Diagnostic Assessment of Deep Learning Algorithms for Frozen Tissue Section Analysis in Women with Breast Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#Assessing the metastasis status of the sentinel lymph nodes (SLNs) for hematoxylin and eosin–stained frozen tissue sections by pathologists is an essential but tedious and time-consuming task that contributes to accurate breast cancer staging. This study aimed to review a challenge competition (HeLP 2019) for the development of automated solutions for classifying the metastasis status of breast cancer patients. @*Materials and Methods@#A total of 524 digital slides were obtained from frozen SLN sections: 297 (56.7%) from Asan Medical Center (AMC) and 227 (43.4%) from Seoul National University Bundang Hospital (SNUBH), South Korea. The slides were divided into training, development, and validation sets, where the development set comprised slides from both institutions and training and validation set included slides from only AMC and SNUBH, respectively. The algorithms were assessed for area under the receiver operating characteristic curve (AUC) and measurement of the longest metastatic tumor diameter. The final total scores were calculated as the mean of the two metrics, and the three teams with AUC values greater than 0.500 were selected for review and analysis in this study. @*Results@#The top three teams showed AUC values of 0.891, 0.809, and 0.736 and major axis prediction scores of 0.525, 0.459, and 0.387 for the validation set. The major factor that lowered the diagnostic accuracy was micro-metastasis. @*Conclusion@#In this challenge competition, accurate deep learning algorithms were developed that can be helpful for making a diagnosis on intraoperative SLN biopsy. The clinical utility of this approach was evaluated by including an external validation set from SNUBH.

Effects of thickness and background on the masking ability of high -trasnlucent zirconias

Purpose@#The purpose of this study was to compare and evaluate the masking ability of three types of high translucent zirconia according to the various thicknesses and backgrounds. @*Materials and Methods@#Using three types of high-translucency zirconia (Ceramill zolid fx white, Ceramill zolid ht+ white, Ceramill zolid ht+ preshade A2), 10 cylindrical specimens were fabricated in 10mm diameter and each with four thicknesses (0.6 mm, 1.0 mm, 1.5 mm, 2.0 mm), respectively by CAD/CAM method. The background was 10 mm in diameter and 10 mm in thickness. A1, A2, A3 flowable resin backgrounds, blue-colored core resin background, and Ni-Cr alloy background were prepared, and black, white backgrounds provided by the spectrophotometer manufacturer (x-rite, Koblach, Austria) were used. zirconia specimens and the background specimen were stacked to measure L, a*, b* with Spectrophotometer (Color i5, x-rite, Koblach, Austria) and the ∆E value with the other background is calculated. The Calculated mean ∆E values were compared based on perceptibility threshold 1.0 and acceptability threshold 3.7. Nonparametric tests such as Kruskal-Wallis test were performed to verify statistical significance (α = 0.05). @*Results@#There was a significant difference in the mean ∆E value according to the zirconia type, background and thickness change (P = 0.000). @*Conclusion@#According to the results of this study, the pre-colored high-translucent zirconia can obtain the desired zirconia shade when it is restored on teeth, composite resins, and abutments except for the blue resin core.

Codeless Deep Learning of COVID-19 Chest X-Ray Image Dataset with KNIME Analytics Platform / 대한의료정보학회지

Objectives@#This paper proposes a method for computer-assisted diagnosis of coronavirus disease 2019 (COVID-19) through chest X-ray imaging using a deep learning model without writing a single line of code using the Konstanz Information Miner (KNIME) analytics platform. @*Methods@#We obtained 155 samples of posteroanterior chest X-ray images from COVID-19 open dataset repositories to develop a classification model using a simple convolutional neural network (CNN). All of the images contained diagnostic information for COVID-19 and other diseases. The model would classify whether a patient was infected with COVID-19 or not. Eighty percent of the images were used for model training, and the rest were used for testing. The graphic user interface-based programming in the KNIME enabled class label annotation, data preprocessing, CNN model training and testing, performance evaluation, and so on. @*Results@#1,000 epochs training were performed to test the simple CNN model. The lower and upper bounds of positive predictive value (precision), sensitivity (recall), specificity, and f-measure are 92.3% and 94.4%. Both bounds of the model’s accuracies were equal to 93.5% and 96.6% of the area under the receiver operating characteristic curve for the test set. @*Conclusions@#In this study, a researcher who does not have basic knowledge of python programming successfully performed deep learning analysis of chest x-ray image dataset using the KNIME independently. The KNIME will reduce the time spent and lower the threshold for deep learning research applied to healthcare.

Challenge for Diagnostic Assessment of Deep Learning Algorithm for Metastases Classification in Sentinel Lymph Nodes on Frozen Tissue Section Digital Slides in Women with Breast Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#Assessing the status of metastasis in sentinel lymph nodes (SLNs) by pathologists is an essential task for the accurate staging of breast cancer. However, histopathological evaluation of sentinel lymph nodes by a pathologist is not easy and is a tedious and time-consuming task. The purpose of this study is to review a challenge competition (HeLP 2018) to develop automated solutions for the classification of metastases in hematoxylin and eosin–stained frozen tissue sections of SLNs in breast cancer patients. @*Materials and Methods@#A total of 297 digital slides were obtained from frozen SLN sections, which include post–neoadjuvant cases (n = 144, 48.5%) in Asan Medical Center, South Korea. The slides were divided into training, development, and validation sets. All of the imaging datasets have been manually segmented by expert pathologists. A total of 10 participants were allowed to use the Kakao challenge platform for six weeks with two P40 GPUs. The algorithms were assessed in terms of the AUC (area under receiver operating characteristic curve). @*Results@#The top three teams showed 0.986, 0.985, and 0.945 AUCs for the development set and 0.805, 0.776, and 0.765 AUCs for the validation set. Micrometastatic tumors, neoadjuvant systemic therapy, invasive lobular carcinoma, and histologic grade 3 were associated with lower diagnostic accuracy. @*Conclusion@#In a challenge competition, accurate deep learning algorithms have been developed, which can be helpful in making frozen diagnosis of intraoperative sentinel lymph node biopsy. Whether this approach has clinical utility will require evaluation in a clinical setting

Recommendation for the Peripheral Blood Cell Morphology Report

There is considerable heterogeneity in the peripheral blood smear reports across different diagnostic laboratories, despite following the guidelines published by the International Council for Standardization in Haematology (ICSH). As standardization of reports can facilitate communication and consequently the diagnostic efficiency in both laboratories and clinics, the standardization committee of the Korean Society for Laboratory Hematology aimed to establish a detailed guideline for the standardization of peripheral blood smear reports. Based on the ICSH guidelines, additional issues on describing and grading the peripheral blood smear findings were discussed. In this report, the proposed guideline is briefly described.

An Automated Draft Report Generator for Peripheral Blood Smear Examinations Based on Complete Blood Count Parameters

BACKGROUND: Complete blood count (CBC) results play an important role in peripheral blood smear (PBS) examinations. Many descriptions in PBS reports may simply be translated from CBC parameters. We developed a computer program that automatically generates a PBS draft report based on CBC parameters and age- and sex-matched reference ranges. METHODS: The Java programming language was used to develop a computer program that supports a graphical user interface. Four hematology analyzers from three different laboratories were tested: Sysmex XE-5000 (Sysmex, Kobe, Japan), Sysmex XN-9000 (Sysmex), DxH800 (Beckman Coulter, Brea, CA, USA), and ADVIA 2120i (Siemens Healthcare Diagnostics, Eschborn, Germany). Input data files containing 862 CBC results were generated from hematology analyzers, middlewares, or laboratory information systems. The draft reports were compared with the content of input data files. RESULTS: We developed a computer program that reads CBC results from a data file and automatically writes a draft PBS report. Age- and sex-matched reference ranges can be automatically applied. After examining PBS, users can modify the draft report based on microscopic findings. Recommendations such as suggestions for further evaluations are also provided based on morphological findings, and they can be modified by users. The program was compatible with all four hematology analyzers tested. CONCLUSIONS: Our program is expected to reduce the time required to manually incorporate CBC results into PBS reports. Systematic inclusion of CBC results could help improve the reliability and sensitivity of PBS examinations.

A Case of Hemolytic Disease of the Fetus and Newborn due to Anti-S Antibody: The First Case in Korea / 대한수혈학회지

A full term male infant was admitted to the neonatal intensive care unit due to jaundice and mild hemolytic anemia within the first 24 hours of his life. The total serum bilirubin level was 11.2 mg/dL at 24 hours of age. The patient was RhD positive and blood group A, and his mother was RhD positive and blood group B. The direct and indirect antiglobulin tests of the infant were all positive. On antibody screening and identification tests, anti-S antibodies were identified from both the infant and mother. The RBC phenotyping for S antigen revealed positive for infant and negative for mother. This report documents the first case of hemolytic disease of the fetus and newborn due to the anti-S antibody in Korea.

Should We Place Ureteral Stents in Retroperitoneal Laparoscopic Ureterolithotomy?: Consideration of Surgical Techniques and Complications

PURPOSE: There is some debate over the necessity of ureteral stenting after laparoscopic ureterolithotomy. We evaluated the need for ureteral stenting after retroperitoneal laparoscopic ureterolithotomy (RLU). MATERIALS AND METHODS: Between January 2009 and January 2013, 41 patients underwent RLU to remove upper ureteral stones. The retroperitoneal approach was used in all patients by a single surgeon. A double J (D-J) stent was placed in the first 17 patients after the procedure but not in any of the next 24 patients. RESULTS: The mean patient age, serum creatinine levels, and stone size were not significantly different between the two groups. The stone-free rate was 100%. The mean operative time was significantly shorter in the stentless group than in the stent group (59.48 minutes vs. 77.88 minutes, p<0.001). Parenteral analgesic use and anticholinergic medication use were observed in the stent group only. The blood loss, drain removal day, and hospital stay were not significantly different between the two groups. No other significant complications occurred during or after the operation in any patients. CONCLUSIONS: RLU is a safe and effective treatment modality for large impacted ureteral stones. In this study, D-J stent placement was not necessary after RLU. In the future, large-scale studies of RLU without D-J stenting, especially on the frequency of the development of complications according to the surgical technique, may be needed.

Efficacy of Repeated Transrectal Prostate Biopsy in Men Younger Than 50 Years With an Elevated Prostate-Specific Antigen Concentration (>3.0 ng/mL): Risks and Benefits Based on Biopsy Results and Follow-up Status

PURPOSE: Prostate cancer is rare in men younger than 50 years. Digital rectal examination (DRE) and measurement of prostate-specific antigen (PSA) concentrations are standard screening methods for detecting prostate cancer. We retrospectively investigated the risks and benefits of repeated transrectal ultrasonography-guided prostate needle biopsies in relation to the follow-up status of men younger than 50 years with a consistently high PSA concentration (>3.0 ng/mL). MATERIALS AND METHODS: During the period from January 2000 through February 2013, we reviewed patient's ages, dates of procedures, DRE results, frequencies of biopsies, results of the biopsies, periods of follow-up, PSA concentrations, and prostate volumes in Chonbuk National University Hospital records. We conducted telephone interviews in patients who did not undergo regular follow-up. RESULTS: The mean age of the patients was 44.7 years, and the mean PSA concentration was 8.59 ng/mL (range, 3.04-131 ng/mL) before biopsy. The PSA concentration was significantly different (p3.0 ng/mL).

Ureteral Penetration Caused by Drilling During Internal Pelvic Bone Fixation: Delayed Recognition / 대한배뇨장애요실금학회지

A 49-year-old man was referred to our department with profuse serous fluid discharge from a Penrose drain after undergoing internal fixation with metal screws for multiple pelvic bone fractures. A definite ureteral penetration was identified that was orientated from the lateral to the medial aspect of the right distal ureter. The patient was surgically treated with excision of the 2-cm injured ureteral segment, end-to-end ureteroureterostomy, and double J ureteral stent placement. To our knowledge, a penetrating ureteral injury caused by bone drilling has not been reported previously in the published literature. This case shows that surgeons who do pelvic surgery, including orthopedic surgeons, should be familiar with the anatomical relationship of the ureter and its potential injuries.

Efficacy and Safety of the TVT-SECUR(R) and Impact on Quality of Life in Women with Stress Urinary Incontinence: A 2-Year Follow-Up

PURPOSE: As recently reported, the short-term results of the tension-free vaginal tape SECUR(R) (TVT-S) procedure seem to be similar to those of the conventional transobturator tape (TOT) procedure. However, results of efficacy and satisfaction with TVT-S are insufficient in patients with more than 1 year of follow-up. Therefore, we evaluated the results of the TVT-S procedure in women with stress urinary incontinence (SUI) during 2 years. MATERIALS AND METHODS: We evaluated 51 patients with clinical and urodynamic diagnoses of SUI who underwent the TVT-S procedure from March 2008 to February 2009. Preoperative evaluation included a history, cough stress test with full bladder, urodynamic study, and incontinence quality of life (I-QoL) questionnaire. Following the postoperative period, urinary incontinence status was examined through a physical examination and the I-QoL questionnaire was completed in an outpatient setting or by telephone. RESULTS: Data from 2 years of follow-up were available for 46 of 51 patients. The cure rate was 80.4% at 1 month after TVT-S and 76.0% at 2 years after TVT-S. The cure or improvement rate was 93.5% at 1 month after TVT-S and 86.8% at 2 years after TVT-S. The mean total I-QoL score increased by 42 points at 1 month after TVT-S (p<0.026) and by 32 points at 2 years after TVT-S (p<0.013). Most patients reported significant improvements in quality of life. At the 2-year follow-up, there were no significant complications related to TVT-S. CONCLUSIONS: The results of this study suggest that TVT-S is an efficient and safe procedure for the improvement of both the quality of life of the patients and the SUI itself.

Newly Discovered Pseudoaneurysm after Embolization of a Renal Arteriovenous Fistula with a Pseudoaneurysm following a Renal Stab Wound

Post-traumatic arteriovenous fistula (AVF) and pseudoaneurysm are rare, and mostly occur in stab wound patients. Suspected AVF and pseudoaneurysm requires angiography, with planned simultaneous embolization. Superselective embolization is generally a safe and effective treatment modality for AVF and pseudoaneurysm with minimal associated morbidity. Rare complications of the embolization do occur, including renal abscess, postembolization syndrome, impaired renal function, pulmonary embolism caused by migration of coils, and allergic reaction. We present here the case of a man who presented with a newly discovered pseudoaneurysm after embolization of a renal AVF with pseudoaneurysm after a renal stab wound.

Crystal Deposits on Renal Papillae in Stone Formers

PURPOSE: Papillary "Randall's plaques" are theorized to act as nidi for urinary stone formation. In this study, we used endoscopic examination and intraoperative biopsy of renal papilla in stone formers undergoing percutaneous nephrolithotomy (PNL) to investigate the correlation between Randall's papillary plaque and primary stone composition and metabolic risk factors. MATERIALS AND METHODS: A total of 34 patients with renal stones were enrolled. During PNL performed for stone removal, biopsy specimens were taken from selected papilla. We evaluated constituents such as volume, sodium, uric acid, calcium, oxalate, and citrate from 24-hour urine samples, and calcium, sodium, uric acid, phosphate, potassium, and chloride from serum samples 1 month after PNL. RESULTS: We identified Randall's plaque in 26 patients as irregular, whitish lesions, generally located on the papillary tip. We performed intraoperative biopsies of papilla in the kidneys of stone formers and of known regions of crystal deposits in the interstitial tissue surrounding the ducts. There was no correlation between serum variables, 24-hour urine constituents, and presence of plaque. However, 24-hour urine volume was negatively correlated with the presence of plaque. The incidence of papillary plaques varied with the primary composition of extracted stones and was 80% for calcium oxalate, 92% for calcium phosphate, 50% for uric acid, and 25% for struvite stones (p=0.035). CONCLUSIONS: The incidence of papillary Randall's plaques in patients with nephrolithiasis varied with the primary composition of formed urinary stones. Randall's plaques are found in most patients with calcium stones. Our findings suggest that the presence of papillary plaque is associated with calcium nephrolithiasis and may contribute to the pathogenesis, treatment, and prevention of calcium urinary stones.

Hypospadias Repair: Recent Concept and Development in Surgical Techniques / 대한비뇨기과학회지

Hypospadias is one of the most common congenital anomalies defined by abortive development of the urethral spongiosum and the ventral prepuce. The current standard of care for hypospadias includes not only a functional penis adequate for sexual intercourse and urethral reconstruction offering the ability to stand to urinate, but also a satisfactory cosmetic result. The techniques of hypospadias surgery continue to evolve. The major technical advances in hypospadias surgery that have improved surgical outcomes are 1) Preservation of the urethral plate, 2) Incision of the urethral plate, 3) Dorsal midline plication, 4) Deepithelized urethroplasty dartos flap coverage, and 5) Two stage alternative techniques. Tubularized incised plate repair has been the mainstay for distal hypospadias. In cases of proximal hypospadias, one-stage repairs such as the Duckett repair or the Koyanagi repair have been well established, while two-stage repairs remain important alternatives. Whether dorsal plication or ventral lengthening should be used to correct penile curvature is still controversial, and long-term results are required. This article reviews the new concept and development in surgical techniques.

Bladder Rupture during Voiding Cystourethrography / 대한비뇨기과학회지

A ruptured bladder, or extravasation from the bladder, is almost always associated with trauma. Spontaneous extravasation, or iatrogenic extravasation, is extremely rare, with only few reported cases. Herein, two cases of bladder rupture, which occurred during voiding cystourethrography (VCUG), one in an 18 month old patient and the other in a 6 week old patient, due to instill dye by high pressure, are presented.

Analysis of Prognostic Factors in Patients with Fournier's Gangrene

BACKGROUND: To evaluate prognostic factors such as age, associated disease, laboratory and clinical data, which can affect prognosis of patients with Fournier's gangrene. MATERIALS AND METHODS: 27 patients were included in this study. All underwent treatment during past 15-year in our department. Medical records were reviewed with respect to age at presentation, extent of disease, laboratory data and bacteriology, associated disease, and clinical course. Also involved surface area was measured by the rule used in burn patients. Statistical analysis was made by Mann Whitney U test and Fisher's exact test. RESULTS: Of 27 patients, 4 died and 23 survived. The mean age was 55.4+/-13.7. The most common underlying disease was diabetes mellitus. In comparison of survival and non-survival groups, there were significant differences in duration of symptom before hospitalization, total surface area involved, laboratory data including serum albumin, creatinine, and WBC count on CBC. However, there was no difference in hospital stay, age, underlying disease, serum BUN, infected organisms, and urinary or fecal diversion. CONCLUSION: We conclude that the unfavorable factors affecting survival are duration of symptom before hospitalization, total surface area involved, serum albumin and creatinine level, and WBC count on CBC. The survival was, however, not associated with bacteriological factors, hospital stay, age, urinary or fecal diversion, and underlying diseases such as diabetes, and cancer.

Analysis of Prognostic Factors in Patients with Fournier's Gangrene

BACKGROUND: To evaluate prognostic factors such as age, associated disease, laboratory and clinical data, which can affect prognosis of patients with Fournier's gangrene. MATERIALS AND METHODS: 27 patients were included in this study. All underwent treatment during past 15-year in our department. Medical records were reviewed with respect to age at presentation, extent of disease, laboratory data and bacteriology, associated disease, and clinical course. Also involved surface area was measured by the rule used in burn patients. Statistical analysis was made by Mann Whitney U test and Fisher's exact test. RESULTS: Of 27 patients, 4 died and 23 survived. The mean age was 55.4+/-13.7. The most common underlying disease was diabetes mellitus. In comparison of survival and non-survival groups, there were significant differences in duration of symptom before hospitalization, total surface area involved, laboratory data including serum albumin, creatinine, and WBC count on CBC. However, there was no difference in hospital stay, age, underlying disease, serum BUN, infected organisms, and urinary or fecal diversion. CONCLUSION: We conclude that the unfavorable factors affecting survival are duration of symptom before hospitalization, total surface area involved, serum albumin and creatinine level, and WBC count on CBC. The survival was, however, not associated with bacteriological factors, hospital stay, age, urinary or fecal diversion, and underlying diseases such as diabetes, and cancer.

Biochemical Characteristics of Serum and Urine in the Patients with Uric Acid Stone / 대한비뇨기과학회지

PURPOSE: We investigated the biochemical characteristics of serum and urine in the patients suffering with uric acid stone. MATERIALS AND METHODS: A total of 99 patients suffering with uric acid stone underwent routine urine analysis and 24-hour urine analysis for determining the urinary calculi risk factors. We conducted serum analysis for the stone risk factors and also analysis of the stone analysis. To compare the stone risk factors, 93 patients with calcium stone were identified and then the biochemical risk factors in the serum and urine were evaluated. RESULTS: The mean age of patients with uric acid stone was 56.5+/-12.4 years and the mean age of the patients with calcium stone was 40.2+/-11.5 years. Serum uric acid, cholesterol and triglyceride were all significantly increased in the patients with uric acid stone compared to that in the patients with calcium stone. The patients with uric acid stone showed a lower urinary pH and also lower urinary uric acid and citric acid excretion compared with those patients with calcium stone. The composition of the uric acid stone was mixed with calcium in 63.6 percent of the stones and 36.4% of the stones were pure. CONCLUSIONS: The patients with uric acid stone had higher serum uric acid, cholesterol and triglyceride, and they had a lower urinary pH and lower uric acid and citric acid excretion as compared with the patients with calcium stone. Uric acid-calcium mixed stone was most common in the patients with uric acid stone. There is a great likelihood of uric acid stone in the patients with stone who have one or more of the above mentioned biochemical characteristics. Therefore, these factors are important to conduct metabolic evaluation for preventing stone recurrence.

The Stone Risk Factors for Stone Patients with Hypertension / 대한비뇨기과학회지

Purpose: In order to identify the stone risk factors for stone patients with hypertension, we analyzed the stone metabolic studies of stone patients with hypertension and stone patients without hypertension. Materials and Methods: Between January 1998 and December 2005, we analyzed 92 urinary calculi patients with hypertension, and we also 210 urinary calculi patients who had no history of hypertension as a control group. Hypertension was defined as systolic blood pressure >140 mmHg or a diastolic pressure >90mmHg or both, or those patients who were on drug therapy for hypertension. We evaluated such metabolic risk factors as calcium, sodium, potassium, chloride, uric acid, oxalate, phosphorus, the total urine volume and urine citrate level of the 24-hour urine collection, and the uric acid, calcium, phosphorus, cholesterol, triglyceride from the serum. Results: The mean age was 53.2+/-11.2 in the hypertensive group and 48.4+/-14.0 in the normotensive group. There were significant differences between the hypertensive group and the normotensive group for the body mass index (BMI) (28.7+/-0.9kg/m2 vs 25.1+/-1.1kg/m2, respectively), weight (73.2+/-3.2kg vs 67.4+/-2.1kg respectively) and urine calcium (262.4+/-21.7 mg/day vs 205.2+/-22.3mg/day respectively), uric acid (662.7+/-184.3mg/ day vs 578.3+/-179.2 mg/day respectively). Moreover, there were significant differences between the two groups for total cholesterol (198.5+/-47.4mg/dl vs 167.1+/-42.5 mg/dl respectively) and triglyceride (207.5+/-109.5mg/dl vs 160.8+/-107.1 mg/dl respectively). Conclusions: Our results suggest that higher urinary calcium excretion and higher uric acid excretion appear to be the characteristic risk factors in the hypertensive group. Hypercholesterolemia, hypertriglyceridemia and an excessive BMI are also related to stone patients with hypertension.

Metabolic Stone Risk Factors Associated with Papillary Calcification on Unenhanced Spiral Computed Tomography / 대한비뇨기과학회지

PURPOSE: Increasing evidence suggests that Randalls plaque contributes to the pathogenesis of urinary stone formation. The purpose of our study is to compare the incidence of the abnormal metabolic stone risk factors between the calcium stone former with papillary calcification and the calcium stone former without papillary calcification on unenhanced spiral computed tomography (CT). MATERIALS AND METHODS: A series of patients with calcium stones (n=49) underwent unenhanced spiral CT and complete metabolic evaluation after they consumed a random diet for 1 month after stone removal. Of the 49 patients, 38 patients showed papillary calcification on unenhanced spiral CT and 11 patients did not. Their blood was evaluated by using a multichannel analysis sequential multichannel autoanalyzer (SMA)-20 and PTH tests. The 24-hour urinary constituents were assayed for calcium, oxalate, citrate, total volume, phosphorus and sodium. We compared the incidence of abnormal metabolic risk factors between the two groups. Statistical analysis was performed by chi-square tests. RESULTS: The incidences of hyperuricemia were 27.3% in the patients without papillary calcification and 31.6% in the patients with papillary calcification. The incidences of hypernatriuria were 18.2% versus 42.1%, the incidences of hypercalciuria were 36.4% versus 26.3%, the incidences of hyperuricosuria were 18.2% versus 18.4%, the incidences of hyperoxaluria were zero versus 28.9%, and the incidences of hypocitraturia were 45.5% versus 44.7%, respectively. The difference between the two groups was statistically significant only for hyperoxaluria (p=0.043). CONCLUSIONS: Hyperoxaluria is the only metabolic risk factor that more frequently occurred in the patients with papillary calcification. Our date suggest that hyperoxaluria may be an important factor in the pathogenesis of papillary calcification.