Performance evaluation of different strategies based on microscopy techniques, rapid diagnostic test and molecular loop-mediated isothermal amplification assay for the diagnosis of imported malaria.

OBJECTIVES: Malaria is one of most common tropical diseases encountered in travellers and migrants. It requires an urgent and reliable diagnosis considering its potential severity. In this study, performance of five diagnostic assays were evaluated in a nonendemic region and compared prospectively to quantitative PCR (qPCR). METHODS: A prospective study was conducted at Toulouse Hospital from August 2017 to January 2018 and included all patients with initial Plasmodium screening. Thin and thick blood smears (TnS, TkS), quantitative buffy coat (QBC), rapid diagnostic tests (RDTs) and commercial loop-mediated isothermal amplification (LAMP) were independently performed on each blood sample and compared to our qPCR reference standard. RESULTS: The study encompassed 331 patients, mainly returning from Africa. qPCR detected 73 Plasmodium-positive samples (including 58 falciparum). Individually, LAMP had a 97.3% (71/73) sensitivity, far ahead of TnS (84.9%, 62/73), TkS (86.3%, 63/73), QBC (86.3%, 63/73) and RDT (86.3%, 63/73). RDT demonstrated a high sensitivity for falciparum (98.3%, 57/58) but missed all ovale, malariae and knowlesi infections. Specificity was excellent for all techniques (99.6-100%). The most sensitive diagnosis strategies were TnS + RDT (95.9%, 70/73), TnS + LAMP (97.3%, 71/73) and TnS + RDT + LAMP (100%, 73/73), about 10% higher than strategies using exclusively microscopy, TkS + TnS (87.7%, 64/73) or QBC + TnS (87.7%, 64/73). TnS remains necessary for Plasmodium species identification and quantification. Adding sequentially TnS only on LAMP-positive samples did not decrease TnS + LAMP strategy sensitivity. CONCLUSIONS: In nonendemic countries, the currently recommended microscopy-based strategies seem unsatisfactory for malaria diagnosis considering RDT and LAMP performance, two rapid and sensitive assays that require limited training.

Large outbreak of urogenital schistosomiasis acquired in Southern Corsica, France: monitoring early signs of endemicization?

OBJECTIVES: Clustered cases of urogenital schistosomiasis were reported in April 2014 among French and German tourists linked to exposure in the Cavu River, Southern Corsica, France, between 2011 and 2013. We set up national surveillance for autochthonous urogenital schistosomiasis to document the largest possible number of cases in order to identify potential sites of transmission and to determine the extent of the outbreak in France and Corsica. METHODS: The early response consisted mostly of prohibiting swimming in the river, performing a nationwide serologic screening of all persons exposed to the river between 2011 and 2013 and treating confirmed cases. Physicians were asked to report all patients with one or more positive antischistosome serologic test. Cases were defined as occurring in a resident of France with serologic evidence of schistosomiasis or schistosome eggs in urine and no history of contact with freshwater in known endemic areas. We documented symptoms as well as place and time of exposure to freshwater for all subjects. To estimate the outbreak size, we modelled the effect of the 2014 nationwide screening on the 2011-2015 time series of serodiagnosed schistosomiasis cases using log-linear autoregression. RESULTS: In 2014, a total of 106 autochthonous cases were reported, including 35 symptomatic infections. All patients had swum in the Cavu during summer 2013. Over 30 000 persons were likely screened for autochthonous schistosomiasis. The model-estimated outbreak size was 338 cases, including 36 serodiagnosed in 2015. CONCLUSIONS: Besides the 2013 outbreak, there is evidence of small-scale transmission in 2015 in Corsica. Early detection and control of recurrences requires raising community and medical awareness.

[Urinary schistosomiasis and cancer]. / Schistosomose urogénitale et cancer.

The existence of a link between urinary schistosomiasis (US) and bladder carcinoma was first suspected by C. Goebel in 1905. In 1911, A.R Ferguson, who was a professor of Pathology and Microbiology at the Faculty of Medicine in Cairo, published a more detailed survey from 40 autopsies, and reported a likely association of bladder carcinoma with granulomas caused by US. Subsequently, published results from several studies reinforced Ferguson's hypothesis. Moreover, in most countries where US was endemic, association of high prevalence of bladder carcinoma with US had been pointed out. A further circumstantial evidence was a higher prevalence of bladder squamous cell carcinoma in areas endemic for SU, whereas urothelial carcinomas were more prevalent in areas which were free of SU. However, evidence of a positive correlation between SU and bladder carcinoma was delivered only many decades later, following the results from case-control studies which were adjusted on age, sex, type of dwelling and tobacco consumption. During SU, the mechanisms underlying the onset of bladder carcinoma are still poorly understood due to the lack of any convenient animal model. Classically, two processes are thought to be involved. Chronic inflammation inside bladder would be caused by granulomas centered by eggs, and would result in a neoplasmic evolution, after years. Moreover, alteration of the bladder dynamics would elicit urine stasis which in turn would cause repeated infection of bacterial or viral origin. Beside the high prevalence of squamous cell type, the natural history of bladder carcinomas caused by SU is similar to that of other malignant tumors of the bladder. Also the treatment and prognosis are identical. Albeit genital involvement is very frequent during SU, Schistosoma haematobium does not appear to be a cause of cancers of genital organs. Schistosoma mansoni and S. japonicum have been suspected to be associated with liver or colic carcinomas, but epidemiological studies have not yielded any firm evidence so far. The entire sequencing of S. haematobium genome, along with the recent availability of a more efficient mouse model, must provide a better understanding of the genesis of bladder carcinomas during SU. However, the key for a sharp decrease in both morbidity and mortality due to SU-linked carcinomas lies in a better control of haematobium schistosomiasis, such as observed in Egypt since 1970.

Risk factors of Pneumocystis pneumonia in solid organ recipients in the era of the common use of posttransplantation prophylaxis.

Pneumocystis pneumonia (PCP) in solid organ transplant (SOT) recipients becomes rare in the immediate posttransplantation period thanks to generalized prophylaxis. We aimed to identify the predictive factors for PCP in the era of universal prophylaxis and to propose a strategy for preventing PCP beyond the first year after transplantation. In a retrospective case-control study, 33 SOT cases with PCP diagnosed between 2004 and 2010 were matched with two controls each to identify risk factors for PCP by uni- and multivariate analysis. All the patients benefited from 6 months of posttransplantation trimethoprim-sulfamethoxazole prophylaxis. Most PCP in SOT patients occurred during the second year posttransplantation (33%). By univariate analysis, age, nonuse of tacrolimus, total and CD4 lymphocyte counts, gamma-globulin concentration and cytomegalovirus (CMV) infection appeared to be PCP risk factors. In the final multivariate analysis, age (adjusted odds ratio [OR] 3.7, 95% confidence interval [CI]: 1.3-10.4), CMV infection (OR: 5.2, 95% CI: 1.8-14.7) and total lymphocyte count (OR: 3.9, 95% CI: 1.4-10.7) were found to be independently associated with PCP. The second year posttransplantation appeared to be the new period of highest risk of PCP. Age, CMV viremia and lymphocytes were the most pertinent predictive criteria to evaluate the risk of PCP in clinical practice.

Contribution of molecular diagnosis to the management of cutaneous leishmaniasis in travellers.

Cutaneous leishmaniasis is one of the most frequent skin diseases occurring after travelling in endemic areas. Optimal management requires identification of the species of Leishmania involved. In this study we aimed to evaluate the use of molecular diagnosis as routine, in comparison with direct examination and culture. Thirty positive diagnoses were carried out between 2007 and 2013. Classical PCR enabled 11 positive cases to be identified that were found to be negative by conventional methods. Sequencing led to the identification of eight different species. Routine use of PCR and sequencing appears very efficient in the management of cutaneous leishmaniasis.

Laboratory diagnosis of human toxocariasis.

Toxocariasis is a helminth zoonosis caused by infection with the larvae of Toxocara spp. ascarid worms. Only two species, Toxocara canis and Toxocara cati, are recognised as causative agents of human disease. The best choice for serodiagnosis of the generalised forms of toxocariasis, visceral larva migrans (VLM) or covert toxocariasis, relies upon the initial use of TES-ELISA, after which any positive result should subsequently be tested by Western blotting (WB). Covert toxocariasis is mostly a benign infection, so a large majority of infected subjects are asymptomatic or have very few symptoms and therefore go undiagnosed. In this form, this helminthosis is often self-limiting, leaving residual specific antibodies. A positive serodiagnosis caused by residual antibodies that do not have any diagnostic significance can be associated with any infectious or non-infectious disease. If separated from the ongoing clinical and laboratory context, such a positive result has no diagnostic value and should be only taken into account after the possible etiologies of any observed syndromes have been ruled out. Unlike the methods used for the immunodiagnosis of bacterial, viral or protozoal (toxoplasmosis) infections, it is not possible with toxocariasis to assess the age of the presence of specific IgG using the levels of specific IgM because IgM antibodies can be found throughout the course of helminthiasis. The detection of other classes of immunoglobulins, namely IgE and IgA, the subclasses, namely IgG4 or circulating Ag was proven to be unable to discriminate between active and self-cured generalised toxocaral infections. Currently, the diagnosis of an active covert toxocariasis relies upon indirect arguments, e.g., the presence of otherwise unexplained symptoms along with blood eosinophilia and/or elevated levels of eosinophil cationic protein (ECP). This situation is far from ideal and more research should be carried out to solve this difficult problem.

Simultaneous cutaneous infection due to Paecilomyces lilacinus and Alternaria in a heart transplant patient.

Paecilomyces lilacinus is an emerging pathogen in immunocompromised patients. We report here a case of cutaneous hyphomycosis in a 63-year-old heart transplant recipient caused by the simultaneous presence of 2 molds: Paecilomyces lilacinus and Alternaria alternata. The infection was successfully treated with local voriconazole followed by oral terbinafine.

Antimalarial activity of simalikalactone E, a new quassinoid from Quassia amara L. (Simaroubaceae).

We report the isolation and identification of a new quassinoid named simalikalactone E (SkE), extracted from a widely used Amazonian antimalarial remedy made out of Quassia amara L. (Simaroubaceae) leaves. This new molecule inhibited the growth of Plasmodium falciparum cultured in vitro by 50%, in the concentration range from 24 to 68 nM, independently of the strain sensitivity to chloroquine. We also showed that this compound was able to decrease gametocytemia with a 50% inhibitory concentration sevenfold lower than that of primaquine. SkE was found to be less toxic than simalikalactone D (SkD), another antimalarial quassinoid from Q. amara, and its cytotoxicity on mammalian cells was dependent on the cell line, displaying a good selectivity index when tested on nontumorogenic cells. In vivo, SkE inhibited murine malaria growth of Plasmodium vinckei petteri by 50% at 1 and 0.5 mg/kg of body weight/day, by the oral or intraperitoneal routes, respectively. The contribution of quassinoids as a source of antimalarial molecules needs therefore to be reconsidered.

Diagnosis of congenital toxoplasmosis: prenatal and neonatal evaluation of methods used in Toulouse University Hospital and incidence of congenital toxoplasmosis.

The aim of this study was to determine the incidence of congenital toxoplasmosis (CT) and to assess the performances of prenatal and neonatal diagnoses. From 1994-2005, in Toulouse University Hospital, France, amniocentesis was performed on 352 pregnant women who were infected during pregnancy. All women were treated with spiramycin and pyrimethamine-sulfadoxine when prenatal diagnosis was positive. Among the 275 foetuses with follow-up, 66 (24%) were infected. The transmission rates of Toxoplasma gondii were 7%, 24% and 59% in the first, second and third trimesters, respectively. The sensitivity and specificity of PCR on amniotic fluid (AF) were 91% and 99.5%, respectively. One case was diagnosed by mouse inoculation with AF and six cases were diagnosed by neonatal or postnatal screening. The sensitivity and specificity of PCR on placentas were 52% and 99%, respectively. The sensitivity of tests for the detection of specific IgA and IgM in cord blood was 53% and 64%, respectively, and specificity values were 91% and 92%. In conclusion, PCR performed on AF had the highest levels of sensitivity and specificity for the diagnosis of CT. This permits an early diagnosis of most cases and should be recommended.

Diagnosis of congenital toxoplasmosis: prenatal and neonatal evaluation of methods used in Toulouse University Hospital and incidence of congenital toxoplasmosis

The aim of this study was to determine the incidence of congenital toxoplasmosis (CT) and to assess the performances of prenatal and neonatal diagnoses. From 1994-2005, in Toulouse University Hospital, France, amniocentesis was performed on 352 pregnant women who were infected during pregnancy. All women were treated with spiramycin and pyrimethamine-sulfadoxine when prenatal diagnosis was positive. Among the 275 foetuses with follow-up, 66 (24 percent) were infected. The transmission rates of Toxoplasma gondii were 7 percent, 24 percent and 59 percent in the first, second and third trimesters, respectively. The sensitivity and specificity of PCR on amniotic fluid (AF) were 91 percent and 99.5 percent, respectively. One case was diagnosed by mouse inoculation with AF and six cases were diagnosed by neonatal or postnatal screening. The sensitivity and specificity of PCR on placentas were 52 percent and 99 percent, respectively. The sensitivity of tests for the detection of specific IgA and IgM in cord blood was 53 percent and 64 percent, respectively, and specificity values were 91 percent and 92 percent. In conclusion, PCR performed on AF had the highest levels of sensitivity and specificity for the diagnosis of CT. This permits an early diagnosis of most cases and should be recommended.

Predictive factors of treatment interruption duration in a cohort of HIV-1 infected patients with CD4 count greater than 350 cells per mm3.

OBJECTIVE: To determine predictive factors of treatment interruption (TI) duration within a cohort of HIV-1 infected patients having stopped their treatment with CD4 above 350 cells per mm(3). DESIGN: Data were collected from computerized medical records. Patients were selected if they were HIV-1 positive, 18 years of age or older, and had stopped their treatment between January 1st, 1999 and July 1st, 2003, with CD4 count above 350 cells per mm(3). The study period was censored on October 1st, 2003. Patients were assessed every 3 months from inclusion to censure. A survival analysis using the Cox proportional hazard model was performed. RESULTS: One hundred eighty-five patients were included. The median duration of TI was 43 weeks. Sixty-three patients remained off-treatment at censure. In the multivariate analysis, TI duration was shorter if CD4 nadir was below 250 cells per mm(3) before TI (relative hazard, 2.10), age superior to 40 (relative hazard, 1.72), viral load higher than 2.3 log.copies per ml (relative hazard, 1.52), and CDC class C (relative hazard, 1.78) at TI. Neither CD4 cell count at TI, numbers of treatments, nor duration of treatment and infection before TI were independent predictive factors of early treatment resumption (TR). CONCLUSION: Some clinical and biological data may be used as predictive factors of early TR. Our results can have implications on future therapeutic strategies, in which the goal of therapy is to maintain CD4 cell count above a predetermined threshold using cycles of therapy followed by prolonged interruption according to CD4 count.

[Retinal detachment by inferior tear: a poor prognosis?]. / Décollement de rétine par déchirure inférieure, facteur de mauvais pronostic?

AIM: To determine whether a lower location of retinal wounds is a factor for poor prognosis in retinal detachment. PATIENTS AND METHOD: This retrospective study involved 248 medical records of patients who were operated on for retinal detachment in 2001 at the Toulouse-Rangueil Hospital Ophthalmology Department. We excluded retinal detachment of very short-sighted patients, diabetic patients and detachment secondary to trauma or relapses. We compared the incidence of surgical failure according to various parameters: condition of the crystalline lens, operative technique, operator, vitreoretinal proliferation, retinal wound location, patient age and the operative side. Thirty-six patients presented with lower wounds; 17 patients obtained incomplete results and relapsed within 1 year of surgery. RESULTS: Vitreoretinal proliferation and inferior location of the retinal detachment were found to be poor prognostic factors. No significant differences were found between the other parameters studied. DISCUSSION: A variety of prognostic factors of retinal detachment surgery are now clearly identified (vitreoretinal proliferation, old detachment). A lower location of the detachment constitutes an additional difficulty for retinal applications. Indeed, it is more difficult to perform effective buffering in this type of case. We recommend that retinal detachment be operated internally, to reduce the risk of relapse. CONCLUSION: An inferior location of the retinal wound during retinal detachment appears to be a factor of poor prognosis, but this remains to be ascertained through an ongoing, prospective study.

[Management of occupational and sexual exposure to HIV in the Toulouse teaching hospital]. / Prise en charge des accidents d'exposition au VIH d'origine professionnelle et sexuelle: etat des lieux au centre hospitalo-universitaire de Toulouse.

OBJECTIVE: This study had aim to describe the management of occupational and sexual HIV exposure in the Toulouse teaching hospital. DESIGN: A prospective descriptive study was made of patients reporting with potential HIV exposure in Toulouse between 01/01/2000 and 12/31/2002. RESULTS: Six hundred and ninety three cases were reported, 236 after occupational and, 457 after sexual exposure. The frequency of sexual exposures increased with time. 61.2% of patients received post-exposure treatment and no seroconversion was diagnosed during their follow-up. Eighty-four percent of treated patients received three anti-retroviral drugs, with a protease inhibitor in 57%. Treatment was more frequently prescribed in sexual exposures than in occupational ones. For occupational exposures, the median time between exposure and consultation was 4 h and was decreased by spontaneous bleeding but not affected by source patient serostatus or injury deepness. Treatment was more frequent when injury was deep, when there was spontaneously bleeding, and when the source patient serostatus was positive or unknown. For sexual exposures, the median time between exposure and consultation was significantly superior to 4 h. That was diminished by positive source person serostatus but not affected by the partner's gender, nature of intercourse, or rape. Treatment was more frequently prescribed in case of positive or unknown source person serostatus, rape and homosexual intercourse. CONCLUSIONS: Given the delay before consultation for sexual exposures and out of delay treatment in occupational exposures, discussion with health professionals on implementing procedures and means seems mandatory.

Hydrocarbons in surface sediments from the Changjiang (Yangtze River) Estuary, East China Sea.

Sedimentary aliphatic (AH) and polycyclic aromatic hydrocarbons (PAHs) were studied in the Changjiang Estuary and the adjacent East China Sea. Total AH ranged from 2.20 to 11.82 microg g(-1) and consisted of n-alkanes and a dominant petroleum-related unresolved complex mixture (UCM). Within the n-alkanes, terrestrial plant wax compounds prevailed at nearly all stations. Of the PAHs, biogenic perylene dominated at stations receiving riverine inputs. Anthropogenic PAHs originating from combustion/pyrolysis processes varied from 17 to 157 ng g(-1), while fossil PAH concentrations ranged from 42 to 187 ng g(-1). Both biogenic and anthropogenic hydrocarbons are primarily derived from riverine discharges and accumulate at shallow-water stations. Distinct phase associations lead, nevertheless, to different sedimentation patterns. Fossil PAHs are enhanced at offshore stations where they are introduced directly by shipping activities. Biomarker fingerprints ascribe their source to Chinese crude oils. The overall levels of anthropogenic hydrocarbons are low compared to relevant areas worldwide and reveal a low/moderate level of hydrocarbon pollution.