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1.
Pharmacy (Basel) ; 12(2)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38668086

RESUMEN

Urinary tract infections (UTIs) are one of the most common infections and are frequently caused by Gram-negative organisms. The rise of resistant isolates has prompted evaluation of alternative therapies, including amoxicillin-clavulanate which has potent activity against Ambler class A enzymes. This study sought to evaluate clinical outcomes of patients with ceftriaxone non-susceptible UTIs receiving amoxicillin-clavulanate or standard of care (SOC). This was a single-center, retrospective, cohort study of adult patients with urinary tract infections caused by a ceftriaxone non-susceptible pathogen who received amoxicillin-clavulanate or SOC. The primary outcome was clinical failure at 90 days. Secondary outcomes included time to failure, isolation of a resistant organism, and hospital length of stay. Fifty-nine patients met study inclusion: 26 received amoxicillin/clavulanate and 33 received SOC. Amoxicillin-clavulanate recipients did not have higher failure rates compared to SOC recipients. For patients requiring hospital admission, hospital length of stay was numerically shorter with amoxicillin-clavulanate. The frequency of amoxicillin-clavulanate and carbapenem-resistant organisms did not differ significantly between groups. Amoxicillin-clavulanate may be a useful alternative therapy for the treatment of ceftriaxone non-susceptible Enterobacterales UTIs.

3.
Acad Emerg Med ; 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38450896

RESUMEN

BACKGROUND: Antimicrobial resistance among Enterobacterales continues to be a growing problem, particularly in those with urinary infections. Previous studies have demonstrated safety and efficacy with the use of single-dose aminoglycosides in uncomplicated cystitis. However, data in complicated infections are limited. Single-dose aminoglycosides may provide a convenient alternative for those with or at risk for resistant pathogens causing complicated urinary infections, especially when oral options are unavailable due to resistance, allergy, intolerance, or interactions with other medications. This study evaluated the safety and effectiveness of single-dose aminoglycosides in treatment of complicated cystitis in the emergency department (ED). METHODS: This was a multicenter, prospective study performed between July 2022 and March 2023 of patients who met criteria for complicated cystitis and were otherwise stable for discharge at an academic ED. Primary outcomes were clinical or microbiologic failure within 14 days of treatment. Safety was assessed by review of adverse events. Descriptive statistics were used. RESULTS: Thirteen patients were included. Complicating factors were male sex (n = 4), kidney stone (n = 2), urinary catheter (n = 6), recent urologic procedure (n = 1), urinary hardware (n = 1), antibiotic allergy precluding use of alternate oral options (n = 4), immunocompromised status (n = 2), and <1-year history of multidrug-resistant organisms on urine culture (n = 8). Eleven patients (85%) had positive urine cultures in the preceding 12 months with no oral antimicrobial option. Eight patients (62%) received amikacin (median dose 15 mg/kg), four patients (31%) received gentamicin (median dose 5 mg/kg), and one patient (8%) received tobramycin (5 mg/kg) for treatment. Ten patients (77%) reported resolved urinary symptoms after treatment and 11 patients (85%) reported no new urinary symptoms since discharge. No patient required hospital admission for treatment failure, and no adverse events were noted. CONCLUSIONS: Single-dose aminoglycosides appear to be a reasonably effective and safe treatment for complicated cystitis, which avoided hospital admission in this cohort.

5.
BMC Infect Dis ; 24(1): 127, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38267844

RESUMEN

BACKGROUND: Oritavancin, a long-acting lipoglycopeptide approved for use in acute bacterial skin and skin structure infections, has limited data evaluating use in serious infections due to Gram-positive organisms. We aimed to assess the effectiveness and safety of oritavancin for consolidative treatment of Gram-positive bloodstream infections (BSI), including infective endocarditis (IE). METHODS: We conducted a retrospective cohort study evaluating adult patients admitted to University of Colorado Hospital from March 2016 to January 2022 who received ≥ 1 oritavancin dose for treatment of Gram-positive BSI. Patients were excluded if the index culture was drawn at an outside facility or were > 89 years of age. The primary outcome was a 90-day composite failure (clinical or microbiological failure) in those with 90-day follow-up. Secondary outcomes included individual components of the primary outcome, acute kidney injury (AKI), infusion-related reactions (IRR), and institutional cost avoidance. RESULTS: Overall, 72 patients were included. Mean ± SD age was 54 ± 16 years, 61% were male, and 10% had IE. Organisms most commonly causing BSI were Staphylococcus aureus (68%, 17% methicillin-resistant), followed by Streptococcus spp. (26%), and Enterococcus spp. (10%). Patients received standard-of-care antibiotics before oritavancin for a median (IQR) of 11 (5-17) days. Composite failure in the clinically evaluable population (n = 64) at 90-days occurred in 14% and was composed of clinical and microbiological failure, which occurred in 14% and 5% of patients, respectively. Three patients (4%) experienced AKI after oritavancin, and two (3%) experienced an IRR. Oritavancin utilization resulted in earlier discharge for 94% of patients corresponding to an institutional cost-avoidance of $3,055,804 (mean $44,938/patient) from 1,102 hospital days saved (mean 16 days/patient). CONCLUSIONS: The use of oritavancin may be an effective sequential therapy for Gram-positive BSI to facilitate early discharge resulting in institutional cost avoidance.


Asunto(s)
Lesión Renal Aguda , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Endocarditis Bacteriana , Endocarditis , Vancomicina/análogos & derivados , Adulto , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Lipoglucopéptidos/uso terapéutico , Estudios Retrospectivos
6.
Ther Adv Infect Dis ; 11: 20499361231223889, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38249543

RESUMEN

Background: Severe gram-positive infections are frequent in people who inject drugs, and successful completion of treatment presents unique challenges in this population. Objectives: We aimed to evaluate the feasibility of a long-acting antibiotic, dalbavancin, as an alternative to standard-of-care antibiotics for severe infections due to vancomycin-susceptible pathogens requiring ⩾2 weeks of therapy. Design: We designed an investigator-initiated single-arm unblinded prospective cohort study to evaluate the safety and efficacy of an early switch to dalbavancin in two doses administered 1 week apart. Methods: We screened patients admitted with bloodstream infection, osteomyelitis, septic arthritis, infective endocarditis or deep abscesses, and comorbid substance use disorder (SUD) for eligibility. Consenting patients were switched to dalbavancin within 7 days from their index culture. They were monitored in the hospital for efficacy and safety of the treatment until the second dose of dalbavancin 7 days later and then discharged if stable. Study participants were evaluated with a decision support engine for a hypothetical appropriate level of care regarding their SUD after discharge. Their follow-up was planned for 12 months from the index culture, either in-person or via telehealth/telephone. Results: The enrollment was terminated early due to significant loss-to-follow-up. In all, 11 patients were enrolled, 4 completed 12 months of follow-up, 2 completed 8 months of follow-up, and 1 was seen once after discharge. The remaining five patients were lost to follow-up immediately after discharge. All 11 patients continued to improve after switching to dalbavancin between the first and second doses. There were two per-protocol failures of treatment. Dalbavancin was well tolerated, though some adverse events were reported. Conclusion: Dalbavancin may be a safe and effective alternative for an early switch in treating severe gram-positive infections. Trial registration: The trial was registered as NCT04847921 with clinicaltrials.gov.

7.
J Pediatr Urol ; 20(2): 200-210, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37788943

RESUMEN

INTRODUCTION AND BACKGROUND: Recent medical advances, including closure of myelomeningocele defects, shunting of hydrocephalus, and focusing on renal preservation have led to many individuals with spina bifida (SB) living into adulthood. This has led to more individuals with SB transitioning their care from pediatric-based to adult-based care models. OBJECTIVE: We seek to explore the process of transition, with a focus on difficulties in transitioning individuals with SB. Additionally, we explore new problems that arise during the period of transition related to sexual function and dysfunction. We also discuss some of the difficulties managing neurogenic bladder and the sequalae of their prior urologic surgeries. STUDY DESIGN: Each of the authors was asked to provide a summary, based on current literature, to highlight the challenges faced in their area of expertise. CONCLUSIONS: Transitioning care for individuals with SB is especially challenging due to associated neurocognitive deficits and neuropsychological functioning issues. Sexual function is an important component of transition that must be addressed in young adults with SB. Management of neurogenic bladder in adults with SB can be challenging due to the heterogeneity of the population and the sequelae of their prior urologic surgeries. The aim is to ensure that all individuals with SB receive appropriate, evidence-based care throughout their lifetime.

9.
J Surg Educ ; 80(5): 629-632, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36935296

RESUMEN

The Wellness-Inspired Resident Education (WIRE) curriculum is a resident-driven educational program consisting of six formal panels or lectures that are fully incorporated into the yearly resident didactic schedule, in addition to informal events and a resident wellness retreat. The curriculum promotes personal and professional wellness, enhances resident and department camaraderie, and provides opportunities to network with leaders in the field of plastic surgery. This paper provides the context which inspired the development of this curriculum, as well as key steps for successful implementation of wellness educational programming at any institution.


Asunto(s)
Agotamiento Profesional , Internado y Residencia , Humanos , Educación de Postgrado en Medicina , Curriculum , Educación en Salud , Promoción de la Salud
10.
J Burn Care Res ; 44(1): 203-206, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36173707

RESUMEN

Patients with burn injuries are at high risk for infection as well as altered antimicrobial pharmacokinetics. Patients suffering from a burn injury, generally encompassing a total body surface area (TBSA) ≥ 20%, have been cited as at risk for augmented renal clearance (ARC). Our case report describes an obese patient with 3.2% TBSA partial thickness burns who suffered from burn wound cellulitis with Pseudomonas aeruginosa. Measured CLcr documented the presence of ARC, and 22.5 grams daily continuous infusion of piperacillin-tazobactam was initiated. Therapeutic monitoring of piperacillin at steady state was 78 mcg/mL, achieving the prespecified goal piperacillin concentration of 100% 4-times the minimum inhibitory concentration assuming MIC for susceptible P. aeruginosa at 16/4 mcg/mL per Clinical Laboratory Standards Institute. Available literature suggests younger critically ill patients with lower organ failure scores, and for a burn injury, a higher percentage of TBSA, are most likely to exhibit ARC which does not entirely align with the characteristics of our patient. In addition, piperacillin-tazobactam has been associated with altered pharmacokinetics in ARC, burn, and obese populations, demonstrating failure to meet target attainment with standard doses. We suggest a continuous infusion of piperacillin-tazobactam be used when ARC is identified. This case report describes the unique findings of ARC in a non-critically ill burn patient and rationalizes the need for further prospective research to classify incidence, risk factors, and appropriate antimicrobial regimens for burn patients with ARC.


Asunto(s)
Quemaduras , Piperacilina , Humanos , Piperacilina/farmacocinética , Tazobactam , Antibacterianos , Quemaduras/complicaciones , Quemaduras/tratamiento farmacológico , Combinación Piperacilina y Tazobactam , Enfermedad Crítica/terapia , Pruebas de Sensibilidad Microbiana
11.
Open Forum Infect Dis ; 9(7): ofac335, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35899276

RESUMEN

Background: Dalbavancin (DAL) is a long-acting lipoglycopeptide with activity against Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA). This study investigates DAL as sequential therapy in S. aureus bloodstream infections (BSIs). Methods: We conducted a retrospective cohort study from 2014 to 2021 comparing sequential DAL with standard-of-care therapy (SoC) for S. aureus BSI. The primary outcome was 90-day clinical failure (90-day all-cause mortality or 90-day recurrence). Secondary outcomes were incidence of acute kidney injury, creatinine phosphokinase elevations, catheter-related thrombosis, and hospital-acquired infections. Analyses were adjusted using inverse probability of treatment weighting (IPTW). Results: Overall, 225 patients (45 DAL, 180 SoC) were included. DAL patients had a higher incidence of community-acquired infection and persons who use drugs; SoC patients had more comorbidities and a longer duration of bacteremia. MRSA incidence was similar between the DAL and SoC groups. The median length of stay was 16 days among DAL recipients compared with 24 days among SoC recipients. Central catheter placement was 17.8% compared with 57.2% in the SoC group. Ninety-day clinical failure occurred in 13.3% and 18.3% of participants in the DAL and SOC groups, respectively. In IPTW-adjusted analysis, sequential DAL was not associated with 90-day clinical failure (adjusted odds ratio, 0.94; 95% CI, 0.333-2.32). Conclusions: This study provides preliminary evidence that select patients with S. aureus BSI treated with sequential DAL have similar clinical failure rates, with significant reductions in catheter placement and hospital length of stay compared with SoC. Further prospective evaluation is needed.

12.
Open Forum Infect Dis ; 9(6): ofac028, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35615295

RESUMEN

Tedizolid has activity against Gram-positive pathogens as well as Mycobacterium spp and Nocardia spp. Real-world evidence supporting long-term tolerability and clinical success of tedizolid is lacking. Prolonged tedizolid therapy (median, 188 days; interquartile range, 62-493 days) appeared to be well tolerated in 37 patients (8.1% experienced adverse effect leading to discontinuation). Clinical success was 81.3% in those evaluated.

13.
Int J Pharm ; 620: 121753, 2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35439574

RESUMEN

Permeation of a weak acid (benzoic acid) and a weak base (propranolol) in various stages of ionization through human skin in vitro was measured from 0 to 72 h following solvent deposition of radiolabeled doses ranging from 11 to 11,000 nmol/cm2 and 1.93-1930 nmol/cm2, respectively. For the twenty combinations tested for each compound, mean permeation into the receptor fluid over 72 h ranged from 1.5 to 40.7 percent of dose for benzoic acid and 1.3-35.5 percent of dose for propranolol. For all but the lowest doses, permeation increased with increasing fraction of nonionized permeant in the dose solution. Generally, this trend became stronger as the dose increased. Recovery of radioactivity averaged 94.3 ± 5.5% for propranolol and was independent of ionization state and dose. Recovery of radioactivity for benzoic acid ranged from 40 to >100%, increasing with fraction nonionized and with dose. These effects can be qualitatively explained in terms of the low permeability of ionized species through stratum corneum, the volatility of free benzoic acid, and a buffer capacity of the stratum corneum deposition region on the order of 10-20 nmol/cm2.


Asunto(s)
Sales (Química) , Absorción Cutánea , Ácido Benzoico , Electrólitos , Humanos , Permeabilidad , Propranolol , Piel , Solventes
14.
J Pharm Sci ; 111(3): 727-733, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34600943

RESUMEN

A quantitative understanding of the dose dependence of topical delivery is important to cosmetic and dermatological product development and to risk assessment for hazardous chemicals contacting the skin. Despite considerable research, predictive capability in this area remains limited. To this end we conducted an experimental skin absorption study of two closely related skin care agents, niacinamide (nicotinamide, NA) and methyl nicotinate (MN), and analyzed the results quantitatively using a transient diffusion model described separately (Yu et al. submitted for publication). Radiolabeled test compounds were solvent-deposited onto ex vivo human skin mounted in Franz diffusion cells over a dose range exceeding 4.5 orders of magnitude, and permeation was measured over a 1-4 day period. At low doses, the permeation rate of NA was approximately 60-fold lower than that of its lower melting, more lipophilic analog, MN; at high doses an even greater difference was observed. The difference can be qualitatively explained based on higher lipid solubility and lower crystallinity of MN relative to NA. Dissolution-limited mass transfer through a lipid layer at the SC surface is suggested. Relevance of the results to practical skin care formulations was confirmed by a parallel study of NA in an o/w emulsion.


Asunto(s)
Niacinamida , Absorción Cutánea , Administración Cutánea , Humanos , Lípidos/química , Niacinamida/química , Ácidos Nicotínicos , Permeabilidad , Piel/metabolismo , Solventes/química
15.
Clin Infect Dis ; 74(9): 1572-1578, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-34665248

RESUMEN

BACKGROUND: Bezlotoxumab (BEZ) is a monoclonal antibody used to prevent recurrent Clostridioides difficile infection (rCDI). This study investigates BEZ effectiveness in relation to rCDI and patient-specific risk factors in a real-world setting. METHODS: A matched, retrospective cohort study was conducted from 2015 to 2019 to compare BEZ to historical standard of care (SoC) therapy with vancomycin or fidaxomicin. The primary outcome was incidence of 90-day rCDI. Secondary outcomes were incidence of all-cause hospital readmission and all-cause mortality at 90 days, infusion-related reactions, and incidence of heart failure exacerbation. Baseline confounding was addressed using inverse probability of treatment weighting (IPTW). RESULTS: Overall, 107 participants were included (54 BEZ and 53 SoC). Mean number of prior CDI episodes was 2, median number of risk factors for rCDI was 4, and 28% of participants had severe CDI. Incidence of 90-day rCDI was 11% BEZ vs 43% SoC (P = < .001) and 90-day all-cause readmission was 40% BEZ vs 64% SoC (P = .011). In IPTW-adjusted analyses, BEZ was associated with significantly reduced odds of rCDI (odds ratio [OR], 0.14 [95% confidence interval {CI}: .05-.41]) and all-cause readmission (OR, 0.36 [95% CI: .16-.81]). No safety signals were detected with BEZ use. CONCLUSIONS: BEZ is effective for the prevention of rCDI and reduction in all-cause hospital readmission for patients at high risk for recurrence, supporting current guideline recommendations.


Asunto(s)
Clostridioides difficile , Infecciones por Clostridium , Antibacterianos/efectos adversos , Anticuerpos Monoclonales/efectos adversos , Anticuerpos ampliamente neutralizantes , Infecciones por Clostridium/epidemiología , Infecciones por Clostridium/prevención & control , Humanos , Recurrencia , Estudios Retrospectivos , Nivel de Atención
16.
Clin Pharmacokinet ; 61(3): 363-374, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34931283

RESUMEN

Dalbavancin is a synthetic lipoglycopeptide that exerts its antimicrobial activity through two distinct modes of action, inhibition of cell wall synthesis and an anchoring mechanism. Compared with previous glycopeptide antibiotics, dalbavancin demonstrates improved antibacterial potency against Gram-positive organisms and a long half-life of approximately 1 week, which is longer in tissues (e.g., skin, bone) than plasma. These factors facilitated the development of single-dose or once-weekly dosing regimens to treat acute bacterial skin and skin structure infections (ABSSSI). Dalbavancin exhibits dose-proportional pharmacokinetics and is highly protein bound (93%). Despite being highly protein bound, it has a steady-state volume of distribution >10 L and distributes widely into the skin, bone, peritoneal space, and epithelial lining fluid, but not cerebrospinal fluid. Dalbavancin elimination occurs via a combination of renal (approximately 45%) and non-renal clearance, with dose adjustments recommended only in patients with a creatinine clearance <30 mL/min not receiving any form of dialysis. The established pharmacokinetic/pharmacodynamic index associated with bacterial kill is free area under the concentration-time curve over the minimum inhibitory concentration (fAUC/MIC), with a goal 24-h fAUC/MIC of at least 27.1 for Staphylococcus aureus infections. Recent data suggest usefulness in the treatment of infections beyond ABSSSI, with convenient dosing and redosing strategies for complicated infections requiring extended treatment durations. Additional studies are needed to confirm these preliminary findings.


Asunto(s)
Antibacterianos , Teicoplanina , Humanos , Lipoglucopéptidos , Pruebas de Sensibilidad Microbiana , Teicoplanina/análogos & derivados , Teicoplanina/farmacología
17.
PLoS Biol ; 19(11): e3001441, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34723965

RESUMEN

Open access, high-resolution soil property maps have been created for Africa at 30 m resolution, using machine learning trained on over 100,000 analysed soil samples. Combined with other field-level information, iSDAsoil enables the possibility of site-specific agronomy advisory for smallholder farmers.


Asunto(s)
Suelo , África , Geografía , Concentración de Iones de Hidrógeno
18.
Open Forum Infect Dis ; 8(7): ofab294, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34262988

RESUMEN

BACKGROUND: Bezlotoxumab significantly reduces the incidence of recurrent Clostridioides difficile infection (CDI); however, limited data are available in solid organ transplant (SOT) and hematopoietic cell transplant (HCT) recipients. METHODS: We conducted a single-center retrospective analysis comparing recurrent CDI in SOT and HCT recipients receiving standard of care alone (oral vancomycin, fidaxomicin, or metronidazole) or bezlotoxumab plus standard of care. The primary outcome was 90-day incidence of recurrent CDI, and secondary outcomes included 90-day hospital readmission, mortality, and incidence of heart failure exacerbation. RESULTS: Overall, 94 patients received bezlotoxumab plus standard of care (n = 38) or standard of care alone (n = 56). The mean age was 53 years; patients had a median of 3 prior Clostridioides difficile episodes and 4 risk factors for recurrent infection. Most patients were SOT recipients (76%), with median time to index CDI occurring 2.7 years after transplantation. Ninety-day recurrent CDI occurred in 16% (6/38) in the bezlotoxumab cohort compared to 29% (16/56) in the standard of care cohort (P = .13). Multivariable regression revealed that bezlotoxumab was associated with significantly lower odds of 90-day recurrent CDI (odds ratio, 0.28 [95% confidence interval, .08-.91]). There were no differences in secondary outcomes, and no heart failure exacerbations were observed. CONCLUSIONS: In a cohort of primarily SOT recipients, bezlotoxumab was well tolerated and associated with lower odds of recurrent CDI at 90 days. Larger, prospective trials are needed to confirm these findings among SOT and HCT populations.

19.
Expert Opin Pharmacother ; 22(10): 1355-1371, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33878996

RESUMEN

Introduction: Invasive fungal infections (IFIs) remain a significant cause of morbidity and mortality despite significant advancements in currently available therapy. With a flush pipeline of investigational antifungals, the clinician must identify appropriate roles of currently available therapies, potential advantages of emerging antifungals, and shortcomings in the evolving clinical evidence.Areas covered: Standard and developing treatment approaches for IFIs with currently available antifungals are summarized with a focus on invasive candidiasis and invasive aspergillosis. Emerging investigational antifungals are discussed in depth, including mechanisms of action, fungal activity, clinical evidence, and ongoing research. An opinion on the impact and potential role of therapy for emerging antifungals of interest is also provided.Expert opinion: Despite advances and clinical studies optimizing antifungal use, current therapies fall short in preventing IFI morbidity and mortality. Further optimization of currently available antifungals may improve outcomes; however, novel agents are required for historically difficult-to-treat infections, transitions to oral treatment, minimizing adverse drug effects, decreasing drug interactions, and ultimately improving patient quality of life. Emerging antifungals may positively revolutionize the treatment of IFIs.


Asunto(s)
Aspergilosis , Candidiasis , Infecciones Fúngicas Invasoras , Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Candidiasis/tratamiento farmacológico , Humanos , Infecciones Fúngicas Invasoras/tratamiento farmacológico , Calidad de Vida
20.
Sci Rep ; 11(1): 6130, 2021 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-33731749

RESUMEN

Soil property and class maps for the continent of Africa were so far only available at very generalised scales, with many countries not mapped at all. Thanks to an increasing quantity and availability of soil samples collected at field point locations by various government and/or NGO funded projects, it is now possible to produce detailed pan-African maps of soil nutrients, including micro-nutrients at fine spatial resolutions. In this paper we describe production of a 30 m resolution Soil Information System of the African continent using, to date, the most comprehensive compilation of soil samples ([Formula: see text]) and Earth Observation data. We produced predictions for soil pH, organic carbon (C) and total nitrogen (N), total carbon, effective Cation Exchange Capacity (eCEC), extractable-phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), sodium (Na), iron (Fe), zinc (Zn)-silt, clay and sand, stone content, bulk density and depth to bedrock, at three depths (0, 20 and 50 cm) and using 2-scale 3D Ensemble Machine Learning framework implemented in the mlr (Machine Learning in R) package. As covariate layers we used 250 m resolution (MODIS, PROBA-V and SM2RAIN products), and 30 m resolution (Sentinel-2, Landsat and DTM derivatives) images. Our fivefold spatial Cross-Validation results showed varying accuracy levels ranging from the best performing soil pH (CCC = 0.900) to more poorly predictable extractable phosphorus (CCC = 0.654) and sulphur (CCC = 0.708) and depth to bedrock. Sentinel-2 bands SWIR (B11, B12), NIR (B09, B8A), Landsat SWIR bands, and vertical depth derived from 30 m resolution DTM, were the overall most important 30 m resolution covariates. Climatic data images-SM2RAIN, bioclimatic variables and MODIS Land Surface Temperature-however, remained as the overall most important variables for predicting soil chemical variables at continental scale. This publicly available 30-m Soil Information System of Africa aims at supporting numerous applications, including soil and fertilizer policies and investments, agronomic advice to close yield gaps, environmental programs, or targeting of nutrition interventions.

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