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M Portús

Publications and source records attributed to M Portús.

At least 19 recordsLinked to original sources
PubMed2004

Evaluation of a latex agglutination test (KAtex) for detection of Leishmania antigen in urine of patients with HIV-Leishmania coinfection: value in diagnosis and post-treatment follow-up.

The usefulness of antigen detection in urine as an alternative tool for diagnosis of leishmaniasis and post-treatment follow-up in patients with Leishmania-HIV coinfection was evaluated with a latex agglutination test (KAtex; Kalon Biological, UK). Forty-nine HIV-infected patients with visceral leishmaniasis were included in the study. Antigen detection in urine (ADU) was positive in 42 of 49 (sensitivity, 85.7%) samples obtained during a primary episode. After treatment, a follow-up study in 23 patients was performed by simultaneous ADU and culture of peripheral blood mononuclear cells in 148 determinations. The two methods gave concordant results in 94 cases, 38 of which were positive and 56 negative. In five cases, ADU was negative and culture of peripheral blood mononuclear cells was positive: two of these cases corresponded to clinical relapses. In 49 cases, culture of peripheral blood mononuclear cells was negative and ADU was positive. In the absence of clinical symptoms, the detection of parasite antigens in 71 of 130 (54.6%) urine samples was not associated with clinical disease. The Kaplan-Meier estimates of the probability of relapse at 6, 12, 18, and 24 months were 16% (95%CI, 15-17%), 20% (95%CI, 18-22%), 31% (95%CI, 27-35%), and 71% (95%CI, 52-89%), respectively, in patients with a positive ADU result. In contrast, when ADU was negative, the probability of relapse was 5% at 6 months (95%CI, 2-8%) (only 2 of 11 patients who relapsed had a negative test). ADU by KAtex is appropriate for primary diagnosis of visceral leishmaniasis, for monitoring the efficacy of treatment, and for detection of subclinical infection.

AIDS-Related Opportunistic Infections↗
PubMed2003

Detection of anti-Leishmania immunoglobulin G antibodies in urine specimens of dogs with leishmaniasis.

For years, anti-Leishmania immunoglobulin G (IgG) antibodies have been detected in the sera of dogs living in areas of leishmaniasis endemicity. They have also been found in the aqueous humor and cerebrospinal fluid. In contrast, a review of the literature failed to identify the detection of anti-Leishmania antibodies in urine samples from dogs with leishmaniasis. Ninety-five dog urine samples were examined for the presence of anti-Leishmania antibodies by using a protein A enzyme-linked immunosorbent assay (ELISA). Twenty additional urine samples were collected from healthy dogs as controls. An IgG2 ELISA was performed on 26 urine samples found positive by the protein A ELISA. Twenty-three urine samples found positive to anti-Leishmania antibodies were tested for the local production of anti-Leishmania antibodies in the urinary tract by means of the urine antibody coefficient. Ten urine samples (and the corresponding serum samples) were compared by Western blot (WB) analysis. Thirty-five out of the 95 urine samples were found positive, 57 were found negative, and 3 were found inconclusive for antibody detection by the protein A ELISA. A high correlation between protein A and IgG2 levels was found in positive urine samples. Anti-Leishmania antibodies were present in the urine of dogs that had leishmaniasis, urinary protein/creatinine (U P/C) ratios of greater than one, and normal urinary sediment. A statistically significant correlation was observed between the U P/C ratios and the levels of anti-Leishmania antibodies in positive urine samples. In general, WB analysis and the urine antibody coefficient suggested that the presence of anti-Leishmania antibodies in urine was the consequence of an impairment of filtration of the glomerular barrier. However, in some dogs, WB analysis could be interpreted as suggesting that the presence of anti-Leishmania antibodies was caused, to a lesser extent, by local antibody production in the urinary tract. Antibody detection in urine could be a noninvasive method for leishmaniasis diagnosis and prognosis in dogs with glomerulonephropathies.

Animals↗
PubMed2002

A nested polymerase chain reaction for diagnosis and follow-up of human visceral leishmaniasis patients using blood samples.

A nested polymerase chain reaction (PCR) assay for the diagnosis of human visceral leishmaniasis (VL) due to Leishmania infantum infection was developed using primers selected from the parasite's genomic deoxyribonucleic acid (DNA). The assay, which is based on the use of leucocytes separated from blood samples by Ficoll-Paque centrifugation, was compared with culture in vitro. Blood samples were collected from 17 patients in Spain with a history of clinical VL, 15 of whom were also infected with human immunodeficiency virus (HIV) (13 samples during the VL episode and 31 samples during post-treatment monitoring) and one sample was collected from each of 28 patients with HIV infection and fever but no history of VL. The nested PCR using blood detected all the cases of parasitologically confirmed, clinically active VL, while culture detected 92%. The nested PCR detected Leishmania DNA in 18% of the HIV-infected patients with fever and no history of VL, none of whom gave a positive culture. Follow-up examination of the VL patients by nested PCR and culture demonstrated the persistence of L. infantum in blood for a long time after treatment.

AIDS-Related Opportunistic Infections↗
PubMed2001

Nested PCR for diagnosis of canine leishmaniosis in peripheral blood, lymph node and bone marrow aspirates.

A nested polymerase chain reaction (PCR) assay was developed using primers selected from the genomic DNA of Leishmania infantum and applied to the diagnosis of leishmaniosis in peripheral blood in dogs. Blood of 39 dogs of different breeds, all sampled in Catalonia (Spain), were tested for leishmaniosis by enzyme linked immunosorbent assay (ELISA), western blotting (WB) and peripheral blood mononuclear cell (PBMC) culture and nested PCR. Twenty negative controls (healthy dogs less than 1-year-old that had not been exposed to a sandfly season) were also studied. Nineteen of the 39 dogs studied were positive by ELISA and/or WB, and 18 of these had a positive PBMC nested PCR. PBMC nested PCR was negative in all the remaining animals that were negative by serological examination, including the 20 negative controls. Parasitological examination and nested PCR of bone marrow and lymph node aspirate from the 19 dogs positive by serological examination, were also positive. These results indicate that PBMC nested PCR is a sensitive and specific tool to diagnose leishmaniosis in dogs. The use of PBMC has the advantage over bone marrow and lymph node aspirates in that it is a less invasive sample.

Animals↗
PubMed2001

Long term improvement in the treatment of canine leishmaniosis using an antimony liposomal formulation.

Pharmacokinetic and clinical effectiveness of liposome-encapsulated N-methylglucamine antimoniate (LMA) was performed in dogs suffering from experimental leishmaniosis. LMA was compared with N-methylglucamine antimoniate (MGA), the same drug in its free form. Sb plasma concentrations for LMA were always higher than those for MGA. Mean residence time (MRT), half-life time (t(1/2)) and clearance (Cl) showed that Sb was eliminated slower after liposome administration. The high volume of distribution (Vd) obtained with LMA suggests that Sb could achieve therapeutic concentrations in parasite-infected tissues. Average plasma concentration at steady state (Css(ave)) shows that Sb body concentrations after LMA treatment (9.8 mg/kg Sb, each 24h) would be effective in Leishmania infantum canine infection. Comparing LMA with MGA in a 1-year follow-up we observed no relapses for LMA and total protein and gammaglobulin concentrations were within normal range, while for MGA both began to rise 3 months after treatment. Use of antimonial liposomal formulations may restore effectiveness to an existing drug and reduce toxicity.

Animals↗
PubMed2001

Leishmania infantum-specific IgG, IgG1 and IgG2 antibody responses in healthy and ill dogs from endemic areas. Evolution in the course of infection and after treatment.

The expression of IgG, IgG1 and IgG2 specific antibodies for Leishmania infantum was studied in five groups of dogs in Catalonia (Spain): I, 99 asymptomatic dogs (infected and uninfected) from a highly endemic area for leishmaniosis; II, 139 untreated dogs with clinically patent leishmaniosis; III, 11 naturally infected asymptomatic dogs monitored for up to 5 years since they were found seropositive to Leishmania antigen and without treatment; IV, 25 naturally infected dogs with clinically patent leishmaniosis and treated with either meglumine antimoniate and allopurinol or allopurinol alone and V, six experimentally infected dogs, treated with meglumine antimoniate and controlled for 5 years. The levels (ELISA units) of IgG, IgG1 and IgG2 in asymptomatic dogs (group I) were very variable (24+/-33, 32+/-31 and 26+/-31, respectively), and, as expected, lower than in ill dogs (group II) (168+/-34, 84+/-71 and 172+/-31, respectively). In both groups, the correlation between IgG and IgG2 levels (r=0.95, P<0.001 in group I and r=0.63, P<0.001 in group II) was higher than between IgG and IgG1 levels (r=0.01, P>0.05 in group I and r=0.31, P<0.001 in group II). In group III, IgG and IgG2 expression increased during infection, while IgG1 expression remained the same. In dogs of group IV, IgG levels after 1 year of treatment decreased more in responsive (mean values, 163+/-42 before treatment (b.t.) and 100+/-36 after treatment (a.t.)) than in unresponsive dogs (158+/-29 b.t. and 124+/-51 a.t.), especially for IgG1 (94+/-89 b.t. and 20+/-21 a.t. in responsive dogs and 35+/-25 b.t. and 22+/-13 a.t. in unresponsive dogs) rather than for IgG2 (156+/-16 b.t. and 114+/-45 a.t. in responsive and 151+/-11 b.t. and 125+/-36 a.t. in unresponsive dogs). Similar results were observed in the evolution of experimentally infected animals after consecutive and specific treatments. Overall results show the great variation in Leishmania-specific IgG1 expression in asymptomatic and symptomatic dogs, their lack of correlation with that of IgG2 and chemotherapy is more effective in dogs with initially high expression of IgG1.

Allopurinol↗
PubMed2000

Leishmania infantum: stage-specific activity of pentavalent antimony related with the assay conditions.

The determination of the intrinsic sensitivity of Leishmania strains to pentavalent antimonials in clinical trials, before treatment is begun, is essential in order to avoid failures and to allow alternative drugs to be chosen. A comparative study of SbV activity on promastigotes, axenic amastigote-like cells, and intracellular amastigotes of Leishmania infantum, when administered in the form of meglumine antimoniate and free, in hydrochloric solution, was performed. Results indicate that the conditions under which the promastigotes were cultured affect the IC(50) obtained, although results were homogeneous when the products were assayed on axenic-like and intracellular amastigotes. The IC(50) obtained for SbV in the form of meglumine antimoniate or in hydrochloric solution on promastigotes cultured in Schneider's medium depends on the growth rate of the culture and therefore could be regulated by modifying the fetal calf serum concentration in the medium. The pH of the culture medium strongly affected the activity of meglumine antimoniate but not that of the SbV hydrochloric solution on promastigotes cultured in Schneider's medium. This influence of pH was observed to a much lesser extent when promastigotes were cultured on M199 or RPMI media. In homogeneous culture conditions, which included the regulation of the promastigote growth rate through the heat-inactivated fetal calf serum concentration in the medium and the dilution of the meglumine antimoniate with Schneider's medium at pH 6.5, the activity of SbV, free or in the form of meglumine antimoniate, was the same in promastigotes, intracellular amastigotes, and axenic amastigote-like cells.

Animals↗
PubMed1999

Epidemiology of canine leishmaniosis in Catalonia (Spain) the example of the Priorat focus.

An epidemiological survey of canine leishmaniosis was conducted in the Priorat, a rural region in the Northeast of Spain, for 10 years (1985-1994). Seroprevalence throughout the region, determined by dot-ELISA and IFI, was 10.2% (8-12%). Forty percent of the dogs studied had a low level of anti-Leishmania antibodies, whereas only 50% were seronegative. Only one-third of the seropositive dogs had evident symptoms of the disease. Annual incidence of the disease was 5.7% and the level of endemicity was stable during the study. Four Leishmania zymodemes (MON-1, MON-29, MON-77, MON-105) were present in the focus, and their distribution in the different hosts is discussed. Apart from dogs and foxes, no other reservoir host has been found in the region.

Age Factors↗
PubMed1998

Pharmacokinetics of meglumine antimoniate after administration of a multiple dose in dogs experimentally infected with Leishmania infantum.

Pharmacokinetics of meglumine antimoniate in dogs with experimentally induced leishmaniosis has been investigated. After infection, dogs received a dose of 75 mg kg-1 of meglumine antimoniate twice daily by subcutaneous injection for 10 days. Blood samples were collected throughout the treatment. No statistical differences were found in the kinetic behaviour of the drug administered as a single dose to healthy dogs and that administered as a multiple dose to infected animals. However, peak plasma concentrations (Cmax) of 30.8 +/- 12.8 micrograms ml-1 found after this dosage regimen were higher than those observed after the single dose administration of 100 mg kg-1 24 h-1. Furthermore, sustained antimony concentrations of 1.14 +/- 0.52 micrograms Sb ml-1 were detected throughout the treatment. No signs of toxicity were found in the animals treated indicating that this regimen would be very appropriate to treat canine leishmaniosis.

Analysis of Variance↗
PubMed1997

Serologic diagnosis of canine leishmaniasis by dot-ELISA.

A dot-enzyme-linked immunosorbent assay (ELISA) using protein A-peroxidase was evaluated as a diagnostic test for canine leishmaniasis. The test results were in agreement with parasitologic diagnosis and indirect immunofluorescence assay results. The sensitivity of the test calculated on 31 dogs with positive parasitologic examination was 90% when a titer of 1/800 was established as a cutoff and 100% when a titer of 1/400 was established. The specificity calculated on the canine population from nonendemic areas was 100% when both titers were established. Nevertheless, in endemic areas titers near the cutoff need careful interpretation. The results of this study demonstrate that dot-ELISA protein A using a bio-dot apparatus is highly suitable for seroepidemiologic field work.

Animals↗
PubMed1995

Serological diagnosis and treatment of canine leishmaniasis.

The changes in the titres of anti-leishmania antibodies in 25 dogs with leishmaniasis were studied by using a Dot-ELISA technique while they were being treated with N-methylglucamine and allopurinol. When the diagnosis of leishmaniasis was established, 21 of the dogs had positive titres (1:800 or higher), and after treatment, 15 of them still had high titres, in most cases the same as at the point of the diagnosis. In four dogs the titres decreased, and were less than the cut-off value in two cases nine months after treatment. Only four dogs had titres less than the cut-off value when they were diagnosed, but one month later the titres in all four dogs had reached the cut-off value. There was no correlation between the serological titres and the severity of the clinical signs. It is concluded that the Dot-ELISA is a sensitive method for the diagnosis of canine leishmaniasis but is not satisfactory for monitoring the clinical development of the disease.

Allopurinol↗
PubMed1995

Leishmania-human immunodeficiency virus coinfection in the Mediterranean basin: isoenzymatic characterization of 100 isolates of the Leishmania infantum complex.

Isoenzymatic characterization was done on 100 isolates obtained from visceral leishmaniasis (VL) patients coinfected with human immunodeficiency virus (HIV); isolates had been received between 1986 and 1993 at the International Leishmania Cryobank and Identification Centre in Montpellier, France. Electrophoresis was done with 15 isoenzymes using the starch gel technique combined, where appropriate, with isoelectrofocusing. Nine Leishmania infantum zymodemes were identified; L. infantum zymodeme MON-1, the most common parasite of human VL in the Mediterranean basin, was the most frequent in coinfections. It could also occasionally be responsible for localized cutaneous leishmaniasis lesions. Several dermotropic zymodemes, which were responsible for localized cutaneous leishmaniasis in immunocompetent patients, caused VL in HIV-positive patients. In addition, in 10 patients, a second isolate obtained during relapses occurring between 1.5 and 9.0 months after treatment was identical to the original isolate.

Animals↗