Visualization of intracellular ATP dynamics in different nephron segments under pathophysiological conditions using the kidney slice culture system.

ATP depletion plays a central role in the pathogenesis of kidney diseases. Recently, we reported spatiotemporal intracellular ATP dynamics during ischemia reperfusion (IR) using GO-ATeam2 mice systemically expressing an ATP biosensor. However, observation from the kidney surface did not allow visualization of deeper nephrons or accurate evaluation of ATP synthesis pathways. Here, we established a novel ATP imaging system using slice culture of GO-ATeam2 mouse kidneys, evaluated the ATP synthesis pathway, and analyzed intracellular ATP dynamics using an ex vivo IR-mimicking model and a cisplatin nephropathy model. Proximal tubules (PTs) were found to be strongly dependent on oxidative phosphorylation (OXPHOS) using the inhibitor oligomycin A, whereas podocytes relied on both OXPHOS and glycolysis using phloretin an active transport inhibitor of glucose. We also confirmed that an ex vivo IR-mimicking model could recapitulate ATP dynamics in vivo; ATP recovery in PTs after reoxygenation varied depending on anoxic time length, whereas ATP in distal tubules (DTs) recovered well even after long-term anoxia. After cisplatin administration, ATP levels in PTs decreased first, followed by a decrease in DTs. An organic cation transporter 2 inhibitor, cimetidine, suppressed cisplatin uptake in kidney slices, leading to better ATP recovery in PTs, but not in DTs. Finally, we confirmed that a mitochondria protection reagent (Mitochonic Acid 5) delayed the cisplatin-induced ATP decrease in PTs. Thus, our novel system may provide new insights into the energy dynamics and pathogenesis of kidney disease.

Predominant CD8+ cell infiltration and low accumulation of regulatory T cells in immune checkpoint inhibitor-induced tubulointerstitial nephritis.

Immune checkpoint inhibitors (ICIs) can provide survival benefits to cancer patients; however, they sometimes result in the development of renal immune-related adverse events (irAEs). Tubulointerstitial nephritis (TIN) is the most representative pathological feature of renal irAEs. However, the clinicopathological entity and underlying pathogenesis of ICI-induced TIN are unclear. Therefore, we compared the clinical and histological features of this condition with those of non-ICI drug-induced TIN. Age and C-reactive protein levels were significantly higher in ICI-induced TIN, but there were no significant differences in renal function. Immunophenotyping of ICI-induced TIN showed massive T cell and macrophage infiltration with fewer B cells, plasma cells, neutrophils, and eosinophils. Compared with those in non-ICI drug-induced TIN, CD4+ cell numbers were significantly lower in ICI-induced TIN but CD8+ cell numbers were not significantly different. However, CD8/CD3 and CD8/CD4 ratios were higher in ICI-induced TIN. Moreover, CD25+ and FOXP3+ cells, namely regulatory T cells, were less abundant in ICI-induced TIN. In conclusion, T cell, B cell, plasma cell, neutrophil, and eosinophil numbers proved useful for differentiating ICI-induced and non-ICI drug-induced TIN. Furthermore, the predominant distribution of CD8+ cells and low accumulation of regulatory T cells might be associated with ICI-induced TIN development.

Development of angiogenic periglomerular microvessels after acute glomerular lesions in IgA nephropathy.

AIM: To clarify the clinicopathological characteristics and role of periglomerular angiogenesis in IgA nephropathy. METHODS AND RESULTS: The renal biopsy specimens of 114 patients with IgA nephropathy were examined. Among them, 46 (40%) showed periglomerular angiogenesis around the glomeruli. CD34 and α-smooth muscle actin (α-SMA) staining in serial sections revealed that these vessels contained CD34+ α-SMA+ microarterioles along with CD34+ α-SMA- capillaries. We termed these "periglomerular microvessels (PGMVs)". Patients with PGMVs (PGMV group) had clinically and histologically more severe disease than those without PGMVs (non-PGMV group) at the time of biopsy. Even after adjusting for age, there were significant differences in the degree of proteinuria and estimated glomerular filtration rate reduction between the PGMV and non-PGMV groups. The PGMV group showed a higher incidence of segmental and global glomerulosclerosis and crescentic lesions than the non-PGMV group (P < 0.01). Here, PGMVs were undetectable in the acute and active inflammation phase, but were observed in the acute to chronic or chronic glomerular remodelling phase. PGMVs mainly developed around glomerular adherent lesions to the Bowman's capsule with small or minimal glomerular sclerotic lesions. Conversely, they were rarely observed in segmental sclerosis areas. CONCLUSION: The PGMV group is clinically and pathologically more severe than the non-PGMV group; however, they were undetectable in segmental sclerosis with mesangial matrix accumulation. PGMVs might occur after acute/active glomerular lesions, suggesting that PGMVs may inhibit segmental glomerulosclerosis progression and could be a marker for good repair response after acute/active glomerular injury in severe IgA nephropathy cases.

Focal Segmental Sclerosis Associated with the Novel Multi-tyrosine Kinase Inhibitor Ponatinib.

Ponatinib is a novel multi-tyrosine kinase inhibitor (TKI) with potent inhibitory activity against refractory chronic myeloid leukemia (CML). Despite its high clinical efficacy, ponatinib induces various adverse events due to its multi-target characteristic. However, renal complications associated with ponatinib are rare. A 76-year-old woman had a history of chronic myeloid leukemia (CML) resistant to imatinib and nilotinib. Our patient developed proteinuria and renal function deterioration during treatment with ponatinib but not with imatinib or nilotinib. We herein report the first case of a patient with secondary focal segmental glomerulosclerosis (FSGS) with partial glomerular collapse induced by ponatinib treatment.

A possible role of classical complement pathway activation in the pathogenesis of immunoglobulin G nephropathy: a case report.

Immunoglobulin G (IgG) nephropathy refers to a rare group of diseases characterized by deposits of IgG in the mesangial region. However, IgG nephropathy is controversial as a single disease entity, and its pathogenesis remains to be elucidated. In the present report, we discuss a case of IgG nephropathy in which we observed activation of the classical complement pathway.A 47-year-old woman was admitted to our hospital with nephrotic syndrome. Light-microscopic examination revealed neither proliferative nor sclerotic lesions in the glomeruli. However, unusual and large deposits were observed in the paramesangial area. An immunofluorescence study revealed predominant IgG and C1q and slight C3 deposits in the paramesangial area, suggesting immune-complex-type glomerular disease. An electron microscopic study also revealed different sizes of non-organized electron-dense deposits with a similar pattern of distribution, which were accompanied by foot process effacement. Clinically, there was no evidence of systemic diseases, such as infectious or autoimmune diseases (including systemic lupus erythematosus). Based on these findings, she was diagnosed with IgG nephropathy and treated with prednisolone. Steroid therapy was effective, and complete remission was maintained.Additional immunological examination revealed that IgG deposits were polyclonal and consisted mainly of the IgG1 and IgG3 subclasses. Furthermore, staining was positive for C4d and C5b-9. The present findings indicate that the pathogenesis of IgG nephropathy in our patient may have involved activation of the classical complement pathway.

The reduced number of nephrons with shortening renal tubules in mouse postnatal adverse environment.

BACKGROUND: The intrauterine adverse environment during nephrogenesis reduces the nephron number, probably associates with impaired ureteric bud (UB) branching. METHODS: The kidneys in C57/BL6 mice were irradiated with a single dose of 10 gray (10 Gy) as adverse environment on postnatal day 3 (irradiated PND3 kidneys) after UB branching ceased. The renal functions and pathological findings of irradiated PND3 kidneys were compared with those of non-irradiated control and 10 Gy irradiation on PND14 (irradiated PND14 kidney) from 1 to 18 months. RESULTS: The number and density of glomeruli in irradiated PND3 kidneys were reduced by 1 month with renal dysfunction at 6 months. The morphologically incomplete glomeruli with insufficient capillaries were involuted by 1 month in the superficial cortex. Reduced tubular numbers and developmental disability with shortening renal tubules occurred in irradiated PND3 kidneys with impaired urine concentration at 6 months. Hypertrophy of glomeruli developed, and occasional sclerotic glomeruli appeared in the juxtamedullary cortex with hypertension and albuminuria at 12 to 18 months. CONCLUSIONS: The reduced number of nephrons with shortening renal tubules occurred with impaired renal functions in a postnatal adverse environment after cessation of UB branching, and glomerular hypertrophy with occasional glomerulosclerosis developed accompanied with hypertension and albuminuria in the adulthood. IMPACT: The reduced number of nephrons with shortening renal tubules occurred with impaired renal functions in a postnatal adverse environment after cessation of ureteric bud branching. The reduced number of glomeruli were associated with not only the impaired formation of glomeruli but also involution of morphologically small incomplete glomeruli after an adverse environment. The insufficiently developed nephrons were characterized by the shortening renal tubules with impaired urine concentration. In addition, glomerular hypertrophy and occasional glomerulosclerosis developed with hypertension and albuminuria in adulthood. The present study can help to understand the risk of alternations of premature nephrons in preterm neonates.

Diverse Alterations of Glomerular Capillary Networks in Focal Segmental Glomerular Sclerosis.

Introduction: Focal segmental glomerular sclerosis (FSGS) is caused by podocyte injury. It is characterized by obliteration of glomerular capillary tufts with increased extracellular matrix (ECM). Altered communication between podocytes and glomerular endothelial cells (ECs) contributes to sclerosis progression. We focused on EC injury in the FSGS. Methods: A total of 29 FSGS and 18 control biopsy specimens were assessed for clinicopathologic characteristics. CD34 (a marker for EC)-positive capillaries and ECM accumulation were evaluated quantitatively for each variant using computer-assisted image analysis. Results: The estimated glomerular filtration rate (eGFR) in the FSGS group was significantly lower than that in the control group. The frequency of FSGS variants was 51.7% for cellular; 13.8% for perihilar (PH), tip, and not otherwise specified (NOS); and 6.9% for collapsing. Regarding sclerotic lesions in all FSGS, narrowing or loss of CD34-positive capillaries was observed. Electron microscopy results showed loss of fenestrae, subendothelial space enlargement, and cytoplasmic swelling, indicating EC injury. Computer-assisted image analysis revealed significantly smaller areas of glomerular capillaries in FSGS with or without sclerotic lesions, with increased ECM. Moreover, in comparison with each variant, narrowed capillaries and ECM accumulation were most prominent in the collapsing variant, whereas the tip variant had the least change. Conclusion: EC injury was observed in all FSGS cases, not only in sclerotic lesions but also in nonsclerotic lesions. Severity of EC injury may vary in each variant due to diverse alterations of glomerular capillary networks.

Anti-neutrophil Cytoplasmic Antibody-associated Vasculitis Superimposed on Post-streptococcal Acute Glomerulonephritis.

A 44-year-old woman was admitted due to gross hematuria and progressive renal dysfunction. Poststreptococcal acute glomerulonephritis (PSAGN) was suspected due to her elevated anti-streptolysin O and anti-streptokinase titers and hypocomplementemia. A renal biopsy showed crescent formation and endocapillary hypercellularity with neutrophil infiltrate. An immunofluorescence analysis showed granular immunoglobulin G and C3 deposition, suggesting immune-complex-type glomerulonephritis. However, myeloperoxidase anti-neutrophil cytoplasmic antibody (ANCA) was positive, and peritubular capillaritis was observed. Furthermore, citrullinated histone H3-positive neutrophils were detected as markers for neutrophil extracellular trap formation. Therefore, she was diagnosed with ANCA-associated vasculitis superimposed on PSAGN that was the main contributor to her progressive renal injury.

A case of pathologically confirmed streptococcal infection-related IgA vasculitis with associated glomerulonephritis and leukocytoclastic cutaneous vasculitis.

We report the case of an 80 year-old woman who developed bilateral lower extremity purpura and renal impairment with proteinuria a few days after a transient fever (day 0). High levels of both anti-streptolysin-O antibody (ASO) and anti-streptokinase antibody (ASK), as well as low levels of coagulation factor XIII in serum were noted. Skin biopsy was performed and showed a leukocytoclastic vasculitis with deposition of IgA and C3 in the cutaneous small vessels, indicating IgA vasculitis in the skin. After initiation of oral prednisolone, the skin lesions showed significant improvement. However, renal function and proteinuria gradually worsened from day 12. Kidney biopsy was performed on day 29, which demonstrated a necrotizing and crescentic glomerulonephritis with mesangial deposition of IgA and C3. In addition, the deposition of galactose-deficient IgA1 (Gd-IgA1) was positive on glomeruli and cutaneous small vessels, indicating that the purpura and glomerulonephritis both shared the same Gd-IgA1-related pathogenesis. In addition, the association between the acute streptococcal infection and the IgA vasculitis was confirmed by the deposition of nephritis-associated plasmin receptor (NAPlr) in glomeruli. The patient was treated with steroid pulse and intravenous cyclophosphamide, in addition to the oral prednisolone treatment. Renal function and proteinuria gradually improved, but did not completely recover, as is typically seen with courses of IgA vasculitis in the elderly. In this case, the streptococcal infectionrelated IgA vasculitis was confirmed pathologically by the deposition of both NAPlr and Gd-IgA1 in glomeruli, as well as Gd-IgA1 in the cutaneous small vessels.

A case of proliferative glomerulonephritis with monoclonal IgG3κ deposits accompanied by glomerular capillary microaneurysms.

Glomerular capillary aneurysms are distinctly rare and specific glomerular lesions characterized by aneurysmal dilatation of the glomerular capillaries. This formation is associated with glomerular capillary injuries with focal mesangiolysis. Here, we report a case of proliferative glomerulonephritis with monoclonal immunoglobulin G deposits (PGNMID) presenting with multiple glomerular capillary microaneurysms. A 53-year-old woman presented with persistent proteinuria and microhematuria. She had no underlying diseases, such as hematopoietic or lymphoproliferative disorders. A renal biopsy showed diffuse membranoproliferative lesions with foam cell infiltration and multiple microaneurysms of the glomerular capillary on light microscopy. Immunofluorescence analysis showed granular deposits of monoclonal immunoglobulin G3 kappa (IgG3κ), C1q, C3, and C4 in the glomeruli. Electron microscopy revealed different sizes of non-organized electron-dense deposits in the mesangial, subendothelial, and subepithelial areas. In addition, glomerular endothelial cells showed swelling and loss of fenestra or diffuse formation of fenestrated diaphragms, accompanied by irregular thinning of the glomerular basement membrane. Furthermore, immunostaining for CD31 (a marker for endothelial cell) and low-vacuum scanning electron microscopy study identified loss of endothelial cells in microaneurysm, suggesting severe glomerular endothelial cell injury. After a renal biopsy, only the medication for dyslipidemia was continued because there were no physical symptoms, such as edema, and urinary abnormalities continued with stable renal function. Further studies are needed to elucidate the pathogenesis of glomerular capillary injury in PGNMID and clarify the clinical and pathological characteristics of PGNMID with glomerular capillary microaneurysms.

Evaluation of ultrastructural alterations of glomerular basement membrane and podocytes in glomeruli by low-vacuum scanning electron microscopy.

BACKGROUND: Low-vacuum scanning electron microscopy (LV-SEM) is applied to diagnostic renal pathology. METHODS: To demonstrate the usefulness of LV-SEM and to clarify the optimal conditions of pathology samples, we investigated the alterations of glomerular basement membrane (GBM) and podocytes in control and experimental active Heymann nephritis (AHN) rats by LV-SEM. RESULTS: On week 15 following induction of AHN, spike formation on GBM with diffuse deposition of IgG and C3 developed. Using LV-SEM, diffuse crater-like protrusions were clearly noted three-dimensionally (3D) on surface of GBM in the same specimens of light microscopy (LM) and immunofluorescence (IF) studies only after removal coverslips or further adding periodic acid-silver methenamine (PAM) staining. These 3D ultrastructural findings of GBM surface could be detected in PAM-stained specimens by LV-SEM, although true GBM surface findings could not be obtained in acellular glomeruli, because some subepithelial deposits remained on surface of GBM. Adequate thickness was 1.5-5 µm for 10% formalin-fixed paraffin-embedded (FFPE) and 5-10 µm for the unfixed frozen sections. The foot processes and their effacement of podocytes could be observed by LV-SEM using 10%FFPE specimens with platinum blue (Pt-blue) staining or double staining of PAM and Pt-blue. These findings were obtained more large areas in 2.5% glutaraldehyde-fixed paraffin-embedded (2.5%GFPE) specimens. CONCLUSION: Our findings suggest that LV-SEM is a useful assessment tool for evaluating the alterations of GBM and podocytes in renal pathology using routine LM and IF specimens, as well as 2.5%GFPE specimens.

The severity of glomerular endothelial cell injury is associated with infiltrating macrophage heterogeneity in endocapillary proliferative glomerulonephritis.

Endocapillary proliferation occurs in various types of glomerulonephritis (GN), with varying prognoses. We examined 42 renal biopsy samples representing endocapillary proliferative lesions from post-streptococcal acute GN (PSAGN), Henoch-Schönlein purpura nephritis (HSPN), and lupus nephritis (LN). In PSAGN, the glomerular capillary network was maintained, although severe lesions displayed dots or short, curved lines, indicating CD34-positive capillaries and suggesting capillary obstruction. Conversely, patients with LN and HSPN displayed obstruction of CD34-positive capillaries with dissociation from the glomerular basement membrane even in mild lesions. According to computer-assisted morphologic analysis, the cell density did not differ between the diseases. However, in PSAGN, the number of capillary loops was significantly increased, with a larger glomerular capillary luminal area than in the other groups. In addition, the number and frequency of CD163-positive cells (M2 macrophages) tended to be higher in PSAGN, while there were no significant differences in the number of CD68-positive (total) macrophages. These results indicate that in PSAGN, endothelial cell damage is less severe, and angiogenesis may be promoted. The severity of endothelial cell injury in each disease may be associated with differences in infiltrating inflammatory cell phenotypes.

A Case of Acute Kidney Injury Associated with Leriche Syndrome.

Leriche syndrome is an aortoiliac occlusive disease with three chief symptoms: claudication, impotence, and weak femoral pulse. It can also cause occlusion of the aorta up to the level of the renal arteries. We report a case in which aortoiliac bypass and renal artery thrombectomy were effective in ameliorating acute kidney injury caused by bilateral renal artery thrombosis.

Immunohistochemical detection of citrullinated histone H3-positive neutrophils is useful for identifying active glomerular and interstitial lesions in antineutrophil cytoplasmic antibody-associated vasculitis.

AIMS: Activated neutrophils release neutrophil extracellular traps (NETs), resulting in a form of cell death called NETosis. NET formation is reportedly involved in the onset of systemic lupus erythematosus and antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Citrullination of histones is a key step in NET formation, and the presence of citrullinated histones in neutrophils may be associated with disease induction and activity. The aim of this study was to investigate the relationship between infiltrating citrullinated histone H3 (H3Cit)-positive neutrophils and disease specificity and activity in various glomerulonephritides. METHODS AND RESULTS: We selected 32 kidney biopsies with glomerulonephritides, including AAV, lupus nephritis (LN), Henoch-Schönlein purpura nephritis (HSPN), and poststreptococcal acute glomerulonephritis (PSAGN). We examined the presence of H3Cit in infiltrating neutrophils and their association with necrotising, crescentic lesions and tubulointerstitial lesions. In PSAGN and HSPN, we found many myeloperoxidase (MPO)+ neutrophils in glomeruli; however, only a few were H3Cit+. In LN, MPO+ neutrophils mainly existed in the margins of glomerular tufts forming wire-loop lesions, and some of these were noted to be H3Cit+ neutrophils. In contrast, we found a significantly higher frequency of H3Cit+ neutrophils, despite the small number of MPO+ neutrophils, in microscopic polyangiitis in AAV. In particular, H3Cit+ neutrophils were prominent in necrotising lesions along the glomerular capillaries. Moreover, we also found H3Cit+ neutrophils in the interstitium, with marked peritubular capillaritis in AAV. CONCLUSIONS: H3Cit immunostaining is a useful tool for identifying activated neutrophils. The frequency of H3Cit+ neutrophils is not only a disease-specific marker but also a potential marker for disease activity in AAV.

Update on Recurrent Focal Segmental Glomerulosclerosis in Kidney Transplantation.

BACKGROUND: Focal segmental glomerulosclerosis (FSGS) is a clinicopathological syndrome characterized by nephrotic-range proteinuria with high incidence of progression to end-stage renal disease (ESRD). In primary FSGS, 40-60% of patients develop ESRD within 10-20 years. SUMMARY: Recurrence of FSGS after kidney transplantation is frequent and is associated with poor allograft survival. The risk factors for recurrent FSGS include onset of FSGS during childhood, rapid progression of primary FSGS to ESRD, history of recurrent FSGS in previous allograft, and diffuse mesangial hypercellularity or collapsing variant of FSGS in the native kidney. The early histological findings of recurrent FSGS consist of unremarkable glomerular changes on light microscopy but significant podocyte effacement on electron microscopy; the loss of foot processes with eventual dropout of podocytes leads to the development of segmental lesions in the glomerulus. Experimental and clinical data suggest the existence of circulating permeability factors, such as soluble urokinase-type plasminogen activator receptor (suPAR), cardiotrophin-like cytokine factor-1 (CLCF-1), CD40 axis, and apolipoprotein A-Ib (ApoA-Ib), in the pathogenesis of recurrent FSGS. These biomarkers including circulating permeability factors may facilitate earlier diagnosis of FSGS posttransplant and may guide in the development of novel therapies that may be more effective and improve long-term outcomes in kidney transplantation. Key Messages: Several studies have suggested the possible circulating permeability factors, such as suPAR, CLCF-1, CD40 axis, and ApoA-Ib, in the pathogenesis and disease progression of FSGS and recurrent FSGS. Further studies should be performed to elucidate the true essential biomarker(s) associated with the onset and progression of FSGS as well as recurrent FSGS.

Spatiotemporal ATP Dynamics during AKI Predict Renal Prognosis.

BACKGROUND: Depletion of ATP in renal tubular cells plays the central role in the pathogenesis of kidney diseases. Nevertheless, inability to visualize spatiotemporal in vivo ATP distribution and dynamics has hindered further analysis. METHODS: A novel mouse line systemically expressing an ATP biosensor (an ATP synthase subunit and two fluorophores) revealed spatiotemporal ATP dynamics at single-cell resolution during warm and cold ischemic reperfusion (IR) with two-photon microscopy. This experimental system enabled quantification of fibrosis 2 weeks after IR and assessment of the relationship between the ATP recovery in acute phase and fibrosis in chronic phase. RESULTS: Upon ischemia induction, the ATP levels of proximal tubule (PT) cells decreased to the nadir within a few minutes, whereas those of distal tubule (DT) cells decreased gradually up to 1 hour. Upon reperfusion, the recovery rate of ATP in PTs was slower with longer ischemia. In stark contrast, ATP in DTs was quickly rebounded irrespective of ischemia duration. Morphologic changes of mitochondria in the acute phase support the observation of different ATP dynamics in the two segments. Furthermore, slow and incomplete ATP recovery of PTs in the acute phase inversely correlated with fibrosis in the chronic phase. Ischemia under conditions of hypothermia resulted in more rapid and complete ATP recovery with less fibrosis, providing a proof of concept for use of hypothermia to protect kidney tissues. CONCLUSIONS: Visualizing spatiotemporal ATP dynamics during IR injury revealed higher sensitivity of PT cells to ischemia compared with DT cells in terms of energy metabolism. The ATP dynamics of PTs in AKI might provide prognostic information.

Risk Factors for Acute Kidney Injury and Chronic Kidney Disease following Allogeneic Hematopoietic Stem Cell Transplantation for Hematopoietic Malignancies.

BACKGROUND: Acute kidney injury (AKI) and chronic kidney disease (CKD) are considered common complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). OBJECTIVES AND METHOD: In this study, 114 patients who had undergone allo-HSCT were retrospectively analyzed to investigate the risk factors for onset of posttransplant AKI and CKD as defined by the new Kidney Disease Improving Global Outcomes criteria. RESULTS: Seventy-four patients (64.9%) developed AKI and 25 (21.9%) developed CKD. The multivariate analysis showed that the risk factors for developing stage 1 or higher AKI were age ≥46 years at the time of transplant (p = 0.001) and use of ≥3 nephrotoxic drugs (p = 0.036). For CKD, the associated risk factors were disease status other than complete remission at the time of transplantation (p = 0.018) and onset of AKI after transplant (p = 0.035). The 5-year overall survival (OS) was significantly reduced by development of AKI (p < 0.001), but not CKD. Posttransplant AKI significantly increased the 5-year nonrelapse mortality (p < 0.001), whereas posttransplant CKD showed an increasing tendency, but the difference was not significant. CONCLUSIONS: Posttransplant AKI impacts OS, significantly increases the risk of CKD, and is significantly associated with disseminated intravascular coagulation and use of ˃3 nephrotoxic drugs.