Acute Tubulo-interstitial Nephritis with Positive Anti-Neutrophil Cytoplasmic Antibodies

Introduction: Anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis involving the kidney usually comprises pauci-immune, necrotizing glomerulonephritis with crescents. Mononuclear tubulo-interstitial infiltrates are common in ANCA associated vasculitis, but these have usually been described in conjunction with glomerulitis. Acute tubulo-interstitial nephritis (ATIN) is a common cause of acute kidney injury that is most frequently induced by drugs or infections. Idiopathic ATIN has rarely been reported in association with the presence of a positive ANCA. These two entities seem to share a common immunological basis.Case report: We report a 75 years-old male patient who presented with acute kidney injury and his serum tested positive for p-ANCA by indirect immunofluoresence with a titer of 1/320. Testing by ELISA demonstrated anti-myeloperoxidase (MPO) specificity with a level of 28.8 IU/mL. His kidney biopsy showed features of ATIN with no glomerular involvement. Treatment with corticosteroids led to improvement of his kidney function and serology for ANCA became negative. In this case report ATIN seems to be associated with ANCA positivity, in the absence of other obvious causes for the acute tubulo-interstitial insult.Conclusion: ATIN can be associated with positive ANCA without features of renal-limited vasculitis or systemic vasculitis. This can occur in the absence of drug exposure. The outcome in our case was favorable with corticosteroid therapy.Key words: ANCA; Acute Tubulo-interstitial Nephritis; Pathogenesi

Abcès hypophysaire chez un hémodialysé chronique traité médicalement : à propos d’une observation

L’abcès hypophysaire est une pathologie rare et fatale en absence de traitement adéquat .Il est à évoquer devant un tableau clinique  d’hypertension intracrânienne, une dysrégulation hormonale hypophysaire et un contexte infectieux. Une conduite thérapeutique basée sur une  antibiothérapie pourrait être tenté si diagnostic précoce. Nous rapportons un cas d’abcès hypophysaire survenant chez un hémodialysé chronique pris en charge par une antibiothérapie seule dont l’évolution était favorable avec un recul de 2 ans

Myelodysplastic syndrome and extracapillary glomerulonephritis: is there a link?

Introduction: The association of myelodysplastic syndrome and extracapillary glomerulonephritis is exceptional. Only two other cases have been reported.Reported case: A 52-year-old patient with a history of myelodysplastic syndrome developed rapidly progressive glomerulonephritis. Renal biopsy identified extracapillary glomerulonephritis.Discussion: The association of myelodysplastic syndrome with glomerulopathy is rare and often regarded as fortuitous. Only a few cases are described in literature on the subject. A relationship between the two diseases is possible but the causal link between these two diseases remains unknown.Conclusion: The notion that myelodysplastic syndrome may be associated with various glomerular nephropathies involves looking for renal disease in this haematologic disorder

Scleroderma Renal Crisis Precipitated by Steroid Treatment in Systemic Lupus Erythematosus and Scleroderma Overlap Syndrome

Introduction: Connective tissue disorders can overlap in various ways. Patients may present with features of more than one specific disease without satisfying the diagnostic criteria and thereafter evolve into a specific disease entity. Occasionally, patients may fulfil simultaneouslythe diagnostic crateria of two or more diseases. Several cases of systemic sclerosis (SSc) and systemic lupus erythematosus (SLE) overlap syndrome have been reported. SLE patients often develop lupus nephritis, the treatment of which is based on immunosuppression with corticosteroids (CS) and cytotoxic drugs. However, the use of high dose of CS has been associated with scleroderma renal crisis (SRC) in patient with SSc.Case report: a 43-year-old woman presented to the nephrology department of the Military hospital in Rabat, Morocco, in August 2011 with progressive dyspnea and oliguria. She was diagnosed as SLE and scleroderma overlap syndrome based on clinical and serologicalmarkers. Renal biopsy showed lupus nephritis. Immunosuppression consisting of high-dose steroid and cyclophosphamide pulses was given. There was response to treatment but 15 days later the course of the disease was complicated by scleroderma renal crisis evidencedby elevated blood pressure, deteriorating kidney function, hemolysis and thrombocytopenia. The patient was treated with perindopril and rapid reduction of steroid doses. This was followed by correction of hemolysis and thrombocytopenia. Two months later, the patient was off dialysis, but had chronic renal insufficiency with an estimated GFR of 25 ml/minute.Conclusion: This report describes the occurrence of SRC in a patient with lupus nephritis and SSc/SLE overlap syndrome who was treated by CS andcyclophosphamide

La grossesse chez les hémodialysées chroniques

La survenue d'une grossesse en hémodialyse chronique (HDC) est rare, mais depuis la description du premier cas par Confortini en 1971, plusieursobservations ont été rapportées. L'hémodialyse a considérablement  amélioré la fertilité de ces patientes. Nous rapportons l'expérience de  douze grossesses survenues entre 1999 et 2014, chez douze patientes d'âge médian 34 ans (22-44), en hémodialyse (HD) depuis 40 mois  (3-72), l'âge gestationnel moyen de diagnostic est de 16 semaines  d'aménorrhée, la grossesse était compliquée dans 50% des cas par un hydramnios. Le terme moyen est de 35 semaine d'aménorrhée (SA) et l'accouchement a été réalisé dans 90% des grossesses par voie basse. Le poids moyen des nouveau-nés est de 1800g. De telles grossesses sont à haut risque du fait de la fréquence des complications. Elles devraient être contrôlées par les équipes multidisciplinaires, et la consultation prénatal ne devrait pas être négligée. L'objectif de ce travail est de rapporter notre expérience concernant la survenue d'une grossesse chez les patientes dialysées et de la confronter aux données de la littérature

Profil des insuffisants rénaux chroniques diabétiques à l’initiation de l’hémodialyse au service de néphrologie et dialyse de l’hôpital militaire de Rabat, Maroc

Le diabète constitue une cause fréquente d'insuffisance rénale chronique terminale (IRCT) dans le monde. Ce travail présente une étude clinique rétrospective dont le but est de décrire le profil clinico-biologique des patients diabétiques en IRCT, de le comparer aux patients non-diabétiques au stade d'IRCT, et de suivre l'évolution de leurs abords vasculaires, afin d'en déduire des conclusions sur une prise en charge particulière des patients diabétiques. Les paramètres cliniques et biologiques concernant les patients mis en hémodialyse dans notre formation entre le 01 janvier 2006 et le 31 décembre 2011, ont été recueilli et analysés. Nous avons procédé à l'étude comparative des patients en fonction de l'existence ou non d'une néphropathie diabétique, et nous nous sommes intéressés à l'évolution de leurs abords vasculaires. Il s'agit de 207 patients insuffisants rénaux chroniques, dont 86 diabétiques. Le groupe des patients diabétiques était moins suivi avant la mise en hémodialyse (3,66 mois vs. 6,32 mois), avec une prise beaucoup plus importante d'antihypertenseurs (1,87 vs. 1,14, p<0,001). L'échec des abords vasculaires était plus important chez les patients diabétiques (45% vs. 27%, p=0,006), avec une survie moyenne plus faible de leurs abords vasculaires (509 vs 753 jours, p=0,003). L'étude comparative des taux d'hémoglobine, de parathormone intacte, d'albuminémie et de C-réactive protéine, entre le groupe de patients diabétiques et non diabétiques était non significative. Notre étude soulève le problème du suivi néphrologique chez les diabétiques, pourtant censés être mieux suivis, et son retentissement sur l'avenir de leurs abords vasculaires.Key words: Diabète, insuffisance rénale chronique, hémodialys

Emulsion copolymerization of styrene and butyl acrylate in the presence of a chain transfer agent. Part 2: parameters estimability and confidence regions

Accurate estimation of the model parameters is required to obtain reliable predictions of the products end-use properties. However, due to the mathematical model structure and/or to a possible lack of measurements, the estimation of some parameters may be impossible. This paper will focus on the case where the main limitations to the parameters estimability are their weak effect on the measured outputs or the correlation between the effects of two or more parameters. The objective of the method developed in this paper is to determine the subset of the most influencing parameters that can be estimated from the available experimental data, when the complete set of model parameters cannot be estimated. This approach has been applied to the mathematical model of the emulsion copolymerization of styrene and butyl acrylate, in the presence of n-dodecyl mercaptan as a chain transfer agent. In addition, a new approach is used to better assess the true confidence regions and evaluate the accuracy of the parameters estimates in more reliable way

Dynamic simulation of hybrid differential algebraic systems using GPROMS: case study in emulsion polymerization

This paper is deals with dynamic simulation of a semi-batch polymerization reactor for emulsion copolymerization of styrene and butyl acrylate in the presence of n-dodecyl mercaptan as chain transfer agent (CTA). Mathematical model of the polymerization reaction involved is used to predict the glass transition temperature of produced polymer, global monomer conversion, the number and weight average molecular weights, the particle size distribution and the amount of residual monomers. This model, a set of hybrid differential algebraic equations (DAEs), is implemented into gPROMS environment for modeling, simulation, and optimization

Estimability analysis and parameter identification for a batch emulsion copolymerization reactor in the presence of a chain transfer agent

In this paper we have developed an estimability analysis method to identify the subset of potentially estimable parameters from the proposed experimental data. The emulsion copolymerization model involves 59 unknown parameters. The complete set of parameters cannot be estimated from the experimental measurements available. Thanks to the method developed, 21 parameters were selected and identified. The non estimable parameters were set to nominal values taken from literature. The mathematical model was validated under both batch and fed batch conditions

Analysis of optimal operation of a fed-batch emulsion copolymerization reactor used for production of particles with core-shell morphology

In this paper dynamic optimization of a lab-scale semi-batch emulsion copolymerization reactor for styrene and butyl acrylate in the presence of a chain transfer agent (CTA) is studied. The mathematical model of the process, previously developed and experimentally validated, is used to predict the glass transition temperature of produced polymer, the number and weight average molecular weights, the monomers global conversion, the particle size distribution, and the amount of residual monomers. The model is implemented within gPROMS environment for modeling and optimization. It is desired to compute feed rate profiles of pre-emulsioned monomers, inhibitor and CTA that will allow the production of polymer particles with prescribed core-shell morphology with high productivity. The results obtained for different operating conditions and various additional product specifications are presented. The resulting feeding profiles are analyzed from the perspective of the nature of emulsion polymerization process and some interesting conclusions are drawn