Trends in renal calculus composition and 24-hour urine analyses in patients with neurologically derived musculoskeletal deficiencies

ABSTRACT Purpose: To better characterize metabolic stone risk in patients with neurologically derived musculoskeletal deficiencies (NDMD) by determining how patient characteristics relate to renal calculus composition and 24-hour urine parameters. Materials and Methods: We performed a retrospective cohort study of adult patients with neurologically derived musculoskeletal deficiencies presenting to our multidisciplinary Kidney Stone Clinic. Patients with a diagnosis of NDMD, at least one 24-hour urine collection, and one chemical stone analysis were included in the analysis. Calculi were classified as primarily metabolic or elevated pH. We assessed in clinical factors, demographics, and urine metabolites for differences between patients who formed primarily metabolic or elevated pH stones. Results: Over a 16-year period, 100 patients with NDMD and nephrolithiasis were identified and 41 met inclusion criteria. Thirty percent (12 / 41) of patients had purely metabolic calculi. Patients with metabolic calculi were significantly more likely to be obese (median body mass index 30.3kg / m2 versus 25.9kg / m2), void spontaneously (75% vs. 6.9%), and have low urine volumes (100% vs. 69%). Patients who formed elevated pH stones were more likely to have positive preoperative urine cultures with urease splitting organisms (58.6% vs. 16.7%) and be hyperoxaluric and hypocitraturic on 24-hour urine analysis (37mg / day and 265mg / day versus 29mg / day and 523mg / day). Conclusions: Among patients with NDMD, metabolic factors may play a more significant role in renal calculus formation than previously believed. There is still a high incidence of carbonate apatite calculi, which could be attributed to bacteriuria. However, obesity, low urine volumes, hypocitraturia, and hyperoxaluria suggest an underrecognized metabolic contribution to stone formation in this population.

Trends in renal calculus composition and 24-hour urine analyses in patients with neurologically derived musculoskeletal deficiencies.

PURPOSE: To better characterize metabolic stone risk in patients with neurologically derived musculoskeletal deficiencies (NDMD) by determining how patient characteristics relate to renal calculus composition and 24-hour urine parameters. MATERIALS AND METHODS: We performed a retrospective cohort study of adult patients with neurologically derived musculoskeletal deficiencies presenting to our multidisciplinary Kidney Stone Clinic. Patients with a diagnosis of NDMD, at least one 24-hour urine collection, and one chemical stone analysis were included in the analysis. Calculi were classified as primarily metabolic or elevated pH. We assessed in clinical factors, demographics, and urine metabolites for differences between patients who formed primarily metabolic or elevated pH stones. RESULTS: Over a 16-year period, 100 patients with NDMD and nephrolithiasis were identified and 41 met inclusion criteria. Thirty percent (12 / 41) of patients had purely metabolic calculi. Patients with metabolic calculi were significantly more likely to be obese (median body mass index 30.3kg / m2 versus 25.9kg / m2), void spontaneously (75% vs. 6.9%), and have low urine volumes (100% vs. 69%). Patients who formed elevated pH stones were more likely to have positive preoperative urine cultures with urease splitting organisms (58.6% vs. 16.7%) and be hyperoxaluric and hypocitraturic on 24-hour urine analysis (37mg / day and 265mg / day versus 29mg / day and 523mg / day). CONCLUSIONS: Among patients with NDMD, metabolic factors may play a more significant role in renal calculus formation than previously believed. There is still a high incidence of carbonate apatite calculi, which could be attributed to bacteriuria. However, obesity, low urine volumes, hypocitraturia, and hyperoxaluria suggest an underrecognized metabolic contribution to stone formation in this population.

Urinary biomarkers and occupational musculoskeletal disorders in the lower limbs.

BACKGROUND: Causation of occupational musculoskeletal disorders of the lower limbs (LLMSDs) may be multifactorial, including abnormal biological processes. Clinically validated biomarkers that reflect degradation of bone, cartilage and synovial tissue may be useful in identifying such processes in those presenting with LLMSD. AIMS: To investigate two urinary biomarkers as objective measures of occupational LLMSDs. METHODS: This cross-sectional study involved both working (n = 146) and case cohorts (n = 62); the latter were derived from general practitioner referrals or those occupationally re-deployed due to LLMSDs. Urine measurements of the c-telopeptides of collagens I and II and two validated quantitative questionnaires [SF12v2 and the Rheumatoid and Arthritis Outcome Score (RAOS) questionnaires] were the outcome measures. RESULTS: Urinary collagen II biomarker had largely the same significant discriminant power in distinguishing working from case cohorts, as several item scores within the RAOS questionnaire. Increased perceived pain within the RAOS questionnaire was statistically correlated to higher levels of the collagen II biomarker in all subjects and the combined working cohorts. However, both the pain score and the collagen II biomarker were significant but independent variables in distinguishing cases from non-cases. High levels of current or past sports activity involving the lower limbs were not significant explanatory variables of the collagen II levels. Collagen I biomarker showed no discriminant power between cases and working cohorts, suggesting that increased bone turnover was not a significant feature in the LLMSD cases. CONCLUSIONS: Urinary c-telopeptide of collagen II showed promise as a non-invasive, objective marker of abnormal biological process in LLMSDs.

The association of subjective stress, urinary catecholamine concentrations and PC game room use and musculoskeletal disorders of the upper limbs in young male Koreans.

The use of PCs can cause health problems, including musculoskeletal disorders (MSDs) of the upper limbs. This study was performed to investigate whether using PCs in PC game rooms may induce MSDs of the upper limbs. 284 young male Koreans were included. A self-administered, structured questionnaire was used to gather information about game room use, perceived subjective stress, and the symptoms related to MSDs. Urinary concentrations of epinephrine, norepinephrine, and dopamine were measured in spot urine. The symptom prevalence of MSDs of the upper limbs increased according to the increase of the duration of game room use. The intensity of perceived subjective stress showed a significant dose-response relationship with the frequency of MSDs symptoms in neck and shoulder areas. However, the urinary level of catecholamines was not significantly correlated with the symptom prevalence of MSDs in the upper limbs. These findings suggest that using PCs in game rooms produce physical stress on the upper limbs, strong enough to induce MSDs.