Diagnosis of pulmonary infection with Toxoplasma gondii in immunocompromised HIV-positive patients by real-time PCR

The aim of the study presented here was to evaluate the use of PCR for improving the diagnosis of Toxoplasma gondii infection in immunocompromised hosts. Three hundred thirty-two bronchoalveolar lavage (BAL) fluid samples were analyzed by real-time PCR targeting a 529 bp element of T. gondii. In positive samples, the genotype of the parasite was determined by sequence analysis of the GRA6 gene. Positive results were achieved for 2% (7/332) of the samples tested. Genotyping was possible in two samples and revealed GRA6 type II T. gondii. PCR for detecting T. gondii in BAL samples should be performed in all immunosuppressed HIV-positive patients with symptoms of a systemic infection of unknown etiology. Trimethoprim-sulfamethoxazole prophylaxis does not exclude concomitant infection with T. gondii.     

A randomized trial of the discontinuation of primary and secondary prophylaxis against Pneumocystis carinii pneumonia after highly active antiretroviral therapy in patients with HIV infection. Grupo de Estudio del SIDA 04/98

BACKGROUND: Prophylaxis against Pneumocystis carinii pneumonia is indicated in patients with human immunodeficiency virus (HIV) infection who have less than 200 CD4 cells per cubic millimeter and in those with a history of P. carinii pneumonia. However, it is not clear whether prophylaxis can be safely discontinued after CD4 cell counts increase in response to highly active antiretroviral therapy. METHODS: We conducted a randomized trial of the discontinuation of primary or secondary prophylaxis against P. carinii pneumonia in HIV-infected patients with a sustained response to antiviral therapy, defined by a CD4 cell count of 200 or more per cubic millimeter and plasma HIV type 1 (HIV-1) RNA level of less than 5000 copies per milliliter for at least three months. Prophylactic treatment was restarted if the CD4 cell count declined to less than 200 per cubic millimeter. RESULTS: The 474 patients receiving primary prophylaxis had a median CD4 cell count at entry of 342 per cubic millimeter, and 38 percent had detectable HIV-1 RNA. After a median follow-up period of 20 months (758 person-years), there had been no episodes of P. carinii pneumonia in the 240 patients who discontinued prophylaxis (95 percent confidence interval, 0 to 0.85 episode per 100 person-years). For the 113 patients receiving secondary prophylaxis, the median CD4 cell count at entry was 355 per cubic millimeter, and 24 percent had detectable HIV-1 RNA. After a median follow-up period of 12 months (123 person-years), there had been no episodes of P. carinii pneumonia in the 60 patients who discontinued prophylaxis (95 percent confidence interval, 0 to 4.5 episodes per 100 person-years). CONCLUSIONS: In HIV-infected patients receiving highly active antiretroviral therapy, primary and secondary prophylaxis against P. carinii pneumonia can be safely discontinued after the CD4 cell count has increased to 200 or more per cubic millimeter for more than three months.     

Role of TNF and IL-1 in infections with Toxoplasma gondii.

Mice lethally infected with the C56 strain of Toxoplasma gondii and treated with purified recombinant murine tumour necrosis factor (TNF, 1 microgram/day/mouse for 8 days), recombinant human interleukin-1 (IL-1 alpha or IL-1 beta, 100 ng/day/mouse for 5 days) or a single dose of a combination of TNF (1 microgram/mouse) and IL-1 alpha or IL-1 beta (100 ng/mouse) were significantly protected against death (P less than 0.05-0.001, as compared with untreated infected controls). Mice infected with 100,000 tachyzoites of the highly virulent RH strain of T. gondii released serum TNF in relation to the time after infection and were primed to secrete an enhanced level of serum TNF upon stimulation with bacterial lipopolysaccharide (LPS). In vitro studies showed that interferon-gamma (IFN-gamma) increased the antimicrobial activity of murine peritoneal macrophages whereas TNF, IL-1 alpha and IL-1 beta did not. TNF, however, synergized with the anti-toxoplasmic effect provided by IFN-gamma and this activity was blocked by anti-TNF antibodies. IFN-gamma induced the production of TNF and the anti-toxoplasmic effect provided by IFN-gamma seemed to be dependent partly on the production of TNF. We conclude that TNF and IL-1 may play a significant role in modulating the host's immune defence against T. gondii infection.     

Breakthrough invasive fungal disease in patients receiving posaconazole primary prophylaxis: a 4-year study

Posaconazole (PSC) is currently recommended as primary prophylaxis in neutropenic patients with acute myeloid leukaemia (AML) and in allogenic haematopoietic stem cell transplantation (AHSCT) recipients with graft-versus-host disease (GVHD). Studies focusing on breakthrough invasive fungal disease (IFD) upon PSC prophylaxis show disparate results. In order to evaluate the incidence of IFD in patients on PSC prophylaxis and identify IFD risk factors, we carried out a retrospective study of all consecutive patients on PP from January 2007 to December 2010 in our hospital. Breakthrough IFDs were identified from the database of the central pharmacy and the French administrative database (PMSI), registering final medical diagnoses of hospitalized patients. Medical data were reviewed to study proven or probable IFD, according to EORTC/MSG definition. PSC plasma concentrations (PPC) were also retrieved. Poisson models were used for statistical analysis. Two hundred and seventy-nine patients received PSC prophylaxis for a median duration of 1.4 months (range 0.2–17.9). Proven (n = 6) or probable (n = 3) IFDs were diagnosed in nine cases (3.2%). IFD incidence rate per 100 person-month was 1.65 (95% CI, 0.79–2.97). IFDs were candidaemia (Candida glabrata, n = 2), pulmonary invasive aspergillosis (n = 3), disseminated fusariosis (n = 2) and pulmonary mucormycosis (n = 2). Seven deaths were reported, directly related to IFD in three patients (33.3%). First dosage of PPC under 0.3 mg/L was the single significant risk factor for IFD (RR, 7.77; 95% CI, 1.30–46.5; p 0.025). Breakthrough IFD in patients receiving PSC prophylaxis is rare but associated with a poor outcome. Low PSC plasma concentrations are associated with an increased risk of IFD.     

Effectiveness of a brief advance directive intervention in primary care: a randomized clinical trial

ObjectiveTo measure the effectiveness of a brief intervention aimed at increasing interest in and use of advanced directives (AD) among primary care patients.MethodsRandomized controlled trial. In the intervention arm, patients were given brief oral information and a leaflet on AD by General Practitioners (GPs), in the control group were briefly informed about the study’s purpose. Outcome variables were the proportion of patients who expressed interest in AD and those who completed one. Covariates were sex, age, education, race, Charlson comorbidity index (CCI), religion, and possession of financial will.ResultsOverall, 332 patients were recruited; 58 in the intervention and 36 in the control group expressed interest in AD (p = 0.033) and 18 (5.4 %) made an AD (nine in each group). Variables associated with interest were Caucasian race (odds ratio [OR], 1.88), the intervention (OR, 1.86), and CCI extreme scores (OR, 0.36). Variables associated with AD completion were primary education/no schooling (OR, 5.69) and fewer children (OR, 0.57).ConclusionsA brief oral and written intervention delivered by GP significantly increased interest in AD and achieved a completion rate of 5.4 %, without differences with the control group.Practice ImplicationsAD interventions should focus on individuals already likely to be motivated.     

A one-session treatment for patients suffering from medically unexplained symptoms in primary care: a randomized clinical trial

The aim of the study was to evaluate a one-session cognitive-behavior treatment (CBT) versus standard medical care for 140 primary-care patients with multiple somatoform symptoms. DSM-IV diagnoses were assessed with structured interviews. Primary outcome variables were healthcare utilization, number, and severity of somatoform symptoms, and secondary outcome measures were psychopathology dimensions. Assessments were done at study enrollment, at 4-weeks, and at 6-month follow-up. General acceptance of CBT was high (positive session evaluations, low dropout rate: 15%). Using an intent-to-treat analytic strategy, both groups improved. Yet results showed a stronger reduction in doctor visits and somatization severity in CBT versus standard care.     

The prevalence and determinants of depression among HIV-positive perinatal women receiving antiretroviral therapy in India

Archives of Women's Mental Health - To assess the prevalence and correlates of perinatal depression, 200 HIV-positive pregnant/post-partum women receiving antiretroviral therapy (ART) were...     

Diagnosis of Sarcocystis cruzi, Neospora caninum, and Toxoplasma gondii infections in cattle

The aim of the study was to diagnose Sarcocystis sp. infections in cattle and to detect coinfections by Toxoplasma gondii and/or Neospora caninum. Blood, diaphragm, esophagus, and myocardium from 90 beef cattle from Argentina were collected. Histopathological, immunohistochemical, polymerase chain reaction assays, and direct microscopical examination were carried out. Sarcocysts from myocardium were measured and counted. Indirect fluorescent antibody test (IFAT) for the three protozoans was performed. Sarcocystis cruzi sarcocysts were found in 100% of myocardium samples. Sarcocysts per gram ranged from 8 to 380 with higher values found in adult cattle (p < 0.001). T. gondii and N. caninum were not detected by immunohistochemistry. T. gondii DNA was found in myocardium of 2/20 seropositive animals, while N. caninum DNA was not found. Antibodies against S. cruzi were detected in all samples, those against N. caninum in 73% and against T. gondii in 91% of the samples (IFAT titer ≥25). It is concluded that serology by IFAT is a suitable method to diagnose these protozoan infections due to its specific IgG detection; therefore, IFAT may be a useful tool to evaluate the impact of each protozoan infection in coinfected animals. Financial support for this study was provided by SeCyT through BID 1728 PICT No. 10858/8.     

Piperacillin/tazobactam versus imipenem/cilastatin for severe diabetic foot infections: a prospective,randomized clinical trial in a university hospital

In this prospective, randomized, open-label clinical trial, we compared the efficacy and safety of two antibiotic regimens for severe diabetic foot infections (DFI). Sixty-two in-patients with DFI received either piperacillin/tazobactam (Pip-Tazo, n = 30) (4.5 g intravenously every 8h) or imipenem/cilastatin (IMP, n = 32) (0.5 g intravenously every 6h). The mean duration of treatment was 21 days for Pip-Tazo and 24 days for IMP. Twenty-two (73.3%) patients in the Pip-Tazo group and 26 (81.2%) patients in the IMP group had DFI associated with osteomyelitis. Successful clinical response was seen in 14 (46.7%) patients in the Pip-Tazo group and in nine (28.1%) patients in the IMP group [relative risk (RR) 1.6 (95% CI 0.84–3.25), p 0.130]. Two patients in the IMP group and none in the PIP-Tazo group relapsed [RR 2 (0.94–4.24), p 0.058]. Eighty-nine microorganisms were isolated: 38 (43%) Gram-positive and 51(57%) Gram-negative. Among patients with positive culture, 47 (96%) had complete and two (4%) had partial microbiological response. Microbiological response rates were similar in both groups (p 1.000). Amputation was performed in 18 (60%) and 22 (69%) patients in the Pip-Tazo and IMP groups (p 0.739) respectively. Side effects were more common in the Pip-Tazo group (30% vs. 9.4%), but they were generally mild and reversible. In conclusion, although the sample size was small and the results did not reach statistical significance, Pip-Tazo produced a better clinical response rate than IMP in the treatment of severe DFI. There was no significant difference between the treatment groups with respect to microbiological response, relapse and amputation rates.     

A randomized trial of a brief mental health intervention for primary care patients

This randomized trial is a first evaluation of a brief psychotherapeutic intervention for primary care patients. Sixty-two participants were randomly assigned to the intervention or to treatment as usual. As compared with treatment as usual, the intervention led to significant reductions in symptoms of anxiety and depression. The reduction was maintained for 3 months after the end of treatment, but some return of symptoms occurred by 6 months after treatment. The treatment was well accepted by patients. This study provides good preliminary evidence for the effectiveness of this intervention.     

Effect of pregnancy on resistance to Listeria monocytogenes and Toxoplasma gondii infections in mice.

Studies of the effect of pregnancy on the capacity of mice to resist Listeria monocytogenes and Toxoplasma gondii infection revealed significantly diminished resistance of pregnant mice to infection by both agents as measured by mortality. The development of immunity to listeria was assessed by studying the kinetics of listeria growth in the livers and spleens of virgin and pregnant mice infected intravenously with a sublethal dose of listeria. In both virgin and pregnant mice there was a rise in the number of listeria colony-forming units per organ during the first 3 days after infection. Thereafter, there was a decline in colony-forming units in these organs in virgin mice but a persistence of listeria in spleens and livers of pregnant mice. Paradoxically, during the first 3 days after infection, listeria counts in spleens of virgin mice were significantly higher than those in pregnant mice. Nonspecific resistance to listeria conferred by chronic infection with T. gondii was significantly diminished in pregnant mice when measured by mortality and quantitative cultures of listeria in livers and spleens. These studies demonstrate a remarkably decreased resistance of pregnant mice to two intracellular organisms and a diminished capacity of pregnant mice to develop immunity to listeria. This decrease in resistance may play an important role in congenital transmission of these organisms.     

Antigens of Toxoplasma gondii recognized by sera of AIDS patients before, during, and after clinically important infections

A longitudinal study of different parameters of the immune responses to Toxoplasma gondii was performed with sera of AIDS patients taken during and after clinically important Toxoplasma infections. Follow-up of patients lasted for 9 months on an average. The titres of the specific IgG and IgM antibodies were measured by an indirect fluorescent antibody test (IFAT), and the appearance of circulating antigens of Toxoplasma gondii was determined in 88 sera of 18 patients with CNS (6 cases), pulmonary (1), lymph-node toxoplasmosis (1), or asymptomatic primary infections (2), respectively. The profile of the IgG antibodies reacting with a lytic antigen originating from a pool of trophozoites of six different Toxoplasma strains were examined by means of an SDS-PAGE followed by an immunoblot. Although numerous antigen bands were recognized by the sera of patients with clinically important infections, an antigen pattern characteristic of an acute infection could not be discovered. The majority of these sera, however, recognized bands at 27 and 57 kd; proteins of these molecular weights are components of the circulating antigens. In patients without any indication of a Toxoplasma infection, small amounts of antibodies reacting with 34-38 kd antigens were detected. The results of this study demonstrate that seropositivity to Toxoplasma gondii in AIDS patients determined by routine serological methods (e.g. IFAT) may be very heterogeneous even if identical titres are found; it simply results from different combinations of various antibodies which can only be detected by the immunoblotting technique.     

Incidence of Toxoplasma gondii Infection in 35,940 Pregnant Women in Norway and Pregnancy Outcome for Infected Women

From 1992 to 1994 a screening program for detection of specific Toxoplasma gondii antibodies involving 35,940 pregnant women was conducted in Norway. For women with serological evidence of primary T. gondii infection, amniocentesis and antiparasitic treatment were offered. The amniotic fluid was examined for T. gondii by PCR and mouse inoculation to detect fetal infection. Infants of infected mothers had clinical and serological follow-up for at least 1 year to detect congenital infection. Of the women 10.9% were infected before the onset of pregnancy. Forty-seven women (0.17% among previously noninfected women) showed evidence of primary infection during pregnancy. The highest incidence was detected (i) among foreign women (0.60%), (ii) in the capital city of Oslo (0.46%), and (iii) in the first trimester (0.29%). Congenital infection was detected in 11 infants, giving a transmission rate of 23% overall, 13% in the first trimester, 29% in the second, and 50% in the third. During the 1-year follow-up period only one infant, born to an untreated mother, was found to be clinically affected (unilateral chorioretinitis and loss of vision). At the beginning of pregnancy 0.6% of the previously uninfected women were falsely identified as positive by the Platelia Toxo-IgM test, the percentage increasing to 1.3% at the end of pregnancy. Of the women infected prior to pregnancy 6.8% had persisting specific immunoglobulin M (IgM). A positive specific-IgM result had a low predictive value for identifying primary T. gondii infection.     

Postmortem findings and opportunistic infections in HIV-positive patients from a public hospital in Peru

There is a paucity of HIV autopsy data from South America and none that document the postmortem findings in patients with HIV/AIDS in Peru. The purpose of this autopsy study was to determine the spectrum of opportunistic infections and the causes of mortality in HIV-positive patients at a public hospital in Lima. Clinico-epidemiological information regarding HIV infection in Peru is also reviewed. Sixteen HIV-related hospital postmortems, performed between 1999 and 2004, were included in this retrospective analysis. The primary cause of death was established in 12 patients: one died of neoplasia and 11 of infectious diseases, including 3 from pulmonary infection, 7 from disseminated infection, and 2 from central nervous system infection (one case had dual pathology). Opportunistic infections were identified in 14 cases, comprising cytomegalovirus, histoplasmosis, cryptococcosis, toxoplasmosis, Pneumocystis pneumonia, aspergillosis, tuberculosis, varicella zoster virus, and cryptosporidiosis. Fourteen patients had at least one AIDS-related disease that had been neither clinically suspected nor diagnosed premortem. Moreover, 82% of the diagnoses considered to be of important clinical significance had not been suspected antemortem. The spectrum and frequency of certain opportunistic infections differed from other South American autopsy studies, highlighting the importance of performing HIV/AIDS postmortems in resource-limited countries where locally specific disease patterns may be observed.     

Role of NK cells and gamma interferon in transplacental passage of Toxoplasma gondii in a mouse model of primary infection

Protective immunity in mice infected with Toxoplasma gondii is mainly mediated by NK cells, CD4 and CD8 T cells, and type 1 cytokines, such as gamma interferon (IFN-gamma). To clarify the roles of NK cells and IFN-gamma in protection against primary congenital toxoplasmosis, we used recombination activating gene 2 knockout (RAG-2(-/-)) mice, which lack T and B lymphocytes, in comparison with the wild-type BALB/c model. RAG-2(-/-) mice had a significantly lower risk of fetal toxoplasmosis than BALB/c mice (25 versus 63.9%; P = 0.003). This protection was associated with an increased number of maternal NK cells, IFN-gamma secretion by spleen cells, and decreased parasitemia. In the RAG-2(-/-) mice, NK cell depletion increased both the rate of fetal infection, to 56.5% (P = 0.02), and the blood parasite burden. Conversely, in the BALB/c mice, this treatment did not modify maternofetal transmission or the blood parasite burden. Neutralization of IFN-gamma in both infected RAG-2(-/-) and BALB/c mice decreased congenital Toxoplasma transmission, contrasting with an exacerbation of maternal infection. These data suggest that a partially protective immunity against congenital toxoplasmosis is achieved due to the increased number of NK cells in RAG-2(-/-) mice. However, it seems that IFN-gamma enhances, directly or indirectly, the transplacental transmission.     

Efficacy and safety of discontinuing antibiotic treatment for uncomplicated respiratory tract infections when deemed unnecessary. A multicentre,randomized clinical trial in primary care

ObjectivesTo determine the benefits and harms of discontinuing unnecessary antibiotic therapy for uncomplicated respiratory tract infections (RTI) when antibiotics are considered no longer necessary.MethodsMulticentre, open-label, randomized controlled clinical trial in primary care centres from 2017 to 2020 (ClinicalTrials.gov, NCT02900820). Adults with RTIs—acute rhinosinusitis, sore throat, influenza or acute bronchitis—who had previously taken any dose of antibiotic for less than 3 days, which physicians no longer deemed necessary were recruited. The patients were randomly assigned in a 1:1 ratio to discontinuing antibiotic therapy or the usual strategy of continuing antibiotic treatment. The primary outcome was the duration of severe symptoms (number of days scoring 5 or 6 on a six-item Likert scale). Secondary outcomes included days with symptoms, moderate symptoms (scores of 3 or 4), antibiotics taken, adverse events, patient satisfaction and complications within the first 3 months.ResultsA total of 467 patients were randomized, out of which 409 were considered valid for the analysis. The mean (SD) duration of severe symptoms was 3.0 (1.5) days for the patients assigned to discontinuation and 2.8 (1.3) days for those allocated to the control group (mean difference 0.2 days; 95% CI –0.1 to 0.4 days). Patients randomized to the discontinuation group used fewer antibiotics after the baseline visit (52/207 (25.1%) versus 182/202 (90.1%); p 0.001). Patients assigned to antibiotic continuation presented a relative risk of adverse events of 1.47 (95% CI 0.80–2.71), but the need for further health-care contact in the following 3 months was slightly lower (RR 0.61; 95% CI 0.28–1.37).ConclusionsDiscontinuing antibiotic treatment for uncomplicated RTIs when clinicians consider it unnecessary is safe and notably reduces antibiotic consumption.