Regulatory T cells and Toll-like receptor 2 and 4 mRNA expression in infants with colic treated with Lactobacillus reuteri DSM17938

Regulatory T cells induce immune homeostasis and the expression of Toll like receptors (TLRs); subsequent inflammatory cytokine release may be involved. Recent studies have shown a microbial imbalance in the gut of colicky infants (with a prevalence of gram-negative bacteria, such as Escherichia coli), and accumulating evidence has shown the efficacy of a probiotic (Lactobacillus reuteri) in breastfed subjects, but the underlying mechanism remains undefined. The study enrolled 59 infants younger than 60 days, of whom 34 subjects had colic and 25 were healthy controls. With a double-blind, placebo-controlled randomised study performed in our unit from October 2016 to July 2017, infants with colic were randomly assigned to receive oral daily L. reuteri DSM17938 (1×108 cfu) or placebo for 28 days. Peripheral blood was collected to assess the expression of FoxP3, TLR2 and TLR4 mRNA using real-time TaqMan RT-PCR at baseline and after the study period. Our findings showed increased mRNA expression of the transcription factor forkhead box P3 (FoxP3) in infants treated with L. reuteri DSM 17938 for 28 days (P<0.009) and increased TLR2 and TLR4 mRNA expression in both treated and placebo subjects. After L. reuteri administration for 28 days in infants with colic, we observed a significant decrease in daily crying time (302.3±19.86 min/day on day 0 vs 76.75±22.15 min/day on day 28, P=0.001). This study provides evidence that the observed increase in FoxP3 expression and reduction in crying time might be responses to probiotic treatment, while the increase in TLR2 and TLR4 mRNA expression might be related to age. Exploiting these new findings may lead to an unprecedented level of therapeutic control over immune tolerance using probiotics.

HPyV6, HPyV7 and TSPyV DNA sequences detection in skin disease patients and healthy subjects

BACKGROUND

The discovery, from 2007, of eight new human polyomaviruses (HPyVs) has revived interest in the Polyomaviridae family and their association with human diseases and cancer. In particular, HPyV6 and HPyV7 were discovered in skin swabs of healthy donors and TSPyV was discovered in a heart transplant recipient affected by virus-associated Trichodysplasia Spinulosa (TS), a rare skin disease, exclusively found in immunocompromised patients.

OBJECTIVE

The presence of HPyV6, HPyV7 and TSPyV DNA in skin biopsies from patients affected by different skin diseases (cancers and inflammatory disorders) has been evaluated to confirm their skin tropism and the possible pathological association.

METHODS

DNA extracted was amplified with HPyV6, HPyV7 and TSPyV specific PCR real time on Taqman platform with standard profile.

RESULTS

HPyV7 and TSPyV sequences were not found in any skin specimen analysed. HPyV6, on the other hand, was detected in 30% of samples from healthy subjects vs. 14.3% of skin cancer patients and 2.9% of inflammatory disorders. HPyV6 sequences have been detected in primary cutaneous T-cell lymphoma (CTCL) patients (in 18.6% out of Mycosis Fungoides (MF) patients and in 16.7% out of CTCL not MF/SS(Sèzary syndrome) but have not been detected in primary cutaneous B-cell lymphoma (CBCL) patients.

CONCLUSION

Our preliminary data suggest that these three novel human polyomaviruses seem not to play a significant role neither in the pathogenesis of cutaneous malignancies nor in that of inflammatory disorders but, according to literature, can inhabit the skin. On the basis of our data regarding the HPyV6 DNA presence with decreasing percentages in healthy subjects, skin cancer and inflammatory disorders patients, it could be an intriguing matter to study if the activated innate immune response in inflammatory disorders can suppress the virus. Further investigations are needed to better understand their relationship with the human host and its innate immune system.

Combined measurement of serum DNA and urine VP1 messenger RNA in monitoring BK virus replication in kidney graft recipients

Evaluation of BK virus replication is a fundamental tool in the monitoring of renal transplant recipients. Herein, we investigated the role of urine VP1 messenger RNA (mRNA) quantification and combined measurement of serum DNA and urine VP1 mRNA in 428 kidney allograft recipients. BK viremia and viruria were detected in 24 (5.6%) and 54 (12.6%) patients, respectively. A diagnosis of BKV-associated nephropathy (BKVAN) was established in 2 patients, both within the first year posttransplantation. Based on urine VP1 mRNA measurement, BKV replication was observed in 10 (2.1%) patients, 2 of whom displayed BKVAN. Urine VP1 mRNA was detected in all cases in association with viremia except 5 and in all cases with viruria. No difference among VP1 mRNA levels was noted between the 2 BKVAN patients and the highest values in patients without BKVAN. The urine VP1 mRNA result by analysis using the operating characteristics was not superior to viremia, despite the improvement obtained with the combined measurement of viremia (cut-off, 16,000 copies/mL) and urine VP1 mRNA (>10,000 copies/10(3) cells). In conclusion, VP1 mRNA measurements may complement viremia and viruria to monitor BKV replication, although its use is limited by its technical complexity in comparison with DNA detection.

Detection of the novel variant of influenza virus A/H1N1v in bronchoalveolar lavage of adult hospitalized patients during the 2009/2010 winter season

AIM

The aim of this study was to report most recent data regarding the occurrence of influenza A virus H1N1v in the lower respiratory tract from a cohort of hospitalized adult patients during the winter season 2009/2010 and investigated the main clinical features and outcomes.

METHODS

A total of 130 consecutive BAL specimens (collected from October 2009-March 2010) of 101 patients were retrospectively analyzed for influenza A virus H1N1v positivity using a commercial kit.

RESULTS

Overall, 19/130 (14.6%) BAL specimens from 17/101 (16.8%) patients were positive for the novel influenza A H1N1v virus. H1N1v resulted significantly more prevalent in immunocompetent subjects. As regards clinical features, H1N1v resulted more prevalent in respiratory insufficiency or acute respiratory illness. Thirteen patients died during the analytic period; three of them (23.1%) resulted positive to H1N1v but no direct association has been made.

CONCLUSION

Our cohort study of influenza A H1N1v detection in BAL from hospitalized adult patients confirms the overall moderate clinical impact of this virus, as reported in most reports worldwide. It remains to be evaluated the role of reassortment with influenza virus strains circulating in the winter season 2010/2011 and its potential pathogenicity.

Prevalence of polyomaviruses BK, JC, SV40, KI, and WU in non-malignant tonsil specimens

AIM

The recently described polyomaviruses KI and WU have been detected in respiratory samples, stools, tonsils, and blood, particularly in immunocompromised conditions, although little is known about tissue tropism. Herein we investigated the occurrence of KIV and WUV in non-malignant tonsillar specimens by Real-time quantitative PCR; the presence of polyomaviruses BK, JC and SV40-DNA was also evaluated.

METHODS

Twenty-nine non-malignant tonsil specimens obtained from children and adults admitted for tonsillectomy were prospectively studied. Real-time quantitative TaqMan PCR for polyomaviruses KI, WU, BK, JC, and SV40 were performed.

RESULTS

KI-DNA was positive in 2/29 tonsillar specimens (6.9%), while BK- DNA, JC-DNA, SV-40 DNA, and WU-DNA sequences were not identified.

CONCLUSION

Few studies have investigated the prevalence of polyomaviruses in tonsil specimens, with varying results, and data are particularly scant as regards the newly discovered KIV and WUV. Two major questions remain to be definitely answered at this regard: the possibility that human tonsils represent the initial site of infection and/or a latency site and the biological and clinical meaning of KIV and WUV in different contexts and groups of patients, in that it is not clear whether they are simple bystanders or play a role in tonsil disease.

Prevalence and clinical impact of polyomaviruses KI and WU in lung transplant recipients

The newly discovered polyomaviruses KI and WU (KIV and WUV) were isolated from secretions of patients with respiratory symptoms as well as in blood, spleen, lymphoid tissues, and stools, especially in immunocompromised conditions. The aim of this work was to evaluate the prevalence of KIV and WUV in bronchoalveolar lavage (BAL) from lung transplant recipients. We also examined potential correlations between these viruses and occurrences of pneumonia, acute respiratory insufficiency, or other acute respiratory conditions and acute rejection episodes. Discharge diagnosis was based on the International Classification of Diseases-Italian version 2002, based on the 9th-revision clinical modification. A rejection episode was diagnosed by transbronchial lung biopsy in accordance with the 2007 International Society for Heart and Lung Transplantation Working Formulation. Overall, we analyzed 53 BALs obtained from 24 transplant recipients. Positive polymerase chain reaction results were observed in 6 samples (11.3%) from 6 patients (25%), versus 7 samples (13.2%) from 7 patients (29.2%) for KIV and WUV, respectively. Regarding the diagnosis of pneumonia, the prevalence was 22.2% and 33.3% for KIV and WUV, respectively. In cases of acute respiratory insufficiency or other acute respiratory conditions, 2 out of 9 samples were positive for KIV (22.2%) and 4 out of 9 for WUV (44.4%). An Acute rejection episode (ARE) was diagnosed in 7 instances among 6 lung transplant patients: The corresponding BAL specimens showed positive results for KIV in 3 out of 7 (42.8%) cases with ARE vs 3 out of 46 (6.5%) without an ARE (P < .05), and for WUV in 3 out of 7 (42.8%) vs 4 out of 46 (8.7%) (P < .05), respectively. Although the small number of specimens limits the statistical analysis, our results showed a higher prevalence of WUV compared with KIV. The compromised pulmonary environment in the lung allograft may cause reactivation of these viruses. Their roles in this context need to be further evaluated.

Immunosuppressive agents and bone disease in renal transplant patients with hypercalcemia

Renal transplantation is the definitive treatment for many metabolic abnormalities of uremic patients, although it is only partially effective for renal osteodystrophy, which may interact with posttransplant renal osteopathy. Osteopenic-osteoporotic syndrome represents, together with fractures secondary to osteoporosis and osteonecrosis, the bone complication most related to renal transplantation. Several factors contribute to the pathogenesis of posttransplantation osteoporosis, particularly immunosuppressive treatment. In this study, we evaluated the prevalence of factors related to posttransplant renal osteopathy and the clinical impact of immunosuppressive protocols. We studied 24 renal transplant recipients with hypercalcemia. Glomerular filtration rate was >50 mL/min. Mean age, time on dialysis, and time from transplantation were 49.6, 5.4, and 6.9 years, respectively. We evaluated serum and urine calcium and phosphorus, calcitonin, parathormone, bone-specific alkaline phosphatase, osteocalcin, urine deoxypyridinoline, telopeptide of type 1 procollagen, 1,25-(OH)(2) and 25-OH vitamin D, parathyroid ultrasound, and computerized bone mineralometry. The combination of sirolimus and steroids resulted in the most disadvantageous outcomes regarding alkaline phosphatase and mineralometry. Calcineurin inhibitors did not significantly influence bone metabolism markers; mycophenolate mofetil evidenced no effect on bone. According to the literature, steroids account for the abnormalities found in our patients and in severe osteopenia. Several factors may contribute to the development of osteoporosis and fractures in transplantation patients, although they are overcome by the prominent effect of steroids. In patients at high risk of osteoporosis, steroid-free therapy should be considered. Everolimus is indicated for diseases with bone loss. Combined therapy with everolimus and mycophenolic acid without cyclosporine and steroids, seemed to be particularly indicated. Prophylactic treatments should be commenced early. No single marker was useful to diagnose posttransplant renal osteopathy. The definitive diagnosis should be made by bone biopsy during transplantation, and noninvasive procedures, such as densitometry and evaluation of biologic markers, may be useful during follow-up.

Herpesviruses detection by quantitative real-time polymerase chain reaction in bronchoalveolar lavage and transbronchial biopsy in lung transplant: viral infections and histopathological correlation

The monitoring of herpesvirus infection plays a central role in lung transplantation (LT). Herein we evaluated the prevalence of human cytomegalovirus (HCMV), human herpesvirus-6 (HHV-6), human herpesvirus-7 (HHV-7), and Epstein-Barr Virus (EBV) DNA in bronchoalveolar lavage (BAL) and transbronchial biopsy (TBB) specimens from LT patients. We associated the findings with the occurrence of interstitial pneumonia, acute rejection, or organizing pneumonia. Viral DNA was detected using real-time polymerase chain reaction (PCR) on 76 paired samples (BAL and TBB) from 27 patients who were receiving a universal combined prophylaxis (cytomegalovirus [CMV] immunoglobulin [Ig] + gancyclovir or valgancyclovir). Histopathological analysis was performed in accordance with the International Society for Heart and Lung Transplantation (ISHLT) criteria. Overall, HCMV results were positive in 25/76 (32.9%) specimens (BAL and/or TBB); HHV-6 in 16 (21.1%); HHV-7 in 40 (52.6%); and EBV in 13 (17.1%). Interstitial pneumonia was diagnosed in 6/76 (7.9%) cases: 5 (83.3%) were positive to HCMV (combined specimens; P < .0001); 5 (83.3%) to HHV-7; and 2 (33.3%) to EBV. An acute rejection episode was diagnosed in 19/76 (25%) cases: 7 (36.8%) were positive to HCMV; 5 (26.3%) to HHV-6; 10 (52.6%) to HHV-7, and 3 (15.8%) to EBV. No significant association was observed between virus detection or load and acute rejection. Organizing pneumonia was diagnosed in 4/76 (5.3%) cases: 1 (25%) positive to HCMV; 4 (100%) to HHV-6 (P < .05); 2 (50%) to HHV-7; and none to EBV. In conclusion, the prevalence of HCMV tended to be lower than that reported in the literature, confirming the importance of universal combined prophylaxis. HCMV was a relevant agent for interstitial pneumonia; although the small numbers limit the statistical analysis, our data did not support an association between herpesviruses and acute rejection episodes, whereas the role of HHV-6 in the pathogenesis of organizing pneumonia deserves further study. Viral detection on TBB could represent an adjunctive tool to complement that on BAL.

Lower respiratory tract viral infections in hospitalized adult patients

AIM

The epidemiology of lower respiratory tract (LRT) viral infections in adults is probably underestimated and the high frequency of multiple viral infections complicates the evaluation of the possible role of the single viruses. The aim of this study was to investigate the clinical epidemiology and impact of respiratory viral pathogens, in particular of those singularly detected, in bronchoalveolar lavage (BAL) specimens from hospitalized adult patients.

METHODS

A panel for the detection of 16 respiratory viruses was used to prospectively evaluate 324 consecutive specimens obtained from 219 patients over a full-year period.

RESULTS

Two-hundred-twenty-one specimens (68.2%) were positive for at least one virus, 119/324 (36.7%) to a single viral agent. The most commonly detected viruses were herpesviruses HHV-7 (26.2%), human cytomegalo-virus (HCMV, 22.2%), HHV-6 (19.8%), EBV (12.7%), enteroviruses and rhinoviruses (both 11.7%), parainfluenza viruses (4.9 %), and metapneumovirus (4.0%). Human cytomegalo-virus was significantly more prevalent as single viral pathogen with a viral load >105 copies/ml associated to pneumonia in solid organ transplant recipients. Other viral pathogens might account for some cases of pneumonia or respiratory insufficiency, although multiple infections were common.

CONCLUSIONS

The use of a comprehensive diagnostic panel for respiratory viral infections may be useful to clarify the epidemiology and clinical impact of viral pathogens in hospitalized adult patients. The occurrence of multiple infections is a common finding and results should be interpreted taking into account the clinical context as well as viral load and the biological characteristics of each virus.

Circulating CD4+CD25 bright FOXP3+ T cells are up-regulated by biological therapies and correlate with the clinical response in psoriasis patients

BACKGROUND

Regulatory T-cell (T(reg)) modulation is one of the potential mechanisms of anti-tumour-necrosis-factor biological agents. However, literature data on psoriasis patients are lacking.

OBJECTIVE

To analyse the circulating CD4+CD25(bright)FOXP3+ subset in 30 patients with psoriasis vulgaris/arthropathic psoriasis treated with biologicals and to investigate its relationship with the clinical response.

METHODS

The CD25(bright)FOXP3+ expression within the CD4+ subset was determined by multi-parameter flow cytometry at baseline and during treatment. FOXP3 mRNA expression was analysed by real-time reverse transcription PCR.

RESULTS

A response was obtained in 16/17 patients (91.1%) with increased CD25(bright)FOXP3+ values and in only 3/11 patients (27.3%) who showed a CD25(bright)FOXP3+ decrease during biological treatment (p = 0.0001). Responders showed significantly higher values than did non-responders as from the first 2 months of treatment (p = 0.0032). A significantly higher posttreatment expression of mRNA FOXP3 was observed in responders compared to non-responders.

CONCLUSION

Biological drugs induce a circulating T(reg) up-regulation in a significant percentage of patients; such an increase is an early predictive marker of response.

Human herpesvirus 7 detection by quantitative real time polymerase chain reaction in primary cutaneous T-cell lymphomas and healthy subjects: lack of a pathogenic role

BACKGROUND

Primary cutaneous T-cell lymphomas (CTCLs) are a heterogeneous group of lymphomas where the tumour population emerges within a multiple subclone pattern. Mycosis fungoides (MF) and Sézary syndrome (SS) are characterized by the expansion of clonal CD4+/CD45RO+ memory T cells. Lymphomatoid papulosis (LyP) is a chronic, lymphoproliferative disorder included in the CD30+ primary CTCL spectrum. Several studies have suggested a role of viral infection for super-antigenic activation of T lymphocytes; however, evidence of their association with CTCLs is still lacking. Human herpesvirus (HHV) 7 is a CD4+ T-lymphotropic herpesvirus; its restricted cellular tropism and the ability to induce cytokine production in infected cells could make it an important pathogenic cofactor in lymphoproliferative disorders.

OBJECTIVES

To investigate the presence of HHV7 DNA on CTCL and healthy skin donors (HD).

METHODS

We used quantitative real time polymerase chain reaction to evaluate the potential pathogenic role of HHV7.

RESULTS

Twenty-seven of 84 (32.1%) HD were positive for HHV7 DNA. Twenty-one of 148 (14.2%) patients with CTCLs were positive for HHV7 DNA: nine of 39 (23.1%) SS, six of 14 (42.9%) CD30+ CTCLs and six of 24 (25.0%) LyP, and HHV7 DNA was negative in all 71 patients with MF.

CONCLUSIONS

These results seem to exclude a pathogenic role of HHV7 in CTCLs, suggesting the possibility of skin as a latency site.

Monitoring of human Cytomegalovirus infection by antigenemia and viremia in the first 100 days following renal transplantation and relation to antiviral strategies

AIM

Human Cytomegalovirus (HCMV) is a relevant pathogen in transplant recipients, particularly in the first three months post-transplantation. The use of antiviral prophylaxis and pre-emptive therapy is able to reduce incidence of HCMV infection and disease. The incidence of HCMV infection and disease in renal transplant recipients in the first 100 days post-transplantation was investigated, in relation with HCMV serological matching and therapeutic management.

METHODS

Incidence of HCMV infection in the first 100 days post-transplantation was evaluated by pp65-antigenemia in 165 patients on a total number of 1241 clinical samples. Patients were divided in four groups according to donor/recipient serological matching: D(-)/R(-) (low risk of HCMV disease), D(-)/R+ and D+/R+ (intermediate risk) and D+/R(-) (high risk). Antiviral strategy (prophylaxis in high risk group; pre-emptive therapy in intermediate risk group, no therapy in low risk group) and immunosuppressive protocol were recorded.

RESULTS

Incidence of antigenemia-positivity was as follows: 0/3 D(-)/R(-) patients; 59/130 (45.4%) D+/R+; 5/16 (31.3%) D(-)/R+; 4/16 D+/R(-). No significative difference was found between the four groups in terms of incidence of antigenemia-positivity in the first 100 days following transplantation. Antigenemia values >50 pp65-positive/2x10(5) peripheral blood leukocytes (used to start pre-emptive therapy) were present in 18/130 (13.8%) D+/R+; 1/16 (6.2%) D+/R(-); 0/16 D(-)/R+. Viral kinetics in patients with HCMV infection was described.

CONCLUSION

No significative difference was found in terms of incidence of HCMV infection in the first 100 days post-transplantation in relation to immunosuppressive protocol and serological matching, suggesting the appropriateness of antiviral strategies and viral monitoring adopted in this setting.

Human polyomavirus BK in patients with lupus nephritis: clinical and histological correlations

Polyomavirus BK (BKV) reactivation can occur in immunodeficient patients. Few studies on BKV infection in patients with systemic lupus erytematosus (SLE) nephritis are available. Aim of this study was to analyse the prevalence of BKV infection by quantifying viral load and to investigate the association with clinical and histological parameters indicating duration, type and activity of SLE.BKV-DNA was evaluated by polymerase chain reaction in serum (sBKV) and urine (uBKV) specimens from 40 patients with SLE nephritis and 29 healthy controls. Renal function, urinary activity, clinical index of SLE activity [SLE Disease Activity Index (SLEDAI) score], CD4+/CD8+ ratio, histological classes and duration of SLE nephritis were compared according to the BKV-DNA-positivity.sBKV was present in 15% of SLE patients and in 13.8% of controls; uBKV in 32% of SLE patients and in 17.2% of controls. There was no significant difference in terms of kidney function, urinary activity, SLEDAI score, presence of anti-dsDNA antibodies, CD4+/CD8+ ratio and BKV viremia and/viruria, as well as there was no significant correlation between SLEDAI score, anti-dsDNA antibodies titers and median viral load. Duration of nephropathy tended to be shorter in patients with BKV viremia and/or viruria; proteinuria/creatininuria ratio tended to be higher in patients with positive sBKV and uBKV. BKV-DNA-positivity tended to be more frequent in patients treated with an immunosuppressive agent versus those on steroid treatment. Reactivation of BKV infection can occur in patients with SLE, although prevalence data do not significantly differ from those obtained in the control group. The trend toward an association between BKV infection and degree of proteinuria and less duration of SLE nephritis could indicate a major susceptibility to develop BKV infection in more active phases of the disease. The role of BKV reactivation in terms of clinical parameters and histological pattern, as well as the role of therapeutic protocols in the onset of BKV reactivation and, conversely, the therapeutic implication of BKV reactivation in SLE patients remain to be defined and should be addressed in further studies on a larger number of patients.

Rapid shell vial culture for the detection of respiratory viruses from bronchoalveolar lavage in immunocompromised patients

AIM

Viral lower respiratory tract infections (LRTI) are an important cause of morbidity in immunocompromised patients. The aim of this study was to evaluate the clinical impact of rapid shell vial cultures from bronchoalveolar lavage (BAL).

METHODS

Sixty-seven BAL samples from 46 patients have been retrospectively examined: 51 from 31 transplant recipients and 16 from 15 immunocompromised patients. BAL were inoculated on human embryonic lung fibroblasts and VERO cells to isolate the following viruses: cytomegalovirus (CMV), herpesviruses, varicella-zoster virus, respiratory syncytial virus, adenovirus, Influenza viruses A and B and Parainfluenza viruses. Clinical, microbiological, laboratory, and radiological data were collected.

RESULTS

A LRTI was present in 56.7% of cases: viral 40.3%, bacterial and/or fungal 23.9%, and mixed 7.5%. CMV accounted for 92.6% of viral LRTI. The prevalence of viral infections did not differ between symptomatic and asymptomatic patients; only bacterial and/or fungal infections were significantly more prevalent in symptomatic patients. No clinical, radiological or laboratory feature was significantly associated with the presence of a viral LRTI. In lung transplant recipients the rate of CMV infection was 50%. The result of BAL suggested commencement of antiviral chemotherapy in 25/67 episodes.

CONCLUSION

Rapid shell vial culture and immunofluorescence techniques from BAL could play an important role in the clinical management of immunocompromised subjects.

The hazardous burden of Herpesviridae in inflammatory bowel disease: the case of refractory severe ulcerative colitis

BACKGROUND

Herpesviridae infection or spread may be a hazard in immunodepressed patients. In the field of inflammatory bowel disease, refractory severe ulcerative colitis is a challenging condition, closely associated to immunosuppression both for inanition due to the disease activity and for immunosuppressive treatments. Cytomegalovirus (CMV) has been proposed as a major cause of refractoriness, while other Herpesviridae may be a risk factor in the long-term follow-up.

AIM OF THE STUDY

To evaluate the positivity rates of CMV, Epstein-Barr (EBV) and Human herpes virus-8 (HHV8) in a consecutive group of ulcerative colitis patients who underwent colectomy for refractoriness to medical treatment compared to a control group, using state of the art methods.

PATIENTS AND METHODS

Colonic specimens from 24 consecutive patients with ulcerative colitis submitted to colectomy for refractoriness and from 20 controls (submitted to colectomy for colorectal cancer) were studied. Standard histology and immunohistochemistry (IHC) for CMV and specific polymerase chain-reaction (PCR) for CMV, EBV and HHV8 were carried out.

RESULTS

Regarding CMV, 1 case (4%) was positive at histology and IHC, whereas 3 cases (13%) were positive at PCR, compared to none in the control group (p=0.239). For EBV 2 cases (8%) and 2 controls (10%) were positive at PCR. None of the cases or of controls was positive for HHV8. The only clinical characteristic independently associated to CMV positivity was the white blood cell count at admission, higher among CMV positive patients (p<0.001). At the end of the post-surgery follow-up (median 7.3 years) none of the CMV positive cases experienced pouchitis, compared to 3/21 (14%) of the CMV negative cases (p=1.000).

DISCUSSION

Our data suggest that CMV is uncommon (13%), even though PCR techniques, considered to be the most sensitive tools, were used for virus detection and the study population is made by highly selected patients with definite refractoriness. EBV and HHV8 may represent a theoretical risk of immunosuppressive therapy because of their potential role as cancer triggers; however in our study, results seem to be reassuring that UC patients undergoing immunosuppressive therapy are not exposed to an excessive risk of viral infection.

Development of a quantitative-competitive PCR for quantification of human cytomegalovirus load and comparison with antigenaemia, viraemia and pp67 RNA detection by nucleic acid sequence-based amplification

AIM

The human cytomegalovirus (HCMV) is an important pathogen in immunocompromised patients, such as transplant recipients. The use of sensitive and rapid diagnostic assays can have a great impact on antiviral prophylaxis and therapy monitoring and diagnosing active disease. Quantification of HCMV DNA may additionally have prognostic value and guide routine management. The aim of this study was to develop a reliable internally-controlled quantitative-competitive PCR (QC-PCR) for the detection and quantification of HCMV DNA viral load in peripheral blood and compare it with other methods: the HCMV pp65 antigenaemia assay in leukocyte fraction, the HCMV viraemia, both routinely employed in our laboratory, and the nucleic acid sequence-based amplification (NASBA) for detection of HCMV pp67-mRNA.

METHODS

Quantitative-competitive PCR is a procedure for nucleic acid quantification based on co-amplification of competitive templates, the target DNA and a competitor functioning as internal standard. In particular, a standard curve is generated by amplifying 10(2) to 10(5) copies of target pCMV-435 plasmid with 10(4) copies of competitor pCMV-C plasmid. Clinical samples derived from 40 kidney transplant patients were tested by spiking 10(4) copies of pCMV-C into the PCR mix as internal control, and comparing results with the standard curve.

RESULTS

Of the 40 patients studied, 39 (97.5%) were positive for HCMV DNA by QC-PCR. While the correlation between the number of pp65-positive cells and the number of HCMV DNA genome copies/mL and the former and the pp67mRNA-positivity were statistically significant, there was no significant correlation between HCMV DNA viral load assayed by QC-PCR and HCMV viraemia.

CONCLUSIONS

The QC-PCR assay could detect from 10(2) to over 10(7) copies of HCMV DNA with a range of linearity between 10(2) and 10(5) genomes.

Development and utilization of a quantitative polymerase chain reaction assay to evaluate human polyomavirus JC DNA load

AIM

Quantitative polymerase chain reaction (PCR) analysis to evaluate virus load in comparison with the patient's base-line virus levels would be an optimal diagnostic approach to monitoring human polyomavirus infections and to investigate their possible involvement in the onset of nephropathy in this patient group. Studies on the correlation between viral burden and renal disease have pointed to the incidence of JC virus (JCV) related progressive multifocal leukoencephalopathy (PML) occurring in renal and haematopoietic stem cell transplant recipients.

METHODS

We developed a reliable internally-controlled quantitative PCR assay to measure JCV-DNA in fluid samples of urine, serum and cerebrospinal fluid (CSF) by densitometric analysis of the amplification products. The assay was also used to evaluate the JCV load in CFS samples from patients with suspected demyelinating syndrome and in urine and serum samples from healthy subjects and renal transplant recipients.

RESULTS

All CSF samples from the 51 patients with suspected demyelinating syndrome tested JCV-DNA negative: none of them had a diagnosed PML. Analysis of the prevalence of JCV-viruria and JCV-viraemia confirmed our previous data. JCV-viruria was detected in 17% of renal transplant recipients and 26.6% of healthy controls; JCV-viraemia was found in 3.4% of transplant patients and 0% in controls. Noteworthy was a lower prevalence of JCV-viraemia in the 116 (3.4%) renal transplant patients than the prevalence previously reported for the 51 (11.8%) patients with suspected demyelinating syndrome. The mean viral load of viruria was much higher in the healthy controls than in the transplant recipients [104020 DNA copies/mL (DS+/-62284) vs 4136 DNA copies/mL (DS+/-77371)].

CONCLUSIONS

The quantitative PCR assay developed in our lab offers in 2 h time a reliable true quantification of viral DNA by densitometric analysis of the amplification product. To check for the possible presence of potential Taq polymerase inhibitors an internal control (the homemade pJCV-C plasmid) is used. The relation between polyomavirus infections and their possible involvement in post-transplant pathologies need further investigation. It would be useful to monitor the JCV-DNA load in urine and serum from more renal transplant recipients, including patients with nephropathy or active graft rejection over a longer period of time.

Co-detection and discrimination of JCV and BKV DNA by duplex nested-PCR in renal transplant recipients

AIM

Several studies have disclosed a correlation between human polyomavirus BK (BKV) and interstitial nephritis in renal transplant recipients. It has recently been hypothesized that some cases of nephropathy may be associated with human polyomavirus JC (JCV).

METHODS

In this paper we describe the development of duplex nested-PCR assay which allows the simultaneous detection and discrimination of genomic sequences of JCV and BKV ''large T antigen'', resulting in amplicons of 150 bp and 278 bp, respectively. Thus, the presence of JCV and BKV DNA in urine and serum samples from 51 renal transplant recipients and 29 healthy controls was investigated and related to immunosuppressive regimens and renal function.

RESULTS

The comparison between the incidence of the of BKV and/or JCV infections (detected by viruria and/or viraemia) in renal transplant recipients and the control group revealed a highly significant increase of the incidence of BKV infection in immunosuppressed patients vs healthy subjects (62.7% vs 27.6%; p=0.005). In particular, we found a significant increase of BKV-DNA viruria in renal transplant recipients vs healthy subjects (49% vs 17.2%; p=0.01), in agreement with the BKV urinary shedding in renal transplant recipients of the literature (5-45%).

CONCLUSION

The nested-PCR technique is a valid diagnostic tool to detect viral presence in urine and its systemic diffusion. Our assay links the high sensitivity of nested amplification with the simultaneous detection and discrimination of genomic sequences of JC and BK polyomaviruses and thus provides a handy, rapid and sensitive means for DNA analysis of large numbers of samples.

Epstein Barr viral load monitoring by quantitative PCR in renal transplant patients

Post-transplant lymphoproliferative disorders (PTLD), ranging from lymphoid hyperplasia to clonal malignancy, are a severe complication arising in solid organ transplant patients. Their reported incidence ranges from 1 to 20%, according to factors such as type of transplanted organ and the age of recipients. A strong correlation between Epstein Barr virus (EBV) infection, the grade and type of immunosuppression and the development of PTLD has been recognized. The detection and quantification of EBV-DNA load in peripheral blood have been utilized as prognostic markers for the development of PTLD, showing a correlation between high levels of EBV-DNA in the blood and the development of PTLD. In this study, we monitored EBV viral load monthly in 15 renal transplant recipients for six months. The number of EBV-DNA copies was measured in peripheral blood mononuclear cells (PBMC) and serum samples by a quantitative PCR protocol developed in our laboratory that employes a previous screening of samples containing a significant number of viral DNA copies (> or =1000 copies/10(5) PBMC or 100 microl serum) by semi-quantitative PCR followed by a precise quantification of the only significant samples by quantitative-competitive (QC)-PCR. Our 15 renal transplant patients neither developed PTLD nor had recurrent acute illnesses or acute graft rejections during the study. The results obtained in the monthly follow up of EB viral load in PBMC samples confirmed its fluctuation in asymptomatic patients reported in literature. In particular, 5/14 (35.7%) of EBV seropositive patients had an EBV-DNA load equal to 1000 EBV copies /10(5) PBMC (roughly corresponding to 10.000 copies/microg PBMC DNA), and 1/14 (7.1%) reached 5000 EBV copies /10(5) PBMC (roughly corresponding to 50.000 copies/microg PBMC DNA), at least once in our study. In the EBV seronegative patient, EBV-DNA in PBMC samples was always undetectable (less than 100 DNA copies/10(5) PBMC). EBV-DNA load in all serum samples was less than threshold value of our quantification protocol (<100 DNA copies/100 microl serum), supporting the literature data. With regard to immunosuppressive treatment, 66.7% of the six patients in whom EBV load reached values equal to or higher than 1000 DNA copies/10(5) PBMC, were on FK506 whereas only 33.3% of them were on CyA. In conclusion, further investigations are needed to better understand the role of EBV infection in the pathogenesis of PTLD in immunosuppressed patients. Given the high positive predictive value of EB viral load in peripheral blood for diagnosis of PTLD reported by several authors, and the described absence of correlation between the serological evidence of EBV reactivation and EB viral load, EBV viral load measurement in PBMC and serum samples using quantitative PCR techniques is a powerful diagnostic tool to monitor transplanted patients at risk to develop PTLD.

B19 virus infection in renal transplant recipients

BACKGROUND

B19 virus infection with persistent anaemia has been reported in organ transplant recipients. Detection of B19 virus DNA in serum is the best direct marker of active infection.

OBJECTIVE

The present study evaluated the incidence and clinical role of active B19 virus infection in renal transplant recipients presenting with anaemia.

STUDY DESIGN

Forty-eight such recipients were investigated by nested PCR on serum samples. The controls were 21 recipients without anaemia. Active HCMV infection was also investigated as a marker of high immunosuppression.

RESULTS AND CONCLUSIONS

In 11/48 (23%) patients B19 virus DNA was demonstrated in serum versus only 1/21 (5%) of the controls. Ten of these 11 patients had already been seropositive at transplantation and active infection occurred in eight of them during the first 3 months after transplantation. The remaining patient experienced a primary infection 9 months after transplantation. Eight (73%) of these 11 patients displayed a concomitant HCMV infection and four (36%) showed increasing serum creatinine levels but none developed glomerulopathy; 3/11 (27%) recovered spontaneously from anaemia whereas 8/11 (73%) needed therapy. In conclusion, the relatively high occurrence (23%) of B19 virus infection in patients presenting with anaemia, suggests that it should be considered in the differential diagnosis of persistent anaemia in renal transplant recipients. Presence of the viral DNA should be assessed early from transplantation and the viral load should be monitored to follow persistent infection and better understand the relation between active infection and occurrence of anaemia, and to assess the efficacy of IVIG therapy and/or immunosuppression reduction in clearing the virus.

[Epstein Barr viral load monitoring in mononuclear lymphocytes and serum of renal transplant recipients using a quantitative PCR protocol]

BACKGROUND

Post-transplant lymphoproliferative disorders (PTLD), ranging from lymphoid hyperplasia to clonal malignancy, are severe complications arising in solid organ transplant patients; their reported incidence ranges from 1 to 20%, according to factors such as type of transplanted organ and age of recipients. A strong correlation between Epstein-Barrvirus (EBV) infection, the grade and type of immunosuppression and the development of PTLD has been recognized. The detection and quantification of EBV-DNA load in peripheral blood have been utilized as prognostic markers for the development of PTLD, showing a correlation between high levels of EBV-DNA in the blood and the development of PTLD. In this study, we monthly monitored EBV viral load in 15 renal transplant recipients for six months. The number of EBV-DNA copies was measured in peripheral blood mononuclear cells (PBMC) and serum samples by a quantitative PCR protocol developed in our laboratory.

METHODS

Our EBV-DNA quantification protocol employs a previous screening of samples containing a significant number of viral DNA copies (>=1000 copies/105 PBMC or 100 mL serum) by semi-quantitative PCR followed by a precise quantification of the only significant samples by quantitative-competitive (QC)-PCR.

RESULTS

Our 15 renal transplant patients neither developed PTLD nor had recurrent acute illnesses or acute graft rejections during the study. The results obtained in the monthly follow up of EB viral load in PBMC samples confirmed its fluctuation in asymptomatic patients reported in the literature. In particular, 5/14 (35.7%) of EBV seropositive patients had an EBV-DNA load equal to 1000 EBV copies /105 PBMC, and 1/14 (7.1%) reached 5000 EBV copies /105 PBMC at least once in our study. In the EBV seronegative patient, EBV-DNA in PBMC samples was always undetectable (less than 100 DNA copies/105 PBMC). EBV-DNA load in all serum samples was less than threshold value of our quantification protocol (<100 DNA copies/100 mL serum). With regard to the immunosuppressive treatment, it should be noted that 66.7% of the six patients in whom EBV load reached values equal to or higher than 1000 DNA copies/105 PBMC, were on FK506 whereas only 33.3% of them were on CyA.

CONCLUSIONS

Since the high positive predictive value of EB viral load in peripheral blood for diagnosis of PTLD reported by several Authors, and the described absence of correlation between the serological evidence of EBV reactivation and EB viral load, EBV viral load measurement in PBMC and serum samples using quantitative PCR techniques is a powerful diagnostic tool to monitor transplanted patients at risk of developing PTLD.

[Polyomavirus BK nephropathy in renal transplant: 2 cases with different clinical expressions and review of the literature]

INTRODUCTION

Polyomavirus BK nephropathy is emerging as a significant cause of interstitial nephritis and allograft dysfunction (1-2).

CASE REPORT

Two patients with renal transplants from cadaveric kidneys were treated with Tacrolimus plus Mycophenolate Mofetil (MMF) and Cyclosporine plus MMF, respectively. Their renal function gradually deteriorated eight to twelve months after the transplant. The renal biopsy of the first patient showed signs of significant interstitial tubulite, which necessitated the anti-rejection therapy with intravenous steroid pulses. After the pulses there was an additional dramatic increase in plasmatic creatinine, which suggested a revaluation of the kidney biopsy because of suspected Polyomavirus BK (BKV) nephropathy. In fact, after a more careful review, the suspicion of BKV infection was confirmed by the presence of intranuclear inclusions of tubular epithelium cells and marked denudation of the tubular basal membrane. The subsequent screening in both cases confirmed the presence of decoy cells in the urine, while the immunohistochemical analysis of the renal biopsy was strongly positive for the SV40 antigen. Our diagnosis was that of interstitial nephritis due to Polyomavirus BK that, in the first patient, was expressed by more aggressive clinical progress, probably due to enhanced immunosuppression from incorrect diagnosis of the interstitial rejection. The pre-transplant clinical outcome of the first patient was characterised by proteinuric nephropathy without any histological confirmation. Furthermore, we observed abundant pre-transplant residual diuresis and glucose intolerance. All these elements led us to hypothesise that native kidneys could have a fundamental role as viral reservoirs.

CONCLUSION

Even though we reconfirm the decisive role of the immunosuppressive therapy and of the donor s kidney as the fundamental causes of Polyomavirus reactivation, we believe that it cannot be the result of a possible active role by the native kidney. In fact, as already noted, the SV40 genome is important in the pathogenesis of focal gomerulosclerosis. Furthermore, reports of polyoma nephropathy in not-yet-transplanted patients could accredit the role of the native kidneys as important viral reservoirs capable of inducing nephropathy in renal transplant patients.