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J Alvar

Publications and source records attributed to J Alvar.

At least 37 records · Page 2Linked to original sources
PubMed1998

Post-kala-azar dermal leishmaniasis with mucosal involvement in a kidney transplant recipient: treatment with liposomal amphotericin B.

Post-kala-azar dermal leishmaniasis (PKDL) is a rare clinical variant of cutaneous leishmaniasis. It is very common in the Indian subcontinent and less frequent in East Africa, but exceptional in the American and European continents. We have observed a case of PKDL in a renal transplant recipient. No systemic symptoms were present. The patient was treated with liposomal amphotericin B. We emphasize the unusual aspects of this case: the appearance of PKDL in Europe, its relationship with immunosuppression, the severe mucosal involvement and the excellent response to liposomal amphotericin B, a newly described treatment for the disease.

Adult↗
PubMed1998

Dynamics of serum cytokines in patients with visceral leishmaniasis and HIV-1 co-infection.

Serum cytokine levels and peripheral T cell subpopulations of HIV-1-infected patients before, during and after active visceral leishmaniasis (VL) were analysed and compared with appropriate controls. At VL diagnosis, co-infected patients showed higher serum levels of interferon-gamma (IFN-gamma) than matched HIV-1 controls without VL, and lower serum concentrations of IL-10 than non-immunocompromised VL controls. High levels of tumour necrosis factor-alpha (TNF-alpha) and IFN-gamma were present in the sera of HIV-1-infected patients with active VL. TNF-alpha remained elevated after VL recovery. A steady decline in the CD4+ cell count, an increase of serum HIV viraemia and a progressive seroconversion for the HIV-1 p24 antigen was observed during the course of VL disease. Thus, an aberrant activation of the TNF system with possible negative immunological and virological consequences is present in HIV-1-infected patients with VL. A more extensive prospective validation of these findings in a bigger cohort of patients will nevertheless be necessary. The results support the hypothesis that different opportunistic infection agents may trigger the production of proinflammatory cytokines during immunodeficiency, and in this way accelerate the course of HIV-1 disease.

AIDS-Related Opportunistic Infections↗
PubMed1998

Clinicoepidemiologic characteristics, prognostic factors, and survival analysis of patients coinfected with human immunodeficiency virus and Leishmania in an area of Madrid, Spain.

From 1987 to 1995, a retrospective case study was conducted at the Ramon y Cajal Hospital in Madrid, Spain, a public teaching hospital with 1,100 beds, to determine the clinicoepidemiologic characteristics, survival, and prognostic factors of patients with visceral leishmaniasis (VL) and human immunodeficiency virus (HIV) infection. The prevalence of VL in HIV+ patients compared with HIV- patients was studied. Epidemiologic, clinical, and parasitologic characteristics, as well as the effects of treatment, prognosis, and survival in 54 HIV+ patients (90 episodes) with VL were defined. Comparative survival studies among patients with and without acquired immunodeficiency syndrome (AIDS)-defining criteria and multivariate analysis of survival risk factors were performed. The prevalence of VL in patients with AIDS was much higher than in immunocompetent individuals. In spite of a good initial response to treatment for VL, 60.6% of the patients had relapsed by the end of one year. Mortality from the first episode was 18.5%, and 24% died in the first month after diagnosis of any VL episode. The mean survival of the 29 patients who died was 10.27 months. Survival in patients with and without AIDS at the time of the first episode of VL was compared at 30 months: 53.7% versus 20.5% (P = 0.00149). We found no significant difference (P = 0.24) in the survival of HIV+ patients who had died of VL without AIDS at the time of the first episode of VL compared with those of a control group of 413 dead patients with AIDS without VL. A diagnosis of AIDS at the time of the first episode of VL and thrombocytopenia were the only risk factors found related to survival. We conclude that in AIDS patients, VL is a recurrent disease that is highly prevalent and whose clinical course is modified by HIV.

Acquired Immunodeficiency Syndrome↗
PubMed1998

The role of serology in the diagnosis and prognosis of visceral leishmaniasis in patients coinfected with human immunodeficiency virus type-1.

To define the possible role of serology in the diagnosis and prognosis of visceral leishmaniasis (VL) in patients with human immunodeficiency virus type-1 (HIV-1) infection, the dynamics of humoral immune responses was investigated in 20 coinfected patients. Sequential sera obtained before, during, and after VL diagnosis were analyzed by an indirect immunofluorescent antibody test (IFAT), a recombinant ELISA (using the rK39 protein), and immunoblotting. During the active course of the disease, positive results were found by IFAT or ELISA in 22% of the cases and by immunoblotting in 78% of the cases. A great variability in the response was observed during the follow-up with a trend to more positive results near the time of VL diagnosis. Forty-six percent of the patients were positive by IFAT or ELISA on at least one time point before VL and 37.5% were positive during the period following treatment. These results confirm the limited usefulness of the IFAT and ELISA in the diagnosis of VL in coinfected patients and demonstrate their low ability to predict the development or the outcome of disease. In these patients, immunoblotting could be a useful tool for studying the natural course of leishmaniasis, although it has limited value for diagnosis or treatment control.

Acute Disease↗
PubMed1997

Visceral leishmaniasis in patients infected with the human immunodeficiency virus.

The experience with 52 episodes of visceral leishmaniasis diagnosed in 43 patients is reported. The most common symptoms were fever (81%), splenomegaly (65%), hepatomegaly (63%), and pancytopenia (73%). In 79% of the patients, CD4+ cell counts were < 100 cells/mm3. Prior or simultaneous diagnosis of AIDS was made in 29 (67%) patients. Diagnosis was considered fortuitous in 19% of the episodes. In 27% of the episodes, the diagnosis was made on the basis of demonstration of parasites outside the reticuloendothelial system, chiefly blood (7 cases) and gastrointestinal mucosa (5 cases). Parasites were frequently observed or cultured from blood (22/37 episodes) or the digestive tract (8/9 episodes). High antimony doses were more effective than low doses in achieving clinical or parasitological cure (rate of cure, 80% vs. 40%, p = 0.11). Severe toxicity was observed in six (11.7%) of the 51 treated episodes. Severe AIDS-related diseases [odds ratio (OR) 10, p < 0.05] and CD4+ counts (OR 12, p < 0.05) were independent factors for early death. Prophylaxis with monthly pentamidine was not useful in reducing relapses of visceral leishmaniasis.

AIDS-Related Opportunistic Infections↗
PubMed1997

Leishmania infantum is clonal in AIDS patients too: epidemiological implications.

OBJECTIVE: To test, in AIDS patients, a previously proposed hypothesis of clonal population structure in Leishmania infantum, the agent of visceral leishmaniasis. DESIGN: Forty-three stocks of L. infantum isolated from AIDS patients in Spain were analysed by multilocus enzyme electrophoresis. METHODS: The results were analysed in terms of population genetics according to previously described statistical methods. Departures from panmixia were examined by linkage disequilibrium analysis. RESULTS: As previously shown in HIV-negative patients, classical manifestations of clonality were shown, namely strong linkage disequilibrium, over-representation of genotypes and overall lack of genotype diversity. The same dominant clonal genotype (MON1) was recorded in both HIV-positive and HIV-negative patients. Frequency of this dominant genotype was not statistically different in HIV-positive and HIV-negative patients. CONCLUSIONS: The parasite population under survey appears to be clonal; parasite genotypes can therefore be equated to natural clones, stable in space and time, which can be used as multilocus epidemiological markers. Nevertheless, additional studies are required to better estimate the long-term stability of these clonal genotypes and the possible interference of gene exchange at an evolutionary scale.

AIDS-Related Opportunistic Infections↗
PubMed1997

Leishmania and human immunodeficiency virus coinfection: the first 10 years.

Over 850 Leishmania-human immunodeficiency virus (HIV) coinfection cases have been recorded, the majority in Europe, where 7 to 17% of HIV-positive individuals with fever have amastigotes, suggesting that Leishmania-infected individuals without symptoms will express symptoms of leishmaniasis if they become immunosuppressed. However, there are indirect reasons and statistical data demonstrating that intravenous drug addiction plays a specific role in Leishmania infantum transmission: an anthroponotic cycle complementary to the zoonotic one has been suggested. Due to anergy in patients with coinfection, L. infantum dermotropic zymodemes are isolated from patient viscera and a higher L. infantum phenotypic variability is seen. Moreover, insect trypanosomatids that are currently considered nonpathogenic have been isolated from coinfected patients. HIV infection and Leishmania infection each induce important analogous immunological changes whose effects are multiplied if they occur concomitantly, such as a Th1-to-Th2 response switch; however, the consequences of the viral infection predominate. In fact, a large proportion of coinfected patients have no detectable anti-Leishmania antibodies. The microorganisms share target cells, and it has been demonstrated in vitro how L. infantum induces the expression of latent HIV-1. Bone marrow culture is the most useful diagnostic technique, but it is invasive. Blood smears and culture are good alternatives. PCR, xenodiagnosis, and circulating-antigen detection are available only in specialized laboratories. The relationship with low levels of CD4+ cells conditions the clinical presentation and evolution of disease. Most patients have visceral leishmaniasis, but asymptomatic, cutaneous, mucocutaneous, diffuse cutaneous, and post-kala-azar dermal leishmaniasis can be produced by L. infantum. The digestive and respiratory tracts are frequently parasitized. The course of coinfection is marked by a high relapse rate. There is a lack of randomized prospective treatment trials; therefore, coinfected patients are treated by conventional regimens. Prophylactic therapy is suggested to be helpful in preventing relapses.

Animals↗
PubMed1996

Leishmaniasis presenting as a dermatomyositis-like eruption in AIDS.

Three patients are described with leishmaniasis and AIDS, with cutaneous lesions mimicking dermatomyositis. Leishmania organisms were observed in great numbers in the dermis of lesional skin biopsy specimens. They were also present inside keratinocytes in all layers of the epidermis in one patient. Skin cultures from all patients and bone marrow culture in patients 1 and 3 revealed Leishmania infantum. Leishmania organisms were also found in nonlesional skin. The absence of proximal symmetric muscle weakness, elevated muscle enzymes, myopathic electromyograms, or characteristic histopathologic and immunologic features of dermatomyositis, and the rapid and complete clearance or marked improvement of the cutaneous lesions after treatment for leishmaniasis, make us consider true dermatomyositis unlikely. We suggest that leishmaniasis be included in the list of diseases capable of inducing a dermatomyositis-like eruption.

AIDS-Related Opportunistic Infections↗
PubMed1996

Urine sample used for congenital toxoplasmosis diagnosis by PCR.

The diagnosis of toxoplasmosis in congenitally infected infants can be difficult; serology is unreliable, and diagnosis must be based on the combination of symptomatology and direct demonstration of the parasite. Four infants suspected of having Toxoplasma gondii infection were studied by serological analysis, tissue culture, and PCR determination. T. gondii was isolated from the urine of one patient. The parasite was detected by PCR in the blood and cerebrospinal fluid of three infants and in the urine in all patients. Because nested PCR proved to be a sensitive, relatively rapid, and specific method and because it can be applied to a variety of different clinical samples, PCR can be a valuable technique for the identification of T. gondii infections in children. The present study indicates that PCR examination of urine, a fluid never before used for diagnosis in this age group, may be valuable in diagnosing cases of congenital toxoplasmosis.

Animals↗
PubMed1995

Epidemiology of canine leishmaniasis in the Madrid region, Spain.

A cross-sectional serological survey was carried out in the Madrid Autonomous Region (Comunidad de Madrid) in order to study and describe canine leishmaniasis epidemiology. The presence of leishmaniasis-specific antibodies was ascertained by immunofluorescence testing, 591 dogs were screened, revealing a prevalence of 5.25% (95% confidence interval 7.4-3.6), with no difference being encountered between rural and periurban areas. Age-specific prevalence exhibits a peak at 2-3 years and another at 7-8 years. Incidence or force of infection by occupation is as follows: pet dogs 0.059 (95% confidence interval 0.009-0.108) and working dogs 0.035 (95% confidence interval 0.012-0.057), there being a ratio between infection rates of 1.7, viz., indicating a 70% greater risk of infection among pet than among working dogs. The basic case reproduction number R0 is 1.06, suggesting that very intense control measures would not be needed for a drop in prevalence and incidence of infection to be achieved.

Age Factors↗
PubMed1995

Parasitic culture of buffy coat for diagnosis of visceral leishmaniasis in human immunodeficiency virus-infected patients.

Two samples of buffy coat from the peripheral blood of 25 human immunodeficiency virus-positive patients with proven visceral leishmaniasis, as determined with a bone marrow aspirate (stain and culture), were cultured onto Schneider's and Novy-McNeal-Nicolle media. Hemoculture positivity was 67%. The average growing time was 10 days. This is an easy, noninvasive, and sensitive technique.

AIDS-Related Opportunistic Infections↗
PubMed1995

In vitro susceptibility of Plasmodium falciparum to chloroquine, amodiaquine, quinine, mefloquine, and sulfadoxine/pyrimethamine in Equatorial Guinea.

Between March 1990 and June 1992, a study was carried out in Equatorial Guinea on the in vitro response of Plasmodium falciparum to different antimalarial drugs. Field work for the study was conducted both in the country's island region as well as on the mainland, and resistant isolates were found to exhibit interregional differences. On the island of Bioko, 204 tests were performed with 16% (11 of 69) resistant to chloroquine, 9% (4 of 46) resistant to quinine, 14% (6 of 43) resistant to a combination of sulfadoxine/pyrimethamine, and 6.5% (3 of 46) resistant to amodiaquine. In the mainland area of Bata, the same antimalarial drugs and mefloquine were tested with the following results: 9% (5 of 58) resistant to chloroquine; 2% (1 of 58) resistant to amodiaquine, and 3% (2 of 58) resistant to a combination of sulfadoxine/pyrimethamine. No isolates resistant to quinine or mefloquine were found. Effective concentrations (EC50, EC90, and EC99) and regression lines (log dose/response) for each antimalarial drug were calculated to establish a surveillance system for antimalarial drug chemosensitivity in Equatorial Guinea. Finally, 12 isolates from 12 patients previously treated with chloroquine were studied to compare both tests (in vivo-in vitro) and obtain a correlation between the RII and RIII types of in vivo and in vitro resistances. No correlation for the RI type was found between the two methods.

Amodiaquine↗
PubMed1994

Assessment of allopurinol plus meglumine antimoniate in the treatment of visceral leishmaniasis in patients infected with HIV.

We report on 11 patients with HIV infection and visceral leishmaniasis and who were treated with meglumine antimoniate plus allopurinol for 3 weeks (six patients) or 4 weeks (five patients). Clinical and parasitological cures were achieved in four of the five patients treated for 4 weeks and in one of the six patients treated for 3 weeks. Only one patient developed a severe maculopapular rash. Allopurinol plus meglumine antimoniate was found to be a safe combination of drugs for the treatment of visceral leishmaniasis in patients infected with HIV. The optimal length of this treatment is unknown but a course of at least 4 weeks' duration would appear to be necessary for obtaining parasitological cure in most cases.

AIDS-Related Opportunistic Infections↗
PubMed1994

Canine leishmaniasis: clinical, parasitological and entomological follow-up after chemotherapy.

Six naturally infected dogs [two with no signs of leishmaniasis ('asymptomatic'), two with a few signs ('oligosymptomatic') and two with many signs ('polysymptomatic')] were studied before and after chemotherapy. Another two, non-infected dogs were kept as controls. The dogs were studied clinically, haematologically and parasitologically five times over 11 months and their infectivity to sandflies was evaluated before and after the treatment. The 'asymptomatic' dogs were as infective to sandflies as the 'symptomatic' before treatment but all dogs were un-infective for at least a few months following chemotherapy. Treatment led to a temporary improvement in the clinical and biochemical condition of most of the dogs, the symptomatic dogs becoming asymptomatic, but parasitological cure was uncommon after 10 months' follow-up. There was often no correlation between clinical condition, parasitological condition and infectivity to sandflies. Some dogs from both the 'asymptomatic' and 'symptomatic' groups became infective to sandflies several months post-treatment.

Animals↗