Adrenal cortex stimulation with hCG in spayed female dogs with Cushing's syndrome: Is the LH-dependent variant possible?

Background: The expression and overexpression of luteinizing hormone (LH) receptors in the canine adrenal gland cortex have been reported. Therefore, it was hypothesized that a LH-dependent form of Cushing's syndrome (CS) could exist in dogs. Aim: To assess whether the adrenal gland post-ovariectomy (OVx) exhibits a greater response to adrenocorticotrophin (ACTH) stimulation; to evaluate whether the adrenal gland responds to human chorionic gonadotropin (hCG) stimulation by increasing the release of cortisol; and to consider whether hCG stimulus testing would be useful as a diagnosis for possible cases of LH-dependent CS. Methods: Cortisol concentrations were measured from healthy female dogs (n=16) at baseline and following ACTH stimulation before and 2 months after gonadectomy (OVx). Cortisol concentrations were also measured for female dogs with CS (n = 14) following administration of hCG (5000 IU). A post-hCG cortisol concentration greater than 140 nmol/l was used to define dogs with LH-dependent Cushing's syndrome. Results: In normal female dogs, both pre- and post-stimulation cortisol concentrations increased following OVx (p = 0.002 and p = 0.0003, respectively). In female dogs with CS, cortisol concentrations increased following stimulation with hCG in 57% (8/14; p = 0.002). Age at the time of OVx was associated (p = 0.015) with the cortisol response to hCG [8 (5-9) years vs. 3.5 (2-6) years, p = 0.0013). Conclusion: Based on these results, an LH-dependent form of CS occurs in spayed female dogs, and that it is more likely to occur when female dogs are spayed later in life.

Diabetes mellitus remission in three cats with hypersomatotropism after cabergoline treatment.

CASE SUMMARY: Three diabetic cats presented with polyuria, polydipsia, polyphagia and poor glycemic control. Cat 1 displayed prognathia inferior and had a body condition score (BCS) of 4/5; cat 2 had a BCS of 5/5; and cat 3 had broad facial features. Serum insulin-like growth factor 1 concentrations were compatible with hypersomatotropism in cat 1 and cat 2 (>1500 ng/ml and 1200 ng/ml, respectively) and just below the cut-off of 1000 ng/ml (947 ng/ml) in cat 3; in this last cat diagnosis was further supported by the presence of pituitary enlargement on MRI. Oral cabergoline (10 µg/kg q48h) was initiated. Insulin requirements progressively reduced, as evidenced by daily blood glucose monitoring and weekly blood glucose curves. Diabetic remission occurred in all three cats between the second and third months of cabergoline treatment. At the time of writing, remission has persisted thus far (cat 1: 23 months; cat 2: 14 months; cat 3: 38 months). RELEVANCE AND NOVEL INFORMATION: To our knowledge, these are the first reported cases of diabetic remission in cats with hypersomatotropism after cabergoline treatment, despite previous reports of this being an ineffective treatment. Further work is indicated to determine why some cats do, and others do not, respond to this treatment.

Metformin reduces insulin resistance and the tendency toward hyperglycaemia and dyslipidaemia in dogs with hyperadrenocorticism.

Hypercortisolism induces a state of insulin resistance that can occur concurrently with fasting hyperglycaemia, dyslipidaemia and diabetes mellitus. Metformin reduces hepatic glucose production and insulin resistance of the skeletal muscle and adipose tissue. The aim of this study was to evaluate the effects of metformin on the control of metabolic disorders of dogs with hyperadrenocorticism (HAC). Twenty-three dogs with HAC were randomly divided into two groups, consisting of a control group and a metformin group (10 mg metformin/kg/12 h). Both groups received the same treatment for HAC. At baseline and 3 months, blood glucose, total cholesterol, triglycerides and insulin concentrations, in addition to urinary cortisol:creatinine ratio, Homeostatic Model Assessment (HOMA) for insulin sensitivity and ß-cell function were measured. Dogs treated with metformin showed significantly reduced glycaemia, cholesterolaemia and triglyceridaemia. They also presented reduced hyperinsulinism and insulin resistance, as well as improved pancreatic ß-cell function. The implementation of metformin as an adjuvant therapy is effective for the normalisation of metabolic disorders of dogs with HAC.

Decrease of nitric oxide and increase in diastolic blood pressure are two events that affect renal function in dogs with pituitary dependent hyperadrenocorticism.

Hyperadrenocorticism is a frequent disease in dogs. The excess of circulating cortisol affects different organs and metabolic pathways, producing severe adverse effects that endanger the animal's life. Among these effects, hypertension and renal damage can be mentioned. A group of 20 dogs with pituitary dependent hyperadrenocorticism (PDH) and 12 control dogs were used to study the following parameters: cortisol and nitric oxide (NO nit/nit) concentrations, diastolic and systolic blood pressure, renal artery resistance index by Doppler ultrasound, the rate of glomerular filtration by radio-renogram excretion and the presence of proteins in urine. Dogs with PDH showed a significantly lower NO nit/nit (P<0.0001) than the controls and this correlated with high values of diastolic and systolic pressure (r = -0.87; P<0.0001 and r = -0.81; P<0.0001 respectively). Most dogs (80%) are hypertensive mainly due to an increase in diastolic pressure, which correlated positively with the UPC (r = 0.8; P<0.001) and negatively with the glomerular rate of filtration (r = -0.58; P=0.007). Systolic pressure only increased in 60% of the cases and did not correlate with the mentioned variables. In PDH the decrease of NO affects blood pressure. The diastolic pressure would seem to have the greatest impact on the kidneys, therefore its evaluation and control are important to avoid and/or control renal damage.

Overexpression of 11ß-hydroxysteroid dehydrogenase 1 in visceral adipose tissue and underexpression of endothelial nitric oxide synthase in the adrenal cortex of dogs with hyperadrenocorticism.

11ß-Hydroxysteroid dehydrogenase 1 (11ß-HSD1) is an enzyme that activates cortisone into cortisol in tissues. Alterations in this enzyme are related to the development of metabolic syndrome, obesity and hyperadrenocorticism (HAC). Endothelial nitric oxide synthase (eNOS) produces nitric oxide and is related to the regulation of adrenal steroidogenesis. The aim of the study was to evaluate 11ß-HSD1 and eNOS expression in dogs with HAC. Visceral adipose tissue samples were taken to evaluate 11ß-HSD1 expression by immunohistochemistry and western blotting. In parallel, adrenal gland samples were collected to evaluate eNOS expression by immunohistochemistry. 11ß-HSD1 expression was significantly higher in the adipocytes of dogs with HAC than in those of the control dogs. eNOS expression in the adrenal cortex (zona fasciculata) was significantly lower in the dogs with HAC than in the control dogs. 11ß-HSD1 overexpression and eNOS underexpression could play a role in the maintenance of hypercortisolism in dogs with HAC.

Events temporarily associated with anti-influenza A (H1N1) vaccination in Mexico.

BACKGROUND AND AIMS: In Mexico from December 2009 to June 2010, 45,490,501 doses of the vaccine against the influenza virus were administered; 27,048,330 of those corresponded to influenza A (H1N1) and 18,442,171 to seasonal influenza. Therefore, the assessment of events temporarily associated with vaccination (ETAV) is mandatory. METHODS: The database corresponding to the ETAV associated with influenza (A [H1N1] and seasonal) immunization reported between December 2009 and June 2010 was analyzed. Patients who displayed at least one ETAV with one of the following schedules were included: A) influenza A (H1N1) vaccine, B) seasonal influenza vaccine, C) influenza A (H1N1) vaccine and seasonal influenza vaccine. RESULTS: A total of 597 ETAVs were reported. The 20- to 49-year-old age group was the most affected one (52.9%). The ETAV notification rate for influenza A (H1N1) vaccination was 1.41/100,000 applied doses vs. 0.74/100,000 applied doses corresponding to the seasonal influenza vaccination. Fifty seven events were considered serious (14 corresponded to Guillain-Barré syndrome) and these were considered coincidental unrelated events. CONCLUSIONS: There is no evidence of an increased rate of Guillain-Barré Syndrome with respect to the cases expected in the general population.

Six-month multicenter study on invasive infections due to Streptococcus pyogenes and Streptococcus dysgalactiae subsp. equisimilis in Argentina.

During a 6-month period, 95 invasive infections due to Streptococcus pyogenes and group C or group G Streptococcus dysgalactiae subsp. equisimilis were recorded from 40 centers of 16 cities in Argentina. We describe here epidemiologic data available for 55 and 19 patients, respectively, associated with invasive infections due to S. pyogenes and S. dysgalactiae subsp. equisimilis. The associated isolates and 58 additional pharyngeal isolates were genotyped and subjected to serologic and/or antibiotic susceptibility testing. Group A streptococcal emm type distribution and strain association with toxic shock appeared to differ somewhat from results found within the United States; however, serologic characterization and sof sequence typing suggested that emm types found in both countries are reflective of shared clonal types.

Resistencia de Streptococcus pyogenes a los antibióticos: Experiencia de once años en un hospital pediátrico de Buenos Aires / ANTIMICROBIAL RESISTANCE IN STREPTOCOCCUS PYOGENES. AN ELEVEN-YEAR SURVEILLANCE IN A PEDIATRIC HOSPITAL FROM BUENOS AIRES

En 1989 era escasa la preocupación acerca de la resistencia de Streptococcus pyogenes a los antibióticos habida cuenta de su sensibilidad universal a la penicilina. No obstante, algunos brotes puntuales en Japón y Australia de cepas resistentes a macrólidos en las décadas anteriores impulsaron a comenzar con la vigilancia de la resistencia de S. pyogenes a los antibióticos, primero en este hospital y luego en forma multicéntrica junto a otros centros de todo el país. En este trabajo se presentan los resultados de esta vigilancia, realizada durante once años (período 1989-2000). No se encontraron cepas resistentes ni con sensibilidad intermedia a penicilina en estreptococos del grupo A. Tampoco fue detectada resistencia a cloranfenicol ni a tetraciclina. La resistencia a eritromicina ascendió de un 0 - 2,0% a un 9,9% durante el período citado y ese aumento se debió principalmente a aislamientos que presentaban el fenotipo M (probable eflujo), algunos de los cuales demostraron poseer el genotipo mefA. En aislamientos de infecciones invasivas no se detectó resistencia a eritromicina. Al comparar la evolución de la resistencia a eritromicina entre 1990 y 2000 con el consumo nacional de macrólidos se pudo observar una tendencia similar a la publicada previamente por investigadores finlandeses.

Provided its universal susceptibility to penicillin, there was little interest about antimicrobial resistance in Streptococcus pyogenes before 1989. However, the knowledge about some outbreaks of erythromycin-resistant streptococci in Japan and Australia prompted us to begin a surveillance in the hospital and then as multicentre studies involving all the country. The results of such eleven-year surveillance (1989-2000) are being presented. Penicillin-resistant or intermediately-penicillin-susceptible group A streptococci were not found. Resistance to cloramphenicol or tetracycline was not detected. Erythromycin resistance changed from 0 - 2.0% to 9.9% along this period. These rates were due to the increasing isolation of streptococci showing the M phenotype (probably active efflux), some of them showing the mefA genotype. Among isolates obtained from invasive infections erythromycin resistance was not found. Comparing the evolution of erythromycin resistance with the national consumption of macrolides, a similar trend as that published by finnish authors was appreciated.

Erythromycin-resistant Streptococcus pyogenes in Argentina.

Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of growing concern all through the world. We are presenting the comparison of results of the continuous surveillance of erythromycin resistance in S. pyogenes performed since 1989 in the Hospital de Pediatría J.P. Garrahan of Buenos Aires City, with independently observed rates in other five centers of Buenos Aires and seven centers of six other Argentinian cities, obtained between 1999 and 2001. A significant increase of erythromycin resistance was observed among S. pyogenes isolated in the Hospital Garrahan (6.6% in 1998-1999 to 9.9% in 2000). Similar trends were also detected in other centers of other Argentinian cities when recent data were compared to results of a multicenter study performed in 1995. However, lower rates of resistance were recorded in Mendoza, Cipolletti and Neuquén in comparison with data of 1995, 1998 and 1998 respectively. The reason of such decreasing resistance rates deserves to be investigated. The average of ERY-resistance rates obtained in the surveyed centers was 6.7% (range 0.5-14.1%). Control of antimicrobial use should be performed to warrant the future effectiveness of macrolide antibiotics regarding the positive association between use and resistance. These results also suggest that susceptibility tests for macrolides should be performed whenever S. pyogenes is isolated in Argentina.

Erythromycin-resistant Streptococcus pyogenes in Argentina.

Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of growing concern all through the world. We are presenting the comparison of results of the continuous surveillance of erythromycin resistance in S. pyogenes performed since 1989 in the Hospital de Pediatría J.P.Garrahan of Buenos Aires City, with independently observed rates in other five centers of Buenos Aires and seven centers of six other Argentinian cities, obtained between 1999 and 2001. A significant increase of erythromycin resistance was observed among S. pyogenes isolated in the Hospital Garrahan (6.6

in 1998-1999 to 9.9

in 2000). Similar trends were also detected in other centers of other Argentinian cities when recent data were compared to results of a multicenter study performed in 1995. However, lower rates of resistance were recorded in Mendoza, Cipolletti and Neuquén in comparison with data of 1995, 1998 and 1998 respectively. The reason of such decreasing resistance rates deserves to be investigated. The average of ERY-resistance rates obtained in the surveyed centers was 6.7

(range 0.5-14.1

). Control of antimicrobial use should be performed to warrant the future effectiveness of macrolide antibiotics regarding the positive association between use and resistance. These results also suggest that susceptibility tests for macrolides should be performed whenever S. pyogenes is isolated in Argentina.

Six-month multicenter study on invasive infections due to group B streptococci in Argentina.

There is little information about invasive infections by group B streptococci (GBS) and their antimicrobial susceptibilities in Latin America. We performed a prospective multicenter study to determine the serotype distribution and the antimicrobial susceptibility of GBS in Argentina. We identified 58 cases, but only 44 had sufficient data to be evaluated. Eight early-, four late-, and one fatal late, late-onset neonatal infections due to GBS were found. A total of 31 patients were adults with bacteremia, skin and soft tissue infections, osteomyelitis, arthritis, meningitis, abdominal infections, and renal abscess. Serotype III was prevalent in late-onset neonatal disease, and several serotypes (Ia/c, III, Ia, and II) were involved in early-onset neonatal infections. Serotypes II, Ia/c, III, and IV were commonly found in adults, with serotype II prevalent in younger adults (18 to 69 years old) and serotype Ia/c prevalent in elderly adults (>70 years old). The mortality rate attributable to GBS infections was 10.8%. All GBS were susceptible to penicillin and ceftriaxone. Resistance to clindamycin (1.7%), erythromycin (5.2%), azithromycin (5.2%), minocycline (69%), and tetracycline (72.4%), to high levels of kanamycin and amikacin (1.7%), and to intermediately high levels of gentamicin (1.7%) was observed. The bifunctional enzyme AAC6'-APH2" was detected in the isolate resistant to aminoglycosides, and other genetic determinants were identified in other resistant isolates: tetM and tetO in tetracycline-resistant streptococci and mefA and ermTR for efflux-mediated and inducible macrolide-lincosamide-streptogramin B-resistant streptococci, respectively. For clinical purposes and rapid and easy detection of high-level aminoglycoside-resistant GBS, a screening method that used 1,000- micro g kanamycin disks is proposed.

Mielosupresión secundaria a bajas dosis de metotrexate / Secondary myelosupression at low dose methotrexate

El Metotrexate a altas dosis ha sido ampliamente utilizado en enfermedades oncológicas. Su uso se ha extendido a enfermedades inmunológicas, siendo en los últimos años el fármaco inmunomodulador más comúnmente utilizado como agente de segunda línea en enfermedades reumáticas. Dentro de los efectos secundarios se describen los hematológicos, siendo frecuente la aparición de trombocitopenia y la leucopenia y, poco común, la pancitopenia frente a bajas dosis del fármaco. En éste trabajo se presentan 4 casos clínicos de pacientes portadores de diferentes patologías autoinmunes, tratados con bajas dosis de Metotrexate durante un corto período de tiempo a pesar de lo cual presentan una pancitopenia como complicación. Se analizan los posibles mecanismos de mielotoxicidad vinculados a nuestros pacientes y los probables factores de riesgo para su desarrollo. Se comparan nuestros datos con los hallados en la bibliografía universal lo que nos reafirma su excepcionalidad (AU)

Mielosupresión secundaria a bajas dosis de metotrexate / Secondary myelosupression at low dose methotrexate

El Metotrexate a altas dosis ha sido ampliamente utilizado en enfermedades oncológicas. Su uso se ha extendido a enfermedades inmunológicas, siendo en los últimos años el fármaco inmunomodulador más comúnmente utilizado como agente de segunda línea en enfermedades reumáticas. Dentro de los efectos secundarios se describen los hematológicos, siendo frecuente la aparición de trombocitopenia y la leucopenia y, poco común, la pancitopenia frente a bajas dosis del fármaco. En éste trabajo se presentan 4 casos clínicos de pacientes portadores de diferentes patologías autoinmunes, tratados con bajas dosis de Metotrexate durante un corto período de tiempo a pesar de lo cual presentan una pancitopenia como complicación. Se analizan los posibles mecanismos de mielotoxicidad vinculados a nuestros pacientes y los probables factores de riesgo para su desarrollo. Se comparan nuestros datos con los hallados en la bibliografía universal lo que nos reafirma su excepcionalidad.

[DIAGNOSTIC AND THERAPEUTIC COLONOSCOPY IN PEDIATRICS] / Colonoscopía diagnótica y terapéutica en pediatría.

Gastrointestinal bleeding in childhood is an uncommon problem, althought when it happens it maybe an emergency. Upper bleeding predominates, and when we consider lower bleeding, the principal cause are polyps. Recent evidence points out that polyps are responsible for bleeding in 77% of cases.We decided to study the clinical course, histologic characteristics and treatment in children with lower gastrointestinal bleeding. This investigation was held at Edgardo Rebagliati National Hospital during 1990 to 1996. Inclusion criteria were: younger than 14 years, gastrointestinal bleeding, and colonoscopy exam.100 colonoscopies were done in 74 children. Polyps were the cause for gastrointestinal bleeding in 71.6% of cases. In 14 children more than one colonoscopy was done. More than one polyp in 16 children were found. Ulcerative colitis was diagnosed in two cases, and intestinal tuberculosis in other two cases. Average age was 8.8 years, and 100% presented rectorragia and anemia.Polyps were located principally in rectum and sigmoid. Polipectomy was done in 94.34% of the cases, and it was technically succesful. We had only one complication (snare wire was trapped) but with no morbidity.Histological examination demonstrated that juvenile polyp was the most frequent type (56.66%), followed by tubular adenoma (11.32%), and Peutz-Jegher polyp in 3.77%. Treatment was polipectomy in all cases. Eleven procedures were done in the surgical room, and 19 in the endoscopy unit, with no complications in any of the cases.CONCLUSION: In children the main cause for lower gastrointestinal bleeding are polyps. All cases present with rectorragia or anemia, and juvenile polyps are the most frequent type. Colonoscopy is a safe method for diagnosis and treatment, which can be done in the endoscopy unit with mild sedation and with an anesthesist or pediatrician as assistants.

Streptococcus pyogenes: sensibilidad a penicilina y eritromicina en las ciudades de Neuquen y Cipolletti / Streptococcus pyogenes: penicillin and erythromycin susceptibility in the cities of Neuquen and Cipolletti

Hasta la fecha no se ha detectado resistencia a penicilina en Streptococcus pyogenes. No obstante se ha registrado un aumento en la resistencia a macrólidos en varios países del mundo. En la Argentina se han observado escasos porcentajes de resistencia a eritromicina, a excepción de un 11.1 por ciento registrado en Mendoza. El objetivo del presente trabajo fue estudiar la sensibilidad in vitro a penicilina y eritromicina de 251 aislamientos sucesivos de S. pyogenes obtenidos en cuatro centros asistenciales localizados en las ciudades de Neuquén y Cipolletti durante el período abril-diciembre de 1998. Se empleó el método de difusión con discos de penicilina y el método del doble disco (eritromicina 15 Ag y clindamicina 2 Ag) para observar la resistencia a macrólidos y el mecanismo involucrado. Los aislamientos resistentes a macrólidos fueron estudiados por E-test (AB Biodisk, Solna, Suecia) para establecer los niveles de sensibilidad a eritromicina, y por dilución en agar para penicilina, eritromicina, ceftriaxona, azitromicina y clindamicina. Todos los aislamientos fueron sensibles a penicilina y treinta de ellos (12.0 por ciento) fueron resistentes a eritromicina. Estos últimos mostraron el fenotipo M, característico del mecanismo de eflujo activo. Todos los aislamientos resistentes a eritromicina (CIM entre 8 y 16 mg/l) también resultaron resistentes a azitromicina, pero sensibles a clindamicina, penicilina y ceftriaxona. De acuerdo a estos resultados concluimos que S. pyogenes continúa siendo sensible a la penicilina, pero creemos que en nuestra zona es necesario realizar estudios rutinarios de pruebas de sensibilidad a macrólidos debido al relativamente elevado porcentaje de resistencia a eritromicina observado. (AU)

Streptococcus pyogenes: sensibilidad a penicilina y eritromicina en las ciudades de Neuquen y Cipolletti / Streptococcus pyogenes: penicillin and erythromycin susceptibility in the cities of Neuquen and Cipolletti

Hasta la fecha no se ha detectado resistencia a penicilina en Streptococcus pyogenes. No obstante se ha registrado un aumento en la resistencia a macrólidos en varios países del mundo. En la Argentina se han observado escasos porcentajes de resistencia a eritromicina, a excepción de un 11.1 por ciento registrado en Mendoza. El objetivo del presente trabajo fue estudiar la sensibilidad in vitro a penicilina y eritromicina de 251 aislamientos sucesivos de S. pyogenes obtenidos en cuatro centros asistenciales localizados en las ciudades de Neuquén y Cipolletti durante el período abril-diciembre de 1998. Se empleó el método de difusión con discos de penicilina y el método del doble disco (eritromicina 15 µg y clindamicina 2 µg) para observar la resistencia a macrólidos y el mecanismo involucrado. Los aislamientos resistentes a macrólidos fueron estudiados por E-test (AB Biodisk, Solna, Suecia) para establecer los niveles de sensibilidad a eritromicina, y por dilución en agar para penicilina, eritromicina, ceftriaxona, azitromicina y clindamicina. Todos los aislamientos fueron sensibles a penicilina y treinta de ellos (12.0 por ciento) fueron resistentes a eritromicina. Estos últimos mostraron el fenotipo M, característico del mecanismo de eflujo activo. Todos los aislamientos resistentes a eritromicina (CIM entre 8 y 16 mg/l) también resultaron resistentes a azitromicina, pero sensibles a clindamicina, penicilina y ceftriaxona. De acuerdo a estos resultados concluimos que S. pyogenes continúa siendo sensible a la penicilina, pero creemos que en nuestra zona es necesario realizar estudios rutinarios de pruebas de sensibilidad a macrólidos debido al relativamente elevado porcentaje de resistencia a eritromicina observado.

Hemobilia: reporte de dos casos / Hemobilia: report of two cases

La hemobilia, definida como hemorragia dentro del árbol biliar, es una entidad rara. La comunicación anormal entre los vasos sanguíneos y el árbol biliar puede ser debida a trauma, desórdenes inflamatorios, infecciones, litiasis vesicular, tumores y trastornos de la coagulación. Presentamos el reporte de dos casos, cuyo diagnóstico se realizó por Pancreatocolangiografía Retrógrada Endoscópica (PCRE).

Hemobilia is defined as the hemorrhage within the biliary tree. Maybe, the abnormal communication between blood vessels and the biliary tree, is due to trauma, inflammatory disorders, infections, gallstones, tumors and coagulation disorders. Two cases, which diagnosis were made with retrograde endoscopic cholangio pancreatography, are reported here.

[HEMOBILIA: REPORT OF TWO CASES] / Hemobilia: Reporte de Dos Casos.

Hemobilia is defined as the hemorrhage within the biliary tree. Maybe, the abnormal communication between blood vessels and the billiary tree, is due to trauma, inflammatory disorders, infections, gallstones, tumors and coagulation disorders. Two cases, which diagnosis were made with retrograde endoscopic cholangio pancreatography, are reported here.