Toxoplasmosis of spinal cord in acquired immunodeficiency syndrome patient presenting as paraparesis: a rare entity

Anti-Toxoplasma gondii activity of rose hip oil-solid lipid nanoparticles

Toxoplasma gondii is a highly prevalent pathogen, reported from almost all geographical regions of the world. Current anti-T. gondii drugs are not effective enough in immunocompromised patients, encephalitis, chorioretinitis, and congenital toxoplasmosis. Therefore, the prescription of these drugs has been limited. Rose hip oil (RhO) is a natural plant compound, which shows antibacterial, anticancer, and anti-inflammatory activities. In the current study, the anti-T. gondii and cell toxicity effects of solid lipid nanoparticles (SLNs) loaded by RhO (RhO-SLNs) were evaluated. Emulsification sonicated-homogenization method was used to prepare SLNs. RhO-SLNs were characterized, and their anti-T. gondii and cell toxicity effects were evaluated using in vitro analyses. The particle size and the zeta potential of the nanoparticles were 152.09 nm and -15.3 mV nm, respectively. The entrapment efficiency percentage was 79.1%. In the present study, the inhibitory concentration (IC)50 against T. gondii was >1 μg/mL (p-value <.0001). The cell toxicity assay showed cytotoxicity concentration (CC)50 >10 mg/mL (p-value = .017). In addition, at least 75% of T. gondii-infected Vero cells remained alive at concentrations >10 mg/mL. The concentration of 1 mg/mL showed highest anti-Toxoplasma activity and lowest cell toxicity against the Vero cell. Our findings suggest that carrying natural plant compounds with SLNs could be considered an effective option for treatment strategies against T. gondii infections.

Seroprevalence of Anti-Toxoplasma gondii Antibodies among Patients with Cancer at Hiwa Cancer Hospital in Sulaimani City, Kurdistan Region, Iraq

Background

Toxoplasma gondii is an opportunistic protozoan parasite that causes a life-threatening disease - toxoplasmosis - in immunocompromised individuals, including patients with cancer. This prospective cross-sectional study set out to determine the prevalence of toxoplasmosis in patients with cancer compared with that of healthy individuals.

Methods

A prospective cross-sectional study was conducted in Sulaimani City of Iraq from November 2019 to May 2020. Anti-T. gondii IgG and IgM antibodies were measured in the blood samples of 113 patients with cancer (80 with solid organ tumors and 33 with haematological malignancies) entered to Hiwa Cancer Hospital and 82 healthy controls, who were referred to the Directorate of Blood Transfusion for blood donation, using chemiluminescence microparticle immunoassay (CMIA).

Results

The prevalence of anti-T. gondii IgG was 39.8% in the patient group and 24.4% in the control group, which amounted to a significant difference (P = 0.024). Only one case of anti-T. gondii IgM positivity was observed in the patient group, and no IgM seropositivity was reported in the control group. Moreover, the seroprevalence of anti-T. gondii IgG was non-significantly higher (P = 0.102) in the patients with haematological malignancies (51.5%) than in those with solid organ tumors (35%). Occupation was the only risk factor which had a significant association with T gondii infection (odds ratio [OR]: 1.3, 95% confidence interval [CI]: 0.6746163 - 2.4282788, P = 0.029).

Conclusion

The prevalence of T. gondii infection is higher in patients with cancer than in healthy individuals. Therefore, T. gondii screening in patients with cancer is recommended.

Troublemaking Lesions: Spinal Tumor Mimics

There are various mass-like lesions that can mimic true neoplasms in the spine, including inflammatory, infectious, vascular, congenital, and degenerative etiologies. While some lesions have distinctive imaging features that suggest a correct diagnosis, others have overlapping characteristics that do not allow their differentiation based solely on their imaging findings. For entities with nonspecific imaging features, knowledge of the clinical and laboratory information is critical to provide an accurate diagnosis.

Adverse pregnancy outcomes in Toxoplasma gondii seropositive Hispanic women

AIMS

Chronic Toxoplasma gondii infection is not thought to affect pregnancy or birth outcomes, but there are few prospective studies. The study aims were T. gondii immunoglobulin G measurement and relationship of chronic T. gondii infection with gestational age at birth and adverse pregnancy outcomes in 690 Hispanic women in Tampa, Florida.

METHODS

Hispanic women, born either in the United States or in Latin America or the Caribbean had a venous blood sample drawn to measure T. gondii IgG and T. gondii serotype at the first prenatal visit, along with collection of demographic and health-related measures. Seropositive and seronegative women were followed throughout their pregnancy. Gestational age, infant weights, and adverse pregnancy outcomes (miscarriages, preterm births) were compared in the two groups.

RESULTS

There were 740 women of self-reported Hispanic ethnicity screened and enrolled in Tampa, Florida, with 690 having birth data extracted from the electronic health record (538 T. gondii negative and 152 T. gondii seropositive). T. gondii seropositivity was 22.4% and the majority (83%) had high avidity titers, indicating chronic infection. Compared to T. gondii seronegative Hispanic women, seroseropositive women had more smaller for gestational age infants and higher prevalences of miscarriages and preterm birth.

CONCLUSION

This is one of the largest longitudinal cohort studies of women with chronic T. gondii infection followed through pregnancy. There was a higher percentages of adverse pregnancy outcomes in this group compared to T. gondii seronegative controls. The mechanism for this is unknown and warrants reexamination of the dogma that chronic T. gondii infection in pregnant women has no significant clinical consequences.

Prevalence of Toxoplasma gondii in HIV-Infected Individuals in Iran: A Systematic Review and Meta-Analysis

INTRODUCTION

Toxoplasma gondii is an obligate intracellular protozoan that can infect almost all warm-blooded animals, including humans. Patients with co-infection with toxoplasmosis and HIV have a 30-40% risk of developing toxoplasmosis encephalitis. This study aimed to describe the epidemiology and burden of Toxoplasma gondii in HIV-infected individuals in Iran.

METHODS

We searched the five English databases (Science Direct, PubMed, Scopus, Ovid, Embase, and Cochrane) and four Persian databases (Scientific Information Database (SID), Iran Medex, Iran Doc, and Magiran) with the terms of (Toxoplasma gondii OR "toxoplasmosis") AND (HIV OR "AIDS" OR immunodeficiency OR acquired immune deficiency syndrome) AND (Seroprevalence) AND (Seroepidemiologic Studies) AND (Elisa OR IgG) AND (PCR) AND (Iran) by two authors up to Feb 2021. Studies were included if they investigated people with HIV infection and presented data that allowed us to establish the prevalence of Toxoplasma gondii infection in Iran.

RESULTS

According to the inclusion/exclusion criteria, 15 studies were selected. A total number of 2275 HIV-infected individuals were tested and evaluated for toxoplasmosis from 2005 up to 2018 in different regions of Iran. The weighted overall prevalence of toxoplasmosis in HIV-infected individuals with Elisa was obtained using a random-effects model, which was estimated at 47% (95% CI = 31% - 62%). Also, the Weighted overall prevalence of toxoplasmosis in HIV-infected individuals with PCR was obtained using a random-effects model, which was estimated at 7% (95% CI = 3% - 12%).

CONCLUSION

According to the results of this study, it can be clearly understood that a large population of HIV patients living in Iran have toxoplasmosis. Therefore, due to the high susceptibility of these groups to toxoplasmosis, healthcare professionals must consider measures such as training in the ways of transmission and prevention of the infection to this high-risk group in order to reduce the risk of infection.

Inhibition of Toxoplasma gondii by 1,2,4-triazole-based compounds: marked improvement in selectivity relative to the standard therapy pyrimethamine and sulfadiazine

A safer treatment for toxoplasmosis would be achieved by improving the selectivity profile of novel chemotherapeutics compared to the standard therapy pyrimethamine (PYR) and sulfadiazine (SDZ). We previously reported on the identification of the compounds with imidazole-thiosemicarbazide scaffold as potent and selective anti-Toxoplasma gondii (T. gondii) agents. In our current research, we report on the optimisation of this chemical scaffold leading to the discovery cyclic analogue 20 b with s-triazole core structure. This compound displayed prominent CC₃₀ to IC₅₀ selectivity index (SI) of 70.72, making it 160-fold more selective than SDZ, 11-fold more selective than PYR, and 4-fold more selective than trimethoprim (TRI). Additionally, this compound possesses prerequisite drug-like anti-Toxoplasma properties to advance into preclinical development; it showed ability to cross the BBB, did not induce genotoxic and haemolytic changes in human cells, and as well as it was characterised by low cellular toxicity.

Protozoan co-infections and parasite influence on the efficacy of vaccines against bacterial and viral pathogens

A wide range of protozoan pathogens either transmitted by vectors (Plasmodium, Babesia, Leishmania and Trypanosoma), by contaminated food or water (Entamoeba and Giardia), or by sexual contact (Trichomonas) invade various organs in the body and cause prominent human diseases, such as malaria, babesiosis, leishmaniasis, trypanosomiasis, diarrhea, and trichomoniasis. Humans are frequently exposed to multiple pathogens simultaneously, or sequentially in the high-incidence regions to result in co-infections. Consequently, synergistic or antagonistic pathogenic effects could occur between microbes that also influences overall host responses and severity of diseases. The co-infecting organisms can also follow independent trajectory. In either case, co-infections change host and pathogen metabolic microenvironments, compromise the host immune status, and affect microbial pathogenicity to influence tissue colonization. Immunomodulation by protozoa often adversely affects cellular and humoral immune responses against co-infecting bacterial pathogens and promotes bacterial persistence, and result in more severe disease symptoms. Although co-infections by protozoa and viruses also occur in humans, extensive studies are not yet conducted probably because of limited animal model systems available that can be used for both groups of pathogens. Immunosuppressive effects of protozoan infections can also attenuate vaccines efficacy, weaken immunological memory development, and thus attenuate protection against co-infecting pathogens. Due to increasing occurrence of parasitic infections, roles of acute to chronic protozoan infection on immunological changes need extensive investigations to improve understanding of the mechanistic details of specific immune responses alteration. In fact, this phenomenon should be seriously considered as one cause of breakthrough infections after vaccination against both bacterial and viral pathogens, and for the emergence of drug-resistant bacterial strains. Such studies would facilitate development and implementation of effective vaccination and treatment regimens to prevent or significantly reduce breakthrough infections.

Attenuated Toxoplasma gondii enhances the antitumor efficacy of anti-PD1 antibody by altering the tumor microenvironment in a pancreatic cancer mouse model

PURPOSE

To investigate whether attenuated Toxoplasma is efficacious against solid tumors of pancreatic cancer and whether attenuated Toxoplasma improves the antitumor activity of αPD-1 antibody on pancreatic cancer.

METHODS

The therapeutic effects of attenuated Toxoplasma NRTUA strain monotherapy and combination therapy of NRTUA with anti-PD-1 antibody on PDAC tumor volume and tumor weight of Pan02 tumor-bearing mice were investigated. We characterized the effects of combination therapy of NRTUA with anti-PD-1 antibody on tumor-infiltrating lymphocytes and tumor-specific IFN-γ by using immunohistochemistry, flow cytometry and ELISA. The antitumor mechanisms of combination therapy of NRTUA with anti-PD-1 antibody were investigated via depletion of CD8+ T cells and IL-12.

RESULTS

NRTUA strain treatment inhibited tumor growth in a subcutaneous mouse model of PDAC through activating dendritic cells and increasing CD8+ T cell infiltration in the tumor microenvironment. More importantly, combination therapy of NRTUA with anti-PD-1 antibody elicited a significant antitumor immune response and synergistically controlled tumor growth in Pan02 tumor-bearing mice. Specifically, the combination treatment led to elevation of CD8+ T cell infiltration mediated by dendritic cell-secreted IL-12 and to tumor-specific IFN-γ production in the PDAC tumor microenvironment. Also, the combination treatment markedly reduced the immunosuppressive myeloid-derived suppressor cell population in PDAC mice.

CONCLUSION

These findings could provide a novel immunotherapy approach to treating solid tumors of PDAC and overcoming resistance to anti-PD-1 agents in PDAC tumors.

Ginger Is a Potential Therapeutic for Chronic Toxoplasmosis

Background:Toxoplasma gondii (T. gondii) is an opportunistic parasite that causes serious diseases in humans, particularly immunocompromised individuals and pregnant women. To date, there are limited numbers of therapeutics for chronic toxoplasmosis which necessitate the discovery of effective and safe therapeutics. In the present study, we aimed to evaluate the antitoxoplasmosis potential of ginger extract in mice with experimentally induced chronic toxoplasmosis. Results: Treatment with ginger extract significantly reduced cysts count in the brains of T. gondii-infected mice with a marked alleviation of edema and inflammation, and a reversal of neuronal injury. Moreover, ginger extract treatment reduced inflammation in liver and lungs and protected hepatocytes from infection-induced degeneration. Consistently, apoptosis was significantly mitigated in the brains of ginger extract-treated mice compared to infected untreated animals or spiramycin-treated animals. Methods: Four groups of Swiss albino mice (10 mice each) were used. The first group was not infected, whereas 3 groups were infected with Me49 T. gondii strains. One infected group remained untreated (infected untreated), whereas the other two infected groups were treated with either ginger extract (250 mg/kg) or spiramycin (positive control; 100 mg/kg), respectively. The therapeutic potential of ginger extract was evaluated by calculation of the parasite burden in infected animals, and examination of the infected tissues for reduced pathologic changes. Conclusions: Our results showed for the first time that ginger extract exhibited marked therapeutic effects in mice with chronic T. gondii infection which indicates that it can be used as a safe and effective treatment for chronic toxoplasmosis.

Seronegative Infection with Toxoplasma gondii in Asymptomatic Human Immunodeficiency Virus Type 1 (HIV-1)-Infected Patients and in Blood Donors

Background: Toxoplasmosis is a common opportunistic infection in AIDS patients. The routine diagnostics is based on serologic testing and IgG avidity index, but it may have limited utility in immunodeficient patients; thus, it is recommendable to detect T. gondii DNA in subjects with advanced HIV disease. The results of the studies published so far focused on patients with clinical symptoms of toxoplasmosis. Our study encompassed a group of HIV-infected subjects on cART therapy, without immunological disturbances and clinical symptoms of T. gondii infection. Methods: The study was retrospective, and samples were collected between 2013 and 2016. We evaluate the prevalence of serological (IgM, IgG, and avidity IgG) and molecular (DNA) T. gondii infection markers in asymptomatic HIV-infected patients and the control group using serologic (ELISA) and quantitative (real-time PCR) molecular testing. Results: Of 152 HIV-infected in routine follow-up tested for T. gondii IgM and IgG, 6 (3.9%) and 50 (32.9%) were positive, respectively. Of 168 serum samples from blood donors, 1 (0.6%) and 49 (29.2%) were IgM⁺ and IgG⁺ positive, respectively. IgM seroprevalence in HIV-infected patients was significantly higher than in blood donors. T. gondii DNA (genotype II) was identified in 47 (30.9%) HIV-infected patients, with 13 (8.6%) IgM⁻IgG⁻ samples. In blood donors, T. gondii DNA was present in 15 (8.9%) IgM⁻IgG⁻. Conclusions: In both groups, T. gondii DNA was detectable in seronegative subjects, implying the need to supplement the routine serological testing via the molecular method. It can help the accurate monitoring of the reactivation of infection in asymptomatic HIV-infected persons, and the quick introduction of specific therapy, in blood donors, would be of high importance for safe blood donations.

Parasitic infections of the spine: case series and review of the literature

OBJECTIVEAlthough parasitic infections are endemic to parts of the developing world and are more common in areas with developing economies and poor sanitary conditions, rare cases may occur in developed regions of the world.METHODSArticles eligible for the authors' literature review were initially searched using PubMed with the phrases "parasitic infections" and "spine." After the authors developed a list of parasites associated with spinal cord infections from the initial search, they expanded it to include individual diagnoses, using search terms including "neurocysticercosis," "schistosomiasis," "echinococcosis," and "toxoplasmosis."RESULTSTwo recent cases of parasitic spinal infections from the authors' institution are included.CONCLUSIONSKey findings on imaging modalities, laboratory studies suggestive of parasitic infection, and most importantly a thorough patient history are required to correctly diagnose parasitic spinal infections.

Intramedullary spinal cord lesions in an immunocompromised host due to Mycobacterium haemophilum

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M. haemophilum can produce severe disease in persons living with HIV/AIDS or other immunocompromised patients.

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The spectrum of disease caused by M. haemophilum may produce life-threatening central nervous system disease.

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The treatment of M. haemophilum when involving the CNS is challenging requiring multi-drug therapy.

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Patients with M. haemophilum central nervous system disease, with and without HIV, should be monitored for IRIS.

Mycobacterium haemophilum is a slow growing acid-fast bacillus (AFB) in the nontuberculous mycobacteria (NTM) group. M. haemophilum typically causes cervicofacial lymphadenitis in children, cutaneous diseases, septic arthritis and osteomyelitis. However, it rarely causes isolated spinal cord disease. We report the first case, to our knowledge, of isolated intramedullary spinal lesions secondary to M. haemophilum. This case involved a patient with newly diagnosed human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). He developed significant immune reconstitution inflammatory syndrome (IRIS) during his treatment. M. haemophilum should be on the differential for isolated intramedullary spinal lesions, particularly in immunocompromised patients. Given our patient’s severe IRIS, patients with HIV and M. haemophilum infection should be closely monitored for IRIS and treated aggressively. In high risk circumstances such as M. haemophilum spinal disease in patients with HIV, clinicians should consider pre-emptive treatment for IRIS.

Focal Intramedullary Spinal Cord Lesion in Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome: Toxoplasmosis Versus Lymphoma

BACKGROUND

Neurologic complications are common in patients with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). Although both the central nervous system (CNS) and the peripheral nervous system can be affected, 80% of patients with HIV/AIDS have CNS involvement during the course of their illness. The brain is the primary site of HIV/AIDS-associated CNS complications. Spinal cord involvement is rare, particularly focal intramedullary spinal cord lesions without any associated cerebral lesions. Among various opportunistic infections and malignancies, toxoplasmosis and CNS lymphoma are the most common causes of focal neurologic disease in patients with HIV/AIDS. Distinguishing between toxoplasmosis and CNS lymphoma is challenging, as the diseases have similar clinical presentations.

CASE DESCRIPTION

In a woman with newly diagnosed HIV infection, myelopathy manifested as an isolated, single intramedullary spinal cord lesion.

CONCLUSIONS

Common methods to distinguish the diagnoses of toxoplasmosis and CNS lymphoma are addressed. There should be a high index of suspicion for toxoplasmosis in patients with HIV/AIDS presenting with a focal intramedullary spinal cord lesion.

Prevalence of Toxoplasma gondii Antibodies and DNA in Iranian HIV Patients

Background & Objective:

Toxoplasma gondii infection has public health importance and can lead to serious diseases in immunosuppressed patients, such as HIV cases. Appropriate control of T. gondii infection in HIV patients requires information about the prevalence of T. gondii antibodies and DNA in different population. In this study, we aimed to determine the prevalence of Toxoplasma gondii antibodies and DNA in HIV patients in Tehran, Iran.

Methods:

A total of 149 HIV patients from the Iranian Research Center for HIV/AIDS, Tehran, Iran were enrolled in the study. Anti-Toxoplasma IgG and IgM were detected by ELISA and T. gondii DNA was evaluated by PCR and quantita- tive real-time PCR. IgG positive samples were also assessed for their avidity.

Results:

Anti-Toxoplasma IgG and IgM were positive in 46.3% and 2.7% of cases respectively. 92.7% of our patients showed past infection and 4.3% revealed recently acquired toxoplasmosis based on their IgG avidity test. T. gondii DNA was not detected by PCR but real-time PCR results showed DNA in 4.7% of total patients and 13.1% of the IgG seropositive cases.

Conclusion:

Our findings indicated that latent toxoplasmosis was relatively prevalent in our study population, but new

T. gondii infection had low prevalence. Almost half of our patients were IgG negative and at risk of acquiring toxoplasma infection. Low copy numbers of DNA were detected in 4.7% of the cases without any clinical manifestation. Therefore, detection and monitoring of anti-Toxoplasma antibodies and DNA in HIV patients is substantial to estimate the risk of reactivation and new infection.

A review on inactivation methods of Toxoplasma gondii in foods

Toxoplasmosis is an infection caused by Toxoplasma gondii, a widespread zoonotic protozoan which poses a great threat to human health and economic well-being worldwide. It is usually acquired by ingestion of water contaminated with oocysts from the feces of infected cats or by the ingestion of raw or undercooked foodstuff containing tissue cysts. The oocyst can contaminate irrigation water and fresh edible produce. It is estimated that approximately one-third of the human population worldwide harbor this parasite. Infection with T. gondii is an important cause of diseases of the central nervous system and the eye in immunocompromised and immunocompetent individuals. The purpose of this study was to evaluate the efficacy and applicability of thermal (heating, cooking, freezing and low temperature), non-thermal (high pressure processing, ionizing irradiation and curing) and chemical and biochemical (disinfection, essential oils and biochemical methods such as enzymes, nanoparticles, antibiotics and immune response) treatments for the inactivation, inhabitation or to kill T. gondii in foodstuff intended for public consumption and under experimental conditions.

Toxoplasmosis an Overlooked Disease: Seroprevalence in Cancer Patients

Background

Toxoplasmosis is one of the most important cosmopolitan life-threatening diseases in immune-compromised patients. It is caused by an intracellular protozoon: Toxoplasma gondii (T. gondii). The parasite can cause pneumonia, encephalitis or disseminated disease in immune-deficient patients and dangerous congenital anomalies in infants born to mothers infected during early pregnancies. The present study aims to evaluate the prevalence of toxoplasmosis in Egyptian cancer patients and to correlate the prevalence with type of malignancy and the different cancer treatment modalities.

Materials and Methods

Blood samples from 150 cancer patients and 50 control subjects have been examined for presence of anti-toxoplasma antibodies using a lateral flow chromatographic immunoassay.

Results

Among cancer patients included in this study, the prevalence of anti- T.gondii antibodies was 20% for IgG and 4% for IgM, while in the control group it was 8% and 2% in the same order. This difference was statistically significant for IgG (P =0.003) but not for IgM (P = 0.44). Patients with solid organ tumors treated with chemotherapy had the highest prevalence rate of toxoplasmosis (28%). It was also found higher in males (26%) than females (10%) and higher among urban (18%) than rural dwellers (16%).

Conclusion

Cancer patients showed a significantly higher rate of infection with T. gondii than their cross-matched control. For that reason, we recommend the inclusion of a screening test for toxoplasmosis in their routine workup.

Toxoplasma gondii Infection in Immunocompromised Patients: A Systematic Review and Meta-Analysis

Toxoplasma gondii has been suggested as an important opportunistic pathogen in immunocompromised patients. We conducted a global meta-analysis to assess the prevalence and odds ratios (ORs) of T. gondii infection in immunocompromised individuals. Electronic databases were reviewed for T. gondii infection in HIV/AIDS patients, cancer patients, and transplant recipients, and meta-analyses were conducted to calculate overall estimated prevalence and ORs using random or fixed-effects models. Totally, 72 eligible studies were included. The estimated pooled prevalence of T. gondii infection in immunocompromised patients and the control was 35.9 and 24.7% (p < 0.001), with an OR of 2.24, i.e., 42.1 and 32.0% for HIV/AIDS patients and the control (p < 0.05), 26.0 and 12.1% for cancer patients and the control (p < 0.001), and 42.1 and 34.5% for transplant recipients and the control (p > 0.05), whose estimated pooled ORs were 1.92 (95% CI, 1.44-2.55), 2.89 (95% CI, 2.36-3.55), and 1.51 (95% CI, 1.16-1.95), respectively. This study is the first to demonstrate that the immunocompromised patients are associated with higher odds of T. gondii infection, and appropriate prevention and control measures are highly recommended for these susceptible populations.

Infections of the spine and spinal cord

Predisposing factors for developing spinal infections include: immunodeficiency; drug abuse; the widespread use of broad-spectrum antibiotics, corticosteroids, and immunosuppressive drugs; diabetes mellitus; and spinal surgery. Infections can be bacterial, fungal, parasitic, or viral in origin. This chapter reviews current knowledge in clinical and imaging findings in the most common spinal infections divided according to the compartment primarily involved.