Parasitic Infection in Renal Transplant Recipients

Reactivation of latent infections in solid organ transplant recipients from sub-Saharan Africa: What should be remembered?

International migration from Sub-Saharan African countries to the European Union and the United States has significantly increased over the past decades. Although the vast majority of these immigrants are young and healthy people, a minority can be affected by chronic conditions eventually leading to solid organ transplantation (SOT). Importantly, these candidates can bear geographically restricted fungal and parasitic latent infections that can reactivate after the procedure. An appropriate evaluation before transplantation followed by treatment, whenever necessary, is essential to minimize such risk, as covered in the present review. In short, infection due to helminths (Schistosoma spp. and Strongyloides stercoralis) and intestinal protozoa (Entamoeba histolytica, Giardia lamblia or Cyclospora cayetanensis) can be diagnosed by multiple direct stool examination, serological assays and stool antigen testing. Leishmaniasis can be assessed by means of serology, followed by nucleic acid amplification testing (NAAT) if the former test is positive. Submicroscopic malaria should be ruled out by NAAT. Screening for Histoplasma spp. or Cryptococcus spp. is not routinely indicated. Consultation with an Infectious Diseases specialist is recommended in order to adjust preemptive treatment among Sub-Saharan African SOT candidates and recipients.

Giardia lamblia mimicking acute graft versus host disease after allogeneic hematopoietic stem cell transplantation: A case report

RATIONALE

As the major complications post allogeneic hematopoietic stem cell transplantation (allo-HSCT), gastrointestinal disorders were most commonly ascribed to acute graft-versus-host disease (aGVHD) and opportunistic infections. Though Giardia lamblia (G lamblia) is the most common waterborne parasite of intestinal infection worldwide, seldom has it been reported in a patient with acute severe aplastic anemia after allo-HSCT.

PATIENT CONCERNS

A 23-year-old male with severe aplastic anemia developed diarrhea, abdominal cramps, bloating, nausea, vomiting, fever, weight loss, and fatigue after allo-HSCT.

DIAGNOSIS

Stool examinations for ova and parasites showed Giardia trophozoites and cysts.

INTERVENTIONS

Methylprednisolone was stopped and the patient was intravenously treated with a 7-day course of metronidazole (500 mg, tid.). Simultaneously, cyclosporine (5 mg/kg) was continually utilized for suspicious gut GVHD.

OUTCOMES

The Giardia lamblia in stool turned negative and his symptoms were resolved after the 7-day course.

LESSONS

Incorporating non-invasive monitoring of stool examination for ova and parasites in the follow-up algorithm for post-HSCT patients can expedite clinical decision-making in the differential diagnoses for aGVHD even in the non-endemic area. Metronidazole therapy can be well-tolerated in HSCT patients with giardiasis.

Severe Strongyloides stercoralis infection in kidney transplant recipients: A multicenter case-control study

BACKGROUND

Severe Strongyloides stercoralis infection in kidney transplant recipients is associated with considerable morbidity and mortality, although little is known about the risk factors for such infection.

METHODOLOGY/PRINCIPAL FINDINGS

This was a retrospective, multicenter, case-control study in which we assessed the risk factors for and clinical outcomes of severe S. stercoralis infections in kidney transplant recipients in Brazil. We included 138 kidney transplant recipients: 46 cases and 92 controls. Among the cases, the median number of days from transplantation to diagnosis was 117 (interquartile range [IQR], 73.5-965) and the most common clinical findings were gastrointestinal symptoms (in 78.3%) and respiratory symptoms (in 39.1%), whereas fever and eosinophilia were seen in only 32.6% and 43.5%, respectively. The 30-day all-cause mortality among the cases was 28.3% overall and was significantly higher among the cases of infection occurring within the first three months after transplantation (47% vs. 17.2%, P = 0.04). The independent risk factors were receiving a transplant from a deceased donor (odds ratio [OR] = 6.16, 95% confidence interval [CI] = 2.05-18.5), a history of bacterial infection (OR = 3.04, 95% CI = 1.2-7.5), and a cumulative corticosteroid dose (OR = 1.005, 95% CI = 1.001-1.009). The independent predictors of mortality were respiratory failure (OR = 98.33, 95% CI = 4.46-2169.77) and concomitant bacteremia (OR = 413.00, 95% CI = 4.83-35316.61).

CONCLUSIONS/SIGNIFICANCE

Severe S. stercoralis infections are associated with considerable morbidity and mortality after kidney transplantation. In endemic areas, such infection may occur late after transplantation, although it seems to be more severe when it occurs earlier after transplantation. Specific risk factors and clinical manifestations can identify patients at risk, who should receive prophylaxis or early treatment.

Enteroparasitosis infections among renal transplant recipients in Khartoum state, Sudan 2012-2013

Objectives

Renal transplantation procedure markedly increased over the past few decades. The risk of harboring parasitic diseases may affect transplant recipients during life expectancy. We aimed in this study to determine the enteroparasitosis frequency among renal transplant recipients in Khartoum state, Sudan. A case–control hospital-based study performed between November 2012 and May 2013, on 300 renal transplant recipients attending Sudanese Kidney Association hospital in Khartoum state, Sudan, along with 300 normal healthy individuals matching the case in age and sex. Stool samples were collected for parasitological studies.

Results

Out of the 300 renal transplant recipients: 242 (80.7%) were males mean age 43 ± 11.28 and 58 (19.3%) were females mean age 41 ± 13.41. Intestinal parasitic infection was observed in 118 participants and the overall frequency was 19.7%; of which 64 were cases (21.3%) and 54 (18.0%) were controls. Eight different species of intestinal parasites were identified; Entamoeba histolytica/dispar (7.5%), Entamoeba coli (6.5%), Giardia lambelia (3.2%), Cryptosporidium parvum (1.2%), Ascaris lumbricoides (0.6%), Enterobius vermicularis (0.3%), (0.2%) for each of Strongyloides stercoralis and Hymenolepis nana.

Solid Organ Transplant and Parasitic Diseases: A Review of the Clinical Cases in the Last Two Decades

The aim of this study was to evaluate the occurrence of parasitic infections in solid organ transplant (SOT) recipients. We conducted a systematic review of literature records on post-transplant parasitic infections, published from 1996 to 2016 and available on PubMed database, focusing only on parasitic infections acquired after SOT. The methods and findings of the present review have been presented based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) checklist. From data published in the literature, the real burden of parasitic infections among SOT recipients cannot really be estimated. Nevertheless, publications on the matter are on the increase, probably due to more than one reason: (i) the increasing number of patients transplanted and then treated with immunosuppressive agents; (ii) the “population shift” resulting from immigration and travels to endemic areas, and (iii) the increased attention directed to diagnosis/notification/publication of cases. Considering parasitic infections as emerging and potentially serious in their evolution, additional strategies for the prevention, careful screening and follow-up, with a high level of awareness, identification, and pre-emptive therapy are needed in transplant recipients.

Molecular appraisal of intestinal parasitic infection in transplant recipients

BACKGROUND & OBJECTIVES

Diarrhoea is the main clinical manifestation caused by intestinal parasitic infections in patients, with special reference to transplant recipients who require careful consideration to reduce morbidity and mortality. Further, molecular characterization of some important parasites is necessary to delineate the different modes of transmission to consider appropriate management strategies. We undertook this study to investigate the intestinal parasitic infections in transplant recipients with or without diarrhoea, and the genotypes of the isolated parasites were also determined.

METHODS

Stool samples from 38 transplant recipients comprising 29 post-renal, two liver and seven bone marrow transplant (BMT) recipients presenting with diarrhoea and 50 transplant recipients (42 post-renal transplant, eight BMT) without diarrhoea were examined for the presence of intestinal parasites by light microscopy using wet mount, modified Ziehl-Neelsen staining for intestinal coccidia and modified trichrome staining for microsporidia. Genotypes of Cryptosporidium species were determined by multilocus genotyping using small subunit ribosomal (SSUrRNA), Cryptosporidium oocyst wall protein (COWP) and dihydrofolate reductase (DHFR) as the target genes. Assemblage study for Giardia lamblia was performed using triose phosphate isomerase (TPI) as the target gene. Samples were also screened for bacterial, fungal and viral pathogens.

RESULTS

The parasites that were detected included Cryptosporidium species (21%, 8/38), Cystoisospora (Isospora) belli (8%, 3), Cyclospora cayetanensis (5%, 2), G. lamblia (11%, 4), Hymenolepis nana (11%, 4), Strongyloides stercoralis (3%, 1) and Blastocystis hominis (3%, 1). Multilocus genotyping of Cryptosporidium species at SSUrRNA, COWP and DHFR loci could detect four isolates of C. hominis; two of C. parvum, one of mixed genotype and one could not be genotyped. All the C. hominis isolates were detected in adult post-renal transplant (PRT) recipients, whereas the C. parvum isolates included a child with BMT and an adult with PRT. Clostridium difficle, cytomegalovirus and Candida albicans were found in 2, 3 and 2 patients, respectively.

INTERPRETATION & CONCLUSIONS

In the present study, C. hominis was observed as an important parasite causing intestinal infections in transplant recipients. Multilocus genotyping of Cryptosporidium species could detect four isolates of C. hominis; two of C. parvum, one of mixed genotype and one could not be genotyped. Genotyping of G. lamblia revealed that assemblage B was most common.

Association between Strongyloides stercoralis infection and cortisol secretion in alcoholic patients

A higher prevalence of Strongyloides stercoralis infections has been reported in alcoholic patients compared to nonalcoholic patients living in the same area. Excessive alcohol consumption increases the levels of endogenous corticosteroids that subsequently enhance the fecundity of S. stercoralis parthenogenetic females. These corticosteroids also enhance the transformation of rhabditiform larvae into infective filariform larvae by mimicking the effect of the ecdysteroid hormones produced by the parasite, thus leading to autoinfection. In addition, alterations in the intestinal barrier and host immune response contribute to the development of hyperinfection and severe strongyloidiasis in alcoholic patients. The aim of this study was to evaluate the frequency of S. stercoralis infections in alcoholic patients and to determine the association between S. stercoralis infection and endogenous cortisol levels. The frequency of infection was evaluated in 332 alcoholic and 92 nonalcoholic patients. The parasitological diagnosis was carried out by agar plate culture, the modified Baermann-Moraes method and spontaneous sedimentation. The immunological diagnosis was performed using an ELISA with anti-S. stercoralis IgG. The cortisol levels were measured in serum samples by ELISA. The frequency of S. stercoralis infection in alcoholic patients was 23.5% (78/332), while in nonalcoholic patients, it was 5.4% (5/92) (p<0.05). The cortisol levels were higher in alcoholic than in nonalcoholic patients (p<0.05). However, among the alcoholic patients, the cortisol levels did not differ between S. stercoralis-infected and uninfected patients (p>0.05). As demonstrated in this work, 81.3% (26/32) of patients with a high parasite load, considered as more than 11 larvae per gram of feces, presented serum cortisol levels above the normal reference value (24 mg/dL). High endogenous cortisol levels in alcoholic patients were not associated to susceptibility to S. stercoralis infection, however once infected, this may lead to a high parasite load.

Giardia lamblia infection after pancreas-kidney transplantation

Infection is a common complication of solid organ transplantation. It is associated with an increased risk of acute cellular rejection and loss of graft function. The most common infections are due to bacteria and viruses, including transmission of cytomegalovirus from donor to recipient. In the past years, an increasing number of parasitic infections have been documented in transplant recipients. We describe the first reported case of intestinal Giardia lamblia transmission following simultaneous pancreas and kidney transplantation.

Transplantation in the tropics: lessons on prevention and management of tropical infectious diseases

Tropical infectious diseases (IDs) remain a rare complication in transplant recipients even in tropical settings, but this topic has become increasingly important during the last decade due to multiple factors. Interestingly, non-tropical countries report most of the experiences with tropical diseases. The reported experience from non-endemic regions, however, does not always reflect the experience of endemic areas. Most of the guidelines and recommendations in the literature may not be applicable in tropical settings due to logistical difficulties, cost, and lack of proven benefit. In addition, certain post-transplant prevention measures, as prophylaxis and reducing exposure risk, are not feasible. Nonetheless, risk assessment and post-transplant management of tropical IDs in tropical areas should not be neglected, and clinicians need to have a higher clinical awareness for tropical ID occurring in this population. Herein, we review the more significant tropical ID in transplant patients, focusing on relevant experience reported by tropical settings.

Diarrhea in solid-organ transplant recipients: a review of the evidence

OBJECTIVE

To provide a comprehensive review of the literature as it relates to diarrhea in solid organ transplant (SOT) recipients. In this article, we review the epidemiology, pathogenesis, clinical manifestations, diagnosis and management of diarrhea in SOT recipients and discuss recent advances and challenges.

METHODS

Two investigators conducted independent literature searches using PubMed, Web of Science, and Scopus until January 1st, 2013. All databases were searched using a combination of the terms diarrhea, solid organ transplant, SOT, transplant associated diarrhea, and transplant recipients. Articles that discussed diarrhea in SOT recipients were reviewed and relevant cross-references also read and evaluated for inclusion. Selection bias could be a possible limitation of the approach used in selecting or finding articles for this article.

FINDINGS

Post-transplant diarrhea is a common and distressing occurrence in patients, which can have significant deleterious effects on the clinical course and well-being of the organ recipient. A majority of cases are due to infectious and drug-related etiologies. However, various other etiologies including inflammatory bowel disease must be considered in the differential diagnosis. A step-wise, informed approach to post-transplant diarrhea will help the clinician achieve the best diagnostic yield. The use of diagnostic endoscopy should be preceded by exclusion of an infectious or drug-related cause of diarrhea. Empiric management with antidiarrheal agents, probiotics, and lactose-free diets may have a role in managing patients for whom no cause can be determined even after an extensive investigation.

CONCLUSIONS

Physicians should be familiar with the common etiologies that result in post-transplant diarrhea. A directed approach to diagnosis and treatment will not only help to resolve the diarrhea but also prevent potentially life-threatening consequences including loss of the graft as well. Prospective studies are required to determine the etiology of post-transplant diarrhea in different clinical and geographic settings.

Posterior reversible encephalopathy syndrome in a renal transplanted patient

Patient: Male, 28

Final Diagnosis: Posterior reversible encephalopathy syndrome

Symptoms: Headache • pain around umblical region • seizures • visual disturbances

Medication: Mycophenolate mofetil

Clinical Procedure: Treatment of parasitosis • antiepileptic treatment • control of hypertension • changing mycophenolate mofetil to everolimus

Specialty: Transplantology

Strongyloides stercoralis infection in an intestinal transplant recipient

Strongyloides stercoralis is a helminth in tropical and subtropical areas. It may cause latent infection and progress to Strongyloides hyperinfection syndrome, which is associated with a high mortality rate. Transplant recipients under the treatment of immunosuppressant agents are at risk of severe S. stercoralis infection. According to related literature, most cases of S. stercoralis infection after solid organ transplantation are caused by reactivation of latent infections in the recipients, whereas only a few are acquired from the donors. We report on an intestinal transplant recipient who had S. stercoralis infection diagnosed by a larva of this parasite found in the stool from the ileostomy stoma 1 month after transplantation. The donor was considered the source of the infection because the donor was from an endemic area and had marked eosinophilia, and the recipient had no contact history or clinical manifestations related to the S. stercoralis infection before transplantation. The patient was treated with ivermectin and exhibited no evidence of infection after 7 months.

Epidemiological aspects of strongyloidiasis in Brazil

The objective of this review was to outline an epidemiological profile of Strongyloides stercoralis by parasitological and serological diagnosis in inhabitants, and to associate this profile with different immunosupression situations, in Brazil, over 20 years (1990-2009). The occurrence of S. stercoralis using parasitological methods was 5·5%, being 4·8% in rural and 5·0% in urban areas, characterizing the country as hyperendemic. There was a diversity of techniques used as a diagnostic tool and only 39·1% of the studies presented results based on at least 1 specific method. The occurrence increased with age, being 12·1%, for those over 60 that suggests an epidemiological condition of concern for the elderly population. Of the seroepidemiological studies in the general population the mean positivity in serum samples was 21·7% and 29·2%, using an immunofluorescence antibody test and enzyme-linked immunosorbent assay (ELISA), respectively. The occurrence of strongyloidiasis in immunosuppressed individuals was 11·8% by parasitological methods and 19·5% using immunological methods. Considering that Brazil is a tropical country and that the character of chronicity and autoinfection of the parasite that can result in severe forms of hyperinfection or dissemination makes strongyloidiasis an important medically and socially neglected problem.

Duodenal villous atrophy: a cause of chronic diarrhea after solid-organ transplantation

Persistent diarrhea is commonly observed after solid organ transplantation (SOT). A few cases of mycophenolate mofetil (MMF)-induced duodenal villous atrophy (DVA) have been previously reported in kidney-transplant patients with chronic diarrhea. Herein, we report on the incidence and characteristics of DVA in SOT patients with chronic diarrhea. One hundred thirty-two SOT patients with chronic diarrhea underwent an oesophago-gastroduodenoscopy (OGD) and a duodenal biopsy after classical causes of diarrhea have been ruled out. DVA was diagnosed in 21 patients (15.9%). It was attributed to mycophenolic acid (MPA) therapy in 18 patients (85.7%) (MMF [n = 14] and enteric-coated mycophenolate sodium [n = 4]). MPA withdrawal or dose reduction resulted in diarrhea cessation. The incidence of DVA was significantly higher in patients with chronic diarrhea receiving MPA compared to those who did not (24.6% vs. 5.1%, p = 0.003). DVA was attributed to a Giardia lamblia parasitic infection in two patients (9.5%) and the remaining case was attributed to azathioprine. In these three patients, diarrhea ceased after metronidazole therapy or azathioprine dose reduction. In conclusion, DVA is a frequent cause of chronic diarrhea in SOT recipients. MPA therapy is the most frequent cause of DVA. An OGD should be proposed to all transplant recipients who present with persistent diarrhea.

Parasitic infections in solid organ transplant recipients

Parasitic infections are an uncommon but potentially severe complication in solid organ transplant (SOT) recipients. An increase in donors who have emigrated from tropical areas and more transplant recipients traveling to endemic areas have led to a rise in parasitic infections reported among SOT recipients. Clinicians should include these infections in their differential diagnosis and promote adherence to preventive measures in SOT recipients.

Strongyloides stercoralis hyperinfection transmitted by liver allograft in a transplant recipient

We describe a case of Strongyloides stercoralis hyperinfection in a liver allograft recipient 2.5 months after transplantation. The patient lives in Spain, which is not considered an endemic country for strongyloidiasis, and denied prior residence or travel to any known endemic area. The initial symptoms were fever and vomiting, and he subsequently developed a severe respiratory disease. An endoscopic biopsy of ulcerative lesions of the duodenum revealed massive mucosa infiltration by larvae and adult worms, which were also found in respiratory samples. The patient was successfully treated with combined therapy with albendazole and ivermectin. The strongyloides infection was transmitted by the liver allograft. The donor was from Ecuador and, retrospectively, his serum tested positive for S. stercoralis IgG antibodies. Additionally, the pancreas-left kidney allograft recipient from the same donor later developed an intestinal strongyloidiasis without hyperinfection syndrome. To our knowledge, this is the first confirmed case of S. stercoralis infection transmission from the same donor to two solid allograft recipients.

Strongyloidiasis in transplant patients

Strongyloides stercoralis is an intestinal nematode that can persist in the human host for decades after the initial infection and can progress to fulminant hyperinfection syndrome in immunocompromised hosts. We describe a patient who died of Strongyloides hyperinfection syndrome 2 months after orthotopic heart transplantation and discuss approaches to prevention, diagnosis, and treatment. Current practice guidelines recommend screening for and treatment of Strongyloides infection before transplantation, but physicians in the United States often miss opportunities to identify patients with chronic strongyloidiasis. Screening tests have limitations, and clinical suspicion remains an important component of the evaluation before transplantation. After immunocompromised patients develop hyperinfection syndrome, diagnosis is often delayed and mortality is high, so emphasis must be placed on screening and treatment before transplantation. We review current strategies for prevention, diagnosis, and treatment of chronic intestinal strongyloidiasis in patients who will undergo transplantation and discuss the clinical features and management of Strongyloides hyperinfection syndrome in transplant recipients.

Transplantation and tropical infectious diseases

The number of transplant recipients with tropical infectious diseases is growing due to increasing international travel and the rising number of transplants taking place in the tropics and subtropics. With increases in population migration, the prevalence of individuals infected with geographically restricted organisms also rises. There are three potential categories of tropical infections in transplant patients: (1) donor-related infections transmitted by the graft or through transfusion of blood products; (2) reactivation or recrudescence of latent infections in the donor recipient; and (3) de novo acquisition of infection in the post-transplant period through the traditional route of infection. We present an overall discussion of the association of parasitic (protozoa and helminths) and non-parasitic (viral, bacterial, and fungal) tropical infectious diseases and solid-organ and hematopoietic transplantation. We also suggest potential screening guidelines for some of these tropical infections.

[Recommendations before travelling for renal transplant patients]

Travel is now a reasonable objective of CKD patients after renal transplantation. However, immunosuppressive treatment makes them particularly susceptible to infections and may interfere with vaccinations and other drugs. Travel in countries with low health level should be strongly discouraged in the first six months after transplantation or following an acute event. Otherwise, specific consultations should be arranged to prepare the patient as soon as possible. Vaccinations should be started early before departure. Specific immunisations include vaccines against hepatitis A, typhoid, meningococcus and rabies in some cases. Living vaccines are formally contra-indicated. Particular attention should be paid for protection against insects because this is the only effective measure against diseases. In the case of malaria, it should be complemented by adapted chemoprophylaxis that should be started 15 days before the departure date. Advice on hygiene measures should be clarified because this can prevent numerous infections, especially of the digestive tract. Advice on the management of diarrhoea is essential, especially in terms of preventing dehydration. Finally, advice about transport and physical risks, especially those related to sun exposure, should also be addressed.

Unusual presentation of primary toxoplasmosis infection in a kidney-transplant patient complicated by an acute left-ventricular failure

Although primary toxoplasmosis is a rare event following kidney transplantation, it can be life threatening. This report describes this complication. The patient presented with high-grade fever, haemolytic anaemia and haemophagocytic-syndrome-related pancytopaenia. Toxoplasma gondii diagnosis was ascertained by blood and bone-marrow PCR assays. After 6 weeks with Clindamycin plus pyrimethamine therapies and despite negativation of T. gondii blood PCR assay, the patient developed left-ventricular failure. After adding sulfamethoxazole/ trimethoprim, ramipril, digoxine, bisoprolol and spironolactone, he progressively recovered. Anti-T. gondii therapy was continued for 6 months. Four years later he received a third kidney allograft: at that time anti-T. gondii antibodies had become negative. The outcome was uneventful despite immunosuppression but with inclusion of sulfamethoxazole/trimethoprim prophylaxis. More than 3 years after the third kidney transplantation the patient has had no toxoplasmosis reactivation. This case report highlights that T. gondii can be the cause of myocarditis in a renal transplant recipient.

Temporal and spatial distribution of Toxoplasma gondii differentiation into Bradyzoites and tissue cyst formation in vivo

During Toxoplasma gondii infection, a fraction of the multiplying parasites, the tachyzoites, converts into bradyzoites, a dormant stage, which form tissue cysts localized mainly in brain, heart, and skeletal muscles that persist for several years after infection. At this stage the parasite is protected from the immune system, and it is believed to be inaccessible to drugs. While the long persistence of tissue cysts does not represent a medical problem for healthy individuals, this condition represents a major risk for patients with a compromised immune system, who can develop recrudescent life-threatening T. gondii infections. We have investigated for the first time the dynamics and the kinetics of tachyzoite-to-bradyzoite interconversion and cyst formation in vivo by using stage-specific bioluminescent parasites in a mouse model. Our findings provide a new framework for understanding the process of bradyzoite differentiation in vivo. We have also demonstrated that complex molecules such as d-luciferin have access to tissue cysts and are metabolically processed, thus providing a rationale for developing drugs that attack the parasite at this developmental stage.