Matrix Calculi Research Articles

Matrix calculi in systemic lupus erythematosus complicated by distal renal tubular acidosis in a solitary kidney

Matrix calculi in systemic lupus erythematosus complicated by distal renal tubular acidosis in a solitary kidney

Dilute povidone-iodine irrigation during percutaneous nephrolithotomy to reduce postoperative infective complications - Is there any benefit?

Infectious complications following stone lithotripsy is a significant source of patient morbidity and mortality. Post percutaneous nephrolithotomy fever is reported in 37% of patients undergoing PCNL and sepsis is the most common cause of mortality following PCNL. Thus, there is an urgent need to tackle lithotripsy-associated bacteremia occurring intraoperatively, keeping in mind the threat of emerging global antibiotic resistance. The aim of our study was to study the efficacy of using intermittent 0.35% dilute Povidone-Iodine (PI) irrigation during PCNL in reducing postoperative infection rate. This is a prospective observational study done in 24 patients diagnosed with Staghorn and matrix calculi requiring PCNL. All patients were taken up for the procedure with sterile urine culture or after treating them with culture-specific antibiotic with initial positive urine culture. Intraoperative pelvic urine was sent for culture and sensitivity. 0.35% dilute PI irrigation was used intermittently during the procedure. Patients were monitored and assessed for signs of post-PCNL infection and PI-related side effects. The results were compared with similar group of patients with similar stone characteristics who underwent PCNL before adopting the dilute PI irrigation protocol (non-PI irrigation group). Among 24 patients, 18 patients had partial or complete Staghorn and 6 had matrix calculi. Five patients with Staghorn and three patients with matrix calculi had positive renal pelvic urine culture. In the non-PI irrigation group, 19 patients had Staghorn stones and 5 had matrix calculi. Three patients with Staghorn and two patients with matrix calculi had positive renal pelvic urine culture. Three patients (12.5%) had postoperative fever in the dilute PI irrigation group, compared to 11 patients (45.8%) in the non-PI irrigation group. No patient had PI-related complications. Our prospective study highlights that the use of 0.35% dilute PI irrigation intermittently during PCNL reduces the postoperative infection rate significantly.

Matrix Calculi in the Urinary Tract- A Prospective Cohort Study

Introduction: Matrix calculi are infrequently encountered in the urinary tract. Their biochemical composition and unusual radiological appearance make it difficult to differentiate them from fungal balls or tumours of the urinary tract. Aim: To study radiological, biochemical and microbiological characteristics of matrix calculi in the urinary tract and their management. Materials and Methods: This prospective observational cohort study was conducted at a tertiary care hospital, from July 2016 to August 2019. Analysis of the clinical, radiological and biochemical profiles of patients who were found to have matrix renal or ureteric calculi was done. These patients underwent Percutaneous Nephrolithotomy (PCNL) or Ureteroscopic Lithotripsy (URSL) and the stone material evacuated was sent for analysis. Data was analysed using Microsoft Excel, version 2016. Results: Matrix urinary stones were found in a total of 21 patients, out of which 15 were renal matrix calculi and six were ureteric matrix calculi. Mean age of the patient population was 44.5 years. Male to female ratio was 1.33:1. Total 7 (33.3%) patients were found to have Chronic Kidney Disease (CKD). The mean radiodensity of all the stones was 403 Hounsfield Unit (HU). Six patients also had a concomitant crystalline calculus. Histopathological analysis of these matrix calculi revealed an amorphous lamellated appearance. The postoperative course of all the patients was uneventful. One patient presented with a non matrix stone in the opposite kidney after one year of follow-up. Conclusion: Matrix calculi of the urinary tract are usually radiolucent on plane radiographs and have a low radiodensity on Computerised Tomography (CT) scan. Biochemical analysis of these calculi shows protein to be the predominant component. These calculi are more often seen in patients with Diabetes Mellitus (DM) or CKD and are frequently associated with a positive urine culture. They can be managed successfully with a combination of PCNL and URSL. Complete clearance is necessary to minimise recurrence.

Tubeless percutaneous nephrolithotomy: 3 years of experience with 454 patients

To present our experience with 454 patients who had tubeless percutaneous nephrolithotomy (TPCNL) over last 3 years. From September 2004 to August 2007, all patients aged >14 years and undergoing PCNL were considered for TPCNL. Exclusion criteria were the presence of pyonephrosis, matrix calculi, significant bleeding or residual stone burden and need for three of more percutaneous accesses. These patients had a nephrostomy tube placed after PCNL (control group). The remaining patients undergoing TPCNL (study group) had antegrade ureteric stenting. Demographic and perioperative data were compared retrospectively. Of 840 patients who had PCNL during the study period, 454 had TPCNL. The two groups had comparable demographic data except for a smaller stone burden (322.8 vs 832.2 mm(2)) and fewer staghorn calculi (94 vs 154) in patients undergoing TPCNL (P < 0.001). The mean number of tracts per renal unit and operative duration were statistically higher in patients undergoing standard PCNL (1.5 vs 1.1, and 68.8 vs 52.2 min, respectively). The decrease in haemoglobin, complication and stone-free rates were comparable. TPCNL was associated with less postoperative pain, analgesia requirement and earlier discharge (P < 0.001). TPCNL can be used with a favourable outcome and no increase in complications in selected patients, with the potential advantages of decreased postoperative pain, analgesia requirement and hospital stay. Its application can be extended to patients with a solitary kidney, previous ipsilateral open surgery, raised serum creatinine level, in the presence of three renal accesses or supracostal access, and in patients undergoing bilateral synchronous PCNL or contralateral endourological stone treatment.

The management of renal matrix calculi: a single‐centre experience over 5 years

To define incidence of renal matrix calculi in patients undergoing percutaneous nephrolithotomy (PCNL), and describe its clinical, laboratory and radiological features; we also studied the efficacy of PCNL in managing this rare entity. We retrospectively reviewed the records of 1368 PCNLs performed from April 2003 to March 2008, and identified 17 patients (mean age 44.3 years; 11 women and six men) having matrix calculi. The patients' clinical, laboratory and radiological features were studied, and the perioperative outcome and follow-up data analysed. Flank pain was commonest mode of presentation (15) followed by recurrent urinary tract infection (five). Pyuria was present in 14 patients and urine culture showed significant growth in 10. A plain X-ray showed a small radio-opaque calculus (10 renal units) and faint laminated calcification (four). Intravenous urography showed a filling defect and non-visualized system in nine and five patients, respectively. Non-contrast computed tomography and magnetic resonance urography diagnosed calculi in two and one patient, respectively, on haemodialysis. PCNL was abandoned initially in four patients due to pyonephrosis. The mean hospital stay was 3.4 days and decrease in haemoglobin was 0.89 g/dL. One patient developed sepsis. Of 11 stones analysed, two were composed entirely of proteins and the remaining nine had crystalline components. At a mean follow-up of 12.6 months, no patients had recurrence of stone. Matrix calculi occurred in 1.24% of patients undergoing PCNL. Although considered radiolucent, plain X-ray showed a small radio-opaque calculi or faint laminated calcifications in 10 of 17 patients. PCNL rendered patients stone-free with minimum morbidity.

The University of Michigan Experience with Percutaneous Nephrostolithotomy for Urinary Matrix Calculi

To evaluate commonalities in presentation and long-term efficacy of treatment by percutaneous nephrostolithotomy of matrix stones, a rare form of urinary calculi. The clinical data of 9 consecutive patients with urinary matrix calculi in 11 kidneys treated at our institution between 1995 and 2007 were retrospectively reviewed. The matrix component in all 11 kidneys was successfully treated with percutaneous nephrostolithotomy, with few complications. Among 8 patients (9 kidneys) with follow-up, none has had recurrence of matrix stones after a mean follow-up of 3.8 years. Along with previously known risk factors for matrix stones, such as urinary tract infections and renal insufficiency, we identified smoking as another possible risk factor. Long-term antimicrobial prophylaxis was used in only 1 patient and thus does not seem necessary for prevention of recurrence. Matrix stone treatment with percutaneous nephrostolithotomy is durable and should remain the treatment modality of choice.

Retroperitoneoskopische Pyelotomie zur Extraktion eines amorphen Matrixausgusssteins der rechten Niere

The female patient underwent multiple extracorporal shockwave treatments and an ureterorenoscopy during which an amorphous renal mass was found. A retroperitoneoscopy was performed with extraction of a large amorphous matrix calculus. Today, the prevalence of matrix calculi is very low. They are associated with and caused by urinal-infections. Delayed diagnosis in radiological-imaging procedures is typical for these stones. The minimal-invasive approach via retroperitoneoscopy seems to be an intriguing alternative to the established procedures like percutaneous nephrolitholapaxy.

5561944 Method and apparatus for enhancing the growth and quality of edible plants : Ismail Sooliman; Sacks Brian Johannesburg, South Africa assigned to African Oxygen Limited

Concentric laminations, radial striations, frond formation and spherules are morphologic characteristics of native human concretions occurring in any segment of the urinary conduits from nephron to external meatus. The organic matrix is invariably so structurally related to these gross physical characteristics as to justify the assumption that it has a definitive architectonic role in the morphology of all concretions. Intermolecular bonding between matrix molecules appears to be established by gross, histological and electron microscopic examination.Matrix composition is remarkably constant for calculi of any type of crystalline content. The molecular composition is predominantly of molecules of low molecular weight, high solubility in their native states, and relatively low concentration in the urine of patients who form calculi. Selectivity is clearly a factor in matrix formation from urinary macromolecules.Matrix deposition unquestionably precedes crystal formation in all forms of experimental intranephronic calculosis. The occurrence of “matrix calculi” and recrystallization of decrystallized cystine stone matrices suggest that matrix precedes crystal deposition in at least some human concretions.Calcium and phosphate are universally present in calculus matrix even after all microscopic or petrographically demonstrable crystals have been removed. Mineralization in terms of inorganic ion accretion by matrix is a distinct possibility. This may play a role in concrement formation by decreasing the solubility of matrix molecules. The molecular epitactic nucleation of hydroxyapatite may well be a characteristic of the majority if not of all calculus matrices.

Understanding radio polarimetry. I. Mathematical foundations

The measurement of polarized radiation uses entirely different methods at optical and radio wavelengths. As a result, the algebraic analysis of polarimeter performance differs and, in the case of radio interferometry, is unnecessarily complicated. We demonstrate that the mathematical operation of outer matrix multiplication provides the missing link between the two approaches. Within one coherent framework, we then unite the concepts of Stokes parameters and Wolf coherency matrix, the Jones and Mueller calculi from optics, and the techniques of radio interferometry based on multiplying correlators. We relate the polarization performance of a complete radio interferometer to the (matrix) polarization properties of its successive signal processing stages, providing a clear view of how a radio polarimeter works. Our treatment also clarifies the nature of and the relations between the various types of transformations used in optical polarimetry. We develop the analysis from the radio interferometrist's point of view, but include enough background for a wider audience. In a companion paper, we discuss in more detail the application to the calibration of radio interferometer systems; in a third paper we investigate the IAU (1973) radio definition of the Stokes parameters and its precise translation into mathematical form.

751 - Matrix Calculi - The Malignant Variant of Urolithiasis

No AccessJournal of Urology1 Jun 1987Matrix Calculi - The Malignant Variant of Urolithiasis Claus Fischer, Lothar Hertle, Jobst Pastor, and Theodor Senge Claus FischerClaus Fischer More articles by this author , Lothar HertleLothar Hertle More articles by this author , Jobst PastorJobst Pastor More articles by this author , and Theodor SengeTheodor Senge More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(17)75901-0AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail "Matrix Calculi - The Malignant Variant of Urolithiasis." The Journal of Urology, 137(6), p. 291A © 1987 by The American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 137Issue 6June 1987Page: 291A Advertisement Copyright & Permissions© 1987 by The American Urological Association Education and Research, Inc.MetricsAuthor Information Claus Fischer More articles by this author Lothar Hertle More articles by this author Jobst Pastor More articles by this author Theodor Senge More articles by this author Expand All Advertisement PDF DownloadLoading ...

Childhood urolithiasis in the United Kingdom and Eire.

152 children with urinary calculi were treated in the United Kingdom and Eire in the years 1972 and 1973. There was a marked male preponderance particularly evident in early life. In 124 children the urine was infected on admission to hospital; in 87, particularly the younger children, this was with the Proteus species. Awareness of the relationship between Proteus urinary infection and matrix calculi is stressed.

The Theory of Polarization Phenomena

B A Robson London: Oxford University Press 1975 pp viii + 119 price £5.50 Some decades back Jones and Mueller developed their distinctive matrix calculi for treating polarization effects in classical optics, building on techniques reaching back to Stokes more than a century ago. In this little book the author describes the extension of these methods to the study of polarization phenomena, for spin ½ and spin 1 particles in particular, but with appropriate generalization to systems of arbitrary spin.

Matrix calculi $SS1M$ and $SS1I$ compared with axiomatic systems.

Matrix calculi $SS1M$ and $SS1I$ compared with axiomatic systems.

Index ranges for matrix calculi

The paper describes a scheme for symbolic manipulation of index expressions which arise as a by-product of the symbolic manipulation of expressions in the matrix calculi described by the authors in a previous paper. This scheme attempts program optimization by transforming the original algorithm rather than the machine code. The goal is to automatically generate code for handling the tedious address calculations necessitated by complicated data structures. The paper is therefore preoccupied with “indexing by position.” The relationship of “indexing by name” and “indexing by position” is discussed.

Organic matrix of human urinary concretions

Concentric laminations, radial striations, frond formation and spherules are morphologic characteristics of native human concretions occurring in any segment of the urinary conduits from nephron to external meatus. The organic matrix is invariably so structurally related to these gross physical characteristics as to justify the assumption that it has a definitive architectonic role in the morphology of all concretions. Intermolecular bonding between matrix molecules appears to be established by gross, histological and electron microscopic examination. Matrix composition is remarkably constant for calculi of any type of crystalline content. The molecular composition is predominantly of molecules of low molecular weight, high solubility in their native states, and relatively low concentration in the urine of patients who form calculi. Selectivity is clearly a factor in matrix formation from urinary macromolecules. Matrix deposition unquestionably precedes crystal formation in all forms of experimental intranephronic calculosis. The occurrence of “matrix calculi” and recrystallization of decrystallized cystine stone matrices suggest that matrix precedes crystal deposition in at least some human concretions. Calcium and phosphate are universally present in calculus matrix even after all microscopic or petrographically demonstrable crystals have been removed. Mineralization in terms of inorganic ion accretion by matrix is a distinct possibility. This may play a role in concrement formation by decreasing the solubility of matrix molecules. The molecular epitactic nucleation of hydroxyapatite may well be a characteristic of the majority if not of all calculus matrices.