Prevalence of vitamin D deficiency in peritoneal dialysis patients.

Peritoneal dialysis (PD) patients have a high risk of developing vitamin D deficiency as 25(OH) vitamin D, the precursor of active vitamin D, is lost during dialysis. This cross-sectional study was conducted to investigate the prevalence of vitamin D deficiency among adult Saudi patients on regular PD The data was collected in the summer of 2010 from patients who were on PD for more than six months at the King Khalid University Hospital, Riyadh. We recorded the demographic and clinical parameters for all patients. Blood samples were taken for serum vitamin D level (25 OH), serum parathyroid hormone (PTH) levels and other necessary biochemical parameters. There were 27 patients (11 males and 16 females) with a mean age of 46 (15-78 ± 21) years. Five patients were on continuous ambulatory PD and 22 patients were using automated PD. The average time on PD was 27.5 (6-84 ± 18.5) months. The mean serum vitamin D 25 (OH) level was 16.1 (4.9-41.5 ± 8.23) nmol/L. Sixteen (59.2%) of the patients had levels below 15 nmol/L, while another eight patients (29.6%) had vitamin D levels between 15 and 25 nmol/L, indicating a marked deficiency. The mean serum calcium was 2.2 (1.7-2.6 ± 0.2) mmol/L and the mean serum phosphorous was 1.48 (0.64-2.22 ± 0.37) mmol/L. Fifteen patients (55.5%) had significant hyperparathyroidism (serum PTH levels above 30 pmol/L). Majority of the PD patients in our center had vitamin D deficiency. The possible reasons include chronic renal failure, dietary restrictions, loss of vitamin D and decreased exposure to sunlight.

Validation of predictive equations for glomerular filtration rate in the Saudi population.

Predictive equations provide a rapid method of assessing glomerular filtration rate (GFR). To compare the various predictive equations for the measurement of this parameter in the Saudi population, we measured GFR by the Modification of Diet in Renal Disease (MDRD) and Cockcroft-Gault formulas, cystatin C, reciprocal of cystatin C, creatinine clearance, reciprocal of creatinine, and inulin clearance in 32 Saudi subjects with different stages of renal disease. We compared GFR measured by inulin clearance and the estimated GFR by the equations. The study included 19 males (59.4%) and 13 (40.6%) females with a mean age of 42.3 +/- 15.2 years and weight of 68.6 +/- 17.7 kg. The mean serum creatinine was 199 +/- 161 micromol/L. The GFR measured by inulin clearance was 50.9 +/- 33.5 mL/min, and the estimated by Cockcroft-Gault and by MDRD equations was 56.3 +/- 33.3 and 52.8 +/- 32.0 mL/min, respectively. The GFR estimated by MDRD revealed the strongest correlation with the measured inulin clearance (r= 0.976, P= 0.0000) followed by the GFR estimated by Cockcroft-Gault, serum cystatin C, and serum creatinine (r= 0.953, P= 0.0000) (r= 0.787, P= 0.0001) (r= -0.678, P= 0.001), respectively. The reciprocal of cystatin C and serum creatinine revealed a correlation coefficient of 0.826 and 0.93, respectively. Cockroft-Gault formula overestimated the GFR by 5.40 +/- 10.3 mL/min in comparison to the MDRD formula, which exhibited the best correlation with inulin clearance in different genders, age groups, body mass index, renal transplant recipients, chronic kidney disease stages when compared to other GFR predictive equations.

Normal reference levels of serum cystatin C in Saudi adults.

This is the first report from Saudi Arabia studying the normal reference intervals in adult Saudi subjects and evaluating serum cystatin C as a prospective marker for the assessment of the glomerular filtration rate (GFR). Three hundred healthy adult Saudi subjects including 156 males (52%) and 144 females (48%), with a mean age of 31.21 +/- 9.82 years were prospectively studied to establish normal reference ranges for cystatin C. A total of 68.34% of the study patients were in the age-group of 21-40 years. The mean serum cystatin C in the 300 healthy subjects was 0.751 +/- 0.11 mg/L (0.50 - 1.09), increasing gradually with age: it was 0.738 +/- 0.11 mg/L (0.51 - 1.09) in the age-group 21 - 30 years and 0.807 +/- 0.12 (0.51 - 1.09) among subjects who were > 50 years of age. The mean serum cystatin C in females (0.778 +/- 0.118 mg/L) was significantly hig-her than in males (0.726 +/- 0.095 mg/L) (p < 0.0001). The serum cystatin C level was within the defined reference range of 0.53 - 0.95 mg/L in 95% of the subjects with a mean value of 0.74 +/- 0.097 mg/L, and was falling within the 95% confidence interval of 0.73865 - 0.7637 mg/L, and with 98.84% area under the curve (AUC). All the other renal function markers (urea, serum creatinine, calculated GFR, BMI) among the studied subjects were within the normal reference ranges for adult Saudi population. The serum cystatin C level had a significant correlation with the body mass index (BMI) (r = 0.155; p = 0.007) and a correlation with serum creatinine as well (r = 0.009; p = 0.873). It showed a negative correlation with calculated GFR as per Cockroft-Gault equation (r = - 0.101; p = 0.083).

Extraction of urinary bladder stone as described by Abul-Qasim Khalaf Ibn Abbas Alzahrawi (Albucasis) (325-404 H, 930-1013 AD). A translation of original text and a commentary.

This is a detailed study of the technique of cystolithotomy as practiced by the Muslim surgeon Alzahrawi (Albucasis) in Cordova more than 1000 years ago. In addition to translating the relevant chapter in his book Al-Tasreef, his technique is critically evaluated comparing it with that of his predecessors and his successors. The study confirmed the originality of Alzahrawi who described operative steps and invented operative instruments not known in the Greco-Roman era. He was also the first to describe, in details, the operative technique in women and to recommend the 2-stage operation in complicated cases. His modifications and innovations greatly influenced surgery in Middle Ages Europe up to the 18th century which witnessed the beginnings of the modern method using the suprapubic, instead of the perineal, approach. Alzahrawi's influence is vividly seen in the practice of the Italian lithotomist "Marianus Sanctus" (16th century), the French "Jack De Beaulieu" (17th century) and the English "Shelsden" (18th century). Alzahrawi is the founder of lithotripsy. He introduced Al-Kalaleeb forceps to crush large bladder stones and Al-Mishaab to drill and fragment an impacted urethral stone. Andreas a Cruce (18th century) only added screw action to Al-Kalaleeb lithotrite but Amussat managed in 1822 to apply it transurethrally. Similarly, by the notion of transurethrally getting at the stone while within the bladder, Alzahrawi's idea of drilling by Al-Mishaab was the foundation of the litholepte of Fournier de Lempdes (1812), the instrument of Gruithusien (1813), Civiale's trilabe (1818) and the brise coque of Rigal De Galliac (1829).

Non-typhoidal salmonella aortitis in a transplant patient.

Non-typhoidal salmonella bacteremia may result in extra gastrointestinal localization of infection. Aortitis due to non-typhoidal salmonella was reported to be the cause of 38-42.5% of all infected abdominal aortitis. Underlying atherosclersis is a frequent site for salmonella aortitis. We describe here a case of possible salmonella aortitis in a renal transplant patient.