Frequent Opportunistic Infection Research Articles

Seroprevalence of and Risk Factors for Cytomegalovirus among HIV-Infected Patients at University of Maiduguri Teaching Hospital, Nigeria

Although the distribution of cytomegalovirus (CMV) infection has a wide regional variation, it is more common in Africa and Asia with high prevalence approaching 100% in some communities. CMV is a frequent opportunistic infection and major cause of morbidity and mortality among HIV patients with severe immunosuppression. It can be contracted from body fluid, including saliva, urine, blood, cervical secretions, and semen. CMV seropositivity is considered the best laboratory measure of past infection. We determined the prevalence of CMV and the risk factors associated with its acquisition in a population of HIV positive patients. Anti-CMV IgG seroprevalence was 100% among HIV infected subjects and 98.6% among controls. Having multiple sexual partners and traditional practices were identified as risk factors associated with risk of contracting CMV infection.

Spatial distribution of the human development index, HIV infection and AIDS-Tuberculosis comorbidity: Brazil, 1982-2007.

AIDS epidemic has given visibility to the incidence of tuberculosis, for being the most frequent opportunistic infection. It is known that individuals who are socially vulnerable are more susceptible to HIV transmission and tuberculosis as well. This study aims to conduct a geoepidemiological study on HIV/AIDS, AIDS-Tuberculosis co-infection and social vulnerability. This is an ecological study using incidence rates and the human development index to produce thematic maps and a descriptive analysis of epidemiology. The records of reported cases of HIV/AIDS from 1982 to 2007 were used, considering as cases of AIDS-Tuberculosis those records that were positively diagnosed with tuberculosis and those records with unknown diagnosis of tuberculosis, but showing compatible signs and symptoms with tuberculosis (fever, cough, cachexia and asthenia). The maps allowed the identification of areas with social differences and different patterns of incidence of HIV/AIDS and AIDS-Tuberculosis; regional differences were similar to those found by Josué de Castro, in 1940; regions with higher human development index values also showed higher incidence HIV/AIDS and AIDS-Tuberculosis. The prevention of HIV infection must be geographically specific, given socioeconomic and cultural differences. Although official records show decline in AIDS-TB co-infection, treatment of cases of HIV/AIDS should observe the occurrence of opportunistic diseases, which should be notified and/or updated.

Cryptococcose disséminée et sarcoïdose pulmonaire : une association fortuite ?

We report a case of cryptococcal infection that underwent in a patient with a medical history of asymptomatic sarcoidosis. This finding seems to be not incidental. A 35-years-old female was referred to hospital for a community-acquired pneumonia with pleural involvement. A physical examination showed a pleural syndrome. Chest imaging showed a parenchymal involvement with pleural effusion and numerous mediastinal nodes. Fiberoptic bronchoscopy revealed an obstruction of the right apical bronchus of the lower lobe. Biopsies and bronchoalveolar lavage confirmed a cryptococcal infection. The disease was considered as disseminated with a urinary and neurologic involvement. The outcome was fair under prolonged antifungal therapy. Cryptococcal infection is generally associated with immunosuppression. We suggest that sarcoidosis, although non symptomatic, may be a condition that promote the onset of cryptococcal infection. Even rare, cryptococcal infection is the most frequent opportunistic infection recorded with sarcoidosis patients. Histologic similarities between sarcoidosis and cryptococcal infection and the role of the macrophages which phagocyte the Cryptococcus neoformans are one of the hypothesis to assess these pathologic findings. A register is warranted to recover all opportunistic infection related to sarcoidosis in order to better understand the pathogeny.

Disseminated Histoplasmosis and CMV Colitides Coinfection in AIDS

Purpose: The number of immunocompromised patients continues to grow, with improved screening and treatment of HIV, as well as the increasing use of immunosuppressive medications. Such patients are at increased risks for developing GI opportunistic infections. Even though cytomegalovirus (CMV) remains one of the most common opportunistic infection, patients may have coinfections with other rare, opportunistic fungal infections that may be associated with high mortality. We present a rare case of disseminated Histoplasmosis and CMV coinfection in an AIDS patient. A 41-year-old Hispanic male with history of AIDS and recently started on HAART therapy now presents with progressive, persistent diarrhea. He reports between 8-10 non-bloody, watery bowel movements daily, associated with a 20-pounds weight loss, intermittent night sweats, and subjective fevers. On physical exam, the patient had low-grade fever with mild hypotension. He was non-toxic appearing, with evidence of epigastric tenderness with mild voluntary guarding, but no rebound tenderness. On laboratory review, his white count was 3,400, CD4 count of 31, and an alkaline phosphatase of 190, but otherwise normal liver function tests. His blood cultures, stool cultures, ova, parasites, and Clostridium difficile were negative. The patient's abdominal computed tomography showed mild thickening of the small bowel and colon, with moderate mesenteric adenopathy. His upper endoscopy showed severe candidal esophagitis in the entire esophagus, non-erosive gastritis, and duodenitis, with multiple biopsies showing evidence of many yeast organisms present on GMS and PAS stains without evidence of mycobacterium present on AFB stain. His colonoscopy showed severe left-sided colitis with ulcerating, edematous, and erythematous mucosa, with multiple biopsies and viral and fungal cultures positive for histoplasmosis, CMV via PCR, as well as demonstrating aggregates of histiocytes in the lamina propria, granulomas, and chronic active colitis. His serology was consistently positive for histoplasmosis, but negative for giardia, cryptosporidium, cyclospora, and microsporidia. The patient was subsequently treated for combined histoplasmosis, CMV, and esophageal candidiasis with marked symptom and biochemical improvement, and he continues to be on antifungal therapy for one-year for disseminated histoplasmosis. Our case highlights the importance of screening for coinfections in immunocompromised patients involving CMV, but also less frequent opportunistic infections, like histoplasmosis, that can be associated with high mortality.

Increased susceptibility for aspergillosis and post‐transplant immune deficiency in patients with gene variants of TLR4 after stem cell transplantation

Toll-like receptors (TLRs) detect invading pathogens through several pattern-recognition mechanisms and play a central role in the regulation of the immune system. In allogeneic hematopoietic stem cell transplantation (HSCT), the frequent opportunistic fungal infections remain an important cause of mortality and morbidity in these highly immunocompromised patients. We analyzed 154 patients after allogeneic HSCT for acute leukemia for TLR4 gene variants 1063A/G (D299G) and 1363C/T (T399I) with their respective donors, and correlated the results with the incidence of invasive aspergillosis (IA) infection after transplant. Probable and proven IA in recipients was significantly increased if either recipients or donors exhibited one of the two TLR4 gene variants. In addition, recipients with TLR gene variants and IA showed a delayed T cell and NKT cell immune reconstitution after transplant. Increased susceptibility for IA was not associated with an increased rate of death-in-remission or decreased estimate for overall survival. These findings reinforce the importance of genetic variants in innate immunity and IA among the recipients of allogeneic HSCT.

Common Infectious Diseases in HIV Infected Persons

Opportunistic infections (OIs) are defined as infections that are more frequent or more severe because of immunosuppression in HIV-infected persons. Before the widespread use of combination antiretroviral therapy (ART), OIs were the major cause of morbidity and mortality of HIV-infected persons. Although hospitalizations and deaths have decreased since the implementation of ART, OIs remain a leading cause of morbidity and mortality in HIV-infected persons. The frequent OIs in HIV-infected persons are tuberculosis, Pneumocystis pneumonia, candidiasis, Cytomegalovirus infection, toxoplasmosis, cryptococcosis, and so on. The aim of the present review is to provide a brief introduction on clinical features, diagnosis and treatment of common OIs in HIV-infected persons. (Korean J Med 2013;84:179-185)

Lung transplant infection

ABSTRACTLung transplantation has become an accepted therapeutic procedure for the treatment of end‐stage pulmonary parenchymal and vascular disease. Despite improved survival rates over the decades, lung transplant recipients have lower survival rates than other solid organ transplant recipients. The morbidity and mortality following lung transplantation is largely due to infection‐ and rejection‐related complications. This article will review the common infections that develop in the lung transplant recipient, including the general risk factors for infection in this population, and the most frequent bacterial, viral, fungal and other less frequent opportunistic infections. The epidemiology, diagnosis, prophylaxis, treatment and outcomes for the different microbial pathogens will be reviewed. The effects of infection on lung transplant rejection will also be discussed.

Prevalence and Risk Factors of Esophageal Candidiasis in Healthy Individuals: A Single Center Experience in Korea

PurposeEsophageal candidiasis (EC) is the most frequent opportunistic fungal infection in immunocompromised host. However, we have found EC in healthy individuals through esophagogastroduodenoscopy (EGD). The aim of this study was to determine the prevalence and risk factors for EC in healthy individuals.Materials and MethodsWe retrospectively reviewed the medical records of 281 patients who had been incidentally diagnosed with EC. We also conducted age and sex matched case control study to identify the risk factor for EC.ResultsThe prevalence of EC was 0.32% (281/88125). The most common coexisting EGD finding was reflux esophagitis (49/281, 17.4%). An antifungal agent was prescribed in about half of EC, 139 cases (49.5%). Follow-up EGD was undertaken in 83 cases (29.5%) and 20 cases of candidiasis was persistently found. Case control study revealed EC were more often found in user of antibiotics (p=0.015), corticosteroids (p=0.002) and herb medication (p=0.006) as well as heavy drinking (p<0.001).ConclusionThe prevalence of EC was 0.32% (281/88125) in Korea. Use of antibiotics, corticosteroids and herb as well as heavy drinking were significant risk factors for EC in healthy individuals.

An unsuspected case of cerebral toxoplasmosis: case report and literature review

Toxoplasmosis caused by Toxoplasma gondii is one the most frequent opportunistic infections among the immunocompromised patients and commonly affects the brain of those individuals with advanced human immunodeficiency virus (HIV) infection with acquired immune deficiency syndrome (AIDS). Cerebral toxoplas-mosis can be a challenging histopathological diagnosis when it presents as the early sequela of clinically unsuspected immuno-suppression. We report a case with problematic histopathological diagnosis of cerebral toxoplasmosis because of the patient’s unsuspected HIV status, the clinico-radiological impression of metastatic malignancy, and the compounded difficulty of identifying the typical T. gondii organisms in frozen section material. However, this case highlights the need to always contemplate a non-neoplastic infective cause as the basis for observed necrosis in brain biopsies, regardless of the clinical suspicion under which the histopatholo-gical examination has been requested.

Genetic Diversity and Genomic Plasticity ofCryptococcus neoformansAD Hybrid Strains

Natural hybridization between two strains, varieties, or species is a common phenomenon in both plants and animals. Although hybridization may skew established gene pools, it generates population diversity efficiently and sometimes results in the emergence of newly adapted genotypes. Cryptococcus neoformans, which causes the most frequent opportunistic fungal infection in immunocompromised hosts, has three serotypes: A, D, and AD. Serotype-specific multilocus sequence typing and serotype-specific comparative genome hybridization were applied to investigate the genetic variability and genomic organization of C. neoformans serotype AD isolates. We confirm that C. neoformans serotype AD isolates are hybrids of serotype A and D strains. Compared with haploid strains, most AD hybrid isolates exhibit unique multilocus sequence typing genotypes, suggesting that multiple independent hybridization events punctuated the origin and evolutionary trajectory of AD hybrids. The MATa alleles from both haploid and AD hybrid isolates group closely to form a cluster or subcluster in both the serotype A and D populations. The rare and unique distribution of MATa alleles may restrict sexual reproduction between isolates of opposite mating types. The genetic diversity of the serotype D population, including haploid strains and serotype D genomes of the AD hybrid, is significantly greater than that of serotype A, and there are signatures of recombination within the serotype D population. Given that MATa isolates are relatively rare, both opposite-sex and same-sex mating may contribute to genetic recombination of serotype D in nature. Extensive chromosome loss was observed in AD hybrid isolates, which results in loss of heterozygosity in the otherwise-heterozygous AD hybrid genome. Most AD hybrid isolates exhibit hybrid vigor and are resistant to the antifungal drug FK506. In addition, the C. neoformans AD hybrid genome is highly dynamic, with continuous chromosome loss, which may be a facile route for pathogen evolution through which genotypic and phenotypic variation is generated.

Development of a Splenic Marginal Zone Lymphoma Associated with Active Chronic Visceral Leishmaniasis

Abstract 5202We here report the observation of the development of a splenic marginal zone lymphoma (SMZL) after years of active chronic visceral Leishmania (VL) infection, implying a possible pathogenic link between these two conditions, where the neoplastic process is preceded by a prolonged period of chronic antigen stimulation.In 2004, a 60-year old male developed attack-like episodes of septic fever with chills, rigor and subsequent profound fatigue. He had a 4 years previous medical history of severe asthma-like symptoms and hypereosinophilia. A bone marrow (BM) and liver biopsy were inconclusive. A whole-body computed tomography showed a moderately enlarged spleen. No evidence of bacterial, fungal or viral infection was found; the symptoms persisted, although mitigated, with occasional exacerbations over the following 3 years.By 2007 the patient was admitted again and a new BM biopsy was taken, still showing reactive changes. Due to increased splenomegaly, a diagnostic splenectomy was performed. Examination of the spleen revealed a primary splenic marginal zone lymphoma (SMZL).In 2010 the patient was admitted with septicaemia and constitutional symptoms. A BM biopsy showed the presence of numerous Leishmania amastigotes and a retrospective review of all previous biopsies (since 2004) identified Leishmania amastigotes in all of them.In fact, a thorough travel history covering the previous two decades revealed several visits, often twice a year, to the Mediterranean basin, e.g. Greece and Malta, areas endemic for Leishmania infantum (L. infantum).Visceral Leishmaniasis is a frequent opportunistic infection in HIV-infected immunodeficient individuals but uncommon in cancer patients, and only a few cases of VL in patients with already well-established malignant lymphoma have been reported.Chronic antigenic stimulation by microbial pathogens has been proposed as a pathogenetic factor in a variety of marginal zone lymphomas. Tissue specific immune responses toward Leishmania parasites have been shown in rodents, and the spleen is a ‘safe harbor' for the long-term persistence of visceralizing Leishmania. Sustained antigenic stimulation with upregulation of critical signaling pathways may result in prolonged polyclonal B-cell proliferation, and a subsequent increased risk of malignant transformation.This case is the first to provide evidence for a possible link between chronic antigen stimulation by long-lasting L. infantum infection and the development of a SMZL. Disclosures:No relevant conflicts of interest to declare.

Candida in oral pre-cancer and oral cancer

Oral pre-malignancies and carcinomas are common epithelial pathologies caused by a variety of etiological factors. In the oral cavity, candidiasis is the most frequent opportunistic fungal infection. Since the initial reports of an association between candidiasis with oral pre-cancer and cancer, various theories have been debated regarding the role of candida in development and transformation of oral pre-malignancies. However, the exact role is still unclear. In the present article, we hypothesize a causal role for candidiasis in oral pre-cancer and cancer albeit an indirect one. We also suggest that candida along with other co-factors may play a role in initiation and promotion of carcinogenesis.

Increased expression of virulence attributes in oral Candida albicans isolates from human immunodeficiency virus-positive individuals

Oral candidiasis caused by Candida albicans is recognized as one of the most frequent opportunistic infections in human immunodeficiency virus (HIV)-infected individuals. The overall severity and chronicity of oral candidiasis has been attributed exclusively to the HIV-induced immune deficiency of the affected individuals but not to the virulence factors of the pathogen, i.e. C. albicans. However, genotypic and phenotypic studies have suggested that HIV infection might be associated with preferential selection of C. albicans strains with altered virulence determinants, leading to colonization with Candida populations that are better able to cause disease in these immunologically compromised hosts. If this process of selection is indeed related to pathogenicity, it may be possible to measure alterations in different virulence factors produced by C. albicans in HIV-infected patients. To evaluate this hypothesis, the present work was undertaken to determine simultaneously the expression of five virulence factors in oral C. albicans isolates colonizing and infecting HIV-positive and -negative individuals. The significance of genotypes in the pathogenesis of oral candidiasis was also elucidated. Oral swabs were collected from 335 consecutive individuals (210 HIV-positive and 125 HIV-negative). Virulence factors and genotypes were determined for all the C. albicans strains isolated. The results showed significantly increased expression of proteinase, phospholipase and haemolytic activities, as well as a greater ability to adhere, in isolates from HIV-positive compared with HIV-negative individuals (P<0.05). However, no significant differences in virulence factor expression in isolates colonizing or infecting HIV-positive individuals were seen. Genotype A was the predominant type (71.3 %); however, a relationship could not be established between the genotypes and the virulence factors, or with clinical infection. These data support the concept of preferential C. albicans strain selection with altered virulence determinants in HIV-infected individuals and emphasize the need for further molecular genetic linkage studies that could be helpful in dissecting the molecular causes of preferential strain selection, which may lead to new approaches for therapeutic intervention.

Seroprevalence of Toxoplasma gondii IgG antibody in HIV-infected patients at the Lagos University Teaching Hospital.

BackgroundToxoplasmosis is caused by infection with a ubiquitous intracellular protozoan parasite, Toxoplasma gondii. With the advent of the HIV pandemic in Nigeria, toxoplasmic encephalitis has become one of the more frequent opportunistic infections and the most commonly implicated cause of focal brain lesions complicating the course of AIDS.ObjectivesThis study was conducted to compare the pattern of seroprevalence of T. gondii (Toxo-IgG) antibodies among HIV-infected persons presenting with neurological complications and those without.Materials and methodsPlasma specimens collected from 380 subjects were tested for Toxo- IgG antibodies by enzyme immunoassay technique and CD4 estimation by flow cytometry. Close-ended questionnaires were applied to all respondents to collect relevant data, with ethical approval from the hospital ethical committee. Plasma was obtained from two study groups comprising 300 HIV-positive respondents without neurological presentations, and 80 HIV-positive respondents with neurological complications.ResultsSeroprevalence of Toxo-IgG antibodies was 58% in the HIV-positive study group without neurological complications (of these, 79.2% were males and 38.5% were females) and 40% in the study group with neurological complications (46.2% of these were males and 28.6% were females). The overall seroprevalence of Toxo-IgG antibodies among the HIV-positive respondents (with and without neurological complications) was 54.2% (206 of 380). Seroprevalence of Toxo-IgG antibodies was lowest among the educated subjects (19% of the respondents with tertiary education) and among females in both study groups. A higher proportion of the subjects with neurological complications had CD4 cell count <100 cells/μL compared with respondents without neurological defects (39% vs 22.7%; P = 0.000), but the seroprevalence of Toxo-IgG antibodies was higher in subjects without neurological complications (45% vs 31.3%; P = 0.000).ConclusionToxoplasmosis, though an important opportunistic infection in our environment, may not account for the majority of neurological complications observed in patients with HIV infection in our center.

Pneumocystis jiroveciipneumonia in developing countries

Pneumocystis pneumonia (PcP) is a serious fungal infection among immunocompromised patients. In developed countries, the epidemiology and clinical spectrum of PcP have been clearly defined and well documented. However, in most developing countries, relatively little is known about the prevalence of pneumocystosis. Several articles covering African, Asian and American countries were reviewed in the present study. PcP was identified as a frequent opportunistic infection in AIDS patients from different geographic regions. A trend to an increasing rate of PcP was apparent in developing countries from 2002 to 2010.

A Patient Presenting with Diffuse Cutaneous Leishmaniasis (DCL) as a First Indicator of HIV Infection in India

Opportunistic parasitic infections such as leishmaniasis are common in human immunodeficiency virus (HIV)-infected patients and are usually acquired several days after initial diagnosis of HIV infection. Here, we report on a patient who presented with diffuse cutaneous leishmaniasis (DCL) caused by Leishmania tropica as the first and only clinical manifestation of HIV infection. To the best of our knowledge, this is the first case that illustrates that DCL could be the first clinical indicator of HIV infection. Cutaneous leishmaniasis (CL) and DCL are becoming frequent opportunistic infections in HIV-infected individuals throughout the world. To date, all documented cases of CL and HIV coinfections have been reported in patients who were known cases of HIV and who subsequently developed CL. In this report, we present a case that illustrates that DCL could be the first clinical indicator of HIV infection.

Human cytomegalovirus infection and clinical status of infants born to human immunodeficiency virus type 1 infected mothers

Objective. Human cytomegalovirus (HCMV) is one of the most common congenital infections worldwide and a frequent opportunistic infection that aggravates the condition of human immunodeficiency virus (HIV)-infected patients. The aim of the study was to evaluate the frequency and factors influencing HCMV infection among infants of HIV-positive women.Methods. The study included 35 infants born to HIV-1-infected mothers examined for congenital infections. Children were evaluated for human immunodeficiency virus type 1 (HIV-1), HCMV, and HCV infection by serological and molecular methods.Results. HIV-1 infection was found in one child whose mother did not receive antiretroviral treatment during pregnancy, and HCV infection in another infant. HCMV-DNA in the urine was present in 13/35 infants (37.14%) on the 10th day and 24/35 infants (68.57%) in the 4th week of life. The majority of HCMV-infected infants were asymptomatic, although they manifested microcephaly and low birth weight significantly more frequently (p = 0.006 and p = 0.02, respectively). Type HIV prophylaxis did not influence HCMV transmission.Conclusions. Although often asymptomatic, HCMV infection in infants born to HIV-infected mothers is frequent and may be associated with prematurity, low birth weight, and microcephaly. Diagnostic procedures in children of HIV-infected mothers should involve HCMV.

What Is AIDS in the Amazon and the Guianas? Establishing the Burden of Disseminated Histoplasmosis

The pathogen ecology of Amazonian regions may lead to specific differences in the most frequent clinical presentations of acquired immunodeficiency syndrome (AIDS). A retrospective cohort study was thus conducted to describe the main AIDS-defining events in French Guiana. Disseminated histoplasmosis was the most frequent opportunistic infection (15.4/1000 person years).

Acute cytomegalovirus pneumonia and hepatitis presenting during acute HIV retroviral syndrome

Cytomegalovirus (CMV) disease is a frequent opportunistic infection that usually occurs in the late stages of HIV infection as a result of reactivation of a latent infection. We report a case of a 23-year-old man with acute retroviral syndrome complicated by coexisting CMV pneumonia and CMV hepatitis, which were documented by histopathological examination. His CMV pneumonia and hepatitis were assumed to be primary CMV diseases owing to the absence of CMV IgG antibody. To the best of our knowledge, this is the first case of simultaneous CMV pneumonia and hepatitis occurring as primary CMV diseases during primary HIV infection. This case indicates that invasive CMV diseases such as pneumonia and hepatitis should be considered even in patients with primary HIV infection.

Human Immunodeficiency Virus-Associated Tuberculosis

Human Immunodeficiency Virus-Associated Tuberculosis