Search PubMed⌕ Search

Biomedical subjects

Michael Straub

Publications and source records attributed to Michael Straub.

6 recordsLinked to original sources

Role and relevance of genetic testing in patients with kidney stones: a review from EAU Section of Endourology.

PURPOSE OF REVIEW: Kidney stones have a high heritability. More than 40 genes have been identified causing monogenic forms of kidney stone disease (KSD). Kidney stone formers with genetic variants implicated in monogenic forms of KSD often suffer from early onset, high recurrence rates, and chronic kidney disease. Some patients may also exhibit extrarenal disease requiring attention. RECENT FINDINGS: Recent analysis of KSD patients identified a likely monogenic cause in pediatric populations in 17-30% of participants while in adult unselected populations 2.7-8% had a positive finding. More patients carry single genetic variants in monogenic forms that are classically considered as autosomal recessive but may cause an intermediate genetic risk for the development of KSD possibly in interaction with environmental or lifestyle factors. Genome-wide association studies have identified additional risk loci associating with KSD. Their clinical relevance are currently investigated. Patients with recurrent kidney stone episodes may be at elevated risk of progressive chronic kidney disease. SUMMARY: Monogenic causes of KSD are prevalent in patients less than 25 years of age and in some patients with high-risk metabolic profiles. These patients should undergo genetic testing to enable a precise molecular genetic diagnosis and personalized therapy as well as family counseling and screening.

Humans↗

Rational evaluation of urinary stone disease.

This article outlines the recent state of the art in the metabolic diagnosis of stone disease. The current literature in the field of urolithiasis-including the existing German and EAU-Guidelines as well as the Conference Book of the 1st International Consultation on Stone Disease-was critically reviewed. As far as possible the references were rated according to the EBM criteria. The occurrence of stone disease in the western world is increasing greatly. Modern lifestyle, dietary habits and excess weight-problems of affluent societies-are emerging as the important promoters of the "stone boom" in the new millennium. This even affects children, whose stone prevalence is otherwise significantly less than that of adults. Criteria for the high-risk group of stone formers were clearly defined. A diagnostic standard is formulated for the basic and the elaborate metabolic evaluation of a stone patient. The diagnostic pathways for the most important stone types and metabolic disorders, respectively, are described. The present concept allows a precise risk classification of each stone former and facilitates the decision whether stone-specific measures in addition to the basic metaphylaxis are recommendable or not.

Adult↗

Effect of a pT0 cystectomy specimen without neoadjuvant therapy on survival.

BACKGROUND: In some cases of radical cystectomy for bladder cancer, no residual tumor is found in the cystectomy specimen (the pT0 classification). The aim of this study was to evaluate the outcome of such patients in a large cystectomy series. METHODS: All 900 patients with radical cystectomy and pelvic lymphadenectomy for TCC of the bladder in the period January 1986 to September 2003 who received no neoadjuvant therapy were included. Cystectomy specimens from 181 (20.1%) patients were graded as pT0. Complete follow-up was obtained in all cases. Tumor-specific survival (pT0 vs. pT+) was calculated with the Kaplan-Meier method and compared with the log-rank test. RESULTS: The rate of lymph node metastases in the pT0 group was 6.6%. pT0 status was found with Ta/is/1 in 36.8%, T2a in 41.8%, and T2b in 10.9%. The 169 patients with pT0pN0 tumors had 10-year tumor-specific survival rates of 91.0. There was no statistically significant survival benefit for pT0pN0 tumors compared with pT+pN0 tumors for maximal tumor classifications of pTa/pTis/pT1 and pT2b, but patients with a pT0T2apN0 tumor had a statistically significantly better tumor-specific survival than those with a pT2apN0 tumor (P = 0.002). No patient with a pT0pN0 tumor had a local recurrence. The rate of incidental second primary malignancies in a specimen was 15.5%. CONCLUSIONS: A pT0pN0 cystectomy specimen indicates a curative therapy, but there is a substantial risk of tumor recurrence. In the group of tumors with a maximal classification of pT2a, the pT0 tumors constitute a subgroup with a significantly higher likelihood of survival.

Combined Modality Therapy↗

Developments in stone prevention.

PURPOSE OF REVIEW: This review focuses on new developments in stone prevention. Unfortunately, no major progress in this field has happened. There is a worldwide lack of randomized and controlled trials, which could confirm our theoretical assumptions and preventive concepts in stone disease. With these preconditions in mind, this review presents the current knowledge of metabolic influences causing the symptom "stone" and the effective measures against it. RECENT FINDINGS: Modern lifestyle, dietary habits and obesity emerge to be the promoters of idiopathic stone disease. Cross-sectional studies showed significant correlations between these factors and kidney stones with direct implications on our preventive concepts: normalization of body mass index, adequate physical activity, balanced nutrition and sufficient circadian fluid intake. Modern diets containing a lot of animal protein, refined carbohydrates and salt act on the metabolism like an acid load. To overcome these disadvantageous effects, a sufficient supply of potassium and alkali is required. Last but not least, calcium should not be restricted. There is clear evidence from clinical and experimental research that a normal or a high calcium supply is appropriate in calcium stone disease. Only in absorptive hypercalciuria calcium restriction remains beneficial in combination with thiazide and citrate therapy. SUMMARY: Up to 85% of all stone patients could anticipate lower risk of stone recurrence with elementary reorientation of their lifestyle and dietary habits. Normalizing the major risk factors is easy and cheap. About 15% of patients forming stones require additional specific pharmacological prevention. The specific measures to avoid recurrence of the stone disease are precisely defined.

Calcium, Dietary↗

Postoperative resorptive and excretory capacity of the ileal neobladder.

OBJECTIVE: To assess the extent and mechanism of renal reabsorption and excretion in patients with an ileal neobladder, as mild metabolic acidosis cause by proton reabsorption is common after such surgery, and long-term pharmacological correction is often necessary. PATIENTS AND METHODS: The study comprised 30 patients (29 men and one woman) with ileal neobladders after oncological surgery; before surgery all had normal retention values. Before and after withdrawing the transurethral catheter, serum creatinine and urea were analysed and used to assess the effect of the neobladder on retention values, expressed as the percentage change from baseline (Delta creatinine and urea). RESULTS: There was a significant correlation between the Delta-creatinine and Delta-urea values (P < 0.001; r = 0.66); 15 patients (50%) showed resorption of creatinine and urea, eight (27%) excreted creatinine into the neobladder and resorbed urea from it at the same time, and three (10%) showed the reverse response, i.e. creatinine resorption and urea excretion. Interestingly, four patients (13%) excreted both creatinine and urea into the neobladder. CONCLUSIONS: We assume that there was both a resorptive and excretory function. Probably the metabolic state (resorption or secretion) of the neobladder depends on its mucus production and on the internal surface, or on diuresis. Further investigation is required to characterize these different influences.

Aged↗

A multicenter study of the morbidity of radical cystectomy in select elderly patients with bladder cancer.

PURPOSE: We evaluated the morbidity of radical cystectomy for invasive bladder cancer in select patients older than 75 years using recent data from 2 academic hospitals. MATERIALS AND METHODS: We analyzed 73 radical cystectomies performed from January 1995 to June 2000 in patients 75 to 89 years old (median age 79.3). Cases were categorized according to the American Society of Anesthesiologists classification with a score of 2 in 41, 3 in 30 and 4 in 2. External urinary diversion was performed in 51 cases and an ileal neobladder was constructed in 22. We evaluated the incidence and type of complications, clinical outcome, and postoperative care unit and hospital stay. Statistical analysis was done using the chi-square and Student t tests. RESULTS: Median operative time was 263 minutes (range 95 to 451). The perioperative mortality rate was 2.7%. The intraoperative, early and late postoperative complication rates were 38.4%, 46.5% and 16.4%, respectively. Three reoperations (4.1%) were necessary. The most common early complications were pyelonephritis in 12.3% of cases, disorientation in 10.9%, pneumonia in 8.2% and prolonged ileus in 12.3%. The most common late complications were ureteroileal anastomotic stenosis in 5 cases and hernia in 3. Median postoperative care unit and hospital stays were 12 and 34 days, respectively. At a median followup of 14.4 months (range 6 to 74) the overall mortality rate was 31.5%. Hospital stay was significantly higher in patients with complications. The incidence of complications was similar in the 2 groups. CONCLUSIONS: These data support the aggressive surgical management of bladder cancer in select elderly patients. A rigorous multidisciplinary team approach can provide acceptable perioperative morbidity.

Aged↗