BACKGROUND: The presence of \"muddy\" brown granular casts (MBGC) in the urine sediment is pathognomonic for acute tubular injury (ATI). Although MBGC have been noted for years, there are no reports regarding their length nor width. The objective of this study was to measure MBGC using images obtained by light microscopy and investigate associations with clinically relevant parameters.
METHODS: Patients with diagnosis of ATI as evidenced by visualization of abundant MBGC (>30% low power fields) were sampled. Bright-field images were measured using ImageJ. Twenty-five patients were included: 44% women; median age 64 yrs; 52% white, 36% black. Mean MBGC width (n = 350) was 34.4 ± 13.1 µm (range: 9 to 110 µm).
RESULTS: Mean MBGC length was 98.7 ± 42.7 µm (range: 33 to 317 µm). Based on a previous report of cortical tubular diameters, MBGC width corresponded well with the median reported range. MBGC width was positively correlated with patient height (ρ=0.41, p=0.04), and length was positively correlated with fractional excretion of sodium (ρ=0.57. p=0.02) and urine chloride concentration (ρ=0.90, p=0.001). Mean MBGC length was negatively correlated with age (ρ=-0.47, p=0.02) and urine phosphate concentration (ρ=-0.72, p=0.03). There were no differences between cases that required renal replacement therapy (RRT, n =10) and those that did not require RRT (n=15).
CONCLUSIONS: This is the first study reporting dimensions of MBGC from cases with ATI. Clinical implications of these observations require further study.

UNASSIGNED: Patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) usually present with multisystemic dysfunction with a wide range of clinical manifestations. When the tests for common mitochondrial DNA (mtDNA) point mutations are negative and the mtDNA defects hypothesis remains, urine epithelial cells can be used to screen the mitochondrial genome for unknown mutations to confirm the diagnosis.
UNASSIGNED: A 66-year-old Chinese woman presented with symptoms of MELAS and was initially misdiagnosed with acute encephalitis at another institution. Although genetic analysis of blood lymphocyte DNA was negative, brain imaging, including magnetic resonance imaging, magnetic resonance spectroscopy, and clinical and laboratory findings, were all suggestive of MELAS. Finally, the patient was eventually diagnosed with MELAS with the mtDNA 5783G>A mutation in the MT-TC gene with a urinary sediment genetic test.
UNASSIGNED: This case report expands the genetic repertoire associated with MELAS syndrome and highlights the importance that full mtDNA sequencing should be warranted beside the analysis of classical variants when a mitochondrial disorder is highly suspected. Furthermore, urine sediment genetic testing has played a crucial role in the diagnosis of MELAS.

Renal involvement is very common in patients with HIV infection. The phenotype varies from the most frequently \"collapsing\" variant of focal and segmental glomerulosclerosis (FSGS) to \"lupus-like HIV-immune complex kidney disease\" (HIVICK). The latter is characterized by a histological picture that recalls lupus nephropathy. Through a clinical case, we underline the importance of urinary sediment analysis in patients with suspected glomerulopathy. Findings such as the characteristic cells that show the typical appearance of Herpes virus (HSV) infection or LE cells have significantly supported the diagnosis of HIVICK. In light of the present observations, we suggest systematically carrying out a cytological examination of the urinary sediment to confirm diagnostic hypotheses of rare pathologies.

Renal biopsy is the gold standard for making the final diagnosis and for predicting the progression of renal disease, but monitoring disease status by performing biopsies repeatedly is impossible because it is an invasive procedure. Urine tests are non-invasive and may reflect the general condition of the whole kidney better than renal biopsy results. We therefore investigated the diagnostic value of extensive urinary sediment analysis by immunofluorescence staining for markers expressed on kidney-derived cells (cytokeratin: marker for tubular epithelial cells, synaptopodin: marker for podocytes, claudin1: marker for parietal epithelial cells, CD68: marker for macrophages (MΦ), neutrophil elastase: marker for neutrophils). We further examined the expression levels of the mRNAs for these markers by real-time reverse transcription polymerase chain reaction. We also examined the levels of mRNAs associated with the M1 (iNOS, IL-6) and M2 (CD163, CD204, CD206, IL-10) MΦ phenotypes. Evaluated markers were compared with clinical and histological findings for the assessment of renal diseases. Claudin1- and CD68-positive cell counts in urinary sediments were higher in patients with glomerular crescents (especially cellular crescents) than in patients without crescents. The relative levels of mRNA for CD68 and the M2 MΦ markers (CD163, CD204, CD206, and IL-10) in urinary sediments were also higher in patients with glomerular crescents. These data suggest that immunofluorescence staining for claudin1 and CD68 in urinary sediments and the relative levels of mRNA for CD68 and M2 MΦ markers in urinary sediments are useful for evaluating the state of glomerular diseases.

BACKGROUND: Urinary bladder cancer (UBC) is the most common malignancy affecting the urinary system. This study aimed to investigate the diagnostic value of combining DAPK methylation in urinary sediment and B ultrasound in the detection of recurrent UBC.
METHODS: A total of 1021 cases with primary UBC who underwent electrocision of bladder tumor through urethra were included in this study and followed up. Various parameters including B ultrasound, DAPK methylation in urinary sediment, examination of exfoliated cells in the urine, and cystoscopy were performed. The data collected was analyzed using the Kappa test, and receiver operating characteristic (ROC) curve was constructed to assess the diagnostic role in recurrent UBC.
RESULTS: Among the 1021 patients, 115 patients experienced recurrence confirmed by cystoscopy and biopsy within two years and were excluded from the study, resulting in an effective sample size of 906 primary UBC cases. The results of cystoscopy showed agreement with B ultrasound (Kappa = 0.785, P < 0.05), as well as with DAPK methylation in urinary sediment, and the combination of B ultrasound and DAPK methylation (Kappa = 0.517, P < 0.05, Kappa = 0.593, P < 0.05). The combination of B ultrasound with DAPK methylation yielded an area under the curve of 0.922, with a sensitivity of 92.86%, specificity of 91.63%, and a negative predictive value of 99.4%, suggesting that a negative result indicates a low risk of recurrence.
CONCLUSIONS: The combination of DAPK methylation in urinary sediment with B ultrasound demonstrates high diagnostic performance for recurrent UBC.

BACKGROUND: Accumulating evidence has confirmed the role of snoRNAs in a variety of cancer, but rare in renal cell carcinoma (RCC). This study aims to clarify the role of snoRNAs in RCC tumorigenesis and their potential as novel tumor biomarkers.
METHODS: The snoRNA expression matrix was obtained from the public TCGA and SNORic databases. SNORD15A, SNORD35B and SNORD60 were selected and validated by qPCR, then analyzed combined with related clinical factors using T-test and ROC curve.
RESULTS: All three snoRNAs: SNORD15A, SNORD35B and SNORD60 were significantly upregulated in cancer tissues compared to adjacent tissues from TCGA or FFPE detection. These three snoRNAs were also increased in urinary sediment (US) of RCC as well as the early-stage RCC patients compared with the healthy controls. In addition, RNase stability experiments confirmed their stable existence in US. Meanwhile, the ROC curve shows that SNORD15A, SNORD35B and SNORD60 could effectively distinguish RCC (AUC = 0.7421) and early-stage RCC (AUC = 0.7465) from healthy individuals.
CONCLUSIONS: SNORD15A, SNORD35B and SNORD60 were upregulated in tissues and US of RCC, serving as novel potential biomarkers for RCC diagnosis.

In this article we describe a case of acute kidney injury caused by ethylene glycol intoxication which partially reversed after temporary hemodialysis treatment. The diagnosis was obtained after the patient\'s clinical history and the finding of ethylene glycol in the blood, numerous intratubular crystals at renal biopsy, and the presence of large amounts of atypical - spindle-like and needle-like - calcium oxalate crystals in the urinary sediment.

Although casts in urine may imply the underlying pathogenesis and the diagnosis, the waxy cast is poorly understood yet. We aim to investigate the association between waxy casts and clinicopathological indices. Patients undergone renal biopsy and urine sediment examination were enrolled. Waxy casts referred to those presented with a homogeneous melted wax appearance and pre-waxy casts referred to those in which one or more segments demonstrated a waxy-cast appearance. Multivariable logistic regression was used to assess the factors associated with waxy casts. In 1282 patients, the detection rate of waxy casts was 26.3%. If either waxy or pre-waxy cast was considered as a diagnostic marker for renal insufficiency (eGFR < 60 ml/min/1.73 m2), the sensitivity was 0.58 and the specificity was 0.88. If the only waxy cast was considered as the diagnostic marker, the sensitivity was 0.29 and the specificity was 0.97. The patients with waxy or pre-waxy casts had higher blood pressure, more proteinuria, and worse renal function. Waxy or pre-waxy cast was independently associated with eGFR (odds ratio: 0.73 per 10 mL/min/1.73 m2 increase, 95% confidence interval: 0.69-0.77, p < 0.001), proteinuria (odds ratio: 1.07 per 1 g/day increase, 95% confidence interval: 1.03-1.10, p < 0.001) and pathological lesions. Waxy or pre-waxy casts are closely related to impaired renal function. Their presence is a specific indicator of renal insufficiency but is not sensitive enough.

The examination of the urinary sediment of a kidney transplant recipient, carried out in blind conditions, showed the presence of a moderate number of cells which were identified as decoy cells. Most frequently these cells are a marker of BK polyomavirus reactivation, which can lead to BK virus nephropathy and graft loss. However, the patient\'s clinical history, the absence of BK viremia, and the renal biopsy findings excluded this condition. The careful examination of the renal biopsy demonstrated a severe tubular damage with cells resembling those identified in the urine as decoy cells. This paper is the first which demonstrates that damaged renal tubular epithelial cells can be misidentified as decoy cells. In addition, it highlights the importance of supplying adequate clinical information for a correct urinary sediment examination.

The internalization of apoptotic cells by non-phagocytic cells has been observed in different tissues and could be an important mechanism for the elimination of dying cells. Here, we describe a probable event of phagocytosis of apoptotic cells mediated by urothelial cells in urinary sediment. A 90-years-old male patient was admitted unconscious to the hospital, visible signs included: pale skin and dry mucous membranes, presumptively diagnosed as dehydration. Blood test revealed anaemia (haemoglobin 130 g/L) and hyperglycaemia (glucose 7.8 mmol/L), urinalysis showed a picture of urinary tract infection (leukocyturia and bacteriuria). The microscopic analysis of urinary sediment revealed the presence of urothelial cells and leukocytes internalized in urothelial cells. Anti-CD68 (membrane marker of macrophages) was tested by immunocytochemistry and a negative result was observed. Based on the findings phagocytosis of apoptotic cells mediated by urothelial cells was identified. This phenomenon can be observed in urinary sediment and should not be confused with a neoplastic process since it is a physiological event of cell elimination.