O Koskimies

Oulu University Hospital, Uleoborg, Oulu, Finland

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Publications (72)322.11 Total impact

  • [show abstract] [hide abstract]
    ABSTRACT: Corticosteroids have been shown not to prevent the development of Henoch-Schönlein nephritis. However, long-term follow-up data are scarce. The long-term outcome of patients in a randomized placebo-controlled prednisone study was evaluated 8 years later with a health questionnaire completed by 160/171 (94%) patients and by urine and blood pressure screening (138/171, 81%). Twelve patients had hematuria and/or proteinuria and seven had hypertension. The patients with nephritis at onset of Henoch-Schönlein purpura (HSP) had an increased risk of hypertension and/or urine abnormalities (odds ratio 3.6, p = 0.022, 95% confidence interval 1.3-10.0). There were no differences between the prednisone and placebo groups. Recurrences of purpura were reported by 15 patients, with some recurrences continuing for 10 years. All five reported pregnancies were complicated by proteinuria. Four patients presented with hematuria and/or proteinuria at the control visit, and four had hypertension. Of these, two had a decreased estimated glomerular filtration rate. HSP has a good long-term prognosis in unselected patients, although skin relapses with/without late-onset nephritis may occur, even a decade after the initial disease. Urine and blood pressure abnormalities 8 years after HSP are associated with nephritis at its onset. Early prednisone treatment does not affect the outcome and should not be routinely used.
    Pediatric Nephrology 02/2012; 27(6):933-9. · 2.94 Impact Factor
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    Pediatric Nephrology 08/2011; · 2.94 Impact Factor
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    ABSTRACT: Knowledge about how to treat severe Henoch-Schönlein nephritis (HSN) is scarce. The aim of our study is to compare cyclosporine A (CyA) and methylprednisolone pulses (MP) in the treatment of severe HSN. Out of 24 pediatric HSN patients with nephrotic-range proteinuria or crescentic HSN in kidney biopsy, seven were randomized to receive CyA for 12 months at an initial dose of 5 mg/kg and eight to receive 3 MP pulses of 30 mg/kg followed by prednisone for 4 months. The other nine patients received identical treatment without randomization. Kidney biopsies were performed at inclusion and after 2 years. The primary outcomes were the duration of proteinuria and hematuria, estimated glomerular filtration rate, and renal biopsy histology. All the 11 CyA-treated patients achieved resolution of nephrotic-range proteinuria within 3 months, while the MP-group response was slower, and in 6/13 was not achieved with the initial treatment. Additional immunosuppressive treatment was needed in none of the CyA-treated patients but in six patients treated with MP (difference in proportion 46%, p = 0.008). The 2-year control biopsies were similarly improved in both groups. After mean 6.1 years (2.2-10.4 years), 16 patients (eight CyA, eight MP) had no renal symptoms and six (three CyA, three MP) had persistent nephropathy but normal renal function. One MP-treated patient had reduced renal function and another had developed ESRD and received a renal transplant. CyA gave a 100% resolution of nephrotic-range proteinuria and a 100% renal survival rate without additional therapy after a mean follow-up of 6 years. Treatment of HSN with CyA is efficacious, safe and not inferior to MP.
    Pediatric Nephrology 05/2011; 26(12):2159-66. · 2.94 Impact Factor
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    ABSTRACT: To assess the risk factors for developing Henoch-Schönlein purpura nephritis (HSN) and to determine the time period when renal involvement is unlikely after the initial disease onset. A prospective study of 223 paediatric patients to examine renal manifestations of Henoch-Schönlein purpura (HSP). The patient's condition was monitored with five outpatient visits to the research centre and urine dipstick testing at home. HSN occurred in 102/223 (46%) patients, consisting of isolated haematuria in 14%, isolated proteinuria in 9%, both haematuria and proteinuria in 56%, nephrotic-range proteinuria in 20% and nephrotic-nephritic syndrome in 1%. The patients who developed HSN were significantly older than those who did not (8.2±3.8 vs 6.2±3.0 years, p<0.001, CI for the difference 1.1 to 2.9). Nephritis occurred a mean of 14 days after HSP diagnosis, and within 1 month in the majority of cases. The risk of developing HSN after 2 months was 2%. Prednisone prophylaxis did not affect the timing of the appearance of nephritis. The risk factors for developing nephritis were age over 8 years at onset (OR 2.7, p=0.002, CI 1.4 to 5.1), abdominal pain (OR 2.1, p=0.017, CI 1.1 to 3.7) and recurrence of HSP disease (OR 3.1, p=0.002, CI 1.5 to 6.3). Patients with two or three risk factors developed nephritis in 63% and 87% of cases, respectively. Laboratory tests or blood pressure measurement at onset did not predict the occurrence of nephritis. The authors recommend weekly home urine dipstick analyses for the first 2 months for patients with HSP. Patients with nephritis should be followed up for more than 6 months as well as the patients with HSP recurrence.
    Archives of Disease in Childhood 11/2010; 95(11):877-82. · 3.05 Impact Factor
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    ABSTRACT: To describe the extrarenal symptoms and clinical course of Henoch-Schönlein purpura (HSP). A prospective national multicentre trial with 6-month follow-up. Patients A total of 223 newly diagnosed paediatric HSP patients. Purpura was the initial symptom in 73% of the patients and was preceded by joint or gastrointestinal manifestations in the rest by a mean of 4 days. Joint symptoms, abdominal pain, melena, nephritis and recurrences occurred in 90%, 57%, 8%, 46% and 25% of the patients, respectively. Orchitis affected 17/122 (14%) of the boys. Seven patients developed protein-losing enteropathy characterised by abdominal pain, oedema and serum albumin under 30 g/l, and an additional 49 patients had subnormal albumin levels without any proteinuria. Positive fecal occult blood (26/117, 22%) and α1-antitrypsin (7/77, 9%) suggested mucosal injury even in the patients without gastrointestinal symptoms. HSP was often preceded by various bacterial, especially streptococcal (36%) and viral infections. Previous streptococcal infection did not induce changes in the level of complement component C3. Recurrences were more frequent in patients >8 years of age (OR 3.7, CI 2.0 to 7.0, p<0.001) and in patients with nephritis (OR 4.6, CI 2.3 to 8.9, p<0.001). Patients with severe HSP nephritis had more extrarenal symptoms up to 6 months. There was no difference in the clinical course between the prednisone-treated and non-treated patients during the 6-month follow-up. Serum albumin is often low in HSP patients without proteinuria, due to protein loss via the intestine. Although corticosteroids alleviate the symptoms, they seem not to alter the clinical course of HSP during 6 months of follow-up.
    Archives of Disease in Childhood 04/2010; 95(11):871-6. · 3.05 Impact Factor
  • Duodecim; lääketieteellinen aikakauskirja 02/2007; 123(11):1329-37.
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    ABSTRACT: We evaluated the natural long-term outcome after childhood IgA nephritis. Altogether 55 patients with biopsy-proven IgA nephritis were identified, 37 (67%) responded to the health questionnaire and 31 (56%) participated in the medical examination after a mean follow-up of 18.7 years (SD 6.2; range 8.5-29.8). The results of medical examination, onset data and the re-analysis of original biopsies of 31 participants were used when analyzing the predictive factors for persistent nephropathy, i.e. constant proteinuria/hematuria or end-stage renal disease (ESRD). All patients' medical history data were obtained from regional hospitals and renal survival data from the national kidney register. Six (11%) of the 55 identified patients had developed ESRD. Sixteen (52%) of the 31 participants were not attending for regular follow-up visits after the acute phase. Twenty-two (71%) had renal symptoms and 12 (39%) were receiving drugs for hypertension/proteinuria at their latest follow-up visit. The chronicity index and total biopsy score in the first renal biopsy were higher in patients with persistent nephropathy or ESRD than in those without (p=0.022 and p=0.014, respectively). Nine (69%) of the 13 subjects who had been over 16 years of age at diagnosis had persistent nephropathy or ESRD, compared with 4 (22%) of the 18 subjects who had been under 16 years of age (relative risk 3.1, 95% CI 1.2-8.0). Pregnancy complications were common: 12 (55%) of the 22 pregnancies had been complicated by proteinuria and/or hypertension, and the prematurity rate was 30%. Long-term follow-up during adulthood is needed even after mild childhood IgA nephritis, especially in women during and after pregnancy.
    Pediatric Nephrology 10/2006; 21(9):1266-73. · 2.94 Impact Factor
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    ABSTRACT: To evaluate the efficacy of early prednisone therapy in preventing renal and treating extrarenal and renal symptoms in Henoch-Schönlein purpura (HSP) in a placebo-controlled trial. A total of 171 patients (84 treated with prednisone and 87 receiving placebo) were included and followed up for 6 months. The endpoints were renal involvement at 1, 3, and 6 months and healing of extrarenal symptoms. The analyses were performed on an intent-to-treat basis. Prednisone (1 mg/kg/day for 2 weeks, with weaning over the subsequent 2 weeks) was effective in reducing the intensity of abdominal pain (pain score, 2.5 vs 4.8; P = .029) and joint pain (4.6 vs 7.3; P = .030). Prednisone did not prevent the development of renal symptoms but was effective in treating them; renal symptoms resolved in 61% of the prednisone patients after treatment, compared with 34% of the placebo patients (difference = 27%; 95% confidence interval = 3% to 47%; P = .024). The general use of prednisone in HSP is not supported, but patients with disturbing symptoms may benefit from early treatment, because prednisone reduces extrarenal symptoms and is effective in altering (but not preventing) the course of renal involvement.
    Journal of Pediatrics 09/2006; 149(2):241-7. · 4.04 Impact Factor
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    ABSTRACT: The pathogenesis of minimal change nephrotic syndrome (MCNS) is still unknown. We performed a clinical and genetic evaluation of 104 adults (mean age 35 years) who presented with MCNS in childhood (mean follow-up 30 years). Clinical data and the present health status were evaluated. Also, the genes encoding the four major slit diaphragm proteins, nephrin, podocin, Neph1 and CD2-associated protein were sequenced in 38 patients with MCNS of varying severity. MCNS presented at the mean age of 5 years, and 80% of the patients relapsed 1-28 (median 3) times during childhood. The 14 subjects (14%) who had proteinuric episodes still in adulthood had a refractory disease already as children. The participants did not show a strong tendency for allergy or immune diseases, and no familial clustering of MCNS was observed. The genetic analyses revealed heterozygous amino acid changes in nephrin and podocin in 10 of the 38 patients studied. On the other hand, the genes coding for Neph1 and CD2AP were highly conserved and no amino acid substitutions were detected. In conclusion, MCNS is a multifactorial disease, in which genetics play a minor role. Allelic variants of the podocyte proteins may, however, modify the phenotype in occasional individuals.
    Pediatric Nephrology 09/2005; 20(8):1073-80. · 2.94 Impact Factor
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    ABSTRACT: Glomerular epithelial cells (podocytes) play an important role in the pathogenesis of proteinuria. Podocyte foot process effacement is characteristic for proteinuric kidneys, and genetic defects in podocyte slit diaphragm proteins may cause nephrotic syndrome. In this work, a systematic electron microscopic analysis was performed of the structural changes of podocytes in two important nephrotic kidney diseases, congenital nephrotic syndrome of the Finnish type and minimal-change nephrotic syndrome (MCNS). The results showed that (1) podocyte foot process effacement was present not only in proteinuric glomeruli but also in nonproteinuric MCNS kidneys; (2) podocytes in proteinuric glomeruli did not show detachment from the basement membrane or cell membrane ruptures; (3) the number of pinocytic membrane invaginations in the basal and apical parts of the podocytes was comparable in proteinuric and control kidneys; (4) in proteinuric kidneys, the podocyte slit pore density was decreased by 69 to 80% and up to half of the slits were so "tight" that no visible space between foot processes was seen; thus, the filtration surface area between podocytes was dramatically reduced; and (5) in the narrow MCNS slit pores, nephrin was located in the apical part of the podocyte foot process, indicating vertical transfer of the slit diaphragm complex in proteinuria. In conclusion, these results suggest that protein leakage in the two nephrotic syndromes studied occurs through defective podocyte slits, and the other structural alterations commonly seen in electron microscopy are secondary to, not a prerequisite for, the development of proteinuria.
    Journal of the American Society of Nephrology 11/2004; 15(10):2611-8. · 8.99 Impact Factor
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    ABSTRACT: Minimal change nephrotic syndrome (MCNS) is a major problem in pediatric nephrology. While the pathogenesis of MCNS is not known, the latest discoveries in the genetic diseases indicate that glomerular epithelial cells (podocytes) and the slit diaphragm play a primary role in development of proteinuria. Because nephrin is known to be a major component of the slit diaphragm, we analyzed the structure of nephrin gene (NPHS1) in patients with MCNS of different severity. Clinical data and DNA samples were collected from 25 adults who had biopsy-proven MCNS in childhood. A direct sequencing was performed to all 29 exons of the NPHS1 gene. The significance of the findings was evaluated by similar analysis of DNA samples from 25 healthy control patients. The analysis of NPHS1 revealed no specific MCNS-associated mutation. However, 5 of the 25 MCNS patients had heterozygous allelic variants leading to nonconservative amino acid substitutions not previously reported (G879R; R800C; T294I; A916S). One of the five patients also had the Fin-major mutation, and two had new, conservative amino acid substitutions (S786N; A342G). Three of the five patients were classified as steroid sensitive, one was an early nonresponder, and one patient showed clear resistance to steroid treatment. Six known polymorphic changes in NPHS1 were also found, three of them leading to amino acid changes. The number of allelic variants was high both in MCNS patients and control patients (mean 3.0 and 2.6). The results suggest that genetic changes in nephrin may have a pathogenetic role in some patients with MCNS.
    Kidney International 06/2004; 65(5):1856-63. · 7.92 Impact Factor
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    ABSTRACT: All children with Henoch-Schoenlein glomerulonephritis (HSP-GN) and nephrotic-range proteinuria (> 40 mg/h/m2), treated at 5 university hospitals and in 1 central hospital in Finland during in 1990-1997, were analyzed retrospectively. The mean age of these 19 patients (8 girls, 11 boys) at the time of diagnosis was 9.9 years (range 4.6-15.1 years). A renal biopsy had been performed in all cases, giving findings according to the classification used in the International Study of Kidney Diseases in Children (ISKDC) of grade II (4 patients), grade III (10), grade IV (4) and grade V (1). Six patients underwent a second biopsy. The yearly incidence of nephrotic-range HSP-GN in Finland was 2 per 1 million children under 15 years of age. After a mean follow-up of 4.6 years (range 9 months-9.1 years), 3 patients (15.7%) had no signs of nephritis, 11 (57.9%) had proteinuria < 1 g/day or microscopic hematuria, 2 (10.5%) had proteinuria > 1 g/day, and 3 (15.7%) had developed ESRD or uremia. 47% of the patients needed medication for proteinuria at the time of the latest follow-up. The first kidney biopsy did not predict the outcome of HSP-GN, since all the patients with the poorest outcome had only ISKDC II-III findings in their first biopsy. According to our series, the morbidity in cases of HSP-GN with nephrotic-range proteinuria is high and a close clinical follow-up is needed. The treatment of HSP-GN patients should be based on the clinical presentation rather than on the biopsy findings.
    Clinical nephrology 08/2003; 60(2):80-4. · 1.29 Impact Factor
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    ABSTRACT: The pathophysiology of proteinuria in acquired kidney diseases is mostly unknown. Recent findings in genetic renal diseases suggest that glomerular epithelial cells (podocytes) and the slit diaphragm connecting the podocyte foot processes play an important role in the development of proteinuria. In this work we systematically evaluated the podocyte slit pores by transmission electron microscopy in two important nephrotic diseases, minimal change nephrotic syndrome (MCNS) and membranous nephropathy (MN). As controls, we used kidneys with tubulointerstitial nephritis (TIN). Effacement of podocyte foot processes was evident in proteinuric kidneys. However, quite normal looking foot processes and slit pores with varying width were also observed. Careful analysis of slit pores revealed, that the proportion of the pores spanned by the linear image of slit diaphragm, was reduced by 39% in kidneys from MCNS patients (1265 pores analyzed) compared with TIN samples (902 pores analyzed, p = 0.0003). To enhance the detection rate of the slit diaphragms, the "empty" podocyte pores were further analyzed with tilting series from -45 to +45. This revealed the linear diaphragm image in 71% and 26% of the slits in TIN and MCNS kidneys, respectively (p = 0.0003). In contrast to findings in MCNS, no significant reduction of the slit diaphragms were seen in MN kidneys compared with the controls. The results suggest that MCNS is associated with disruption of glomerular slit diaphragms.
    Pediatric Research 10/2002; 52(3):349-55. · 2.67 Impact Factor
  • Jaana Ronkainen, Matti Nuutinen, Olli Koskimies
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    ABSTRACT: Henoch-Schönlein purpura arising in childhood could cause renal impairment or even an end-stage renal disease later in life. We aimed to assess long-term outcome of childhood Henoch-Schönlein purpura after 24 years. We studied a cohort of 26 boys and 26 girls who were treated for Henoch-Schönlein purpura at Helsinki University Hospital during 1964-83. Mean follow-up was 24.1 years (SD 6.0; 16.4-36.5). All participants were asked about their state of health in a questionnaire, and 47 (90%) were examined by a doctor. Patients' medical history data were obtained from health-care centres and regional hospitals. Seven (35%) of 20 adults who had severe Henoch-Schönlein purpura and glomerulonephritis at onset had renal impairment as adults, compared with two (7%) of 27 with mild or no renal symptoms at onset (relative risk 4.7, 95% CI 1.3-18.7). Relative risk for a poor outcome was 5.0 in women (1.1-32.5) and 2.0 in men (0.2-17.5). All patients with no renal symptoms at onset had a good outcome after 24 years of follow-up. Severity of first kidney biopsy finding did not correlate with risk of a poor outcome. 16 (70%) of 23 pregnancies had been complicated by hypertension, proteinuria, or both. Five (56%) of the nine women with complicated pregnancies had a poor renal outcome. Long-term follow-up of all patients who had Henoch-Schönlein purpura with severe renal symptoms at onset is needed during adulthood. All women who had even mild renal symptoms at onset of Henoch-Schönlein purpura should be carefully observed during and after pregnancy.
    The Lancet 09/2002; 360(9334):666-70. · 39.06 Impact Factor
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    ABSTRACT: Major urinary tract abnormalities are detected in 20 to 40% of infants with acute pyelonephritis (APN). Early detection of structural defects is essential for protecting the kidneys from reinfection and subsequent scarring. The purpose of this study was to investigate whether any factors present during the acute phase of infection could predict the presence of existing significant urinary tract abnormalities in infants. A prospective study of 180 infants, aged 1 to 24 months, with APN was conducted. Blood and urine samples were collected. Renal ultrasound (US) was performed within 0 to 6 days from admission. Final diagnosis of the urinary tract anatomy was elucidated using the results of two or more radiologic imaging studies. Risk factors for the presence of significant urinary tract abnormalities in infants were pathogens other than Escherichia coli in urine [relative risk (RR) 3.4, 95% confidence interval (CI) 2.2 to 5.3; P = 0.001], positive blood culture (RR 2.3, 95% CI 1.3 to 4.0; P = 0.039), young age (1 to 6 months) (RR 2.2, 95% CI 1.3 to 3.9; P = 0.004), lack of papG adhesin genes of E. coli in urine (RR 2.1, 95% CI 1.2 to 3.9; P = 0.016) and abnormal renal US (RR 2.0, 95% CI 1.2 to 3.4; P = 0.008). Infants 1 to 6 months of age with APN caused by bacteria other than E. coli or by papG-negative E. coli strain, positive blood culture and abnormal renal US carry an increased risk for significant urinary tract abnormalities and need enforced follow-up.
    The Pediatric Infectious Disease Journal 07/2001; 20(6):597-601. · 3.57 Impact Factor
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    ABSTRACT: Nephronophthisis (NPH) is a chronic tubulointerstitial nephritis leading to terminal renal insufficiency. The disease is heterogeneous, but usually the inheritance pattern is autosomal recessive. In 80% of cases, the disease is caused by a homozygous deletion in NPHP1 gene in chromosome 2q13. Ulcerative colitis is an inflammatory bowel disease with chronic diarrhea, rectal bleeding and characteristic histological findings. Its etiology is suggested to be multifactorial, consisting of genetic susceptibility and unknown exogenous factors. We present two siblings with NPH and ulcerative colitis. As NPH in this family is not linked to 2q13, this association may represent a new, syndromic form of NPH.
    Pediatric Nephrology 07/2001; 16(6):507-9. · 2.94 Impact Factor
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    ABSTRACT: Alport syndrome (AS) is a hereditary kidney disorder, mainly caused by mutations in the X-chromosomal gene (COL4A5) encoding the type IV collagen a5 chain. In this study, detection of COL4A5 mutations was performed in 17 Finnish Alport syndrome families. Regions around the 51 previously known exons, as well as the two recently characterized exons 41A and 41B in COL4A5, were PCR-amplified from the patient DNA. Direct sequencing of the amplified products was performed and mutations were found in 12 families. None of the mutations involved exons 41A or 41B. Three of the mutations were potential splicing mutations, two of which were studied at the mRNA level. Seven of the mutations were single base substitutions, and two were deletions. In five families, no mutations were found.
    Human Mutation 07/2000; 15(6):579. · 5.21 Impact Factor
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    ABSTRACT: P-fimbrial genotypes of Escherichia coli strains and their possible association with urinary tract abnormalities were studied in infants with pyelonephritis. A total of 153 urinary E. coli strains were analyzed by polymerase chain reaction for class I, II, and III alleles of the pyelonephritis-associated adhesin gene papG. Strains with any class II papG alleles were found significantly more often in infants with normal anatomy and function or in infants with clinically insignificant abnormalities than they were in infants with significant abnormalities (90 of 119 vs. 14 of 34 infants; P<. 001). On the other hand, strains without any papG alleles were found significantly more often in infants with major urinary tract abnormalities (11 of 34 vs. 17 of 119 infants; P=.016). Our genotypic findings indicate that, especially in infants with a normal urinary tract, infection is caused by more-virulent E. coli than is present in infants without a normal urinary tract. This virulence could be due to expression of pyelonephritogenic P fimbriae by an infecting E. coli strain.
    The Journal of Infectious Diseases 05/2000; 181(5):1822-4. · 5.85 Impact Factor
  • J Ronkainen, M Nuutinen, O Koskimies
    Duodecim; lääketieteellinen aikakauskirja 02/2000; 116(21):2339-46; quiz 2346, 2389.
  • Human Mutation - HUM MUTAT. 01/2000; 15(6).

Publication Stats

1k Citations
322.11 Total Impact Points

Institutions

  • 2002–2012
    • Oulu University Hospital
      Uleoborg, Oulu, Finland
  • 1973–2012
    • University of Helsinki
      • • The Hospital for Children and Adolescents
      • • Hospital for Children and Adolescents and Biomedicum Helsinki
      • • Department of Medical Genetics
      Helsinki, Southern Finland Province, Finland
  • 1988–1998
    • Helsinki University Central Hospital
      • • Division of Nephrology
      • • Children's Hospital
      Helsinki, Province of Southern Finland, Finland
  • 1997
    • Central Hospital Central Finland
      Jyväskylä, Province of Western Finland, Finland