Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
BMC Infect Dis ; 23(1): 135, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36882712

RESUMEN

BACKGROUND: Fluoroquinolones have been, and continue to be, routinely used for treatment of many bacterial infections. In recent years, most parts of the world have reported an increasing trend of fluoroquinolone resistant (FQR) Gram-negative bacteria. METHODS: A cross-sectional study was conducted between March 2017 and July 2018 among children admitted due to fever to referral hospitals in Dar es Salaam, Tanzania. Rectal swabs were used to screen for carriage of extended-spectrum ß-lactamase-producing Enterobacterales (ESBL-PE). ESBL-PE isolates were tested for quinolone resistance by disk diffusion method. Randomly selected fluroquinolone resistant isolates were characterized by using whole genome sequencing. RESULTS: A total of 142 ESBL-PE archived isolates were tested for fluoroquinolone resistance. Overall phenotypic resistance to ciprofloxacin, levofloxacin and moxifloxacin was found in 68% (97/142). The highest resistance rate was seen among Citrobacter spp. (100%, 5/5), followed by Klebsiella. pneumoniae (76.1%; 35/46), Escherichia coli (65.6%; 42/64) and Enterobacter spp. (31.9%; 15/47). Whole genome sequencing (WGS) was performed on 42 fluoroquinolone resistant-ESBL producing isolates and revealed that 38/42; or 90.5%, of the isolates carried one or more plasmid mediated quinolone resistance (PMQR) genes. The most frequent PMQR genes were aac(6')-lb-cr (74%; 31/42), followed by qnrB1 (40%; 17/42), oqx, qnrB6 and qnS1. Chromosomal mutations in gyrA, parC and parE were detected among 19/42 isolates, and all were in E. coli. Most of the E. coli isolates (17/20) had high MIC values of > 32 µg/ml for fluoroquinolones. In these strains, multiple chromosomal mutations were detected, and all except three strains had additional PMQR genes. Sequence types, ST131 and ST617 predominated among E. coli isolates, while ST607 was more common out of 12 sequence types detected among the K. pneumoniae. Fluoroquinolone resistance genes were mostly associated with the IncF plasmids. CONCLUSION: The ESBL-PE isolates showed high rates of phenotypic resistance towards fluoroquinolones likely mediated by both chromosomal mutations and PMQR genes. Chromosomal mutations with or without the presence of PMQR were associated with high MIC values in these bacteria strains. We also found a diversity of PMQR genes, sequence types, virulence genes, and plasmid located antimicrobial resistance (AMR) genes towards other antimicrobial agents.


Asunto(s)
Fluoroquinolonas , Quinolonas , Niño , Humanos , Fluoroquinolonas/farmacología , Tanzanía/epidemiología , Estudios Transversales , Escherichia coli/genética , Quinolonas/farmacología
2.
Ann Clin Microbiol Antimicrob ; 22(1): 16, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36803640

RESUMEN

BACKGROUND: Over one million yearly deaths are attributable to Streptococcus pneumoniae and people living with HIV are particularly vulnerable. Emerging penicillin non-susceptible Streptococcus pneumoniae (PNSP) challenges therapy of pneumococcal disease. The aim of this study was to determine the mechanisms of antibiotic resistance among PNSP isolates by next generation sequencing. METHODS: We assessed 26 PNSP isolates obtained from the nasopharynx from 537 healthy human immunodeficiency virus (HIV) infected adults in Dar es Salaam, Tanzania, participating in the randomized clinical trial CoTrimResist (ClinicalTrials.gov identifier: NCT03087890, registered on 23rd March, 2017). Next generation whole genome sequencing on the Illumina platform was used to identify mechanisms of resistance to antibiotics among PNSP. RESULTS: Fifty percent (13/26) of PNSP were resistant to erythromycin, of these 54% (7/13) and 46% (6/13) had MLSB phenotype and M phenotype respectively. All erythromycin resistant PNSP carried macrolide resistance genes; six isolates had mef(A)-msr(D), five isolates had both erm(B) and mef(A)-msr(D) while two isolates carried erm(B) alone. Isolates harboring the erm(B) gene had increased MIC (> 256 µg/mL) towards macrolides, compared to isolates without erm(B) gene (MIC 4-12 µg/mL) p < 0.001. Using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines, the prevalence of azithromycin resistance was overestimated compared to genetic correlates. Tetracycline resistance was detected in 13/26 (50%) of PNSP and all the 13 isolates harbored the tet(M) gene. All isolates carrying the tet(M) gene and 11/13 isolates with macrolide resistance genes were associated with the mobile genetic element Tn6009 transposon family. Of 26 PNSP isolates, serotype 3 was the most common (6/26), and sequence type ST271 accounted for 15% (4/26). Serotypes 3 and 19 displayed high-level macrolide resistance and frequently carried both macrolide and tetracycline resistance genes. CONCLUSION: The erm(B) and mef(A)-msr(D) were common genes conferring resistance to MLSB in PNSP. Resistance to tetracycline was conferred by the tet(M) gene. Resistance genes were associated with the Tn6009 transposon.


Asunto(s)
Infecciones por VIH , Infecciones Neumocócicas , Adulto , Humanos , Antibacterianos/farmacología , Streptococcus pneumoniae/genética , Macrólidos/farmacología , Penicilinas , Resistencia a la Tetraciclina/genética , Tanzanía , Farmacorresistencia Bacteriana/genética , Eritromicina , Infecciones por VIH/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana
3.
Curr Microbiol ; 80(5): 148, 2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-36964831

RESUMEN

The spreading of multidrug resistance (MDR) strains in the hospital settings via contaminated surfaces have been increasingly reported where Gram-negative bacteria have been implicated in causing most nosocomial infections. This study aimed to determine the rate of contamination with multi-resistant gram-negative bacteria in the hospital environment. A cross-sectional study was conducted at Muhimbili National Hospital paediatric department, between July and August 2020. Non-repetitive surface swab samples were collected from predefined surfaces and medical device surfaces, and cultured on MacConkey agar with and without antibiotics. Isolates were identified using biochemical test and tested for antibiotic susceptibility using the Kirby-Bauer disk diffusion method. The rate of hospital contamination with Gram-negative bacteria across the Pediatrics units was 30%, with a high rate observed in oncology units (34.8%) and the malnutrition/diarrhoea ward (32.1%). Sink/washing basin had the highest frequency of bacterial contamination (74.2%). We observed a high rate of ESBL (32.5%), with Acinetobacter baumannii, Klebsiella pneumoniae, and E. coli being the predominant ESBL-producing Gram-negative bacteria, while carbapenemase-producing Gram-negative bacteria was detected at 22.8%. Highest resistance rates (63-100%) were observed against ceftriaxone and trimethoprim-sulfamethoxazole. Up to 51% of the Gram-negative bacteria showed resistant to meropenem. MDR strains were detected in 61.4% of Gram-negative bacteria isolated. In conclusion, we observed a high rate of MDR bacteria contaminating hospital surfaces. The higher rate of MDR calls for a need to strengthen infectious prevention control measures, including cleaning practices in the hospital environment, to reduce the risk of transmission of resistant strains to patients and healthcare workers.


Asunto(s)
Antibacterianos , Escherichia coli , Humanos , Niño , Centros de Atención Terciaria , Tanzanía/epidemiología , Estudios Transversales , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacterias Gramnegativas , Farmacorresistencia Bacteriana Múltiple , Bacterias
4.
Eur J Clin Microbiol Infect Dis ; 40(7): 1477-1485, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33586013

RESUMEN

Difficult-to-treat infections caused by methicillin-resistant Staphylococcus aureus (MRSA) are of concern in people living with HIV infection as they are more vulnerable to infection. We aimed to identify molecular characteristics of MRSA colonizing newly diagnosed HIV-infected adults in Tanzania. Individuals newly diagnosed with HIV infection were recruited in Dar es Salaam, Tanzania, from April 2017 to May 2018, as part of the randomized clinical trial CoTrimResist ( ClinicalTrials.gov identifier: NCT03087890). Nasal/nasopharyngeal isolates of Staphylococcus aureus were susceptibility tested by disk diffusion method, and cefoxitin-resistant isolates were characterized by short-reads whole genome sequencing. Four percent (22/537) of patients carried MRSA in the nose/nasopharynx. MRSA isolates were frequently resistant towards gentamicin (95%), ciprofloxacin (91%), and erythromycin (82%) but less often towards trimethoprim-sulfamethoxazole (9%). Seventy-three percent had inducible clindamycin resistance. Erythromycin-resistant isolates harbored ermC (15/18) and LmrS (3/18) resistance genes. Ciprofloxacin resistance was mediated by mutations of the quinolone resistance-determining region (QRDR) sequence in the gyrA (S84L) and parC (S80Y) genes. All isolates belonged to the CC8 and ST8-SCCmecIV MRSA clone. Ninety-five percent of the MRSA isolates were spa-type t1476, and one exhibited spa-type t064. All isolates were negative for Panton-Valentine leucocidin (PVL) and arginine catabolic mobile element (ACME) type 1. All ST8-SCCmecIV-spa-t1476 MRSA clones from Tanzania were unrelated to the globally successful USA300 clone. Carriage of ST8 MRSA (non-USA300) was common among newly diagnosed HIV-infected adults in Tanzania. Frequent co-resistance to non-beta lactam antibiotics limits therapeutic options when infection occurs.


Asunto(s)
Toxinas Bacterianas , Exotoxinas , Infecciones por VIH/complicaciones , Leucocidinas , Staphylococcus aureus Resistente a Meticilina/clasificación , Infecciones Estafilocócicas/complicaciones , Infecciones Estafilocócicas/microbiología , Infecciones Comunitarias Adquiridas , Genotipo , Infecciones por VIH/epidemiología , VIH-1 , Humanos , Resistencia a la Meticilina , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/metabolismo , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Filogenia , Infecciones Estafilocócicas/epidemiología , Tanzanía/epidemiología , Virulencia
5.
BMC Infect Dis ; 20(1): 557, 2020 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-32736605

RESUMEN

BACKGROUND: Multi-drug resistance pathogens such as Extended-Spectrum Beta-Lactamase (ESBL) producing Enterobacteriaceae (ESBL-PE) are of great global health concern, since they are associated with increased morbidity and mortality. Even in the absence of infections caused by these pathogens, colonization is a great threat and can lead to cross transfer among hospitalized patients. To date data on carriage of these pathogens is still limited in Tanzania. Therefore, this study aimed to determine ESBL-PE fecal carriage rate and associated factors among hospitalized patients at Referral hospitals in Dar es Salaam. METHODS: This was a cross sectional study conducted from May to July 2017 among patients admitted in three referral hospitals in Dar es Salaam, Tanzania. Rectal swabs were collected and screened for ESBL production using MacConkey agar supplemented with Ceftazidime 2 µg/ml. Phenotypic confirmation of ESBL-PE was done by double disk diffusion method. Statistical analysis was performed using Statistical Package for Social Sciences (SPPS) software version 20. RESULTS: Of the 196 enrolled participants, 59.7% (117/196) were confirmed to carry ESBL-PE. Diarrheic patients (57/79) had statistically significant high prevalence of ESBL colonization compared to those without diarrhea (60/117) (p = 0.01). A total of 131 ESBL-PE were isolated from 117 patients, whereby, Escherichia coli accounted for 68.7%, Klebsiella pneumoniae 28.2% and Citrobacter species 0.8%. ESBL-PE carriage was significantly higher in patients with diarrhea compared to those without diarrhea (72% vs 53.1%, p = 0.01). Recent antibiotic use was independently associated with carriage of ESBL-PE (aOR 14.65, 95%CI 3.07-69.88, p = 0.01). CONCLUSIONS: High prevalence of fecal carriage of ESBL-PE was observed in patients admitted in tertiary hospitals in Dar es Salaam, Tanzania. The use of antibiotics was associated with carriage of ESBL producers among the study population.


Asunto(s)
Infecciones por Enterobacteriaceae/microbiología , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/metabolismo , Heces/microbiología , beta-Lactamasas/biosíntesis , Adolescente , Adulto , Antibacterianos/uso terapéutico , Ceftazidima , Estudios Transversales , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Infecciones por Enterobacteriaceae/epidemiología , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Prevalencia , Derivación y Consulta , Tanzanía/epidemiología , Centros de Atención Terciaria/estadística & datos numéricos , Adulto Joven
6.
BMC Infect Dis ; 17(1): 117, 2017 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-28152988

RESUMEN

BACKGROUND: Bacterial diarrhoeal disease is among the most common causes of mortality and morbidity in children 0-59 months at the University Teaching Hospital in Lusaka, Zambia. However, most cases are treated empirically without the knowledge of aetiological agents or antimicrobial susceptibility patterns. The aim of this study was, therefore, to identify bacterial causes of diarrhoea and determine their antimicrobial susceptibility patterns in stool specimens obtained from the children at the hospital. METHODS: This hospital-based cross-sectional study involved children aged 0-59 months presenting with diarrhoea at paediatrics wards at the University Teaching Hospital in Lusaka, Zambia, from January to May 2016. Stool samples were cultured on standard media for enteropathogenic bacteria, and identified further by biochemical tests. Multiplex polymerase chain reaction was used for characterization of diarrhoeagenic Escherichia coli strains. Antimicrobial susceptibility testing was performed on antibiotics that are commonly prescribed at the hospital using the Kirby-Bauer disc diffusion method, which was performed using the Clinical Laboratory Standards International guidelines. RESULTS: Of the 271 stool samples analysed Vibrio cholerae 01 subtype and Ogawa serotype was the most commonly detected pathogen (40.8%), followed by Salmonella species (25.5%), diarrhoeagenic Escherichia coli (18%), Shigella species (14.4%) and Campylobacter species (3.5%). The majority of the bacterial pathogens were resistant to two or more drugs tested, with ampicillin and co-trimoxazole being the most ineffective drugs. All diarrhoeagenic Escherichia coli isolates were extended spectrum ß-lactamase producers. CONCLUSION: Five different groups of bacterial pathogens were isolated from the stool specimens, and the majority of these organisms were multidrug resistant. These data calls for urgent revision of the current empiric treatment of diarrhoea in children using ampicillin and co-trimoxazole, and emphasizes the need for continuous antimicrobial surveillance as well as the implementation of prevention programmes for childhood diarrhoea.


Asunto(s)
Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones por Campylobacter/microbiología , Diarrea/microbiología , Farmacorresistencia Bacteriana/efectos de los fármacos , Disentería Bacilar/microbiología , Infecciones por Escherichia coli/microbiología , Campylobacter/aislamiento & purificación , Infecciones por Campylobacter/tratamiento farmacológico , Infecciones por Campylobacter/epidemiología , Preescolar , Estudios Transversales , Diarrea/tratamiento farmacológico , Diarrea/epidemiología , Disentería Bacilar/tratamiento farmacológico , Disentería Bacilar/epidemiología , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/epidemiología , Femenino , Hospitales Universitarios , Humanos , Lactante , Recién Nacido , Masculino , Pruebas de Sensibilidad Microbiana , Prevalencia , Estudios Prospectivos , Shigella/aislamiento & purificación , Zambia/epidemiología
7.
BMC Infect Dis ; 17(1): 282, 2017 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-28415986

RESUMEN

BACKGROUND: The spread of Extended Spectrum ß-lactamases (ESBLs) among Enterobacteriaceae and other Gram-Negative pathogens in the community and hospitals represents a major challenge to combat infections. We conducted a study to assess the prevalence and genetic makeup of ESBL-type resistance in bacterial isolates causing community- and hospital-acquired urinary tract infections. METHODS: A total of 172 isolates of Enterobacteriaceae were collected in Dar es Salaam, Tanzania, from patients who met criteria of community and hospital-acquired urinary tract infections. We used E-test ESBL strips to test for ESBL-phenotype and PCR and sequencing for detection of ESBL genes. RESULTS: Overall 23.8% (41/172) of all isolates were ESBL-producers. ESBL-producers were more frequently isolated from hospital-acquired infections (32%, 27/84 than from community-acquired infections (16%, 14/88, p < 0.05). ESBL-producers showed high rate of resistance to ciprofloxacin (85.5%), doxycycline (90.2%), gentamicin (80.5%), nalidixic acid (84.5%), and trimethoprim-sulfamethoxazole (85.4%). Furthermore, 95% of ESBL-producers were multi-drug resistant compared to 69% of non-ESBL-producers (p < 0.05). The distribution of ESBL genes were as follows: 29/32 (90.6%) bla CTX-M-15, two bla SHV-12, and one had both bla CTX-M-15 and bla SHV-12. Of 29 isolates carrying bla CTX-M-15, 69% (20/29) and 31% (9/29) were hospital and community, respectively. Bla SHV-12 genotypes were only detected in hospital-acquired infections. CONCLUSION: bla CTX-M-15 is a predominant gene conferring ESBL-production in Enterobacteriaceae causing both hospital- and community-acquired infections in Tanzania.


Asunto(s)
Técnicas de Tipificación Bacteriana/métodos , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Infecciones por Enterobacteriaceae/epidemiología , Enterobacteriaceae/genética , Infecciones Urinarias/epidemiología , Infecciones Urinarias/microbiología , beta-Lactamasas/genética , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Farmacorresistencia Bacteriana/genética , Resistencia a Múltiples Medicamentos/genética , Enterobacteriaceae/aislamiento & purificación , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Infecciones por Enterobacteriaceae/microbiología , Femenino , Hospitales , Humanos , Pruebas de Sensibilidad Microbiana , Reacción en Cadena de la Polimerasa , Tanzanía/epidemiología , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Infecciones Urinarias/tratamiento farmacológico , beta-Lactamasas/análisis
8.
BMC Pregnancy Childbirth ; 17(1): 109, 2017 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-28388879

RESUMEN

BACKGROUND: Hepatitis B virus (HBV) and Human immunodeficiency virus (HIV) infection in pregnancy is associated with direct effect of pregnancy and potential viral transmission from mother to newborn. In Tanzania very little in known on prevalence of HBV infection and their associated factors among pregnant women in lower health facilities. The main objective of the study was to determine the prevalence of HBsAg, HIV and HBV-HIV co-infection among pregnant women attending antenatal clinics in Dar es Salaam. METHODS: This cross sectional study was conducted in three Temeke municipal health-care facilities between May 2014 and June 2014. A total of 249 pregnant women attending antenatal clinic (ANC) were consecutively enrolled in the study. A data collection tool was used to extract socio-demographic characteristics from ANC card. Commercial ARCHITECT® ci4100™ was used to assess HBsAg status and liver function (Alanine amino-transferase (ALAT). HIV status was determined by anti-HIV antibody test. RESULTS: Of 249 pregnant women enrolled the median age was 25 years (IQR 22-30) and most of them were married (72.4%). The overall prevalence of HBsAg and HIV were 8.03% (95% CI: 5.0-12.1%) and 17.2% (95% CI: 12.8-22.5%), respectively. HBV/HIV co-infection rate was 2.8% (95% CI; 1.3-5.4%). HBsAg positive rate was significantly high in women who were HIV positive (p < 0.05). Being employed /student were less associated with HBV infection (aOR 0.35, 95% CI 0.13-0.95). Only 3 (15%) of pregnant women with HBsAg positive had abnormal ALAT. CONCLUSIONS: High prevalence of HBV and HIV infections among pregnant women were reported in this setting thus calls for the national expansion of the integration of prevention of mother-to-child transmission (PMTCT) services for HBV infection.


Asunto(s)
Coinfección/epidemiología , Infecciones por VIH/epidemiología , Hepatitis B/epidemiología , Complicaciones Infecciosas del Embarazo/epidemiología , Adolescente , Adulto , Instituciones de Atención Ambulatoria/estadística & datos numéricos , Coinfección/virología , Estudios Transversales , Femenino , VIH , Infecciones por VIH/virología , Hepatitis B/virología , Virus de la Hepatitis B , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/virología , Atención Prenatal/estadística & datos numéricos , Estudios Seroepidemiológicos , Tanzanía/epidemiología , Adulto Joven
9.
BMC Public Health ; 15: 501, 2015 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-25994129

RESUMEN

BACKGROUND: The occurrence of HIV-1 and syphilis infections during pregnancy poses major health risks to the foetus due to mother-to-child transmission. We conducted surveillance of HIV and syphilis infections among pregnant women attending antenatal clinics (ANCs) in Mainland Tanzania in 2011. METHODS: This surveillance was carried out in 133 ANCs selected from 21 regions in Tanzania. In each region, six ANC sites were selected, with urban, semi-urban, and rural areas contributing two each. All pregnant women who were attending selected sentinel ANC sites for the first time at any pregnancy between September and December 2011 were enrolled. Serial ELISA assays were performed to detect HIV infection in an unlinked anonymous manner using dried blood spot (DBS) after routine syphilis testing. Data analysis was conducted using Stata v.12 software. RESULTS: A total of 39,698 pregnant women representing 2.4 % of all pregnant women (1.68 million) attending ANCs in the Mainland Tanzania were enrolled. The overall HIV prevalence was found to be 5.6 % (95 % CI: 5.4-5.8 %). The risk for HIV infection was significantly higher among women aged 25-34 (cOR = 1.97, 95 % CI: 1.79-2.16; p < 0.05), older than 35 years (cOR = 1.88, 95 % CI: 1.62-2.17; p < 0.05) and those having 1-2 and 3-4 previous pregnancies. HIV infection was less prevalent among women attending rural ANC clinics (cOR = 0.46, 95 % CI 0.4-0.52; p < 0.05). The overall syphilis prevalence was 2.5 % (95 % CI: 2.3, 3.6). The risk for syphilis infection was significantly higher among women attending semi-urban and rural clinics and those having 3-4, and 5 previous pregnancies (p < 0.05). Marital status and level of education were not statistically significant with either of the two infections. HIV and syphilis co-infections occurred in 109 of 38,928 (0.3 %). CONCLUSION: The overall prevalence of HIV infection (5.6 %) and syphilis (2.5 %) found among pregnant women attending ANC clinics in Tanzania calls for further strengthening of current intervention measures, which include scaling up the integration of prevention of mother to child transmission (PMTCT) services in Reproductive and Child Health (RCH) clinics.


Asunto(s)
Infecciones por VIH/epidemiología , Complicaciones Infecciosas del Embarazo/epidemiología , Sífilis/epidemiología , Adolescente , Adulto , Factores de Edad , Femenino , Humanos , Estado Civil , Paridad , Embarazo , Atención Prenatal , Prevalencia , Población Rural , Tanzanía/epidemiología , Adulto Joven
10.
PLoS One ; 19(4): e0302076, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38625965

RESUMEN

BACKGROUND: Polymicrobial bloodstream infections (BSI) are difficult to treat since empiric antibiotics treatment are frequently less effective against multiple pathogens. The study aimed to compare outcomes in patients with polymicrobial and monomicrobial BSIs. METHODS: The study was a retrospective case-control design conducted at Muhimbili National Hospital for data processed between July 2021 and June 2022. Cases were patients with polymicrobial BSI, and controls had monomicrobial BSI. Each case was matched to three controls by age, admitting ward, and duration of admission. Logistic regression was performed to determine independent risk factors for in-hospital and 30-day mortality. RESULTS: Fifty patients with polymicrobial BSI and 150 with monomicrobial BSI were compared: the two arms had no significant differences in sex and comorbidities. The most frequent bacteria in polymicrobial BSI were Klebsiella pneumoniae 17% (17/100) and Enterobacter species 15% (15/100). In monomicrobial BSI, S. aureus 17.33% (26/150), Klebsiella pneumoniae 16.67% (25/150), and Acinetobacter species 15% (15/150) were more prevalent. Overall, isolates were frequently resistant to multiple antibiotics tested, and 52% (130/250) were multidrug resistance. The 30-day and in-hospital mortality were 33.5% (67/200) and 36% (72/200), respectively. On multivariable analysis, polymicrobial BSIs were independent risk factors for both in-hospital mortality (aOR 2.37, 95%CI 1.20-4.69, p = 0.01) and 30-day mortality (aOR 2.05, 95%CI 1.03-4.08), p = 0.04). In sub-analyses involving only neonates, polymicrobial BSI was an independent risk factor for both 30-day mortality (aOR 3.13, 95%CI 1.07-9.10, p = 0.04) and in-hospital mortality (aOR 5.08, 95%CI 1.60-16.14, p = 0.006). Overall, the median length of hospital stay post-BSIs was numerically longer in patients with polymicrobial BSIs. CONCLUSION: Overall, polymicrobial BSI was a significant risk for mortality. Patients with polymicrobial BSI stay longer at the hospital than those with monomicrobial BSI. These findings call for clinicians to be more aggressive in managing polymicrobial BSI.


Asunto(s)
Bacteriemia , Sepsis , Recién Nacido , Humanos , Estudios de Casos y Controles , Estudios Retrospectivos , Bacteriemia/microbiología , Tanzanía/epidemiología , Staphylococcus aureus , Sepsis/microbiología , Factores de Riesgo , Hospitales , Antibacterianos/uso terapéutico
11.
BMJ Open ; 14(10): e085580, 2024 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-39461858

RESUMEN

OBJECTIVES: The objectives are to determine the prevalence of urinary tract infection (UTI) and associated factors among patients diagnosed with benign prostatic hyperplasia and prostate cancer. DESIGN: Hospital-based cross-sectional study. SETTINGS: Urology clinic and urology ward at Muhimbili National Hospital, which is the main tertiary hospital in Tanzania's largest city. PARTICIPANTS: Patients with benign prostate hyperplasia and prostate cancer presenting with genitourinary symptoms. MAIN OUTCOME MEASURE: The primary outcome was the occurrence of UTI and factors associated with UTI in patients with benign prostatic hyperplasia and prostate cancer. RESULTS: 402 participants were enrolled, with a median age of 68 years and IQR of 61-75 years. The proportion of UTI was 46.5% (95% CI 41.56% to 51.53%). UTI was more prevalent among inpatients, patients with indwelling urinary catheters, patients with prostate size>80 cm3 and those with residual urine volume of >100 mL. In multivariate analysis, age>60 years (adjusted OR (aOR)=2.0, 95% CI 1.13 to 3.55, p=0.018), post-void residual urine volume>100 mL (aOR 1.32, 95% CI 0.67 to 2.59 p=0.001), patient with incomplete bladder emptying (aOR=2.57, 95% CI 1.44 to 4.59, p=0.001) and prolonged catheter duration (aOR=1.24, 95% CI 1.11 to 1.38, p=0.005) were significantly associated with UTI. CONCLUSION: Almost half of the patients with an enlarged prostate and genitourinary symptoms had a laboratory-confirmed UTI. The risk of UTI increases with age, incomplete bladder emptying and increased duration of catheterisation. A 1-day increase in the duration of catheterisation increased the risk of UTI by 24%.


Asunto(s)
Hiperplasia Prostática , Centros de Atención Terciaria , Infecciones Urinarias , Humanos , Masculino , Tanzanía/epidemiología , Estudios Transversales , Infecciones Urinarias/epidemiología , Hiperplasia Prostática/epidemiología , Hiperplasia Prostática/complicaciones , Persona de Mediana Edad , Anciano , Prevalencia , Factores de Riesgo , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/complicaciones , Próstata/patología
12.
PLoS Negl Trop Dis ; 18(4): e0012132, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38630840

RESUMEN

BACKGROUND: Typhoid fever is a common cause of febrile illness in low- and middle-income countries. While multidrug-resistant (MDR) Salmonella Typhi (S. Typhi) has spread globally, fluoroquinolone resistance has mainly affected Asia. METHODS: Consecutively, 1038 blood cultures were obtained from patients of all age groups with fever and/or suspicion of serious systemic infection admitted at Mnazi Mmoja Hospital, Zanzibar in 2015-2016. S. Typhi were analyzed with antimicrobial susceptibility testing and with short read (61 strains) and long read (9 strains) whole genome sequencing, including three S. Typhi strains isolated in a pilot study 2012-2013. RESULTS: Sixty-three S. Typhi isolates (98%) were MDR carrying blaTEM-1B, sul1 and sul2, dfrA7 and catA1 genes. Low-level ciprofloxacin resistance was detected in 69% (43/62), with a single gyrase mutation gyrA-D87G in 41 strains, and a single gyrA-S83F mutation in the non-MDR strain. All isolates were susceptible to ceftriaxone and azithromycin. All MDR isolates belonged to genotype 4.3.1 lineage I (4.3.1.1), with the antimicrobial resistance determinants located on a composite transposon integrated into the chromosome. Phylogenetically, the MDR subgroup with ciprofloxacin resistance clusters together with two external isolates. CONCLUSIONS: We report a high rate of MDR and low-level ciprofloxacin resistant S. Typhi circulating in Zanzibar, belonging to genotype 4.3.1.1, which is widespread in Southeast Asia and African countries and associated with low-level ciprofloxacin resistance. Few therapeutic options are available for treatment of typhoid fever in the study setting. Surveillance of the prevalence, spread and antimicrobial susceptibility of S. Typhi can guide treatment and control efforts.


Asunto(s)
Antibacterianos , Ciprofloxacina , Farmacorresistencia Bacteriana Múltiple , Genotipo , Pruebas de Sensibilidad Microbiana , Salmonella typhi , Fiebre Tifoidea , Humanos , Salmonella typhi/genética , Salmonella typhi/efectos de los fármacos , Salmonella typhi/aislamiento & purificación , Salmonella typhi/clasificación , Ciprofloxacina/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Antibacterianos/farmacología , Fiebre Tifoidea/microbiología , Fiebre Tifoidea/epidemiología , Tanzanía/epidemiología , Adolescente , Masculino , Niño , Adulto , Adulto Joven , Femenino , Preescolar , Secuenciación Completa del Genoma , Persona de Mediana Edad , Lactante , Anciano
13.
Antimicrob Resist Infect Control ; 12(1): 112, 2023 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-37817204

RESUMEN

BACKGROUND: In Tanzania, data on antibiotic use at the patient level is scarce, and intervention measures to optimize antibiotic use and reduce antimicrobial resistance are rarely performed. OBJECTIVES: To describe antibiotic use at Muhimbili National Hospital. METHODS: This was a point prevalence survey on antibiotic use conducted at Muhimbili National Hospital in August-September 2022. The World Health Organization point prevalence survey data collection tool was used to collect patients' information from the files. All patients admitted to the wards on the day of the survey were included. RESULTS: Overall, 47% (185/397) of admitted patients were on at least one antibiotic during the survey. All antibiotics prescribed were for empirical treatment and guideline compliance was low, at 45%. Of 185 patients who received antibiotics, the most common indication was community acquired infection (55%) and 36% had no documentation of the reasons for prescribing antibiotics. Almost 75% of the antibiotics were administered parenterally, with only 2% switching to oral route. Microbiological tests were performed in only 9 (5%) patients out of 185 and results were available for only one patient. Of all participants, 52% received two or more antibiotic in combination, with the combination ceftriaxone-metronidazole being most frequently prescribed, followed by the combination of ampicillin, cloxacillin, and gentamicin. For individual antibiotics, ceftriaxone was the most frequently prescribed antibiotic accounting for 28% (79/283), followed by metronidazole (24%) and amoxicillin-clavulanic acid (11%). CONCLUSION: The findings of a high prevalence of antibiotic use, inadequate use of bacterial culture, and frequent empiric antibiotic treatment suggests the need for strengthening diagnostic and antimicrobial stewardship programs. Furthermore, this study has identified areas for quality improvement, including education programs focusing on prescription practice.


Asunto(s)
Antibacterianos , Ceftriaxona , Humanos , Antibacterianos/uso terapéutico , Prevalencia , Centros de Atención Terciaria , Metronidazol , Tanzanía/epidemiología
14.
BMJ Open ; 13(4): e070003, 2023 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-37085309

RESUMEN

OBJECTIVES: This study aimed to determine the oral carriage prevalence of Candida species and identify factors associated with the carriage of Candida species among patients with cancer on treatment. DESIGN: A hospital-based cross-sectional study. SETTING: The study was conducted at a tertiary-level cancer hospital Ocean Road Cancer Institute (ORCI), Dar es Salaam, Tanzania. PARTICIPANTS: We enrolled 196 participants who consented to join the study. Oral swabs were collected from all participants and inoculated onto Sabouraud dextrose agar supplemented with 50 mg/mL gentamicin and 50 mg/mL chloramphenicol, and chromogenic agar for phenotypic identification of Candida species. PRIMARY OUTCOME: The study reported the high prevalence of oral carriage of Candida species among patients with cancer on treatment at the tertiary-level cancer hospital in Dar es Salaam, Tanzania. RESULTS: A total of 196 participants were enrolled in the study. The overall oral carriage of Candida species was 37.8% (74/196). The prevalence was higher among patients undergoing chemotherapy and radiotherapy (44.4%) than those in monotherapy (13.3% chemotherapy, 20% radiotherapy). Candida krusei was the most common isolated species, 48.6% (36/74). Head and neck (adjusted OR (aOR) 15.09, 95% CI 3.05 to 74.59, p=0.00), gastrointestinal (aOR 14.14, 95% CI 2.25 to 88.63, p=0.00) malignancies and diabetes (aOR 3.18, 95% CI 1.03 to 9.77, p=0.04) were factors independently associated with oral carriage of Candida species. CONCLUSION: The oral carriage of Candida species among patients with cancer receiving treatment at ORCI is high, mainly due to C. krusei species. This is alarming since C. krusei has intrinsic resistance to fluconazole, a common antifungal agent used to manage adult fungal infections. Therefore, efforts should be put into conducting regular check-ups for such opportunistic pathogens as they can lead to subsequent infections. Furthermore, studies conducted to determine the antifungal profile of the causative agents are warranted since different causative agents might have different profiles.


Asunto(s)
Antifúngicos , Neoplasias , Adulto , Humanos , Estudios Transversales , Tanzanía/epidemiología , Agar , Antifúngicos/uso terapéutico , Fluconazol/farmacología , Fluconazol/uso terapéutico , Candida , Neoplasias/tratamiento farmacológico , Neoplasias/epidemiología , Pruebas de Sensibilidad Microbiana
15.
BMJ Open ; 13(4): e068359, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-37012005

RESUMEN

OBJECTIVES: To determine the aetiological pathogens causing ear infections and their antimicrobial susceptibility patterns among patients with ear complaints at a tertiary hospital in Dar es Salaam. DESIGN: Hospital-based cross-sectional study. SETTINGS: Otorhinolaryngology clinic at Muhimbili National Hospital, Dar es Salaam, Tanzania. PARTICIPANTS: Patients presenting with signs and symptoms of ear infection. MAIN OUTCOME MEASURE: Bacteria and fungi isolated from ear swab specimens of patients presenting with signs and symptoms of ear infection; and antimicrobial susceptibility patterns of isolated bacteria. RESULTS: Two hundred and fifty-five participants were enrolled, with a median age of 31 years and an IQR of 15-49. Otitis externa was the predominant type of ear infection, accounting for 45.1%. We observed positive bacteria culture in 53.3% of study participants, in which 41% of isolates were obtained from patients with chronic suppurative otitis media. Moreover, Staphylococcus aureus (27.3%) and Pseudomonas aeruginosa (24.2%) were the most frequently isolated bacteria, while Candida spp, 12 (63.8%) and Aspergillus spp, 9 (36.2%) were the only isolated fungi. Furthermore, we report that 93% of isolated Enterobacterales were resistant to amoxicillin/clavulanic acid, and 73% were resistant to ceftazidime. In addition, we detected 34.4% extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-PE) and 44.4% methicillin-resistance S. aureus (MRSA). We also found that 22% of the bacteria isolates were resistant to ciprofloxacin, a primary topical antibiotic used in managing ear infections. CONCLUSIONS: The findings from this study reveal that the leading aetiological agent of ear infection is bacteria. Furthermore, our findings show a significant proportion of ESBL-PE and MRSA-causing ear infections. Hence, detecting multidrug-resistant bacteria is crucial to improving ear infection management.


Asunto(s)
Otitis , Otolaringología , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Centros de Atención Terciaria , Estudios Transversales , Staphylococcus aureus , Tanzanía/epidemiología , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacterias , Otitis/tratamiento farmacológico
16.
Infect Prev Pract ; 4(2): 100212, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35495173

RESUMEN

Background: Multi-drug resistant (MDR) bacteria pose a major global threat to public-health and are of particular concern to hospitalized intensive care unit (ICU) patients. This study aimed at addressing the burden of MDR and the associated factors at admission to ICU. Methods: This was a cross-sectional study conducted at the ICU of a tertiary hospital in Tanzania. Rectal and anterior nares swabs were collected within 48 hours of ICU admission to screen for extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-PE) and meticillin-resistant Staphylococcus aureus (MRSA), respectively. Results: The proportion of fecal carriage for ESBL-PE at admission to ICU was 54.54% (95% CI, 47.52-61.39), and nasal carriage for MRSA was 9.32% (95%CI, 5.67-14.93). The nasal MRSA colonization (OR = 1.52) and fecal carriage for ESBL-PE (OR=1.38) were more likely in participants who had received antibiotics before ICU admission than not, but association was not statistically significant. Hospitalization for ≥2 days (OR=1.18) was associated with fecal carriage of ESBL-PE, though not statistically significant. Overall, 66% and 73.5% of patients received antibiotics before and upon admission to ICU, respectively. Ceftriaxone, metronidazole and meropenem were commonly prescribed antibiotics. More than 84% of Enterobacterales were resistant to ciprofloxacin and trimethoprim-sulfamethoxazole, and 2.90% were resistant to meropenem. MRSA isolates showed a high rate of resistance to gentamicin and erythromycin. Conclusion: MDR bacteria are common in patients admitted to ICU. To reduce the risk associated with MDR, we recommend use of simple screening methods to screen for MDR at ICU admission as part of infection control and prevention.

17.
East Afr Health Res J ; 6(1): 113-118, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36424947

RESUMEN

Background: Surgical Site Infection (SSI) is one of the major hospital acquired infections, highly associated with prolonged hospitalisation, morbidity and mortality. In open urological surgeries, little is known on magnitude and factors associated with development of SSI. Methods and Materials: The intervention was a cross-sectional prospective observational study performed between August 2015 and March 2016 at Muhimbili National hospital (MNH), Dar es Salaam, Tanzania. Patients who underwent open urological surgery at MNH during the study period and met inclusion criteria were consecutively enrolled, and followed up for 30 days. Patients' and operative characteristics were recorded using standard structured questionnaires. Wound/pus swabs were collected from patients with clinical evidence of SSI for bacteriological processing. Data analysis was performed using SPSS version 20. Results: Of 182 patients who underwent open urological surgery, 22% (40/182) developed SSI. Pre-operative urinary tract infection (aOR 9.73, 95%CI 3.93-24.09, p<.001) and contaminated wound class (aOR 24.997, 95%CI 2.58-242.42, p = .005) were independent predictors for development of SSI. Shaving within 30 hrs before surgical procedure was found to be protective for developing SSI (aOR 0.26, 95%CI 0.09-0.79, p=.02). Escherichia coli (20/40) was the most predominant pathogen in SSI followed by Klebsiella pneumoniae (7/40) and S. aureus (6/40). Gram-negative bacteria were highly resistant to ceftriaxone, gentamicin, amoxicillin-clavulanic acid and trimethoprimsulfamethoxazole. Conclusion: Surgical Site Infection was high in open urological interventions. Pre-operative urinary tract infection and contaminated wound class predicted SSI. Bacteria causing SSI were highly resistant to commonly used antibiotics.

18.
Afr Health Sci ; 22(4): 470-476, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37092062

RESUMEN

Background: Toxoplasmosis in HIV-infected women of child-bearing age (HIV-WCB) increases the risk for congenital toxoplasmosis, leading to many complications. However, its magnitude is unknown in this population. Objectives: The study aimed to determine the prevalence and factors associated with toxoplasmosis among HIV-WCB. Methods: This was a cross-sectional study conducted from July to August 2020 among HIV- WCB attending care and treatment clinic (CTC) at Muhimbili National Hospital and Mnazi Mmoja hospital. Questionnaire and TORCH rapid test were used to obtain data and serological testing respectively. Data analysis was done using statistical package for social sciences (SPSS) version 20. Results: Overall, 29.7% of the study participants were positive for anti-T. gondii IgG, whereas none tested positive for IgM. Multivariate analysis showed that the probability of being infected with T. gondii increased by 57.1% for participants who consumed raw vegetables (p=0.005, aOR=0.43, 95%CI = 1.24-8.77). Other common risk factors such as undercooked meat consumption, source of drinking water, and cat ownership at home showed no association. Conclusion: A high number of HIV-WCB have not developed immunity to T. gondii in the study area. Introduction of routine screening during antenatal visits for pregnant women and further epidemiological studies are warranted in the country.


Asunto(s)
Infecciones por VIH , Toxoplasma , Toxoplasmosis , Femenino , Embarazo , Humanos , Estudios Seroepidemiológicos , Estudios Transversales , Tanzanía/epidemiología , Anticuerpos Antiprotozoarios , Toxoplasmosis/complicaciones , Toxoplasmosis/epidemiología , Factores de Riesgo , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología
19.
J Med Microbiol ; 71(2)2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35225760

RESUMEN

Introduction. Carbapenem-resistant members of the family Enterobacteriaceae are emerging as a global public-health threat and cause substantial challenges in clinical practice.Gap Statement. There is a need for increased and continued genomic surveillance of antimicrobial resistance genes globally in order to detect outbreaks and dissemination of clinically important resistance genes and their associated mobile genetic elements in human pathogens.Aim. To describe the resistance mechanisms of carbapenem-resistant Escherichia coli.Methods. Rectal swabs from neonates and newly diagnosed human immunodeficiency virus (HIV) infected adults were collected between April 2017 and May 2018 and screened for faecal carriage of carbapenamases and OXA-48 producing members of the family Enterobacteriaceae. Bacterial isolates were identified using matrix assisted laser desorption ionization time of flight mass spectrometry. Antimicrobial susceptibility testing was performed by E-test. Whole genomes of carbapenem-resistant E. coli were investigated using a hybrid assembly of Illumina and Oxford Nanopore Technologies sequencing reads.Results. Three carbapenem-resistant E. coli were detected, two from neonates and one from an HIV infected adult. All three isolates carried bla NDM-5. Two E. coli from neonates belonged to ST167 and bla NDM-5 co-existed with bla CTX-M-15 and bla OXA-01, and all were carried on IncFIA type plasmids. The E. coli from the HIV infected adult belonged to ST2083, and carried bla NDM-5 on an IncX3 type plasmid and bla CMY-42 on an IncI type plasmid. All bla NDM-5 carrying plasmids contained conjugation related genes. In addition, E. coli from the HIV infected adult carried three more plasmid types; IncFIA, IncFIB and Col(BS512). One E. coli from a neonate also carried one extra plasmid Col(BS512). All three E. coli harboured resistance genes to fluoroquinolone, aminoglycosides, sulfamethoxazole, trimethoprim, macrolides and tetracycline, carried on the IncFIA type plasmid. Furthermore, E. coli from the neonates carried a chloramphenicol resistance gene (catB3), also on the IncFIA plasmid. All three isolates were susceptible to colistin.Conclusion. This is the first report, to our knowledge, from Tanzania detecting bla NDM-5 producing E. coli. The carbapenemase gene was carried on an IncFIA and IncX3 type plasmids. Our findings highlight the urgent need for a robust antimicrobial resistance (AMR) surveillance system to monitor and rapidly report on the incidence and spread of emerging resistant bacteria in Tanzania.


Asunto(s)
Infecciones por Escherichia coli , Escherichia coli , Infecciones por VIH , Adulto , Antibacterianos , Carbapenémicos , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/epidemiología , Infecciones por VIH/complicaciones , Humanos , Recién Nacido , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Tanzanía/epidemiología , beta-Lactamasas/clasificación , beta-Lactamasas/genética
20.
J Glob Antimicrob Resist ; 30: 107-114, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35667646

RESUMEN

OBJECTIVES: Gastrointestinal colonization of extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-PE) is of concern because prior colonization increases risk for subsequent infections. To date, the link between ESBL-PE faecal carriage and the risk of subsequent ESBL-PE infection has not been well established, and information on carriage of such pathogens among children with invasive infections such as bloodstream infections (BSI) remains to be explored worldwide. METHODS: This cross-sectional study was conducted among children under the age of 5 years admitted for febrile illness in Dar es Salaam, Tanzania, between March 2017 and July 2018. We used rectal swabs to screen for ESBL-PE using selective media, ChromID ESBL. Bacterial isolates were identified by MALDI-TOF. Blood cultures were drawn from all children. Antimicrobial susceptibility testing was done using a disk diffusion method. ESBL alleles were identified by real-time PCR and sequencing. RESULTS: The overall prevalence of ESBL-PE carriage was 56% (112/200) and was highest among children 4 to 6 months old (17/21, 81%) (P = 0.05). Children with BSI had high ESBL-PE carriage (78.4%) compared to those without BSI (53.1%) (P = 0.02; aOR 3.4, 95% confidence interval 1.20-9.58). The most common isolate was E. coli (64/112, 45%). Sixteen pairs of ESBL-PE isolates (from the gut and from blood) had a similar antimicrobial susceptibility profile. We detected blaCTX-M gene in 97% of all phenotypically detected ESBL-PE; among those, blaCTX-M-15 was dominant (99%). CONCLUSION: We report a high prevalence of ESBL-PE faecal carriage among children with BSI in Tanzania. Colonization of ESBL-PE was a risk factor for ESBL-BSI.


Asunto(s)
Infecciones por Enterobacteriaceae , Enterobacteriaceae , Fiebre , beta-Lactamasas , Antiinfecciosos/farmacología , Niño , Preescolar , Estudios Transversales , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/enzimología , Enterobacteriaceae/aislamiento & purificación , Infecciones por Enterobacteriaceae/epidemiología , Infecciones por Enterobacteriaceae/microbiología , Femenino , Fiebre/microbiología , Humanos , Lactante , Masculino , Tanzanía/epidemiología , beta-Lactamasas/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA