Fiebre tifoidea: una etiología poco frecuente de síndrome febril prolongado en pediatría / Typhoid fever: a rare etiology of prolonged febrile illness in pediatrics / Febre tifoide: uma etiología rara de síndrome febril prolongada em pediatría

Introducción: Las infecciones representan la etiología más frecuente del síndrome febril prolongado (SFP). Si bien las fiebres entéricas constituyen una causa posible, en Uruguay su prevalencia ha disminuido significativamente con la mejora de las condiciones socio sanitarias. Objetivo: Comunicar el caso de un adolescente con una etiología actualmente excepcional de SFP. Caso clínico 14 años, sano, zona suburbana. Comienza 2 semanas previo al ingreso con dolor en hemiabdomen superior. Agrega cefalea holocraneana leve y vómitos ocasionales. 5 días previos al ingreso fiebre 40°C axilar, un pico diario, sin otra sintomatología. Tránsito digestivo bajo y urinario normal. Examen físico: lúcido, buen aspecto general, abdomen doloroso a la palpación profunda en epigastrio. Sin irritación peritoneal. Resto normal. Analítica: Leucocitos 5200mm3, Proteína C reactiva 71.4mg/dL, hemocultivo sin desarrollo. Ecografía abdominal, radiografía de tórax y ecocardiograma normales. Serologías para Virus Epstein Barr, Citomegalovirus, y Bartonella henselae negativas. Orina normal, urocultivo sin desarrollo. Persiste con fiebre, agrega exantema macropapular evanescente en tronco, sin otros síntomas. Al 7° día de internación nuevo hemocultivo: Salmonella Typhi sensible a ampicilina que recibe por 14 días. Buena evolución. Discusión: La fiebre tifoidea es una enfermedad infectocontagiosa, aguda, potencialmente mortal. Las condiciones socioeconómicas son determinantes en su transmisión. La sensibilidad del hemocultivo es mayor durante la primera semana de enfermedad, por lo que en ocasiones es necesario reiterarlo. Sus manifestaciones clínicas inespecíficas y la baja incidencia hacen que esta etiología no sea habitualmente sospechada en nuestro medio. Por tanto, es importante aumentar el índice de sospecha y considerar entre los diagnósticos diferenciales de SFP esta etiología.

Introduction: Infections are the most frequent etiology of prolonged febrile illness (PFI). Although enteric fevers are a possible cause, their prevalence has significantly diminished in Uruguay, due to improved socio-sanitary conditions. Objective: To communicate the case of an adolescent with a currently exceptional etiology of PFI. Clinical case: 14 years old, healthy, suburban area. Two days prior to admission the patient has pain in upper hemi abdomen. Adds mild holocranial headache and occasional vomiting. 5 days prior to admission axilary temperature of 40°C, one daily peak, without other symptoms. Normal lower digestive and urinary transit. Physical examination: lucid, good general aspect, pain at deep palpation in epigastrium. No peritoneal irritation. Rest is normal. Laboratory: leukocytes 5200 mm3, C-reactive protein 71.4mg/dL, blood culture shows no growth. Abdominal sonogram, thoracic X-ray and echocardiogram are normal. Negative serology for Epstein Barr Virus, Cytomegalovirus and Bartonella henselae. Normal urine, urine culture with no growth. Fever persists, adds evanescent macropapular exanthema in on the trunk, without other symptoms. On the 7th day in hospital a new blood culture shows Salmonella Typhi sensitive to ampicillin, which he receives for 14 days. Good evolution. Discussion: Typhoid fever is an acute, life-threatening, infectious disease. Socioeconomic conditions are determinant in its transmission. Blood culture sensitivity is greater during the first week of the disease, that is why it must occasionally be repeated. Its unspecific clinical manifestations and low incidence make this etiology not be usually suspected in our surroundings. It is therefore important to increase our suspicion and to consider it amongst differential diagnosis in PFI.

Introdução: As infecções representam a etiologia mais frequente da síndrome febril prolongada (SFP). Embora as febres entéricas sejam uma causa possível, no Uruguai sua prevalência diminuiu significativamente com a melhoria das condições sociossanitárias. Objetivo: Relatar o caso de um adolescente com etiologia atualmente excepcional de SFP. Caso clínico 14 anos, saudável, zona suburbana. Começa 2 semanas antes da admissão com dor no abdome superior. Adiciona dor de cabeça holocraniana leve e vômitos ocasionais. 5 dias antes da admissão febre 40°C axilar, pico diário, sem outros sintomas. Trânsito digestivo inferior e trânsito urinário normais. Exame físico: lúcido, bom aspecto geral, abdome doloroso à palpação profunda no epigástrio. Sem irritação peritoneal. Resto normal. Análise: Leucócitos 5200mm3, proteína C reativa 71,4mg/dL, hemocultura sem desenvolvimento. Ultrassonografia abdominal, radiografia de tórax e ecocardiograma foram normais. As sorologias para vírus Epstein Barr, Citomegalovírus e Bartonella henselae foram negativas. Urina normal, urocultura sem desenvolvimento. Persiste com febre, acrescenta erupção macropapular evanescente no tronco, sem outros sintomas. No 7º dia de internação, nova hemocultura: Salmonella Typhi sensível à ampicilina, que recebeu por 14 dias. Boa evolução. Discussão: A febre tifóide é uma doença infecciosa aguda, potencialmente fatal. As condições socioeconômicas são decisivas na sua transmissão. A sensibilidade da hemocultura é maior durante a primeira semana da doença, por isso às vezes é necessário repeti-la. Suas manifestações clínicas inespecíficas e baixa incidência fazem com que essa etiologia não seja usualmente suspeitada em nosso meio. Portanto, é importante aumentar o índice de suspeição e considerar essa etiologia entre os diagnósticos diferenciais da SFP.

[Suppurative Thrombophlebitis of the Posterior Neck Caused by Streptococcus constellatus: A Case Report and Literature Review].

We report a rare case of suppurative thrombophlebitis of the posterior neck caused by Streptococcus constellatus. A 69-year-old female patient was admitted to the hospital with neck pain and fever, which had persisted for 16 days prior to hospitalization. On day 1 (day of admission), blood cultures (later identifying S. constellatus) were performed, and ceftriaxone (CTRX) IV (2 g SID) was started. On day 3, suppurative thrombophlebitis of the posterior neck was diagnosed by CT scan. The antimicrobials were changed from CTRX to ampicillin/sulbactam IV (12 g QID) to guard against the possibility of complicated infection with Fusobacterium spp. or Prevotella spp. On day 17, a CT scan revealed that the thrombus remained. Therefore, oral edoxaban (30 mg SID) was started. On day 27, the patient was discharged after her medication was changed to oral amoxicillin/clavulanate (1500 mg/375 mg TID). On day 33, the amoxicillin/clavulanate was changed to oral cefaclor (1500 mg TID) and edoxaban was discontinued due to itching. On day 45, the course of cefaclor was completed. The patient went on to follow an uneventful course with no relapses or complications for two years since the conclusion of treatment. These results suggest that when a patient presents with persistent neck pain accompanied by fever, suppurative thrombophlebitis of the posterior neck should be considered. In antimicrobial therapy, the treatment could be switched from intravenous to oral. In addition, direct-acting oral anticoagulants may be an alternative to other forms of anticoagulants.

Mobility of ß-lactam resistance under ampicillin treatment in gut microbiota suffering from pre-disturbance.

Ingestion of food- or waterborne antibiotic-resistant bacteria may lead to dissemination of antibiotic resistance genes (ARGs) in the gut microbiota. The gut microbiota often suffers from various disturbances. It is not clear whether and how disturbed microbiota may affect ARG mobility under antibiotic treatments. For proof of concept, in the presence or absence of streptomycin pre-treatment, mice were inoculated orally with a ß-lactam-susceptible Salmonella enterica serovar Heidelberg clinical isolate (recipient) and a ß-lactam resistant Escherichia coli O80:H26 isolate (donor) carrying a blaCMY-2 gene on an IncI2 plasmid. Immediately following inoculation, mice were treated with or without ampicillin in drinking water for 7 days. Faeces were sampled, donor, recipient and transconjugant were enumerated, blaCMY-2 abundance was determined by quantitative PCR, faecal microbial community composition was determined by 16S rRNA amplicon sequencing and cecal samples were observed histologically for evidence of inflammation. In faeces of mice that received streptomycin pre-treatment, the donor abundance remained high, and the abundance of S. Heidelberg transconjugant and the relative abundance of Enterobacteriaceae increased significantly during the ampicillin treatment. Co-blooming of the donor, transconjugant and commensal Enterobacteriaceae in the inflamed intestine promoted significantly (P<0.05) higher and possibly wider dissemination of the blaCMY-2 gene in the gut microbiota of mice that received the combination of streptomycin pre-treatment and ampicillin treatment (Str-Amp) compared to the other mice. Following cessation of the ampicillin treatment, faecal shedding of S. Heidelberg transconjugant persisted much longer from mice in the Str-Amp group compared to the other mice. In addition, only mice in the Str-Amp group shed a commensal E. coli O2:H6 transconjugant, which carries three copies of the blaCMY-2 gene, one on the IncI2 plasmid and two on the chromosome. The findings highlight the significance of pre-existing gut microbiota for ARG dissemination and persistence during and following antibiotic treatments of infectious diseases.

Knowledge, attitudes and practices of animal farm owners/workers on antibiotic use and resistance in Amhara region, north western Ethiopia.

Inappropriate use of antibiotics in animal and human plays a role in the emergence and spread of bacteria resistant to antibiotics which threatens human health significantly. Although extensive use of these antibiotics could contribute to the development of drug resistance, information on the knowledge, attitude and practice of antimicrobial resistance and use among animal farm owners/workers in north western Ethiopia is rare. The objective of the present study was to assess knowledge, attitude and practice of animal farm owner/workers towards antibiotic resistance and use in Amhara regional state north western Ethiopia. A cross sectional study was conducted in selected cities of Amhara regional state from January to February, 2020. Data was collected from 91 participants using structured questionnaire and analyzed using SPSSS version 23. The results showed that 96.7% of respondents gave antibiotics to treat their livestock from different sources. Most of the respondents bought their antibiotics from private pharmacies without prescription and the most frequently mentioned antibiotics used to treat animal diseases was tetracycline (76.9%), followed by ampicillin (72.5%). Although, 90.1% of the animal farm owners heard about antibiotics and antibiotic resistance from different sources, they did not know the factors contributing to the transmission of resistant bacteria to humans and the impact of antibiotic resistance on human and animals' health. Using the mean score 4.44 ± 0.15 as the cut-off, half of the animal farm owners/workers had good knowledge about antimicrobial resistance and use. 52.5% of animal farm owners/workers had positive attitudes towards wise antibiotic use and resistance with a mean score of 28.4 ± 0.5. However, 52.75% participants had poor practice with the mean score of practice 4.95 ± 0.17. Better knowledge, positive attitudes and better practices on antibiotic use and resistance were associated with farm owners/workers who engaged in higher education. Although poor awareness on antimicrobial resistance was perceived by 76.9% of respondents as very important factors that contribute to increasing antibiotic resistance, increasing the use of complementary treatments was perceived by the majority of respondents as very important strategies that contribute to reduce antibiotic use and resistance. The current study disclosed that there is low level of awareness among animal farm owners about the correct use of antibiotics and resistance. It is necessary to raise awareness, develop and implement interventions to reduce antimicrobial use and antibiotic resistance in the study area.

Brain abscess due to listeria monocytogenes: A case report and literature review.

RATIONALE: Listeria monocytogenes infective encephalitis is a rare phenomenon, which is more common in people with changed eating habits and immunodeficiency. To the best of our knowledge, listeria brain abscess is even more rare. In this case report, we summarized the clinical characteristics of listeria brain abscess, in order to explore the diagnosis and treatment of Listeria brain abscess, and raise awareness and attention to the disease. PATIENT CONCERNS: A 64-years-old female patient presented to our institution with 4 days of right arm and leg weakness, the salient past history of the patient was nephrotic syndrome, membranous nephropathy diagnosed 6 months prior, for which she was prescribed glucocorticoids and cyclophosphamide. DIAGNOSIS: Listeria monocytogenes was cultured in the blood of the patient. Comprehensive medical history and imaging features, she was diagnosed as listeria brain abscess. INTERVENTIONS: The patient underwent ampicillin combined with meropenem but not surgery. OUTCOMES: The patient recovered without complications. At a 3-month follow-up visit, the condition was better than that before treatment. LESSONS: Listeria brain abscess is an unusual form of listeriosis, its clinical manifestations lack specificity. Early accurate diagnosis and standardized treatment can effectively promote the recovery of neurological function as well as reduce the morbidity and mortality and improve the prognosis.

Dosing Optimization of Ampicillin-Sulbactam Based on Cystatin C in Elderly Patients with Pneumonia.

Ampicillin-sulbactam is a first-line therapy for pneumonia and is mainly excreted by the kidney. It is important to optimize the dose and dosing interval of ampicillin-sulbactam because in patients with decreased renal function and low skeletal muscle mass, such as the elderly, excess drug may burden renal function. In this study, we evaluated indices of renal function and optimized the dose and dosing interval of ampicillin-sulbactam based on pharmacokinetics (PK) and pharmacodynamics theory in elderly patients. The serum concentrations of ampicillin and sulbactam were measured by HPLC, and PK parameters were calculated. Correlations between the clearance of ampicillin or sulbactam and renal function were evaluated, and dosing optimization was calculated based on PK parameters. The PK parameters of ampicillin were CL = 6.5 ± 4.0 L/h, Vd = 19.3 ± 0.2 L, Ke = 0.4 ± 0.2, and t1/2 = 2.7 ± 1.6 h. The most correlated renal function index was estimated glomerular filtration rate (eGFRcys-c) calculated by serum cystatin-c (r = 0.7374, correlation formula; CL of ampicillin = 0.1937 × eGFRcys-c-0.6726). Based on this formula, we calculated the clearance of ampicillin and developed dosing regimens for the elderly. Serum cystatin-c concentration is an ideal index to optimize ampicillin-sulbactam antimicrobial therapy in elderly patients with pneumonia.

In vitro evaluation of 99m Tc-sultamicillin for infection imaging.

Early detection of the site of infection non-invasively with radiolabeled molecules is important for the success of treatment. Technetium-99m labeled antibiotics have the potential to discriminate between bacterial infection and sterile inflammation. Sultamicillin is the tosylate salt of the double ester of sulbactam plus ampicillin. In this study, sultamicillin was labeled with 99m Tc according to the stannous chloride method. Quality control studies of radiolabeled sultamicillin were performed by radiochromatographic methods. In vitro binding assays were performed in live and heat-killed gram-positive Staphylococcus aureus and gram-negative Escherichia coli strains. The radiolabeling yield of 99m Tc-sultamicillin was determined as 97.8% ± 3.1% (n = 5). The maximum bacterial uptake of 99m Tc-sultamicillin was 80.7% ± 11.00% at 4 h for living S. aureus and 93.2% ± 4.40% at 2 h for E. coli. Bacterial uptake study results show that sultamicillin has the potential to be a nuclear imaging agent, especially in infections caused by gram-negative E. coli and gram-positive S. aureus.

Effects of dosing frequency on the clinical efficacy of ampicillin/sulbactam in Japanese elderly patients with pneumonia: A single-center retrospective observational study.

This study sought to investigate whether dosing frequency (the number of doses per day) affects the antimicrobial efficacy and safety of ampicillin/sulbactam (ABPC/SBT) in Japanese elderly pneumonia patients treated with ABPC/SBT at 6 g/day. This was a retrospective observational study that included hospitalized elderly patients (aged ≥75 years, 10 ml/min ≤CLcr <50 ml/min) who received 3 g every 12 h (BID; n = 61) or 1.5 g every 6 h (QID; n = 45) for the treatment of pneumonia. The primary endpoint was clinical response, assessed by measuring body temperature, white blood cell count, and C-reactive protein levels. Pharmacokinetic and pharmacodynamic simulations were conducted in silico to rationalize the clinical findings. The clinical response rates (extremely effective and effective) in the BID and QID groups were 36.1% and 55.6%, respectively (p = .0459). QID tended to be more effective in patients with gram-negative rods detected (p = .0563). According to the simulated minimum plasma ABPC concentrations at steady state for BID and QID were 2.5 and 7.3 µg/ml, respectively (p < .0001). Based on the simulated time above minimum inhibitory concentration (MIC), pharmacological (not clinical) efficacy was predicted to be higher with QID. Both groups had similar safety profiles. The main adverse event in both groups was liver damage. The present retrospective survey demonstrated that ABPC/SBT treatment for elderly patients with pneumonia and renal dysfunction was more effective with QID than with BID. Therefore, the QID regimen is worthy of consideration to improve the clinical outcomes of ABPC/SBT therapy in the present patient population.

Maternal antibiotic administration during a critical developmental window has enduring neurobehavioural effects in offspring mice.

Rates of perinatal maternal antibiotic use have increased in recent years linked to prophylactic antibiotic use following Caesarean section delivery. This antibiotic use is necessary and beneficial in the short-term; however, long-term consequences on brain and behaviour have not been studied in detail. Here, we endeavoured to determine whether maternal administration of antibiotics during a critical window of development in early life has lasting effects on brain and behaviour in offspring mice. To this end we studied two different antibiotic preparations (single administration of Phenoxymethylpenicillin at 31 mg/kg/day; and a cocktail consisting of, ampicillin 1 mg/mL; vancomycin 0.5 mg/mL; metronidazole 1 mg/mL; ciprofloxacin 0.2 mg/mL and imipenem 0.25 mg/mL). It was observed that early life exposure to maternal antibiotics led to persistent alterations in anxiety, sociability and cognitive behaviours. These effects in general were greater in animals treated with the broad-spectrum antibiotic cocktail compared to a single antibiotic with the exception of deficits in social recognition which were more robustly observed in Penicillin V exposed animals. Given the prevalence of maternal antibiotic use, our findings have potentially significant translational relevance, particularly considering the implications on infant health during this critical period and into later life.

Ampicillin Pharmacokinetics During First Week of Life in Preterm and Term Neonates.

BACKGROUND AND AIMS: Ampicillin is 1 of the most commonly used antibiotics for treatment of early onset sepsis, but its pharmacokinetics (PK) is poorly characterized. We aimed to define the dose of ampicillin for late preterm and term neonates by evaluating its PK in serum, cerebrospinal (CSF), and epithelial lining fluid. METHODS: A prospective study included neonates receiving ampicillin for suspected or proven early onset sepsis and pneumonia. PK samples were collected at steady state, at predose and 5 minutes, 1 hour, 3 hours, 8 hours, and 12 hours after ampicillin 3-minute infusion. Ampicillin concentrations were measured by ultra-high-performance liquid chromatography. Noncompartmental anaysis (NCA) and population pharmacokinetic (pop-PK) modeling were performed and probability of therapeutic target attainment was simulated. RESULTS: In 14 neonates (GA of 32-42 wks; mean BW 2873 g), PK parameters (mean ± SD) in NCA were the following: half-life 7.21 ± 7.97 hours; volume of distribution (Vd) 1.07 ± 0.51 L; clearance (CL) 0.20 ± 0.13 L/h; 24-hour area under the concentration-time curve 348.92 ± 114.86 mg*h/L. In pop-PK analysis, a 2-compartmental model described the data most adequately with the final parameter estimates of CL 15.15 (CV 40.47%) L/h/70kg; central Vd 24.87 (CV 37.91%) L/70kg; intercompartmental CL 0.39 (CV 868.56) L/h and peripheral Vd 1.039 (CV 69.32%) L. Peutic target attainment simulations demonstrated that a dosage of 50 mg/kg q 12 hours attained 100% fT > MIC 0.25 mg/L, group B streptococcal breakpoint. CONCLUSIONS: We recommend ampicillin dosage 50 mg/kg q 12 hours for neonates with gestational age ≥32 weeks during the first week of life.

Antibiotics for Prophylaxis in the Setting of Preterm Prelabor Rupture of Membranes.

"For many years, providers have been using antibiotics to prevent infection in women who present with preterm prelabor rupture of membranes (PPROM). Given the polymicrobial nature of intra-amniotic infection, the recommended regimen includes a 7-day course of ampicillin and erythromycin, although many substitute of azithromycin. This regimen is used from viability to 34 weeks, independent of the number of fetuses present. Meta-analyses have shown that antibiotics for this indication are associated with lower rates of maternal and fetal infection, as well as longer pregnancy latency. Thus, latency antibiotics are recommended for all women with PPROM through 34 weeks of gestation."

Intraperitoneal ampicillin treatment for peritoneal dialysis- related peritonitis with Listeria monocytogenes - a case report.

BACKGROUND: Peritoneal dialysis (PD)-related peritonitis is a rare but serious complication and is associated with increased morbidity and mortality rates. It is most commonly caused by Staphylococcus aureus or Staphylococcus epidermidis, but infection with Listeria monocytogenes may also occur. Recommendations for antibiotic treatment of a Listeria infection are currently based on a small number of case reports and suggest the administration of ampicillin. But unlike vancomycin or gentamicin, for ampicillin the route of application, the dosage, and the duration of treatment have not yet been established. We report a case in which PD-associated peritonitis due to Listeria infection was treated with ampicillin administered intravenously and intraperitoneally, separately and in combination. CASE PRESENTATION: A 72-year-old man with chronic kidney disease stage 5 dialysis (CKDG5D) secondary to hypertension and diabetes was hospitalised in April 2020 because of PD-related peritonitis caused by a Listeria infection. In accordance with the results of resistance tests, the patient was treated with intravenous ampicillin at a dosage of 6 g twice daily. After initial treatment the leukocyte count in the PD effluent had decreased substantially, but it was permanently reduced only with the addition of intraperitoneal ampicillin (4 g daily). Efficient serum concentrations of ampicillin were determined for both routes of administration, intravenous and intraperitoneal. CONCLUSION: This is the first case report demonstrating that PD-related peritonitis due to Listeria monocytogenes infection can be treated with intraperitoneal ampicillin and monitored by the determination of peripheral serum concentrations of ampicillin.

Ampicillin/Sulbactam Treatment Modulates NMDA Receptor NR2B Subunit and Attenuates Neuroinflammation and Alcohol Intake in Male High Alcohol Drinking Rats.

Exposure to ethanol commonly manifests neuroinflammation. Beta (ß)-lactam antibiotics attenuate ethanol drinking through upregulation of astroglial glutamate transporters, especially glutamate transporter-1 (GLT-1), in the mesocorticolimbic brain regions, including the nucleus accumbens (Acb). However, the effect of ß-lactam antibiotics on neuroinflammation in animals chronically exposed to ethanol has not been fully investigated. In this study, we evaluated the effects of ampicillin/sulbactam (AMP/SUL, 100 and 200 mg/kg, i.p.) on ethanol consumption in high alcohol drinking (HAD1) rats. Additionally, we investigated the effects of AMP/SUL on GLT-1 and N-methyl-d-aspartate (NMDA) receptor subtypes (NR2A and NR2B) in the Acb core (AcbCo) and Acb shell (AcbSh). We found that AMP/SUL at both doses attenuated ethanol consumption and restored ethanol-decreased GLT-1 and NR2B expression in the AcbSh and AcbCo, respectively. Moreover, AMP/SUL (200 mg/kg, i.p.) reduced ethanol-increased high mobility group box 1 (HMGB1) and receptor for advanced glycation end-products (RAGE) expression in the AcbSh. Moreover, both doses of AMP/SUL attenuated ethanol-elevated tumor necrosis factor-alpha (TNF-α) in the AcbSh. Our results suggest that AMP/SUL attenuates ethanol drinking and modulates NMDA receptor NR2B subunits and HMGB1-associated pathways.

Mechanistic Insights Into the Differential Efficacy of Daptomycin Plus ß-Lactam Combinations Against Daptomycin-Resistant Enterococcus faecium.

BACKGROUND: The combination of daptomycin (DAP) plus ampicillin (AMP), ertapenem (ERT), or ceftaroline has been demonstrated to be efficacious against a DAP-tolerant Enterococcus faecium strain (HOU503). However, the mechanism for the efficacy of these combinations against DAP-resistant (DAP-R) E. faecium strains is unknown. METHODS: We investigated the efficacy of DAP in combination with AMP, ERT, ceftaroline, ceftriaxone, or amoxicillin against DAP-R E. faecium R497 using established in vitro and in vivo models. We evaluated pbp expression, levels of penicillin-binding protein (PBP) 5 (PBP5) and ß-lactam binding affinity in HOU503 versus R497. RESULTS: DAP plus AMP was the only efficacious regimen against DAP-R R497 and prevented emergence of resistance. DAP at 8, 6, and 4 mg/kg in combination with AMP was efficacious but showed delayed killing compared with 10 mg/kg. PBP5 of HOU503 exhibited amino acid substitutions in the penicillin-binding domain relative to R497. No difference in pbp mRNA or PBP5 levels was detected between HOU503 and R497. labeling of PBPs with Bocillin FL, a fluorescent penicillin derivative, showed increased ß-lactam binding affinity of PBP5 of HOU503 compared with that of R497. CONCLUSIONS: Only DAP (10 mg/kg) plus AMP or amoxicillin was efficacious against a DAP-R E. faecium strain, and pbp5 alleles may be important contributors to efficacy of DAP plus ß-lactam therapy.

Contemporaneous management of ampicillin infusions in the outpatient setting through the use of therapeutic drug monitoring.

The use of ampicillin in the outpatient setting has traditionally been avoided because of the short half-life and instability in solution of this drug. However, recent in vitro data and two case series support the safe and effective administration of ampicillin by continuous infusion in the community. Therapeutic drug monitoring (TDM) of beta-lactam antibiotics can be used to optimise antibiotic exposure and ensure adequate clinical responses. A case series is presented of patients receiving ampicillin via prolonged infusion in the outpatient setting, with TDM to ensure adequate plasma antibiotic levels were achieved. Three patients who received ampicillin by continuous infusion under the Outpatient Parenteral Antimicrobial Therapy (OPAT) program are described, including details of antibiotic dose and steady-state plasma drug concentration as measured by high-performance liquid chromatography. All three patients had an infection with ampicillin-susceptible Enterococcus faecalis; one patient had post-partum endometritis, one had urosepsis and one had a complex polymicrobial bone and joint infection. Adequate plasma drug levels were achieved in all patients. Management of the antibiotic temperature and infusion times, and appropriate timing of drug levels in the community were required. Two patients achieved clinical cure, while the third required further surgical debridement and antibiotic therapy. TDM in this setting enabled the contemporaneous management and dose alteration of ampicillin. Ampicillin may be a safe and effective drug when administered by continuous infusion with appropriate TDM in the community setting.

Intestinal Bacteria Maintain Adult Enteric Nervous System and Nitrergic Neurons via Toll-like Receptor 2-induced Neurogenesis in Mice.

BACKGROUND & AIMS: The enteric nervous system (ENS) exists in close proximity to luminal bacteria. Intestinal microbes regulate ENS development, but little is known about their effects on adult enteric neurons. We investigated whether intestinal bacteria or their products affect the adult ENS via toll-like receptors (TLRs) in mice. METHODS: We performed studies with conventional C57/BL6, germ-free C57/BL6, Nestin-creERT2:tdTomato, Nestin-GFP, and ChAT-cre:tdTomato. Mice were given drinking water with ampicillin or without (controls). Germ-free mice were given drinking water with TLR2 agonist or without (controls). Some mice were given a blocking antibody against TLR2 or a TLR4 inhibitor. We performed whole gut transit, bead latency, and geometric center studies. Feces were collected and analyzed by 16S ribosomal RNA gene sequencing. Longitudinal muscle myenteric plexus (LMMP) tissues were collected, analyzed by immunohistochemistry, and levels of nitric oxide were measured. Cells were isolated from colonic LMMP of Nestin-creERT2:tdTomato mice and incubated with agonists of TLR2 (receptor for gram-positive bacteria), TLR4 (receptor for gram-negative bacteria), or distilled water (control) and analyzed by flow cytometry. RESULTS: Stool from mice given ampicillin had altered composition of gut microbiota with reduced abundance of gram-positive bacteria and increased abundance of gram-negative bacteria, compared with mice given only water. Mice given ampicillin had reduced colon motility compared with mice given only water, and their colonic LMMP had reduced numbers of nitrergic neurons, reduced neuronal nitric oxide synthase production, and reduced colonic neurogenesis. Numbers of colonic myenteric neurons increased after mice were switched from ampicillin to plain water, with increased markers of neurogenesis. Nestin-positive enteric neural precursor cells expressed TLR2 and TLR4. In cells isolated from the colonic LMMP, incubation with the TLR2 agonist increased the percentage of neurons originating from enteric neural precursor cells to approximately 10%, compared with approximately 0.01% in cells incubated with the TLR4 agonist or distilled water. Mice given an antibody against TLR2 had prolonged whole gut transit times; their colonic LMMP had reduced total neurons and a smaller proportion of nitrergic neurons per ganglion, and reduced markers of neurogenesis compared with mice given saline. Colonic LMMP of mice given the TLR4 inhibitor did not have reduced markers of neurogenesis. Colonic LMMP of germ-free mice given TLR2 agonist had increased neuronal numbers compared with control germ-free mice. CONCLUSIONS: In the adult mouse colon, TLR2 promotes colonic neurogenesis, regulated by intestinal bacteria. Our findings indicate that colonic microbiota help maintain the adult ENS via a specific signaling pathway. Pharmacologic and probiotic approaches directed towards specific TLR2 signaling processes might be developed for treatment of colonic motility disorders related to use of antibiotics or other factors.

[Inadvertent epidural ampicillin administration during labor: case report]. / Administração peridural inadvertida de ampicilina durante trabalho de parto: relato de caso.

BACKGROUND: Inadvertent epidural drug administration is associated with morbidity and mortality. Several drugs have been administered accidentally through the epidural catheter and most of our knowledge is based on case reports. CASE REPORT: A 33 year-old woman presented for delivery. Placement of epidural catheter was requested for labor analgesia and priming dose was administered. Five minutes later, ampicillin 1g was given through the catheter inadvertently without hemodynamic or neurological changes. Ropivacaine administration was repeated, always with symptomatic relief until delivery. At hospital discharge, she remained without neurological or hemodynamic alterations. CONCLUSIONS: The majority of errors are due to syringe and drug exchanges, and inadvertent route administration. Erroneous administration into the epidural space can have immediate and late effects and there is no definitive and effective treatment. There are several preventive measures to reduce the potential complications; some opt for watchful waiting, others opt for administering other drugs as a dilution attempted.