The main reason for this is that, compared with CT, renal ultrasonography more often fails to detect small stones (especially ureteral stones) and other serious disorders that could be causing the symptoms.On the contrary, a 2014 study suggested that ultrasonography should be used as the initial diagnostic imaging test, with further imaging studies be performed at the discretion of the physician on the basis of clinical judgment, and using ultrasonography rather than CT as an initial diagnostic test results in less radiation exposure and equally good outcome. Laboratory examination
Laboratory investigations typically carried out include
microscopic examination of the urine, which may show red blood cells, bacteria, leukocytes, urinary casts, and crystals;
urine culture to identify any infecting organisms present in the urinary tract and sensitivity to determine the susceptibility of these organisms to specific antibiotics;
complete blood count, looking for neutrophilia (increased neutrophil granulocyte count) suggestive of bacterial infection, as seen in the setting of struvite stones;
renal function tests to look for abnormally high blood calcium levels (hypercalcemia);
24 hour urine collection to measure total daily urinary volume, magnesium, sodium, uric acid, calcium, citrate, oxalate, and phosphate;
collection of stones (by urinating through a StoneScreen kidney stone collection cup or a simple tea strainer) is useful. Chemical analysis of collected stones can establish their composition, which in turn can help to guide future preventive and therapeutic management. Composition
Calcium-containing stones
By far, the most common type of kidney stones worldwide contains calcium.
Pharmacology
Mechanism of action
Reslizumab is an interleukin-5 antagonist monoclonal antibody. IL-5 is the major cytokine responsible for the growth and differentiation, recruitment, activation, and survival of eosinophils. Eosinophils play a role in the mediation of inflammation in the airways. Eosinophilic asthma is a phenotype of asthma that is characterized by the higher than normal presence of eosinophils in the lung and sputum. It has been shown that the numbers of eosinophils in the blood and bronchial fluid can correlate with asthma severity. Reslizumab binds to IL-5 with a dissociation constant of 81 pM and inhibiting IL-5 signaling, which reduces the production and survival of eosinophils. However, the mechanism of reslizumab action in asthma has not been definitively established. Pharmacodynamics
Reductions in blood eosinophil counts were observed following the first dose of reslizumab and maintained through 52 weeks of treatment. In phase III clinical trials, mean eosinophil counts were 696 cells/µL (n=245) and 624 cells/µL (n=244) at baseline. Following 52 weeks of reslizumab treatment, eosinophil cells were counted and were reported to be 55 cells/µL (92% reduction, n=212) and 496 cells/µL (21% reduction, n=212) for the reslizumab and placebo treatment groups, respectively. Furthermore, eosinophil count returned towards baseline in those reslizumab-treated patients who completed a follow-up assessment (n=35, 480 cells/µL), approximately 120 days after the last dose of reslizumab. Therefore, reductions of blood eosinophils were related to reslizumab serum levels. Pharmacokinetics
The pharmacokinetic characteristics of reslizumab are similar across the children and adults. Peak serum concentrations are observed at the end of infusion and declines in a biphasic manner.