Pattern of urolithiasis in a general hospital a prospective study

Judging from the abundance of papers published in the medical journals there appears to be a global increase in the incidence of urolithiasis. Urinary excretion of various stone-forming salts in a 24-hour urine specimen is the mainstay of the metabolic workup done in stone-formers. According to the findings patients have been classified into neat categories depending on whether they were hypercalciuric, hyperuriocosuric, etc. As a group their excretion of calcium, oxalate, and urate was not different from the controls. However, they excreted significantly more phosphate and had lower 24-hour urine volumes than the controls.     

Urinary NAG in children with urolithiasis,nephrocalcinosis, or risk of urolithiasis

A crucial role for cell-crystal interactions in the development of urolithiasis (UL) and nephrocalcinosis (NC) was previously observed in experiments with different cell lines mimicking renal epithelial cells. It was found that such cell-crystal interactions lead to tubular damage and/or or dysfunction. To find further proof for these observations, we measured the urinary N-acetyl--d-glucosaminidase (NAG) excretion, a marker of proximal tubular damage, in children with UL or NC and in children with an increased risk of UL. We enrolled 142 children aged 4–16 years (mean 9.67±3.40 years), with 50 children having UL, 30 children with a history of UL (ULH), 20 patients with NC, 34 children with secondary hyperoxaluria (HyOx), and 8 children with idiopathic hypercalciuria (HC). Normal urinary NAG/Cr values were determined in a group of 70 healthy children aged 4–16 years (mean 10.06±3.97 years). The urinary NAG activity was measured using a colorimetric method and the results were expressed as molar creatinine (Cr) ratios. The highest median NAG/Cr ratios were found in children with UL plus hematuria (0.72 U/mmol) and in children with UL (0.67 U/mmol) or NC (0.48 U/mmol), which were all significantly higher than those in controls (0.28 U/mmol, P<0.001 and P<0.05). The NAG/Cr ratios were increased above the upper normal reference interval of 0.63 U/mmol (95th percentile) in 28 of 50 (56%) children with UL and in 9 of 20 (45%) children with NC. Although the ULH group also had significantly higher median NAG/Cr ratios (0.36 U/mmol) compared with controls, the NAG/Cr ratio was only elevated in 4 of 30 (13%) patients. NAG values in children with secondary HyOx or HC were not different from controls. No correlation was found between the NAG/Cr ratios and the urinary excretion of oxalate or calcium. In conclusion, UL or NC may result in proximal tubular injury, which is rather the consequence of disease activity and of the mechanical influence of calculi, than of the metabolic background. The mechanism of cell damage in these conditions however, seems to be complex. Neither HyOx nor HC alone were sufficient to induce severe tubular damage expressed as an increase in NAG excretion in our patients.     

The first epidemiology study of urolithiasis in New Brunswick

IntroductionUnderstanding the composition of a kidney stone is crucial in leading to proper treatment and preventing reoccurring urolithiasis. This study aimed to investigate the prevalence of urolithiasis in the province of New Brunswick (NB), Canada.MethodsA total of 3828 kidney stone analysis reports from October 1, 2016 to September 30, 2019, were reviewed from laboratory information systems. Among them, 3311 were identified as new cases. Stone compositions were analyzed by the Fourier transform infrared spectrometry. Incident rates were compared using Chi-squared analysis of different age, sex, and regional health authority (RHA) zones.ResultsThe prevalence of urolithiasis in NB was 147.8 per 100 000 person-years. Males had a significantly higher (X²=254, p<0.001) incident rate of 189 (95% confidence interval [CI] 182–198) than females (107 [95% CI 102–114]) per 100 000 person-years. Zone 1 had significantly higher (245 per 100 000 person-years, p<0.001) prevalence compared to other RHA zones. Age group over 65 years had the highest incidence rate of 253 per 100 00 person-years of all groups. The predominant kidney stone types in NB were calcium oxalate monohydrate (60.68%) and calcium oxalate dihydrate (11.58%). Those patients aged 0–18 years had a high percentage of struvite (4.32%) vs. the provincial average (2.19%) (p<0.001).ConclusionsThe prevalence of NB’s urolithiasis is slightly higher than that of Ontario. Since both zones 1.1 and 1.2 have significantly high prevalence and are situated in the Moncton area (combined zone 1), it may suggest that geographical factors play a role in the prevalence of urolithiasis in NB.     

代谢组学与泌尿系结石相关研究新进展

泌尿系结石是泌尿系统常见的非肿瘤疾病,其逐年升高的患病率和发病率给社会带来沉重的医疗负担,而目前泌尿系结石的确切病因尚未明确,早期诊断、预防及术后随访等均缺乏较简便、易行的方法。代谢组学是继基因组学、蛋白组学和转录组学之后的新兴组学,代谢组学通过检测生物体在受到外源刺激或基因修饰后机体内代谢物质的变化,从而探索整个生物体的代谢机制变化。利用代谢组学的方法研究泌尿系结石,有望为泌尿系结石病因、早期诊断、预防及术后随访提供新的思路。本文就代谢组学相关概念和研究方法及其在泌尿系结石方面的基础及临床研究最新进展作一综述。     

Pattern of calcium metabolism in normo- and hypercalciuric patients with calcium urolithiasis in Saudi Arabia

Urinary calcium excretion was measured in 100 consecutive normocalcemic patients with calcium urolithiasis and 12 Saudi Arabian controls while the patients and the controls were eating their usual diet of unknown calcium content. Only 16 patients were hypercalciuric using the definition of twenty-four-hour urinary calcium of more than 300 mg for males and more than 250 mg for females, and one of these patients was subsequently found to have hyperparathyroidism. The twenty-four-hour urine calcium was less than 200 mg in 60 per cent of male patients and in all the male controls. Since the dietary intake of calcium during the twenty-four-hour urinary collection was unknown, a 1,000-mg calcium loading test was performed in an attempt to differentiate various patterns of abnormal calcium excretion. Of the twenty-four-hour normocalciuric patients 10 (18%) had "absorptive hypercalciuria" and 16 patients (29%) demonstrated a "renal hypercalciuria" pattern. Thirty-nine patients (57%) and all 12 controls had normocalciuria before and after calcium loading.     

Two New York City hospitals' surgical response to the September 11, 2001, terrorist attack in New York City

BACKGROUND: We describe the surgical response of two affiliated hospitals during the day of, and week following, the September 11th, 2001 terrorist attack at the World Trade Center in New York City. The city of New York has 18 state designated regional trauma centers that receive major trauma victims. The southern half of Manhattan is served by a burn center, two regional trauma centers, and a community hospital that is an affiliate of one of the regional trauma centers. This report accounts for the surgical response by a regional trauma center (Hospital A, located 2.5 miles from the World Trade Center) and its affiliate hospital (Hospital B, located 5 city blocks from the World Trade Center) on September 11th when two commercial jets crashed into the Twin Towers at the World Trade Center mall. METHODS: Hospital A maintained a concurrent log of patients received during the first 5 hours, the first day, and the first week after the disaster which was kept by the Surgical Triage Officer. The trauma registry completed and verified this data by September 18th. Hospital B collected its data by hand counting and verification by chart review. Both hospitals, A and B, had established disaster plans that were implemented. RESULTS: Nine hundred eleven patients were received by two affiliated hospitals from the World Trade Center attack. Seven hundred seventy six patients (85%) were walking wounded, sustaining mild inhalation and eye irritant injuries. One hundred thirty five (15%) were admitted with 18 (13%) of these undergoing surgery. Twenty two of the 23 transfers were from the community hospital to specialized orthopedic or burn centers. Of the 109 patients admitted to Hospital A, 30 were to the surgical service. The mean ISS score of these patients was 12. There were 4 deaths (within minutes of arrival at the hospital) and 6 delayed deaths (day 1-14). Excluding walking wounded and DOAs, the critical mortality rate was 37.5% overall. CONCLUSION: The September 11th, 2001, terrorist attack in New York City, involving two commercial airliners crashing into the World Trade Center, led to 911 patients received at two affiliated hospitals in lower Manhattan. One hospital is a regional trauma center and one was an affiliate community hospital. Eighty five percent of the patients received were walking wounded. Of the rest, 13% underwent surgical procedures with an overall critical mortality rate of 37.5%.