Visceral leishmaniasis in patients infected with human immunodeficiency virus (HIV)

Visceral Leishmaniasis of Atypical Location in Immunodepressed Patients: A Report of Two Cases

Two cases of atypical location of visceral leishmaniasis in two immunodepressed patients are described. In one case, leishmaniasis was seen involving the mucosa of both the esophagus and duodenum in an acquired immunodeficiency syndrome patient whose initial symptoms were odynophagia and esophagospasm, resulting from an esophageal ulcer. In the second case, leishmaniasis was seen in the mucosa of the colon of a human immunodeficiency virus-seronegative patient suffering from long-standing untreated pulmonary tuberculosis; the initial symptoms were fecal incontinence and diarrhea. Both patients lived in an area where leishmaniasis is endemic. As the condition of both patients improved after treatment with meglumine antimoniate, it is assumed that their symptoms were caused by leishmania organisms. Pathologists working in nonendemic areas should be aware of this protozoon when interpreting alimentary tract biopsies of immunodepressed patients, both human immunodeficiency virus-seropositive and human immunodeficiency virus-seronegative, who have visited areas where leishmaniasis is endemic.

Successful therapeutic splenectomy in an HIV patient with relapsing visceral leishmaniasis

A 43-year-old HIV-positive Ethiopian immigrant presented with persistent diarrhoea, hepatosplenomegaly and pancytopaenia. Visceral leishmaniasis was diagnosed by multiple gastrointestinal tract biopsies. Blood polymerase chain reaction (PCR) was positive for Leishmania donovani. Despite highly active antiretroviral therapy (HAART) and multiple courses of antileishmanial treatments, including liposomal amphotericin and sodium stibogluconate, the patient had multiple relapses. CD4 counts remained at 40-60 cells/µL although viral loads were undetectable. Splenectomy resulted in resolution of the patient's pancytopaenia and in rising CD4 levels, which enabled a long-lasting remission.

The diagnostic accuracy of serologic and molecular methods for detecting visceral leishmaniasis in HIV infected patients: meta-analysis

Background

Human visceral leishmaniasis (VL), a potentially fatal disease, has emerged as an important opportunistic condition in HIV infected patients. In immunocompromised patients, serological investigation is considered not an accurate diagnostic method for VL diagnosis and molecular techniques seem especially promising.

Objective

This work is a comprehensive systematic review and meta-analysis to evaluate the accuracy of serologic and molecular tests for VL diagnosis specifically in HIV-infected patients.

Methods

Two independent reviewers searched PubMed and LILACS databases. The quality of studies was assessed by QUADAS score. Sensitivity and specificity were pooled separately and compared with overall accuracy measures: diagnostic odds ratio (DOR) and symmetric summary receiver operating characteristic (sROC).

Results

Thirty three studies recruiting 1,489 patients were included. The following tests were evaluated: Immunofluorescence Antibody Test (IFAT), Enzyme linked immunosorbent assay (ELISA), immunoblotting (Blot), direct agglutination test (DAT) and polimerase chain reaction (PCR) in whole blood and bone marrow. Most studies were carried out in Europe. Serological tests varied widely in performance, but with overall limited sensitivity. IFAT had poor sensitivity ranging from 11% to 82%. DOR (95% confidence interval) was higher for DAT 36.01 (9.95–130.29) and Blot 27.51 (9.27–81.66) than for IFAT 7.43 (3.08–1791) and ELISA 3.06 (0.71–13.10). PCR in whole blood had the highest DOR: 400.35 (58.47–2741.42). The accuracy of PCR based on Q-point was 0.95; 95%CI 0.92–0.97, which means good overall performance.

Conclusion

Based mainly on evidence gained by infection with Leishmania infantum chagasi, serological tests should not be used to rule out a diagnosis of VL among the HIV-infected, but a positive test at even low titers has diagnostic value when combined with the clinical case definition. Considering the available evidence, tests based on DNA detection are highly sensitive and may contribute to a diagnostic workup.

Human visceral leishmaniasis (VL), a potentially fatal disease, has emerged as an important opportunistic condition in HIV infected patients. In immunocompromised patients, serological investigation is considered not an accurate diagnostic method for VL diagnosis and molecular techniques seem especially promising. Demonstration of Leishmania parasites in bone marrow aspirate or in other biologic specimen, either by visualization or culture, remains the most reliable diagnostic technique in the setting of HIV co-infection. However, these tests are difficult to perform in rural areas and some of them are invasive and carry a risk of complication. This work is a systematic review to evaluate the accuracy of serologic and molecular tests for VL diagnosis in HIV-infected patients. Two reviewers searched the literature, evaluating quality of studies and comparing performance of diagnostic tests. Thirty three studies were included. Most studies were carried out in Europe. Serological tests varied in performance, but with overall limited sensitivity. Based on the evidence, serological tests should not be used to rule out a diagnosis of VL among HIV-patients, but a positive test at even low titers has diagnostic value when combined with the clinical case definition. Tests based on DNA detection are highly sensitive and may contribute to a diagnostic workup.

The development of effector T cell subsets in murine Leishmania major infection

Leishmania major infection has proven an exceptional model for CD4+ subset development in inbred mice. Most strains contain infection coincident with the appearance of T helper 1 (Th1) cells that produce gamma-interferon (IFN-gamma) required for macrophage activation. In contrast, mice on the BALB background are unable to control infection due to the development of Th2 cells that produce counter-regulatory cytokines, particularly interleukin 4 (IL-4), capable of abrogating the effects of IFN-gamma. Selective gene disruption studies in mice have illustrated critical components of the host response to L. major. Mice deficient in beta 2 microglobulin, which have no major histocompatibility complex (MHC) class I or CD8+ T cells, control infection as well as wild-type mice, whereas mice deficient in MHC class II (and CD4+ T cells) suffer fatal infection. Mice with disruption of the gene coding IFN-gamma are also incapable of containing infection, reflecting absolute requirements for this cytokine. A number of interventions have been demonstrated to abrogate Th2 cell development in BALB mice, enabling these mice to control infection. Each of these--IL-12, anti-IL-4, anti-IL-2, anti-CD4 and CTLA4-Ig--has in common the capacity to make IL-4 rate limiting at the time of CD4+ cell priming.

Laryngeal Leishmaniasis in Malta

The localization of Leishmania spp. in the larynx is rare especially when not associated with immunosuppression or with visceral or cutaneous leishmaniasis. We present a case of isolated laryngeal leishmaniasis, the first of its kind documented in Malta and infrequently reported from the Mediterranean basin.

Comparative protein modeling and surface analysis of Leishmania sirtuin: A potential target for antileishmanial drug discovery

Homology model of Leishmania SIR2 shed new light on the ligand binding features of this enzyme. The molecular electrostatic potentials (MESP), the cavity depth analysis, and LmSIR2-hSIRT2 models' superposition suggested that the nicotinamide binding catalytic domain has several minor but potentially important structural differences. These differences could be exploited for designing antileishmanial compounds.

Leishmaniasis and AIDS co-infection: the Spanish example

There are an estimated 300 instances of Leishmania/HIV co-infection, of which 200 have occurred in Spain. Jorge Alvar here asks: is there an epidemiological or immunological basis for this high proportion?

Visceral leishmaniasis in immunocompromised patients with and without AIDS: a comparison of clinical features and prognosis

Visceral leishmaniasis is basically a disease of healthy infants and adults. However, in the last decade an increasing number of cases of kala azar in immunocompromised patients have been reported with emphasis on atypical manifestations of the disease. During a period of 11 years, 20 immunocompromised patients with AIDS (12 patient), haematological neoplasia (3 patients), corticosteroid therapy (3 patients) or renal transplantation (2 patients) were studied by one or more of the authors. We did not find differences in the presentation of leishmaniasis between patient with or without AIDS and most patients had fever, enlargement of the liver and spleen, blood cytopenias and biochemical abnormalities. Serology was more frequently positive in HIV-negative than in HIV-positive patients (100% versus 63.6%; P=0.13). Bone marrow biopsy was diagnostic in 66% and 87% of patients with and without AIDS, respectively. Failure of anti-leishmanial therapy occurred in 6 of 19 patients treated (31.5%), and 3 patients with AIDS and another 3 without AIDS died during the first episode of leishmaniasis. Of 12 survivors, relapses occurred in five (41.6%). Only patients in whom immunosuppression was ameliorated by means of antiretroviral therapy or by reduction of corticosteroid and other immunosuppressive drugs did not relapse. Treatment of kala azar in immunocompromised host is in satisfactory and new drugs or strategies are urgently needed.

Granulomatous lung diseases in the tropics

International travel, changing immigration patterns, and political upheavals have transformed the epidemiological picture of many tropical granulomatous disorders [53]. These diseases are seen with an increasing frequency in the United States, Europe, and other developed countries. Physicians must now become familiar with illnesses that were previously regarded as being "exotic" because of this increasing prevalence. Accurate diagnosis is important because therapy is significantly different for infectious granulomatous disorders than for non-infectious diseases.

Antileishmanial activities of aphidicolin and its semisynthetic derivatives

Aphidicolin and a series of semisynthetic aphidicolan derivatives have been identified in in vitro tests as novel drugs with antiparasitic potential. All compounds have been tested against extracellular promastigotes of Leishmania donovani, L. infantum, L. enriettii, and L. major and against intracellular amastigotes of L. donovani in murine macrophages. The compounds showed antileishmanial activity at concentrations in the microgram range (50% effective concentration [EC(50)] = 0.02 to 1.83 microg/ml). The most active derivative (aphidicolin-17-glycinate hydrochloride) had EC(50)s of 0. 2 microg/ml against extracellular and 0.02 microg/ml against intracellular L. donovani parasites. To validate the pharmacological potential of tested drugs, pharmacological safety was determined by testing all compounds against two neoplastic cell lines (squamous carcinoma [KB] and melanoma [SK-Mel]) and against murine bone marrow-derived macrophages as host cells. With minor exceptions only for macrophages, tested aphidicolans did not show significant cytotoxicity (EC(50) > 25.0 microg/ml). Structure-activity relationships of these aphidicolan derivatives are discussed.

Visceral leishmaniasis in human immunodeficiency virus (HIV)-infected and non-HIV-infected patients. A comparative study

Visceral leishmaniasis is an endemic infection in Mediterranean countries, where it has become a frequent complication of acquired immunodeficiency syndrome (AIDS). The incidence of visceral leishmaniasis is increasing in Spain due to human immunodeficiency virus (HIV)-related cases, but some aspects of its epidemiology, clinical features, and management remain unknown. In addition, no comparative clinical studies about the disease in HIV-infected and non-HIV-infected patients have been reported. During a 24-year period, 120 cases of visceral leishmaniasis were diagnosed at our institution and 80 (66%) were associated with HIV infection. The mean age at diagnosis was higher in HIV-infected that in non-HIV-infected patients (33.2 versus 23.2 yr; p = 0.002), but the male/female ratio was similar in both groups. The main risk factor for HIV infection was intravenous drug abuse (78.7%). The clinical presentation of leishmaniasis was similar in both groups, but HIV-infected patients had a lower frequency of splenomegaly than HIV-negative individuals (80.8% versus 97.4%; p = 0.02). HIV-infected patients had a greater frequency and degree of leukopenia, lymphocytopenia, and thrombocytopenia. Most of them were profoundly immunosuppressed (mean CD4+ lymphocyte count, 90 cells/mm3) at the time of diagnosis of leishmaniasis, and 53.7% had AIDS. The sensitivity of serologic studies for Leishmania was significantly lower in HIV-infected than in non-HIV-infected patients (50% versus 80%; p < 0.001), but the diagnostic yield of bone marrow aspirate (67.1% versus 79.4%) and bone marrow culture (62.9% versus 66.6%) was similar in both groups. After initial treatment, the response rate was significantly lower in HIV-infected than in non-HIV-infected individuals (54.8% versus 89.7%; p = 0.001). The relapse rate was 46.2% and 7.5%, respectively (p < 0.001). Secondary prophylaxis with antimonial compounds or amphotericin B seems to be useful in preventing relapses in HIV-infected patients. The mortality rate was higher (53.7% versus 7.5%; p < 0.001) and the median survival time shorter (25 versus > 160 mo; p < 0.001) in AIDS patients than in HIV-negative individuals. Although leishmaniasis could contribute to death in a significant number of HIV-infected patients, it was the main cause of death in only a few of them. The CD4+ lymphocyte count and the use of highly active antiretroviral therapy and secondary prophylaxis for leishmaniasis were the most significant prognostic factors for survival in AIDS patients. Visceral leishmaniasis behaves as an opportunistic infection in HIV-infected individuals and should be considered as an AIDS-defining disease.

Therapy of visceral leishmaniasis in renal transplant recipients intolerant to pentavalent antimonials

Visceral leishmaniasis should be suspected in renal transplant recipients in whom a fever develops of unknown origin. A 53-year-old renal transplant recipient developed pyrexia, hepatosplenomegaly, and pancytopenia 4 years after transplantation. Antileishmaniasis serology was negative, and the diagnosis was confirmed through bone marrow examination. Treatment with glucantine (N-methylglucamine antimoniate) led to acute pancreatitis, and treatment with ketoconazole plus allopurinol for 21 days was effective to eradicate Leishmania donovani.

The histological spectrum of visceral leishmaniasis caused by Leishmania infantum MON-1 in acquired immune deficiency syndrome

Visceral leishmaniasis (VL) due to Leishmania infantum is endemic in Southern France and can be considered as an opportunistic infection in patients with acquired immunodeficiency syndrome (AIDS). Co-infection with Leishmania sp. and human immunodeficiency virus (HIV) is emerging, but pathological findings of leishmaniasis in AIDS have been poorly documented, and scattered case reports have include morphological descriptions. The clinicopathologic analysis of 16 patients with HIV and VL were evaluated. The clinical presentation was characteristic of VL, with fever, hepatosplenomegaly, and pancytopenia in 6 patients, and the diagnosis was confirmed by finding amastigotes of Leishmania sp. in bone marrow smears and biopsy specimens. In 4 patients, the initial diagnosis of VL was made fortuitously in gastrointestinal biopsies performed systematically (3 patients) or in case of diarrhea (1 patient). In one duodenal biopsy, Leishmania sp. and Mycobacteria sp. were associated. Liver biopsy allowed the diagnosis of VL in 3 cases. Autopsy was performed in 9 patients, showing a disseminated leishmaniasis with very unusual localizations (adrenal and heart) in 2 cases. Cutaneous leishmaniasis involvement was noted before (4 patients), at the same time (2 patient), or after (1 patient) the diagnosis of VL. Inflammatory infiltrates noted with Leishmania sp. infection were made by CD68 macrophages with (8 patients) or without (8 patients) associated CD8 positive lymphocytes. Immunoperoxidase study using polyclonal anti-Leishmania sp. antibodies contributed to the diagnosis in all cases. Electron microscopy of 2 digestive biopsy specimens showed the ultrastructural characteristics of Leishmania sp. amastigotes. The zymodeme MON-1 of L infantum was identified by isoenzyme electrophoresis in all patients. The mean of CD4 counts was 37/mm3 at the time of diagnosis, and the mean duration before the death was 8 months. As shown in this study, VL in AIDS can be diagnosed in gastrointestinal or liver biopsies. Diagnosis of VL was made when the CD4 count was very low and was correlated with a poor prognosis.

Dermatofibroma parasitized by Leishmania in HIV infection: a new morphologic expression of dermal Kala Azar in an immunodepressed patient

Visceral leishmaniasis is a protozoan infection that may complicate the course of patients with human immunodeficiency virus (HIV). Dermatofibroma is a cutaneous fibrohistiocytic lesion considered neoplastic by some authors and inflammatory by others. Eruptive dermatofibromas have been described in patients with HIV infection or with other altered immunity situations. We present the case of a 32-year-old, HIV-positive man with visceral leishmaniasis who complained of the appearance of a cutaneous lesion in the leg formed by the coexistence of dermatofibroma and Leishmania parasitic colonization. As far as we know, this type of association has not been reported previously. We consider that the dermatofibroma could have developed as an unusual form of fibrohistiocytic reaction to leishmania. From a practical approach, we recommend the search of leishmaniasis in dermatofibroma in immunosuppressed patients.

Acute pancreatitis in human immunodeficiency virus-infected patients: a review

Acute pancreatitis is a clinical condition that develops when active pancreatic inflammation is induced by stimuli noxious to the pancreas. Patients infected with human immunodeficiency virus (HIV) often have histologic abnormalities of the pancreas, and acute pancreatitis is much more common in HIV-infected patients than in the general population. This article reviews the epidemiology and etiology of acute pancreatitis in HIV-infected patients. The clinical presentation and treatment of acute pancreatitis in HIV-infected patients are also reviewed.

Diagnostic usefulness of percutaneous liver biopsy in HIV-infected patients with fever of unknown origin

OBJECTIVES

to determine the value of percutaneous liver biopsy (PLB) in the diagnosis of fever of unknown origin (FUO) in HIV-infected patients and establish a prediction model for its usefulness to enable diagnosis of FUO in these patients to be standardized.

METHODS

a total of 58 HIV-infected patients who underwent PLB for the evaluation of FUO were studied at 'Carlos Haya' Hospital in Malaga, Spain. The patients were classified into three groups, according to the results of the PLB: (a) diagnostic PLB (when a definitive diagnosis was obtained); (b) helpful PLB (the tissue sample showed suggestive, but not definitive, findings); and (c) normal or non-specific PLB (no contribution to diagnosis, the findings being normal or irrelevant). Multivariate analysis was made to establish a prediction model for the diagnostic usefulness of PLB, calculating the positive (PPV) and negative (NPV) predictive values.

RESULTS

PLB was carried out in 58 HIV-infected patients during diagnosis of FUO. Risk factors for HIV infection included intravenous drug use (72.4%), homosexual or bisexual activities (12.1%), and heterosexual transmission (15.5%). Fifty-two out of 58 patients (89.6%) had previous AIDS-defining illnesses. The mean CD4 lymphocyte count +/-SD was 56.4+/-80.9/mm3. The mean duration of fever was 43 days. Diagnosis could be established in 51 (87.9%) patients, with tuberculosis (50%) and leishmaniasis (20.7%) being the most common. The PLB was diagnostic in 25 cases (43.1%), helpful in 13 (22.4%), and normal or non-specific in the remaining 20 (34.5%). Biopsy-associated complications occurred in two cases. The presence of hepatomegaly or splenomegaly were the most useful factors in predicting the usefulness of the PLB, with a PPV of 86.1% and NPV of 68.2%. In patients with tuberculosis, an increased alkaline phosphatase and hepatomegaly had a PPV of 86.4% and a NPV of 71.4%.

CONCLUSIONS

PLB is a useful technique for the diagnosis of FUO in HIV-infected persons. Early PLB should be considered in those patients with hepatosplenomegaly and increased alkaline phosphatase levels.

Sodium stibogluconate (pentostan) overdose in a patient with acquired immunodeficiency syndrome

A 32-year-old man with acquired immunodeficiency syndrome (AIDS) admitted to the hospital for treatment of visceral leishmaniasis was inadvertently given 10 times the prescribed first dose of sodium stibogluconate ([Sb] 6.5 g instead of 0.65 g). He experienced no immediate major toxicity during the first 48 hours, but a significant rise of pancreatic enzyme activities was observed (amylase at 10 times the upper limit of normal, lipase at 50 times the upper limit of normal) without clinical signs or indications on computed tomography (CT) of pancreatitis. The third day after the overdose, he developed appendicitis, which appeared coincidental; he recovered uneventfully from surgery. Most of the overdose of Sb was eliminated within the first few hours. Pharmacokinetics remained linear; the rapid, long elimination half-lives (2.7 hours and 54 hours, respectively) were similar to those in previously published results. The administration of a chelating agent, dimercaptosuccinic acid (DMSA), 72 hours after the Sb overdose did not modify the pharmacokinetics of the medication.

Prevalence of and factors associated with visceral leishmaniasis in human immunodeficiency virus type 1-infected patients in southern Spain

The actual prevalence of visceral leishmaniasis among human immunodeficiency type 1 (HIV-1)-infected patients in the Mediterranean basin remains unknown. There is also controversy about the risk factors for Leishmania infantum and HIV-1 coinfection. To appraise the prevalence of visceral leishmaniasis in patients infected with HIV-1 in southern Spain and to identify factors associated with this disease, 291 HIV-1 carriers underwent a bone marrow aspiration, regardless of their symptoms. Giemsa-stained samples were searched for Leishmania amastigotes. Thirty-two (11%) patients showed visceral leishmaniasis. Thirteen (41%) patients had subclinical cases of infection. Centers for Disease Control and Prevention (CDC) clinical category C was the factor most strongly associated with this disease (adjusted odds ratio [OR], 1.88 [95% confidence interval, 1.22 to 2.88]), but patients with subclinical cases of infection were found in all CDC categories. Female sex was negatively associated with visceral leishmaniasis (adjusted OR, 0.42 [95% confidence interval, 0.18 to 0.97]). Intravenous drug users showed a higher prevalence than the remaining patients (13.3 versus 4.9%; P = 0.04), but such an association was not independent. These results show that visceral leishmaniasis is a very prevalent disease among HIV-1-infected patients in southern Spain, with a high proportion of cases being subclinical. Like other opportunistic infections, subclinical visceral leishmaniasis can be found at any stage of HIV-1 infection, but symptomatic cases of infection appear mainly when a deep immunosuppression is present. There is also an association of this disease with male sex and intravenous drug use.

Visceral leishmaniasis with cutaneous lesions in a patient infected with human immunodeficiency virus

We report a case of visceral leishmaniasis (VL) with cutaneous lesions in a patient infected with human immunodeficiency virus (HIV). The cutaneous lesions consisted of erythematous papules on the legs. Biopsy of one lesion showed abundant Leishmania amastigotes within epithelial cells of an eccrine sweat gland in the dermis. Leishmania organisms were also found in a blood smear. Rapid and complete clearance of the cutaneous lesions was achieved after antimony therapy. Cutaneous lesions in VL are being reported increasingly frequently in patients with HIV infection and their significance remains in discussion.

Visceral leishmaniasis (Kala-Azar) in transplant recipients: case report and review

BACKGROUND

In endemic areas, visceral leishmaniasis has been identified as an opportunistic infection in patients with derangements in their cellular immune system.

METHODS

We report a renal transplant patient with visceral leishmaniasis. We also reviewed the previously published cases of 17 organ transplant recipients with this parasitic disease.

RESULTS

Visceral leishmaniasis occurred a median time of 8 months after transplantation, and the clinical picture was characterized by fever, splenomegaly, and blood cytopenias. Leishmaniae were detected in bone marrow in 16 of 18 patients and diagnostic serology results were found in 8 of 10 tested patients. Pentavalent antimonials were used to treat 16 patients, five of which developed pancreatitis. Five of 18 patients died, including two untreated patients. Relapses of visceral leishmaniasis occurred in 4 of 13 survivors.

CONCLUSIONS

In endemic areas, visceral leishmaniasis may complicate the clinical course of organ transplantation and can have fatal consequences, particularly when untreated.

Fever of unknown origin in the HIV-infected patient: new scenario for an old problem

Many conditions may present as fever of unknown origin in the HIV-infected patient, and their relative frequency is influenced by multiple factors. The history and physical examination may provide some useful clues for the diagnosis. Haematological, biochemical, and conventional radiological tests are rarely diagnostic; even serological and/or microbiological tests have some limitations in these patients. The geographical setting and the local prevalence of diseases are of the utmost importance. Infections that have a world-wide distribution, such as tuberculosis, should be intensively searched for, particularly in areas of high prevalence. The measurement of the CD4+ cell count is essential, as there is a strong association between this count and certain opportunistic diseases that may manifest as fever of unknown origin. Imaging procedures, such as CT and radionuclide scans, are useful for the location of inflammatory and neoplastic lesions. Liver and bone marrow biopsies are helpful in certain subsets of patients and the efficacy of empirical treatments has been clearly documented in certain infections. Some HIV-infected patients with fever of unknown origin remain undiagnosed after a thorough investigation; these individuals should be managed conservatively. Finally, symptomatic treatment is the best option for terminally ill patients in whom benefit from a detailed investigation of the cause of fever is not expected.

Cutaneous lesions in patients with visceral leishmaniasis and HIV infection

Cutaneous lesions attributed to Leishmania are very seldom observed in classic Kala-Azar, but recently some reports have mentioned them in patients with HIV infection. We found cutaneous lesions whose biopsy disclosed the presence of Leishmania organisms in six patients of a group of 32 HIV patients with visceral Leishmaniasis. These lesions did not present a uniform or specific appearance, even though they tended to localize symmetrically on acral zones. They consisted of erythematous papules and hypopigmented macules on the dorsa of the hands, feet, and elbows; small subcutaneous nodules on the thighs; and erythematoviolaceous, scaly plaques on the face. These lesions accompanied in every case the other symptoms and/or signs of visceral leishmaniasis, responded to anti-leishmanial treatment, and were sometimes the first indicator of recurrence. The histopathological study was non-specific, but showed in every case the presence of abundant amastigotes within the dermal histiocytes and free in the dermis or subcutaneous tissue. Data from literature review are similar to ours.

Antiprotozoal compounds from Asparagus africanus

Two antiprotozoal compounds have been isolated from the roots of Asparagus africanus Lam. (Liliaceae), a new sapogenin, 2 beta, 12 alpha-dihydroxy-(25R)-spirosta-4,7-dien-3-one (1), which was named muzanzagenin, and the lignan (+)-nyasol (2), (Z)-(+)-4,4'-(3-ethenyl-1-propene-1,3-diyl)-bisphenol. The structure of the sapogenin was elucidated by MS and by 1D and 2D NMR methods and established by a single crystal X-ray analysis. (+)-Nyasol potently inhibits the growth of Leishmania major promastigotes, the IC50 being 12 microM, and moderately inhibits Plasmodium falciparum schizonts with the IC50 49 microM. These concentrations only moderately affect the proliferation of human lymphocytes. Muzanzagenin showed a moderate in vitro activity in all three tests, the IC50 against leishmania promastigotes was 70 microM, and against four different malaria schizont strains the IC50 values were 16, 163, 23, and 16 microM, respectively.

Pyrexia of undetermined origin in advanced HIV disease

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The pancreas in AIDS

Although autopsy studies reveal significant pancreatic lesions in about 10% of AIDS patients, pancreatic lesions infrequently produce symptoms and are rarely recognized premortem. Patients with AIDS can develop pancreatic disease from causes not related to AIDS or AIDS-specific lesions. AIDS-specific causes include opportunistic infection, AIDS-associated neoplasia, and medications used to treat complications of AIDS. Pancreatic involvement is usually part of a widely disseminated tumor and rarely produces clinical symptoms.

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.

Duodenal leishmaniasis diagnosed by biopsy in two HIV-positive patients

We describe two cases of duodenal leishmaniasis in patients with human immunodeficiency virus (HIV) infection, diagnosed by light and electron microscopy. The patients presented nonspecific signs and symptoms, blood cultures were sterile, and serological tests for Leishmania spp. were negative. Endoscopy showed normal-appearing mucosa in one patient and possible peptic duodenitis in the other patient. In these patients, the parasite was only detected in a duodenal biopsy specimen. In view of the unusual location of the parasite and the fact that the diagnostic and dissemination of the disease was established by means of conventional biopsy, this is not a routine procedure for the diagnosis of leishmaniasis because the classic procedures require the demonstration of antibodies and visualization in bone marrow, lymph nodes, liver and/or spleen aspirates. We decided to report these two cases to call attention to the possible finding of Leishmania amastigotes in biopsies from intestinal mucosa in HIV infected patients.

In vivo efficacy of oral and intralesional administration of 2-substituted quinolines in experimental treatment of new world cutaneous leishmaniasis caused by Leishmania amazonensis

The antileishmanial efficacies of 2-n-propylquinoline, chimanines B and D, 2-n-pentylquinoline, 2-phenylquinoline, 2-(3,4-methylenedioxyphenylethyl) quinoline, and two total alkaloidal extracts of Galipea longiflora were evaluated in BALB/c mice infected with Leishmania amazonensis or Leishmania venezuelensis. Animals were treated for 4 to 6 weeks postinfection with a quinoline by the oral route at 50 mg/kg of body weight twice daily for 15 days or by five intralesional injections at intervals of 4 days with a quinoline at 50 mg/kg of body weight. The reference drug, N-methylglucamine antimonate (Glucantime), was administered by subcutaneous or intralesional injection (regimens of 14, 28, or 56 mg of pentavalent antimony [Sbv] per kg of body weight daily). Twice-daily oral treatment with chimanine B at 50 mg/kg resulted in a decrease in lesion weight by 70% (P < 0.001) and a decrease in the parasite loads by 95% (P < 0.001). Five injections of chimanine B at intervals of 4 days reduced the lesion weight by 74% and the parasite loads in the lesion by 90% compared with the values for the group of untreated mice. Subcutaneous administration of N-methylglucamine antimonate at 28 mg of Sbv kg per day for 15 days reduced the parasite burden by 95% (P < 0.001), and five intralesional injections at the same concentration reduced the parasite burden by 96% (P < 0.001). Other 2-substituted quinolines, 2-n-propylquinoline administered by the oral and intralesional routes, 2-phenylquinoline administered by the oral route, 2-n-pentylquinoline administered by intralesional injection, and two total alkaloidal extracts of G. longiflora administered by the oral route, had intermediate effects. These findings suggest that chimanine B may be chosen as a lead molecule in the development of oral therapy against leishmaniasis.

Prospective evaluation of fever of unknown origin in patients infected with the human immunodeficiency virus. Grupo Andaluz para el Estudio de las Enfermedades Infecciosas

The aim of this study was to determine the frequency and aetiology of fever of unknown origin (FUO) in patients infected with the human immunodeficiency virus (HIV), to assess the value of the tests used in its diagnosis, and to evaluate possible models of diagnosis for the causes found most frequently. One hundred twenty-eight (3.5%) of 3603 hospitalised HIV-positive patients evaluated from October 1992 to December 1993 had FUO, defined by established criteria. Eighty-six percent of patients with FUO had previously progressed to AIDS. The median CD4+ cell count was 46/mm3. A definite diagnosis was made in 96 (75%) of the 128 patients and a possible diagnosis in 24 (18.7%). whilst no diagnosis was made in eight cases (6.2%). Tuberculosis (48.3%), visceral leishmaniasis (16%), and infection by Mycobacterium avium complex (6.9%) were the diseases found most frequently. The most useful diagnostic tests were liver biopsy (68.9%) and bone marrow aspirate/biopsy (39.7%). It is not possible to predict clinically the cases of FUO due to tuberculosis, whilst thrombocytopaenia < 100,000 cells/mm3 alone is useful for differentiating the cases of visceral leishmaniasis, with a negative predictive value of 95.2%.

One patient, two unusual conditions and three basic lessons

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Prophylaxis of visceral leishmaniasis in human immunodeficiency virus-infected patients

OBJECTIVE

To assess the effectiveness of two regimens with allopurinol or pentavalent antimony as secondary prophylaxis for visceral leishmaniasis (VL) in human immunodeficiency virus (HIV)-infected patients.

DESIGN

Retrospective, nonrandomized, open trial.

SETTING

A 1,000-bed academic tertiary institutional hospital in Barcelona.

PATIENTS

Forty-six individuals over 14 years old with HIV infection, who recovered from an episode of VL between January 1988 and February 1995.

INTERVENTIONS

Twenty patients did not receive any prophylaxis, nine received 300 mg/8 h of allopurinol, and 17 received 850 mg once-a-month of pentavalent antimony. Patients were followed-up every 3 months, and the endpoint of study was relapse of VL.

RESULTS

Twenty-one patients had recurrent VL: 13 of 20 in the control group (65%), 5 of 9 in the allopurinol group (56%), and 3 of 17 in the antimonial group (18%). Kaplan-Meier estimates of the probability of remaining relapse-free at 12 months were 9% without prophylaxis (95% CI, 0-22%), 21% with allopurinol (95% CI, 0-51%), and 93% with antimonials (95% CI, 82-100%) (P < 0.001). Multivariate analysis showed that the only significant variables related to relapsing course of VL were assignment to the antimonial group, and the fact that the patient had experienced a previous episode of VL.

CONCLUSIONS

Pentavalent antimony given once a month is effective in the prevention of VL relapses in HIV-infected individuals. It is a low-cost treatment that proved to be well tolerated. Therefore, pentavalent antimony should be considered a suitable agent for secondary prophylaxis against VL.

L-alanine: 4,5-dioxovalerate transaminase in Leishmania donovani that differs from mammalian enzyme

Leishmania protozoans are the causative agents of leishmaniasis, a major parasitic disease in humans. The parasites manifest a nutritional requirement for heme compounds since they are deficient in heme biosynthesis. In this study we have demonstrated for the first time the presence of the enzyme L-alanine: 4,5-dioxovalerate transaminase in Leishmania donovani. This enzyme catalyzes the synthesis of 5-aminolevulinic acid (ALA), the first committed step in heme synthesis. Thus the defect in heme biosynthesis pathway in Leishmania must lie at some enzymatic level subsequent to synthesis of ALA. The enzyme was found to be present in both virulent and avirulent strains of L. donovani. The virulent promastigotes showed a 41% higher specific activity as compared to the avirulent strain. The enzyme activity was found to be inhibited in the presence of heme and methylglyoxal. Immunoblot analysis revealed that L-alanine: 4,5-dioxovalerate transaminase in L. donovani was immunologically different from that in mammals.

A highly sensitive and rapid procedure for direct PCR detection of Leishmania infantum within human peripheral blood mononuclear cells

We have developed a highly sensitive, simple and rapid procedure to detect Leishmania infantum within human macrophages. It only requires ficoll preparation of peripheral blood mononuclear cells from the patient, and their direct use for Leishmania kDNA amplification by polymerase chain reaction. Under these conditions, about one parasite can be detected in a one million human cell environment. Results, including those of a hybridization step to confirm the diagnosis specificity, are obtained with 24 h, a very short period as compared to current diagnostic methods. This procedure is of particular interest for early detection and early drug treatment of leishmaniasis, especially in the case of HIV coinfection. Furthermore, the method could be useful for monitoring the efficiency of new leishmaniasis treatments in infected patients.

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.