Retrospective Results of Hacettepe University Faculty of Medicine Parasitology Laboratory Between 2014-2019

Objective: Parasitic infections emerge as a significant health problem, especially in underdeveloped and developing countries. Epidemiological data play an important role in taking effective measures against parasitic diseases. Methods: Clinical samples (stool, blood, bone marrow and tissue samples, etc.) that were sent to Hacettepe University Hospitals Parasitology Laboratory between 2014 and 2019 were analyzed retrospectively. Results: The positivity rates of the parasites detected in this study are as follows; Blastocystis sp. (71.6%), Dientamoeba fragilis (13.3%), Giardia lamblia (4.7%), Echinococcus spp. (1.9%), Enterobius vermicularis (1.8%) and Taenia spp. (0.3%). In this study, four of the patients were found to be positive for Leishmania spp. and two patients for Plasmodium falciparum and four patients for Plasmodium spp. E. histolytica/E. dispar cysts and/or trophozoites examined by Trichrome staining in our study were not detected within six years. Conclusion: According to this data and in the light of the results obtained from different regions of our country, it will be possible to properly direct the necessary strategies for the diagnosis, treatment of parasitic infections and the implementation of preventive measures.

Investigation of Dientamoeba fragilis and Blastocystis in patients from Turkey with ulcerative colitis and irritable bowel syndrome: Any relation with genotypes?

Blastocystis sp. and Dientamoeba fragilis are two most common protists worldwide, whose pathogenic potentials are a matter of debate since their discovery. This study aims to investigate the relationship between the activation of ulcerative colitis (UC) and irritable bowel syndrome (IBS) with these protists. A total of 100 patients (35 IBS, 35 active UC, and 30 remittent UC), diagnosed at Hacettepe University Adult Hospital (Ankara, Turkey), were screened for D. fragilis and Blastocystis sp. with microscopic examination using the methods of wet mount, trichrome staining, conventional PCR, nested PCR, real-time PCR and genotyping. Eight patients (4 IBS, 2 active, and 2 remittent UC patients) were found to be D. fragilis positive. 18S rRNA region of the parasite was amplified in four of the patients, whereas cathepsin L-like cysteine peptidase; clan Sc, family S9, serine peptidase; and clan MH, family M20 metallopeptidase in six different patients. All isolates were Genotype 1. Sequence results showed very limited diversity. A total of nine patients (3 IBS, 5 active UC, 1 remittent UC) were found to be positive for Blastocystis sp., all of which were Subtype 3. One active UC and one IBS patient were found to be positive for both parasites. No statistically significant difference was detected between the patient groups in means of parasite detection. D. fragilis was found to be related to older age (p=0,045). In our study, no significant correlation was identified between D. fragilis and Blastocystis sp., and the activation of UC and IBS. More studies are needed on the host-parasite relationship, including the role of gut microbiota, together with transcriptomic and metabolomic assessments to unveil the pathogenicity of both protists.

Cystoisospora belli infection in a renal transplant recipient: a case report and review of literature.

Cystoisospora belli is a coccidian parasite that causes prolonged watery diarrhea especially among immunocompromised patients. Herein, we report a renal transplant patient who complaints of alternating diarrhea and review of literature related to cystoisosporiasis amongst the transplant recipients.

Investigation of Intestinal Protozoon Prevalence in Immunocompromised Patients at a University Hospital

Objective: Immunocompromised patients are at a greater risk of developing intestinal parasite infections. In this study, we examined the presence of Enterocytozoon bieneusi, Encaphalitozoon intestinalis and other intestinal protozoa in stool samples of immunosuppressed patients. Methods: A total of 100 stool samples were obtained from patients receiving chemotherapy because of solid organ tumour with haematological malignancies and those receiving immunosuppressive treatment because of rheumatic diseases, organ transplant patients and patients receiving treatment for HIV-related infections. Stool samples were examined by using the native-lugol method in which the stool concentration, modified Kinyoun acid-fast and trichrome staining methods and parasite presence were analysed. The stool samples were also examined for the presence of Enterocytozoon bieneusi and Encephalitozoon intestinalis using an indirect fluorescent antibody method. Results: Intestinal parasites were detected in 12% of all patients. The distribution of intestinal parasites in patients were 7% Blastocystis spp., 2% Blastocystis spp. + Dientamoeba fragilis, 1% Blastocystis spp. + Entamoeba coli, 1% Blastocystis spp. + Giardia intestinalis and 1% G. intestinalis. Microsporidia spp. were detected in 4% of all patients by the IFAT method and in 8% of all patients by calcoflour staining method. Conclusion: In our study, the most prevalent parasite detected in the immunosuppressed patients was Blastocystis spp. The pathogenesis of Blastocystis spp. remains to be controversial, and their role in immunocompromised patients continues to remain unknown. Although these rates detected in our study are similar to the prevalence in the normal population, it is important to study these microorganisms in immunocompromised patients in terms of the associated decreasing morbidity and mortality rates.

The investigation of Strongyloides stercoralis seroprevalence in immunosupressed patients in Turkey

Background/aim: In immunosuppressed patients, strongyloidiasis can be lifethreatening because of hyperinfection or dissemination. Therefore, diagnosis of S. stercoralis is important in immunosuppressed patients with chronic strongyloidiasis. In this study, our objective was to investigate the presence of S. stercoralis antibodies by an ELISA method in immunosuppressed patients. Materials and methods: A total of 100 immunosuppressed patients' sera were included in the study. Forty-two of the patients were receiving immunosuppressive therapies for cancer or being treated for hematopoietic malignancies, 38 of the patients were receiving immunosuppressive drugs for rheumatic diseases, 14 were receiving immunosuppressive therapies for liver transplantation. Two of the patients were being treated for HIV infection and 4 were being treated for hypogammaglobulinemia. As control group, 50 individuals without a known disease were included in the study. The presence of IgG antibodies against S. stercoralis was investigated with a commercial ELISA kit. Results: S. stercoralis antibody test was positive in 4 of 100 (4%) sera from immunosuppressed patients. All control patients were negative for S. stercoralis. Conclusions: Strongyloidiasis can be a lifelong chronic infection if not treated. In patients who are going to receive immunosuppressive therapy, it should be tested before treatment, as it can become a disseminated and life-threatening infectious disease.

Refractory Giardiasis in an Immunosuppressed Patient in Turkey.

Giardiasis is an infection of the small intestine caused by the protozoan parasite Giardia duodenalis. In immunocompetent patients the infection is usually self-limited and no treatment may be needed. Immunodeficiency, however, is a predisposing factor for the development of severe Giardia infection. In this report, a case of recurrent giardiasis refractory to nitroimidazoles and nitazoxanides presented. A 28-year-old male patient with hypogammaglobulinemia admitted to our hospital because of chronic diarrhoea. Microscopic examination of stool revealed a high number of Giardia trophozoites and cysts. Treatment with higher doses and a longer course of metronidazole, trimethoprim-sulfamethoxazole, ornidazole and albendazole failed. Administration of nitazoxanide, which has been reported to be effective against Giardia duodenalis refractory to nitroimidazoles, was commenced, but his symptoms persisted and stool samples demonstrated Giardia trophozoites and cysts again.

A Case of Extensive Wound Myiasis Caused by Lucilia sericata (Diptera: Calliphoridae) in a Patient with Maxillary Sinus Squamous Cell Carcinoma, in Turkey.

The larvae causing myiasis can lead extensive tissue destruction, invasion into deep tissues and secondary infections. Poor hygiene, low socioeconomic condition and presence of open wounds are the most important predisposing factors. This case report describes destructive wound myiasis in a 58-year-old male patient diagnosed with maxillary sinus squamous cell carcinoma who lives in a rural area in Ankara, Turkey. Approximately 200 larvae were collected and identified as Lucilia sericata by morphological examination. Myiasis should be considered especially when the patient has open extensive lesions such as malignant wounds.

Compartment-specific remodeling of splenic micro-architecture during experimental visceral leishmaniasis.

Progressive splenomegaly is a hallmark of visceral leishmaniasis in humans, canids, and rodents. In experimental murine visceral leishmaniasis, splenomegaly is accompanied by pronounced changes in microarchitecture, including expansion of the red pulp vascular system, neovascularization of the white pulp, and remodeling of the stromal cell populations that define the B-cell and T-cell compartments. Here, we show that Ly6C/G(+) (Gr-1(+)) cells, including neutrophils and inflammatory monocytes, accumulate in the splenic red pulp during infection. Cell depletion using monoclonal antibody against either Ly6C/G(+) (Gr-1; RB6) or Ly6G(+) (1A8) cells increased parasite burden. In contrast, depletion of Ly6C/G(+) cells, but not Ly6G(+) cells, halted the progressive remodeling of Meca-32(+) and CD31(+) red pulp vasculature. Strikingly, neither treatment affected white pulp neovascularization or the remodeling of the fibroblastic reticular cell and follicular dendritic cell networks. These findings demonstrate a previously unrecognized compartment-dependent selectivity to the process of splenic vascular remodeling during experimental murine visceral leishmaniasis, attributable to Ly6C(+) inflammatory monocytes.

[Molecular typing of clinical Candida krusei isolates by using restriction endonuclease analysis of genomic DNA and polymerase chain reaction]. / Candida krusei klinik izolatlarinin genomik DNA restriksiyon enzim analizi ve polimeraz zincir reaksiyonu ile tiplendirilmesi.

Candida krusei is inherently resistant to fluconazole and is an important pathogen responsible for nosocomial candidiasis especially in patients with hematological malignancy. Despite the growing clinical importance of C. krusei infections, little is known of its genetic diversity and molecular epidemiology. Therefore, differentiating between C. krusei isolates is of importance for a better understanding of the epidemiology, mode of transmission and pathogenesis of the organism. We investigated the use of two different methods (restriction endonuclease analysis of genomic DNA (REAG) with Hinfl and polymerase chain reaction by using Arno1 and Arno2 primers) for molecular typing of 56 C. krusei isolates from 56 patients. Ten different types (A-J) were determined by REAG. Depending on the patterns of isolates, the number of the bands varied from 12 to 15 and the size of the fragments varied from 2.0 kb to 6.2 kb. Of the isolates 71.4% were gathered under three major patterns (D, F, H). In the second method, PCR amplified different sizes of fragments varied approximately from 1 kb to 2 kb, which yielded 13 types (a-m) from 56 patients. Four major patterns (d, f, h, k) were observed for 58.9% of the isolates. The genotypes detected by REAG and PCR methods were found to be same in 43 isolates out of 56. As the banding patterns of the isolates were found to be similar in this study, it was thought that an exogenous origin could be the source of infections caused by C. krusei isolates. Both REA of genomic DNA and PCR analysis seem to be useful for the typing of C. krusei, however PCR assay can be preferred as it is a simple and rapid method. As a result, further studies are required for the validation of reproducibility and discriminatory power of these methods.

Case report: Isospora belli infection in a renal transplant recipent.

Isospora belli, an opportunistic protozoon, is one of the most commonly recognized causes of diarrhea in patients with acquired immunodeficiency syndrome (AIDS). Infection is acquired through fecal contaminated food or water, and generally diagnosed by examination of stool and/or duodenum biopsy specimens with acid-fast staining. Here, we present an uncommon case, chronic diarrhea caused by I. belli infection in a patient who is a renal transplant recipient.

Pneumocystis carinii pneumonia in a rheumatoid arthritis patient treated with adalimumab.

Patients with rheumatoid arthritis (RA) have an increased risk of infection as a result of alterations in immune regulation, debility, and comorbid illnesses. TNF-alpha is of central importance in the pathophysiological responses to infection and inflammation, and plays a crucial role in host defence. Pneumocystis carinii is an opportunistic pathogen that commonly affects individuals with inadequate T-cell mediated immune response. Patients with acquired immune deficiency, as well as those receiving immunosuppressive drugs for various conditions have an increased risk of P. carinii pneumonia (PCP). We report the development of PCP in a woman with RA shortly after the initiation of anti-TNF-alpha treatment with adalimumab.

Characteristics of Blastocystis hominis infection in a Turkish university hospital.

In order to determine characteristics of Blastocystis (B.) hominis infection; 770 individuals' stool specimens were examined both by simple and concentration techniques and stained with iodine solution and trichrome in the Parasitology Laboratory of Hacettepe University Faculty of Medicine, Turkey. Among the examined 770 specimens, B. hominis was detected in 94 (12.2%). B. hominis was the most common intestinal parasite among the study group. It was mostly detected with Dientamoeba fragilis. Among the groups the incidence of B. hominis in allergic patients was higher than controls. Among the immunosuppressed patients, B. hominis was detected significantly higher in patients who had solid tumours. Of the 48 individuals who had only B. hominis in their stool the most common symptom was abdominal pain. Concentration technique with trichrome stain was more sensitive than simple smear with lugol solution for the detection of B. hominis. Studies with more patients must be planed to understand the B. hominis infection in solid tumour patients and coexistence of B. hominis and D. fragilis.

Diagnostic value of a dot immunobinding assay for human pulmonary hydatidosis.

The diagnosis of human hydatidosis is primarily made using radiological and serological methods. Radiological methods are generally of low specificity and serological methods lack sensitivity, especially for pulmonary disease. In this study the capabilities of a new rapid test, the hydatid antigen dot immunobinding assay (HADIA), which was developed for the diagnosis of pulmonary hydatidosis, were studied and compared with another immunodiagnostic method, indirect hemagglutination (IHA). The study subjects included 18 patients, 9 women, 9 men; range 7 to 63 years; mean 30 years, with surgically proven pulmonary hydatidosis, a control group comprised of 14 patients; viral respiratory infections (1), cirrhosis (2), connective tissue disease (2), taeniasis (3), and 6 healthy donors. We found that the HA-DIA test had a sensitivity of 67% and specificity of 100%, and that the IHA test had a sensitivity of 50% and specificity of 100%. We conclude that HA-DIA is a simple, rapid, low cost assay that does not require instrumentation and has a higher sensitivity than IHA for the diagnosis of pulmonary hydatidosis.

[The rate of parasite detection over a 5-year period in the parasitology faculty laboratory at the Hacettepe University]. / Hacettepe Universitesi Tip Fakültesi Parazitoloji Laboratuvarinda 5 yillik süre içinde incelenen örneklerde parazit saptanma orani.

The aim of this retrospective study was to investigate the rate of parasite positivity, in the samples which were sent to Parasitology Laboratory of Hacettepe University Medical School, between 1997-2001. A total of 58.150 specimens collected from subjects of whom 42% were adult and 58% were children, have been evaluated for the presence of parasites. Most of the samples (98%) were feces, and the remaining were sputum, cellotapes, blood and cyst materials. One or more parasites were detected in 2.117 (3.6%) of the specimens, and Giardia intestinalis (69.5%), Enterobius vermicularis (9.7%) and Taenia saginata (6.8%) were the most frequently encountered parasites.