Clinical and histological kidney involvement in human kala-azar

Neglected and Emerging Infections of The Kidney

Individuals, societies, and the environment are affected by neglected and emerging diseases. These diseases result in a variety of severe outcomes, including permanent disabilities, chronic diseases such as chronic kidney disease, and even mortality. Consequences include high health care expenditures, loss of means of support, social stigma, and social exclusion. The burden of these diseases is exacerbated in low- and middle-income countries owing to poverty, inadequate fundamental infrastructure, and the absence of health and social protection systems. The World Health Organization is committed to promoting the following public health strategies to prevent and control neglected tropical diseases: preventive chemotherapy; intensive case management; vector control; provision of safe drinkable water, sanitation, and hygiene; and veterinary public health. In addition, it promotes a One Health strategy, which is a collaborative, multisectoral, and interdisciplinary approach to achieving the greatest health outcomes by recognizing the interdependence of human beings, animals, plants, and their shared environment. This article provides knowledge and strategies for the prevention and treatment of neglected and emerging diseases, with a particular concentration on kidney diseases, as part of a comprehensive approach to One Health.

Evaluation of Renal Function Profile in Human Visceral Leishmaniasis (Kala-Azar) Patients: A Case of Western Tigray, Ethiopia

Background

Leishmaniasis is a vector-borne protozoan infection that has a wide clinical spectrum in the tropics and subtropics. Kidney damage is frequently associated with increased morbidity and mortality in visceral leishmaniasis (VL) patients. However, up to date, there is a very limited report on the effect of visceral leishmaniasis on kidney function profiling in Ethiopia.

Objective

To evaluate the renal function profile in human visceral leishmaniasis (kala-azar) patients.

Materials and Methods

Human blood was taken from VL patients (n = 100) and healthy controls (n = 100) attending Kahsay Abera and Mearg Hospitals, Western Tigray of Ethiopia. Serum was separated according to the conventional protocol and kidney function profiling (creatinine, urea, and uric acid) was analyzed by Mindray 200E automated chemistry analyzer. The estimated glomerular filtration rate (eGFR) was also assessed in this study. The obtained data were processed using SPSS Version 23.0. Descriptive statistics, independent-test, and bivariate correlations were used for data analysis. P values <0.05 were considered statistically significant at a 95% confidence level.

Results

The mean serum creatinine level was found significantly higher, while respective serum urea and eGFR were significantly lower in VL patients compared to healthy controls. Specifically, from 100 VL cases, an increased level of serum creatinine, urea, and uric acid was found in 10%, 9% and 15% VL cases, respectively; meanwhile, a decreased serum urea and eGFR have been reported from 33% to 44% VL cases, respectively.

Conclusion

The finding of this study asserted that visceral leishmaniasis causes derangement in kidney activities characterized by alteration of renal function profile. This may indicate that VL is the determinant factor for developing kidney dysfunction. This study encourages researchers to engage in visceral leishmaniasis and its effect on other organ function profiles in humans and identify potential markers for both prevention and intervention.

Leishmania (L.) infantum BH401 strain induces classic renal lesions in dogs: Histological and confocal microscopy study

Extracellular matrix (ECM) alterations in visceral leishmaniasis are related mainly to collagen deposition (fibropoiesis). In canine visceral leishmaniasis (CVL), an intense fibrosis associated to chronic inflammation in organs such as kidneys is described. However, renal fibropoiesis has not been described in natural or experimental infections with L. (L.) infantum. We aimed to characterize renal nephropathies by histology and confocal microscopy comparing renal lesions in dogs naturally and experimentally infected with L. (L.) infantum. Sixty-two mixed-breed symptomatic dogs naturally infected with L. (L.) infantum, sixteen beagles experimentally infected with two strains of L. infantum (eleven dogs with the BH400 strain and five dogs with the BH401 strain), and four uninfected beagles (controls) were used. Samples were stained with hematoxylin & eosin for routine histology. Congo red was used to visualize amyloid protein deposits, periodic acid-Schiff to identify glomerular basal membrane anomalies, Masson's trichrome for collagen deposits, and Jones' methenamine silver to reveal membranous glomerulonephropathy. Immunohistochemistry was used to identify Leishmania amastigotes, and confocal microscopy was used for macrophage characterization (L1/calprotectin and CD163 antigen receptors). The most common lesions were chronic glomerular and interstitial nephritis, which was found in all naturally infected dogs and dogs experimentally infected with L. infantum strain BH401 but not with the BH400 strain. Glomeruloesclerosis was the main lesion presented in all BH401 group. Morphometric analysis revealed positive correlation of renal glomeruli tufts with cellular expression of L1/calprotectin and CD163 antigens. Leishmania infantum strain BH401 shows pathogenicity that may be sufficient to induce classic chronic visceral renal leishmaniasis.

Acute kidney injury in patients with Visceral Leishmaniasis in Northwest Ethiopia

BACKGROUND

Visceral Leishmaniasis (VL) is a neglected tropical disease endemic to several countries including Ethiopia. Outside of Africa, kidney involvement in VL is frequent and associated with increased mortality. There is however limited data on acute kidney injury (AKI) in VL patients in East-Africa, particularly in areas with high rates of HIV co-infection. This study aims to determine the prevalence, characteristics and associated factors of AKI in VL patients in Northwest Ethiopia.

METHODS

A hospital based retrospective patient record analysis was conducted including patients treated for VL from January 2019 to December 2019 at the Leishmaniasis Research and Treatment Center (LRTC), Gondar, Ethiopia. Patients that were enrolled in ongoing clinical trials at the study site and those with significant incomplete data were excluded. Data was analyzed using SPSS version 20. P values were considered significant if < 0.05.

RESULTS

Among 352 VL patients treated at LRTC during the study period, 298 were included in the study. All were male patients except two; the median age was 23 years (IQR: 20-27). The overall prevalence of AKI among VL patients was 17.4% (confidence interval (CI): 13.6%-22.2%). Pre-renal azotemia (57%) and drug-induced AKI (50%) were the main etiologies of AKI at admission and post-admission respectively. Proteinuria and hematuria occurred in 85% and 42% of AKI patients respectively. Multivariate logistic regression revealed HIV co-infection (adjusted odds ratio (AOR): 6.01 95% CI: 1.99-18.27, p = 0.001) and other concomitant infections (AOR: 3.44 95% CI: 1.37-8.65, p = 0.009) to be independently associated with AKI.

CONCLUSION

AKI is a frequent complication in Ethiopian VL patients. Other renal manifestations included proteinuria, hematuria, and pyuria. HIV co-infection and other concomitant infections were significantly associated with AKI. Further studies are needed to quantify proteinuria and evaluate the influence of AKI on the treatment course, morbidity and mortality in VL patients.

Immunohistochemical study of renal fibropoiesis associated with dogs naturally and experimentally infected with two different strains of Leishmania (L.) infantum

The objectives of this work were to study some pathological aspects of kidneys obtained from dogs naturally infected with Leishmania infantum and from dogs experimentally infected with two different strains of L infantum with special emphasis on fibrotic process. Seventy eight specimens of paraffin-embedded kidney fragments were collected as follows: (a) CNI group composed by 62 kidney samples of adult mongrel dogs, naturally infected with L infantum; (b) BH401 group composed by five kidney samples of adult Beagles experimentally infected with L infantum strain MCAN BR/2002/BH401; (c) BH400 group composed by eleven kidney samples of adult Beagles experimentally infected with L infantum strain MCAN/BR/2000/BH400, at the same dose and same route of the previous group, denominated group BH400; Control group (CC) composed by four kidney samples of adult Beagles. All animals revealed glomerular and interstitial fibropoiesis associated with different types of glomerulonephritis and chronic interstitial nephritis. Fibrosis was markedly more intense in the BH401 group, followed by animals in the CNI group. Markers for myofibroblasts (mesenchymal markers) such as alpha-actin (α-SMA), vimentin and the cytokine transforming growth factor beta (TGF-β) were done by immunohistochemistry. BH401 group showed higher expression of all these markers than others. Intracellular amastigotes forms of Leishmania was mainly found in BH401. These results could be indicating that the MCAN/BR/2002/BH401 strain is a good choice for the study of renal LVC experimental model.

Microalbuminuria and glomerular filtration rate in paediatric visceral leishmaniasis

Visceral leishmaniasis, caused by Leishmania donovani, is a serious form of leishmaniasis and fatal if untreated. Nearly half of the VL cases are children. There are very few studies of renal function in pediatric visceral leishmaniasis. The aim of this study was to evaluate renal dysfunction by studying glomerular filtration rate (GFR), microalbuminuria, and microscopic examination of urine. Laboratory analysis was performed on blood and urine samples of 40 parasitologically confirmed pediatric VL cases. Laboratory data of urine examination showed albuminuria in 10% (4/40), white blood cells in 20% (8/40), hematuria in 10% (4/40), microalbuminuria in 37.5% (15/40), and decreased GFR in 27.5% (11/40). Renal involvement was manifested in most of the pediatric VL cases. These findings may help clinicians in decision making for safe and suitable antileishmanial treatment particularly in childhood VL.

Renal involvement in leishmaniasis: a review of the literature

Leishmaniasis, an infectious disease endemic in tropical, Asian and southern European countries, is caused by obligate intramacrophage protozoa and is transmitted through the bite of infected female sandflies. More than 20 leishmanial species are responsible for four main clinical syndromes: cutaneous leishmaniasis; mucocutaneous leishmaniasis; visceral leishmaniasis, also known as kala-azar, and post-kala-azar dermal leishmaniasis. Visceral leishmaniasis can present with varying clinical features and the kidney can also be involved. Both glomerular and tubular function can be altered and patients can develop proteinuria, haematuria, abnormalities in urinary concentration and acidification and acute and chronic renal insufficiency. Not only the disease itself but also the therapy administered might be responsible for the renal involvement in kala-azar. Indeed, some of the agents with efficiency against visceral leishmaniasis, such as pentavalent antimonial drugs, amphotericin B, pentamidine, miltefosine, paromomycin and simataquine, may be associated with a high risk of renal toxicity. In this article, the literature on renal involvement in visceral leishmaniasis is reviewed.

T cells, adhesion molecules and modulation of apoptosis in visceral leishmaniasis glomerulonephritis

BACKGROUND

Immune complex deposition is the accepted mechanism of pathogenesis of VL glomerulopathy however other immune elements may participate. Further in the present study, no difference was seen between immunoglobulin and C3b deposit intensity in glomeruli between infected and non-infected dogs thus T cells, adhesion molecules and parameters of proliferation and apoptosis were analysed in dogs with naturally acquired VL from an endemic area. The dog is the most important domestic reservoir of the protozoa Leishmania (L.) chagasi that causes visceral leishmaniasis (VL). The similarity of VL manifestation in humans and dogs renders the study of canine VL nephropathy of interest with regard to human pathology.

METHODS

From 55 dogs with VL and 8 control non-infected dogs from an endemic area, kidney samples were analyzed by immunohistochemistry for immunoglobulin and C3b deposits, staining for CD4+ and CD8+ T cells, ICAM-1, P-selectin and quantified using morphometry. Besides proliferation marker Ki-67, apoptosis markers M30 and TUNEL staining, and related cytokines TNF-alpha, IL-1alpha were searched and quantified.

RESULTS

We observed similar IgG, IgM and IgA and C3b deposit intensity in dogs with VL and non-infected control dogs. However we detected the Leishmania antigen in cells in glomeruli in 54, CD4+ T cells in the glomeruli of 44, and CD8+ T cells in 17 of a total of 55 dogs with VL. Leishmania antigen was absent and T cells were absent/scarse in eight non-infected control dogs. CD 4+ T cells predominate in proliferative patterns of glomerulonephritis, however the presence of CD4+ and CD8+ T cells were not different in intensity in different patterns of glomerulonephritis. The expression of ICAM-1 and P-selectin was significantly greater in the glomeruli of infected dogs than in control dogs. In all patterns of glomerulonephritis the expression of ICAM-1 ranged from minimum to moderately severe and P-selectin from absent to severe. In the control animals the expression of these molecules ranged from absent to medium intensity. It was not observed any correlation between severity of the disease and these markers. There was a correlation between the number of Leishmania antigen positive cells and CD4+ T cells, and between the number of CD4+ T cells and CD8+ T cells. In dogs presenting different histopathological patterns of glomerulonephritis, parameters of proliferation and apoptosis were studied. Ki-67, a proliferative marker, was not detected locally, but fewer apoptotic cells and lower TNF-alpha expression were seen in infected animals than in non-infected controls.

CONCLUSION

Immunopathogenic mechanisms of VL glomerulonephritis are complex and data in the present study suggest no clear participation of immunoglobulin and C3b deposits in these dogs but the possible migration of CD4+ T cells into the glomeruli, participation of adhesion molecules, and diminished apoptosis of cells contributing to determine the proliferative pattern of glomerulonephritis in VL.

Risk factors for acute kidney injury in visceral leishmaniasis (Kala-Azar)

The aim of this study was to investigate the factors associated with acute kidney injury (AKI) in patients with visceral leishmaniasis (VL). The study patients had a diagnosis of VL and were admitted to a tertiary hospital. A multivariate analysis was performed to analyze the risk factors for AKI. A total of 224 patients were included. The mean age was 36 +/- 15 years. AKI was observed in 33.9% of cases. Risk factors associated with AKI were male gender (odds ratio [OR] = 2.2; P = 0.03), advanced age (OR = 1.05; P < 0.001), and jaundice (OR = 2.9; P = 0.002). There was an association between amphotericin B use and AKI (OR = 18.4; P < 0.0001), whereas glucantime use was associated with lower incidence of AKI compared with amphotericin B use (OR = 0.05; P < 0.0001). Mortality was 13.3%, and it was higher in AKI patients (30.2%). Therefore, factors associated with AKI were male gender, advanced age, and jaundice. Amphotericin B was an important cause of AKI in VL.

Renal injury due to hepatic hydatid disease

BACKGROUND

Many studies on renal hydatid disease have been reported in the literature, and the disease process appears to be well defined. However, renal injury without direct renal invasion remains poorly understood. The present study aims to define the frequency and the property of the renal involvement in hydatid disease.

METHODS

Eighty patients older than 18 years and diagnosed with liver echinococcosis were included in the study. The echinococcosis was diagnosed by the haemagglutination test and abdominal ultrasonography. Twenty-four-hour protein excretion was measured for patients who had elevated serum creatinine levels or whose urinalyses were positive for haematuria or proteinuria. Subsequently, renal biopsy was performed, and the specimens were examined by light microscopy and immunofluorescence staining.

RESULTS

Haematuria was detected in 11 patients (13.75%), and proteinuria was detected in nine patients (11.25%). Percutaneous renal biopsy was applied to nine patients who gave signed consents to undergo the test. We detected four immunoglobulin A nephritis (together with tubulointerstitial nephritis in one patient), one membranoproliferative glomerulonephritis, one immunoglobulin M nephritis together with mesangiocapillary glomerulonephritis, one membranous glomerulonephritis, one amyloidosis and one tubulointerstitial nephritis. Renal hydatid cyst was detected only in four patients (5%).

CONCLUSIONS

Hydatid disease, which affects the kidney, is not rare, and we suggest that urinalysis and, if indicated, renal biopsy should be performed for hepatic hydatid disease diagnosis.

Microscopic evaluation of renal changes in experimental canine visceral leishmaniosis after chemo- and immunotherapy

Visceral Leishmania (VL) with diverse clinical manifestation is prevalent and remains a major public health problem in Iran. This study was performed in Ahwaz, Khozestan province southwest to increase immune system and to reduce of the renal lesions. Treatment of dogs with visceral leishmaniosis is basically the same as the treatment of human. However, cure is not usually achieved, leaving the sacrifice of animal as the only feasible choice. The goal of this work was to test the therapeutic efficacy of N-methyl glutamic antimoate (glucnime), Mycobacterium vaccae adjuvant (SRL 172), alone and in association with L. major promastigote and the latter compound in association to glucantime, in dog with visceral leishmaniasis. In this trial 18, mixed bred dogs with different ages, receiving amastigte promastigote of L. infantum intravenously were used. They were monitored for 6 months. Serologic assays (Elisa, Dot and IFAT) were performed on blood samples of each animal. The animals were divided into six groups, each having 3 dogs: Group 1: receiving 100 mg kg(-1) day(-1) Glucantime for 30 days, IM. Group 2: Receiving 3 mg dog(-1) (0.1 mL) of Mycobacterium vaccae adjuvant suspension intradermaly. Group 3: receiving L. major promastigote plus M. vaccae adjuvant each of them 0.1 mL intradermaly by one month intervals for 3 months. Group 4: receiving Glucantime in association L. major promastigote plus M. vaccae adjuvant with previous doses. Group 5: Receiving no treatment. Group 6: was control group with no infection and treatment. In microscopic evaluation following lesions have been shown in kidney: Chronic, interstitial nephritis, sever glomerulosclerosis, membranoproliferative glomerulonephritis and also non suppurative nephritis were the lesions in 5 groups. The prescription of Mycobacterium vaccae adjurant was able to reduce the number of parasites in the macrophages of liver and spleen in this round of treatment.

Leishmania (Leishmania) chagasi-infected mice as a model for the study of glomerular lesions in visceral leishmaniasis

Renal involvement in visceral leishmaniasis (VL) is very frequent but the pathogenesis of this nephropathy is poorly understood. In previous studies using dogs with VL we have detected new immunopathological elements in the glomeruli such as T cells and adhesion molecules. Although Leishmania (Leishmania) chagasi-infected dogs and hamsters are considered to be good models for VL, their use is limited for immunopathologic studies. The use of isogenic mouse strains susceptible to L. (L.) chagasi infection was an alternative but, on the other hand, the renal lesions of these animals have not yet been characterized. Thus, our purpose in the present study was to characterize mice infected with L. (L.) chagasi as a suitable model to study VL nephropathy. Kidney samples were obtained from control mice (N = 12) and from BALB/c mice (N = 24) injected intraperitoneally with 20 million L. (L.) chagasi amastigotes 7, 15, and 30 days after injection and processed for histopathological studies and detection of IgG deposits. Glomerular hypercellularity was clearly visible and, upon Mason's trichrome and periodic acid methenamine silver staining, a pattern suggestive of mesangial proliferative glomerulonephritis was observed in mice with VL. Time-dependent IgG deposits were also seen in infected mice. We consider L. (L.) chagasi-infected mice to be a suitable model for studies of the immunopathogenesis of glomerular lesions in VL.

Histopathologic patterns of nephropathy in naturally acquired canine visceral leishmaniasis

Although the nephropathy of visceral leishmaniasis (VL) is known both in humans and dogs, histopathologic alterations have not been thoroughly studied. We examined renal alterations in 55 dogs with naturally acquired VL compared with five noninfected dogs from an endemic area in northeastern Brazil. Glomerulonephritis was found in 55 dogs, interstitial alterations in 53 dogs, and tubular changes in 43 dogs with VL. The glomerular alterations found were minor glomerular abnormalities (n = 8, 14.5%), focal segmental glomerulosclerosis (n = 10, 18.2%), mesangial proliferative glomerulonephritis (n = 17, 32.7%), membranoproliferative glomerulonephritis, (n = 18, 30.9%), crescentic glomerulonephritis (n = 1, 1.8%), and chronic glomerulonephritis (n = 1, 1.8%). Morphometric and ultrastructural studies complemented the analysis. The five control animals exhibited no glomerular alterations. The glomerular lesions were related to functional alterations. Considering that the alterations of canine and human nephropathy in VL are very similar, the data obtained in this study constitute an important contribution to the understanding of canine and human VL nephropathy.

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.

Pathology of renal diseases in the tropics

Renal diseases unique to the tropics are those that occur in association with infectious diseases including dengue hemorrhagic fever, typhoid fever, shigellosis, leptospirosis, lepromatous leprosy, malaria, opisthorchiasis, and schistosomiasis. These renal complications can be classified on the basis of their clinical and pathologic characteristics into acute transient reversible glomerulonephritis, chronic progressive irreversible glomerulonephritis, amyloidosis, and acute renal failure (ARF) resulting from acute tubular necrosis, acute tubulointerstitial nephritis, and thrombotic microangiopathy. Certain primary glomerular diseases including immunoglobulin (Ig) M nephropathy and focal segmental and global glomerulosclerosis are prevalent in some tropical countries. Renal complications of venomous snakebites also are common in the tropics. This article discusses and summarizes important works in the literature in respect to the clinical syndromes, pathologic features, and pathogenesis of tropical renal diseases both in humans and experimental animal models.

Detection of immunoglobulin G in the lung and liver of hamsters with visceral leishmaniasis

Several organs are affected in visceral leishmaniasis, not only those rich in mononuclear phagocytes. Hypergammaglobulinemia occurs during visceral leishmaniasis; anti-Leishmania antibodies are not primarily important for protection but might be involved in the pathogenesis of tissue lesions. The glomerulonephritis occurring in visceral leishmaniasis has been attributed to immune complex deposition but in other organs the mechanism has not been studied. In the current study we demonstrated the presence of IgG in the lung and liver of hamsters with visceral leishmaniasis. Hamsters were injected intraperitoneally with 2 x 10(7) amastigotes of Leishmania (Leishmania) chagasi and the presence of IgG in the liver and lung was evaluated at 7, 15, 30, 45, 80 and 102 days postinfection (PI) by immunohistochemistry. The parasite burden in the spleen and liver increased progressively during infection. We observed a deposit of IgG from day 7 PI that increased progressively until it reached highest intensity around 30 and 45 days PI, declining at later times. The IgG deposits outlined the sinusoids. In the lung a deposit of IgG was observed in the capillary walls that was moderate at day 7 PI, but the intensity increased remarkably at day 30 PI and declined at later times of infection. No significant C3 deposits were observed in the lung or in the liver. We conclude that IgG may participate in the pathogenesis of the inflammatory process of the lung and liver occurring in experimental visceral leishmaniasis and we discuss an alternative mechanism other than immune complex deposition.

Crossing of antinuclear antibodies and anti-leishmania antibodies

Visceral leishmaniasis or Kala-azar is an endemic parasitic infection in Mediterranean countries. We report an interesting case occurring in a 38-year-old woman suffering from systemic lupus erythematosus and secondary antiphospholipid syndrome. In our patient visceral leishmaniasis occurred during high dose-steroids treatment mimicking a flare of lupus. As the lupus resolved under immunosuppressive treatment, a reactivation of visceral leishmaniasis was observed and was confirmed by the successive serological tests which showed crossing of leishmania and antinuclear antibody titers. Our case shows that, faced with fever occurring in lupus patients in an endemic area, visceral leishmaniasis should be searched for before intensifying immunosuppressive treatments.

CD4(+) T cells participate in the nephropathy of canine visceral leishmaniasis

Renal involvement in visceral leishmaniasis (VL) is very frequent. The renal lesions of humans and dogs are similar but their pathogenesis has not been clearly elucidated. There is growing evidence that the cellular immune response is involved in the pathogenesis of immunologically mediated glomerulonephritis. Since T cells could participate in the pathogenesis of nephropathy, in the present study we investigated the possible involvement of CD4(+) and CD8(+) T cells in the nephropathy of canine VL. Six dogs naturally infected with Leishmania (Leishmania) chagasi from the endemic area in the Northeast of Brazil, the town of Teresina in the State of Piauí, were studied. An expressive inflammatory infiltrate of CD4(+) T cells both in glomeruli and in interstitium was present in 4 animals and absent in 2. CD8(+) T cells were detected only in one animal. CD4(+) T cells alone were observed in 3 animals; when CD8+ T cells were present CD4(+) T cells were also present. CD4(+) T cells were observed in cases of focal segmental glomerulosclerosis, diffuse membranoproliferative glomerulonephritis, diffuse mesangial proliferative glomerulonephritis and crescentic glomerulonephritis. CD8(+) T cells were present only in a case of crescentic glomerulonephritis. Leishmania antigen was detected in glomeruli and in interstitial inflammatory infiltrate in 4 animals and immunoglobulins were observed in 4 dogs. In this study we observed that T cells, in addition to immunoglobulins, are present in the renal lesion of canine VL. Further studies are in progress addressing the immunopathogenic mechanisms involving the participation of immunoglobulins and T cells in canine VL nephropathy.

Mixed cryoglobulinemia secondary to visceral Leishmaniasis

We describe a case of type II mixed cryoglobulinemia, with monoclonal IgMkappa rheumatoid factor, associated with visceral leishmaniasis caused by Leishmania infantum. Involvement of Leishmania antigen(s) in the formation of cryoprecipitable immune complexes was suggested by the fact that cryoglobulinemic vasculitis subsided after antiparasite therapy and that anti-Leishmania antibodies, as well as rheumatoid factor, were enriched in the cryoprecipitate. We observed 2 additional patients with visceral leishmaniasis and cryoglobulinemic vasculitis. All 3 patients had seemingly contracted leishmaniasis in Italy, were hepatitis C virus negative, and were initially diagnosed as having autoimmune disorders. These findings indicate that Leishmania can be an etiologic agent of type II mixed cryoglobulinemia. This parasitosis should be taken into consideration in the differential diagnosis of vasculitides in endemic areas.

Pathological changes in kidneys of dogs with natural Leishmania infection

A study was made of the nephropathy in canine leishmaniasis produced in ten adult dogs naturally infected with Leishmania infantum. Renal function analyses were performed (uraemia, creatinaemia, plasma proteins, biochemistry and urinary sediment), the humoral immune response (fluorescent antibodies and levels of serum IgG, IgM and IgA) was assessed and histopathological studies were carried out. Correlation of the results showed acute renal insufficiency which was reversible in two animals (endotheliomesangial glomerulonephritis) and irreversible in four cases corresponding to glomerulonephritis in its Type I and Type II proliferative forms; extensive increase in the glomerular basal membrane, proliferation of mesangial cells and growth of the mesangial matrix were observed, as was a widespread incidence of immune complex deposits. Two animals showed chronic renal insufficiency. Lack of renal changes (minimal-changes glomerulonephritis) in two dogs was accounted for in one animal by an almost complete absence of symptoms and in the other by chronic viscerocutaneous symptoms; neither showed more than a slight immunoglobulin response.

Immune complex glomerulonephritis in experimental kala-azar. II: Detection and characterization of parasite antigens and antibodies eluted from kidneys of Leishmania donovani-infected hamsters

In a previous report analysing kidney sections by immunofluorescence we showed that hamsters infected with L. donovani develop a glomerulonephritis (GN) associated with deposition of hamster immunoglobulins and parasite antigens in the glomeruli. In this study we characterize these immune components eluted from the kidneys. The eluted immunoglobulins showed specificity for L. donovani antigens and hamster immunoglobulins (rheumatoid factor-like activity). The four isotypes IgG1, IgG2, IgA and IgM were detected. Several L. donovani antigens were detected in the renal eluates by Western blot and immunoprecipitation using 125I-labelled eluates. Proteins with mol. wt of 134, 82, 52, 31, and 26 kD were detected by Western blot and proteins with 134, 110, 93, 89 and 48 kD were detected by immunoprecipitation. With the exception of the 134 kD protein which was recognized by both rabbit anti-promastigote and rabbit anti-amastigote sera all the others were recognized only by the anti-amastigote serum. The 134 kD protein was the only one isolated from the kidneys of infected hamster immunocomplexed with IgG and was the only one detected in a promastigote lysate using IgG from L. donovani-infected hamsters.

[Optical and electron microscopic study of the kidney of dogs naturally and experimentally infected with Leishmania (Leishmania) chagasi]

Two naturally infected dogs (male and female) from Teófilo Otoni (MG-Brazil) were maintained for 18 months in our laboratory. Two other dogs, two months old males were infected with 1 x 10(6) promastigotes of MHO/BR/70/BH46 Leishmania (Leishmania) chagasi strain, endovenous route, and autopsied after 10 months and two years. The main findings concerning the kidney were: (1) focal or diffuse mesangial glomerulonephritis with proliferative and enlargement of mesangial cells; (2) increase in thickness of basement membrane with electron-dense deposits; (3) chronic interstitial nephritis with intense exudation of plasmocytes; (4) cloud swelling of renal tubules. The authors discuss the probable pathogenetic mechanisms.

Identification of leishmanial antigens in the sera of patients with American visceral leishmaniasis

Circulating immune complexes are present in the sera of patients with visceral leishmaniasis caused by Leishmania donovani chagasi. In order to determine whether these complexes contain parasite antigens, sera were collected from Brazilian patients with visceral leishmaniasis and from hospitalized control subjects with other diagnoses. High-molecular-weight complexes were precipitated from pooled sera with 2.5% polyethylene glycol. Approximately 140-fold-more protein was precipitated from patient sera than from control sera; 12% of the total patient serum protein was precipitated. Patient serum precipitates contained immunoglobulins G (525 mg/dl), M (27 mg/dl), and A (8 mg/dl). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the patient serum precipitates revealed multiple bands, including a prominent band at 70 kilodaltons, that were not seen in precipitates of control sera. The 70-kilodalton band was recognized by human and hamster sera with antileishmanial antibodies, but not by control sera. Finally, immunization of BALB/c mice with the high-molecular-weight precipitates from patients elicited antileishmanial antibodies against L. donovani chagasi antigens as detected by enzyme-linked immunosorbent assay and Western blot (immunoblot) assay. In summary, sera of patients with American visceral leishmaniasis were found to have high-molecular-weight complexes that contained one or more parasite antigens. These complexes may play a role in the immunology of the disease, and detection of circulating parasite antigens has potential diagnostic importance.

Glomerulonephritis in dogs with canine leishmaniasis

Kidney specimens, obtained from 11 dogs of diverse species that had contracted spontaneous leishmaniasis, were submitted to a histopathological investigation using a classical preparation of sections embedded in paraffin, semi-thin and ultra-thin sections embedded in plastic, and sections frozen under immunofluorescence. Eight animals presented moderate to severe renal insufficiency. Two major categories of glomerular lesions were identified in the kidneys examined: acute glomerulonephritis and extra-membranous glomerulonephritis. These two categories were never associated and no transition from from one to the other was found. Immune complex deposits prevailed sharply over proliferative phenomena, which remained infrequent. Study of these glomerulonephrities could represent a model for better understanding of the immunological aspects of leishmaniasis.

Detection of Leishmania donovani soluble antigen and antibody in the urine of visceral leishmaniasis patients

Urine samples from 21 patients with visceral leishmaniasis were examined for the presence of Leishmania donovani soluble antigen and antibody by double counter-current immunoelectrophoresis. 19 samples revealed both antigen and antibody (IgM in 5 and IgG in all samples). 2 urine samples collected 10 and 13 days after Glucantime treatment revealed only antibody (IgG), not soluble antigen.

Immune complex glomerulonephritis in experimental kala-azar

In the present work we demonstrate that hamsters infected with L. donovani eliminate large quantities of immunoglobulins in the urine. This alteration is clearly a consequence of a conspicuous immune complex glomerulonephritis readily detectable 7 days after the beginning of infection. L. donovani antigens and hamsters immunoglobulins (Igs) were revealed as granular deposits in the mesangial areas and contiguous loops of the glomeruli. Histopathological alterations such as focal mesangial proliferation with progression to diffuse proliferation were observed in the first 3 weeks of infection. From day 35 onwards, all diseased animals presented large deposits of amyloid material of predominantly glomerular localization. In consonance with these alterations, Igs were detected in the urine by day 21 of infection and their concentration increased substantially with the progression of disease. In contrast, serum Igs increased until day 21, when their concentration dropped steadily.

Absence of clinical abnormalities suggesting renal involvement during the long-term course of visceral leishmaniasis

Abnormalities of renal function have been demonstrated inpatients with visceral leishmaniasis; although there was a trend toward normalization following antiparasitic therapy, some abnormalities persisted. With thepurpose of studying the long- term clinical course of renal involvement in visceral leishmaniasis, 32 patients with a diagnosis of this parasitic disease were evaluated in the endemic area and at least 6 months after the clinical cure of the disease and compared with a control group of 28 individuals. No patient had a history or clinical findings suggestive of renal disease and all were normotensive. Laboratory evaluation was normal in all except 3 patients with abnormal urinalysis. Mild proteinuria and microscopic hematuria were seen in a single urinalysis in one patient (although three other urinalysis were normal), and leucocyturia in two female patients. It was concluded that the renal involvement in visceral leishmaniasis is mild and transient, with normal renal function observed on long-term follow-up after cure of the parasitic infection.

Renal involvement in visceral leishmaniasis

In a prospective study of 50 patients with visceral leishmaniasis, laboratory abnormalities suggestive of renal involvement were not infrequent. Proteinuria and/or microscopic hematuria or pyuria were observed in 51% of such cases. Twenty-four hour urinary protein excretion was elevated in 57% of patients in all cases below 1g/24 hours. An abnormal acid-load test was demonstrated in 12 of 18 patients studied before therapy of the parasitic infection with N-methyl-glucamine. Of interest was the demonstration of tubulo-interstitial involvement in the renal histology of all seven patients studied; also, in five of seven patients there was a proliferative glomerulonephritis, usually mild, on histologic examination. In general, there was a tendency to subsidence of abnormal laboratory findings within one month after specific therapy. Renal involvement in visceral leishmaniasis was mild and seemed to revert with the cure of the leishmanial infection.

Leishmaniasis in Brazil. XIV. Leishmanial and trypanosomal IgA antibody in patients with leishmaniasis and Chagas's disease

Preserved sera from patients with various forms of leishmaniasis, acute and chronic Chagas's disease and from normal individuals were examined for the presence of IgG and IgA antibodies by the IFA test. The leishmanial antigen used in the IFA test was prepared from a hamster infected with the PH8 strain of Leishmania mexicana amazonensis; amastigotes were isolated from a skin lesion and fixed in formal phosphate-buffered saline-glucose for slide antigen. There were significantly more positive reactions with IgA conjugate in patients with mucocutaneous leishmaniasis than in those with other forms. There was no association between IgA and IgG titres. The only two sera with trypanosomal IgA antibody were from two patients with acute Chagas's disease but neither sera produced cytoplasmic or surface fluorescence of leishmanial amastigotes. The implications of the presence of leishmanial and trypanosomal IgA antibody is discussed in detail.