Incorporación del test rápido para VIH y sífilis en consultorio de enfermedades de transmisión sexual / Incorporación del test rápido para VIH y sífilis en consultorio de enfermedades de transmisión sexual

INTRODUCCIÓN Las infecciones por el virus de la inmunodeficiencia humana (VIH) y Treponema pallidum, agente causal de sífilis, comparten ­aunque con importantes diferencias­ vías de transmisión (sexual, parenteral y vertical). La incorporación de test rápidos (TR) para ambos agentes podría ser de gran utilidad para acelerar el acceso de los pacientes al diagnóstico, así como su incorporación al sistema de salud. OBJETIVOS Evaluar el impacto de la implementación de TR sobre la aceptabilidad del diagnóstico de VIH y T. pallidum en el consultorio del Programa de Enfermedades de Transmisión Sexual (PETS). MÉTODOS Entre marzo y diciembre de 2015 se ofreció a todos los pacientes que concurrieron al PETS la realización de TR para VIH y sífilis a partir de punción digital. Se realizaron estudios complementarios según resultados de TR ELISA HIV, carga viral, recuento de CD4, VDRL y FTA-Abs. RESULTADOS Se realizó un total de 583 TR para VIH y 586 TR para sífilis. Se observó una prevalencia de VIH por TR del 5,8%, con confirmación de la infección en el 93,8% y 2 casos de falsos reactivos. En el año previo al estudio, el 6,9% de los pacientes aceptaron realizarse test de VIH, con un incremento del 30,9% (p<0,001). El 84,1% de los pacientes se realizaron VDRL luego del TR para sífilis, con una frecuencia más alta en los pacientes con TR reactivos (94,3% frente a 79,8%, p<0,001). La prevalencia de sífilis según el TR fue del 33,7% y la de sífilis activa (TR reactivo/VDRL reactiva) del 25,1%, con un incremento respecto al año previo del estudio de 11,4% (p<0,001). Discusión Este estudio suma evidencia sobre las ventajas del uso de TR en pacientes vulnerables para la adquisición de VIH y sífilis. La implementación del TR aumentó la cantidad de diagnósticos de VIH y sífilis. En cuanto a la evaluación del TR para sífilis, se resalta su utilidad en una población de alta prevalencia, pero también la importancia de la evaluación médica en conjunto con resultados de VDRL para identificar pacientes que necesitan tratamiento.

First case report of Toxoplasma gondii-induced abortions and stillbirths in sheep in Argentina.

The aim of this study is to report an episode of reproductive losses due to toxoplasmosis in a sheep flock in Argentina. A total of 15 abortions and 9 stillbirths were recorded in a flock of 190 Texel ewes. The affected ewes were more likely to be seropositive for Toxoplasma gondii (15/24) than ewes that delivered normal lambs (5/34, OR=9.6, 95%CI=2.7-34.0, p=0.0004). A pair of aborted twins was recovered for diagnostic investigation. One of these fetuses and its dam were seropositive for T. gondii. Histological examination of the two fetuses revealed non-suppurative myocarditis and epicarditis, portal hepatitis and multifocal necrotizing encephalitis with protozoal cysts in the brain. T. gondii was detected intralesionally by immunohistochemistry in one fetus and by PCR in both. Further investigations are necessary to evaluate the economic losses due to T. gondii in the Argentinean ovine industry.

Brain derived neurotrophic factor and neurotrophin-4 employ different intracellular pathways to modulate norepinephrine uptake and release in rat hypothalamus.

Classical actions of the neurotrophin family are related to cellular survival and differentiation. Moreover, acute effects of neurotrophins have been reported. Although neurotrophins effects on synaptic transmission at central nervous system level have been largely studied, acute effects of neurotrophins on hypothalamic noradrenergic transmission are still poorly understood. Thus, we have studied the effects of the neurotrophin family members nerve growth factor (NGF), brain derived neurotrophic factor (BDNF) and neurotrophin-4 (NT-4) on norepinephrine (NE) neuronal uptake and its evoked release, as well as the receptor and the intracellular pathways involved in these processes in rat hypothalamus. Present results indicate that BDNF increased NE uptake and decreased its evoked release through a mechanism that involve Trk B receptor and phospholipase C. Moreover, NT-4, also through the Trk B receptor, decreased NE uptake and its evoked release by activating phosphatidylinositol 3-OH-kinase. These effects were observed in whole hypothalamus as well as in the anterior hypothalamic zone. On the other hand, NGF did not modify noradrenergic transmission. In conclusion, we showed for the first time that BDNF and NT-4 activate two different intracellular signalling pathways through a Trk B receptor dependent mechanism. Furthermore, present findings support the hypothesis that BDNF and NT-4 acutely applied, could be considered as modulators of noradrenergic transmission and thus may regulate hypothalamic physiological as well as pathophysiological responses.

Oral treatment and in vitro incubation with fructose modify vascular prostanoid production in the rat.

1.-- In the rat, a fructose-enriched diet induces hyperglycaemia, hypertriglyceridaemia, insulin resistance and hypertension; a model which resembles the human metabolic syndrome. 2.-- Prostanoids, metabolites of arachidonic acid, include vasoactive substances synthesized and released from the vascular wall that have been implicated in the increase of peripheral resistance, one of the mechanisms involved in the fructose-induced hypertension. 3.-- The aim of the present study was to: (i) analyse the effects of the in vitro incubation with fructose on the production and release of prostanoids in rat thoracic aorta and in rat mesenteric bed and (ii) compare the effects of incubation with those of the in vivo acute and chronic treatment of rats with fructose and with the combination of both in vivo and in vitro procedures. 4.-- Blood pressure, glycaemia and triglyceridaemia were significantly elevated in both 4- and 22-week fructose-treated groups. Meanwhile, body and heart weight as well as insulinaemia were similar between experimental animals and controls. 5.-- In aortae, 4 weeks of Fructose treatment did not modify the prostanoid pattern release, but in vitro incubation decreased prostacyclin (PGI(2)) production. However, after 22 weeks, fructose treatment and incubation exerted the same effect. 6.-- In mesenteric bed, after 4 weeks, the incubation and the combination of both procedures reduced the release of the vasodilators PGI(2) and PGE(2), while fructose treatment only diminished the PGE(2) release. On the contrary, the production of the vasoconstrictor thromboxane A(2) (TXA(2)) was enhanced by incubation and both the procedures. After 22 weeks, fructose treatment increased PGI(2) release, while it was reduced by incubation. The combination of both did not modify this peripheral resistance when compared with controls. Finally, incubation of tissues from treated rats increased the release of the vasoconstrictors, PGF(2alpha) and TXA(2). 7.-- In conclusion, the mesenteric bed, a resistance vascular bed, seems to be more sensitive than the aorta, a conductance vessel, to the effects of fructose on prostanoid production. This difference could be related to a more relevant role of resistance vessels in the regulation of peripheral resistance and consequently of blood pressure. The observed effects should contribute to a shift in the balance of the release of prostanoid in favour of vasoconstrictor metabolites. This phenomenon could be related to an increase in the peripheral resistance and the mild hypertension observed in the fructose-treated rats.

Antimicrobial susceptibility of coagulase-negative staphylococci isolated from bovine mastitis in Argentina.

A total of 123 isolates of coagulase-negative staphylococci isolated from bovine clinical and subclinical mastitis in Argentina from March 1998 to March 2000 was investigated for in vitro susceptibility to several antimicrobial agents. Minimum inhibitory concentrations that inhibit 90% of the isolates tested (reported in micrograms per milliliter) were: 4.40, 0.38, 4.00, 0.75, 0.75, 3.60, and 2.00 for penicillin, oxacillin, cephalothin, gentamicin, erythromycin, clindamycin, and ampicillin-sulbactam, respectively. Resistance was detected in 34 (27.6%), 4 (3.2%), 7 (5.7%), and 6 (4.8%) isolates for penicillin, oxacillin, erythromycin, and pirlimycin, respectively. No resistance was detected for gentamicin, cephalothin, or ampicillin-sulbactam. Results indicated that coagulase-negative staphylococci isolates in Argentina exhibited the highest degree of resistance to penicillin of all antimicrobial agents tested.

Incidence of Chlamydia trachomatis and other potential pathogens in neonatal conjunctivitis.

OBJECTIVE: Ocular infection in neonatology is a permanent and important health problem. To improve primary attention, prevention, and control, the study of the potential bacterial etiology of all consecutive cases of conjunctivitis was incorporated as a regular procedure in primary care from July 1995 to December 1998. MATERIALS AND METHODS: Prof. A. Posadas Hospital (Great Buenos Aires) has an average of 4294 births per year. This report analyzes the results obtained in 332 infants (age range, 0-30 d) with conjunctivitis. Clinical conjunctivitis was diagnosed in inpatients and outpatients by the same specialized staff. Isolation and characterization of bacteria were done by conventional microbiologic methods, including specific search for Neisseria gonorrhoeae and Chlamydia trachomatis. Chlamydia trachomatis was studied by antigen immunodetection and polymerase chain reaction, and genotyped by restriction fragment length polymorphism. RESULTS: Conjunctivitis had an incidence (cases per 1000 live births) of 39.6 in 1995, 25.3 in 1996, 15.4 in 1997, and 15.2 in 1998. Microbial growth was detected in 167 (50.3%) of 332 cases. Ocular C. trachomatis infection was detected in 26 cases (7.83%). Five of seven isolates in tissue cultures belonged to type E and two to type G. Bacteria from respiratory ecology were the main isolates: Haemophilus influenzae (16.9%), Streptococcus pneumoniae (12.3%), and Staphylococcus aureus (8.7%). Haemophilus influenzae isolates were not serotyped and 17.2% of them were b-lactamase producers. In 15 cases both H. influenzae and S. pneumoniae were isolated together. Of S. pneumoniae, 4.9% were oxacillin resistant. CONCLUSIONS: There has been a decline in the total number of cases of neonatal conjunctivitis, but the disease is still an important health problem. Chlamydia trachomatis also shows a decreasing profile with an incidence of (cases per 1000 live births) 4.39 in 1995, 1.85 in 1996, 1.01 in 1997, and 0.78 in 1998, and a tendency to show more incidence in spring-summer and significant accumulation of cases in babies between 7 and 9 days of age. Haemophilus influenzae alone (12.3%) or associated with S. pneumoniae (4.5%) appears as a prevalent potential bacterial pathogen. A significant accumulation of H. influenzae and S. pneumoniae cases occurs in winter. In 47.6% of cases, there was no bacterial growth. No significant seasonal differences in percentage of negative cultures or among the three-day age groups were detected. Neisseria gonorrhoeae was not found associated with ophthalmia neonatorum in this series.

Angiotensin-(1-7) does not affect norepinephrine neuronal uptake or catabolism in rat hypothalamus and atria.

1. Since we previously reported that angiotensin-(1-7) [Ang-(1-7)] increases or inhibits norepinephrine (NE) release in rat atria or hypothalamus, respectively, the present work was undertaken to investigate the effect of the heptapeptide on NE neuronal uptake and metabolism in atria and hypothalamus isolated from rats. 2. Ang II (1-10 microM) caused a decrease in neuronal NE uptake in both atria and hypothalami isolated from rats. On the contrary, tissues incubated with [3H]NE in the presence of 0.1-10 microM Ang-(1-7) showed no modification in [3H]NE content with respect to the control group, suggesting that the heptapeptide did not modify [3H]NE neuronal uptake. 3. To study the effect of the heptapeptide on NE catabolism, monoamine-oxidase (MAO) and catechol-O-methyltransferase (COMT) activities were determined. Pretreatment of the tissue with Ang-(1-7) (0.1-1.0 microM) showed a tendency to diminish MAO activity in rat atria, while no significant changes were observed in hypothalamic MAO activity. Moreover, the heptapeptide (0.1-1.0 microM) did not affect central COMT activity with respect to the control group. 4. Present results allow us to conclude that Ang-(1-7) interacts with noradrenergic neurotransmission by increasing or inhibiting NE release at the peripheral and central levels, respectively, without affecting either the neurotransmitter neuronal uptake or catabolism.

Angiotensin-(1-7) reduces norepinephrine release through a nitric oxide mechanism in rat hypothalamus.

Angiotensin (Ang)-(1-7) elicits a facilitatory presynaptic effect on peripheral noradrenergic neurotransmission, and because biological responses to the heptapeptide on occasion are tissue specific, the present investigation was undertaken to study its action on noradrenergic neurotransmission at the central level. In rat hypothalamus labeled with [(3)H]-norepinephrine, 100 to 600 nmol/L Ang-(1-7) diminished norepinephrine released by 25 mmol/L KCl. This effect was blocked by the selective angiotensin type 2 receptor antagonist PD 123319 (1 micromol/L) and by the specific Ang-(1-7) receptor antagonist ([D-Ala(7)]Ang-(1-7) (1 micromol/L) but not by losartan (10 nmol/L to 1 micromol/L), a selective angiotensin type 1 receptor antagonist. The inhibitory effect on noradrenergic neurotransmission caused by Ang-(1-7) was prevented by 10 micromol/L N(omega)-nitro-L-arginine methylester, an inhibitor of nitric oxide synthase activity, and was restored by 100 micromol/L L-arginine, precursor of nitric oxide synthesis. Methylene blue (10 micromol/L), an inhibitor of guanylate cyclase considered as the target of nitric oxide action, as well as Hoe 140 (10 micromol/L), a bradykinin B(2)-receptor antagonist, prevented the inhibitory effect of the heptapeptide on neuronal norepinephrine release, whereas no modification was observed in the presence of 0.1 to 10 micromol/L indomethacin, a cyclooxygenase inhibitor. Our results indicate that Ang-(1-7) has a tissue-specific neuromodulatory effect on noradrenergic neurotransmission, being inhibitory at the central nervous system by a nitric oxide-dependent mechanism that involves angiotensin type 2 receptors and local bradykinin production.

Comparative in-vitro activity of moxifloxacin, minocycline and azithromycin against Chlamydia spp.

The in-vitro activity of moxifloxacin, a new 8-methoxyquinolone, was compared with minocycline and azithromycin against 40 strains of Chlamydia trachomatis, Chlamydia pneumoniae and Chlamydia psittaci. Both the MIC and the MBC of moxifloxacin ranged from 0.03 to 0.125 mg/L. MICs of minocycline ranged from 0.015 to 0.06 mg/L and MBCs between 0.03 and 0.25 mg/L. MICs of azithromycin ranged from 0.03 to 0.125 mg/L and the MBCs between 0.06 and 0.5 mg/L. MBC values of moxifloxacin were the same as MICs in 32 (80%) of 40 strains tested, whereas those of minocycline and azithromycin were two to four times higher than their MICs. These data confirm those previously obtained indicating that quinolones kill chlamydial strains at concentrations equivalent to their MICs.

Norepinephrine uptake modifications in circumventricular organs, pons and myelencephalic areas and nuclei in prehepatic portal hypertensive rats.

Peripheral noradrenergic activity is enhanced in portal hypertension and correlates with the progression of the disease. However, little is known about the status of central norepinephrine (NE) in portal hypertension. The aim of the present work was to study the uptake of NE in several areas rich in NE in experimental prehepatic portal hypertension. The experiments were performed in vitro in several encephalic areas and nuclei, obtained according to the 'punch-out technique'. Results showed that in portal hypertensive rats NE uptake enhanced in all areas and nuclei studies (subfornical organ, organum vasculosum lamina terminalis, area postrema, locus coeruleus and nucleus tractus solitarius). The present results suggest that these encephalic areas and brainstem nuclei may be related to the development and/or maintenance of portal hypertension in this animal model.

[Syphilis in adolescent mothers in the city of Posadas, Province of Misiones]. / Sifilis en madres adolescentes en la ciudad de Posadas, Provincia de Misiones.

During three months (April to June 1997) 1,238 consecutive pregnant women were studied at the time of delivery at the Madariaga public Hospital. Syphilis was confirmed in 26 (2.1%) women, and 15 cases (57.7%) of congenital syphilis were demonstrated in newborns one of whom was a stillborn. Of the syphilitic women 61.5% were 20 years old (average), 65.4% were single, 19.2% had a stable partner and 15.4% were married; 70% of them had finished elementary school (seven years), but despite this discrete level of instruction and that they were benefited with free health attention, 73% of them had not started or completed the pregnancy control. None of these women acted as sexual workers or were drug users; 57.7% were unemployed and the remainder worked as domestic servants or were still going to school. Menarca started at 13 (average) and the age of the first sexual activity was 15 (average). The distribution of the cases of syphilis within the city area shows four clusters that coincide with the lower income population, but not with marginal groups. The failure to submit to medical control during pregnancy among syphilitic women is directly linked with an increased risk for congenital syphilis. The specific prevalence of syphilis in women (20 years old or less) pregnant or not, shows an alarming hidden epidemic situation. An interinstitutional and communitary program, with direct interventions within the detected population clusters, is now underway in order to control syphilis. Undesired pregnancy and syphilis seem to be associated with adolescent unsafe sex conducts. A coordinated program between Public Health Service and National Misiones University is operating, visiting home by home, in order to decrease or eliminate congenital syphilis and is considered a priority health problem. Unfortunately, if sexual conducts do not undergo changes in the near future, at least by the correct use of condoms, HIV will replace syphilis.

Atrial natriuretic factor inhibits norepinephrine biosynthesis and turnover in the rat hypothalamus.

We have previously reported that atrial natriuretic factor (ANF) increased neuronal norepinephrine (NE) uptake and reduced basal and evoked neuronal NE release. Changes in NE uptake and release are generally associated to modifications in the synthesis and/or turnover of the amine. On this basis, the aim of the present work was to study ANF effects in the rat hypothalamus on the following processes: endogenous content, utilization and turn-over of NE; tyrosine hydroxylase (TH) activity; cAMP and cGMP accumulation and phosphatidylinositol hydrolysis. Results showed that centrally applied ANF (100 ng/microl/min) increased the endogenous content of NE (45%) and diminished NE utilization. Ten nM ANF reduced the turnover of NE (53%). In addition, ANF (10 nM) inhibited basal and evoked (with 25 mM KCl) TH activity (30 and 64%, respectively). Cyclic GMP levels were increased by 10 nM ANF (100%). However, neither cAMP accumulation nor phosphatidylinositol breakdown were affected in the presence of 10 nM ANF. The results further support the role of ANF in the regulation of NE metabolism in the rat hypothalamus. ANF is likely to act as a negative putative neuromodulator inhibiting noradrenergic neurotransmission by signaling through the activation of guanylate cyclase. Thus, ANF may be involved in the regulation of several central as well as peripheral physiological processes such as cardiovascular function, electrolyte and fluid homeostasis, endocrine and neuroendocrine synthesis and secretion, behavior, thirst, appetite and anxiety that are mediated by central noradrenergic activity.

Norepinephrine uptake is enhanced in discrete telencephalic and diencephalic areas and nuclei in prehepatic portal hypertensive rats.

Several evidences support the hypothesis that central catecholamines may play a significant role in the production and/or maintenance of different alterations that characterize portal hypertension. The aim of the present work was to study the possible modifications in norepinephrine (NE) metabolism in several telencephalic and diencephalic areas rich in NE in experimental prehepatic portal hypertension. NE uptake was studied as an index of NE metabolism. The experiments were carried out in vitro in encephalic areas and nuclei, obtained according to the punch-out technique. Results indicated that portal hypertensive rats showed an enhancement of NE uptake in olfactory bulb (OB), preoptic area (PA), and supraoptic, periventricular, paraventricular, and arcuate nuclei (SON, PeVN, PaVN, and AN, respectively) compared to sham-operated rats. However, no modifications on NE uptake was observed in the median eminence (ME). Present results suggest that the changes observed in central NE uptake may be related to the development and/or maintenance of the portal hypertensive state.

[Extent of endemic Chlamydia trachomatis in the metropolitan area of Buenos Aires (Argentina)]. / Dimensión de la endemia por Chlamydia trachomatis en el área de la ciudad de Buenos Aires (Argentina).

BACKGROUND: In this report we inform laboratory results accumulated over ten years (1986-1995). The number of cases, and the geographic distribution, allow us to present a very reliable data about the dimension of Chlamydia trachomatis urogenital infections in Buenos Aires city and we also compare this profile with the prevalence of Neisseria gonorrhoeae in the same area and period of time. METHODS: Patients were females and males (aged from 15 to 49 years old) attending clinics not specialize in Sexually Transmitted Diseases (STD). Intent to isolation of C. trachomatis was done in McCoy cells culture. Patients for Neisseria gonorrhoeae investigation were a population assisted at the Clinic for STD of an University Hospital (aged from 15 to 75 years old). Study for detection of N. gonorrhoeae was developed by direct and conventional culture technics. RESULTS: 4128 endocervical samples from women with lower genital tract pathology were studied and C. trachomatis infection was detected in 25.6 +/- 4.8%. Over 1206 male urethral samples 29.5 +/- 4.47% shows positive cultures. Except for years 1989 and 1990 in which annual percentage of infected women showed slightly higher percentage over the global average, the results shows a very stable annual values, as it was also found in male patients. Infection in males shows a discrete tendency to be higher compare with values obtained in women. Global results of the evolution of prevalence of N. gonorrhoeae infection shows a very different pattern. Since 1992 we demonstrate a very significant decrease in the number of confirmed cases. CONCLUSIONS: We concluded that patients not attending a STD clinic, reveal a high and very stable endemic level of C. trachomatis lower tract urogenital infections. N. gonorrhoeae in this population is a very sporadic or null finding. Prevalence of Chlamydial infection in STD centers is even higher and also shows an stable profile. In people attending STD clinics N. gonorrhoeae shows a very different kinetics, with an important decrease in prevalence in the last five years.