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ORIGINAL ARTICLE |
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Year : 2015 | Volume
: 28
| Issue : 3 | Page : 635-641 |
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Coccidian parasitic infections in liver transplant recipients
Abdel-Gawad E Saad, Wafaa M Elkersh, Amira F Afifi, Y Hawash, Sawsan S Shendi MBBCh
Department of Medical Parasitology, National Liver Institute, Faculty of medicine, Menoufia University, Menoufia, Egypt
Date of Submission | 17-Nov-2014 |
Date of Acceptance | 01-Dec-2014 |
Date of Web Publication | 22-Oct-2015 |
Correspondence Address: Sawsan S Shendi Shebin El Kom, Menoufia Egypt
Source of Support: None, Conflict of Interest: None | Check |
DOI: 10.4103/1110-2098.167780
Background Coccidian parasites are reported in patients with low immunity. However, there is little knowledge of coccidian parasites in patients who have undergone liver transplantation. Objective The aim of this study was to assess coccidian parasitic infections in liver transplant recipients using microscopic and immunologic assays. Patients and methods Seventy-five participants were divided into two groups: group I included 50 participants from March 2011 to June 2013 during the first 6 months after liver transplantation and group II included 25 apparently healthy participants. Fecal specimens were subjected to microscopic examination for enteric protozoa stained with iodine, trichrome, and modified Ziehl-Neelsen stains. Furthermore, all fecal specimens were subjected to examination for Cryptosporidium oocyst surface antigen using the enzyme-linked immunosorbent assay (ELISA) test. Serum samples of all participants were tested for Toxoplasma IgM and IgG antibodies using a commercially available kit Toxoplasma IgM and IgG ELISAs. Results Of all participants, eight (16%) liver transplant recipients were positive for enteric coccidia. Cryptosporidium oocysts were identified in 12% of patients, whereas Cryptosporidium parvum oocyst surface antigen was detected in 20% of patients. Cyclospora oocysts were observed in 6%. Importantly, the positivity rate was high (62.5%) in those patients who had diarrhea. The Toxoplasma IgG antibodies were identified in 28% of patients, whereas the IgM antibodies were detected in 18% of patients. Out of nine Toxoplasma IgM-positive patients, five (55.6%) presented with lymphadenopathy and out of 14 patients seropositive for Toxoplasma IgG, 12 (85.7%) presented with lymphadenopathy. Conclusion Enteric coccidian parasites such as Cryptosporidium should always be taken into account among liver transplant recipients when investigating the etiologies of diarrhea, which occurs in patients in whom the immune system has been suppressed. Toxoplasma gondii is a common opportunistic parasite and causes enlarged lymph nodes among liver transplant recipients. Detection of anti-Toxoplasma IgM and IgG by the ELISA technique is an important screening test that is used commonly as it is rapid and easy to use. Keywords: Coccidia, enzyme-linked immunosorbent assay, liver transplantation, modified Ziehl-Neelsen stain, trichrome stain
How to cite this article: Saad AGE, Elkersh WM, Afifi AF, Hawash Y, Shendi SS. Coccidian parasitic infections in liver transplant recipients. Menoufia Med J 2015;28:635-41 |
How to cite this URL: Saad AGE, Elkersh WM, Afifi AF, Hawash Y, Shendi SS. Coccidian parasitic infections in liver transplant recipients. Menoufia Med J [serial online] 2015 [cited 2024 Mar 29];28:635-41. Available from: http://www.mmj.eg.net/text.asp?2015/28/3/635/167780 |
Introduction | | |
Coccidian protozoa are unicellular microscopic parasites that can infect a broad range of mammalian hosts including humans. These parasites are classified into intestinal (enteric) and tissue protozoa. Enteric coccidian parasites including Cryptosporidium, Cyclospora, and Isospora genera usually inhabit the intestinal tract of humans, causing diarrhea. Infections usually occur through accidental ingestion of the fully sporulated oocysts contaminating either water or raw food. Direct or indirect person-to-person transmission of infection is also recognized as a source of infection [1]. In patients with an intact immune system, infections are usually localized to the intestinal tract, causing mild, self-limiting diarrhea that resolves spontaneously within days to a few weeks. However, in patients with weakened immunity, diarrhea may be severe and the infection can extend beyond the intestine, and may be life threatening [2].
In contrast, tissue coccidian parasites such as Toxoplasma gondii inhabit various host tissues, causing a broad range of site-dependent clinical pictures. Toxoplasmosis is a worldwide parasitic infection caused by T. gondii in most mammalian hosts including humans [3]. Toxoplasmosis is primarily acquired orally, through the blood stream, and through congenital infections [4]. In adults, infection does not cause serious illness; however, blindness and mental retardation may be fatal in congenitally acquired infections. Like the enteric coccidian, infection with T. gondii may be severe in patients with compromised immunity [4].
Clinical pictures of both enteric as well as tissue coccidian are different and the diagnosis should be made primarily on the basis of laboratory tests. Wet-mounted preparations stained with iodine, trichrome, modified Ziehl-Neelsen (mZN), or florescent dyes are commonly used for the diagnosis. However, these microscopically based detection methods are varied in their sensitivities [5]. Recently, several numbers of commercially immunoassays became available with relatively higher diagnostic performances [6]. In contrast, the diagnosis of T. gondii infection is still made primarily on the basis of some serological assays, especially for epidemiological studies [7].
Both types of coccidian parasites have been studied widely in immune cell-deficient patients such as patients with uncontrolled HIV infection [8]. In contrast, few previous studies have investigated coccidian parasites in patients who have undergone solid organs transplantation [9],[10],[11],[12],[13]. Almost all these studies have been carried out in a small number of cases and could be biased by the absence of control groups. In Egypt, liver transplantation surgeries are widely carried out in highly specialized hospitals on a relatively wider scale than earlier. Furthermore, the postoperative liver transplantation survival rate has increased relatively [14] and enables the inclusion of larger numbers of cases to be screened for these coccidian parasites. All the aforementioned facts led the authors to carry out this case-control study to assess coccidian parasitic infections in liver transplant recipients using microscopic and immunologic assays.
Patients and methods | | |
This study included 75 individuals who were divided into two groups. Group I included 50 immunosuppressed liver transplant recipients (38 men and 12 women) of different ages (15-55 years) who were selected from among those who had undergone the operation at the National Liver Institute from March 2011 to June 2013 during the first 6 months after the operation. Group II included 25 apparently healthy individuals, matched in terms of age and sex to an extent, as a control group. In both groups, 20 and seven individuals resided in rural areas, respectively, and 30 and 18 participants resided in urban areas, respectively; 37 and 19 participants used tap water and 13 and six participants used filtered water, respectively.
A questionnaire that included clinical data and time of operation was completed by each participant. Three stool samples for 3 successive days of each individual were collected in clean, labeled sterile containers. Microscopic examination was then performed using the iodine-stained wet mount stool method to determine the presence of enteric helminthes and/or enteric protozoa such as Entamoeba histolytica and Giardia lamblia [15]. Trichrome stain was used for the diagnosis of enteric protozoa such as Blastocystis hominis [16] and mZN stain was used for the diagnosis of Cryptosporidium spp., as well as other acid-fast enteric coccidia such as Cyclospora and Isospora species [17]. Fresh stool samples were also subjected to enzyme-linked immunosorbent assay (ELISA) testing for immunological detection of Cryptosporidium oocyst antigen in stool using the Ridascreen Cryptosporidium test from Biopharm (Berlin, Germany) [18]. Blood samples were collected and sera were stored at −20C for serological analysis of anti-T. gondii IgG and IgM antibodies using Toxoplasma IgG and an IgM ELISA from Sigma (Leon, France) [19].
Ethical consideration
All patients included in the study were informed of the study objectives and a written signed consent was obtained. Ethical approval was obtained from the Committee of Research, Publications and Ethics of Faculty of Medicine, Menoufia University.
Statistical methods
All data were subjected to statistical analysis using SPSS software (version 17; SPSS Inc., Chicago, Illinois, USA). The χ2 -test was used to determine the relationship between the presence of coccidian in patients who provided the stool samples and other parameters, such as different symptoms and the correlated characteristics. The Fischer exact test and the Mann-Whitney test were used.
P-value of more than 0.05 was considered to indicate a statistically insignificant difference and P-value of less than 0.05 was considered to indicate a statistically significant difference.
Results | | |
[Table 1] shows parasitic infections by iodine-stained wet mount; two (4%) cases with Entamoeba complex (E. histolytica/E. dispar) cysts were detected in group I and two (8%) positive cases in group II. Also, six (12%) positive cases with G. lamblia cysts were detected in group I. The difference between the two groups was statistically nonsignificant (P > 0.05). | Table 1: Number and percentage of non-coccidian parasitic infections by iodine-stained concentrated stool examination among the groups studied
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[Table 2] and [Figure 1] and [Figure 2] show parasitic infections by trichrome stain; one (2%) patient with an Entamoeba complex cyst, five (10%) patients with G. lamblia cysts, and six (12%) patients with B. hominis were detected. Mixed infection of an Entamoeba complex cyst and B. hominis was present in one (2%) patient; also, mixed infection of a Giardia cyst and B. hominis was detected in one (2%) patient in group I; whereas two (8%) cases with Entamoeba complex cysts were detected in group II. The difference between the two groups was statistically nonsignificant (P > 0.05). | Figure 2: Trichrome stain of stool shows a Giardia lamblia cyst ( ×1000).
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| Table 2: Number and percentage of parasitic infections by trichrome stain stool examination among the groups studied
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[Table 3] and [Figure 3] and [Figure 4] show parasitic infections by mZN stain, which detected Cryptosporidium oocysts in four (8%) patients and Cyclospora oocysts in two (4%) patients in group I. Mixed infection of a Cryptosporidium oocyst and a Giardia cyst was found in one (2%) patient; also, mixed infection of Cryptosporidium and Cyclospora oocysts was found in one (2%) patient in group I. No coccidian parasitic infections were detected in group II. | Figure 3: Modified Ziehl– Neelsen stain of stool shows red oocysts of Cryptosporidium against the blue background ( ×1000).
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| Figure 4: Modified Ziehl– Neelsen stain of stool shows oocysts of Cyclospora (×1000).
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| Table 3: Number and percentage of parasitic infections by modified Ziehl– Neelsen stain stool examination among the groups studied
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[Table 4] shows the distribution of symptoms and signs in infected cases with coccidian infection detected by stool examination using the mZN stain in group I; the most frequent symptoms recorded in group I were diarrhea and flatulence (62.5%), followed by abdominal pain (37.5%), nausea (37.5%), lymphadenopathy (25%), and vomiting (12.5%). | Table 4: Distribution of symptoms and signs in infected cases with coccidian infection detected by stool examination using the modified Ziehl– Neelsen stain in group I
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[Table 5] shows Ridascreen Cryptosporidium oocysts antigen in stool among the groups studied; 10 (20%) positive cases were detected in group I and no positive reactions were detected in group II, and the difference between the two groups was statistically significant (P < 0.05). | Table 5: Number and percentage of positive samples detected by Ridascreen Cryptosporidium oocysts antigen in stool detected among the groups studied
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[Table 6] shows a comparison between the results of the mZN stain and Ridascreen Cryptosporidium oocysts antigen in stool in group I; out of 10 patients positive for Ridascreen Cryptosporidium oocysts antigen in stool, four (40%) patients were negative for coccidian parasitic infections by mZN, four (40%) patients showed a Cryptosporidium oocyst, one (10%) patient had a mixed Cryptosporidium and Giardia oocyst, and one (10%) patient had mixed Cryptosporidium and Cyclospora oocyst by the mZN stain in group I. Out of 40 patients negative by the Ridascreen test, two (5%) patients showed a Cyclospora oocyst by the mZN stain in group I. This variation was statistically significant (P < 0.05).
[Table 7] shows anti-Toxoplasma antibodies detected by ELISA - IgM and IgG - among the groups studied; nine (18%) patients in group I were seropositive for Toxoplasma IgM. This difference was statistically significant (P < 0.05). However, 14 (28%) patients in group I were seropositive for Toxoplasma IgG, and this difference was statistically significant (P < 0.05). | Table 6: Comparison between the results of the modified Ziehl– Neelsen stain and Ridascreen Cryptosporidium oocysts antigen in stool in group I
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| Table 7: Number and percentage of anti-Toxoplasma antibodies detected by enzyme-linked immunosorbent assay – IgM and IgG – among the groups studied
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[Table 8] shows lymphadenopathy in group I according to ELISA serodiagnosis of IgM and IgG; out of nine Toxoplasma IgM-positive patients, five (55.6%) patients presented with lymphadenopathy. Also, out of 41 seronegative patients for Toxoplasma IgM, 12 (29.3%) patients presented with lymphadenopathy. These differences were statistically nonsignificant (P > 0.05). Out of 14 seropositive patients for Toxoplasma IgG, 12 (85.7%) patients presented with lymphadenopathy, whereas out of 36 seronegative patients for Toxoplasma IgG, five (13.9%) patients presented with lymphadenopathy. These differences were statistically significant (P < 0.05). | Table 8: Percentage of lymphadenopathy in group I according to enzyme-linked immunosorbent assay serodiagnosis of IgM and IgG
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Discussion | | |
The numbers of immunosuppressed individuals continue to increase in developing countries as a result of medical interventions with more aggressive immunosuppressive therapies for immune-mediated disorders, hematopoietic diseases, and solid organ transplantation (SOT), with approximately one million transplants performed annually [20]. One of the most common complaints after liver transplantation is diarrhea. Liver transplantation requires prescription of immunosuppressive medications immediately after the operation. Postoperative diarrhea may be attributed to infections or to the side effects of medication. Enteric coccidian parasites are increasingly being recognized as causes of gastroenteritis in these immunocompromised patients [10]. Similarly, toxoplasmosis after SOT is frequently associated with high morbidity and mortality. It may result from primary infection or reactivation of a latent infection [21].
In the present study, iodine-stained stool examination showed that 4% of patients in group I and 8% of patients in group II had Entamoeba complex cysts, whereas 12% of patients G. lamblia cysts in group I. These results were in agreement with those reported by Baiomy et al. [22] in Egypt; they found that G. lamblia was a common parasite (10%) among immunocompromised patients. However, higher results were reported by Arslan et al. [12], who found that 27.2% of patients had a G. lamblia cyst in diarrhea episodes related to an infectious agent among SOT patients and 21.2% of patients in diarrhea episodes among the participants in the control group; also, 3% of SOT patients and 21.2% of the participants in the control group had an E. histolytica cyst in diarrhea episodes. They reported that E. histolytica was more commonly found in the control group than in the SOT group. This study was carried out on 40 renal and three liver SOT patients in Turkey at Baskent University Hospital.
In the present study, it was found that stool examination using trichrome stain detected 2% of patients with Entamoeba complex cysts, 10% with G. lamblia cysts, and 12% with B. hominis. Similar results were reported by Zali et al. [23], who found G. lamblia (7.3%), B. hominis (4.4%), and Entamoeba coli (3.9%) infections in HIV-positive individuals stool assessed by trichrome stain. However, Arslan et al. [12] detected G. lamblia in 20.9% of patients, E. histolytica in 2.3% of patients, and B. hominis in 2.3% of patients by trichrome stain obtained from SOT recipients.
On stool examination by mZN stain, Cryptosporidium oocysts were detected in 8% of patients, Cyclospora oocysts in 4% of patients, and mixed Cryptosporidium oocyst infections in 4% of patients with other parasites in group I. However, Hammouda et al. [24] reported that coccidian oocysts (Cryptosporidium 13.3% and Isospora belli 2.2%) were observed clearly using Ziehl-Neelsen and chromotrope-based stains in immunosuppressed patients with chronic diarrhea receiving chemotherapeutic agents. In contrast, in Turkey, Aksoy and Tuncay [25] found I. belli oocysts in 0.4% of patients (0.2% of patients were HIV positive and 0.2% had undergone liver transplantation) in stool examined by acid-fast stain. In terms of acute/chronic hepatitis B liver failure, Cryptosporidium infection was recorded in 6% of patients, which was higher than that found in chronic hepatitis B infection patients (0.8%) detected by modified acid-fast staining and auramine-phenol staining [26]. Also, Baiomy et al. [22] found a 7% infection rate in malignant patients by Cryptosporidium parvum, a 3% infection rate with Cyclospora cayetanensis, and a 2% infection rate with microsporidia species; mixed infection was detected in 2% of patients with C. parvum and Cyclospora.
In terms of the distribution of symptoms and signs in infected cases, the most frequent symptoms were flatulence and diarrhea (62.5%), followed by abdominal pain (37.5%), nausea (37.5%), lymphadenopathy (25.0%), and vomiting (12.5%). In the same context, Arslan et al. [12] found that abdominal pain was the most frequent symptom (76.9%), followed by nausea (44.2%) and vomiting (19.6%) among diarrhea episodes in SOT recipients.
Ridascreen Cryptosporidium oocysts antigen in stool was detected in 20% of patients in group I. The difference between the two groups was significant (P < 0.05). These results were in agreement with those of Krause et al. [13], who detected Cryptosporidium antigen in stool in 11% of patients (four kidney recipient, one liver, and one heart transplant recipient) during all episodes of gastroenteritis among SOT recipients hospitalized in Schneider Children's Medical. However, higher results were reported in India by Uppal et al. [27]); they found Cryptosporidium in 67.3 and 77.5% of AIDS patients with diarrhea in the ART clinic of Lok Nayak Hospital, New Delhi, by antigen ELISA and nested PCR assay, respectively. In addition, Omoruyi et al. [28] proved that the ELISA technique was more suitable for determination of the presence of Cryptosporidium oocysts antigen. They found that the incidence of Cryptosporidium was 74.3% among HIV-positive diarrheagenic patients and 76.8% among HIV-negative diarrheagenic patients at Victoria Hospital, Alice, Eastern Cape Province of South Africa.
In the present study, comparison between the results of the mZN stain and Ridascreen Cryptosporidium oocysts antigen in stool in group I was statistically significant (P < 0.05), which proved that the Ridascreen Cryptosporidium oocysts antigen test was more valuable and diagnostic than the mZN stain. These results were in agreement with those reported by Khurana et al. [29]; they detected Cryptosporidium in 3.9 and 4.8% of HIV-seropositive by mZN staining and antigen detection ELISA, respectively. Also, Omoruyi et al. [28] found Cryptosporidium in 37.1 and 74.3% among HIV-positive diarrheagenic patients by mZN staining and ELISA, respectively.
In the current study, 18% of patients in group I were seropositive for Toxoplasma IgM using ELISA, and this difference was statistically significant (P < 0.05), whereas 28% of patients in group I were seropositive for Toxoplasma IgG. This difference was statistically significant (P < 0.05). A higher rate was reported by Caner et al. [9] in western Turkey; they reported that 67.5% of the 40 transplant recipients were seropositive for Toxoplasma infection and therefore at risk of reactivated infection. In another study, anti-Toxoplasma-specific IgG and IgM antibodies were found in 54 and 4%, respectively, of serum samples obtained from renal transplant recipients [30]. Moreover, Martina et al. [21] reported two cases of seropositive T. gondii in renal transplant recipients.
In the current work, of nine Toxoplasma IgM-positive patients, 55.6% presented with lymphadenopathy. Similarly, out of 41 patients seronegative for Toxoplasma IgM, 29.3% presented with lymphadenopathy because of other causes. However, out of 14 patients seropositive for Toxoplasma IgG, 85.7% presented with lymphadenopathy and out of 36 patients seronegative for Toxoplasma IgG, 13.9% presented with lymphadenopathy. These results were in agreement with those reported in Turkey by YariktaΊ et al . [31]; they reported other causes of positive IgG: 48% of patients had hypertrophic tonsillitis (11.3%), hypertrophic tonsillitis, and adenoid hyperplasia (18.8%), adenoid hyperplasia (5.6%), and lymphadenopathy of the neck (7.5%), and positive IgM was found in 9.4% of patients with hypertrophic tonsillitis (1.8%), hypertrophic tonsillitis, and adenoid hyperplasia (1.8%), and lymphadenopathy of the neck (5.6%).
Conclusion | | |
Enteric coccidian parasites such as Cryptosporidium should always be taken into account among liver transplant recipients when investigating the etiologies of diarrhea, which occurs in patients in whom the immune system has been suppressed. T. gondii was a common opportunistic parasite and caused enlarged lymph nodes among liver transplant recipients. Detection of anti-Toxoplasma IgM and IgG by the ELISA technique is an important screening test commonly used as it is rapid and easy to use.
Acknowledgements | | |
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8]
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