Human immunodeficiency virus infection and human African trypanosomiasis: a case-control study in Côte d'Ivoire

Case Report: Trypanosoma brucei Gambiense Human African Trypanosomiasis as the Cause of Fever in an Inpatient with Multiple Myeloma and HIV-1 Coinfection

We report the case of a 64-year-old woman found to have urban-acquired Trypanosoma brucei (T.b.) gambiense human African trypanosomiasis (HAT) as the cause of sustained fever starting 9 months after returning to Canada from Democratic Republic of the Congo, in the context of concomitant multiple myeloma and HIV-1 coinfection. Approaches for the management of both clinical stages of T.b. gambiense HAT are well defined for endemic settings using current diagnostics and treatments. However, few data inform the diagnosis and management of patients with bone marrow suppression from active malignancy, recent anticancer therapy, or HIV coinfection. We discuss the implications of immunosuppression for diagnosis and management of T.b. gambiense HAT.

Tissue Parasites in HIV Infection

PURPOSE OF REVIEW

The purpose of this review is to discuss the current knowledge of HIV and tissue parasite co-infection in the context of transmission enhancement, clinical characteristics, treatment, relapse, and clinical outcomes.

RECENT FINDINGS

The pathophysiology and clinical sequelae of tissue parasites in people living with HIV (PLWH) have been well described for only a handful of organisms, primarily protozoa such as malaria and leishmaniasis. Available published data indicate that the interactions between HIV and tissue parasites are highly variable depending on the infecting organism and the degree of host immunosuppression. Some tissue parasites, such as Schistosoma species, are known to facilitate the transmission of HIV. Conversely, uncontrolled HIV infection can lead to the earlier and more severe presentation of a variety of tissue parasites and can make treatment more challenging. Although much investigation remains to be done to better understand the interactions between consequences of HIV and tissue parasite co-infection, it is important to disseminate the current knowledge on this topic to health care providers in order to prevent, treat, and control infections in PLWH.

Health Considerations for HIV-Infected International Travelers

PURPOSE OF THE REVIEW

International travel continues to steadily increase, including leisure travel, travel to one's country of origin to visit friends and relatives, travel for service work, and business travel. Travelers with HIV may have an increased risk for travel-associated infections. The pre-travel medical consultation is an important means of assessing one's risk for travel-related health issues. The aim of this review is to provide an update on key health considerations for the HIV-infected traveler.

RECENT FINDINGS

Like all travelers, the HIV-infected traveler should adhere to behavioral precautions, including safety measures with food and water consumption, safe sexual practices, and arthropod bite avoidance. HIV is a risk factor for venous thromboembolism and patients should be educated regarding this risk. Most pre-travel vaccines are safe and immunogenic in HIV-infected individuals, though live vaccines should be avoided in patients with low CD4 counts. Malaria chemoprophylaxis is strongly recommended in patients with HIV traveling to endemic areas and no significant interactions exist between the commonly used prophylactic anti-malarial agents and anti-retroviral therapy (ART). Travelers with HIV, particularly those who are not on ART or who have low CD4 cell counts, may have increased risk for tuberculosis, malaria, enteric infections, visceral leishmaniasis, American trypanosomiasis, and endemic mycoses such as histoplasmosis, talaromycosis, and coccidioidomycosis. The immune status of the HIV-infected traveler should be assessed prior to travel along with the duration, itinerary, and activities planned during travel in order to carefully consider individual risk for travel-related health issues.

Tropical Parasitic Infections in Individuals Infected with HIV

PURPOSE OF REVIEW

Neglected tropical diseases share both geographic and socio-behavioral epidemiological risk factors with HIV infection. In this literature review, we describe interactions between parasitic diseases and HIV infection, with a focus on the impact of parasitic infections on HIV infection risk and disease progression, and the impact of HIV infection on clinical characteristics of tropical parasitic infections. We limit our review to tropical parasitic infections of the greatest public health burden, and exclude discussion of classic HIV-associated opportunistic infections that have been well reviewed elsewhere.

RECENT FINDINGS

Tropical parasitic infections, HIV-infection, and treatment with antiretroviral therapy alter host immunity, which can impact susceptibility, transmissibility, diagnosis, and severity of both HIV and parasitic infections. These relationships have a broad range of consequences, from putatively increasing susceptibility to HIV acquisition, as in the case of schistosomiasis, to decreasing risk of protozoal infections through pharmacokinetic interactions between antiretroviral therapy and antiparasitic agents, as in the case of malaria. However, despite this intimate interplay in pathophysiology and a broad overlap in epidemiology, there is a general paucity of data on the interactions between HIV and tropical parasitic infections, particularly in the era of widespread antiretroviral therapy availability.

SUMMARY

Additional data are needed to motivate clinical recommendations for detection and management of parasitic infections in HIV-infected individuals, and to consider the implications of and potential opportunity granted by HIV treatment programs on parasitic disease control.

Characteristics, behaviors and association between Human African Trypanosomiasis and HIV seropositivity among volunteer blood donors in a semi-rural area: A survey from Kikwit, the Democratic Republic of Congo

Blood safety is a major element in the strategy to control the HIV epidemic. The aim of this study was to determine the prevalence and the associated factors of a positive HIV test among blood donors and its association between Human African Trypanosomiasis in Kikwit, the Democratic Republic of Congo. A cross-sectional study was conducted between November 2012 and May 2013. An anonymous questionnaire was designed to extract relevant data. The average mean age of participants was 30 years. The majority were man (67.8%). The overall prevalence of HIV, syphilis, hepatitis B, hepatitis C and human African trypanosomiasis was respectively 3.2%, 1.9%, 1.6%, 1.3% and 1.3%. Alcohol intake, casual unprotected sex, not using condoms during casual sex, sex after alcohol intake and seroprevalence of human African trypanosomiasis were significantly associated with a positive HIV test result ( p<0.05). In this study, sexual risk behaviors were the major risk factors associated with positive HIV tests in blood donors living in Kikwit. It is important to raise awareness about HIV and voluntary blood donation in response to some observations noted in this study such as the low educational level of the blood donors, the low level of knowledge of HIV prevention methods.

Revisiting zoonotic human African trypanosomiasis control in Uganda

OBJECTIVES

Human migration and concomitant HIV infections are likely to bring about major changes in the epidemiology of zoonotic parasitic infections. Human African trypanosomiasis (HAT) control is particularly fraught with intricacies. The primarily zoonotic form, T.b. rhodesiense, and the non-zoonotic T.b. gambiense co-exist in Northern Uganda, leading to a potential geographic and genetic overlap of the two foci. This region also has the highest HIV prevalence in Uganda plus poor food security. We examine the bottlenecks facing the control program in a changed political and economic context.

METHOD

We searched the literature in July 2015 using three databases: MEDLINE, Google Scholar, and Web of Science.

FINDINGS

Decentralized zoonotic HAT control for animal reservoirs and vectors compromise sustainability of the control programs. Human transmission potential may be underestimated in a region with other endemic diseases and where an HIV-HAT epidemic, could merge two strains.

CONCLUSION

Our comprehensive literature review concludes that enhanced collaboration is imperative not only between human and animal health specialists, but also with political science. Multi-sectorial collaborations may need to be nurtured within existing operational national HIV prevention frameworks, with an integrated surveillance framework.

Clinical profiles, disease outcome and co-morbidities among T. b. rhodesiense sleeping sickness patients in Uganda

BACKGROUND

The acute form of Human African Trypanosomiasis (HAT, also known as Sleeping sickness) caused by Trypanosoma brucei rhodesiense has been shown to have a wide spectrum of focus specific clinical presentation and severity in East and Southern Africa. Indeed HAT occurs in regions endemic for other tropical diseases, however data on how these co-morbidities might complicate the clinical picture and affect disease outcome remains largely scanty. We here describe the clinical presentation, presence of co-infections, and how the latter impact on HAT prognosis.

METHODS AND FINDINGS

We carried out a retrospective analysis of clinical data from 258 sleeping sickness patients reporting to Lwala hospital between 2005 and 2012. The mean patient age was 28.6 years with a significant number of cases below 18 years (p< 0.0001). About 93.4% of the cases were diagnosed as late stage (p< 0.0001). The case fatality rate was 10.5% with post treatment reactive encephalopathys reported in 7.9% of the cases, of whom 36.8% eventually died. Fever was significantly (p = 0.045) higher in patients under 18 years. Of the early stage patients, 26.7% and 6.7% presented with late stage signs of sleep disorder and mental confusion respectively. Among the co-infections, malaria was significantly more prevalent (28.9%; p< 0.0001) followed by urinary tract infections (4.2%). Co-infections were present in 14.3% of in-hospital deaths, 38.5% of which were recorded as Malaria. Malaria was significantly more common in patients under 18 years (45.5%; p< 0.02), and was reported in 60% of the fatal cases in this age group.

CONCLUSIONS

We show a wide spectrum of sleeping sickness clinical presentation and disease outcome that was apparently not significantly influenced by concurrent infections. It would thus be interesting to determine the host and/or parasite factors that might be responsible for the observed diverse clinical presentation.

Overview of the effect and epidemiology of parasitic central nervous system infections in African children

Infections of the central nervous system are a significant cause of neurologic dysfunction in resource-limited countries, especially in Africa. The prevalence is not known and is most likely underestimated because of the lack of access to accurate diagnostic screens. For children, the legacy of subsequent neurodisability, which affects those who survive, is a major cause of the burden of disease in Africa. Of the parasitic infections with unique effect in Africa, cerebral malaria, neurocysticercosis, human African trypanosomiasis, toxoplasmosis, and schistosomiasis are largely preventable conditions, which are rarely seen in resource-equipped settings. This article reviews the current understandings of these parasitic and other rarer infections, highlighting the specific challenges in relation to prevention, diagnosis, treatment, and the complications of coinfection.

Clinical presentation of T.b. rhodesiense sleeping sickness in second stage patients from Tanzania and Uganda

Background

A wide spectrum of disease severity has been described for Human African Trypanosomiasis (HAT) due to Trypanosoma brucei rhodesiense (T.b. rhodesiense), ranging from chronic disease patterns in southern countries of East Africa to an increase in virulence towards the north. However, only limited data on the clinical presentation of T.b. rhodesiense HAT is available. From 2006-2009 we conducted the first clinical trial program (Impamel III) in T.b. rhodesiense endemic areas of Tanzania and Uganda in accordance with international standards (ICH-GCP). The primary and secondary outcome measures were safety and efficacy of an abridged melarsoprol schedule for treatment of second stage disease. Based on diagnostic findings and clinical examinations at baseline we describe the clinical presentation of T.b. rhodesiense HAT in second stage patients from two distinct geographical settings in East Africa.

Methodology/Principal Findings:

138 second stage patients from Tanzania and Uganda were enrolled. Blood samples were collected for diagnosis and molecular identification of the infective trypanosomes, and T.b. rhodesiense infection was confirmed in all trial subjects. Significant differences in diagnostic parameters and clinical signs and symptoms were observed: the median white blood cell (WBC) count in the cerebrospinal fluid (CSF) was significantly higher in Tanzania (134cells/mm³) than in Uganda (20cells/mm³; p<0.0001). Unspecific signs of infection were more commonly seen in Uganda, whereas neurological signs and symptoms specific for HAT dominated the clinical presentation of the disease in Tanzania. Co-infections with malaria and HIV did not influence the clinical presentation nor treatment outcomes in the Tanzanian study population.

Conclusions/Significance

We describe a different clinical presentation of second stage T.b. rhodesiense HAT in two distinct geographical settings in East Africa. In the ongoing absence of sensitive diagnostic tools and safe drugs to diagnose and treat second stage T.b. rhodesiense HAT an early identification of the disease is essential. A detailed understanding of the clinical presentation of T.b. rhodesiense HAT among health personnel and affected communities is vital, and awareness of regional characteristics, as well as implications of co-infections, can support decision making and differential diagnosis.

Sleeping sickness, or Human African Trypanosomiasis (HAT), caused by Trypanosoma brucei rhodesiense is one of the most neglected tropical diseases. It affects mainly rural, poor East African populations and has very high socio-economic impacts. T.b. rhodesiense HAT is an acute disease; patients quickly progress from the first stage, where trypanosomes are detectable in blood and lymph, to the second stage, where parasites penetrate the central nervous system. If left untreated, T.b. rhodesiense HAT is fatal. Disease control is hampered by the absence of sensitive diagnostic tools and safe drugs. Second stage patients can only be treated with melarsoprol, a highly toxic, arsenical drug. It is more difficult to treat patients successfully at advanced stages of the disease, and late onset of treatment should be avoided. Yet, most patients are treated for other conditions prior to HAT diagnosis. Therefore, it is important that health personnel in T.b. rhodesiense endemic regions have a detailed understanding of the clinical presentation of the disease and consider regional characteristics of T.b. rhodesiense HAT for decision making and differential diagnosis.

Low specificities of HIV diagnostic tests caused by Trypanosoma brucei gambiense sleeping sickness

The accuracy of diagnostic tests for HIV in patients with tropical infections is poorly documented. Human African trypanosomiasis (HAT) is characterized by a polyclonal B-cell activation, constituting a risk for false-positive reactions to diagnostic tests, including HIV tests. A retrospective study of the accuracy of HIV diagnostic tests was performed with 360 human African HAT patients infected with Trypanosoma brucei gambiense before treatment and 163 T. b. gambiense-infected patients 2 years after successful treatment in Mbuji Mayi, East Kasai, Democratic Republic of the Congo. The sensitivities, specificities, and positive predictive values (PPVs) of individual tests and algorithms consisting of 3 rapid tests were determined. The sensitivity of all tests was 100% (11/11). The low specificity (96.3%, 335/348) and PPV (45.8%, 11/24) of a classical seroconfirmation strategy (Vironostika enzyme-linked immunosorbent assay [ELISA] followed by line immunoassay) complicated the determination of HIV status, which had to be determined by PCR. The specificities of the rapid diagnostic tests were 39.1% for Determine (136/348); 85.3 to 92.8% (297/348 to 323/348) for Vikia, ImmunoFlow, DoubleCheck, and Bioline; and 96.6 to 98.3% (336/348 to 342/348) for Uni-Gold, OraQuick, and Stat-Pak. The specificity of Vironostika was 67.5% (235/348). PPVs ranged between 4.9 and 64.7%. Combining 3 different rapid tests resulted in specificities of 98.3 to 100% (342/348 to 348/348) and PPVs of 64.7 to 100% (11/17 to 11/11). For cured HAT patients, specificities were significantly higher for Vironostika, Determine, Uni-Gold, and ImmunoFlow. T. b. gambiense infection decreases the specificities of antibody detection tests for HIV diagnosis. Unless tests have been validated for interference with HAT, HIV diagnosis using classical algorithms in untreated HAT patients should be avoided. Specific, validated combinations of 3 HIV rapid tests can increase specificity.

[Immigration and HIV Infection. An approximation to parasitic and viral infections]

Highly-active antiretroviral therapy is effective in reducing opportunistic infections in industrialized countries. However, opportunistic parasitic infections remain the leading cause of HIV-related mortality in developing countries. These infections can also affect HIV-positive immigrants residing in Spain, as well as HIV-infected patients traveling to low-income countries. In addition, immigrants often have viral infections caused by herpesvirus, papillomavirus and polyomavirus, which are closely related to risk behaviors and commercial sex. The present article reviews the characteristics of parasitic and viral infections in patients with HIV infection with the aim of improving understanding of this vulnerable population group.

Immunology and immunopathology of African trypanosomiasis

Major modifications of immune system have been observed in African trypanosomiasis. These immune reactions do not lead to protection and are also involved in immunopathology disorders. The major surface component (variable surface glycoprotein,VSG) is associated with escape to immune reactions, cytokine network dysfunctions and autoantibody production. Most of our knowledge result from experimental trypanosomiasis. Innate resistance elements have been characterised. In infected mice, VSG preferentially stimulates a Th 1-cell subset. A response of <FONT FACE=Symbol>gd</FONT> and CD8 T cells to trypanosome antigens was observed in trypanotolerant cattle. An increase in CD5 B cells, responsible for most serum IgM and production of autoantibodies has been noted in infected cattle. Macrophages play important roles in trypanosomiasis, in synergy with antibodies (phagocytosis) and by secreting various molecules (radicals, cytokines, prostaglandins,...). Trypanosomes are highly sensitive to TNF-alpha, reactive oxygen and nitrogen intermediates. TNF-alpha is also involved in cachexia. IFN-gamma acts as a parasite growth factor. These various elements contribute to immunosuppression. Trypanosomes have learnt to use immune mechanisms to its own profit. Recent data show the importance of alternative macrophage activation, including arginase induction. L-ornithine produced by host arginase is essential to parasite growth. All these data reflect the deep insight into the immune system realised by trypanosomes and might suggest interference therapeutic approaches.

Parasitic central nervous system infections in immunocompromised hosts: malaria, microsporidiosis, leishmaniasis, and African trypanosomiasis

Immunosuppression associated with HIV infection or following transplantation increases susceptibility to central nervous system (CNS) infections. Because of increasing international travel, parasites that were previously limited to tropical regions pose an increasing infectious threat to populations at risk for acquiring opportunistic infection, especially people with HIV infection or individuals who have received a solid organ or bone marrow transplant. Although long-term immunosuppression caused by medications such as prednisone likely also increases the risk for acquiring infection and for developing CNS manifestations, little published information is available to support this hypothesis. In an earlier article published in Clinical Infectious Diseases, we described the neurologic manifestations of some of the more common parasitic CNS infections. This review will discuss the presentation, diagnosis, and treatment of the following additional parasitic CNS infections: malaria, microsporidiosis, leishmaniasis, and African trypanosomiasis.

The impact of HIV infection on tropical diseases

HIV and tropical infections affect each other mutually. HIV infection may alter the natural history of tropical infectious diseases, impede rapid diagnosis, or reduce the efficacy of antiparasitic treatment. Tropical infections may facilitate the transmission of HIV and accelerate progression from asymptomatic HIV infection to AIDS. This article reviews data on known interactions for malaria, leishmaniasis, human African trypanosomiasis, Chagas' disease, schistosomiasis, onchocerciasis, lymphatic filariasis, and intestinal helminthiases.

Options for field diagnosis of human african trypanosomiasis

Human African trypanosomiasis (HAT) due to Trypanosoma brucei gambiense or T. b. rhodesiense remains highly prevalent in several rural areas of sub-Saharan Africa and is lethal if left untreated. Therefore, accurate tools are absolutely required for field diagnosis. For T. b. gambiense HAT, highly sensitive tests are available for serological screening but the sensitivity of parasitological confirmatory tests remains insufficient and needs to be improved. Screening for T. b. rhodesiense infection still relies on clinical features in the absence of serological tests available for field use. Ongoing research is opening perspectives for a new generation of field diagnostics. Also essential for both forms of HAT is accurate determination of the disease stage because of the high toxicity of melarsoprol, the drug most widely used during the neurological stage of the illness. Recent studies have confirmed the high accuracy of raised immunoglobulin M levels in the cerebrospinal fluid for the staging of T. b. gambiense HAT, and a promising simple assay (LATEX/IgM) is being tested in the field. Apart from the urgent need for better tools for the field diagnosis of this neglected disease, improved access to diagnosis and treatment for the population at risk remains the greatest challenge for the coming years.

HIV infection and tropical parasitic diseases - deleterious interactions in both directions?

HIV and parasitic infections interact and affect each other mutually. Whereas HIV infection may alter the natural history of parasitic diseases, impede rapid diagnosis or reduce the efficacy of antiparasitic treatment, parasitoses may facilitate the infection with HIV as well as the progression from asymptomatic infection to AIDS. We review data on known interactions for malaria, leishmaniasis, Human African Trypanosomiasis, Chagas' disease, onchocerciasis, lymphatic filariasis, schistosomiasis and intestinal helminthiases. The common immunopathogenetic basis for the deleterious effects parasitic diseases may have on the natural history of HIV infection seems to be a particular type of chronic immune activation and a preferential activation of the T helper (Th)2 type of help. Control of parasitic diseases should complement the tools currently used in combating the HIV pandemic.

Leishmania, Trypanosoma and monoxenous trypanosomatids as emerging opportunistic agents

Immunosuppression is associated with the occurrence of a large variety of infections, several of them due to opportunistic protozoa. The parasitic protozoa of the family Trypanosomatidae vary greatly in their importance as potential opportunistic pathogens. African trypanosomiasis is no more common nor severe during AIDS. The situation with Chagas' disease, however, is much different. Although the process is not clearly understood, there appears to be a reactivation of Trypanosoma cruzi infection, which can lead to severe meningoencephalitis. In persons with AIDS, leishmaniasis is often exacerbated, particularly Leishmania infantum, which causes visceral leishmaniasis in southern Europe. Since 1990, 1,616 cases of visceral leishmaniasis/HIV co-infection have been reported, mainly from southern Europe, and particularly from Spain, southern France, and Italy. The co-infected patients are primarily young adults and belong to the risk group of intravenous drug users. Isoenzymatic identification of 272 isolates showed 18 different L. infantum zymodemes, of which 10 represent new zymodemes hitherto found only during HIV co-infection. New foci of co-infection are emerging in various parts of the world, including Brazil and East Africa. Moreover, since 1995, non-human monoxenous trypanosomatids have been found in AIDS patients, causing both diffuse cutaneous lesions and visceral infections. In countries where visceral leishmaniasis is endemic, particularly in southern Europe, immunosuppressive treatments for organ transplants or malignant diseases often result either in reactivation of asymptomatic visceral leishmaniasis or in facilitation of new infections.

The ethnic minority traveler

Although the ethnic minority traveler is exposed to the same risks as other travelers, there are special considerations that make them vulnerable to certain diseases. In addition, many ethnic minority travelers are traditionally underserved by the medical community and often travel without the benefit of adequate counseling and immunization. The specific disease entities covered in this article include parasitic diseases (e.g. malaria, trypanosomiasis, intestinal helminths), tuberculosis, and other respiratory diseases, dengue, and sexually transmitted diseases and HIV.

The compromised traveler

Compromised travelers represent a diverse and challenging group of individuals. They include HIV-infected patients who are at risk for potentially adverse reactions to immunizations, and new exposures to enteric water-borne opportunistic pathogens associated with chronic infections. Such travelers may encounter unfamiliar opportunistic fungi and classical tropical infections, such as leishmaniasis, whose pathogenesis can be enhanced by the presence of prior HIV infection. Other immunocompromised groups include those who are functionally or anatomically asplenic, and patients who are iatrogenically immunosuppressed from medications utilized for solid organ transplantation, chemotherapy, or treatment of malignancies. This population of travelers also includes those with diabetes mellitus who may require adjustments in their dosing, administration, and possibly even the types of insulin used on their trips. These patients are also at greater risk for acquisition of tuberculosis, severe community-acquired pneumonia, urinary tract infections, and pyomyositis. Older travelers present both the infectious disease and travel medicine specialist with issues such events, malignancy-related infections, myocardial infarction, and other forms of cardiopulmonary compromise, which the authors address in this article.

Adult Travelers with HIV Infection

The number of HIV-infected persons who travel to the developing world is increasing. Pleasure, business, other work, and illness or death in families brings these special travelers to all corners of the world.1,2 Health care providers should ask patients who are seeking advice whether they are HIV-infected or at risk so that these travelers can be adequately protected and prepared. In most instances international travel is feasible, but in some cases itineraries may be modified or additional recommendations may be given to make trips safer and more enjoyable. This paper reviews the health problems that persons with HIV infection may face during international travel, and their prevention.