Chitosan and cloxacillin combination improve antibiotic efficacy against different lifestyle of coagulase-negative Staphylococcus isolates from chronic bovine mastitis.

Bovine mastitis affects the health of dairy cows and the profitability of herds worldwide. Coagulase-negative staphylococci (CNS) are the most frequently isolated pathogens in bovine intramammary infection. Based on the wide range of antimicrobial, mucoadhesive and immunostimulant properties demonstrated by chitosan, we have evaluated therapy efficiency of chitosan incorporation to cloxacillin antibiotic as well as its effect against different bacterial lifestyles of seven CNS isolates from chronic intramammary infections. The therapeutic effects of combinations were evaluated on planktonic cultures, bacterial biofilms and intracellular growth in mammary epithelial cells. We found that biofilms and intracellular growth forms offered a strong protection against antibiotic therapy. On the other hand, we found that chitosan addition to cloxacillin efficiently reduced the antibiotic concentration necessary for bacterial killing in different lifestyle. Remarkably, the combined treatment was not only able to inhibit bacterial biofilm establishment and increase preformed biofilm eradication, but it also reduced intracellular bacterial viability while it increased IL-6 secretion by infected epithelial cells. These findings provide a new approach to prophylactic drying therapy that could help to improve conventional antimicrobial treatment against different forms of bacterial growth in an efficient, safer and greener manner reducing multiresistant bacteria generation and spread.

Evaluation of the efficacy of intramuscular versus intramammary treatment of subclinical Streptococcus agalactiae mastitis in dairy cows in Colombia.

A randomized controlled trial was performed in 17 Colombian dairy herds to determine the cure risk among cows subclinically infected with Streptococcus agalactiae exposed to 2 antibiotic therapies. Composite milk samples were collected before milking at the onset of the trial (pretreatment) and 2 subsequent times over a period of approximately 63 d. The intramammary application (IMM) of ampicillin-cloxacillin was compared with the intramuscular application (IM) of penethamate hydriodide, and cure risks after an initial and retreatment application were assessed. Cure risk after the initial treatment was higher (82.4%) for the IMM treatment than for IM therapy (65.8%). However, no difference was observed in the cure risk of refractory cases after retreatment (IMM=52.6% vs. IM=51.2%). The cumulative cure risk (both initial and retreatment) was 90.4 and 82.9% for the IMM and IM products, respectively. A 2-level random effects logistic model that controlled for pretreatment cow-level somatic cell count, indicated that IM treatment (odds ratio=0.37) had a lower cure risk than IMM and a tendency for a lower cure risk with increasing baseline somatic cell count. Our findings suggest that both products and administration routes can reduce the prevalence of S. agalactiae in affected herds, but the IMM product had a better efficacy in curing the infection. In addition to the treatment protocol, the cow somatic cell count should be considered when making management decisions for cows infected with S. agalactiae.

Histomorphometric changes in the testes and epididymis of wistar strain albino rats following fourteen days oral administration of therapeutic doses of some antibiotics / Cambios histomorfométricos en los testículos y el epidídimo de ratas cepa wistar albinas después de catorce días de administración oral de dosis terapéuticas de algunos antiobióticos

Studies on testes and epididymis tissue of rats treated orally for fourteen days with therapeutic doses of cloxacillin (6mg/100g/day), ampicillin (4mg/100/day) and tetracycline (12mg/100g/day) separately showed a significant reduction in testicular and epididimis architecture. Microscopic studies of these male reproductive organs further revealed a significant alteration in the epididymis as revealed by a significant reduction (p<0.05) in epididymal ductular diameter (EDD), and epididymal epithelial height (EEH) in treated group of animals. A significant increase (p<0.05) was however recorded in epididymal luminal diameter (ELD) in all the animals after the two and three week's recovery period allowed. This gives another insight into the toxicity activities of these antibiotics on male reproductive organs, apart from reduction in serum testosterone level, decreased sperm motility, decreased spermatozoa count and decrease in RNA and DNA content of spermatogenic cells as earlier reported.

Estudios referentes a testículos y tejido epididimario en ratas tratadas por vía oral durante catorce días, con dosis terapéuticas de cloxacilina (6mg/100g/día), ampicilina (4mg/100/día) y tetraciclina (12mg/100g/día) por separado muestran una reducción significativa en el peso testicular y epidídimario. Los estudios microscópicos de los órganos reproductores masculinos revelan además una alteración significativa en el epidídimo como se observa en la reducción del diámetro (p<0,05) de los conductos del epidídimo (EDD), y la altura del epitelio epididimal (EEH) en el grupo de los animales tratados. Sin embargo, se registró un aumento significativo (p <0,05) en el diámetro luminal del epidídimo (ELD) en todos los animales después de dos y tres semanas del período de recuperación. Esto genera otro punto de vista en relación a la toxicidad de estos antibióticos en los órganos reproductivos masculinos, además de la reducción de la concentración sérica de testosterona, disminución de la motilidad del esperma, disminución del recuento de espermatozoides y disminución en el contenido de ARN y ADN en las células de espermatogénesis como se reportó anteriormente.

[Short duration of initial intravenous treatment in 70 pediatric patients with osteoarticular infections]. / Tratamiento intravenoso inicial abreviado en 70 pacientes pediátricos con infecciones osteo-articulares.

UNLABELLED: Osteoarticular infections (OAI) are infrequent in pediatrics and there is controversy on the need for prolonged use of intravenous antimicrobials. OBJECTIVE: To characterize and describe evolution and complications of a regimen of 7 days initial intravenous antibiotic treatment for OAI in children, completing 4-6 weeks of total treatment. PATIENTS AND METHODS: In a large pediatric hospital, 70 children younger than 15 years of age were diagnosed with OAI between March 2003 and December 2004. Children received 7 days of intravenous antibiotics followed by 3 to 5 weeks of oral treatment. RESULTS: Incidence of OAI in this hospital was 1.8:10000. Patients mean age was 6.4 +/-4.4 years and 60% presented with septic arthritis, 36% osteomyelitis and 4% osteoarthritis. In 80% of cases, the infection was located in the lower extremity. Positive cultures were obtained in 59% predominating Staphylococcus aureus (46.5%). Seven patients had prolonged pain or persistently high or increasing serum C reactive protein levels and were maintained on prolonged intravenous therapy. None of the 63 children with 7 day intravenous antimicrobials nor the 7 children with prolonged intravenous use developed a complication in the short-term follow up. CONCLUSIONS: Seven days of intravenous antibiotic for the initial phase of OAI treatment was effective in a majority of children and may be recommended.

Tratamiento intravenoso inicial abreviado en 70 pacientes pediátricos con infecciones osteo-articulares / Short duration of initial intravenous treatment in 70 pediatric patients with osteoarticular infections

Osteoarticular infections (OAI) are infrequent in pediatrics and there is controversy on the need for prolonged use of intravenous antimicrobials. Objective: To characterize and describe evolution and complications of a regimen of 7 days initial intravenous antibiotic treatment for OAI in children, completing 4-6 weeks of total treatment. Patients and methods: In a large pediatric hospital, 70 children younger than 15 years of age were diagnosed with OAI between March 2003 and December 2004. Children received 7 days of intravenous antibiotics followed by 3 to 5 weeks of oral treatment. Results: Incidence of OAI in this hospital was 1.8:10000. Patients mean age was 6.4 ±4.4 years and 60 percent presented with septic arthritis, 36 percent osteomyelitis and 4 percent osteoarthritis. In 80 percent of cases, the infection was located in the lower extremity. Positive cultures were obtained in 59 percent predominating Staphylococcus aureus (46.5 percent). Seven patients had prolonged pain or persistantly high or increasing serum C reactive protein levels and were maintained on prolonged intravenous therapy. None of the 63 children with 7 day intravenous antimicrobials nor the 7 children with prolonged intravenous use developed a complication in the short-term follow up. Conclusions: Seven days of intravenous antibiotic for the initial phase of OAI treatment was effective in a majority of children and may be recommended.

Las infecciones osteoarticulares (IOA) son poco frecuentes en pediatría. Existe controversia acerca de la óptima duración y la vía de administración de la terapia antimicrobiana. Objetivo: Caracterizar y describir la evolución y complicaciones en niños con IOA que recibieron 7 días iniciales de terapia endovenosa, completando 4 a 6 semanas de terapia total. Pacientes y Métodos: Estudio descriptivo, que incluyó a 70 niños con diagnóstico de IOA, entre marzo de 2003 y diciembre de 2004 en un hospital pediátrico, quienes recibieron tratamiento endovenoso abreviado a 7 días, seguido de terapia oral por 3 a 5 semanas. Resultados: La incidencia de IOA fue de 1,8: 10.000 niños bajo 15 años de edad. El promedio de edad fue 6,4 ± 4,4 años. Sesenta por ciento presentaba artritis séptica, 36 por ciento osteomielitis y 4 por ciento osteoartritis. En 80 por ciento la infección se localizó en extremidades inferiores. Los cultivos fueron positivos en 59 por ciento. En 46,5 por ciento se aisló Staphylococcus aureus. Siete niños evolucionaron con dolor persistente o elevación significativa de PCR y requirieron prolongar la terapia endovenosa y/o total, sin presentar complicaciones a corto plazo. Conclusiones: Siete días de terapia antimicrobiana intravenosa parece ser efectivo y recomendable para el tratamiento, en su fase inicial, de las infecciones osteo-articulares.

Isquemia aguda de la mano secundaria a la admmnistración intraarterial de cloxacilina / Hand acute ischemia secondary to the intraarterial administration of cloxaciline

La isquemia aguda de la mano, luego de la inyección intraarterial de medicamentoses un problema frecuente, de difícil manejo, y que requiere tratamiento médico urgente. Este reporte describe un caso de inyección inadvertido de cloxacilina en arteria humeral, con isquemia grave de mano, que llegó a la amputación digital. Se discute patogénesis y opciones de tratamiento

Tiroiditis subaguda y supuración tiroidea concomitante en 1 caso / Subacute thyroiditis and concomitant thyroidal abscedation in 1 case

We report a 41 years old man adnitted with tender goiter, fever, thyrotoxic manifestations and atrial fibrillation. Laboratory confirmed the diagnosis of subacute thyroiditis and treatment with aspirin and propanolol was started, obtaining a rapid relief of symptoms and normalization of heart rate. On the 10th day after admission, severe dysfagia, dysphonia, irritative cough and further enlargement of the neck mass developed. Fine needle aspiration of the mass and thyroid ultrasound lead to the diagnosis of a thyroidal abscess, which was surgically excised, draining 250 ml of purulent material. Cultures were positive for Staphylococcus aureus. Patient was treated during 21 with cloxacilyn and discharged with normal thyroid function. Long term follow-up has been uneventful

Prevención de las infecciones postoperatorias en neurocirugía / Prevention of postoperative infections in neurosurgery

Analizamos las infecciones postoperatorias en 866 pacientes. El lavado de campo operatorio se efectuó con clorhexidina y se inyectó cloxacilina profiláctica. Hubo 1 infección de la herida operatoria (0,1 por ciento). El tiempo de seguimiento fluctuó entre 9 meses y 4 años. El método mostró ser eficaz, sin casos de sobreinfección, alergia ni toxicidad sistémica, pero al no haber un control, no permite concluir que se debe usar ATB profilácticos en todos los pacientes neuroquirúrgicos. La situación epidemiológica es diferente en cada hospital, siendo el diagnóstico local fundamental en la elaboración de programas de prevención. Es necesario definir las cirugías con mayor riesgo de infecciones postoperatorias y los gérmenes más probables y según esto establecer el esquema ATB profiláctico

Acute fevers of unknown origin in young children in the tropics.

Bacteremia was documented in 14 of 156 previously healthy children with temperatures of at least 40.0 degrees C but without focal signs, seen in an emergency department; 116 children had malaria, and no infections were identified in 26. Concurrent malaria infection was frequent in children with bacteremia. The highly febrile child without focal signs in the tropics requires evaluation for bacteremia even when a diagnosis of malaria has been confirmed.

Estudio clínico comparativo de mupirocine tópico y cloxacilina oral en el tratamiento de infecciones cutáneas / Comparative clinique study of topical mupirocine and oral cloxacillin in the treatment of skin infections

Comparamos en un estudio randomizado la efectividad en el tratamiento de enfermedades cutáneas superficiales con mupirocine tópico y cloxacilina oral. Los resultados demostraron un a mejor respuesta con mupirocine, con 85,7 por ciento de eliminación bacteriana a la semana post-tratamiento versus un 54,5 por ciento con cloxacilina. No se reportaron efectos sistémicos colaterales con mupirocine excepto prurito y sensación de ardor

Cloxacillin absorption and disposition in cystic fibrosis.

Because of reports of lowered antibiotic serum concentrations in patients with cystic fibrosis (CF), a bioavailability and pharmacokinetic study of cloxacillin was conducted in 12 control and 16 patients with CF after intravenously and orally administered doses of cloxacillin 25 mg/kg. The patients had mild to moderate CF and were in stable condition. Significantly lower serum concentrations in CF were a result of a 78% increase in total body clearance (P less than 0.005) and a 38% increase in the apparent volume of distribution (P less than 0.025). The bioavailability in CF (0.50) was not significantly different than in controls (0.38), but more variability was seen in the group with CF. After the intravenously given dose the fraction of cloxacillin excreted in the urine unchanged was similar in controls (0.644) and patients with CF (0.547). Compared with that in the control subjects, the mean renal clearance in patients with CF was 30% greater (P less than 0.10) and the nonrenal clearance was 144% greater (P less than 0.07). Enhanced nonrenal clearance explains most of the demonstrated difference between serum concentrations in controls and patients with CF after identical weight-adjusted doses. The data suggest enhanced cloxacillin biotransformation in CF.

Antibiotic prophylaxis in cystic fibrosis: inhaled cephaloridine as an adjunct to oral cloxacillin.

The effect of prophylactic antibiotics on bacterial colonization of the respiratory tract and on general progression of cystic fibrosis was studied in a two-year prospective study of 47 mildly to moderately affected patients. One group of patients received inhaled cephaloridine and the other received no inhaled antibiotic; both groups received cloxacillin orally. Carriage of Haemophilus influenzae was greater in the group not receiving inhaled antibiotic (55% vs 20%). Rates of carriage of Staphylococcus aureus (23%). Pseudomonas aeruginosa (greater than 90%). Pseudomonas cepacia (45%), and other organisms were similar in both groups. There were no significant differences between the two groups in incidence of respiratory tract infections or hospital admissions, clinical scores, radiologic scores, or rate of change of pulmonary function. Although continuous antistaphylococcal antibiotic prophylaxis may be successful in suppressing colonization with S. aureus, it may also contribute to the high rates of carriage of Ps. aeruginosa and Ps. cepacia observed in patients with cystic fibrosis.