Lauri Kyllönen

University of Tartu, Tartu, Tartumaa, Estonia

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Publications (16)44.01 Total impact

  • Article: BK virus viremia in a well-HLA-matched kidney transplant population mainly on low-dose cyclosporine-based immunosuppression.
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    ABSTRACT: The incidence and clinical course of polyomavirus-associated nephropathy (PyVAN) in our well-HLA-matched kidney transplant population mainly on low-dose cyclosporine-based triple-drug immunosuppression has not been described in detail. We aimed to characterize our patients with PyVAN and BK virus (BKV) viremia. Among 166 kidney transplantations between January 2007 and February 2011 followed up at Helsinki University Hospital nephrology clinic, 136 were screened for BKV viremia by quantitative analysis of BKV DNA in plasma. PyVAN was diagnosed by biopsy histopathology and SV40 T-antigen detection. BKV viremia or PyVAN were treated by reducing immunosuppression. BKV viremia was detected in 12 (9%) patients. PyVAN was diagnosed in six patients (4%). In the six patients with no PyVAN, four had low-level viremia (<10 000 copies/mL) of short duration (<2 months), one had high-level viremia, and one had sustained low-level viremia. After reduction of immunosuppression, all except one patient were able to clear viremia. No grafts were lost due to PyVAN. Even in a low-risk population, BKV viremia and PyVAN occur, highlighting the importance of monitoring viral loads. Reduction of immunosuppression was successful, and no grafts were lost due to PyVAN.
    Clinical Transplantation 10/2012; · 1.67 Impact Factor
  • Article: Donor risk score and baseline biopsy CADI value predict kidney graft outcome.
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    ABSTRACT: Different donor parameters and baseline biopsy have been used to assess the quality of donor organs. There is, however, no consensus which risk factors and chronic changes in the donor kidney can be accepted for transplantation. The study included 481 deceased organ donors and their 829 kidney recipients transplanted during 1995-2005. The biopsies were re-evaluated according to the Banff 97 classification. The prognostic significance of donor risk factors and Chronic Allograft Damage Index (CADI) was analyzed. We propose a new donor risk score, calculated as the count of positive risk factors from a defined set of factors in the medical history of the donor. This donor risk score predicts histological quality of the kidney, graft function, and survival. Transplantations from donors with donor risk score >4 had significantly decreased graft survival compared to those with donor risk scores 0-4; the five-yr death-censored graft survivals were 83% vs. 93%, respectively. High donor CADI score (>3) was associated with worse graft function and survival. Three-yr glomerular filtration rate declined from 82 to 49 mL/min with donor CADI increase from 0 to ≥4. Our results show that high donor risk score and CADI value reflect low functional reserve and risk for poor graft outcome.
    Clinical Transplantation 02/2011; 25(3):E276-83. · 1.67 Impact Factor
  • Article: [Kidney transplantation criteria in Finland].
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    ABSTRACT: In the treatment of end-stage renal disease, kidney transplantation is the best and most cost-effective alternative with regard to both prognosis and quality of life. Problems arise from the disproportion between the number of available allografts and the patients waiting for the transplantation. There are few absolute contraindications to kidney transplantation. In the assessment of the eligibility for transplantation of patients on dialysis the most important factors include cardiovascular diseases, cancer diseases, other diseases affecting operability and life expectancy, age, excess weight and possible infections.
    Duodecim; lääketieteellinen aikakauskirja 01/2010; 126(22):2591-9.
  • Article: Matrix metalloproteinase-26 is present more frequently in squamous cell carcinomas of immunosuppressed compared with immunocompetent patients.
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    ABSTRACT: Skin cancers are the most frequent malignancies in organ transplant recipients (OTRs). Squamous cell carcinomas (SCCs) occur 65-250 times more frequently in OTRs and tend to be aggressive in behavior. Because matrix metalloproteinases (MMPs) have a central role in tumorigenesis and invasion, we investigated the epithelial and stromal MMP and tissue inhibitor of MMP (TIMP) expression profile in SCCs of immunosuppressed (IS) compared with immunocompetent (IC) patients to determine if differences could explain the more aggressive behavior of SCCs in OTRs. Matched pairs from 20 SCCs of IS and IC patients were studied using immunohistochemistry for MMP-1, MMP-7, MMP-8, MMP-9, MMP-13 and MMP-26 and TIMP-1 and TIMP-3. Among all MMPs studied, only staining for MMP-26 was significantly more intense in cancer cells of the post-transplant group compared with the IC group (p = 0.01), whereas MMP-9 expression was more abundant in stromal macrophages surrounding SCCs of IC patients (p = 0.02). MMP-26 expression in cancer cells (p = 0.04) and that of MMP-9 in neutrophils (p = 0.005) were more abundant in SCCs of patients using cyclosporine. We conclude that MMP-26 and MMP-9 may contribute to the more aggressive behavior of SCCs in OTRs.
    Journal of Cutaneous Pathology 10/2009; 36(9):929-36. · 1.56 Impact Factor
  • Article: Incidence of Merkel cell carcinoma in renal transplant recipients.
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    ABSTRACT: The risk factors for Merkel cell carcinoma (MCC), a rare type of skin cancer, are poorly understood. Some evidence suggests that MCC is more common in individuals with abnormal immune function resulting from viral infection, autoimmune disease or organ trans- plantation. The national Renal Transplant Registry and the Finnish Cancer Registry data were searched for recipients of a renal transplant who were diagnosed with MCC. The MCC diagnoses were confirmed using immunohistochemistry. Three cases of MCC were detected among 4200 individuals who underwent renal transplantation from 1967 to 2005 [expected number 0.05, standardized incidence ratio (SIR) 66, 95% CI 14-194, P <0.001]. The latency period between the transplant and detection of MCC ranged from 6 to 19 years. In all three cases, the cause of transplantation was an autoimmune disease. All three died from aggressive MCC with a survival time ranging from 0.5 to 2.1 years. The results indicate that the risk of MCC is greatly increased among subjects who have undergone renal transplantation. The course of the disease appears aggressive in this patient population. The physicians who treat recipients of a kidney transplant should be aware of the substantially increased risk of MCC.
    Nephrology Dialysis Transplantation 08/2009; 24(10):3231-5. · 3.40 Impact Factor
  • Article: MMP-10 (Stromelysin-2) and MMP-21 in human and murine squamous cell cancer.
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    ABSTRACT: The squamous cell cancers (SCC) of renal transplant recipients are more aggressive and metastasize earlier than those of the non-immunocompromised population. Matrix metalloproteinases (MMPs) have a central role in tumor initiation, invasion and metastasis. Our aim was to compare the expression of MMPs-10, -12 and -21 in SCCs from immunosuppressed (IS) and control patients and the contribution of MMPs-10 and -21 to SCC development in the FVB/N-Tg(KRT5-Nfkbia)3Rto mouse line. Immunohistochemical analysis of 25 matched pairs of SCCs, nine of Bowen's disease and timed back skin biopsies of mice with selective inhibition of Rel/NF-kappaB signalling were performed. Semiquantitatively assessed stromal MMP-10 expression was higher (P = 0.009) in the control group when compared with IS patients. Tumor cell-derived MMP-10, -12 and -21 expression did not differ between the groups but stromal fibroblasts of the control SCCs tended to express MMP-21 more abundantly. MMP-10 expression was observed already in Bowen's disease while MMP-21 was absent. MMP-10 and -21 were present in inflammatory or stromal cells in ageing mice while dysplastic keratinocytes and invasive cancer were negative. Our results suggest that MMP-10 may be important in the initial stages of SCC progression and induced in the stroma relating to the general host-response reaction to skin cancer. MMP-21 does not associate with invasion of SCC but may be involved in keratinocyte differentiation.
    Experimental Dermatology 08/2009; 18(12):1044-52. · 3.54 Impact Factor
  • Article: MMP‐10 (Stromelysin‐2) and MMP‐21 in human and murine squamous cell cancer
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    ABSTRACT:   The squamous cell cancers (SCC) of renal transplant recipients are more aggressive and metastasize earlier than those of the non-immunocompromised population. Matrix metalloproteinases (MMPs) have a central role in tumor initiation, invasion and metastasis. Our aim was to compare the expression of MMPs-10, -12 and -21 in SCCs from immunosuppressed (IS) and control patients and the contribution of MMPs-10 and -21 to SCC development in the FVB/N-Tg(KRT5-Nfkbia)3Rto mouse line. Immunohistochemical analysis of 25 matched pairs of SCCs, nine of Bowen’s disease and timed back skin biopsies of mice with selective inhibition of Rel/NF-κB signalling were performed. Semiquantitatively assessed stromal MMP-10 expression was higher (P = 0.009) in the control group when compared with IS patients. Tumor cell-derived MMP-10, -12 and -21 expression did not differ between the groups but stromal fibroblasts of the control SCCs tended to express MMP-21 more abundantly. MMP-10 expression was observed already in Bowen’s disease while MMP-21 was absent. MMP-10 and -21 were present in inflammatory or stromal cells in ageing mice while dysplastic keratinocytes and invasive cancer were negative. Our results suggest that MMP-10 may be important in the initial stages of SCC progression and induced in the stroma relating to the general host-response reaction to skin cancer. MMP-21 does not associate with invasion of SCC but may be involved in keratinocyte differentiation.
    Experimental Dermatology 07/2009; 18(12):1044 - 1052. · 3.54 Impact Factor
  • Article: Differential expression of stromal MMP-1, MMP-9 and TIMP-1 in basal cell carcinomas of immunosuppressed patients and controls.
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    ABSTRACT: Matrix metalloproteinases (MMPs) have an important role in the initiation, growth, and invasion of malignant tumors. Basal cell cancer (BCC) is the most common human malignancy. The risk of BCC is 10-16 times higher among organ transplant recipients compared with the nontransplanted population. The aim of this study was to compare the expression of several MMPs and their tissue inhibitors (TIMPs) in BCCs from kidney transplant recipients and controls. Expression of MMPs-1, -7, -8, -9, -10, -13, -26, and TIMPs-1 and -3 was evaluated by immunohistochemistry in 25 samples of BCC of kidney transplant recipients and 25 matched controls representing superficial and nodular subtypes. No significant differences were detected in MMP expression of BCC tumor cells between immunocompetent and immunodeficient patients. However, MMPs-1 and -9 and TIMP-1 were expressed more frequently in stromal macrophages in the BCCs of immunocompetent patients. When tumor subtypes were compared irrespective of the patient group, more MMP-1-positive fibroblasts and MMP-9-positive neutrophils were detected in the superficial subtype, while stromal MMP-10 expression was more abundant in nodular tumors. Our results suggest that abundant peritumoral expression of TIMP-1 in non-immunocompromised patients limits ECM degradation permissive for cancer cell migration.
    Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 02/2008; 452(1):83-90. · 2.49 Impact Factor
  • Article: Current challenges in renal transplantation from deceased donors.
    Kaija Salmela, Lauri Kyllönen
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    ABSTRACT: The results of 3,165 kidney transplants from deceased donors during the 3 time periods, 1986-92 (n=882), 1993-99 (n=1,107) and 2000-06 (n=1,176) were analysed and following conclusions could be made: 1. One-year patient survival improved from 93.2% to 98.1%, one-year graft survival improved from 86.1% to 95.1% and one-year death censored graft survival improved from 90.4% to 96.6%. Patient death due to cardiovascular disease decreased significantly. Despite that, patient death with a functioning graft became the main cause of graft loss after the first posttransplant year in our most recent cohort. The estimated graft half-life has improved from 9.3 to 20.4 years. 2. The rejection incidence decreased from 28.1% to 14.1%. 3. The mean donor age increased from 35.5 to 47.8 years. The proportion of donors fulfilling the UNOS criteria for extended criteria donors increased from 2.9% to 26.3%. The long-term effects of donor factors on these transplants need to be critically evaluated. 4. A good HLA match remains a sound basis for kidney allocation. Provisions should be made for highly immunized patients and those with unusually long waiting times.
    Clinical transplants 01/2007;
  • Article: Persistent cytomegalovirus infection in kidney allografts is associated with inferior graft function and survival.
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    ABSTRACT: The long-term effects of cytomegalovirus (CMV) infections on kidney allografts are unknown. We examined the impact of persistent intragraft CMV infection on long-term kidney allograft function and survival. CMV was diagnosed in 82/172 renal transplant recipients by antigenemia test and viral cultures. Biopsies from 48 of 82 patients taken after CMV infection and from 15 patients with no previous CMV infection detected were available for the immunohistochemical demonstration of CMV antigens and DNA hybridization in situ. Five-year follow-up data from these 63 patients were analysed. In 17 patients, CMV antigens and/or DNA persisted in the biopsy >2 months after the last positive finding in blood or urine. Patients with persistent intragraft CMV had reduced graft survival (P = 0.041) and Cox regression analysis showed persistent CMV as a risk factor for reduced graft survival (RR: 3.5). Recipients with persistent intragraft CMV had reduced creatinine clearance 1 and 2 years after transplantation (P = 0.007) and in multivariate logistic regression analyses including several potential pre- and posttransplant risk factors, persistent CMV was an independent risk factor for lower clearance at 1 and 2 years (OR: 4.4 and 4.9). Our novel findings show that persistent intragraft CMV infection was associated with reduced kidney allograft function and survival.
    Transplant International 12/2006; 19(11):893-900. · 2.92 Impact Factor
  • Article: Transformation-specific matrix metalloproteinases, MMP-7 and MMP-13, are present in epithelial cells of keratoacanthomas.
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    ABSTRACT: Keratoacanthomas are rapidly growing hyperproliferative skin tumors that may clinically or histologically be difficult to distinguish from well-differentiated squamous cell cancers (SCCs). UV light, trauma, and immune suppression represent their etiological factors. As matrix metalloproteinases (MMPs) are implicated at all stages of tumorigenesis, we investigated the expression profile of several cancer-related MMPs to find markers that would differentiate keratoacanthomas from SCCs and shed light to the pathobiology of keratoacanthoma. Samples from 31 keratoacanthomas and 15 grade I SCCs were studied using immunohistochemistry for MMP-2, -7, -8, -9, -10, -13, and -19 and p16 and laminin-5gamma2 chain. In situ hybridization for MMP-7, -10, and -13 was performed in a subset of tumors. Keratinocytes with atypia, presence of neovascularization, and composition of the inflammatory infiltrate were graded from hematoxylin-eosin stainings. MMP-7 was present in the epithelium of 4/31 keratoacanthomas and 9/15 SCCs, MMP-8 in 3/30 keratoacanthomas and 0/15 SCCs, but MMP-13 in 16/31 keratoacanthomas and 10/15 SCCs, and MMP-10 in 28/31 keratoacanthomas and all cancers. MMP-9 was detected in the epithelium in 5/31 keratoacanthomas and 8/15 SCCs, whereas MMP-2 was only present in fibroblasts in both tumors. MMP-19 was upregulated in proliferating epithelium of keratoacanthomas as was p16. Cytoplasmic laminin-5gamma2 was particularly abundant in keratinocytes at the pushing border of MMP-13-positive keratoacanthomas. We conclude that although some MMPs (MMP-10 and -13) are abundantly expressed in keratoacanthomas, the presence of MMP-7 and -9 in their epithelial pushing border is rare and should raise suspicion of SCC. Further, the loss of MMP-19 and p16 could aid in making the differential diagnosis between well-differentiated SCC and keratoacanthoma. Frequent expression of the transformation-specific MMP-13 in keratoacanthomas suggests that they are not benign tumors but incomplete SCCs.
    Modern Pathology 10/2006; 19(9):1203-12. · 4.79 Impact Factor
  • Article: Predictors of renal allograft histologic damage progression.
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    ABSTRACT: The objective of this study was to analyze factors that are involved in the progression of renal allograft damage in the first 6 mo after transplantation. Donor and 6-mo protocol biopsies of 83 patients who received a renal transplant were classified using the Chronic Allograft Damage Index (CADI). Histologic changes were compared and correlated to clinical parameters at transplantation, at 6 mo, and annually over 2 yr. All CADI components increased significantly in the 6-mo posttransplantation period, except chronic vascular changes and the percentage of glomerulosclerosis. Total cholesterol and LDL- cholesterol at the time of biopsy correlated positively with mesangial matrix increase, and HDL cholesterol correlated negatively with vascular intima increase. High BP at biopsy was associated with tubular atrophy. Diastolic BP at biopsy correlated with 6-mo CADI (CADI-6). Patients with diastolic BP > or =85 mmHg at biopsy had a higher difference between CADI score in protocol biopsies and CADI score in donor biopsies (DeltaCADI) and higher creatinine at 1 and 2 yr. CADI in donor biopsies (CADI-0) >1 was more frequently found in older (odds ratio [OR], 1.07; 95% confidence interval [CI], 1.01 to 1.14) and nontraumatic dead donors (OR, 3.89; 95% CI, 1.13 to 13.33). CADI-6 >3 was more frequently found in those with CADI-0 >1 (OR, 3.82; 95% CI, 1.19 to 12.21), older donors (OR, 1.05; 95% CI, 1.01 to 1.10), and number of AB mismatches (OR, 2.36; 95% CI, 1.09 to 5.10). CADI-0, CADI-6, and DeltaCADI correlated significantly with serum creatinine at hospital discharge, at 6 mo, and at 2 yr. DeltaCADI was affected by initial percentage of glomerulosclerosis (OR, 1.10; 95% CI, 1.02 to 1.19) and creatinine at hospital discharge (OR, 1.01; 95% CI, 1.00 to 1.02). Donor-related as well as nonimmunologic factors, such as hypertension and dyslipidemia, are associated with increased risk for renal allograft damage progression.
    Journal of the American Society of Nephrology 04/2005; 16(3):817-24. · 9.66 Impact Factor
  • Article: [Is tissue typing is unnecessary for kidney transplantation?].
    Lauri Kyllönen, Kaija Salmela, Irma Matinlauri
    Duodecim; lääketieteellinen aikakauskirja 02/2005; 121(2):191-3.
  • Article: Severe gastrointestinal complications after 1,515 adult kidney transplantations.
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    ABSTRACT: We studied, retrospectively, the occurrence of severe gastrointestinal (GI) complications after kidney transplantation. After 1,515 consecutive adult kidney transplantations performed on 1,445 patients during 1990-1999 at our centre, 147 (10%) severe post-transplantation GI complications were found. Ten percent of the complications were fatal. The median follow-up time was 6.2 years. The main complications were gastroduodenal ulcers and colon complications. GI malignancy developed in 13 patients (0.9%). The complication rate for the first post-transplantation year was 4.8%. Delayed graft function, high age and polycystic kidney disease were risk factors. Five-year patient survival rate was significantly lower in patients with a first-year complication than in those with later or no GI complications (68% vs 88%). Graft survival with deaths censored was the same in both groups. In conclusion, severe GI complications during the first post-transplantation year remain a high risk factor also for long-term patient survival.
    Transplant International 11/2004; 17(9):505-10. · 2.92 Impact Factor
  • Article: Why do some diabetic patients on the kidney transplant waiting list not receive a transplant?
    Lauri Kyllönen, Kaija Salmela
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    ABSTRACT: The waiting list (WL) history of 405 diabetic patients placed on the kidney transplantation WL for the years 1993-2000 was examined. By 31 December 2000, 295 (73 %) patients had received a transplant. Of the remaining 110 patients 53 (13 %) were still on the WL; 27 of these were temporarily withdrawn, i.e. non-active, 46 others (11 %) had died and 11 (3 %) had been permanently removed. Patient follow-up continued until the end of 2002. Although the mean total time on the WL of the non-transplanted was twice that of the transplanted patients there were no significant differences in the mean active times on the WL. The mean cumulative withdrawal time of the transplanted and those on the active WL was less than 10 % of their total time on the list, but for the patients who had died or were withdrawn on 31 December 2000 it exceeded 50 %, usually because of diabetic complications. The 5-year survival of the transplanted patients was greatly superior to that of the non-transplanted, as expected. However, the better survival of the transplanted patients is not necessarily proof of a better treatment modality but rather a consequence of the exclusion from transplantation of patients suffering from diabetic complications. It is not justified to compare the survival of transplantable and non-transplantable WL patients.
    Transplant International 11/2004; 17(9):511-7. · 2.92 Impact Factor
  • Article: Ascorbic acid against reperfusion injury in human renal transplantation.
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    ABSTRACT: The cadaveric renal graft is exposed to ischaemic injury during preservation and to oxidative damage during reperfusion. Both these mechanisms are known to cause cell damage, which may impair graft function. Reperfusion injury (RPI) is mediated by reactive oxygen species (ROS). Ascorbic acid (AA) is a potent physiological extracellular scavenger of ROS. We perfused 31 renal grafts immediately before implantation with a solution of Euro-Collins containing 0.5 mg/ml of AA to diminish RPI. From every donor, the contralateral kidney served as a control. The control grafts were perfused with the same perfusion as those of the AA group, only without the AA substitution. We assessed the effect of AA by recording serum creatinine, creatinine clearance, initial graft function and early rejections. The incidence of delayed graft function (DGF) was 32% in the AA group, and 29% in the control group. Other parameters were also similar in both groups, except for the length of DGF, which showed a trend towards a shorter duration in the AA group. The pre-operative systemic AA concentration was significantly ( P=0.01) lower in the haemodialysis patients than in those on peritoneal dialysis. In conclusion, this clinical study could not demonstrate significant benefits of AA in renal transplantation.
    Transplant International 09/2003; 16(8):480-5. · 2.92 Impact Factor