Analysis of Parasitic Protozoa at the Single-cell Level using Microfluidic Impedance Cytometry

At present, there are few technologies which enable the detection, identification and viability analysis of protozoan pathogens including Cryptosporidium and/or Giardia at the single (oo)cyst level. We report the use of Microfluidic Impedance Cytometry (MIC) to characterise the AC electrical (impedance) properties of single parasites and demonstrate rapid discrimination based on viability and species. Specifically, MIC was used to identify live and inactive C. parvum oocysts with over 90% certainty, whilst also detecting damaged and/or excysted oocysts. Furthermore, discrimination of Cryptosporidium parvum, Cryptosporidium muris and Giardia lamblia, with over 92% certainty was achieved. Enumeration and identification of (oo)cysts can be achieved in a few minutes, which offers a reduction in identification time and labour demands when compared to existing detection methods.

Cryptosporidium spp. and Giardia spp. in feces and water and the associated exposure factors on dairy farms

The aims of this study were to verify the prevalence of Cryptosporidium spp. and Giardia spp. in animal feces and drinking water on dairy farms and to identify a possible relation between the exposure factors and the presence of these parasites. Fecal samples from cattle and humans and water samples were collected on dairy farms in Paraná, Brazil. Analysis of (oo)cysts in the feces was performed by the modified Ziehl-Neelsen staining and centrifugal flotation in zinc sulfate. Test-positive samples were subjected to nested PCR amplification of the 18SSU ribosomal RNA gene for identification of Cryptosporidium and Giardia and of the gp60 gene for subtyping of Cryptosporidium. Microbiological analysis of water was carried out by the multiple-tube method and by means of a chromogenic substrate, and parasitological analysis was performed on 31 samples by direct immunofluorescence and nested PCR of the genes mentioned above. Identification of the species of Cryptosporidium was performed by sequencing and PCR with analysis of restriction fragment length polymorphisms. The prevalence of Giardia and Cryptosporidium was higher in calves than in adults. Among the samples of cattle feces, Cryptosporidium parvum was identified in 41 (64%), C. ryanae in eight (12.5%), C. bovis in four (6.3%), C. andersoni in five (7.8%), and a mixed infection in 20 samples (31.3%). These parasites were not identified in the samples of human feces. Thermotolerant coliform bacteria were identified in 25 samples of water (45.5%). Giardia duodenalis and C. parvum were identified in three water samples. The gp60 gene analysis of C. parvum isolates revealed the presence of two strains (IIaA20G1R1 and IIaA17G2R2) in the fecal samples and one (IIaA17G2R1) in the water samples. The presence of coliforms was associated with the water source, structure and degradation of springs, rain, and turbidity. The prevalence of protozoa was higher in calves up to six months of age. C. parvum and G. duodenalis were identified in the water of dairy farms, as were thermotolerant coliforms; these findings point to the need for guidance on handling of animals, preservation of water sources, and water treatment.

SUCROSE DENSITY-GRADIENT ISOLATION METHOD INTENDED FOR IMPROVEMENT OF SAMPLE PURITY PRIOR TO AMPLIFICATION OF GIARDIA B-GIARDIN GENE

PCR-based methods have been widely used for detection of Giardia in stool. The sensitivity and hence degree of success of the molecular tool depends on many factors including efficiency of DNA extraction method, in addition to the degree of purity which necessitate removal of a great number of inhibitors from the stool samples. Therefore, Sucrose density gradient isolation method was assessed in this study to be applied prior to nucleic acid extraction and amplification of Giardia duodenalis in stool samples. The methods: Two different approaches were applied in this study to amplify P-giardin gene specific for Giardia duodenalis (syn. G. intestinalis, G. lamblia) using 30 microscopically Giardia positive fecal sam- ples. A) Direct nucleic acid extraction using QIAamp Mini spin columns B) Sucrose density-gradient isolation method prior to DNA extraction using the same extraction Kit. The property of the extracted samples was determined by Spectrophotometric analysis at 260 and at 280 nm. The results showed that in spite of the significant larger amount of nucleic acid obtained by method (A) versus method (B), more pure form of DNA was encountered by method (B) than method (A). Purity encountered by 'method (A) reflected protein contamination of the samples. Following nested PCR reaction, 28 samples of group (B) showed positive bands (511pb), while 8 samples from group (A) failed to be amplified.

Frequency, diagnostic performance of coproantigen detection and genotyping of the Giardia among patients referred to a multi-level teaching hospital in northern India

Giardiasis, a common gastrointestinal parasitic infection in tropics, is diagnosed on stool microscopy (gold standard); however, its sensitivity is low due to intermittent fecal shedding. Coproantigen detection (ELISA) is useful but requires further evaluation. We aimed to study: (a) detection of Giardia by stool microscopy and/or coproantigen, (b) diagnostic performance of fecal antigen detection and microscopy, and c) genotypic characterization of G. lamblia using PCR specific for triose phosphate isomerase (tpi) gene. Stool samples from 2992 patients were examined by microscopy from March 2013 to March 2015 in a multi level teaching hospital in northern India. Giardia coproantigen detection was performed by ELISA in a subset of patients. Genetic characterization of G. lamblia was performed by PCR targeting tpi gene in a subset of microscopy positive stool samples. Of 2992 patients, 132 (4.4%) had Giardia by microscopy (cyst/trophozoite) and/or ELISA. ELISA was performed in 264 patients; of them, 127 were positive by microscopy. Sensitivity, specificity, positive and negative predictive values of ELISA were 91, 91, 94, and 91%, respectively, using microscopy as a gold standard. PCR was performed in 116 randomly selected samples having Giardia using tpi gene. Assemblages A and B were found among 44 (38%) and 72 (62%) patients, respectively. Assemblage B was more often associated with malnutrition and loss of appetite than A (48/72 [67%] vs. 21/44 [48%], P = 0.044 and 17/72 [24%] vs. 14/44 [32%], P = 0.019). We conclude that 4.4% of studied population had giardiasis. Fecal antigen is a useful method for diagnosis and assemblage B is the most common genotype.

IMMUNE-MOLECULAR IDENTIFICATION OF GIARDIA INTESTINALIS IN DIARRHOEAL CHILDREN: COMPARISON OF THREE DIAGNOSTIC METHODS

Giardiasis is a major health problem in both developed and developing world. A variety of methods for diagnosis of Giardia duodenalis cysts or trophozoites is available but still has certain limitations. 100 sample from diarrhoeal children who attending outpatient clinic in Abu El Rish hospital, .Kasr Al Ainy, Faculty of Medicine, Cairo University, Egypt. Giardiasis was diagnosed by direct wet mount, microscopy after formal- ethyl acetate concentration, Ridascreen ELISA assay and n-PCR targeting beta giardin (bg) gene. Using ELISA as reference standard, the methods' sensitivities, specificities, positive (PPV) and negative (NPV) predictive values and positive (LR+) and negative (LR-) likelihood ratios with 95% confidence interval (95% CI) were analyzed.The diagnostic methods were evaluated to determine their impact on the posttest probability using Fagan's nomogram. All the studied methods led to a LR+ higher than 10 indicating ability to ruling in giardiasis. n-PCR recorded LR- equal 0.00 and the probability of giardiasis would be 0% if the test was negative. The methods were also ranked on basis of Multiattribute utility theory and Analytical hierarchy process with ELISA ranked better than n-PCR.

Multiple Simultaneous Gastrointestinal Parasitic Infections in a Patient with Human Immunodeficiency Virus

Patients with the human immunodeficiency virus (HIV) infection are at high risk for gastrointestinal infections causing diarrhea, particularly when those infections are parasitic in nature. This propensity is more pronounced in AIDS, where opportunistic parasitic infections may cause severe diarrhea, marked absorptive dysfunction, and significant risk of mortality. There are scant data regarding parasitic infections among HIV patients in the developed world; most studies and research come from povertystricken areas of South Africa, India, Iran, and the South Pacific. Although multiple infections with the same or different parasites have been reported, simultaneous infections are rare. We present the case of a 35-year-old man who developed a co-infection with Giardia, Cryptosporidium, and Strongyloides, simultaneously, the diagnosis being made after the judicious evaluation of a stool sample. Given the associated morbidity, prompt diagnosis and treatment are needed to avoid further complications in patients with HIV. To our knowledge this is the first reported case of triple parasitic infection in a patient with HIV.

PCR-RFLP method to detect zoonotic and host-specific Giardia duodenalis assemblages in dog fecal samples

Giardia duodenalis is a zoonotic protozoan that parasitizes the upper small intestine of human and many mammals including dogs. To develop a restriction fragment length polymorphism (RFLP) method for typing zoonotic (A, B) and host-specific (C, D) assemblages of G. duodenalis from dog, β-giardin gene was amplified with design primer pairs B3 and B4. The PCR products were digested with restriction enzyme Afa I and Msp I; then, PCR-RFLP method was compared with HRM genotyping and sequencing method for G. duodenalis from dog. The results showed that each of assemblages A-D had unique restriction pattern, which was consistent with the predictive results. Among 21 samples tested by PCR-RFLP, 1 human-derived and 8 dog-derived G. duodenalis were identified as assemblage A; 5 dog-derived G. duodenalis as assemblage C; 7 dog-derived G. duodenalis as assemblage D, which were coincided with the HRM genotyping and sequencing results. It is concluded that the PCR-RFLP is quick, easy, and accurate method for the sequence typing of G. duodenalis zoonotic and specific assemblages from dogs.

OVERDIAGNOSIS OF COELIAC DISEASE IN A PATIENT WITH ASCARIASIS AND GIARDIASIS

There are many errors in the diagnosis of celiac disease. The most common errors are following: underestimation of the importance of comprehensive laboratory and instrumental studies (histological study of biopsy specimens of the duodenal mucosa, molecular- genetic HLA typing and serological markers of celiac disease); the positive clinical dynamics after a strict gluten-free diet is not always confirm the diagnosis of celiac disease; insufficient or incorrect orientation of biopsy specimens of the mucous of the duodenum; illiterate description and interpretation of histopathological data; neglecting to identify possible IgA deficiency, the use of serological tests with low specificity for the diagnosis of celiac disease.

Dog's genotype of Giardia duodenalis in human: first evidence in Europe

The unicellular parasite Giardia duodenalis has been divided to eight assemblages (A-H) from which A and B have the most important zoonotic potential. All remaining genotypes have a strong commitment to various host animals. We present here the first clinical case of a human infection with the dog-specific genotype C of G. duodenalis in Slovakia. The patient, 44-year-old woman, suffered from long-term diarrhoea, abdominal pain, anorexia, weight loss, severe itching and dermatitis in the perianal area. The initial microscopic diagnosis was completed by a nested polymerase chain reaction (PCR) which revealed the first evidence of human giardiasis caused by the dog-specific genotype of G. duodenalis on a European scale. A possible role of dogs in zoonotic transmission of giardiasis and its epidemiological and public health relevance is accentuated.

[Molecular Detection of Giardia lamblia and Cryptosporidium Species in Pet Dogs]

OBJECTIVE

To determine the prevalence of Giardia lamblia and Cryptosporidium species infection in pet dogs, and identify the G. lamblia assemblages and Cryptosporidium species.

METHODS

A total of 315 fresh fecal samples were collected from pet clinics in five counties of Anhui Province and in Hangzhou of Zhejiang Province. Hemi-nested-PCR targeting the GDH gene of G. lamblia and nested-PCR targeting the SSU rRNA gene of Cryptosporidium were performed in all the fecal samples. The PCR products were sequenced and analyzed using bioinformatics methods to identify the G. lamblia assemblages and Cryptosporidium species.

RESULTS

The positive rates of G. lamblia and Cryptosporidium spp. infections in the 315 fecal samples were 3.2% (10/315) and 1.6% (5/315), respectively. Specifically, the two indicators were both significantly higher in dogs ≤12 months (17.8% and 11.1%, respectively) than in adult dogs (0.7% and 0.0%)(P<0.05). However, there was no significant difference in the two indicators between male and female dogs. In addition, two G. lamblia assemblages were identified, assemblages B (n=6) and D (n=4). Sequence analysis of PCR products of the SSU rRNA gene showed that the five Cryptosporidium isolates were C. canis (n =5).

CONCLUSION

The prevalences of G. lamblia and Cryptosporidium infection in pet dogs in Anhui and Zhejiang Provinces were 3.2 % and 1.6 %, respectively. The assemblages of G. lamblia in this study are of types B and D.

Molecular Detection of the Carriage Rate of Four Intestinal Protozoa with Real-Time Polymerase Chain Reaction: Possible Overdiagnosis of Entamoeba histolytica in Nigeria

Diarrhea remains the second largest killer of children worldwide, and Nigeria ranks number two on the list of global deaths attributable to diarrhea. Meanwhile, prevalence studies on potentially diarrheagenic protozoa in asymptomatic carriers using molecular detection methods remain scarce in sub-Saharan countries. To overcome sensitivity issues related to microscopic detection and identification of cysts in stool concentrates, real-time polymerase chain reaction (PCR) was used to analyze genomic DNAs extracted from stool samples from 199 healthy school children for Entamoeba histolytica, E. dispar, Giardia intestinalis, and Cryptosporidium. Questionnaires were administered for epidemiological data collection. E. histolytica was not detected in any of the samples, whereas Giardia (37.2%), E. dispar (18.6%), and Cryptosporidium (1%) were found. Most of the children sourced their drinking water from community wells (91%), while the majority disposed of feces in the bush (81.9%). Our study is the first to use real-time PCR to evaluate the epidemiology of E. histolytica, Giardia, and Cryptosporidium in Nigeria where previous studies using traditional diagnostic techniques have suggested higher and lower carriage rates of E. histolytica and Giardia, respectively. It is also the first study to accurately identify the prevalence of common potentially diarrheagenic protozoa in asymptomatic carriers in sub-Saharan Africa.

Giardiasis surveillance -- United States, 2011-2012

PROBLEM/CONDITION

Giardiasis is a nationally notifiable gastrointestinal illness caused by the protozoan parasite Giardia intestinalis.

REPORTING PERIOD

2011-2012.

DESCRIPTION OF SYSTEM

Forty-four states, the District of Columbia, New York City, the Commonwealth of Puerto Rico, and Guam voluntarily reported cases of giardiasis to CDC through the National Notifiable Diseases Surveillance System (NNDSS).

RESULTS

For 2011, a total of 16,868 giardiasis cases (98.8% confirmed and 1.2% nonconfirmed) were reported; for 2012, a total of 15,223 cases (98.8% confirmed and 1.3% nonconfirmed) were reported. In 2011 and 2012, 1.5% and 1.3% of cases, respectively, were associated with a detected outbreak. The incidence rates of all reported cases were 6.4 per 100,000 population in 2011 and 5.8 per 100,000 population in 2012. This represents a slight decline from the relatively steady rates observed during 2005-2010 (range: 7.1-7.9 cases per 100,000 population). In both 2011 and 2012, cases were most frequently reported in children aged 1-4 years, followed by those aged 5-9 years and adults aged 45-49 years. Incidence of giardiasis was highest in Northwest states. Peak onset of illness occurred annually during early summer through early fall.

INTERPRETATION

For the first time since 2002, giardiasis rates appear to be decreasing. Possible reasons for the decrease in rates during 2011-2012 could include changes in transmission patterns, a recent change in surveillance case definition, increased uptake of strategies to reduce waterborne transmission, or a combination of these factors. Transmission of giardiasis occurs throughout the United States, with more frequent diagnosis or reporting occurring in northern states. Geographical differences might suggest actual regional differences in giardiasis transmission or variation in surveillance capacity across states. Six states did not report giardiasis cases in 2011-2012, representing the largest number of nonreporting states since giardiasis became nationally notifiable in 2002. Giardiasis is reported more frequently in young children, which might reflect increased contact with contaminated water or ill persons, or a lack of immunity.

PUBLIC HEALTH ACTION

Educational efforts to decrease exposure to unsafe drinking and recreational water and prevent person-to-person transmission have the potential to reduce giardiasis transmission. The continual decrease in jurisdictions opting to report giardiasis cases could negatively impact the ability to interpret national surveillance data; thus, further investigation is needed to identify barriers to and facilitators of giardiasis case reporting. Existing state and local public health infrastructure supported through CDC (e.g., Epidemiology and Laboratory Capacity grants and CDC-sponsored Council of State and Territorial Epidemiologists Applied Epidemiology Fellows) could provide resources to enhance understanding of giardiasis epidemiology.

The prevalence of intestinal parasites in children in preschools and orphanages in the Warmia-Masuria province (North-Eastern Poland)

OBJECTIVE

A comparison of the prevalence of intestinal parasites (IP) in preschoolers and orphans in the Warmia-Masuria province (Poland).

MATERIAL AND METHODS

Between 2003-2006 fecal samples and perianal swabs from 1052 preschoolers and 859 orphans were tested on the basis of direct saline and iodine mount, decantation test and the adhesive cellophane tape method.

RESULTS

10.8% of preschoolers and 46,3% of orphans were infected with IP. Among the six detected IP species the E. vermicularis was the most common. Infections of E. vermicularis were diagnosed in 9.5% of preschoolers and 36,7% of orphans. There were statistically significant differences in the distribution of IP between males and females in preschools. IP infections were the most frequent among 7-year-old children, 19.1% in preschools and 65.7% in orphanages, respectively. In preschools, the prevalence of IP was higher among preschoolers from the rural area (17.3%) than from the urban area (10.3%).

CONCLUSION

Orphans and children from rural areas, especially at the age of 7, should be covered by systematic screening with parasitic tests throughout all of Poland. In this group of children, enterobiasis is the main health problem. The promotion of the awareness of IP infections and their prevention among parents and educational staff is required.

Intraepithelial giardia intestinalis: a case report and literature review

The giardiasis is a neglected parasitic disease. The WHO has estimated more than 280 million of human infections each year; however, intraepithelial giardiasis is a rare entity, there are only 5 reports showing invasive giardiasis. A pediatric female patient with chronic abdominal pain, diarrhea, or pasty stools, without fever, was seen in the Gastroenterology and Nutrition Service. The stool studies were negative for pathogens and lactose hydrogen breath test was positive. The presumptive clinical diagnosis was giardiasis and the patient was empirically treated with nitazoxanide. But, the patient persisted with abdominal pain and pasty stools. Endoscopy was indicated to search for Helicobacter and Giardia. Guardian and patient gave written informed consent. Hematological profile was normal. The endoscopy was performed under general anesthesia and the biopsies and duodenal aspirate were obtained. The microscopic analyses of duodenal fluid showed Giardia trophozoites. Electron microscopic analysis was negative for Helicobacter pylori, but Giardia trophozoites with a typical crescent shape within the tissue were found. The patient was treated with tinidazole, subsequent tests showed that lactose absorption was normal, stool examinations were negative for Giardia and abdominal pain had stopped. This case suggest that intraepithelial giardiasis could be a common entity but unseen because the giardiasis diagnosis is usually made on fecal samples. Future studies are necessary to determine the role of intraepithelial trophozoites in giardiasis pathogenic mechanisms.

Clinical and diagnostic features and treatment of giardiasis

Giardia is the most common causes of protozoan diarrhea that lead to significant morbidity and mortality worldwide. Giardiasis can be cause of disturbance of host immune response. The treatment of Giardiasis is unsuccessful in some cases. The purpose of this study was to determine the clinical features and the content of secretory immunoglobulin A (sIgA) among adults and to evaluate efficiency of new plant preparation "Sausalin". The clinical studies were conducted in Karaganda Regional Infection Hospital (Kazakhstan). 250 patients with giardiasis were randomly assigned to receive sausalin at a dose 720 mg/day or ornidazole at 1500 mg/day. Clinical symptoms of giardisis and efficiency of treatment were evaluated. Protozoal clearance rate and clinical symptoms were assessed. Stool samples were collected from 40 patients and examined the content of sIgA. Our study found the prevalence of abdominal pain, dyspeptic syndrome and the symptoms of intoxication in patients with giardiasis. The increase the level of sIgA was detected, especially in females (88 mg/l). Sausalin was more effectiveness than ornidazole. After the treatment, the clearance rate of giardia (85.71% vs. 42.19%; P<0.05) and the clinical efficacy were significantly higher in the sausalin-treated group than in the ornidazole-treated group. The features of clinic manifestations of giardiasis were identified in population of Kazakhstan. Our data suggest the higher level of sIgA was significantly associated with features of clinic manifestations that the participant had. Treatment with sausalin was more effective than treatment with ornidazole. Further research is needed to explain the existence relationship between Giardia infection and host immune response.

An adolescent with chronic giardiasis mimicking anorexia nervosa

A 13-year-old Hispanic female presented with symptoms of abdominal pain, amenorrhea, and unintentional weight loss of 11 kg. Preliminary investigation yielded no immediate causes, and an initial differential included inflammatory bowel disease (IBD), celiac disease, as well as viral, bacterial, or parasitic gastrointestinal infection. Evaluation of these potential diagnoses yielded negative results; thus, the team thought that the patient may be suffering from anorexia nervosa. The patient was discharged to outpatient care, and was treated in our adolescent health clinic, where repeat laboratory testing yielded a positive Giardia-antigen test. The patient was placed on metronidazole, rapidly gained weight, and resumed menstruation soon after. The final diagnosis was chronic giardiasis. Chronic giardiasis is a rare and enigmatic disease that presents with many symptoms similar to chronic gastrointestinal disorders (e.g. IBD and celiac disease) and anorexia nervosa. Practitioners involved in the diagnosis and treatment of anorexia nervosa should be aware of this disorder and include it in differential diagnoses of patients presenting with anorexia nervosa symptoms.

Care-seeking behaviour and diagnostic processes for symptomatic giardiasis in children attending an academic paediatric hospital

Giardiasis is one of the commonest intestinal parasitic infections in Cuba. In order to determine care-seeking behaviour and diagnostic processes in paediatric in-patients with giardiasis, structured questionnaires were administered by interview mothers of children with giardiasis during January to December 2010. During the study period, 97 children were diagnosed with giardiasis, of whom 86 (88·6%) caregivers were interviewed. The median number of days from symptoms onset to the first presentation in a health unit was 2 days (range: 0-15 days). The pattern of care-seeking behaviour was variable; 41 (47·7%) of children initially visited the emergency unit in a paediatric hospital. Sixty-six children had, at least, one further contact for help before diagnosis of giardiasis was made (range: 1-5 contacts) and of the 128 contact visits, 94 (73·4%) were also targeted more to hospitals. There was a median time of 6 days between the first presentation to a health unit until diagnosis, which was mainly made by microscopic examination of duodenal aspiration. Among factors investigated in mothers, only knowing other person with giardiasis had significant association with their ability to suspect giardiasis [odds ratio (OR): 29·8, 95% confidence interval (CI): 3·71-239·4, P = 0·001]. Requesting a faecal specimen or ordering duodenal aspiration for microscopic examination during the first visit appeared associated with correct diagnosis (OR: 3·84, 95% CI: 1·57-9·40, P = 0·003). Efforts should be made to increase doctors' awareness of- and diagnostic skills for childhood giardiasis. At the same time, it is necessary to improve caregivers' awareness about giardiasis.

Imaging and identification of waterborne parasites using a chip-scale microscope

We demonstrate a compact portable imaging system for the detection of waterborne parasites in resource-limited settings. The previously demonstrated sub-pixel sweeping microscopy (SPSM) technique is a lens-less imaging scheme that can achieve high-resolution (<1 µm) bright-field imaging over a large field-of-view (5.7 mm×4.3 mm). A chip-scale microscope system, based on the SPSM technique, can be used for automated and high-throughput imaging of protozoan parasite cysts for the effective diagnosis of waterborne enteric parasite infection. We successfully imaged and identified three major types of enteric parasite cysts, Giardia, Cryptosporidium, and Entamoeba, which can be found in fecal samples from infected patients. We believe that this compact imaging system can serve well as a diagnostic device in challenging environments, such as rural settings or emergency outbreaks.

Extra-intestinal and long term consequences of Giardia duodenalis infections

Giardiasis is the most common waterborne parasitic infection of the human intestine worldwide. The etiological agent, Giardia duodenalis (syn. G. intestinalis, G. lamblia), is a flagellated, binucleated protozoan parasite which infects a wide array of mammalian hosts. Human giardiasis is a true cosmopolitan pathogen, with highest prevalence in developing countries. Giardiasis can present with a broad range of clinical manifestations from asymptomatic, to acute or chronic diarrheal disease associated with abdominal pain and nausea. Most infections are self-limiting, although re-infection and chronic infection can occur. Recent evidence indicating that Giardia may cause chronic post-infectious gastrointestinal complications have made it a topic of intense research. The causes of the post-infectious clinical manifestations due to Giardia, even after complete elimination of the parasite, remain obscure. This review offers a state-of-the-art discussion on the long-term consequences of Giardia infections, from extra-intestinal manifestations, growth and cognitive deficiencies, to post-infectious irritable bowel syndrome. The discussion also sheds light on some of the novel mechanisms recently implicated in the production of these post-infectious manifestations.

Investigation of intestinal parasites in dialysis patients

OBJECTIVE

To search for the opportunistic and other pathogenic intestinal parasites in dialysis patients, and to compare the methods used for diagnosis.

METHODS

This is a randomized study, which recruited participants from the dialysis patients. The study was carried out in the Department of Microbiology, Research Hospital, School of Medicine in Kocaeli University, Kocaeli, Turkey between June 2012 and March 2013. One hundred and forty-two patients were diagnosed with an end-stage renal failure, which underwent dialysis, and 150 healthy volunteers were enrolled in the study. Native-lugol, formol ethyl acetate sedimentation method, trichrome, modified trichrome, acid fast, and Calcofluor staining methods were applied to the stool samples. For the diagnosis of Cryptosporidium spp., Giardia intestinalis (G. intestinalis), and Entamoeba histolytica (E. histolytica), commercially available ELISA kits were used, which detect antigen in the stool.

RESULTS

Parasites were found in 62 of the dialysis patients (43.7%) and 19 of the control group (12.7%). The most encountered parasitic agents in the dialysis patients were Blastocystis spp. (23.9%), G. intestinalis (8.5%), E. histolytica (2.1%), Microsporidia spp. (2.1%), and Cryptosporidium spp. (2.1%). The parasite detection rate of the formol ethyl acetate sedimentation method was found to be higher than native-lugol (p<0.05).

CONCLUSION

To protect the dialysis patients with diarrhea from parasitic infections, it is important to carry out interval stool examinations with trichrome, modified trichrome, acid fast, and Calcofluor staining methods, and the ELISA method, which detects antigen in the stool.

Prevalence of giardiasis in children attending semi-urban daycare centres in Guatemala and comparison of 3 giardia detection tests

Giardia intestinalis is an intestinal parasite widely prevalent in children attending daycare centres worldwide and has been associated with undernutrition. Stool samples from 48 Guatemalan children (aged 1.5-7 years) attending participating daycare centres were analyzed over five weeks for presence of Giardia intestinalis using light microscopy, ELISA, and rapid dipstick test. Giardia prevalence rates were 43.7% at Week 0 and 44.7% at Week 4, based on ELISA. Intensity, but not prevalence, of infection showed a trend toward decreased weight-for-age (1-tailed p = 0.08). We believe that ELISA analysis of stool samples may be further adapted for measuring the intensity of infection in humans.

Detection of Giardia lamblia, Cryptosporidium spp. and Entamoeba histolytica in clinical stool samples by using multiplex real-time PCR after automated DNA isolation

Diagnosis of intestinal parasites in stool samples is generally still carried out by microscopy; however, this technique is known to suffer from a low sensitivity and is unable to discriminate between certain protozoa. In order to overcome these limitations, a real-time multiplex PCR was evaluated as an alternative approach for diagnosing Giardia lamblia, Cryptosporidium spp. and Entamoeba histolytica in stool samples.Therefore, a total of 631 faecal samples were analysed both by microscopy as well as by real-time PCR following automated DNA extraction. Results showed that real-time PCR exhibited sensitivity and specificity of both 100%, whereas traditional microscopy exhibited sensitivity and specificity of 37.5% and 99.8% respectively. As real-time PCR provides simple, sensitive and specific detection of these three important pathogenic protozoan parasites, this technique, rather than microscopy, has become our diagnostic method of choice for the detection of enteric protozoan parasites for the majority of patients.

[Common variable immunodeficiency: digestive involvement of a systemic disease]

Common variable immunodeficiency is characterized by a primary deficiency in antibody production that is clinically manifested by respiratory recurrent infections and gastrointestinal diseases (infectious, inflammatory and neoplastic). Above 50% of the patients have diarrhea and 10% develop idiopathic malabsorption and weight loss. We present the case of a 34-year-old woman submitted to our service for chronic diarrhea, abdominal pain and bloating and history of recurrent respiratory infections since childhood. The laboratory assessment showed severe hypoproteinemia and confirmed low IgG, IgA and IgM levels. Upper gastrointestinal endoscopy and videocapsule endoscopy showed a nodular duodenum with multiple polypoid-like formations all through the small bowel. Histology confirmed chronic duodenitis and Giardia lamblia infection. With the diagnosis of common variable immunodeficiency, monthly intravenous gammaglobulin infusion was initiated and metronidazole was indicated for Giardia lamblia infection achieving excellent clinical and laboratory response.

Evaluation of paediatric patients with protein losing enteropathy a single centre experience

OBJECTIVE

The aim of the study is to evaluate paediatric patients with protein losing enteropathy (PLE).

METHODS

Fourteen cases diagnosed as PLE were evaluated in terms ofaetiologies, diagnostic methods, laboratory findings, treatment procedures and long-term prognosis.

RESULTS

Four of the cases had coeliac disease, three intestinal lymphangiectasia, three giardia infection, one H pylori infection and three cytomegalovirus (CMV) infection. Histopathological examinations of duodenum specimens revealed total villous atrophy in four cases, lymphatic dilatation in three cases, severe nodular appearance in four cases and no pathology in four cases. All of the cases except patients with intestinal lymphangiectasia were controlled by the appropriate treatment given for the underlying disease. The cases with CMV infection were treated with only supportive treatment and gancyclovir therapy was not needed.

CONCLUSION

When proteinuria is not detected in well-appearing children admitted with oedema, PLE must be considered.