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71.

Aim

Renal tubular dysfunction (RTD) causing obligate production of hypoosmolar urine in boys with posterior urethral valves (PUVs) has been described. It is not known how clinically significant this is. We hypothesize that a feedback loop is present in many PUV boys who suffer deterioration of their lower urinary tract (LUT). RTD results in hypoosmolar urine, obligate polyuria, and bladder stretch-injury. The increasing back-pressure worsens RTD, thus exacerbating the injury. Coexisting renal dysplasia and acquired renal scarring exacerbate this.We compared the concentrating ability (random clinic urine osmolality) of PUV boys who had no LUT deterioration to those who required intervention, examining the confounding effect of renal impairment with a subgroup analysis comparing those with plasma creatinine ≤ 80 μmol/l.

Methods

A retrospective review of our PUV database was performed. Age, intervention, and highest recorded random clinic urine osmolality (> 1 year) with concurrent plasma creatinine were recorded (normal urine osmolality 500–850 mOsm/kg). Data are given as median values, analyzed by Mann–Whitney u-test, with P < 0.05 deemed significant.

Main results

Urine osmolality was available in 77 boys with PUV out of 125 in our series. Of these, 34 required subsequent intervention (e.g., Mitrofanoff procedure, bladder augmentation). Age at testing trended towards being higher in the intervention group [7.9 (4.3–10.9) years vs. nonintervention 6.3 (4–8.4); P = 0.06]. Urine osmolality was significantly reduced in the intervention group [411(293–547) vs. 631 (441–805) mOsm/kg; P < 0.001]. Subgroup analysis comparing only those with creatinine ≤ 80 μmol/l was respectively 451 (322–567) mOsm/kg (n = 22) vs. 645 (469–810) mOsm/kg (n = 40), P < 0.01.

Conclusion

This study confirms that hypoosmolar urine is highly associated with progression of LUT dysfunction, requiring intervention. Even boys with normal creatinine values have a greater risk of LUT deterioration if they have a RTD and produce hypoosmolar urine.

Level of evidence

IV (retrospective service development project).  相似文献   
72.

Background/purpose

Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the standard surgical treatment for ulcerative colitis (UC). The purpose of the current study was to determine the outcome of very young patients (≤10 years of age) with UC undergoing IPAA.

Methods

Between 1978 and 2002, 13 patients 10 years of age or younger underwent IPAA for management of UC at the authors’ institution. Charts were reviewed for patient characteristics, and a standardized telephone interview was performed.

Results

Average age at diagnosis was 4.0 years (range, 1.0 to 8.4 years), and patients underwent IPAA at a mean of 6.8 years (range, 3.7 to 10.8 years). Pancolitis was present in 100%. The mean follow-up was 9.1 years (1.0 to 16.1 years), the average number of stools per day was 5 (3 to 8). All patients are continent while awake. Pouchitis was documented in 9 patients (75%). All patients or their parents rated the outcome of their procedures as “excellent.”

Conclusions

When compared with older children, very young patients with UC tend to have more frequent total colonic involvement and a greater frequency of pouchitis after IPAA. The functional outcome and patient/family satisfaction with the procedure endorse IPAA as an attractive procedure even in the very young population with UC.  相似文献   
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Current methods using a single PET scan to detect voxel-level transient dopamine release—using F-test (significance) and cluster size thresholding—have limited detection sensitivity for clusters of release small in size and/or having low release levels. Specifically, simulations show that voxels with release near the peripheries of such clusters are often rejected—becoming false negatives and ultimately distorting the F-distribution of rejected voxels. We suggest a Monte Carlo method that incorporates these two observations into a cost function, allowing erroneously rejected voxels to be accepted under specified criteria. In simulations, the proposed method improves detection sensitivity by up to 50% while preserving the cluster size threshold, or up to 180% when optimizing for sensitivity. A further parametric-based voxelwise thresholding is then suggested to better estimate the release dynamics in detected clusters. We apply the Monte Carlo method to a pilot scan from a human gambling study, where additional parametrically unique clusters are detected as compared to the current best methods—results consistent with our simulations.  相似文献   
75.
Deletion 9p and sex reversal.   总被引:9,自引:2,他引:9       下载免费PDF全文
We report a case of a female infant with a de novo deletion of the short arm of chromosome 9, sex reversal, and an apparently intact SRY gene. Sex reversal has been reported in a number of subjects with a normal Y chromosome and a deletion of the terminal segment of the short arm of chromosome 9. The factors controlling early development of the male testes are unknown. There are likely to be many genes involved and we present additional evidence that one of these is situated on the end of the short arm of chromosome 9.  相似文献   
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This report documents retrospectively a case of Posterior Interosseous Neuropathy (PIN) occurring in an elite baseball pitcher experiencing a deep ache in the radial aspect of the forearm and altered sensation in the dorsum of the hand on the throwing arm during his pitching motion. The initial clinical goal was to control for inflammation to the nerve and muscle with active rest, microcurrent therapy, low-level laser therapy, and cessation of throwing. Minimizing mechanosensitivity at the common extensor region of the right elbow and PIN, was achieved by employing the use of myofascial release and augmented soft tissue mobilization techniques. Neurodynamic mobilization technique was also administered to improve neural function. Implementation of a sport specific protocol for the purposes of maintaining throwing mechanics and overall conditioning was utilized. Successful resolution of symptomatology and return to pre-injury status was achieved in 5 weeks. A review of literature and an evidence-based discussion for the differential diagnoses, clinical examination, diagnosis, management and rehabilitation of PIN is presented.  相似文献   
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