Bacterial Isolates and Antibiotic Sensitivity among Gambian Children with Severe Acute Malnutrition

Antimicrobial resistance in Enterobacterales infections among children in sub-Saharan Africa: a systematic review and meta-analysis

Background

The burden of antimicrobial resistance (AMR) has been estimated to be the highest in sub-Saharan Africa (SSA). The current study estimated the proportion of drug-resistant Enterobacterales causing infections in SSA children.

Methods

We searched MEDLINE/PubMed, Embase and the Cochrane Library to identify retrospective and prospective studies published from 01/01/2005 to 01/06/2022 reporting AMR of Enterobacterales causing infections in sub-Saharan children (0-18 years old). Studies were excluded if they had unclear documentation of antimicrobial susceptibility testing methods or fewer than ten observations per bacteria. Data extraction and quality appraisal were conducted by two authors independently. The primary outcome was the proportion of Enterobacterales resistant to antibiotics commonly used in paediatrics. Proportions were combined across studies using mixed-effects logistic regression models per bacteria and per antibiotic. Between-study heterogeneity was assessed using the I2 statistic. The protocol was registered with PROSPERO (CRD42021260157).

Findings

After screening 1111 records, 122 relevant studies were included, providing data on more than 30,000 blood, urine and stool isolates. Escherichia coli and Klebsiella spp. were the predominant species, both presenting high proportions of resistance to third-generation cephalosporins, especially in blood cultures: 40.6% (95% CI: 27.7%-55%; I2: 85.7%, number of isolates (n): 1032) and 84.9% (72.8%-92.2%; I2: 94.1%, n: 2067), respectively. High proportions of resistance to other commonly used antibiotics were also observed. E. coli had high proportions of resistance, especially for ampicillin (92.5%; 95% CI: 76.4%-97.9%; I2: 89.8%, n: 888) and gentamicin (42.7%; 95% CI: 30%-56.5%; I2: 71.9%, n: 968). Gentamicin-resistant Klebsiella spp. were also frequently reported (77.6%; 95% CI: 65.5%-86.3%; I2: 91.6%, n: 1886).

Interpretation

High proportions of resistance to antibiotics commonly used for empirical treatment of infectious syndromes were found for Enterobacterales in sub-Saharan children. There is a critical need to better identify local patterns of AMR to inform and update clinical guidelines for better treatment outcomes.

Funding

No funding was received.

Antibiotics susceptibility patterns of uropathogenic bacteria: a cross-sectional analytic study at Kanifing General Hospital, The Gambia

BACKGROUND

Antimicrobial resistance poses a public health threat for the treatment of community-acquired urinary tract infections. This study determined the susceptibility patterns of uropathogens and associated risk factors among outpatients diagnosed with urinary tract infections at the Kanifing General Hospital in the Gambia.

METHODS

A cross-sectional analytic study was conducted among patients with suspected urinary tract infections at Kanifing General Hospital from March to May 2021. Data on socio-demographic and other risk factors were collected from the study participants using a structured pre-tested questionnaire. Mid-stream urine samples were collected, and bacteria identification and antimicrobial susceptibility testing done using standard microbiological methods. Descriptive and inferential statistical analysis were done to determine factors associated with urinary tract infection at 95% confidence level and a p -value < 0.05.

RESULTS

A total of 422 patients were enrolled with 82.5% (348/422) being females. The prevalence of community acquired urinary tract infection was 12.8% (54/422). Escherichia coli was the most prevalent isolate (74.1%, 40/54), followed by Klebsiella spp (8.5%, 10/54). Antimicrobial resistance was highest for Ampicillin (87.0%, 47/54), Trimethoprim/Sulfamethoxazole (77.8%, 42/54) and Tetracycline (75.9%, 41/54). Uropathogens sensitivity was 77.8% (42/54) for Nitrofurantoin and 75.9% (41/54) for Ceftazidime. Being female (aOR 5.90 95% CI = 1.48-23.67), previous history of urinary tract infection (aOR 2.34, 95% CI = 1.06-5.14), use of unprescribed antibiotics (aOR 2.0, 95% CI = 1.05-3.62) and having no formal education (aOR 8.02, 95% CI = 1.04-62.0) were significant factors associated for having uropathogenic bacterial infection.

CONCLUSION

E. coli was the most prevalent uropathogen isolated. Ciprofloxacin, Nitrofurantoin and Ceftazidime were the most sensitive antibiotics. Routine surveillance of susceptibility of uropathogenic bacteria would be helpful to update clinicians on the choice of antibiotics.

Impact of childhood malnutrition and intestinal microbiota on MDR infections

The global burden of infection from MDR organisms (MDROs) disproportionately affects children residing in low- and middle-income countries and those with increased healthcare exposure. These populations have high rates of malnutrition making them increasingly vulnerable to infection with intestinal-derived pathogens. Malnourished children experience increased incidence of intestinal carriage and invasive infection with intestinal-derived MDROs including ESBL- and carbapenemase-producing Enterobacterales. However, the relationship between malnutrition and MDRO infection remains to be clearly defined. Impairment in intestinal barrier function and innate and adaptive immunity in malnutrition increases the risk for infection with intestinal-derived pathogens, and there is an increasing appreciation of the role of the intestinal microbiota in this process. Current evidence from human studies and animal models suggests that diet and the intestinal microbiota influence each other to determine nutritional status, with important implications for infectious outcomes. These insights are crucial to developing microbiota-targeted strategies aimed at reversing the growing burden of MDRO infections in malnourished populations worldwide.

Antibiotic use and resistance in children with severe acute malnutrition and human immunodeficiency virus infection

Severe acute malnutrition (SAM) and human immunodeficiency virus (HIV) infection underlie a major proportion of the childhood disease burden in low- and middle-income countries. These diseases commonly co-occur and lead to higher risk of other endemic infectious diseases, thereby compounding the risk of mortality and morbidity. The widespread use of antibiotics as treatment and prophylaxis in childhood SAM and HIV infections, respectively, has reduced mortality and morbidity but canlead to increasing antibiotic resistance. Development of antibiotic resistance could render future infections untreatable. This review summarises the endemic co-occurrence of undernutrition, particularly SAM, and HIV in children, and current treatment practices, specifically WHO-recommended antibiotic usage. The risks and benefits of antibiotic treatment, prophylaxis and resistance are reviewed in the context of patients with SAM and HIV and associated sub-populations. Finally, the review highlights possible research areas and populations where antibiotic resistance progression can be studied to best address concerns associated with the future impact of resistance. Current antibiotic usage is lifesaving in complicated SAM and HIV-infected populations; nevertheless, increasing baseline resistance and infection remain a significant concern. In conclusion, antibiotic usage currently addresses the immediate needs of children in SAM and HIV endemic regions; however, it is prudent to evaluate the impact of antibiotic use on resistance dynamics and long-term child health.

Invasive atypical non-typhoidal Salmonella serovars in The Gambia

Invasive non-typhoidal Salmonella (iNTS) disease continues to be a significant public health problem in sub-Saharan Africa. Common clinical misdiagnosis, antimicrobial resistance, high case fatality and lack of a vaccine make iNTS a priority for global health research. Using whole genome sequence analysis of 164 invasive Salmonella isolates obtained through population-based surveillance between 2008 and 2016, we conducted genomic analysis of the serovars causing invasive Salmonella diseases in rural Gambia. The incidence of iNTS varied over time. The proportion of atypical serovars causing disease increased over time from 40 to 65 % compared to the typical serovars Enteritidis and Typhimurium that decreased from 30 to 12 %. Overall iNTS case fatality was 10%, but case fatality associated with atypical iNTS alone was 10 %. Genetic virulence factors were identified in 14/70 (20 %) typical serovars and 45/68 (66 %) of the atypical serovars and were associated with: invasion, proliferation and/or translocation (Clade A); and host colonization and immune modulation (Clade G). Among Enteritidis isolates, 33/40 were resistant to four or more of the antimicrobials tested, except ciprofloxacin, to which all isolates were susceptible. Resistance was low in Typhimurium isolates, but all 16 isolates were resistant to gentamicin. The increase in incidence and proportion of iNTS disease caused by atypical serovars is concerning. The increased proportion of atypical serovars and the high associated case fatality may be related to acquisition of specific genetic virulence factors. These factors may provide a selective advantage to the atypical serovars. Investigations should be conducted elsewhere in Africa to identify potential changes in the distribution of iNTS serovars and the extent of these virulence elements.

Impact of routine vaccination against Haemophilus influenzae type b in The Gambia: 20 years after its introduction

Background

In 1997, The Gambia introduced three primary doses of Haemophilus influenzae type b (Hib) conjugate vaccine without a booster in its infant immunisation programme along with establishment of a population-based surveillance on Hib meningitis in the West Coast Region (WCR). This surveillance was stopped in 2002 with reported elimination of Hib disease. This was re-established in 2008 but stopped again in 2010. We aimed to re-establish the surveillance in WCR and to continue surveillance in Basse Health and Demographic Surveillance System (BHDSS) in the east of the country to assess any shifts in the epidemiology of Hib disease in The Gambia.

Methods

In WCR, population-based surveillance for Hib meningitis was re-established in children aged under-10 years from 24 December 2014 to 31 March 2017, using conventional microbiology and Real Time Polymerase Chain Reaction (RT-PCR). In BHDSS, population-based surveillance for Hib disease was conducted in children aged 2-59 months from 12 May 2008 to 31 December 2017 using conventional microbiology only. Hib carriage survey was carried out in pre-school and school children from July 2015 to November 2016.

Results

In WCR, five Hib meningitis cases were detected using conventional microbiology while another 14 were detected by RT-PCR. Of the 19 cases, two (11%) were too young to be protected by vaccination while seven (37%) were unvaccinated. Using conventional microbiology, the incidence of Hib meningitis per 100 000-child-year (CY) in children aged 1-59 months was 0.7 in 2015 (95% confidence interval (CI) = 0.0-3.7) and 2.7 (95% CI = 0.7-7.0) in 2016. In BHDSS, 25 Hib cases were reported. Nine (36%) were too young to be protected by vaccination and five (20%) were under-vaccinated for age. Disease incidence peaked in 2012-2013 at 15 per 100 000 CY and fell to 5-8 per 100 000 CY over the subsequent four years. The prevalence of Hib carriage was 0.12% in WCR and 0.38% in BHDSS.

Conclusions

After 20 years of using three primary doses of Hib vaccine without a booster Hib transmission continues in The Gambia, albeit at low rates. Improved coverage and timeliness of vaccination are of high priority for Hib disease in settings like Gambia, and there are currently no clear indications of a need for a booster dose.

Genomic epidemiology of Escherichia coli isolates from a tertiary referral center in Lilongwe, Malawi

Antimicrobial resistance (AMR) is a global threat, including in sub-Saharan Africa. However, little is known about the genetics of resistant bacteria in the region. In Malawi, there is growing concern about increasing rates of antimicrobial resistance to most empirically used antimicrobials. The highly drug resistant Escherichia coli sequence type (ST) 131, which is associated with the extended spectrum β-lactamase blaCTX-M-15, has been increasing in prevalence globally. Previous data from isolates collected between 2006 and 2013 in southern Malawi have revealed the presence of ST131 and the blaCTX-M-15 gene in the country. We performed whole genome sequencing (WGS) of 58 clinical E. coli isolates at Kamuzu Central Hospital, a tertiary care centre in central Malawi, collected from 2012 to 2018. We used Oxford Nanopore Technologies (ONT) sequencing, which was performed in Malawi. We show that ST131 is observed more often (14.9% increasing to 32.8%) and that the blaCTX-M-15 gene is occurring at a higher frequency (21.3% increasing to 44.8%). Phylogenetics indicates that isolates are highly related between the central and southern geographic regions and confirms that ST131 isolates are contained in a single group. All AMR genes, including blaCTX-M-15, were widely distributed across sequence types. We also identified an increased number of ST410 isolates, which in this study tend to carry a plasmid-located copy of blaCTX-M-15 gene at a higher frequency than blaCTX-M-15 occurs in ST131. This study confirms the expanding nature of ST131 and the wide distribution of the blaCTX-M-15 gene in Malawi. We also highlight the feasibility of conducting longitudinal genomic epidemiology studies of important bacteria with the sequencing done on site using a nanopore platform that requires minimal infrastructure.

The prevalence and risk of urinary tract infection in malnourished children: a systematic review and meta-analysis

BACKGROUND

There are vast differences in prevalence rates of urinary tract infection (UTI) reported among malnourished children globally. We conducted a systematic review and meta-analysis to provide estimates of pooled prevalence of UTI among these children and combined UTI risk in comparison with their well-nourished counterparts.

METHODS

We systematically searched electronic databases (MEDLINE, EMBASE, ISI Web of Science and African Journals Online; date of the last search: 22 December 2018) for studies reporting either the prevalence of UTI in malnourished children or parallel healthy controls. Eligible primary studies were observational studies of children in English Language reporting UTI prevalence with background malnutrition or with enough data to compute these estimates, as well as studies which reported at the same time UTI prevalence in healthy controls. We synthesized published prevalence rates or associations (odds ratios [OR]) between malnutrition and UTI and their 95% confidence intervals (CI) using random effects meta-regression and explored potential heterogeneity determinants using meta-regression analysis. This review is registered with PROSPERO, number- CRD42018084765.

RESULTS

We included 26 cross-sectional and 8 case-control studies reporting on UTI prevalence in malnourished children, and in malnourished children vs. healthy controls, respectively. The pooled prevalence of UTI in 3294 malnourished children was 17% (95% CI, 13, 21%). Heterogeneity was high (I2 = 87.6%; Tau2 = 0.06) as studies varied in their sample size, degree of malnutrition, and study period. Multivariate meta-regression model, including these factors, explained 34.6% of the between-study variance. Pooled OR of UTI in association with malnutrition in 2051 children (1052 malnourished children vs. 999 controls) was 2.34 (95% CI, 1.15, 3.34), with lower between-study heterogeneity (I2 = 53.6%; Tau2 = 0.47).

CONCLUSIONS

UTI is more prevalent in malnourished children than in their well-nourished counterparts. Screening and treatment for UTI should be incorporated in the management protocol of malnourished children to improve disease outcomes.

Antibiotic use on paediatric inpatients in a teaching hospital in the Gambia, a retrospective study

Background

Antibiotics are useful but increasing resistance is a major problem. Our objectives were to assess antibiotic use and microbiology testing in hospitalized children in the Gambia.

Methods

We conducted a retrospective analysis of paediatric inpatient data at The Edward Francis Small Teaching Hospital in Banjul, The Gambia. We extracted relevant data from the admission folders of all patients (aged > 28 days to 15 years) admitted in 2015 (January–December), who received at least one antibiotic for 24 h. We also reviewed the microbiology laboratory record book to obtain separate data for the bacterial isolates and resistance test results of all the paediatric inpatients during the study period.

Results

Over half of the admitted patients received at least one antibiotic during admission (496/917) with a total consumption of 670.7 Days of Antibiotic Therapy/1000 Patient-Days. The clinical diagnoses included an infectious disease for 398/496, 80.2% of the patients on antibiotics, pneumonia being the most common (184/496, 37.1%). There were 51 clinically relevant bacterial isolates, Klebsiella species being the most common (12/51, 23.5%), mainly from urine (11/12, 91.7%). Antibiotic resistance was mainly to ampicillin (38/51, 74.5%), mainly reported as Coliform species 11/51, 21.6%.

Conclusions

More than half of the admitted patients received antibiotics. The reported antibiotic resistance was highest to the most commonly used antibiotics such as ampicillin. Efforts to maximize definitive antibiotic indication such as microbiological testing prior to start of antibiotics should be encouraged where possible for a more rational antibiotic use.

Impact of Childhood Malnutrition on Host Defense and Infection

The global impact of childhood malnutrition is staggering. The synergism between malnutrition and infection contributes substantially to childhood morbidity and mortality. Anthropometric indicators of malnutrition are associated with the increased risk and severity of infections caused by many pathogens, including viruses, bacteria, protozoa, and helminths. Since childhood malnutrition commonly involves the inadequate intake of protein and calories, with superimposed micronutrient deficiencies, the causal factors involved in impaired host defense are usually not defined. This review focuses on literature related to impaired host defense and the risk of infection in primary childhood malnutrition. Particular attention is given to longitudinal and prospective cohort human studies and studies of experimental animal models that address causal, mechanistic relationships between malnutrition and host defense. Protein and micronutrient deficiencies impact the hematopoietic and lymphoid organs and compromise both innate and adaptive immune functions. Malnutrition-related changes in intestinal microbiota contribute to growth faltering and dysregulated inflammation and immune function. Although substantial progress has been made in understanding the malnutrition-infection synergism, critical gaps in our understanding remain. We highlight the need for mechanistic studies that can lead to targeted interventions to improve host defense and reduce the morbidity and mortality of infectious diseases in this vulnerable population.

Should first-line empiric treatment strategies cover coagulase-negative staphylococcal infections in severely malnourished or HIV-infected children in Kenya?

Background

Bloodstream infection is a common cause of morbidity in children aged <5 years in developing countries. In studies reporting bacteremia in Africa, coagulase-negative Staphylococci (CoNS) are commonly isolated. However, it is currently unclear whether children who are highly susceptible to infection because of severe acute malnutrition (SAM) or HIV should be treated with antimicrobials specifically to cover CoNS. We aimed to determine the clinical significance of CoNS amongst children admitted to a rural hospital in Kenya in relation to nutritional and HIV status.

Methods

Systematically collected clinical and microbiological surveillance data from children aged 6–59 months admitted to Kilifi County Hospital (2007–2013) were analysed. Multivariable regression was used to test associations between CoNS isolation from blood cultures and SAM (MUAC <11.5cm or nutritional oedema (kwashiorkor)), and HIV serostatus; and among children with SAM or HIV, associations between CoNS isolation and mortality, duration of hospitalization and clinical features.

Results

CoNS were isolated from blood culture in 906/13,315 (6.8%) children, of whom 135/906 (14.9%) had SAM and 54/906 (6.0%) were HIV antibody positive. CoNS isolation was not associated with SAM (MUAC<11.5cm (aOR 1.11, 95% CI 0.88–1.40) or kwashiorkor (aOR 0.84, 95% CI 0.48–1.49)), or a positive HIV antibody test (aOR 1.25, 95% CI 0.92–1.71). Among children with SAM or a positive HIV antibody test, CoNS isolation was not associated with mortality or prolonged hospitalization.

Conclusion

In a large, systematic study, there was no evidence that antimicrobial therapy should specifically target CoNS amongst children with SAM or HIV-infection or exposure.

Antimicrobial resistance in West Africa: a systematic review and meta-analysis

Growing data suggest that antimicrobial-resistant bacterial infections are common in low- and middle-income countries. This review summarises the microbiology of key bacterial syndromes encountered in West Africa and estimates the prevalence of antimicrobial resistance (AMR) that could compromise first-line empirical treatment. We systematically searched for studies reporting on the epidemiology of bacterial infection and prevalence of AMR in West Africa within key clinical syndromes. Within each syndrome, the pooled proportion and 95% confidence interval were calculated for each pathogen-antibiotic pair using random-effects models. Among 281 full-text articles reviewed, 120 met the eligibility criteria. The majority of studies originated from Nigeria (70; 58.3%), Ghana (15; 12.5%) and Senegal (15; 12.5%). Overall, 43 studies (35.8%) focused on urinary tract infections (UTI), 38 (31.7%) on bloodstream infections (BSI), 27 (22.5%) on meningitis, 7 (5.8%) on diarrhoea and 5 (4.2%) on pneumonia. Children comprised the majority of subjects. Studies of UTI reported moderate to high rates of AMR to commonly used antibiotics including evidence of the emergence of cephalosporin resistance. We found moderate rates of AMR among common bloodstream pathogens to typical first-line antibiotics including ampicillin, cotrimoxazole, gentamicin and amoxicillin/clavulanate. Among S. pneumoniae strains isolated in patients with meningitis, levels of penicillin resistance were low to moderate with no significant resistance noted to ceftriaxone or cefotaxime. AMR was common in this region, particularly in hospitalized patients with BSI and both outpatient and hospitalized patients with UTI. This raises concern given the limited diagnostic capability and second-line treatment options in the public sector in West Africa.

Bacterial infections in HIV-infected children admitted with severe acute malnutrition in Durban, South Africa

BACKGROUND

Bacterial infections in HIV-infected children admitted with severe acute malnutrition (SAM) contribute to higher mortality and poorer outcomes. This study describes the spectrum of bacterial infections in antiretroviral treatment (ART)-naïve, HIV-infected children admitted with SAM.

METHODS

Between July 2012 and February 2015, 82 children were prospectively enrolled in the King Edward VIII Hospital, Durban. Specimens obtained on and during admission for microbiological evaluation, if clinically indicated, included blood, urine (obtained by catheterisation or suprapubic aspiration), induced sputum and cerebrospinal fluid. All positive bacterial cultures between admission and 30 days after enrollment were documented and characterised into samples taken either within 2 days of admission (infections on admission) or within 2-30 days of admission (hospital-acquired infections, HAIs).

RESULTS

On admission, 67% of patients had abnormal white blood cell counts (WBCC) (>12 or <4 × 10⁹/L) and 70% had elevated CRP; 65% were classified as severely immunosuppressed according to the WHO immunological classification.¹ A pathogen was isolated on the admission blood culture in four patients (6%) and in 27% of urine specimens. HAIs were predominately Gram-negative (39/43), and 39.5% were extended-spectrum β-lactamase-positive. Mortality was not significantly associated with isolation of a bacterial pathogen.

CONCLUSIONS

Routine pre-hospital administration of antibiotics as per the Integrated Management of Childhood Illness (IMCI) guidelines may be responsible for the low rates of positive admission blood cultures. HAIs with drug-resistant Gram-negative organisms are an area of concern and strategies to improve the prevention of HAIs in this vulnerable population are urgently needed.

A Systematic Review of the Incidence, Risk Factors and Case Fatality Rates of Invasive Nontyphoidal Salmonella (iNTS) Disease in Africa (1966 to 2014)

This study systematically reviews the literature on the occurrence, incidence and case fatality rate (CFR) of invasive nontyphoidal Salmonella (iNTS) disease in Africa from 1966 to 2014. Data on the burden of iNTS disease in Africa are sparse and generally have not been aggregated, making it difficult to describe the epidemiology that is needed to inform the development and implementation of effective prevention and control policies. This study involved a comprehensive search of PubMed and Embase databases. It documents the geographical spread of iNTS disease over time in Africa, and describes its reported incidence, risk factors and CFR. We found that Nontyphoidal Salmonella (NTS) have been reported as a cause of bacteraemia in 33 out of 54 African countries, spanning the five geographical regions of Africa, and especially in sub-Saharan Africa since 1966. Our review indicates that NTS have been responsible for up to 39% of community acquired blood stream infections in sub-Saharan Africa with an average CFR of 19%. Salmonella Typhimurium and Enteritidis are the major serovars implicated and together have been responsible for 91%% of the cases of iNTS disease, (where serotype was determined), reported in Africa. The study confirms that iNTS disease is more prevalent amongst Human Immunodeficiency Virus (HIV)-infected individuals, infants, and young children with malaria, anaemia and malnutrition. In conclusion, iNTS disease is a substantial cause of community-acquired bacteraemia in Africa. Given the high morbidity and mortality of iNTS disease in Africa, it is important to develop effective prevention and control strategies including vaccination.

The prevalence of urinary tract infection in children with severe acute malnutrition: a narrative review

This article aims to review the current evidence which shows that the prevalence of urinary tract infection (UTI) has been increasing in children with severe acute malnutrition (SAM). UTI remains one of the most common causes of febrile illness in pediatric practice. Most studies conducted among hospitalized children with complicated SAM have reported high prevalence rates of UTI. Clearly, the knowledge of baseline risk of UTI can help clinicians to make informed diagnostic and therapeutic decisions in these children. From the global reports reviewed in this article, UTI prevalence rates range from as low as 6% to as high as 37% in developing countries, while the most common bacterial isolates from urine cultures are Gram-negative coliform organisms such as Escherichia coli and Klebsiella species. These findings form the basis for the current diagnostic and therapeutic guidelines for clinicians managing children with complicated SAM. With the reported high prevalence of UTI among these children and concerns over antibiotic resistance, more extensive data are required using standardized microbiological methods. Thus, the assessment of the performance of urine dipsticks and microscopy against the gold standard urine culture is an important step toward strengthening the evidence for the therapeutic guidelines for UTI in children with SAM.

Salmonella Infections in The Gambia, 2005-2015

BACKGROUND

There are large data gaps in the epidemiology of diseases caused by Salmonella enterica in West Africa. Regional surveillance of Salmonella infections is necessary, especially with the emergence and spread of multidrug-resistant clones.

METHODS

Data on Salmonella isolated from various clinical specimens from patients from across The Gambia were collected and analyzed retrospectively from 2005 to April 2015. Antibiotic sensitivity testing of Salmonella isolates was performed by disk diffusion method. Serotyping and serogrouping of Salmonella isolates was performed using standard microbiology techniques.

RESULTS

Two hundred three Salmonella isolates were isolated from 190 patients: 52% (106/203) from blood and 39% (79/203) from stool specimens. Salmonella was also isolated from urine, aspirates, cerebrospinal fluid, wounds, and abscesses. The prevalence of Salmonella in blood cultures was 0.8% (106/13,905). Of the serotyped salmonellae, 14% (21/152) were Salmonella enterica serovar Typhi, whereas 86% (131/152) were serovars other than Typhi (nontyphoidal Salmonella). Of the 102 typed NTS isolates, 40% (41) were Salmonella enterica serovar Typhimurium, 10% (10) were Salmonella enterica serovar Enteritidis, and 3% (3) were Salmonella enterica serovar Arizonae. Overall, 70% (142/203) of the salmonellae were pansusceptible. Multidrug resistance was found in 4% (9/203) of the isolates, 3 of which were Salmonella Enteritidis.

CONCLUSIONS

Salmonellae are associated with a wide spectrum of invasive and noninvasive infections across all ages in The Gambia. There is evidence of multidrug resistance in salmonellae that warrants vigilant monitoring and surveillance.

Progressive Changes in the Plasma Metabolome during Malnutrition in Juvenile Pigs

Severe acute malnutrition (SAM) is one of the leading nutrition-related causes of death in children under five years of age. The clinical features of SAM are well documented, but a comprehensive understanding of the development from a normal physiological state to SAM is lacking. Characterizing the temporal metabolomic change may help to understand the disease progression and to define nutritional rehabilitation strategies. Using a piglet model we hypothesized that a progressing degree of malnutrition induces marked plasma metabolite changes. Four-week-old weaned pigs were fed a nutrient-deficient maize diet (MAL) or nutritionally optimized reference diet (REF) for 7 weeks. Plasma collected weekly was subjected to LC-MS for a nontargeted profiling of metabolites with abundance differentiation. The MAL pigs showed markedly reduced body-weight gain and lean-mass proportion relative to the REF pigs. Levels of eight essential and four nonessential amino acids showed a time-dependent deviation in the MAL pigs from that in the REF. Choline metabolites and gut microbiomic metabolites generally showed higher abundance in the MAL pigs. The results demonstrated that young malnourished pigs had a profoundly perturbed metabolism, and this provides basic knowledge about metabolic changes during malnourishment, which may be of help in designing targeted therapeutic foods for refeeding malnourished children.

Epidemiological and clinical profile of hospitalized children with moderate and severe acute malnutrition in South India

OBJECTIVE

To evaluate the clinico-epidemiological profile, pattern of infections, feeding practices, socio-demographic risk factors and outcome of hospitalized children with moderate acute malnutrition (MAM) and severe acute malnutrition (SAM).

METHODS

Cases (children aged 1-60 mo with SAM or MAM) and controls (children with weight for height z score more than -1 SD) were recruited from November 2011 through July 2013. Overall, 126 cases and 126 controls were included.

RESULTS

Only 33 % of malnourished children (cases) were exclusively breast fed. Among controls, 71 % were exclusively breast fed for the first 6 mo after birth. Most cases had associated infections (p 0.004) and anemia (p < 0.001). ROC curve revealed 120 mm mid upper arm circumference (MUAC) as the best cut off for predicting SAM. Mothers' education, pre-lacteal feeds and co-morbidities were independent predictors of malnutrition (R(2) = 22.1 %) by logistic regression.

CONCLUSIONS

Though 11.5 cm MUAC has been mentioned by WHO as the cut off for identifying SAM, a higher cut off (12 cm) may be required to use it as a screening tool. Mothers' education, pre-lacteal feeds and co-morbidities were found to be independent determinants for malnutrition in the present patient population, indicating the need towards a targeted approach for modifying these factors.

Enteric pathogens of food sellers in rural Gambia with incidental finding of Myxobolus species (Protozoa: Myxozoa)

BACKGROUND

Ongoing surveillance of enteric pathogens of public health significance among casual food sellers is undertaken in many resource-limited countries. We report the results of a survey in Kiang West province, The Gambia, and provide an exemplar methodology for such surveys in resource-limited laboratories.

METHODS

Unpreserved, unrefrigerated stool samples were subjected to Salmonella, Shigella and agar plate culture for rhabditoid nematodes. Direct microscopy, formalin-ethyl acetate concentration and iron-hematoxylin staining was performed later, following preservation.

RESULTS

Of 128 specimens received, no Shigella spp. was recovered, while four serovars of non-typhoidal Salmonella enterica, including Chandans, were isolated. Pathogenic parasitic infections were Necator americanus 10/128 (7.8%), Strongyloides stercoralis 3/128 (2.8%), Blastocystis species 45/128 (35.1%), Entamoeba histolytica complex 19/128 (14.8%) and Giardia intestinalis 4/128 (3.1%). A single case each of Hymenolepis diminuta and S. mansoni infection were detected. In one participant, myxozoan spores identical to those of Myxobolus species were found.

CONCLUSIONS

Rare parasitoses and serovars of Salmonella enterica may occur relatively commonly in rural Africa. This paper describes intestinal pathogens found in a cohort of food sellers in such a setting. Furthermore, it describes two parasites rarely recovered from humans and demonstrates the need for methods other than microscopy to detect S. stercoralis infections.

Severe acute malnutrition and infection

Severe acute malnutrition (SAM) is associated with increased severity of common infectious diseases, and death amongst children with SAM is almost always as a result of infection. The diagnosis and management of infection are often different in malnourished versus well-nourished children. The objectives of this brief are to outline the evidence underpinning important practical questions relating to the management of infectious diseases in children with SAM and to highlight research gaps. Overall, the evidence base for many aspects covered in this brief is very poor. The brief addresses antimicrobials; antipyretics; tuberculosis; HIV; malaria; pneumonia; diarrhoea; sepsis; measles; urinary tract infection; nosocomial Infections; soil transmitted helminths; skin infections and pharmacology in the context of SAM. The brief is structured into sets of clinical questions, which we hope will maximise the relevance to contemporary practice.