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СОВРЕМЕННЫЕ МЕТОДЫ ЛЕЧЕНИЯ КАМНЕЙ В ПОЧКАХ
Касимова Нихола Кадировна Ишанчаева Нилуфар Кадировна Рузи-ахунова Нилуфар Махмудовна
Андижанский государственный медицинский институт
Почечный камень или нефролитиаз - твердое кристаллическое вещество, образующееся в почках из веществ, содержащихся в моче. Он может быть размером с песчинку или большим, как жемчуг. Часто камни в почках покидают организм без помощи врача. Но иногда камень может не исчезнуть. Он может прилипать к мочевыводящим путям, блокировать отток мочи и вызывать сильную боль. В настоящее время разработаны современные методы лечения этого заболевания. Доступны лекарственные и хирургические методы лечения, которые развиваются из года в год. В этой статье мы обсудим современные методы лечения камней в почках.
Ключевые слова: Камни в почках, нефролитиаз, мочевыводящие пути, хирургия.
BUYRAK TOSH KASALLIGINI DAVOLASHNING ZAMONAVIY USULLARI
Buyrakdagi tosh yoki nefrolitiaz - bu siydikdagi moddalardan buyrakda hosil bo'ladigan qattiq kristall moddadir. U qum donasidek mayda yoki marvariddek yirik bo'lishi ham mumkin. Ko'pincha buyrak toshlari shifokor yordamisiz ham organizmdan chiqib ketadi. Ammo ba'zida tosh yo'qolmasligi ham mumkin. U siydik yo'liga yopishib qolishi, siydik oqimini to'sib qo'yishi va kuchli og'riq keltirib chiqarishi mumkin. Hozirgi kunda ushbu kasallikni davolashning zamonaviy usullari ishlab chiqilgan. Davolashning medikamentoz va jarroxlik usullari mavjud bo'lib, yil sayin rivojlanib bormoqda. Ushbu maqolada buyrak tosh kasalliklarini davolashning zamonaviy usullari haqida muhokama qilamiz.
Kalit so'zlar: Buyrak toshlari, nefrolitiaz, siydik yo'llari, jarrohlik.
MODERN METHODS OF TREATMENT OF KIDNEY STONES
A kidney stone or nephrolithiasis is a solid piece of material that forms in the kidney from substances in the urine. It may be as small as a grain of sand or as large as a pearl. Most kidney stones pass out of the body without help from a doctor. But sometimes a stone will not go away. It may get stuck in the urinary tract, block the flow of urine and cause great pain. At present, modern methods of treatment of this disease have been developed. There are medical and surgical methods of treatment, which are developing every year. In this article we will discuss modern methods of treatment of kidney stones.
Keywords: Kidney stone, nephrolithiasis, urinary tract, surgical.
Introduction: Kidney stones are small "pebbles" of salt and mineral in the urine. The most common symptom is severe pain. Most stones pass on their own, but medical procedures are used to remove some kidney stones. Kidney stones are hard pebble-like objects that can form inside your kidneys. They're made of minerals and salts. You might hear your doctor call them renal calculi, nephrolithiasis, or urolithiasis. Kidney stones are small usually between the size of a kernel of corn and a grain of salt. They can form when your body has too much of certain minerals, and at the same time doesn't have enough liquid. The stones can be brown or yellow, and smooth or rough. Risk factors for kidney stones include whites are more likely to develop kidney stones than African Americans or other races, men are more likely than women to
have stones, but the number of women with stones has gone up in the past ten years and this may be connected to the rise in obesity in women compared to men, as obesity is a known risk factor for kidney stones. Doctors break down kidney stones into types. Knowing which kind you have could affect the treatment you get. They include: Calcium stones: These are the most common ones. Even just eating some foods very high in oxalates, such as rhubarb, or taking unusually high levels of vitamin D, can boost your chances of getting this type. You could get this kind if you typically don't drink enough water or if you sweat a lot and don't replace the fluids you lose. Cystine stones: This is the least common type. This is the least common type and due to a genetic mutation. In this situation your kidneys have trouble reabsorbing a compound called cystine, which ends up in the urine at higher levels and causes stones to form. Struvite stones: Infections, especially in the urinary tract, can cause this kind of stone. Uric acid stones: Eating large amounts of animal proteins can lead to uric acid buildup in your urine. That can eventually form a stone either with or without calcium. Risk factors include gout, diabetes, and chronic diarrhea.
The doctor may want you to save the stone so it can be tested. Knowing what kind of stone it is may help prevent you from having another one. If your stone is bigger or you can't pass it, you might be in a fair amount of pain. In this case, the doctor can break up the stone in a couple of ways, so your body can eventually get rid of it.
Extracorporeal shock wave lithotripsy (ESWL) is one of the most used modalities in treatment of renal stones, but its effectiveness can be influenced by many factors related to the patient or the stone itself which may affect the success of stone disintegration. As for as some group scientists go said [1] that stone disease in the pediatric age group is known to have recurrence rates of approximately 30%-50% at later ages.[2] It is important to ensure complete stone clearance during the treatment of these children because residual stones may result in more frequent stone recurrences. When choosing the appropriate treatment approach for urolithiasis, the number, size, composition and location of stones, presence or degree of hydronephrosis, and anatomic factors such as ureteric anomalies, solitary kidney, pelviureteric junction obstruction, ureteral stricture, and morbid obesity should be noted [3]. Due to the short length of the ureter, and its greater flexibility and distensibility, it is known that stones fragmented with extracorporeal shockwave lithotripsy (SWL) pass more easily in children. SWL is easy to perform as an outpatient procedure with satisfactory stone-free (SF) rates. The main disadvantages of SWL are that it may require multiple sessions and each session would need anesthesia. Steinstrasse may form after SWL for large stones. In addition, it has a lower chance of success for cystine stones, lower pole stones, and stones larger than 2 cm [4,5]. With the development of the flexible endoscope and laser technology, retrograde intrarenal surgery (RIRS) may be applied to upper urinary tract stones with high success and low complication rates. After an initial experience in adult population, RIRS has also been successfully used for the pediatric age group. Park et al. reported that the application rate of SWL remained stable, while RIRS increased from 15% to 31% in the period between 2007 and 2014[5,6]. In the present study, we aimed to compare SWL and RIRS in pediatric patients with <2 cm upper urinary tract stones and to determine the predictive factors for success of both treatment modalities.
Extracorporeal shock wave lithotripsy (ESWL): This is the most common procedure for kidney stones in the United States. It uses shock waves, which can blast the stone into little pieces. Then, the smaller pieces can more easily be passed in your urine. The treatment takes about an hour, and you can usually go home about an hour later. It doesn't involve any surgical cuts, but there's still some pain. Your doctor will talk about your options with you: sedation, local anesthesia (you're given something to numb the pain but stay awake), and general anesthesia (you're not awake during the procedure). This procedure offers the patient
the chance to have the stone fragmented inside the urinary tract without cutting or internal instruments. The technology focuses pressure waves from outside the body to the stone location and with a series of pressure waves delivered over a 1-hour treatment and with the help of general anesthesia, this procedure can break stones small enough to be able to be passed out of the urinary tract spontaneously. Stones in the kidney and ureter can be treated with this technology. Although many stone patients can be offered SWL, not all stones can be treated with SWL. Stones that are made of cystine and some types of calcium oxalate stones or if larger than half an inch maybe better treated with other technology. Patients may see blood in their urine after the treatment while passing the fragments and some patients may have pain passing fragments.
Elawady, Mahmoud and Samir gave own conclusions in own article [7]: ESWL is considered an important treatment option in the field of urology. It has the main benefits of high safety and low invasiveness nature. However, multiple studies have showed that percutaneous nephrolithotomy (PNL) and URS have higher stone free rate than ESWL. [8] So, it is necessary to determine the potential predictors for ESWL outcome and to define the ideal treatment option for each patient. [9] Hameed et al. [10] reported that successful fragmentation using ESWL was decreased in stones with HU >1350, which required application of more shock waves. El-Assmy et al. [11] used the Hounsfield value of the stones to predict stone composition and density, and the fragmentation success using ESWL, and selected HU >1000 as their cut off value. Also, Foda et al. [12] demonstrated that stone disintegration failed if the stone density was > 934 HU and Massoud et al. [13] reported that in patients with > 956.5 HU, ESWL should not be considered or offered to patients as a first treatment. In 2018 Waqas et al. [14] in a study on 203 patients reported that patients having stone density of less than 500HU were more likely to have stone clearance (93.8%), while patients having values greater than 1000HU were less likely to experience successful outcomes (24.5%). In our study, we found similar results the mean±SD of HU was 808.74±227.84 and the cutoff point for successful ESWL was <975. According to a study conducted by Park et al. In 2012 on 43 patients, 33 patients were stone free versus 10 patients had residual stones. The mean SSD was 7.825±1.215cm for the stone free group versus 9.203±1.451cm for the residual stone group (p<0.01). They described SSD as the only significant factor for prediction of ESWL success and they attributed that to loss of shock waves energy during penetration through excess body fat with increased SSD. Also, Badran et al. suggested that shock waves lose their energy by 10% to 20% for every 6-cm penetration and Perks et al. [15] defined 90mm as the threshold value for SSD beyond which the success rate decreases. While, Waqas et al.1 reported that SSD of 100mm as a cut off value with success rate of 71% in patients having SSD less than 100mm. We found similar results in our study, with the mean success value of SSD is 9.28±2.00 range from 6 to 14 cm while cutoff value of SSD was 86mm, with success rate of 70% in patients having SSD less than 86mm. Also, we noted that HU was better than SSD in predicting success of ESWL but without statistical significance. Pareek et al., [16] found that BMI was a significant predictor of success. Conversely, in our study, BMI failed to predict successful ESWL outcome, while SSD remained a significant predictor and this agrees with Ng et al. [17] and Choi et al. [18] who found that BMI was not a significant predictor of ESWL failure. They suggested that the effect of BMI is probably related to the distance of the stone from the skin, which reflects the shock wave path in the body. Waqas et al.1 noted that there was a correlation between the stone burden (stone size, surface area, and volume) and the success rate but this wasn't significant in the multivariate analysis. Similarly, Pareek et al. [16] showed that there was no significant difference between SF and RS groups as regard stone size. This agreed with our study, we have found that the difference in stone size was statistically insignificant between groups.
This can be explained by the homogeneity of stone size in our study population leading to a type I error. In contrast, Bandi et al. [19] concluded that stone volume was the best predictor of stone free status. The main disadvantages of our study are mainly the wide range of stone size 10-20mm, also we did not consider some factors like (stone volume, surface area, and Hounsfield density), pain, procedure complications and patient compliance. So, further multicenter studies on a larger number of patients are needed to validate our results. ESWL is one of the most used modalities in management of renal stones but its effectiveness is influenced with variable factors. So, better patient selection is paramount to improve ESWL outcome. We found that HU and SSD are the most powerful predictors of ESWL outcome and should be used for proper patient selection and planning the treatment of renal stones.
Ureteroscopy: This procedure treats stones in your kidneys and ureters. The doctor uses a thin, flexible scope to find and remove stones. They won't make any cuts in your skin, but you will be asleep during this procedure. The doctor will pass the scope through your bladder and ureter into your kidney. They'll use a small basket to remove small stones. If the stones are larger, the doctor will pass a laser through the scope to break them up. Most people go home the same day. The development of small fiberoptic telescopes both semi-rigid and flexible can now allow your urologist the ability to pass this device into the lower urinary tract through the urethra without an incision. He/she can pass the scope through the bladder and into the ureter and all the way into the kidney if needed, to be able to treat stones in any location. Small stones can be removed with the use of a tiny wire basket. Larger stones can be fragmented with the use of a holmium laser that creates tiny shock waves that break the stone into small fragments that can be passed out of the ureter. This procedure allows the urologist to visualize the stone during the treatment for safe fragmentation. Once the stone has been removed or fragmented, the urologist may place a temporary stent in the ureter. A stent is a small soft silicone tube (looks like a piece of green spaghetti) that helps the urine drain from the kidney into the bladder. This stent is completely within the body and does not require an external bag to collect urine. If a stent is placed, it will need to be removed by the urologist in 3 to 10 days. It is very important that the stent is removed as it can cause complications if left in place for an extended period of time (months). As for as some group scientists go said [20] that RIRS has gained increased popularity among the urological community. This is certainly because of the continuous technological advancements, which have continuously improved the RIRS performance but also to the perception of ease and safety of this procedure when compared with the other available treatment modalities, particularly percutaneous nephrolitotomy. Indeed, the reported advances in RIRS technique have significantly improved the outcomes of this procedure but care should be taken not to underestimate its potential challenges.
Another group of scientists is of the opinions that, Minimal invasive surgery technique is continuously developing, establishing new approaches for different pathologies and completing the idea of personalized treatment with significant benefits. Nephrolithiasis is one of the most frequent diseases in a urology department, and several methods are nowadays available for sustaining rapid results with minimal risks for the diagnosed patients. In particular cases of abnormal anatomy, associated lithiasis can be a difficult challenge, and proper surgical indications may be confusing. An ectopic pelvic kidney is an anomalous condition that originates from embryological development [21]. Reported incidence for this variety of pathology was estimated to be 1 to 220-3000 cases [22]. Renal drainage can be severely affected, and as a direct consequence, urolithiasis increases the risk of further complications [23, 24]. While stone access difficulties in an abnormal urinary tract were described in several studies, endourological treatment represented a challenging situation for urologists [22]. Shock wave lithotripsy (SWL) and percutaneous nephrolithotomy (PCNL) are
considered good alternatives but often raise technical difficulties, and success defined by the stone-free rate is frequently lower than those performed on patients with normal anatomy [25, 26]. Other approaches such as robotic, laparoscopic pyelolithotomy, or laparoscopic-assisted PCNL were also described during past years. Nowadays, retrograde intrarenal surgery gained more attention in treating stones, usually smaller than 2 cm according to the actual guidelines, and offers an appropriate alternative due to low complications and a high percentage of stone-free rate [27]. Over the years, much progress has been made which considerably improved surgical aspects. Some of these findings, like smaller caliber, increased deflection, more powerful laser sources, and high-quality cameras, made flexible ureteroscopy a solid option in accessing the pyelocaliceal system [28]. The most recent achievement in retrograde intrarenal surgery, the development of single-use ureteroscopes, represents a significant step in urology. Besides the technical advantages, which already demonstrated single-use scope's superiority compared to reusable ones, this complete sterile procedure definitely decreases the risk of hospital-associated infections. Some studies also sustain the idea of cost-effectiveness in favor of disposable devices [29]. Actual trends suggest personalized treatment for every patient according to the associated pathology following the idea of fewer complications, improved results, less hospital stay, and rapid social reintegration. Since flexible ureteroscopes already demonstrated their superiority compared to PCNL, SWL or laparoscopy even when accessing an abnormal urinary tract, this study aims to evaluate the advantages expressed in the safety and efficacy of single-use devices in challenging situations such as an ectopic pelvic kidney. Single-use flexible ureteroscopy represents a good alternative associated with a high stone-free rate and low complications when treating stones in cases with genetic malformations like an ectopic pelvic kidney. When dealing with large calculi greater than 2 cm, more than one session may be necessary to achieve a higher stone-free rate. Disposable ureteroscopes severely decrease the risk of newly appeared defections during the intervention and almost annihilate the risk of crossed infections compared to reusable ones and represent a significant step into developing a personalized treatment for each patient.
Percutaneous nephrolithotomy: Another way doctors can get rid of a kidney stone is to cut a small hole in your back and through your kidney in order to remove the stone. If this procedure is done, you could have to stay in the hospital for several days. This procedure is recommended when stones in the kidney are too large to treat with SWL or ureteroscopy. PNL involves making a half incision (cut) in the side, after a needle is advanced to the inside of the kidney, a balloon is used to gently dilate an opening large enough for a rigid scope (nephroscope) to be passed from the back into the hollow center part of the kidney where the stone is located. An instrument passed through the nephroscope breaks up the stone and suctions out the pieces. Grasping forceps can also be used to remove fragments. This ability to fragment and remove fragments from the kidney makes PNL the best option for large stones. After the stone removal, either an internal stent or external drainage tube is needed to help the kidney recover from the stone removal. Patients usually remain in the hospital at least over night for this operation. Follow-up imaging will determine if all stones have been removed prior to removal of the stent or nephrostomy tube. Patients can usually return to normal activity after about 1-2 weeks.
Today, PCNL is not standardized in terms of technical considerations such as access tract size and devices used for stone disintegration. Standard PCNL enables the use of probes that make it possible for fragments to be both disintegrated and removed by suction through the same probe. Older devices that rely purely on ballistic or ultrasonic techniques are still viable and have proven their efficacy and safety over many years. New technological advances including single-probe dual-modality lithotripters using a combination of ultrasonic and
ballistic techniques are promising, and seem to be more effective than single-energy probes. Mini PCNL requires smaller probes for lithotripsy, and larger fragments cannot be extracted through the probe. However, small fragments resulting from laser lithotripsy can be effectively evacuated using the vacuum cleaner effect [30, 31]. New developments such as the use of laser lithotripsy in combination with suction devices in mini PCNL appear to be safe and effective, and may even further increase the efficacy and safety of mini PCNL. Moreover, laser probes are flexible and can be used in flexible endoscopic devices. There is limited quality evidence comparing standard and mini PCNL, although research has indicated that mini PCNL is associated with fewer bleeding complications and shorter hospital admissions [32]. However, a drawback of mini PCNL is that it apparently requires longer OR time [32]. On the other hand, the use of laser lithotripsy combined with suction may be a promising alternative that can potentially improve mini PCNL performance by shortening OR times [33, 34]. In that context, using supine positioning of patients during PCNL is a good alternative, especially in complex renal stone situations that require a combined approach (i.e., ECIRS). However, there is no evidence that one method is better than the other, such as standard PCNL with ballistic and/or ultrasonic disintegration or mini PCNL with laser disintegration. However, the evolution of different techniques has increased the possibilities of a personalized approach, in other words, the right method for the right patient.
Percutaneous nephrolithotomy (PCNL) was first described in 1976 by Fernstrom and Johansson as an operative technique for the removal of kidney stones through a percutaneous nephrostomy tract [35]. The approach was further developed in subsequent years, as illustrated by a case series published by Alken in 1981, which showed promising results in treatment of stones when using direct percutaneous ultrasound lithotripsy and stone extraction [36]. Further improvements in PCNL over the last decades have led to this method becoming one of the cornerstones in the treatment of large kidney stones, alongside shock wave lithotripsy (SWL) and retrograde intrarenal surgery (RIRS). In the EAU guidelines, PCNL is the standard procedure for large renal calculi (> 2 cm). The choice of endoscope, lithotripsy technique, and access tract size is made at the discretion of the surgeon and is not standardized [37]. The evolution of smaller tract sizes with the mini PCNL procedure and the effect of that approach on complication rates and stone-free rates (SFRs) are still not clear, and there is a scarcity of randomized controlled trials and high-quality research in this area. To evaluate the balance between existing evidence, expert opinions, and the safety and efficacy of new technological improvements in lithotripsy in PCNL, key opinion leaders in the field were invited to evaluate and discuss the available evidence at a 2-day meeting entitled "Consultation on Kidney Stones: Aspects of Intracorporeal Lithotripsy "held in Copenhagen, Denmark, in September 2019. The experts were assigned different topics and prepared their presentations through scoping reviews achieved by scanning the literature using PubMed, EMBASE, and Web of Science. The first day of the meeting was open only to the experts, who first presented their topics for each other, after which the presentations were discussed within the group and were subsequently adjusted if necessary. The second day was open to a global audience, with all the experts giving their presentations, and this was followed by free discussions.
Laparoscopic, robotic, open surgery. These procedures are rarely used to removes stones. They are used only if all other less invasive procedures fail. They require a hospital stay and have a longer recovery period. All three of the treatment options require anesthesia for the treatment. In most cases general anesthesia is used at our treatment center. This allows safer and more accurate treatment for most patients. When SWL or PNL is planned, patients are asked to stay off medications that may increase the risk of bleeding for 10 to 14 days. (Aspirin, non-steroidal meds like Motrin, Advil, or Aleve) and some over the counter
meds like fish oil, vitamin E, gingko, and St John's wort. If patients need to remain on blood thinners for medical reasons, then ureteroscopy and laser lithotripsy may be the best choice. SWL is not an option for pregnant patients.
Conclusion: In conclusion, In this article we discussed modern methods of treatment of kidney stones. We have analyzed the opinions and conclusions of several scientists on this topic. We believe that this article can be an impetus for further in-depth research.
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