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1.
J Infect Dis ; 228(6): 742-750, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37225667

RESUMO

BACKGROUND: Bone mineral density (BMD) loss may be accelerated in people with HIV (PLWH). It is unknown whether a polygenic risk score (PRS) is associated with low BMD in PLWH. METHODS: Swiss HIV Cohort Study participants of self-reported European descent underwent ≥2 per-protocol dual x-ray absorptiometry (DXA) measurements ≥2 years apart (2011-2020). Univariable and multivariable odds ratios (ORs) for DXA-defined osteoporosis were based on traditional and HIV-related risk factors and a genome-wide PRS built from 9413 single-nucleotide polymorphisms associated with low BMD in the general population. Controls were free from osteoporosis/osteopenia on all DXA measurements. RESULTS: We included 438 participants: 149 with osteoporosis and 289 controls (median age, 53 years; 82% male, 95% with suppressed HIV RNA). Participants with unfavorable osteoporosis PRS (top vs bottom quintile) had univariable and multivariable-adjusted osteoporosis ORs of 4.76 (95% CI, 2.34-9.67) and 4.13 (1.86-9.18), respectively. For comparison, hepatitis C seropositivity, 5-year tenofovir disoproxil fumarate exposure, and parent history of hip fracture yielded univariable osteoporosis ORs of 2.26 (1.37-3.74), 1.84 (1.40-2.43), and 1.54 (0.82-2.9). CONCLUSIONS: In PLWH in Switzerland, osteoporosis was independently associated with a BMD-associated PRS after adjustment for established risk factors, including exposure to tenofovir disoproxil fumarate.


Assuntos
Doenças Ósseas Metabólicas , Infecções por HIV , Osteoporose , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos de Coortes , HIV , Suíça/epidemiologia , Osteoporose/epidemiologia , Osteoporose/genética , Osteoporose/induzido quimicamente , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Fatores de Risco , Densidade Óssea/genética , Doenças Ósseas Metabólicas/induzido quimicamente , Doenças Ósseas Metabólicas/complicações , Doenças Ósseas Metabólicas/epidemiologia , Tenofovir/efeitos adversos
2.
Can J Kidney Health Dis ; 10: 20543581231160004, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37009424

RESUMO

Background: The use of small pediatric donors (age ≤ 5 years and body weight < 20kg) for adult transplant recipients is still regarded controversially in terms of early complications, long-term outcomes, and development of hyperfiltration injury due to body size mismatch. Objective: To investigate long-term outcomes of adult renal allograft recipients receiving a kidney from small pediatric donor (SPD) in terms of kidney function and early features of hyperfiltration injury such as histological changes and proteinuria. Design: Retrospective, single center study. Settings: Transplant center of the University Hospital of Basel, Switzerland. Patients: Adult renal allograft recipients receiving a kidney from a small pediatric donor at our center between 2005 and 2017. Methods: The outcome of 47 transplants from SPD were compared with 153 kidney transplants from deceased-standard criteria donors (SCD) occurring during the same time period. Incidence of clinical signs of hyperfiltration injury (eg, proteinuria) was investigated. According to our policy, surveillance biopsies were taken at 3 and 6 months post-transplant and were evaluated in terms of signs of hyperfiltration injury. Results: At a median follow-up of 2.3 years post-transplant, death-censored graft survival of SPD was comparable to transplants from SCD (94% vs 93%; P = .54). Furthermore, allograft function at last follow-up (estimated glomerular filtration rate-Modification of Diet in Renal Disease) was significantly higher in pediatric transplant (80 vs 55 ml/min/1.73 m2, P = .002). We found histological signs of early hyperfiltration injury in 55% of SPD. There was an equally low proteinuria in both groups during follow-up. Limitations: It is a single center and retrospective observational study with small sample size. The outcomes were investigated in a well-selected population of recipients with low body mass index, low immunological risk, and well-controlled hypertension and was not compared with equal selected group of recipients. Conclusions: Early histological and clinical signs of hyperfiltration injury in SPD is frequent. Despite the hyperfiltration injury, there is an equal allograft survival and even superior allograft function in SPD compared with SCD during follow-up. This observation supports the concept of high adaptive capacity of pediatric donor kidneys.


Contexte: Le recours à de très jeunes donneurs pédiatriques (âge: ≤ 5 ans; poids < 20 kg), pour des greffes chez des receveurs adultes, suscite encore des préoccupations quant aux complications précoces, aux résultats à long terme et au développement de lésions d'hyperfiltration liées à la disproportion de taille corporelle. Objectif: Examiner les résultats à long terme de patients adultes greffés rénaux ayant reçu l'organe d'un très jeune donneur pédiatrique (TJDP), soit la fonction rénale et les signes précoces de lésions d'hyperfiltration (p. ex. changements histologiques et protéinurie). Type d'étude: Étude rétrospective dans un seul établissement. Cadre: Le centre de transplantation de l'hôpital universitaire de Bâle (Suisse). Sujets: Les adultes ayant reçu une greffe rénale provenant d'un très jeune donneur pédiatrique dans notre centre entre 2005 et 2017. Méthodologie: Les résultats de 47 transplantations impliquant des TJDP ont été comparés à ceux de 153 transplantations rénales survenues au cours de la même période, mais impliquant des donneurs décédés répondant aux critères standard (DDCS). L'incidence des signes cliniques de lésions d'hyperfiltration (p. ex. protéinurie) a été étudiée. Selon notre politique, des biopsies de surveillance ont été réalisées à 3 et 6 mois post-transplantation et évaluées pour les signes d'hyperfiltration. Résultats: Lors d'un suivi médian de 2,3 ans post-transplantation, le pourcentage de survie du greffon (censurée pour les décès) provenant de TJDP était comparable à celui de DDCS (94 % c. 93 %; p = 0,54). De plus, la fonction du greffon lors du dernier suivi (DFGe basé sur l'équation MDRD) était significativement plus élevée dans les cas de transplantation pédiatrique (80 ml/min/1,73 m2 contre 55 ml/min/1,73 m2; p=0,002). Des signes histologiques de lésions précoces dues à une hyperfiltration ont été observés dans 55 % des cas impliquant un TJDP. La protéinurie était peu importante et équivalente dans les deux groupes au cours du suivi. Limites: Il s'agit d'une étude observationnelle et rétrospective menée dans un seul centre et sur un faible échantillon. Les résultats ont été obtenus dans une population bien précise de receveurs avec un IMC peu élevé, un risque immunologique faible et une hypertension bien contrôlée; ces résultats n'ont pas été comparés à un autre groupe de receveurs équivalents. Conclusion: Des signes histologiques et cliniques précoces de lésion d'hyperfiltration sont fréquents chez les TJDP. Malgré cela, pendant la période de suivi, la survie de greffon provenant d'un TJDP s'est avérée comparable à celles d'organes provenant de DDCS et la fonction supérieure. Cette observation appuie l'hypothèse d'une grande capacité d'adaptation des reins provenant de donneurs pédiatriques.

3.
J Clin Med ; 9(7)2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32645935

RESUMO

Nocardiosis is primarily an opportunistic infection affecting immunosuppressed individuals, in whom it most commonly presents as pulmonary infection and sometimes cerebral abscesses. Isolated abdominal or retroperitoneal nocardiosis is rare. Here, we report the second case, to our knowledge, of isolated abdominal nocardiosis due to Nocardia paucivorans and provide a comprehensive review of intra-abdominal nocardiosis. The acquisition of abdominal nocardiosis is believed to occur via hematogenous spreading after pulmonary or percutaneous inoculation or possibly via direct abdominal inoculation. Cases of Nocardia peritonitis have been reported in patients on peritoneal dialysis. Accurate diagnosis of abdominal nocardiosis requires histological and/or microbiological examination of appropriate, radiologically or surgically obtained biopsy specimens. Malignancy may initially be suspected when the patient presents with an abdominal mass. Successful therapy usually includes either percutaneous or surgical abscess drainage plus prolonged combination antimicrobial therapy.

4.
Swiss Med Wkly ; 147: w14497, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28871572

RESUMO

BACKGROUND: We evaluated the prospectively collected data about the incidence of early peri- and postoperative complications, and potential risk factors for adverse outcomes after living kidney donation in Switzerland. METHODS: Peri- and postoperative events were prospectively recorded on a questionnaire by the local transplant teams of all Swiss transplant centres and evaluated by the Swiss Organ Living Donor Health Registry. Complications were classified according to the Clavien grading system. A total of 1649 consecutive donors between 1998 and 2015 were included in the analysis. RESULTS: There was no perioperative mortality observed. The overall complication rate was 13.5%. Major complications defined as Clavien ≥3 occurred in 2.1% of donors. Obesity was not associated with any complications. Donor age >70years was associated with major complications (odds ratio [OR] 3.99) and genitourinary complications (urinary tract infection OR 5.85; urinary retention OR 6.61). There were more major complications observed in donors with laparoscopic surgery versus open surgery (p = 0.048), but an equal overall complication rate (p = 0.094). CONCLUSION: We found a low rate of major and minor complications, independent of surgical technique, after living donor nephrectomy. There was no elevated complication rate in obese donors. In contrast, elderly donors >70 years had an elevated risk for perioperative complications.


Assuntos
Transplante de Rim/métodos , Doadores Vivos , Nefrectomia/métodos , Complicações Pós-Operatórias/etiologia , Fatores Etários , Feminino , Humanos , Rim , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Fatores de Risco , Suíça
7.
Urology ; 88: 104-10, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26674748

RESUMO

OBJECTIVE: To evaluate the incidence and risk factors for urothelial cancer (UC) as well as the oncological outcome and allograft function in renal transplant recipients. SUBJECTS/PATIENTS: We conducted a retrospective analysis of 1855 consecutive patients undergoing renal transplantation (TX) between February 1982 and May 2014 at a single center. UC incidence, overall and cancer-specific survival, recurrence and progression rates, risk factors for UC, and renal function were determined. Fisher's exact test and log-rank Mantel-Cox test were used as appropriate. RESULTS: In renal transplant recipients, incidence of de novo UC was 1.35% (25/1855). Deceased donor transplantation (P = .002), increased age at transplantation (P = .011), and analgesic abuse (P = .005) were significant risk factors for the development of UC post-TX. Progression rate and recurrence rate were doubled for post-TX-UC but stable for patients with pre-TX-UC compared with the general population. Analgesic abuse was associated with worse cancer specific and overall survival in post-TX patients. The overall survival status was significantly lower for post-TX patients at a median of 34 months vs 222 months in control patients. Adjuvant treatment was scarcely used. UC had no significant influence on graft function. CONCLUSION: A higher incidence of UC was identified in renal transplant recipients compared with that for the general population. These observations justify screening for UC in renal transplant patients, especially considering that in a large proportion, a tentative diagnosis was possible with noninvasive urine analysis. Prudent adjuvant treatment for UC should be used. Limitations of this study were the retrospective design and the single-center experience.


Assuntos
Transplante de Rim , Complicações Pós-Operatórias/epidemiologia , Neoplasias Urológicas/epidemiologia , Urotélio , Feminino , Humanos , Incidência , Masculino , Estudos Retrospectivos , Fatores de Risco
8.
Swiss Med Wkly ; 145: w14135, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26023828

RESUMO

OBJECTIVES: We aimed to explore acute kidney injury (AKI) Kidney Disease Improving Global Guidelines (KDIGO) stage 2 to 3 in a cohort of antiretroviral treated HIV-infected individuals. METHODS: HIV-infected individuals of the Swiss HIV Cohort Study (Basel site), treated with combination antiretroviral therapy (cART) 2002-2013, were included. AKI was defined and classified according to the KDIGO Clinical Practice Guidelines for AKI. Data were prospectively collected and reports of kidney biopsies obtained from records. RESULTS: Among 1,153 cART-treated patients, 13 experienced AKI KDIGO stage 2 to 3 (1 patient stage 2, 12 patients stage 3; median age 46 years; 9 male; median CD4 count 366 cells/µl), corresponding to an incidence rate of AKI of 0.77 (95% confidence interval 0.45-1.33) per 1000 patient-years. Baseline estimated glomerular filtration rate (eGFR) was 87 ml/min (interquartile range 66-100). Ten patients were treated with tenofovir (TDF). Nine patients (69%) had ≥1 cardiovascular risk factor, only two patients had known pre-existing kidney disease. Three patients needed chronic and two temporary dialysis. AKI was associated with TDF therapy in 6 of 13 (46%) patients (mean TDF exposure time before AKI 41 months). Impaired renal function was partially reversible in all patients. In three patients with biopsy-proven pre-existing kidney disease (AA amyloidosis, calcineurin inhibitor-induced nephropathy and minimal change glomerulopathy), TDF potentially added to AKI. CONCLUSIONS: AKI KDIGO stage 2 to 3 demonstrates complex associations at the individual level and can occur without early signs. Although treatment with TDF and presence of cardiovascular risk factors were found frequently, predicting AKI seems very difficult.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Antirretrovirais/efeitos adversos , Infecções por HIV/tratamento farmacológico , Tenofovir/efeitos adversos , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Arteriosclerose/epidemiologia , Diabetes Mellitus/epidemiologia , Quimioterapia Combinada/efeitos adversos , Feminino , Taxa de Filtração Glomerular , Humanos , Hipertensão/epidemiologia , Incidência , Masculino , Pessoa de Meia-Idade , Diálise Renal , Índice de Gravidade de Doença
9.
Clin Transplant ; 27(3): E302-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23528134

RESUMO

BACKGROUND: Kidneys from pediatric donors weighing <10 kg are preferably transplanted en bloc, while kidneys from donors weighing >15 kg can be safely transplanted as single kidneys. However, single kidney transplantation from donors weighing 10-14 kg is controversial and has not been well investigated. METHODS: We analyzed the outcome of 15 recipients of single kidneys from donors weighing 10-14 kg (study group) with 40 recipients receiving an allograft from ideal deceased donors (control group). RESULTS: After a follow-up of three yr, death-censored graft survival was 100% in both groups. The calculated creatinine clearance was lower in the study group at six months (53 vs. 71 mL/min; p = 0.01) and similar at 12 months (68 vs. 68 mL/min; p = 0.48), 24 months (81 vs. 70 mL/min; p = 0.58), and 36 months (74 vs. 69 mL/min; p = 0.59). Urinary albumin/creatinine ratios were comparable between the two groups up to two yr. At three yr, urinary albumin/creatinine ratios were higher in the study group than the control group (10.5 vs. 0.9 mg/mmol; p = 0.007). Surveillance biopsies at three and six months post-transplant revealed no evidence for focal segmental glomerulosclerosis in the study group. CONCLUSIONS: Transplantation of single pediatric kidneys from donors weighing 10-14 kg into adult recipients provides excellent intermediate-term outcomes. Low-grade albuminuria, three yr post-transplant, might indicate late-onset hyperfiltration injury.


Assuntos
Nefropatias/cirurgia , Transplante de Rim , Complicações Pós-Operatórias , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Pré-Escolar , Feminino , Seguimentos , Taxa de Filtração Glomerular , Glomerulosclerose Segmentar e Focal/diagnóstico , Glomerulosclerose Segmentar e Focal/etiologia , Humanos , Lactente , Nefropatias/complicações , Nefropatias/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Adulto Jovem
10.
Swiss Med Wkly ; 142: w13672, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22949267

RESUMO

BACKGROUND: A high prevalence of vitamin D insufficiency has been found in the general population, in patients with chronic kidney disease and in kidney transplant patients. During winter there is a higher prevalence of vitamin D insufficiency due to the lack of solar ultraviolet B (UVB) exposure. Kidney transplant patients are advised to avoid sun exposure because of their high risk of skin cancer. This is considered to be one of the main reasons for the very high prevalence of vitamin D insufficiency in these patients. Whether circannual rhythm of vitamin D is totally reversed in kidney transplant patients is not known. METHODS: In this single centre prospective observational study, 50 kidney transplant patients visiting our outpatient clinic in January and February 2011 were included. Serum concentration of 25-hydroxvitamin D (25[OH]D), 1-25-hydroxvitamin D (1-25[OH]D) and intact parathormone (iPTH) were measured at study entry and 6 months later in summer. RESULTS: A total of 90% (45/50) of the study population had vitamin D deficiency 25(OH)D (<50 nmol/l) during winter. There was a rise of 25(OH)D in 94% (47/50) of patients from winter to summer (p <0.0001) leading to a decline of 25(OH)D deficiency from 90 to 60%, to a rise of 25(OH)D insufficiency from 6 to 26% and normal 25(OH)D from 4 to 14%, respectively (p = 0.0024). CONCLUSIONS: Vitamin D insufficiency during winter is very common in kidney transplant patients at our centre. Despite avoidance of exposure to UVB there is a preserved circannual rhythm of vitamin D in kidney transplant patients.


Assuntos
Transplante de Rim , Periodicidade , Complicações Pós-Operatórias , Deficiência de Vitamina D/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/diagnóstico , Estudos Prospectivos , Estações do Ano , Luz Solar , Inquéritos e Questionários , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/diagnóstico
11.
Nat Genet ; 44(8): 910-5, 2012 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-22772369

RESUMO

Chronic kidney disease (CKD) represents a major health burden. Its central feature of renal fibrosis is not well understood. By exome sequencing, we identified mutations in FAN1 as a cause of karyomegalic interstitial nephritis (KIN), a disorder that serves as a model for renal fibrosis. Renal histology in KIN is indistinguishable from that of nephronophthisis, except for the presence of karyomegaly. The FAN1 protein has nuclease activity and acts in DNA interstrand cross-link (ICL) repair within the Fanconi anemia DNA damage response (DDR) pathway. We show that cells from individuals with FAN1 mutations have sensitivity to the ICL-inducing agent mitomycin C but do not exhibit chromosome breakage or cell cycle arrest after diepoxybutane treatment, unlike cells from individuals with Fanconi anemia. We complemented ICL sensitivity with wild-type FAN1 but not with cDNA having mutations found in individuals with KIN. Depletion of fan1 in zebrafish caused increased DDR, apoptosis and kidney cysts. Our findings implicate susceptibility to environmental genotoxins and inadequate DNA repair as novel mechanisms contributing to renal fibrosis and CKD.


Assuntos
Reparo do DNA/genética , Exodesoxirribonucleases/genética , Mutação , Nefrite Intersticial/genética , Insuficiência Renal Crônica/genética , Animais , Linhagem Celular , Dano ao DNA , Endodesoxirribonucleases , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Técnicas de Silenciamento de Genes , Genes Recessivos , Teste de Complementação Genética , Humanos , Enzimas Multifuncionais , Nefrite Intersticial/complicações , Nefrite Intersticial/metabolismo , Nefrite Intersticial/patologia , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/metabolismo , Peixe-Zebra/anormalidades , Peixe-Zebra/genética
12.
BMJ Case Rep ; 20102010 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-22798090

RESUMO

A 67-year-old woman was admitted to the hospital due to progressive mental changes, nausea and vomiting after a dose increase of an intrathecal morphine pump. We found severe hypercalcaemia due to milk alkali syndrome (MAS). Her symptoms resolved quickly after normalisation of hypercalcaemia. Similar to the original and the modern versions of the syndrome, ingested carbonate was the main source of bicarbonate in our case. The main trigger was a morphine overdose with volume contraction due to vomiting and a further aggravation of chronic compensatory elevation of bicarbonate due to hypoventilation leading to MAS; thus, suggesting hypoventilation as a risk factor for MAS.


Assuntos
Carbonato de Cálcio/efeitos adversos , Hipercalcemia/induzido quimicamente , Hipoventilação/complicações , Osteoporose Pós-Menopausa/tratamento farmacológico , Inibidores de Simportadores de Cloreto de Sódio/efeitos adversos , Idoso , Analgésicos Opioides/efeitos adversos , Analgésicos Opioides/uso terapêutico , Dor nas Costas/tratamento farmacológico , Carbonato de Cálcio/uso terapêutico , Diagnóstico Diferencial , Relação Dose-Resposta a Droga , Feminino , Humanos , Hipercalcemia/diagnóstico , Bombas de Infusão , Injeções Espinhais , Assistência de Longa Duração , Morfina/administração & dosagem , Morfina/efeitos adversos , Fatores de Risco , Inibidores de Simportadores de Cloreto de Sódio/uso terapêutico
13.
Am J Pathol ; 163(3): 985-92, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12937139

RESUMO

Amplification of chromosomal regions leads to an increase of DNA copy numbers and expression of oncogenes in many human tumors. The identification of tumor-specific oncogene targets has potential diagnostic and therapeutic implications. To identify distinct spectra of oncogenic alterations in ovarian carcinoma, metaphase comparative genomic hybridization (mCGH), array CGH (aCGH), and ovarian tumor tissue microarrays were used in this study. Twenty-six primary ovarian carcinomas and three ovarian carcinoma cell lines were analyzed by mCGH. Frequent chromosomal overrepresentation was observed on 2q (31%), 3q (38%), 5p (38%), 8q (52%), 11q (21%), 12p (21%), 17q (21%), and 20q (52%). The role of oncogenes residing in gained chromosomal loci was determined by aCGH with 59 genetic loci commonly amplified in human tumors. DNA copy number gains were most frequently observed for PIK3CA on 3q (66%), PAK1 on 11q (59%), KRAS2 on 12p (55%), and STK15 on 20q (55%). The 11q13-q14 amplicon, represented by six oncogenes (CCND1, FGF4, FGF3, EMS1, GARP, and PAK1) revealed preferential gene copy number gains of PAK1, which is located at 11q13.5-q14. Amplification and protein expression status of both PAK1 and CCND1 were further examined by fluorescence in situ hybridization and immunohistochemistry using a tissue microarray consisting of 268 primary ovarian tumors. PAK1 copy number gains were observed in 30% of the ovarian carcinomas and PAK1 protein was expressed in 85% of the tumors. PAK1 gains were associated with high grade (P < 0.05). In contrast, CCND1 gene alterations and protein expression were less frequent (10.6% and 25%, respectively), suggesting that the critical oncogene target of amplicon 11q13-14 lies distal to CCND1. This study demonstrates that aCGH facilitates further characterization of oncogene candidates residing in amplicons defined by mCGH.


Assuntos
Carcinoma/genética , Neoplasias Ovarianas/genética , Proteínas Serina-Treonina Quinases/genética , Mapeamento Cromossômico , Cromossomos Humanos Par 11/genética , Ciclina D1/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Metáfase , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Serina-Treonina Quinases/metabolismo , Células Tumorais Cultivadas , Quinases Ativadas por p21
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