Tratamiento de la sífilis temprana en pacientes infectados con VIH: una dosis de penicilina benzatínica es suficiente / The outcome of treatment of early syphilis in HIV-infected patients: a single dose of benzathine penicillin seems sufficient

Comparar la respuesta clínica y serológica de pacientes infectados con VIH y sífilis temprana según hubieran recibido 1 ó más dosis de penicilina benzatínica, y evaluar factores asociados a fallo del tratamiento. Métodos: estudio retrospectivo, observacional, descriptivo en pacientes infectados con VIH tratados con penicilina benzatínica por sífilis temprana entre 1999-2009. Se consideró régimen corto de enicilina benzatínica 2.400.000 unidades cuando se administró 1 dosis, y régimen largo cuando se administraron más de 1 dosis. Se definió respuesta serológica adecuada al descenso de 4 títulos de la VDRL tras 6-12 meses del tratamiento. Se compraron las frcuencias de las respuestas serológicas mediante tablas de contingencia de 2x2; se determinó la significación estadística mediante la prueba de Chi2 corregida por Yates; las variables continuas se analizaron mediante Mann-Whitney; las proporciones se compararon mediante la prueba de las proporciones para dos muestras (Statistix 7.0). Las diferencias fueron consideradas significativas cuando p fue< 0,05. Resultados: evaluamos 237 eventos de sífilis temprana. Todos los pacientes con sífilis primaria y secundaria resolvieron los signos o síntomas de la enfermedad. Hubo respuesta serológica adecuada en 92,9 % y 90,99 % de quienes recibieron régimen corto versus largo respectivamente (p=0,59). No observamos diferencias significativas en los porcentajes de pacientes con respuesta serológica adecuada entre quienes recibieron el régimen corto o largo en ninguno de los subgrupos conformados: estratos de CD4, pacientes con o sin sida, con o sin TARGA, presentación clínica de la sífilis temprana y título de VDRL. Conclusiones: en nuestra experiencia, para tratar la sífilis temprana en pacientes con VIH, una dosis de penicilina benzatínica fue suficiente. No se halló ningún factor asociado a fallo serológico...

To compare the serological and clinical response to treatment of early syphilis in HIV-infected patients who received a single-dose versus more than 1 dose of benzathine penicillin 2.4 millon U associated with treatment failure. Methods: retrospective, observational, descriptive study (1999-2009). Adequate serological response was defined as at least a four-fold decrease in VDRL titers at 6-12 months of treatment. We compared the rate of response with contingency tables; the statistic significance was determined by Yate's corrected x 2 test; for continuous variables analysis Mann-Whitney was applied; to compare proportions, the proportion test was applied (Statistix 7.0). Differences were considered significant if p< 0,05. Results: 237 HIV-infected patients with early syphilis were evaluated. Every patient with primary or secondary syphilis resolved the signs or sympthoms of the disease. We found an adequate serological response in 92.9 % versus 90.99% of whom received a single-dose versus >1 doses of benzathine penicillin 2.4 million U, respectively (p=0.59). The difference between groups was not statistically significant regardless of their CD4 cell count, antiretroviral tretment, AIDS status or VDRL titer. Conclusions: in our experience, a single dose of benzathine penicillin 2.4 million U for the treatment of early syphilis in HIV-infected patients was sufficient to achieve an adequate serological response. None factor was found to be associated wth serological failure...

Penicillin concentrations in sera and tonsils after intramuscular administration of benzathine penicillin G to children.

BACKGROUND: The optimal regimen of benzathine penicillin G for secondary prevention of rheumatic fever is controversial. Data from serum pharmacokinetic studies do not fully agree on the period of protection after drug administration. Data from concentration of penicillin in tonsils may provide additional information. METHODS: To evaluate penicillin concentrations in palatine tonsils and in sera 1, 10, 14 and 21 days after intramuscular injection of benzathine penicillin G 40,000 IU/kg, 58 children between 4 and 12 years of age with chronic tonsillitis and indication for tonsillectomy were given the study drug 1, 10, 14 or 21 days before surgery. Blood and tonsil samples were obtained during surgery, and penicillin concentrations were determined microbiologically by the agar well diffusion technique. RESULTS: Mean serum penicillin concentrations 1, 10, 14 and 21 days after drug administration were, respectively, 0.080, 0.031, 0.023 and 0.014 microg/ml. Mean penicillin concentrations in tonsils at 1, 10, 14 and 21 days were 0.023, 0.010, 0.007 and 0.002 microg/g, respectively. Detectable penicillin concentration in tonsils (method sensitivity, 0.006 microg/g) was obtained in all patients on Day 1 and in 91% and 83.3% of patients on Days 10 and 14, respectively. By Day 21 this proportion was reduced to 30%. CONCLUSIONS: The results of this study suggest that penicillin values may be inadequate for prevention of rheumatic fever by Week 3 of administration in a majority of children.

Colloidal carriers for benzathine penicillin G: nanoemulsions and nanocapsules.

The main purpose of this work is to formulate benzathine penicillin G nanoemulsion and nanocapsules, to evaluate their physicochemical and stabilising characteristics, and to determine their antimicrobial activity and penicillin in vitro release kinetics. Nanoemulsions were produced by the spontaneous emulsification approach and nanocapsules of poly (D,L-lactic acid-co-glycolic acid) polymer (PLGA) were prepared by the method of interfacial deposition of a pre-formed polymer. A 207+/-8 nm mean diameter nanoemulsion formulation maintained stability for more than 5 months at 4 degrees C. Stable nanocapsules with 224+/-58 nm mean diameter were obtained, which remained stabilised over 120 days at 4 degrees C. The penicillin encapsulation ratio in the nanocapsules was 85%. The in vitro release profiles indicated that penicillin released from the nanoemulsion was similar to the one observed from nanocapsules. However it can be clearly deduced from the in vitro kinetic analysis that the antibiotic cannot be protected in colloidal delivery systems. Nevertheless, stable formulations obtained in this investigation supply a potential dosage form to encapsulate more easily soluble drugs.

La penicilina benzatina: previene el tétanos? / The benzatine penicillin: does it prevent tetanus?

El tétano es un problema de salud pública a nivel mundial, especialmente en los países en desarrollo. Chile no escapa a esta realidad, aunque la incidencia es mucho menor. La alta letalidad de esta enfermedad obliga a realizar un manejo adecuado de todos aquellos pacientes con heridas sospechosas, el que incluye aseo y debridación local junto al uso de la antitoxina tetánica. No existen evidencias de que la antibioterapia influya en su prevención

Pharmacokinetics of benzathine penicillin G: serum levels during the 28 days after intramuscular injection of 1,200,000 units.

Because of published data suggesting the inadequacy of once-every-4-weeks intramuscular injections of benzathine penicillin G for secondary rheumatic fever prevention, serum penicillin levels were determined at 1, 3, 10, 21, and 28 days after administration of 1,200,000 units of this repository penicillin. A total of 193 samples were studied. Mean serum penicillin levels remained greater than or equal to 0.02 micrograms/ml for 21 days, but by 28 days only 44% of the serum samples had detectable levels of penicillin and only 36% had levels greater than or equal to 0.02 micrograms/ml. Patients weighing more than 45 kg had significantly lower serum penicillin levels than did those who weighed less. There were similar correlations with body surface area and with age. These data indicate that a significant percentage of patients receiving benzathine penicillin G prophylaxis for prevention of recurrent attacks of rheumatic fever are not protected during the fourth week. More frequent administration of benzathine penicillin G should be considered in instances of high risk of recurrence of rheumatic fever.