Intrinsic and extrinsic factors causing hyperplasia of the prostate.

Prostatic hyperplasia is very common in elderly men and is a typical disease that reduces quality of life. Histologically, hyperplasia of the prostate gland causes obstruction at the bladder outlet, resulting in symptoms such as a weak urine stream. Various factors have been considered to cause histological enlargement of the prostate, but the underlying cause is still unknown. The factors that cause prostate hyperplasia can be broadly classified into intrinsic and extrinsic ones. Extrinsic factors include things that we directly come into contact with such as bacteria and food. On the other hand, intrinsic factors are those that cause changes in functions originally provided in the body due to some cause, including extrinsic factors, such as chronic inflammation and an imbalance of sex hormones. A large number of reports have been made to date regarding the etiology of prostatic hyperplasia, although they have not yet clarified the fundamental cause(s). The various factors currently known should be outlined for future research. Should it be possible to prevent this highly prevalent prostatic hyperplasia which is mainly cause of dcreasing quality of life, there is no doubt that it would be a huge contribution to humanity.

Development and preliminary evaluation of a novel procedure for creation of an ileal conduit stoma aimed at preventing parastomal hernia.

OBJECTIVES: Our previous study suggested that the operative procedure is critical for the development of parastomal hernia. We developed a novel procedure for the creation of an ileal conduit stoma to prevent parastomal hernia. Herein we evaluate the efficacy and safety of the procedure. METHODS: A total of 113 Japanese patients underwent radical cystectomy and ileal conduit diversion for bladder cancer from January 2017 through December 2021 at our institution. After excluding those with incomplete data, 103 patients consisting of 46 (44.7%) with the conventional procedure and 57 (55.3%) with the novel procedure were consecutively enrolled. The main points of the novel procedure are as follows: (1) the passage of the ileal conduit is ≤2.4 cm in diameter in principle; (2) the posterior rectus sheath and peritoneum are vertically incised 2 cm laterally from the middle of the stoma site to make an oblique passage for the ileal conduit; and (3) the anterior rectus sheath and posterior rectus sheath with peritoneum are fixed to the ileal conduit separately. RESULTS: Radiography-based parastomal hernia was observed in 11 patients (10.7%) with a median follow-up of 22.0 months. The incidences of parastomal hernia were 3.5% and 19.6% in the novel and the conventional procedure groups, respectively (p = 0.011). The former had a significantly lower cumulative incidence of parastomal hernia (p = 0.008, log-rank test). No specific complications associated with the procedure were observed. CONCLUSIONS: The results of the preliminary cohort study suggest that the novel procedure is safe and effective for the prevention of parastomal hernia.

[Two Cases of Retroperitoneal Synovial Sarcoma].

We experienced two cases of renal primary synovial sarcoma. Case 1: A 29-year-old man underwent laparoscopic radical nephrectomy and was originally diagnosed with renal cell carcinoma. Case 2: A 25-year-old man was treated by open radical nephrectomy since radiographical findings indicated tumor invasion to the ureter causing hydronephrosis. Both cases were pathologically diagnosed as renal synovial sarcomas, and were followed using computed tomography. Recurrence was observed within a year in both cases.

Are there differences in the characteristics of patients who respond to gemcitabine plus cisplatin chemotherapy and those who respond to pembrolizumab therapy for metastatic urothelial carcinoma? Multicenter retrospective study.

OBJECTIVES: To evaluate factors to predict overall survival of metastatic urothelial carcinoma patients treated with gemcitabine plus cisplatin chemotherapy or pembrolizumab therapy. METHODS: We retrospectively evaluated two metastatic urothelial carcinoma cohorts treated with (i) gemcitabine plus cisplatin or (ii) pembrolizumab. The gemcitabine plus cisplatin cohort was treated from December 2005 through December 2014 while the pembrolizumab cohort was treated from January 2018 through December 2020. Using multivariate analyses, we evaluated the risk factors for overall survival in each cohort and compared them. None of the gemcitabine plus cisplatin cohort patients were treated with pembrolizumab. All patients in the pembrolizumab cohort were treated with prior platinum-based chemotherapy. RESULTS: There were 184 patients in the gemcitabine plus cisplatin cohort and 91 in the pembrolizumab cohort. The mean follow-up periods were 714 and 284 days, respectively. In multivariate analysis, the risk factors for overall survival in the gemcitabine plus cisplatin cohort were liver metastasis, worse Eastern Cooperative Oncology Group performance status (1 or more), no primary site resection, and a high prognostic index (1 or more). In the pembrolizumab cohort, liver metastasis, bone metastasis, and worse Eastern Cooperative Oncology Group-performance status (1 or more), and high prognostic index (1 or more) were the risk factors for overall survival. In the pembrolizumab cohort, patients with a complete response or partial response during prior platinum-based chemotherapy had better overall survival with the following pembrolizumab treatment than those with stable or progressive disease (P = 0.004). CONCLUSIONS: Considering the similarity of these risk factors in two sequential treatments, it may be possible to predict the response to pembrolizumab according to the response to prior chemotherapy.

Significance of urinary liver-type fatty acid-binding protein in patients with normal renal function after undergoing intestinal urinary diversion: a preliminary study.

BACKGROUND: Liver-type fatty acid-binding protein (L-FABP) in urine is one of the early diagnostic biomarkers for acute and chronic kidney injuries. Although this protein is also identified in the intestine, there is no verified reference value for patients with intestinal urinary diversion (UD). The aim of the present study was to measure L-FABP values in such patients and compare them with the results for patients without UD. METHODS: Spot urine specimens were collected from 41 patients with UD and 50 subjects without UD with estimated glomerular filtration rates of over 60 ml/min/1.73 m2, and the L-FABP values were measured. The normal upper cutoff value in healthy subjects without UD is considered to be 7.24 µg/g Cr. First, the median values of the two groups were compared. Next, the subjects with negative proteinuria and without comorbidities associated with renal function were further selected and the median values of the groups were compared. RESULTS: The mean age was significantly higher in the UD group. The types of UD were ileal conduit (38 patients) and ileal neobladder (three patients). The median L-FABP value in the UD group was significantly higher than that in the non-diversion group (89.1 µg/g Cr vs. 2.0 µg/g Cr, p < 0.0001). After adjustment for their backgrounds, the median value remained higher in the UD group. CONCLUSIONS: L-FABP values in subjects with UD are higher than in those without UD. By this result, to develop a reference value in patients with intestinal UD population, further studies are required.

[Necrotizing Fasciitis of the Right Thigh Caused by Emphysematous Pyelonephritis Due to a Staghorn Stone : A Case Report].

We report a rare case of necrotizing fasciitis in the thigh induced by emphysematous pyelonephritis due to a staghorn stone. A 60-year-old female was diagnosed with a staghorn stone in the right kidney at another clinic. We referred her to another hospital for indication of percutaneous nephrolithotripsy. However, she chose not to visit the hospital. One year and three months later, she was transported to the emergencyward of our hospital because of a high fever and right hip joint pain. The diagnosis of right emphysematous pyelonephritis with a perinephric abscess was diagnosed by computed tomography. Transurethral ureteral stenting and percutaneous abscess drainage were performed and her condition improved. However, two weeks after the initial treatment, she developed swelling and pain in the right thigh. Computed tomographyrevealed multiple areas of gas in the right thigh and urgent debridement was performed. Escherichia coli was isolated from the cultures of urine and debrided tissues. The patient received several treatments, including two additional debridements, negative pressure wound therapy, and antimicrobial chemotherapy. Three months after the first debridement, the open wound of the right thigh was completely closed. Necrotizing fasciitis in the thigh due to emphysematous pyelonephritis is very rare. A favorable outcome was obtained byprompt debridement and negative pressure wound therapyin this case.

[Fever after Gemcitabine Administration is a Poor Prognostic Factor in Patients with Metastatic Urothelial Carcinoma : Multicenter Retrospective Study].

Gemcitabine (GEM) is currently a standard chemotherapeutic agent for metastatic urothelial carcinoma (mUC). Fever isknown to be an adverse effect of GEM ; however, itsincidence, etiology and clinical significance have not been evaluated. The objective of this study was to elucidate the characteristics and clinical significance of fever associated with GEM in patients with mUC receiving GEM plus cisplatin (GC) chemotherapy. Between 2005 and 2014, 184 patientswith mUC who received first-line GC therapy at 10 institutions were enrolled. GEM-associated fever (GEMAF) was defined as a body temperature ≥37.5ºC within 96 hours after administration of GEM with no evidence of specific conditions causing fever including infection. Clinical parametersbefore GC therapy were evaluated to determine predictorsof GEMAF. Furthermore, the impact of GEMAF on clinical outcomeswasals o evaluated. The median age was70 years and median follow-up was14.2 months. GEMAF wasobs erved in 44 patients (23.9%). In multivariate analysis, elevated C-reactive protein (CRP) before chemotherapy was an independent predictive factor for GEMAF (oddsratio 2.450, p＝0.041). There was a significant difference in progression-free survival (median 6.7 vs 8.0 months, p＝0.031) and cancer-specific survival (median 12.0 vs 15.8 months, p＝0.045) between patients with and without GEMAF. Results of this study suggest that GEMAF is a common adverse event of GC therapy for mUC and can be a poor prognostic factor. GEMAF may be associated with systemic inflammatory response induced by the tumor in patients with mUC.

Neoadjuvant chemotherapy with gemcitabine and cisplatin for muscle-invasive bladder cancer: multicenter retrospective study.

OBJECTIVES: The aim of this study was to evaluate the efficacy of neoadjuvant gemcitabine and cisplatin (GC) therapy for muscle-invasive bladder cancer (MIBC). METHODS: We retrospectively evaluated patients who underwent neoadjuvant GC therapy followed by radical cystectomy from April 2009 through December 2015 in the Sapporo Medical University Urologic Consortium. The efficacy of neoadjuvant chemotherapy (NAC) was assessed based on the pathological T0 (pT0) rate in radical cystectomy specimens, and the recurrence-free survival, cause-specific survival and overall survival (OS) rates. To compare the oncological benefit of NC with GC to that of the methotrexate, vinblastine, adriamycin and cisplatin (MVAC) regimen, we also utilized historical clinical data of patients who were treated with MVAC as NAC followed by radical cystectomy in our institute from 1986 through 2010. RESULTS: Fifty-eight patients receiving neoadjuvant GC therapy and 74 receiving neoadjuvant MVAC were included. The pT0 achieving rates were comparable between the two groups (20.7% vs. 18.9%, P = 0.83). Neoadjuvant GC was associated with a better 2-year OS rate than neoadjuvant MVAC for clinical T2 disease (95.2% vs. 70.8%, P = 0.036). In contrast, in patients with clinical T3 or more advanced disease, neoadjuvant MVAC provided more pT0 (20.0% vs. 5.6%, P = 0.07) and better 2-year OS than neoadjuvant GC (71.1% vs. 55.0%, P = 0.142), although the difference did not reach statistical significance. CONCLUSIONS: Neoadjuvant GC had no inferiority in oncological outcomes to MVAC for MIBC.

The discrepancy between serum creatinine and cystatin C can predict renal function after treatment for postrenal acute kidney injury: multicenter study and pooled data analysis.

BACKGROUND: Although serum cystatin C and creatinine are used as practical markers of renal function, the discrepancy between them in postrenal acute kidney injury (AKI) cases was reported. The aim of this study was to determine whether the preoperative serum cystatin C (pre-CysC) level could predict clinical outcomes after treatment in patients with postrenal AKI. METHODS: Patients who underwent urological interventions with postrenal AKI were enrolled in this prospective observational study. Associations among preoperative serum creatinine (pre-sCr), pre-CysC, and nadir postoperative serum creatinine (post-sCr) were evaluated. In addition, based on our results in combination with detailed data from the literature, a predictive equation for postoperative serum creatinine (post-sCr) was developed by simple regression analysis and validated using Bland-Altman plots. RESULTS: Finally, 19 patients were eligible for analysis in this study. The value calculated by subtracting pre-CysC (mg/L) from pre-sCr (mg/dl) had a strong correlation to the decrement of serum creatinine (r = 0.9508, p < 0.0001). We added the data of 16 patients obtained from the literature to our series, which were totally randomized into 2 groups, training set and validation set in a 2:1 ratio (n = 23 and 12, respectively) to develop and validate a predictive equation for post-sCr. The mean difference between the predictive and actual post-sCr, -0.68 mg/dl (95% CI -1.62 to 0.26) in the validation set was within the limits of agreement. CONCLUSION: We showed that the discrepancy between pre-sCr and pre-CysC could predict improvement of renal function after intervention in patients with postrenal AKI.

[A Case of Renal Cell Carcinoma in a Crossed Fused Ectopic Kidney Treated with Partial Nephrectomy].

A 76-year-old man came to the department of gastrointestinal medicine with lower left abdominal discomfort and constipation. A crossed fused ectopic kidney with a renal tumor in the left upper pole of the kidney was detected by computed tomography. We performed left partial nephrectomy safely in spite of the complicated shape and complexity of the blood vessels. The pathological diagnosis was clear cell renal cell carcinoma, pT3a, with a negative surgical margin. After surgery, renal function was well preserved.

[Clinical Evaluation of Diagnostic and Treatment Protocol of Idiopathic Retroperitoneal Fibrosis Incorporating Consideration of Possible IgG4-Related Disease].

About half of idiopathic retroperitoneal fibrosis might be classified as a IgG4-related disease, a newly characterized disease that is especially known to be sensitive to steroid therapy. We developed a new protocol for diagnosis and treatment of retroperitoneal fibrosis, which included aggressive diagnosis of IgG4- related disease. We retrospectively reviewed 22 cases with idiopathic retroperitoneal fibrosis that were diagnosed and treated according to our protocol. Of them, 10 patients (45.5%) had no evidence of IgG4- related disease (non-IgG4RD group), whereas 12 patients (54.5%) were diagnosed with IgG4-related disease (IgG4RD group). All patients received steroid therapy, and 13 patients (59.1%) underwent ureteral stenting or received prednisolone (PNS). There was no severe adverse event and planned steroid therapy was completed in all patients. In principle, maintenance steroid therapy was continued after induction therapy in the IgG4RD group, whereas steroid therapy was discontinued in the non-IgG4RD group. Regression of retroperitoneal plaque was achieved in all 22 patients. Four (57.1%) out of 7 patients and 3 (50.0%) out of 6 patients achieved freedom from ureteral stent or PNS in the non-IgG4RD group and IgG4RD group, respectively. All 3 patients with PNS became catheter-free after treatment, whereas only 4 (40.0%) of the 10 patients withureteral stent could become stent-free. Steroid therapy could be discontinued in 7 patients (70.0%) in the non-IgG4RD group. The results of this study suggest that similar efficacy of steroid therapy can be expected in the non-IgG4RD group and IgG4RD group.

Short-term functional and oncological outcomes of partial nephrectomy for renal cell carcinoma in patients with an anatomically or functionally solitary kidney: single-center experience.

BACKGROUND: We retrospectively investigated short-term functional and oncological outcomes of partial nephrectomy (PN) for the anatomically or functionally solitary kidney in patients with renal cell carcinoma. METHODS: Between 1993 and 2011, 193 partial nephrectomies were performed and 16 (8.3 %) had an imperative indication in our institution. The patients' characteristics, peri- and postoperative complications, surgical margin status and postoperative changes in estimated glomerular filtration rates (eGFR) were assessed. RESULTS: The median follow-up period was 31.2 months and median age was 69.5 years. Open and laparoscopic PN were performed for 13 and 2 patients, respectively. One patient received ex-vivo PN followed by autotransplantation. There was no case with a positive surgical margin. All patients survived at the final day of observation. Median preoperative eGFR was 48.67 mL/min/1.73 m(2) and the reduction rate of eGFR at 3 months after operation was 20.9 % (0-50.2). Three patients (18.8 %) required temporary hemodialysis after operation and all these patients had stage 4 chronic kidney disease (CKD) before operation. Only one patient needed chronic hemodialysis at 8 months after operation. CONCLUSIONS: PN can be performed safely and provides feasible functional and oncological outcomes. Preoperative CKD stage 4 patients may have a risk of temporary hemodialysis in the perioperative period.

Efficacy of cognitive behavioral therapy using self-check sheet for patients with nocturia in real-world clinical practice.

OBJECTIVES: We previously demonstrated the efficacy of cognitive behavioral therapy (CBT) using a self-check sheet for patients with nocturia in a randomized controlled study. Additionally, we investigated the efficacy of the intervention in real-world clinical practice. METHODS: Two hundred forty-three outpatients with complaint of nocturia who practiced CBT for 4 weeks using a self-check sheet were included in this trial, which took place from April 2021 to March 2022 in 20 institutions. RESULTS: Of the 243 patients, 215 who achieved 50% or more of the behavioral therapy tasks were included in the analysis. Their mean age ± SD was 77.1 ± 7.7. A significant decrease was observed in nighttime frequency at 4 weeks after CBT using self-check sheets (pre 3.3 and post 2.8, p < .001). Nighttime frequency was decreased one or more times and was defined as treatment success in 102 patients (47.4%). Pretreatment nighttime frequency in the treatment-success group was significantly higher than that of the failure group (3.5 ± 1.0 vs. 3.2 ± 1.0, p = .013). In multivariate logistic regression analysis, predictive factors of treatment success were pretreatment nocturnal frequency of four or more (odds ratio [OR] 1.82, 95% confidence interval [CI] 1.01-3.30; p = .046) and the absence of diabetes mellitus (OR 3.08, 95% CI 1.34-7.06; p = .008). CONCLUSIONS: CBT using a self-check sheet requiring less time, less labor, less cost, and less medication is very beneficial for both patients and medical staff in real-world clinical practice.

[Intrascrotal malignant mesothelioma diagnosed after surgery for hydrocele testis: a case report].

We report here a case of intrascrotal malignant mesothelioma, arising from the tunica vaginalis, which was diagnosed after surgery for hydrocele testis. A 52-year-old man underwent left hydrocelectomy for hydrocele testis. After pathological diagnosis as malignant mesothelioma from the specimen of tunica vaginalis, left radical orchiectomy was performed. The patient had no exposure to asbestos and there has been no evidence of recurrence.

[A case of Crohn's disease developing bladder rupture 4 months after laparoscopic sigmoidectomy with partial cystectomy for vesicosigmoidal fistula].

A 32-year-old well-nourished man having a vesicosigmoidal fistula due to Crohn's disease received laparoscopic sigmoidectomy with partial cystectomy. The bladder wall was closed with an all-layer running suture and additional interrupted sutures using 2-0 Vicryl. Four months after surgery, the suture site on the bladder showed perforation to the abdominal cavity. Since the same event occurred again 6 months after surgery, open partial cystectomy was performed to repair the perforated site 8 months after the initial surgery. The perforated site showed a thinning bladder wall composed of normal urothelium, scar tissue and thin detrusor muscle. Non-caseating granuloma was not found in the specimen, even though it was slightly observed in the margin of the detrusor muscle resected in the initial surgery. Although it was possible that the persisting activity of Crohn's disease, subclinical impaired nutrition due to Crohn's disease or insufficient suturing of the bladder wall were involved in the bladder rupture, the definitive cause remains unknown.

Heat shock protein 90 is a new potential target of anti-rejection therapy in allotransplantation.

The critical roles of heat shock protein 90 (HSP90) in immune reactions associated with viral infection and autoimmune disease are well known. To date, however, its roles in the alloimmune response and the immunosuppressive effect of HSP90 inhibitors in allotransplantation have remained unknown. The purpose of this study was to examine the therapeutic efficacy of the HSP90 inhibitor 17-DMAG in allotransplantation models. C57BL/6 (H-2b) and BALB/c (H-2d) mice were used as donors for and recipients of skin and heart transplantation, respectively. Treatment with 17-DMAG (daily i.p.) or a vehicle was initiated 3 days before transplantation. Immunological outcomes were assessed by histopathological examinations, flow cytometric analysis, quantitative RT-PCR, ELISA, ELISPOT assay, and MLR. 17-DMAG treatment significantly prolonged the survival of both skin and heart allografts. In 17-DMAG-treated mice, donor-reactive splenocytes producing IFN-γ were significantly reduced along with the intragraft mRNA expression level and serum concentration of IFN-γ. Intragraft mRNA expression of cytokines and chemokines associated with both innate and adaptive immunity was suppressed in 17-DMAG-treated group. MLR showed suppression of the donor-specific proliferation of CD4 + T and CD19 + B cells in the spleens of 17-DMAG-treated mice. 17-DMAG treatment also reduced the number of activated NK cells. Furthermore, the treatment lowered the titers of donor-specific antibodies in the serum and prolonged a second skin allograft in mice sensitized by previous skin transplantation. HSP90 inhibition by 17-DMAG can affect various immune responses, including innate immunity, adaptive immunity, and humoral immunity, suggesting its therapeutic potential against acute rejection in allotransplantation.

Successful therapeutic strategy for a patient with obese end-stage kidney disease by simultaneous laparoscopic sleeve gastrectomy and implantation of a buried peritoneal dialysis catheter: A case report.

For morbidly obese patients with end-stage kidney disease (ESKD), there are often difficulties in accessing, implementing, and maintaining kidney replacement therapy (KRT). Although recent weight-loss surgery has the potential to solve these problems, its therapeutic strategy and appropriate perioperative management for morbidly obese patients with ESKD have not been established. Here, we describe the case history of a 47-year-old man diagnosed with ESKD due to obesity-related glomerulopathy with an uncorrected estimated glomerular filtration rate (eGFR) of 16.1 ml/min. He hoped for kidney transplantation but was not eligible due to his high body mass index (BMI) (36.9 kg/m2). Therefore, a combination strategy for both attaining weight loss and preparing for KRT was needed. We performed modified laparoscopic sleeve gastrectomy (LSG) combined with a buried catheter for peritoneal dialysis (PD), which resulted in reduction of multiple surgical invasions while simultaneously preparing for PD. After these operations, his body mass dropped to below 30.0 kg/m2, making him a candidate for kidney transplantation, while maintaining PD. Finally, he was able to have kidney transplantation with success. Collectively, in this case, our novel therapeutic approach was able to avoid multiple surgeries, to assist catheter insertion by laparoscopy, and to provide optimal KRT for an obese patient with ESKD. Simultaneous LSG and implantation of a buried PD catheter may be a promising strategy for morbidly obese patients with ESKD.

A case with fistula formation between a perinephric retroperitoneal abscess and the duodenum: successful outcome after conservative management.

A 67-year-old woman diagnosed with pyonephrosis and perinephric abscess because of an impacted urinary stone in the pelvicoureteric junction was admitted to the hospital with a high-grade fever. Although construction of a right nephrostomy for drainage of the abscess improved her general condition, she had a fever again 2 weeks after the initial treatment. Computed tomography revealed a persistent perinephric retroperitoneal abscess and a second drainage procedure was performed. Then, imaging examination revealed fistula formation between the cavity of the perinephric retroperitoneal abscess and the duodenum. The patient received conservative management including percutaneous drainage, discontinuation of oral intake, and antimicrobial chemotherapy. Three days after the second drainage and discontinuation of oral intake, imaging examination revealed complete closure of the fistula. Fistula formation between a perinephric abscess and the duodenum is very rare but a favorable outcome was obtained by our conservative management.

[Clinical outcome of refractory seminoma].

We retrospectively reviewed 67 patients with pure seminoma who were treated in our hospital between 1991 and 2009. Fifteen (22.4%) patients had metastatic or recurrent disease and underwent chemotherapy. Induction chemotherapy provided freedom from disease with no recurrence in 9 patients. On the other hand, 6 patients had chemotherapy-resistant seminoma (refractory group). We herein report the clinical features of the refractory group. Although we could not determine the risk factors for refractory disease, clinical stage III disease was resistant to induction chemotherapy. The refractory group consisted of 2 patients with recurrent disease after prophylactic radiation therapy for stage I disease, 1 with stage IIB and 3 with stage IIIC disease. In the refractory group, 3 patients obtained freedom from disease after additional chemotherapy with salvage surgery. However, 3 patients died from cancer in spite of multiple salvage treatments. Salvage radiation therapy was performed for inoperable metastatic disease in 3 patients and might have contributed to disease control in 2 patients. Some patients with pure seminoma can develop refractory disease, although the prediction is difficult. Multimodality therapy including salvage radiation possibly provides survival benefit.

[Neurotoxicity of valacyclovir in a peritoneal dialysis patient].

The patient was a 67-year-old man with a 2-year history of peritoneal dialysis for end-stage renal disease due to hypertensive nephropathy. He presented to a dermatologist with a complaint of pain in the right femoral region. He was diagnosed as having herpes zoster and valacyclovir, 1,000 mg/day, was prescribed. After 5 days of taking valacyclovir orally, he felt fretful and hallucinations appeared. He was admitted to our hospital and was hospitalized in our urology ward. We diagnosed his condition as neurotoxicity caused by an overdose of valacyclovir. As his general condition was stable, he was treated only by continuation of peritoneal dialysis. After 7 days of hospitalization, the neurotoxicity completely disappeared and he left the hospital. His serum acyclovir concentration at admission was 20.20 µg/l, and was reduced to 0.7 µg/l when he left the hospital. This supported our diagnosis of valacyclovir-induced neurotoxicity. In this case, valacyclovir should have been reduced to 500 mg/day, considering his renal function. Although we could treat the patient only by continuation of peritoneal dialysis, hemodialysis seems to be an effective treatment method in the case of unstable general condition or severe adverse effects, because it can eliminate the serum acyclovir.