Nevin Turgay

Epidemiology, diagnosis and control of leishmaniasis in the Mediterranean region.

The leishmaniases are a widespread and medically important group of parasitic diseases, some of which pose a serious health threat in communities throughout the Mediterranean basin. In 1993, a joint, collaborative study of the Mediterranean leishmaniases was initiated by scientists from Israel, Turkey, Portugal and the Netherlands. The aim of this project was the development of a multi-component approach to the successful control of all forms of leishmaniasis, with special emphasis on the more severe, visceral leishmaniasis (VL). The need for highly sensitive and accurate new tools to facilitate diagnosis and epidemiological surveys of endemic areas and for studies on the immunology of VL in laboratory models (dogs and mice) was soon recognized. It is anticipated that the development of these tools and the associated technology will provide a better understanding of the disease and improve its control.

A survey on canine leishmaniasis in western Turkey by parasite, DNA and antibody detection assays.

Human visceral leishmaniasis (VL) caused by Leishmania infantum is found throughout the Mediterranean Region, including Turkey, where dogs are considered to be the main reservoir host for this parasite. In the district of Manisa, western Turkey, 37 human VL cases were reported from June 1993-August 1997. Twenty-four villages in this district were chosen for a survey of disease prevalence in dogs. The dogs, 490 in total, were examined using either the indirect immunofluoresence assay (IFAT) or direct agglutination test (DAT). Anti-Leishmania antibodies were found by at least one test in 5.3% (26/490) of the dogs. Infections were confirmed by parasitological examination of or polymerase chain reaction (PCR) on lymph node aspirates in 65% (13/20) and 76.4% (13/17) of the seropositive dogs tested, respectively. The confirmation rate was 85% by combining the results of PCR and microscopy. Our results demonstrate that canine VL is wide spread in western Turkey where human VL is endemic, and that serodiagnosis is a valuable tool for monitoring the infection.

Quantiferon-Leishmania as an Epidemiological Tool for Evaluating the Exposure to Leishmania Infection

The aim of the present preliminary study was to investigate the potential of measurement of IFN-γ secretion by T cells into blood plasma using QuantiFERON assay with leishmanial antigens to determine the presence of Leishmania infection. Blood samples from cured visceral (N = 18), and cutaneous (N = 20) leishmaniasis cases, and 20 healthy controls were tested. The IFN-γ responses to Leishmania major H2B and Leishmania infantum H2B antigens were detected from the majority of treated old visceral leishmaniasis cases, but not from controls. Future studies using larger groups will be required to establish the true potential of the assay for epidemiological screening of leishmaniasis.

Degree and frequency of inhibition in a routine real-time PCR detecting Pneumocystis jirovecii for the diagnosis of Pneumocystis pneumonia in Turkey.

Routine laboratory diagnosis of Pneumocystis jirovecii is currently achieved by PCR in almost all laboratories with sufficient equipment due to its high sensitivity and specificity compared to staining methods. A current issue that limits the reliability and sensitivity of PCR is the degree of inhibition caused by inhibitory substances in respiratory samples. The present study aimed to analyse the degree and frequency of inhibition in real-time PCR detecting P. jirovecii in respiratory specimens submitted to a Pneumocystis pneumonia (PcP) diagnosis laboratory in Ege University Medical School, Turkey. Between July 2009 and December 2010, 76 respiratory specimens [63 bronchoalveolar lavage (BAL) fluid, 10 sputum samples, two tracheal aspiration fluid and one thoracentesis fluid] obtained from 69 PcP-suspected patients were investigated for the presence of P. jirovecii using real-time PCR targeting the cdc2 gene. Of these samples, 42 of the specimens were stained and examined by microscopy according to the request of the clinicians. PCR was positive in 15 specimens in the initial run. Of the remaining 61 samples, 41 of them were negative with positive internal inhibition controls (i.e. true-negative group). The frequency of inhibition in the initial run was 26.31 % (20/76) as determined by spiked negative controls. All of the inhibited samples were resolved after 1 : 2, 1 : 5, 1 : 10 and 1 : 20 dilutions. P. jirovecii was detected by PCR in two inhibited specimens after retesting with diluted samples which were also positive by microscopy. The incidence of P. jirovecii in respiratory specimens was 22.36 % (17/76) as determined by real-time PCR and 7.14 % (3/42) by microscopy. Overall, the incidence of P. jirovecii in respiratory samples was 23.68 % (18/76) as detected by both methods. In conclusion, inclusion of spiked positive controls in each sample and retesting with diluted samples to resolve inhibition increased the reliability of the real-time PCR assay in terms of determining false-negative results and influencing the treatment of the patient. Furthermore, results of the present study determined for the first time the frequency and degree of inhibition in a real-time PCR detecting P. jirovecii in respiratory specimens during routine diagnosis of PcP.

Differentiation of Entamoeba histolytica/Entamoeba dispar by the polymerase chain reaction in stool samples of patients with gastrointestinal symptoms in the Sanliurfa Province.

OBJECTIVE We aimed to diagnose amebiasis and also identify Entamoeba histolytica (E. histolytica) and Entamoeba dispar (E. dispar) in patients with gastrointestinal symptoms in an endemic region in Turkey. METHODS Stool samples obtained from 181 patients with gastrointestinal symptoms from the Harran University Hospital of Sanliurfa were examined for the diagnosis of amebiasis by the three methods which are as follows:- In house polymerase chain reaction (PCR) targeting the 135 base pair region located on the small-subunit ribosomal RNA (SSU rRNA) gene to differentiate E. histolytica from E. dispar; and the commercial kit, RIDASCREEN® stool ELISA, that identifies Entamoeba sensu lato antigen and microscopical examination of Trichrome stained smears of stool samples. RESULTS Positivity for E. histolytica/E. dispar complex was found to be 79 (43.6%) by microscopy versus 83 (45.9%) by PCR out of 181 stool samples. A total of 45 patients were found to be positive by the antigen detection method. PCR and microscopy were both positive in 59 samples. The number of patients infected with E. dispar (39.8%) was found to be higher than E. histolytica (3.3%) while 5 patients (2.8%) had mixed E. histolytica+E. dispar infections according to PCR results. CONCLUSION Routine diagnosis of amebiasis by a combination of microscopy and antigen detection technique should be complemented with a PCR assay as a reference test for sensitive differentiation of both species.

[Monthly distribution of intestinal parasites detected in a part of western Turkey between May 2009-April 2010-results of acid fast and modified trichrome staining methods].

OBJECTIVE In this study, 5073 fecal specimens and cellophane tapes from patients were examined during the period of May 1, 2009-April 30, 2010 in the parasitology laboratory of the Ege University Medical School. METHODS Sticky tape test and ethyl acetate sedimentation methods, saline, iodine, modified kinyouns acid-fast, Trichrome, modified Trichrome and giemsa staining procedures have been applied to the stool samples. RESULTS After the macroscopic and microscopic examinations, 1138 (22.43%) intestinal parasites were determined. Cryptosporidium spp. (n=381; 33.47%), Blastocystis hominis (n=368; 32.33%) and Cyclospora spp. (n=187; 16.43%) were the three most common parasites obtained during the examination. The most commonly determined helminth was Enterobius vermicularis (n=33; 2.89%). CONCLUSION Detection of Microsporidium spores in immununosuppressed patients showed also the importance of specific staining methods. Intestinal parasites are causing serious public health problems in our region.

Health and Illness as a State of Being Human

A definition of complete well-being is a certain level of being physically, mentally, and socially healthy. Cultural and social variables have had strong influences on health and illness concepts throughout the history. Our aim here is to describe the changes in relation to these issues from the very ancient times. These developments are followed by the factors from our era, influencing modern determinants on the persistence of state of being comfortable, healthy, and happy.

Glia Hücrelerinin Antimona Dirençli Leishmania tropica ile Enfekte Edilmesi: Yeni Bir ex-vivo Modeli

Leishmaniasis is a vector-borne zoonotic disease that shows different clinical features like cutaneous, mucocutaneous, visceral and viscerotropic forms. The protocols used in the treatment of leishmaniasis are toxic and have many limitations during administration. One of the limitations of treatment is the resistance against the protocols in practice. There is also a need to define new treatment options especially for resistant patients. Ex-vivo models using primary cell cultures may be a good source for evaluating new drug options in patients with antimony resistance, in addition to in-vitro and in-vivo studies. In this study, it was aimed to define a new ex-vivo culture model to evaluate treatment options in patients with cutaneous leishmaniasis who did not respond to treatment. In our experimental model of ex-vivo infection, Leishmania tropica promastigotes isolated from a case previously diagnosed with cutaneous leishmaniasis were used. The primary astroglial cell culture used for the ex-vivo model was prepared from 2-3 days old neonatal Sprague Dawley rat brains under sterile conditions by the modification McCarthys method. The astroglia cells, which reached sufficient density, were infected with antimony resistant L.tropica promastigotes. After 24 hours of incubation, the supernatant on the cells were collected, the cell culture plate was dried at room temperature, then fixed with methyl alcohol and stained with Giemsa to search for L.tropica amastigotes. Amastigotes were intensely observed in glia cells in primary cell cultures infected with L.tropica promastigotes. No promastigotes were seen on Giemsa stained preparations of the precipitates prepared from the bottom sediment after the centrifugation of the liquid medium removed from the infected plates. In this study, promastigotes from a cutaneous leishmaniasis patient unable to respond to pentavalent antimony therapy were shown to infect rat glia cells and converted to amastigote form. This amastigote glial cell model, as far as we know, is the first model in the literature produced by L.tropica. The occurrence of L.tropica amastigote forms in glia cells may be indicative of the ability of Leishmania species to infect the central nervous system. The central nervous system may be an area for the Leishmania amastigotes to escape from the immune system in cases of leishmaniasis without a treatment response. Our study is important because it is the first study to show the infection of glia cells with L.tropica amastigotes.

Fever of Unknown Origin and Visceral Leishmaniasis: a Series of 20 Adult Patients

Visceral Leishmaniasis (VL) is a parasitic disease frequently seen in Mediterranean countries, including our country, which still constitute a major public health problem. In this study, it was aimed to investigated retrospectively 20 cases diagnosed with visceral leishmaniasis (VL) among the cases referred from different clinics/centers for further examination to our department due to fever of unknown origin in terms of demographic characteristics, underlying diseases, laboratory, clinical data and treatment results between 2007-2017. Adults with chronic systemic diseases are always at risk in endemic regions and VL should be considered in differential diagnosis, particularly in cases of fever of unknown origin.

The association between Cytomegalovirus co-infection with Pneumocystis pneumonia and mortality in immunocompromised non-HIV patients

Impact of Cytomegalovirus (CMV) co‐infection pneumonia in non‐HIV patients with Pneumocystis jirovecii pneumonia (PCP) is unclear.