV ciprofloxacin alone but had prolonged fevers of 9-10 days duration, one was switched to IV beta-lactam therapy after remaining febrile for 3 days on oral/IV ciprofloxacin and one was treated successfully with oral ciprofloxacin. Four of the 5 required hospitalization.

CONCLUSIONS

Our cases provide further evidence that reduced fluoroquinolone susceptibility of S. Typhi and S. Paratyphi is clinically significant. Laboratories should test extra-intestinal Salmonella spp. for reduced fluoroquinolone susceptibility.

Occurrence of Salmonella typhi and Salmonella paratyphi in Jordan

In order to justify the surveillance control system and hygiene policy in Jordan, this study evaluated the occurrence of diarrhoea during the period 1988-2000, focusing on cases caused by Salmonella typhi and Salmonella paratyphi. From January 1988 to December 2000, the number of notified diarrhoeal cases by the Ministry of Health in Jordan was 1,399,563 million. Other groups of patients confined to the Governorate of Amman was diagnosed at Al-Battikhi Medical Laboratories. One-way ANOVA and Least Significant Difference (LSD) were carried out for statistical analysis. The number of reported diarrhea cases was 1,399,563, 53.0% were males, and 47.0% were females, among them, 80.3% were < 20 years and 19.7%, were > 20 years. Out of 245,255 patients tested for S. typhi and S. pararyphi, positive stool culture were 1992 (0.6%). Out of these, 960 (48.2%) were males and 1,032 (51.8%) were females (P = 0.028). The highest incidence rate (10.8) was observed in the year 1993, while the lowest incidence rate (0.9) was found in year 2000. A significant difference (P < 0.001) was found between the number of S. typhi and S. Paratyphi cases and year. The seasonal variation was also found to be significant (P < 0.0001), with the summer period showing the highest incident rate. A significant difference (P < 0.001) was observed between number of typhoid and paratyphoid cases and districts. A significance difference between number of typhoid and paratyphoid cases with age and sex. The group most affected was school age and adolescence. The demographic situation plays an important role in reporting typhoid and paratyphoid cases, where there might be an urgent indication for a better surveillance control system on water resources and disposal systems. S. typhi and S. paratyphi antibiotics resistance pattern showed they were resistant to tetracycline (56.0%, 58.0%), ampicillin (45.0%, 48.0%), trimethoprim (43.0%, 47.0%), cephtazidime (12.0%, 13.5%) chloramphenicol (6.8%, 7.2%), gentamycin (3.0%, 4.0%) neomycin (2.1. 1.8%), calvulanic acid (augmentin (1.4%, 2.2%) and norofloxacin (0.92%, 1.1%). Susceptibility to amikacin, ciprofloxacin, cetfriaxone, ofloxacine, imepenim, cefixime and cefotaxime was 100.0%. The increase in percentage of antibiotic resistant strain might indicate a need for a further prescribing policy for treatment.