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The deep inferior epigastric perforator (DIEP) flap has been widely used for autologous breast reconstruction after mastectomy. In the conventional surgical method, a long incision is needed at the anterior fascia of the rectus abdominis muscle to obtain sufficient pedicle length; this may increase the risk of incisional hernia. To shorten the incision, several trials have investigated the use of endoscopic/robotic devices for pedicle harvest; however, making multiple additional incisions for port insertion and operating in the intraperitoneal field were inevitable. Here, we describe the first case, in which a DIEP free flap was successfully made using the da Vinci SP model. Our findings can help surgeons perform operations in smaller fields with a single port in the extraperitoneal space. Moreover, this method is expected to lead to fewer donor-related complications and faster healing.
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Parathyroid carcinoma is very rare malignant neoplasm, accounting for less than 0.005% of all cancers. Most parathyroid carcinoma is a functioning tumor that causes hyperparathyroidism, leading to hypercalcemia. We report a parathyroid carcinoma case that was suspicious for spontaneous infarction of cancer, leading to resolution of hypercalcemia. A 29-year-old male visited our hospital presenting with right neck swelling and pain. He has been experiencing frequent urolithiasis for four years but laboratory tests showed normal serum calcium level. Right vocal cord paresis was identified with laryngoscopy. Ultrasonography revealed a 3.7 × 3.5 cm mass in the right thyroid containing a focal cystic portion. Computed tomography confirmed the presence of a low-density right thyroid mass. Right thyroid lobectomy was performed and pathological evaluation revealed parathyroid carcinoma with central necrosis. We report this very rare case with a literature review.
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Background/Aims@#Hypertension is considered a risk factor in immunoglobulin A nephropathy (IgAN). However, after IgAN diagnosis, the relationship between early blood pressure control and renal prognosis remains unclear. This study aimed to analyze the association between the prognosis of IgAN patients and a controlled status of hypertension within the first year of IgAN diagnosis. @*Methods@#We retrospectively analyzed 2,945 patients diagnosed with IgAN by renal biopsy. The patients were divided into ‘normal,’ ‘new-onset,’ ‘well-controlled,’ and ‘poorly-controlled’ groups using blood pressure data from two consecutive measurements performed within a year. The Kaplan-Meier survival analysis and Cox proportional-hazards regression model were used to survey the independent association between recovery from hypertension and the risk of IgAN progression. The primary endpoint was IgAN progression defined as the initiation of dialysis or kidney transplantation. @*Results@#Before IgAN diagnosis, 1,239 patients (42.1%) had been diagnosed with hypertension. In the fully adjusted Cox proportional-hazards models, the risk of IgAN progression increased by approximately 1.7-fold for the prevalence of hypertension. In the subgroup analyses, the ‘well-controlled’ group showed a statistically significant risk of IgAN progression (hazard ratio [HR], 3.19; 95% confidence interval [CI], 1.103 to 9.245; p = 0.032). Moreover, the ‘new-onset’ and ‘poorly-controlled’ groups had an increased risk of IgAN progression compared to the ‘normal’ group (HR, 2.58; 95% CI, 1.016 to 6.545; p = 0.046 and HR, 3.85;95% CI, 1.541 to 9.603; p = 0.004, respectively). @*Conclusions@#Although hypertension was well-controlled in the first year after IgAN diagnosis, it remained a risk factor for IgAN progression.
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Transoral thyroidectomy using the vestibular approach has achieved excellent cosmetic outcomes without leaving any visible scars. However, concerns have been raised on how to prevent complications, such as skin perforation and anterior jugular vein injury, especially in the learning period. This is because working space is generally created via blind and blunt dissection using a blunt dilator through small vestibular incisions unfamiliar to beginners. Herein, we explain an intraoperative real-time ultrasound technique employed in transoral thyroidectomy to safely elevate a skin flap while avoiding any damage to the flap and anterior jugular vein in the learning period.
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Background@#Data on liver cirrhosis (LC) patients undergoing continuous renal replacement therapy (CRRT) are lacking despite the dismal prognosis. We therefore evaluated clinical characteristics and predictive factors related to mortality in LC patients undergoing CRRT. @*Methods@#We performed a retrospective observational study at two tertiary hospitals in Korea. A total of 229 LC patients who underwent CRRT were analyzed. Patients were classified into survivor and non-survivor groups. We used multivariable Cox regression analyses to identify factors predictive of in-hospital mortality. @*Results@#During a median follow-up of 5 days (interquartile range, 1–19 days), in-hospital mortality rate was 66.4%. In multivariable analysis, the Acute Physiology and Chronic Health Evaluation II (APACHE II) score (hazard ratio [HR], 1.03; 95% confidence interval [CI], 1.01–1.06; p = 0.02), Model for End-Stage Liver Disease (MELD) score (HR, 1.08; 95% CI, 1.04–1.11; p 35 mL/kg/hr (HR, 3.13; 95% CI, 1.62–6.05; p = 0.001). Subgroup analysis revealed that a CRRT delivered dose < 25 mL/kg/hr was a significant risk factor for in-hospital mortality among LC patients with a MELD score ≥ 30. @*Conclusion@#High APACHE II score, high MELD score, and low delivered CRRT dose were significant risk factors for in-hospital mortality. CRRT delivered dose impacted mortality significantly, especially in patients with a MELD score ≥ 30.
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Robot-assisted surgery is evolving to incorporate a higher number of minimally invasive techniques. There is a growing interest in robotic breast reconstruction that uses autologous tissue. Since a traditional latissimus dorsi (LD) flap leads to a long donor scar, which can be an unpleasant burden to patients, there have been many attempts to decrease the scar length using minimally invasive approaches. This study presents the case of a patient who underwent a robot-assisted nipple-sparing mastectomy followed by immediate breast reconstruction with an LD flap using a single-port robotic surgery system. With the assistance of a single-port robot, a simple docking process using a short and less visible incision is possible. Compared to multiport surgery systems, single-port robots can reduce the possibility of collision between robotic arms and provide a clear view of the medial border of the LD where the curvature of the back restricts the visual field. We recommend the use of single-port robots as a minimally invasive approach for harvesting LD flaps.
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Background@#In prosthesis-based breast reconstruction patients, the drain tends to be kept in place longer than in patients who undergo only mastectomy. Postoperative arm exercise also increases the drainage volume. However, to preserve shoulder function, early exercise is recommended. In this study, we investigated the effect of early exercise on the total drainage volume and drain duration in these patients. @*Methods@#We designed a prospective randomized trial involving 56 patients who underwent immediate breast reconstruction following mastectomy using tissue expanders. In each group, the patients were randomized either to perform early arm exercises using specific shoulder movement guidelines 2 days after surgery or to restrict arm movement above the shoulder height until drain removal. The drain duration and the total amount of drainage were the primary endpoints. @*Results@#There were no significant differences in age, height, weight, body mass index, or mastectomy specimen weight between the two groups. The total amount of drainage was 1,497 mL in the early exercise group and 1,336 mL in the exercise restriction group. The duration until complete removal of the drains was 19.71 days in the early exercise group and 17.11 days in the exercise restriction group. @*Conclusions@#Exercise restriction after breast reconstruction did not lead to a significant difference in the drainage volume or the average time until drain removal. Thus, early exercise is recommended for improved shoulder mobility postoperatively. More long-term studies are needed to determine the effect of early exercise on shoulder mobility in prosthesis-based breast reconstruction patients.
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Background/Aims@#Acute kidney injury (AKI) is an underestimated yet important risk factor for the development of chronic kidney disease (CKD), characterized by tubulointerstitial fibrosis and tubular dedifferentiation. Tubular dedifferentiation, which is associated with the loss of epithelial markers and the gain of mesenchymal features, is thought to be involved in tubulointerstitial fibrosis. As protein kinase B/Akt is involved in the development of CKD, we investigated the role of Akt1, one of the three Akt isoforms, in a murine model of AKI-to-CKD progression. @*Methods@#We subjected C57BL/6 male mice to unilateral ischemia-reperfusion injury (UIRI) and harvested their kidneys after 6 weeks. Mice were divided into four groups, namely, wild-type (WT) UIRI, Akt1−/− UIRI, WT sham, and Akt1−/− sham. @*Results@#Akt1 (but not Akt2 or Akt3) was markedly activated in WT UIRI mice than in WT sham mice. Tubulointerstitial fibrosis and tubular dedifferentiation significantly increased in WT UIRI mice, but were attenuated in Akt1−/− UIRI mice. Both WT UIRI and Akt1−/− UIRI mice showed markedly upregulated transforming growth factor-β1 (TGF-β1)/Smad signaling compared with WT sham mice. However, TGF-β1/Smad expression did not differ between the two groups. The levels of phosphorylated GSK-3β, β-catenin, and Snail were attenuated in Akt1−/− UIRI mice compared with those in WT UIRI mice. @*Conclusions@#Deletion of Akt1 results in the attenuation of renal fibrosis and tubular dedifferentiation, independent of TGF-β1/Smad signaling, during AKI-to-CKD progression in a UIRI without contralateral nephrectomy model. Thus, Akt1 may serve as a therapeutic target in AKI-to-CKD progression.
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Purpose@#To evaluate the long-term outcomes of inverted internal limiting membrane (ILM) flap and ILM insertion in idiopathic macular hole (MH) and to compare the outcomes between the two techniques. @*Methods@#We retrospectively reviewed the medical records of 17 eyes that underwent an inverted ILM flap procedure (flap group, n = 9) or ILM insertion procedure (insertion group, n = 8) for idiopathic MH. Within each group, best-corrected visual acuity (BCVA) before surgery was compared with that at the final follow-up. The BCVA at the final follow-up was compared between the two groups. In addition, the incidence of restoration of the external limiting membrane (ELM) and ellipsoid zone was evaluated. @*Results@#The mean follow-up period was 25.1 ± 13.7 months after surgery. All MHs were closed after the surgery. In all 17 eyes, the logarithm of minimal angle of resolution BCVA had improved significantly from a mean value of 0.88 ± 0.23 before surgery to 0.42 ± 0.23 at the final follow-up (p < 0.001). The BCVA was significantly improved in both the flap group (from 0.92 ± 0.25 to 0.37 ± 0.29, p = 0.007) and the insertion group (from 0.83 ± 0.19 to 0.48 ± 0.15, p = 0.018). There was no significant difference in BCVA at the final follow-up between the two groups (p = 0.075). The incidence of restoration of the ELM and ellipsoid zone was significantly higher in the flap group (seven eyes, 77.8%) than in the insertion group (one eye, 12.5%). @*Conclusions@#Both inverted ILM flap and ILM insertion are effective in MH treatment. The restoration of retinal outer layers was better in the flap group. Further studies with a larger study population are needed to evaluate the long-term visual outcomes of the two methods.
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Purpose@#To evaluate the clinical characteristics and courses of Best disease in Korean patients. @*Methods@#We retrospectively reviewed the medical records of patients with Best disease followed-up for more than 12 months after diagnosis. The disease stage and best-corrected visual acuity (BCVA) at diagnosis, and stage progression during follow-up, were evaluated. The BCVA at diagnosis was compared to that at the final follow-up. The BCVA changes were compared between those evidencing stage progression and not. @*Results@#A total of 16 patients (32 eyes) were enrolled. The mean follow-up period was 52.1 ± 31.8 months. At diagnosis, three eyes had stage 1, nine stage 2, seven stage 3, 11 stage 4, and two stage 5 disease. During follow-up, stage progression was observed in nine eyes (28.1%). The mean logarithm of the minimal angle of resolution (logMAR) BCVA significantly worsened from 0.19 ± 0.19 at baseline to 0.30 ± 0.27 at the final follow-up (p = 0.004). In six eyes (18.8%), a deterioration of logMAR 0.2 or greater was noted. The extent of deterioration was greater in the nine eyes (0.25 ± 0.26) exhibiting stage progression than in the 24 eyes (0.05 ± 0.08) lacking such progression (p = 0.001). @*Conclusions@#The visual acuity of Best disease patients was relatively good at diagnosis. However, stage progression and visual deterioration were noted in some patients. Stage progression was associated with a poor visual prognosis.
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Background/Aims@#Acute kidney injury (AKI) is an underestimated yet important risk factor for the development of chronic kidney disease (CKD), characterized by tubulointerstitial fibrosis and tubular dedifferentiation. Tubular dedifferentiation, which is associated with the loss of epithelial markers and the gain of mesenchymal features, is thought to be involved in tubulointerstitial fibrosis. As protein kinase B/Akt is involved in the development of CKD, we investigated the role of Akt1, one of the three Akt isoforms, in a murine model of AKI-to-CKD progression. @*Methods@#We subjected C57BL/6 male mice to unilateral ischemia-reperfusion injury (UIRI) and harvested their kidneys after 6 weeks. Mice were divided into four groups, namely, wild-type (WT) UIRI, Akt1−/− UIRI, WT sham, and Akt1−/− sham. @*Results@#Akt1 (but not Akt2 or Akt3) was markedly activated in WT UIRI mice than in WT sham mice. Tubulointerstitial fibrosis and tubular dedifferentiation significantly increased in WT UIRI mice, but were attenuated in Akt1−/− UIRI mice. Both WT UIRI and Akt1−/− UIRI mice showed markedly upregulated transforming growth factor-β1 (TGF-β1)/Smad signaling compared with WT sham mice. However, TGF-β1/Smad expression did not differ between the two groups. The levels of phosphorylated GSK-3β, β-catenin, and Snail were attenuated in Akt1−/− UIRI mice compared with those in WT UIRI mice. @*Conclusions@#Deletion of Akt1 results in the attenuation of renal fibrosis and tubular dedifferentiation, independent of TGF-β1/Smad signaling, during AKI-to-CKD progression in a UIRI without contralateral nephrectomy model. Thus, Akt1 may serve as a therapeutic target in AKI-to-CKD progression.
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Purpose@#To evaluate the long-term outcomes of inverted internal limiting membrane (ILM) flap and ILM insertion in idiopathic macular hole (MH) and to compare the outcomes between the two techniques. @*Methods@#We retrospectively reviewed the medical records of 17 eyes that underwent an inverted ILM flap procedure (flap group, n = 9) or ILM insertion procedure (insertion group, n = 8) for idiopathic MH. Within each group, best-corrected visual acuity (BCVA) before surgery was compared with that at the final follow-up. The BCVA at the final follow-up was compared between the two groups. In addition, the incidence of restoration of the external limiting membrane (ELM) and ellipsoid zone was evaluated. @*Results@#The mean follow-up period was 25.1 ± 13.7 months after surgery. All MHs were closed after the surgery. In all 17 eyes, the logarithm of minimal angle of resolution BCVA had improved significantly from a mean value of 0.88 ± 0.23 before surgery to 0.42 ± 0.23 at the final follow-up (p < 0.001). The BCVA was significantly improved in both the flap group (from 0.92 ± 0.25 to 0.37 ± 0.29, p = 0.007) and the insertion group (from 0.83 ± 0.19 to 0.48 ± 0.15, p = 0.018). There was no significant difference in BCVA at the final follow-up between the two groups (p = 0.075). The incidence of restoration of the ELM and ellipsoid zone was significantly higher in the flap group (seven eyes, 77.8%) than in the insertion group (one eye, 12.5%). @*Conclusions@#Both inverted ILM flap and ILM insertion are effective in MH treatment. The restoration of retinal outer layers was better in the flap group. Further studies with a larger study population are needed to evaluate the long-term visual outcomes of the two methods.
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Purpose@#To evaluate the clinical characteristics and courses of Best disease in Korean patients. @*Methods@#We retrospectively reviewed the medical records of patients with Best disease followed-up for more than 12 months after diagnosis. The disease stage and best-corrected visual acuity (BCVA) at diagnosis, and stage progression during follow-up, were evaluated. The BCVA at diagnosis was compared to that at the final follow-up. The BCVA changes were compared between those evidencing stage progression and not. @*Results@#A total of 16 patients (32 eyes) were enrolled. The mean follow-up period was 52.1 ± 31.8 months. At diagnosis, three eyes had stage 1, nine stage 2, seven stage 3, 11 stage 4, and two stage 5 disease. During follow-up, stage progression was observed in nine eyes (28.1%). The mean logarithm of the minimal angle of resolution (logMAR) BCVA significantly worsened from 0.19 ± 0.19 at baseline to 0.30 ± 0.27 at the final follow-up (p = 0.004). In six eyes (18.8%), a deterioration of logMAR 0.2 or greater was noted. The extent of deterioration was greater in the nine eyes (0.25 ± 0.26) exhibiting stage progression than in the 24 eyes (0.05 ± 0.08) lacking such progression (p = 0.001). @*Conclusions@#The visual acuity of Best disease patients was relatively good at diagnosis. However, stage progression and visual deterioration were noted in some patients. Stage progression was associated with a poor visual prognosis.
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To the Editor:The authors regret that there were errors in the text. This notice corrects the numbers in the result of the Abstract. We changed the percentages indicating the decrease in the number of patients (adults and children) who visited the emergency department (EDs) during the study period.Content of correction:Before:“ Fewer patients, particularly children visited the EDs during the study period in 2020 than those in the previous (2018/2019) year period: the number of adult patient decreased by 46.4% and children by 76.9%.”After:“ Fewer patients, particularly children visited the EDs during the study period in 2020 than those in the previous (2018/2019) year period: the number of adult patient decreased by 26.0% and children by 62.0%.”
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Background@#Limited data exist on children's utilization of the emergency department (ED) in the ongoing coronavirus disease 2019 (COVID-19) pandemic. Thus, we aimed to examine ED utilization among pediatric patients and the impact of COVID-19 in one large city affected by the outbreak. @*Methods@#This retrospective study included data from six EDs in Daegu, Korea. We compared the demographic and clinical data of patients presenting to the ED during the COVID-19 pandemic (February 1st–June 30th 2020) with those of patients who visited the ED in this period during 2018 and 2019. @*Results@#Fewer patients, particularly children visited the EDs during the study period in 2020 than those in the previous (2018/2019) year period: the number of adult patient decreased by 46.4% and children by 76.9%. Although the number of patients increased from the lowest point of the decrease in March 2020, the number of pediatric patients visiting the ED remained less than half (45.2%) in June 2020 compared with that of previous years. The proportion of patients with severe conditions increased in adults, infants, and school-aged children, and consequently resulted in increased ambulance use and higher hospitalization rates. Fewer infants and young children but more school-aged children visited the ED with febrile illnesses in 2020 than in 2018/2019. @*Conclusion@#The COVID-19 pandemic has led to a substantial decrease in pediatric ED utilization. These findings can help reallocate human and material resources in the EDs during infectious disease outbreaks.
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Background@#Although loss of sensation in patients with breast cancer after mastectomy followed by breast reconstruction is an important factor affecting patients’ quality of life, the mechanism of sensory recovery is still unclear. Our study aimed to identify variables that affect sensory recovery, especially pain, in reconstructed breasts. @*Methods@#All patients with breast cancer who underwent mastectomy followed by immediate breast reconstruction, including nipple reconstruction or areolar tattooing, were included in this study. Sensation was evaluated in the nipple as an endpoint of sensation recovery of the whole breast. Patients rated pain severity using a 3-point verbal rating scale (VRS): grade 0, no pain; grade 1, mild to moderate pain; and grade 2, severe pain. The VRS was assessed by a single experienced plastic surgeon. @*Results@#In the univariate analysis, the odds ratio (OR) for sensation recovery was 0.951 for age (P=0.014), 0.803 for body mass index (P=0.001), 0.996 for breast volume before surgery (P=0.001), 0.998 for specimen weight after mastectomy (P=0.040), and 1.066 for the period between mastectomy and sensory assessment (P=0.003). In the multivariate analysis, the variables that showed a significant effect were age (OR, 0.953; P=0.034), the period between mastectomy and sensory assessment (OR, 1.071; P=0.006), and reconstruction using abdominal tissue instead of prosthetic reconstruction (OR, 0.270; P=0.004). @*Conclusions@#Based on our results, it can be inferred that aging has a negative impact on the recovery of sensation, breast sensation improves with time after surgery, and the recovery of sensation is better in prosthetic reconstruction.
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Mycoplasma pneumoniae pneumonia is one of the most common causes of community-acquired pneumonia in school-aged pediatric patients. Its severity varies ranging from mild respiratory symptoms to severe complications with atypical pneumonia. It can rarely produce nonpulmonary manifestations including thrombosis. We report a case of a 10-year-old girl with M. pneumoniae pneumonia accompanied by pulmonary embolism and splenic infarction. She was readmitted with fever and left lower chest pain when coughing and left upper abdominal pain. Chest radiography showed abnormalities in the lower lobe of the left lung and pleural effusion. Blood tests revealed an elevated C-reactive protein level. Chest computed tomography (CT) showed left pleural effusion, thromboembolism of the descending branch of the right pulmonary arterial as well as infarction at the upper portion of the spleen. Laboratory evaluations revealed positivity to antimycoplasma antibodies; IgM, sputum mycoplasma polymerase chain reaction, anticardiolipin IgM (18MPL: normal< 11), and IgG (32GPL: normal< 23). She was treated with intravenous clarithromycin and low-molecular heparin (LMWH, 1 mg/kg/day). Chest CT was performed on the 6th day of hospitalization, which showed improvement in thrombosis. We administered warfarin instead of LMWH to achieve an international normalized ratio 2.0–3.0. On the 11th day of hospitalization, the patient was uneventfully discharged. Following her discharge, we continued to administer warfarin to the patient. Three months later, we noticed that pulmonary embolism and splenic infarction had disappeared.
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Hypophosphatasia is a rare disease characterized by defective bone mineralization due to deficiency of tissue-nonspecific alkaline phosphatase. The patient was an 8-day-old male infant who presented with seizure since that day. Other symptoms included res piratory failure, requiring the use of a mechanical ventilator. Physical exami na tion revealed a large bulging anterior fontanelle, soft skull bone, and radial devia tion of both wrists. Laboratory examination showed normal serum calcium, low para thyroid hormone, normal 25-hydroxy vitamin D, and severely low alkaline phos phatase levels. Skeletal X-ray revealed dysplasia of the skull and cupping of the epiphysis of the limbs. Two heterozygous mutations (c.1052A>G, c.1559delT) of the ALPL gene were identified by Sanger sequencing. Thus, we report a case of confirmed lethal perinatal hypophos phatasia in Korea.
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Chronic kidney disease is developed commonly in type 2 diabetes mellitus (T2DM) and is the most common cause of end-stage renal disease and related cardiovascular complications. Meanwhile, despite the current standard of care including optimized glucose control and the use of single-agent blockade of the renin-angiotensin-aldosterone system (RAAS), patients with T2DM remain at increased risk for death and complications from cardiorenal causes. The recent studies using sodium-glucose cotransporter 2 (SGLT2) inhibitors have shown not only glucose lowering effect, but also a reduction in blood pressure, weight loss, and a lowering cardiovascular risk. Regarding renal outcomes, the use of SGLT2 inhibitor slows the progression of kidney disease compared to placebo when added to standard care. However, concern has been raised that currently available SGLT2 inhibitors in Korea may be also associated with improved renal outcomes with long-term treatment. As a result, we aimed to evaluate the effect of long-term SGLT2 inhibitor treatment on renal function in the patients with T2DM using meta-analysis. (Korean J Med 2020;95:236-243)
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Background@#Urgent-start peritoneal dialysis (PD) is applied to patients who need PD within two weeks but are able to wait for more than 48 hours before starting PD. To evaluate the usefulness of percutaneous PD catheter insertion in urgent-start PD, we reviewed the clinical outcomes of percutaneous catheter insertion with immediate start PD and surgical insertion with longer break-in time in Pusan National University Hospital. @*Methods@#This study included 177 patients who underwent urgent-start PD. Based on the PD catheter insertion techniques, the patients with urgent-start PD were divided into percutaneous (n = 103) and surgical (n = 74) groups. For the percutaneous group, a modified Seldinger percutaneous catheter insertion with immediate initiation of continuous ambulatory PD was performed by nephrologists. @*Results@#The percutaneous group showed higher serum urea nitrogen, creatinine, and lower serum albumin compared with the surgical group (P < 0.05). Ninety-day infectious and mechanical complications showed no significant differences between the two groups. Ninety-day peritonitis in the percutaneous group was 9.7% compared to 5.4% in the surgical group (P = not significant [NS]). Major leakage was 3.9% in the percutaneous group compared to 1.4% in the surgical group (P = NS). Overall infectious and mechanical complication-free survival was not significantly different between the two groups. The percutaneous group and surgical group showed no statistical difference with respect to catheter survival over the entire observation period (P = NS). @*Conclusion@#This study suggests that urgent-start PD can be applied safely with percutaneous catheter insertion by nephrologists with no break-in period.