Clinical spectrum in 107 cases of toxoplasmic lymphadenopathy

Ocular Toxoplasmosis

INTRODUCTION

Ocular toxoplasmosis is the leading cause of posterior uveitis worldwide, affecting individuals acrossdifferent age groups. The key to reducing vision loss includes prompt diagnosis and treatment. However, despite the prevalence of ocular toxoplasmosis, there has been little consensus regarding its pathophysiology,clinical features, diagnosis, and especially management.

METHODS

The data sources were literature reviews, including Pub Med and Medline databases. Search terms included toxoplasmosis, retinitis, vasculitis, vitritis, uveitis alone or in combination with, serum, aqueous, vitreous eye, ocular and review.

RESULTS

In this review paper, we have sought to provide an overview of the pathophysiology, epidemiology, and clinical features of the disease, both based on current literature and our own clinical experience. We have also discussed the use of serology, ocular fluid, and ophthalmic investigations that could further facilitate the diagnosis of ocular toxoplasmosis.Different management strategies have been reported worldwide, including newer approaches such as local therapy.

CONCLUSION

A better understanding of critical aspects of ocular toxoplasmosis will hopefully lead to reduced morbidity, including blindness associated with this condition.

Uncommon aetiology of lymphadenopathy in a healthy child: a sporotrichosis case with painless lymphadenopathy

A 6-year-old boy was referred to the paediatric infectious disease clinic with a 2-month history of enlarged, erythematous, painless cervical lymph nodes. He initially presented to his paediatrician with a painless lesion. At that time, he was treated empirically with clindamycin and azithromycin due to a history of cat exposure. Despite treatment, the lesion evolved into a non-healing linear ulcer with painless, ascending cervical lymphadenopathy. Serologies were negative for Bartonella henselae antibodies. Additional laboratory studies revealed eosinophilia and negative Toxoplasma gondii antibodies. After no improvement following a course of trimethoprim-sulfamethoxazole, further questioning revealed that the patient had fallen into a haystack 1 month before the initial cervical lesion. The patient's parents opted to treat the infection empirically for sporotrichosis with itraconazole rather than undergo lymph node biopsy. At the 2-week follow-up, his lymphadenopathy had resolved and had returned to baseline activity.

Toxoplasmic Lymphadenitis Presenting as a Tiny Neck Tumor

(1) Background: Toxoplasmic lymphadenitis (TL), caused by the protozoan Toxoplasma gondii, is a worldwide zoonosis. We report a case of TL in the head and neck region diagnosed using ultrasound (US)-guided fine needle aspiration cytology (FNAC), serological tests, and pathological findings. (2) Case Presentation: A 51-year-old female with a chief complaint of a left posterior neck mass that had been growing for approximately 2 weeks. TL was confirmed by histopathological examinations and serological tests. US-guided FNAC and en bloc resection of the lymph node were performed. The diagnosis was confirmed as TL in the neck. (3) Conclusions: We suggest that US-guided FNAC should be considered as the first-line test for assessing a tiny mass before a definitive treatment is chosen.

The Immunogenic and Immunoprotective Activities of Recombinant Chimeric T. gondii Proteins Containing AMA1 Antigen Fragments

Toxoplasmosis, one of the most common parasitoses worldwide, is potentially dangerous for individuals with a weakened immune system, but specific immunoprophylaxis intended for humans is still lacking. Thus, efforts have been made to create an efficient universal vaccine for both animals and humans to overcome the shortcomings of currently used treatment methods and protect all hosts against toxoplasmosis. The current work represents a relatively new approach to vaccine development based on recombinant chimeric Toxoplasma gondii antigens. In the present research, three tetravalent chimeric proteins containing different portions of the parasite’s AMA1 antigen—AMA1^domainI-SAG2-GRA1-ROP1_L (A^NSGR), AMA1^{domainsII,III}-SAG2-GRA1-ROP1_L (A^CSGR) and AMA1^fullprotein-SAG2-GRA1-ROP1_L (A^FSGR)—were tested for their immunogenic and immunoprotective capacities. All tested proteins were immunogenic, as evidenced by the triggering of specific humoral and cellular immune responses in vaccinated C3H/HeOuJ mice, defined by the production of specific IgG (IgG1/IgG2a) antibodies in vivo and synthesis of key Th1/Th2 cytokines by Toxoplasma lysate antigen-stimulated splenocytes in vitro. Although all tested preparations provided partial protection against chronic toxoplasmosis in immunized and T. gondii-challenged mice, the intensity of the generated immunoprotection depended on the fragment of the AMA1 antigen incorporated into the chimeric antigen’s structure.

New-Onset Cervical Lymphadenopathy in a Patient Undergoing Treatment of Pulmonary Mycobacterium avium Complex Infection: Toxoplasmosis Lymphadenitis

Immunocompetent hosts with toxoplasmosis are usually asymptomatic. However, T. gondii can present as an acute systemic infection. Symptomatic patients usually have a benign, self-limited course that typically lasts from a few weeks to months. Herein, we present a 66-year-old immunocompetent female who developed dysphagia and new-onset cervical lymphadenopathy during pulmonary Mycobacterium avium complex treatment.

Toxoplasmosis outbreak in Brazil, 2006 - Revisited

Waterborne outbreaks of human toxoplasmosis can have great magnitude due to the number of persons infected while smaller-scale outbreaks are also possible. This is a study based on a historical database investigating a toxoplasmosis outbreak occurred in 2006 in a residential community in São Luís, in the Brazilian state of Maranhão. Ninety of the 110 residents, employees and domestic helping persons had blood samples collected and tested. The diagnosis of toxoplasmosis was established by quantification of anti-Toxoplasma gondii immunoglobulin M and immunoglobulin G antibodies using enzyme immunoassay. The subjects were classified as past infection, acute/recent infection or seronegatives. The definition of acute infection was based on the presence of indicative symptoms and immunoglobulin M positivity. There were 33 cases of acute infection. The outbreak was concluded to be waterborne: consumption of faucet-mount filtered water was indicated as risk factor. We discuss the challenges of investigating waterborne toxoplasmosis outbreaks.

Prevalence and risk factors profile of seropositive Toxoplasmosis gondii infection among apparently immunocompetent Sudanese women

Objectives

Toxoplasma gondii is an opportunistic parasite that causes a clinical manifestation known as toxoplasmosis. We investigated the prevalence and potential risk factors of T. gondii infection among women in Khartoum, Sudan. A sero-parasitological cross-sectional study included 100 women aging between 15 and 50 years old was conducted between January and November 2018. Serum samples were collected and investigated for the presence of anti-T. gondii immunoglobulins.

Results

Mean age of the women population included was 26.75 ± 8.25 with a range between 15 and 50 years. Sero-prevalence of T. gondii antibodies was 27% (27/100) with a 95% confidence interval (CI) of 18.6–36.8%. Among seropositive population 81% (22/27), 15% (4/27) and 4% (1/27) were seropositive for IgG antibodies, IgM antibodies and both antibodies respectively. Age group 21–30 years old had the highest frequency of detected IgG (10/45) and IgM (3/45). Married women had the highest frequency of detected IgG or IgM, 18/79 and 3/79, respectively. Risk factors analysis showed a total of 37/100 participants were having direct contact with cats and 66/100 have a frequent raw meat consumption, neither direct cats contact nor raw meat consumption had a statistically significant association with seropositivity to T. gondii (P value = 0.052 and 0.565, respectively).

Electronic supplementary material

The online version of this article (10.1186/s13104-019-4314-0) contains supplementary material, which is available to authorized users.

Mononucleosis Epstein -Barr negativa: variación poco reconocida de enfermedad popular

Se reporta el caso de un paciente joven, inmunocompetente y sin factores de riesgo, con adenopatías cervicales, fiebre, malestar general compatible síndrome mononucleósico. La persistencia de síntomas a pesar de múltiples tratamientos con antibióticos lleva a los médicos tratantes a echar un segundo vistazo. El hallazgo y desenlace, los hallarás aquí.

HIV-associated opportunistic CNS infections: pathophysiology, diagnosis and treatment

Nearly 30 years after the advent of antiretroviral therapy (ART), CNS opportunistic infections remain a major cause of morbidity and mortality in HIV-positive individuals. Unknown HIV-positive disease status, antiretroviral drug resistance, poor drug compliance, and recreational drug abuse are factors that continue to influence the morbidity and mortality of infections. The clinical and radiographic pattern of CNS opportunistic infections is unique in the setting of HIV infection: opportunistic infections in HIV-positive patients often have characteristic clinical and radiological presentations that can differ from the presentation of opportunistic infections in immunocompetent patients and are often sufficient to establish the diagnosis. ART in the setting of these opportunistic infections can lead to a paradoxical worsening caused by an immune reconstitution inflammatory syndrome (IRIS). In this Review, we discuss several of the most common CNS opportunistic infections: cerebral toxoplasmosis, progressive multifocal leukoencephalopathy (PML), tuberculous meningitis, cryptococcal meningitis and cytomegalovirus infection, with an emphasis on clinical pearls, pathological findings, MRI findings and treatment. Moreover, we discuss the risk factors, pathophysiology and management of IRIS. We also summarize the challenges that remain in management of CNS opportunistic infections, which includes the lack of phase II and III clinical trials, absence of antimicrobials for infections such as PML, and controversy regarding the use of corticosteroids for treatment of IRIS.

Ultrasound-guided core needle biopsy of cervical lymph nodes in the diagnosis of toxoplasmosis

BACKGROUND

Our study investigates whether the histopathological features of toxoplasmic lymphadenitis (TL), specifically noncaseating microgranuloma and follicular hyperplasia, can be obtained by sonographic-guided core needle biopsy (CNB) of cervical lymph nodes.

METHODS

Thirty-two patients seen from June 2014 to March 2015 were positive for toxoplasma immunoglobulin M antibody. Among those patients, 21 underwent CNB of a cervical lymph node and were enrolled in this study. The pathologic findings were reviewed.

RESULTS

Twenty-nine lymph nodes in 21 patients were sampled. Eighteen of the 21 (86%) patients had a microgranuloma without caseating necrosis or giant cells, and all 21 (100%) patients had follicular hyperplasia.

CONCLUSIONS

The histologic findings of TL were detected by sonographic-guided CNB, which can be used as part of the first line of investigation in patients with unexplained cervical adenopathy. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:192-196, 2017.

Toxoplasma Infection in an Immunocompetent Host: Possible Risk of Living with Multiple Cats

A 32-year-old man presented with agitation, headache, and confusion. He was immunocompetent and had been living with multiple cats for many years. His vital signs were stable. He was afebrile. Multiple blood tests did not show any serious problem. Brain magnetic resonance imaging (MRI) revealed multiple ring-enhancing white matter lesions. Cerebrospinal fluid analysis did not show any signs of infection. Based on a presumptive diagnosis of multiple sclerosis, high-dose corticosteroid treatment was started. However, this caused worsening of the symptoms and increased the size of the lesions. Corticosteroids were discontinued and biopsy was done. Biopsy of the lesions confirmed Toxoplasma gondii infection, and treatment with pyrimethamine/sulfadiazine was initiated. Treatment decreased the size of the lesions dramatically.

Toxoplasma infection of the central nervous system (CNS) is rare in immunocompetent hosts. Living with multiple cats is believed to be a risk factor for Toxoplasma infection in immunocompetent hosts.

Risk factors for acute toxoplasmosis in England and Wales

Over 300 cases of acute toxoplasmosis are confirmed by reference testing in England and Wales annually. We conducted a case-control study to identify risk factors for Toxoplasma gondii infection to inform prevention strategies. Twenty-eight cases and 27 seronegative controls participated. We compared their food history and environmental exposures using logistic regression to calculate odds ratios (OR) and 95% confidence intervals in a model controlling for age and sex. Univariable analysis showed that the odds of eating beef (OR 10·7, P < 0·001), poultry (OR 6·4, P = 0·01) or lamb/mutton (OR 4·9, P = 0·01) was higher for cases than controls. After adjustment for potential confounders a strong association between beef and infection remained (OR 5·6, P = 0·01). The small sample size was a significant limitation and larger studies are needed to fully investigate potential risk factors. The study findings emphasize the need to ensure food is thoroughly cooked and handled hygienically, especially for those in vulnerable groups.

Investigating the Determinants of Toxoplasma gondii Prevalence in Meat: A Systematic Review and Meta-Regression

BACKGROUND

Toxoplasma gondii is one of the most widespread parasites in humans and can cause severe illness in immunocompromised individuals. However, its role in healthy people is probably under-appreciated. The complex epidemiology of this protozoan recognizes several infection routes but consumption of contaminated food is likely to be the predominant one. Among food, consumption of raw and undercooked meat is a relevant route of transmission, but the role of different meat producing animal species and meats thereof is controversial.

OBJECTIVES

The aim of the present work is to summarize and analyse literature data reporting prevalence estimates of T. gondii in meat animals/meats.

DATA SOURCES

We searched Medline, Web of Science, Science Direct (last update 31/03/2015).

ELIGIBILITY CRITERIA

Relevant papers should report data from primary studies dealing with the prevalence of T. gondii in meat from livestock species as obtained through direct detection methods. Meta-analysis and meta-regression were performed.

RESULTS

Of 1915 papers screened, 69 papers were included, dealing mainly with cattle, pigs and sheep. Pooled prevalences, based on random-effect models, were 2.6% (CI95 [0.5-5.8]) for cattle, 12.3% (CI95 [7.6-17.8]) for pigs and 14.7% (CI95 [8.9-21.5]) for sheep. Due to the high heterogeneity observed, univariable and multivariable meta-regression models were fitted showing that the geographic area for cattle (p = 0.032), the farming type for pigs (p = 0.0004) and the sample composition for sheep (p = 0.03) had significant effects on the prevalences of Toxoplasma detected/estimated. Moreover, the role of different animal species was dependent on the geographic location of animals' origin.

LIMITATIONS

Limitations were due mainly to a possible publication bias.

CONCLUSIONS AND IMPLICATIONS

The present work confirms the role of meat, including beef, as T. gondii sources, and highlights the need for a control system for this parasite to be implemented along the meat production chain. Moreover, consumer knowledge should be strengthened in order to reduce the impact of disease.

Seroepidemiology of Toxoplasmosis among People Having Close Contact with Animals

A cross-sectional study was conducted to determine the seroepidemiology of Toxoplasma infection and its risk association among people having close contact with animals. A total of 312 blood samples were collected from veterinary personnel (veterinarian, technicians, and students) and pet owners from veterinary clinics and hospitals in the area of Klang Valley, Malaysia. About 4 cc of blood samples drawn from agreed participants were processed for measurement of anti-Toxoplasma IgG and IgM antibodies as well as avidity test of Toxoplasma IgG by ELISA I, II, and III kits. Meanwhile, the demographic profiles and possible risk factors of these participants were also recorded in the standardized data collection sheets. Overall seroprevalence of toxoplasmosis was observed in 62 (19.9%) participants being 7 (18.4%) in veterinarians, 15 (33.3%) in veterinary technicians, 29 (14.9%) in veterinary students, and 11 (31.4%) in pet owners. Of 19.9% Toxoplasma seropositive samples, 18.3% was positive for IgG antibody, 1.0% for IgM antibody, and 0.6% for both IgG and IgM antibodies. Of three different IgG avidity ELISA kits, ELISA III showed high avidity in all five seropositive samples (IgM and IgG/IgM antibodies) indicating chronic Toxoplasma infection which is consistent with no evidence of clinical toxoplasmosis diagnosed during the time of this study. Univariate analysis showed that age group, gender, study population, gardening, task performance, and working duration were significantly associated with Toxoplasma seropositivity. Further analysis by multivariate analysis using logistic regression showed that age group of ≥30 years old (OR = 0.34, 95% CI = 0.18-0.63, p = 0.001) and working or study duration of >10 years having close contact with animals (OR = 5.07, 95% CI = 1.80-14.24, p = 0.002) were identified as significant risks for Toxoplasma infection. Based on the results obtained, a comprehensive Toxoplasma screening and health surveillance program on toxoplasmosis should be implemented among people having close contact with animals in general and confirmed Toxoplasma seronegative individuals in particular to prevent seroconversion.

Cervical Lymph Nodes as a Selective Niche for Brucella during Oral Infections

Cervical lymph nodes (CLN) are the first lymph nodes encountered by material taking the oral route. To study their role in orally acquired infections, we analyzed 307 patients of up to 14 years treated in the university clinic of Skopje, Macedonia, for brucellosis, a zoonotic bacterial disease frequently acquired by ingestion of contaminated dairy products. From these children, 36% had lymphadenopathy. Among orally infected children, lymphadenopathy with CLN being the only lymph nodes affected was significantly more frequent as compared to those infected by contact with animals (83% vs. 63%), suggesting a possible involvement of CLN during orally acquired human brucellosis. Using a murine model where bacteria are delivered into the oral cavity, we show that Brucella quickly and selectively colonize the CLN where they proliferate and persist over long periods of time for up to 50 days post-infection. A similar efficient though less specific drainage to CLN was found for Brucella, Salmonella typhimurium and fluorescent microspheres delivered by gavage, a pathway likely representing a mixed infection mode of intragastric and oral infection, suggesting a central pathway of drained material. Microspheres as well as bacteria drained to CLN predominately reside in cells expressing CD68 and no or low levels of CD11c. Even though no systemic response could be detected, Brucella induced a locally restricted inflammatory reaction with increased expression levels of interferon γ, interleukin (IL)-6, IL-12, granzyme B and a delayed induction of Nos2. Inflammation led to pronounced lymphadenopathy, infiltration of macrophages/monocytes expressing high levels of major histocompatibility complex II and to formation of epitheloid granulomas. Together, these results highlight the role of CLN in oral infections as both, an initial and efficient trap for bacterial invaders and as possible reservoir for chronic pathogens. They likewise cast a new light on the significance of oral routes for means of vaccination.

High prevalence of anti-toxoplasma antibodies and absence of Toxoplasma gondii infection risk factors among pregnant women attending routine antenatal care in two Hospitals of Addis Ababa, Ethiopia

OBJECTIVE

Toxoplasmosis is an infection caused by the protozoan parasite Toxoplasma gondii. It is acquired mainly by eating raw or undercooked meat containing Toxoplasma gondii tissue cyst, eating food or water contaminated with oocyst, and acquiring congenital infection through the placenta. This study was conducted to determine the prevalence of toxoplasmosis and assess possible risk factors associated with the infection among pregnant women in Addis Ababa, Ethiopia.

METHOD

Cross sectional study was designed, and 288 serum samples were collected from November 1(st) 2010 to January 2011. The serum samples were tested for anti- Toxoplasma gondii antibodies using latex agglutination test. The risk factors were tested for significance using Bivariate and multivariate analysis. P-value <0.05 was considered statistically significant.

RESULT

85.4% were positive for anti Toxoplasma gondii antibody. No significant association was observed between seroprevalence and age, gestational age, socio demographic characters, history of abortion, consumption of raw or undercooked meat, consumption of raw vegetable, owning of cat, and blood transfusion.

CONCLUSION

Prevalence of toxoplasmosis among pregnant women in Addis Ababa, Ethiopia is higher than that reported from other countries. Efforts to describe risk factors for toxoplasma infection among Ethiopians should focus in children.

Antibiotics for human toxoplasmosis: a systematic review of randomized trials

The efficacy of different treatment regimens in clinical syndromes of toxoplasmosis were assessed by conducting a systematic review of published randomized clinical trials through extensive searches in MEDLINE, EMBASE, and SCOPUS with no date limits, as well as manual review of journals. Outcome measures varied depending on the clinical entity of toxoplasmosis. Risk of bias was evaluated and quality of evidence was graded. Fourteen randomized trials were included of which one was a non-comparative study. One well-designed trial showed that trimethoprim-sulphamethoxazole was more effective than placebo for clinical recovery of toxoplasmic lymphadenopathy in immunocompetent hosts. For toxoplasmic encephalopathy, efficacy of pyrimethamine+sulphadiazine and trimethoprim+sulphamethoxazole were similar, whereas pyrimethamine+sulphadiazine versus pyrimathamine+clindamycin showed no difference, irrespective of the outcome. Intravitreal clindamycin+dexamethasone and conventional treatment with oral pyrimethamine+sulphadiazine had similar efficacy with regard to all outcome measures in ocular toxoplasmosis, and intravitreal therapy was found to be safe. Adverse effects seemed more common with pyrimethamine+sulphadiazine. Most trials for encephalitis and ocular manifestations had a high risk of bias and were of poor methodological quality. There were no trials evaluating drugs for toxoplasmosis in pregnancy, or for congenital toxoplasmosis. Pyrimethamine+sulphadiazine is an effective therapy for treatment of toxoplasmic encephalitis; trimethoprim+sulphamethoxazole and pyrimethamine+clindamycin are possible alternatives. Treatment with either oral or intravitreal antibiotics seems reasonable for ocular toxoplasmosis. Overall, trial evidence for the efficacy of these drugs for toxoplasmosis is poor, and further well-designed trials are needed.

The role of the physician in laboratory medicine: a European perspective

Advances in medical laboratory technology have driven major changes in the practice of laboratory medicine over the past two decades by the development of automated, cross-disciplinary single platform analysers. This has led to the blurring of boundaries between traditional disciplines and the emergence of core automated or blood science laboratories. This paper was commissioned by the Union of European Medical Specialists to examine the changing role of laboratory-based physicians in the light of these advances by focusing on the added value of expert interpretation of test results and resultant improvements in clinical outcomes. The paper also considers the broad range of responsibilities of laboratory-based physicians and the difficulties in precisely measuring how this translates into improved clinical outcomes. Given its provenance, the paper concentrates predominantly on the role of laboratory-based physicians while acknowledging the essential and vital role of scientists in running diagnostic laboratory services.

Neuropsychiatric symptoms are common in immunocompetent adult patients with Toxoplasma gondii acute lymphadenitis

BACKGROUND

Chronic toxoplasmosis has been shown to be strongly associated with a range of neuropsychiatric effects including schizophrenia and suicide. However there have not been any prospective, community-based studies of the neuropsychiatric effects of acute toxoplasmosis in adult immunocompetent patients.

METHODS

Adult patients with a positive serum IgM anti-Toxoplasma gondii test result, in the context of an acute illness with lymphadenopathy, were invited to complete a questionnaire seeking information relating to the nature, severity, and duration of symptoms in the months following the diagnosis of acute toxoplasmosis.

RESULTS

Laboratory testing identified a total of 187 adults who had a positive serum IgM anti-T. gondii test result between 1 January and 30 November 2011. Consent to contact 108/187 (58%) patients was provided by their family doctor; 37 (34%) of these 108 patients completed and returned the questionnaire. Questionnaires from the 31/108 (29%) patients who reported swollen lymph nodes during their illness were included in the study. Fatigue (90%), headache (74%), difficulty concentrating (52%), and muscle aches (52%) were the most commonly reported symptoms. These symptoms commonly persisted for at least 4 weeks. Twenty-seven of 31 (87%) subjects reported a moderate or severe reduction in their overall physical and mental health during the first 2 months of illness.

CONCLUSIONS

Acute toxoplasmosis in immunocompetent adults commonly causes moderately severe neuropsychiatric symptoms that might result from replication of the organism in the central nervous system with consequent effects on brain function. Patients should be advised that such symptoms are common and reassured that they usually resolve completely within a few months.

Toxoplasmosis not transmitted by cat bite, but high prevalence of antibodies to Toxoplasma gondii in patients bitten by their own cat

The aims of the study were to investigate the prevalence of antibodies to Toxoplasma gondii in a group of patients bitten by cats, and also to determine if toxoplasmosis can be transferred by cat bite. Seventy-two patients who attended the emergency wards at 3 hospitals in Stockholm, Sweden, due to infection by cat bite, were investigated for specific IgM and IgG antibodies to T. gondii in the acute phase, as well as in the convalescent phase about 2 weeks later. Specific IgG antibodies to T. gondii (> or =8 IU/ml) were found in 17/72 patients (24%) in the acute phase. No case of seroconversion occurred. Patients who were bitten by their own cat had positive antibody titres to T. gondii significantly more often than those bitten by a foreign cat; 30% and 5%, respectively (p = 0.02). This suggests that regular contact with cats may contribute to the transmission of the parasite.

Use of dense granule antigen GRA6 in an immunoglobulin G avidity test to exclude acute Toxoplasma gondii infection during pregnancy

The usefulness of a specific immunoglobulin G (IgG) avidity enzyme-linked immunosorbent assay (ELISA) based on recombinant GRA6 antigen for distinguishing between acute and chronic Toxoplasma infection was investigated. Two sets of serum samples obtained from pregnant women with acute, chronic, or no Toxoplasma infection collected in France and Iran were used. Among the French subjects, 19 of 20 (95%) women who experienced seroconversion during the past 4 months before sampling displayed low-avidity IgG antibodies against GRA6, while all 17 (100%) women with chronic infection had high-avidity antibodies. When the Euroimmun IgG avidity ELISA was used, 15 of 19 (78.9%) recently infected women had low-avidity antibodies, and 20 of 22 (90.9%) women with chronic infection displayed high-avidity antibodies. The results suggested better performance of the GRA6 avidity ELISA than the Euroimmun avidity ELISA for exclusion of a recent infection occurring less than 4 months previously. Similarly, all 35 Iranian women with acute Toxoplasma infection had low-avidity antibodies against GRA6, whereas all 34 women with chronic infection displayed IgG antibodies of high avidity, indicating the value of GRA6 avidity testing for ruling out a recent infection. Avidity tests based on lysed whole-cell Toxoplasma gondii antigen are currently used to exclude recently acquired infections; however, the use of recombinant antigen(s) might improve the diagnostic performance of avidity tests and facilitate the development of more standardized assays.

Treatment of toxoplasmic lymphadenitis with co-trimoxazole: double-blind, randomized clinical trial

BACKGROUND

Lymphadenitis is one of the presenting signs of toxoplasmosis. Co-trimoxazole (CTM) has a good therapeutic effect on ocular and cerebral infections caused by Toxoplasma gondii. Since this infection is endemic in Ahvaz and because of the lack of investigations into the therapeutic effects of CTM in toxoplasmic lymphadenitis (TL), this study was performed from 2005 to 2007 to determine the therapeutic effects of CTM on TL in Ahvaz.

METHODS

Forty-six patients with TL were enrolled in this randomized, double-blind, placebo-controlled trial study. Diagnosis was based on clinical examination, serological tests (chemiluminescent), and histopathological examinations. Palpable lymph nodes, IgM >8IU, and follicular hyperplasia were defined as positive findings. Patients were randomly assigned to the comparison groups (23 patients in each group). The CTM patients were treated with 48 mg/kg/day CTM divided into two doses, for 1 month. The placebo patients were treated with placebo for 1 month. The primary endpoint for treatment response was 1 month. Follow-up with physical and serological examinations occurred at 6 months. The secondary endpoint was at 6 months. Clinical response was defined as no palpable lymph nodes and serological response as IgM <6IU; a patient was cured if the lymph nodes were no longer palpable and IgM was <6IU. Results were analyzed using SPSS software and the Chi-square test.

RESULTS

At the end of treatment, a clinical response was observed in 15 (65.2%) in the CTM group and five (21.7%) in the placebo group. A serological response was seen in 65.2% of the CTM group and 13.0% of the placebo group. The cure rate was 65.2% in the CTM group and 13.1% in the placebo group. There was a significant difference in therapeutic effect between the two groups (52.2%, 95% confidence interval 32.1-72%, p<0.001). There was no difference in the site of infection between the two groups (p>0.05).

CONCLUSION

CTM has a good therapeutic effect in TL and may be used in selected patients for whom treatment is required.

Acute acquired toxoplasmosis: clinical-laboratorial aspects and ophthalmologic evaluation in a cohort of immunocompetent patients

Most cases of acute acquired toxoplasmosis (AAT) are oligosymptomatic and self-limited. Therefore, these infections rarely indicate treatment. Prospective studies of AAT patients are rare in the medical literature. The frequency of systemic manifestations has not been sufficiently studied. In order to search for risks factors for systemic and ocular involvement, 37 patients were submitted to a diagnostic investigative protocol. The most frequent findings were lymph node enlargement (94.6%), asthenia (86.5%), headache (70.3%), fever (67.6%) and weight loss (62.2%). Hepatomegaly and/or splenomegaly were present in 21.6% of cases (8/37). Liver transaminases were elevated in 11 patients (29.7%) and lactic dehydrogenase in 17 patients (45.9%). Anaemia was found in four patients (10.8%), leucopoenia in six patients (16.2%), lymphocytosis in 14 patients (37.8%) and thrombocytopenia in one patient (2.7%). Fundoscopic examination revealed retinochoroiditis in four patients (10.8%). No statistical association was found between any one morbidity and retinochoroiditis. Nevertheless, a significant association was found between the presence of more than eight morbidity features at evaluation and long-lasting disease. An ideal diagnostic protocol for AAT would include evidence of systemic involvement. Such a protocol could be used when planning treatment.

Toxoplasmosis: A history of clinical observations

It has been 100 years since Toxoplasma gondii was initially described in Tunis by Nicolle and Manceaux (1908) in the tissues of the gundi (Ctenodoactylus gundi) and in Brazil by Splendore (1908) in the tissues of a rabbit. Toxoplasma gondii is a ubiquitous, Apicomplexan parasite of warm-blooded animals that can cause several clinical syndromes including encephalitis, chorioretinitis, congenital infection and neonatal mortality. Fifteen years after the description of T. gondii by Nicolle and Manceaux a fatal case of toxoplasmosis in a child was reported by Janků. In 1939 Wolf, Cowen and Paige were the first to conclusively identify T. gondii as a cause of human disease. This review examines the clinical manifestations of infection with T. gondii and the history of the discovery of these manifestations.

Assessment of the value of detecting specific IgA antibodies for the diagnosis of a recently acquired primary Toxoplasma infection

OBJECTIVE

To assess the value of detecting IgA antibodies for the diagnosis of a recently acquired primary Toxoplasma infection.

METHODS

IgA antibodies were screened in sera from 87 women with different serological profiles of Toxoplasma gondii IgM and IgG antibodies and Toxoplasma-specific IgG avidity. The IgM and IgG antibodies and the IgG avidity were measured with an automated Vitek Immuno Diagnostic Assay System (VIDAS). Anti-T.gondii IgA was measured with Platelia Toxo IgA TMB kits.

RESULTS

All 12 sera obtained from women with clinical and/or serological evidence of a recently acquired Toxoplasma infection were positive for IgA. In 42 serum samples obtained more than 6 months after T. gondii infection from women with no clinical evidence of infection, but who had a positive IgM test and a high IgG avidity index, the IgA-enzyme linked immunosorbent assay (ELISA) test results were positive, negative, and doubtful in 16 (38.1%), 23 (54.8%), and 3 (7.1%) sera, respectively. In eight women, IgA was detected in sera collected more than 9 months after the onset of infection. The IgA test result was also positive in 11 of 12 sera (91.7%) obtained from women with no clinical evidence of toxoplasmosis, but who had a positive IgM test and a borderline IgG avidity index. The IgA-ELISA was negative in 21 sera obtained more than 2 years after the onset of T. gondii infection from women with no clinical evidence of toxoplasmosis, but who had a negative IgM test and a positive IgG test.

CONCLUSION

These results show that IgA is not a dependable marker for a recently acquired primary Toxoplasma infection.

Donor-transmitted toxoplasmosis in liver transplant recipients: a case report and literature review

Transmission of toxoplasmosis via liver transplantation is extremely uncommon. Here we report the case of a 52-year-old male liver transplant recipient who on day 32 post transplant developed pneumonia followed by respiratory failure. Donor-transmitted toxoplasmosis was confirmed as the etiology by both serologic and molecular testing. We also review all previously published cases of toxoplasmosis in the English-language adult liver transplant literature.

IgG avidity assay firms up the diagnosis of acute toxoplasmosis on the first serum sample in immunocompetent pregnant women

Rapid diagnosis of acute toxoplasmosis during pregnancy permits timely treatment and prevents or attenuates congenital toxoplasmosis. Specific IgM antibodies to Toxoplasma as marker of acute infection are often poorly informative, meaning that a complementary technique is needed to reach a diagnosis on the first sample. Here we evaluated 2 commercial kits designed to assist with the diagnosis of acute toxoplasmosis: Platelia Toxo IgG Avidity Complementary Reagents and Platelia Toxo IgA, both from BIO-RAD (Marnes La Coquette, France). We tested 2 groups of subjects: 36 patients with acute toxoplasmosis and 55 patients with chronic toxoplasmosis. The IgG avidity test had a sensitivity of 100% (36/36), a specificity of 92.7% (51/55), a positive predictive value of 90%, and a negative predictive value of 100%. Among the immunocompetent women population, the avidity test had perfect sensitivity and specificity, and positive and negative predictive values of 100%. The IgA test had a sensitivity of 88.8% (32/36) and a specificity of 85.4% (47/55), and positive and negative predictive values of 80% and 92.1%, respectively. When the 2 tests were combined, there was only 1 case in which the diagnosis of chronic toxoplasmosis could not be confirmed. The IgG avidity test can therefore be used to rapidly distinguish between chronic and acute infection on the first sample from a pregnant woman, provided there is no underlying immunodepression and no ongoing antitoxoplasmic treatment. In these 2 situations, the results must be interpreted with care, and other serologic markers, including IgA, should be tested. Determination of a pregnant woman's status on a first serum sample allows therapeutic and preventive management to be started without delay.

The differential agglutination test as a diagnostic aid in cases of toxoplasmic lymphadenitis

Lymphadenopathy (LN) is the most common clinical manifestation of acute acquired toxoplasma infection in humans. The diagnosis of toxoplasmic lymphadenitis (TL) is established by serological methods and/or lymph node biopsy. In the United States, the differential agglutination (of acetone [AC]-fixed versus that of formalin [HS]-fixed tachyzoites) test (AC/HS test) has primarily been used in assessments of pregnant women as a component of the toxoplasma serological profile to distinguish between recently acquired infections and infections acquired in the distant past. We studied the AC/HS test in patients with TL to define its usefulness in diagnosing individuals presenting with LN and to determine its kinetics after the onset of LN. One hundred nine consecutive patients (158 serum samples) diagnosed serologically and by lymph node biopsy as having TL were studied. Specific patterns in the AC/HS test were noted to be dependent on the time from the clinical onset of LN (COLN). Acute AC/HS patterns were observed for more than 75% of patients who according to their histories had developed their TL within 6 months after COLN. Acute patterns were not observed beyond the 12th month except for a single patient for whom an acute pattern (400/800) persisted to the 13th month after COLN. Equivocal patterns were observed up to 36 months after COLN. Nonacute patterns were observed only for serum samples drawn at least 13 months after COLN. A nonacute pattern in an individual at less than 12 months after COLN should suggest an etiology other than TL. In such cases, investigation for alternative causes, including malignancy, should be instigated.

[Acute toxoplasmosis: clinical and laboratory data in eleven patients]

INTRODUCTION

The clinical and laboratory data of immunocompetent patients with acute toxoplasmosis (AT) are described.

PATIENTS AND METHODS

We performed a retrospective study of patients with AT attended between 1996 and 2004. Diagnostic criteria consisted of compatible clinical findings (generalized and cervical lymphadenopathies) and specific serology against Toxoplasma gondii (high IgG and IgM and/or reactive IgA). IgG and IgM determinations were performed by ELFA and IgA determinations by ELISA. IgM-CMV, heterophil antibodies, hemogram, hepatic chemistry were also determined and funduscopic examination was performed.

RESULTS

Eleven immunocompetent patients with AT were evaluated. The mean age was 8.8 years (95 % CI: 3.6-12.9). The patients were evaluated between the first and the third month after symptom onset. Of the 11 patients, hard elastic lymphadenopathies were found in 10, single cervical lymphadenectomy in three and generalized lymphadenectomy in seven. One patient showed no symptoms. In one patient, nodal histology showed the Piringer-Kuchinka triad. None of the patients showed alterations in the hemogram, hepatic chemistry or funduscopic examination. The mean IgG value was 4.143 UI/ml (95 % CI: 2.570 and 5.717). IgM was reactive in nine of the 11 patients (81.8 %) and IgA in seven out of 10 patients (70 %). In all patients, at least one of these two immunoglobulins was reactive. In all patients, clinical outcome was favorable without parasiticide treatment.

CONCLUSION

Except for one asymptomatic patient, all the patients had generalized lymphadenopathies and only 27.2 % showed cervical lymphadenopathies. A negative IgM or IgA result does not rule out a diagnosis of AT. Parasiticide treatment is unnecessary in this entity. Acute toxoplasmosis should be considered early in children with lymphadenopathies to avoid invasive procedures.

Seroprevalence of Toxoplasma gondii in Sweden, Estonia and Iceland

Toxoplasmosis is a disease caused by the intracellular protozoan parasite, Toxoplasma gondii which infects up to one-third of the world human population. Toxoplasmosis in neonates and immunocompromised patients can lead to severe disease and death. We investigated the prevalence and risk factors for T. gondii infection in Iceland, Sweden and Estonia, and tested the hypothesis that T. gondii infection causes systemic inflammation and protects against atopy. Blood samples were collected from 1277 randomly selected subjects. The presence of T. gondii IgG antibodies was determined by an ELISA method and levels of Hs-CRP by immunoturbidimetric assay. The prevalence of T. gondii antibodies was 54.9% in Tartu, 23% in Uppsala and 9.8% in Reykjavik (p<0.0001). The risk of positive T. gondii antibodies increased with the number of siblings and with age in Sweden. T. gondii infection was associated with asthma related symptoms and increased Hs-CRP (p = 0.02). No association was found with IgE-sensitization and lung function. We concluded that risk factors for T. gondii infection suggested that soil exposure was 1 of the mechanisms in all 3 countries and a meat-associated infection route is a risk in Sweden.

Facial asymmetry with nasal and orbital involvement in a case of sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease)

Sinus histiocytosis with massive lymphadenopathy or "Rosai-Dorfman"s syndrome is a rare benign disease of unknown etiology, usually seen in younger patients. A 12-year-old boy of the disease presented with facial asymmetry, massive lymphadenopathy, nasal and orbital manifestation is reported. Diagnosis was performed by superficial lymph node biopsy. No immunodeficiency was found. Local excision of the orbital lesion and endonasal endoscopic resection of the disease from nasal, paranasal sinuses, and nasopharynx was achieved effectively. The clinical presentation, histologic characteristics, pathogenesis and treatment of this case is discussed. This is the first reported case, to the best of our knowledge, of the disease to be associated with facial asymmetry.

Evaluation of the immunoglobulin G avidity test for diagnosis of toxoplasmic lymphadenopathy

Toxoplasmic lymphadenopathy (TL) is the most common clinical manifestation of acute acquired toxoplasma infection in normal individuals. The diagnosis is established by serologic methods and lymph node biopsy. Recently, tests for avidity of toxoplasma immunoglobulin G (IgG) antibodies have been introduced to help discriminate between recently acquired and distant infection with the parasite. We studied an avidity test to define the usefulness of this method and to determine the evolution of the IgG avidity in TL. Seventy-three consecutive patients diagnosed as having TL were studied. IgG avidity test titers were noted to be time dependent from the clinical onset of lymphadenopathy. Low IgG avidity test results were observed in patients who had developed lymphadenopathy from <1 month to 17 months prior to the sampling of sera, emphasizing that low IgG avidity test results are not reliable for diagnosis of recently acquired infection. In contrast, high IgG avidity test results were observed only in patients who had developed lymphadenopathy at least 4 months earlier. Thus, a high IgG avidity test result in an individual who has recent onset of lymphadenopathy (e.g., within 2 to 3 months of sera sampling) suggests a cause other than toxoplasmosis. In such cases, further workup is warranted in order to determine the cause of the lymphadenopathy.

Toxoplasmic lymphadenitis--clinical and serologic profile

OBJECTIVE

To study the serologic profile of several types of test for toxoplasmosis, in order to contribute to the interpretation of antibody kinetics.

METHODS

The clinical and serologic features of 120 cases of lymphadenopathy with known time of clinical onset were studied during 18 months postinfection. Antibody kinetics was determined by Sabin-Feldman dye test, complement fixation with light antigen, IgM immunofluorescent antibody test, and IgM immunosorbent agglutination assay (IgM-ISAGA). Cell-mediated immunity was evaluated by the toxoplasmin skin test.

RESULTS

Seventy-five female patients aged 11-54 years (median 27 years) and 45 male patients aged 3-59 years (median 17 years) were studied, 85% of whom were under 30 years of age. Cervical lymph nodes were involved throughout, generally on both sides, with more than one affected ganglion group in 88%. The predominant symptom was asthenia (69%), which persisted in some cases for several months. A negative Sabin-Feldman dye test in a lymphadenopathy with more than three weeks' evolution excludes a toxoplasma etiology. A positive Sabin-Feldman dye test with negative IgM-ISAGA almost invariably excludes recent infection. The Sabin-Feldman dye test was positive in 94% of patients with titers higher than 1 : 16 000 within the first three months. The IgM-ISAGA yielded 98% of positive results, of which 94% were high titers. Titers >/= 1 : 160 in the IgM immunofluorescent antibody test and complement fixation were found to be highly indicative of recent infection, since 87% and 91%, respectively, were found within the first three months. A negative skin test plus positive serology values indicates recent infection.

CONCLUSION

Our results indicate that estimation of time of infection on the basis of serologic results is improved by the simultaneous application of several tests, and correlates closely with the presence of clinical lymphadenitis.

B-mode sonographic criteria for differential diagnosis of cervicofacial lymphadenopathy in cat-scratch disease and toxoplasmosis

BACKGROUND

Our purpose was to evaluate different sonographic parameters of cervicofacial lymphadenopathy caused by cat-scratch disease (CSD) and toxoplasmosis.

METHODS

By use of high-resolution B-mode sonography a total of 552 lymph nodes in the head and neck were detected between January 1997 and December 2001. There were 71 patients (422 lymph nodes) with CSD and 19 patients (130 lymph nodes) with toxoplasmosis. Sonographic variables, including 20 sonomorphologic features along with age and gender, were analyzed with multivariate logistic regression.

RESULTS

Heterogenous lymph nodes were more often found in CSD (p =.003), and nonsharp nodal borders showed a significant association with CSD (p =.0005). Multivariate analysis identified sharpness of borders (p =.0001), S/L ratio (p =.0006), and type of lymphadenopathy (acute, abscessed, chronic) (p =.0006) as most significant for differentiating between CSD and toxoplasmosis.

CONCLUSIONS

These results provide significant and useful criteria for ultrasonographic differentiation between CSD and toxoplasmosis.

Severe acute disseminated toxoplasmosis acquired by an immunocompetent patient in French Guiana

Disseminated toxoplasmosis during acute infections has rarely been observed in immunocompetent patients. We report a case of severe acute disseminated toxoplasmosis acquired by an immunocompetent patient in French Guiana and review the literature.

Dismantling the germinal center: comparing the processes of transformation, regression, and fragmentation of the lymphoid follicle

The pathologic and immunologic features of the formation of the germinal center have been extensively studied. The process of dissolution of the germinal center is not as well understood. Different patterns of germinal-center breakdown are commonly encountered in diagnostic lymph node biopsy specimens and frequently present difficulties in diagnosis. The current immunologic understanding of germinal-center dynamics is reviewed and correlated with the histologic and immunophenotypic features of three broad classes of germinal center dissolution, namely progressive transformation, regression, and follicle fragmentation. The author suggests that these different patterns represent alternate responses to antigenic stimulation. The relationships of progressive transformation to Hodgkin's disease and of follicular regression to Castleman's disease are discussed.

Antenatal screening for hepatitis B and antibodies to Toxoplasma gondii and rubella virus: evaluation of two commercial immunoassay systems

A comparative evaluation of the Abbott AxSYM and DPC Immulite random-access analyzers was performed using 497 prospectively collected serum samples. These samples were sent to the laboratory for routine antenatal screening for hepatitis B surface antigen and immunoglobulin G (IgG) and IgM antibodies to Toxoplasma gondii and rubella virus. The overall agreement between the two assay systems ranged from 97.4 to 100%. After discrepancy analysis, the outcome in terms of sensitivity and specificity varied from 98.2 to 100% for all but one of the assays tested. The AxSYM rubella virus IgG assay tended to report protective or indeterminate antibody levels in 1% of the samples. This shortcoming might be overcome by raising the cutoff of the microparticle enzyme immunoassay system.

Application of a prediction rule to select which patients presenting with lymphadenopathy should undergo a lymph node biopsy

We conducted the present study to develop a clinical prediction rule for discriminating which patients with peripheral lymphadenopathy require a lymph node biopsy. The clinical features of 315 patients with peripheral lymphadenopathy were analyzed to develop the prediction rule: 83 had diseases requiring a lymph node biopsy (Lymph Node Biopsy Group [BG]), while 232 had diseases that could be diagnosed without a lymph node biopsy (Non-Lymph Node Biopsy Group [NBG]). Among 23 examined clinical covariates, we identified 6 that independently predicted the need for lymph node biopsy and were graded as follows: 1) Age: x1 = 0, if < or = 40 years and 1, if > 40 years. 2) Tenderness in palpation: x2 = 0, if absent and 1, if present. 3) Size of the greatest lymph node: x3 = 0, if < 1.0 cm2, 1 if 1.0-3.99 cm2, 2 if 4.0-8.99 cm2, and 3 if > or = 9.0 cm2. 4) Generalized pruritus: x4 = 1, if present and 0, if not. 5) Supraclavicular lymphadenopathy: x5 = 1, if present and 0, if not. 6) Texture: x6 = 1, if nodes are hard and 0, if not. The prediction rule was then validated in a subsequent group of 160 patients (32 in the BG; 128 in the NBG). A score Z = 5x1 - 5x2 + 4x3 + 4x4 + 3x5 + 2x6 - 6 corresponded to every patient, according to the results of logistic regression analysis. If patients with Z > or = 1 were considered to need lymph node biopsy, the sensitivity of the prediction rule was 95.2% (95% confidence intervals [CI]: 88.1%-98.1%) and the specificity was 81.0% (95% CI: 75.4%-85.6%). Within the Validation Group of patients the prediction rule was at least equally effective. Sensitivity was 96.9% (95% CI: 83.9%-99.5%) and specificity was 91.4% (95% CI: 85.1%-95.2%). The described rule can be useful in the clinical evaluation of patients with peripheral lymphadenopathy. Further validation by other groups is required, and its cost-effectiveness has to be investigated.