1400W Prevents Renal Injury in the Renal Cortex But Not in the Medulla in a Murine Model of Ischemia and Reperfusion Injury.

BACKGROUND/AIMS: Acute kidney injury (AKI) carries high morbidity and mortality, and the inducible nitric oxide synthase (iNOS) is a potential molecular target to prevent kidney dysfunction. In previous work, we reported that the pharmacological inhibitions of iNOS before ischemia/reperfusion (I/R) attenuate the I/R-induced AKI in mice. Here, we study the iNOS inhibitor 1400W [N-(3-(Aminomethyl)benzyl] acetamide, which has been described to be much more specific to iNOS inhibition than other compounds. METHODS: We used 30 minutes of bilateral renal ischemia, followed by 24 hours of reperfusion in Balb/c mice. 1400w (10 mg/kg i.p) was applied before I/R injury. We measured the expression of elements associated with kidney injury, inflammation, macrophage polarization, mesenchymal transition, and nephrogenic genes by qRT-PCR in the renal cortex and medulla. The Periodic Acid-Schiff (PAS) was used to study the kidney morphology. RESULTS: Remarkably, we found that 1400W affects the renal cortex and medulla in different ways. Thus, in the renal cortex, 1400W prevented the I/R-upregulation of 1. NGAL, Clusterin, and signs of morphological damage; 2. IL-6 and TNF-α; 3. TGF-ß; 4. M2(Arg1, Erg2, cMyc) and M1(CD38, Fpr2) macrophage polarization makers; and 5. Vimentin and FGF2 levels but not in the renal medulla. CONCLUSION: 1400W conferred protection in the kidney cortex compared to the kidney medulla. The present investigation provides relevant information to understand the opportunity to use 1400W as a therapeutic approach in AKI treatment.

[Association of COVID-19 and glomerulonephritis with ANCA and anti-glomerular basement membrane antibodies. Report of one case]. / COVID-19, glomerulonefritis ANCA y anti-membrana basal glomerular. Caso clínico.

Renal involvement in COVID-19 infection is varied and worsens its outcome and prognosis. However, the association of COVID-19 infection with glomerulonephritis is exceptional. We report a 46-year-old woman with COVID-19 who had an acute kidney injury and ANCA associated glomerulonephritis two weeks after the onset of the disease. The kidney biopsy showed a crescentic glomerulo-nephritis and the presence of anti-glomerular basement membrane antibodies (GBM-Abs). She was treated with steroids and oral cyclophosphamide with good response without requiring plasmapheresis. Plasma anti GBM-Abs were negative. This case suggests that the presence of anti-GBM-Abs in the kidney, was temporally related to COVID-19 pulmonary damage. The absence of plasma antibodies is probably due to transient production and glomerular adsorption, but with unknown pathogenic role.

Diagnosis of light chain cast nephropathy through immunostaining of the urine: Perfecting the "liquid biopsy".

Light chain (LC) cast nephropathy is the main cause of kidney injury and an important determinant of poor survival in patients with multiple myeloma (MM). It is usually suspected when an MM patient with elevated serum concentration of free LC presents kidney failure, but it often requires confirmation by kidney biopsy. We report the case of a 73-year-old woman who presented with fatigue, weight loss, and constipation. Laboratory exams revealed anemia, hypercalcemia, and kidney failure. Urine sediment analysis demonstrated irregular crystalline "waxy type" casts. With the hypothesis of LC cast nephropathy, immunostaining of the urine sediment was performed. The analysis revealed several rectangular and irregular casts with intense and bright stain for λ LCs only. A myelogram was performed, showing extensive occupation of the bone marrow by plasma cells; and immunofixation in urine and serum revealed monoclonal IgG-λ component, confirming the diagnosis of IgG-λ MM. This case highlights the potential utility of the urine sediment analysis and immuno-staining as a reliable non-invasive alternative method for diagnosis of cast nephropathy in patients with monoclonal gammopathies.

Bladder squamous cell carcinoma in a pregnant woman: case report and review of the literature.

BACKGROUND: Bladder tumors in pregnancy are extremely rare. No more than 50 cases have been published to date, including all histologic variants, and only three cases of bladder squamous cell carcinoma have been described. CASE PRESENTATION: We present a clinical case of a 31-year-old woman with bladder squamous cell carcinoma in the second trimester of pregnancy. After a C-section at 30 weeks, we performed radical cystectomy with extended bilateral lymphadenectomy, hysterectomy and right oophorectomy. The Studer neobladder technique was performed for urinary tract reconstruction. Definitive pathology showed invasive bladder squamous cell carcinoma, Grade 2, with microscopic infiltration of the perivesical fat, negative margins, and 3/28 lymph nodes with carcinoma (pT3aN2M0). The patient underwent 18 months of surveillance after radical cystectomy, without recurrence by PET-CT. CONCLUSIONS: Bladder cancer in pregnant women is extremely rare but must be considered in those with recurrent gross hematuria and/or recurrent urinary tract infection. To our knowledge, this case involves the longest recurrence-free survival of a pregnant woman with squamous cell bladder cancer published thus far.

[Acute phosphate nephropathy secondary to the use of oral sodium phosphate laxatives. Report of one case]. / Nefropatía aguda por fosfatos secundaria al uso de laxantes con fosfato de sodio: caso clínico-patológico.

Acute phosphate nephropathy (APN) is an acute renal failure secondary to the use of oral sodium phosphate (OSP) laxatives, with a high risk of progression to chronicity. We report a 60-year-old woman with mixed connective tissue disease whose serum creatinine increased up to 2.0 mg/dL in her regular control tests, without an evident causative factor. Kidney biopsy showed numerous intratubular calcium phosphate deposits, consistent with APN. She had a history of OSP laxative intake, and a sodium phosphate enema was used before a colonoscopy performed six months earlier. The temporal association between the use of OSP laxatives and acute kidney injury, should lead to the suspicion of APN. The urine sediment is generally normal or with mild to moderate proteinuria. The diagnosis is confirmed with a kidney biopsy. Until now, there is no specific treatment for APN, thus prevention is essential. In high-risk patients for developing APN, the administration of these laxatives should be avoided.

Epidemiological and clinical characteristics and outcome of monoclonal gammopathy of renal significance-related lesions in Latin America.

BACKGROUND: Monoclonal gammopathy of renal significance (MGRS)-related lesions are infrequent entities. There are no publications on these disorders in Latin America (LA). The aim of this study was to describe epidemiological and clinical characteristics of these patients in LA. METHODS: We performed a multicentre retrospective study. Patients with diagnosis of MGRS between 2012 and 2018 were included. Epidemiological and clinical data were collected from clinical records. RESULTS: Twenty-seven patients from Chile, Argentina, Ecuador and Uruguay were included. Half debuted with a nephrotic syndrome, and 32% required dialysis. Proliferative glomerulonephritis with monoclonal immunoglobulin deposits was found in 33%, amyloidosis in 26% and monoclonal immunoglobulin deposition disease also in 26%. The immunoglobulin most frequently found in renal biopsies was IgG kappa. In 67% a paraprotein was found. Twenty patients received an anti-plasma cell regimen, and 3 a rituximab-based regimen (IgM-MGRS). Renal response (RR) was achieved in 56%. Early treatment (≤3 months) was associated with higher RR (75% vs 43%). Three patients relapsed within 21.5 months, and 3 progressed: 1 to multiple myeloma, 1 to systemic amyloidosis and another to systemic light-chain deposition disease. Two patients died, both due to infection during induction treatment. CONCLUSION: There was a higher than expected frequency of patients requiring dialysis. The most common MGRS-related lesion was PGNMD. Early treatment was associated with better response. As a rare disease, increasing awareness and promoting early diagnosis are necessary in LA to improve outcomes. SUMMARY AT A GLANCE A collection of 27 cases of MGRS from Latin America with information on epidemiology, clinical characteristics, treatment and outcome of patients diagnosed of MGRS-related renal lesions.

[C1q nephropathy. Report of one case]. / Nefropatía por C1q: una rara variedad de síndrome nefrótico. Caso clínico.

C1q nephropathy is a rare glomerulopathy characterized by mesangial deposition of the complement component C1q. These deposits can be isolated or associated with immunoglobulins or complement fractions, which are observed by immunofluorescence or immunohistochemical microscopy. In ultramicroscopy, dense mesangial deposits and alterations of the podocyte are observed. Clinically it presents as a nephrotic syndrome (NS) or by alterations of the urinalysis such as proteinuria and/or hematuria in children and young adults. In light microscopy, it is expressed with a morphological pattern of minimal change disease (MCD), mesangial proliferative glomerulonephritis or focal segmental glomerulosclerosis (FSGS). The NS during its evolution usually evolve in steroid resistance or steroid dependency, often requiring the association of immunosuppressants to obtain remission. We report a 14 years old male with a history of NS and its evolution under various treatments during a 12-year follow-up.

[Paraprotein-related kidney disease. Experience in 22 cases]. / Nefropatías secundarias a paraproteína: perfil clínico a partir de hallazgos histológicos.

BACKGROUND: One of the devastating consequences of monoclonal gammopathies is the development of end-stage kidney disease, which can be prevented with an early diagnosis. Renal involvement can be secondary to saturation of paraproteins with intratubular precipitation or the glomerular deposition of paraproteins with secondary inflammation and destruction. These conditions can also be associated with monoclonal gammopathies that do not meet hematological treatment criteria, called monoclonal gammopathies of renal significance (MGRS). AIM: To report a retrospective analysis of patients who underwent a renal biopsy and whose final diagnosis was a form of monoclonal gammopathy. MATERIAL AND METHODS: We reviewed the clinical and laboratory features and response to treatment of 22 patients aged 63 ± 12 years (55% women) with a pathological diagnosis of a nephropathy associated with paraproteinemia. RESULTS: The most common hematological diagnosis was amyloidosis in 50% of patients, followed by cast nephropathy. The predominant clinical presentations were proteinuria (without nephrotic syndrome) and nephritic syndrome. Classic criteria such as erythrocyte sedimentation rate > 100 mm/h and protein-albumin gap were unusual. Serum light chain quantification was the test with the best yield to detect paraproteins. CONCLUSIONS: In this group of patients, light chains tend to affect the kidney more commonly than heavy chains. The prognosis of multiple myeloma is much worse than MGRS.

[Clinicopathological correlation among proliferative classes and subclasses of lupus nephritis in renal biopsies]. / Correlación anátomo-clínica entre clases y subclases roliferativas de nefritis lúpica en biopsias renales: experiencia de un centro único.

Background Lupus nephritis (LN) is a complication of systemic lupus erythematosus that requires renal biopsy (RB). Proliferative classes III, IV-S, IV-G have especial clinical and pathological characteristics. Aim To determine the association between pathological features in RB with serum creatinine and urine protein levels. Material and Methods We analyzed 186 RB performed in adults aged 18 to 73 years, from a renal pathology reference center. Histopathological variables such as class and subclass of proliferative LN, endocapillary and extracapillary proliferation, activity and chronicity indexes, and vascular sclerosis were correlated with serum creatinine and urine protein levels, at the time of diagnosis. Results As compared with LN III, all the morphological and laboratory values were significantly more deteriorated in LN IV, with special focus on vascular sclerosis. Serum creatinine was the only variable that significantly differentiated LN IV-S from LN IV-G. Proteinuria was non-significantly higher in LN IV-G compared to LN IV-S. However, the difference became significant when proteinuria was compared between LN IV-G and LN III. Conclusions The significant difference in serum creatinine between LN IV-S and LN IV-G supports the concept that they are different subclasses. Proteinuria is a variable that differentiates classes III from IV-G, being significantly higher in the second. Severe arteriosclerosis is a constant and significant finding that differentiates LN III from LN IV. Thus, we propose its usefulness for distinguishing LN classes, and eventually, to be considered in the chronicity index.

[Recurrence of goodpasture syndrome with negative antiglomerular basement antibodies. Report of one case]. / Recurrencia de Síndrome de Goodpasture con negativización de anticuerpos anti-membrana basal glomerular: Caso clínico.

Goodpasture Syndrome is described as a single episode disease entity. It is diagnosed with the demonstration of antiglomerular basement (anti-GBM) antibodies in plasma or renal tissue. Although the recurrence of anti-GBM disease is rare, it has been reported in up to 3% of cases. Recurrence with negative anti-GBM antibodies in plasma is even less frequent We report a 63 years old male in whom anti-GBM disease recurred without detectable anti-GBM antibodies in plasma, despite having positive antibodies at the onset.

[Hypophysitis and retroperitoneal fibrosis associated with autoimmune polyglandular syndrome and IgG4-related disease. Report of one case]. / Hipofisitis linfoplasmocitaria y fibrosis retroperitoneal asociadas a un síndrome poliglandular autoinmune. Enfermedades relacionadas con IgG4. Caso clínico.

We report a 23 year old woman presenting with a nephrotic syndrome due to minimal change disease, central diabetes insipidus, primary hypothyroidism, vitiligo and universal alopecia. Eleven years later, she presented secondary amenorrhea due to hypogonadotropic hypogonadism, with mild hyperprolactinemia and central adrenal insufficiency. A magnetic resonance imaging of the sella turcica showed a pituitary mass with suprasellar extension that was resected using a transsphenoidal approach. Pathology confirmed the presence of a lymphoplasmacytic hypophysitis. She needed a second surgical resection due to mass growth and neuro-ophthalmologic impairment. One year later, systemic lupus erythematosus, arterial hypertension and type 2 diabetes mellitus were diagnosed. Two years later, due to back pain, constipation and renal failure, retroperitoneal fibrosis was found, satisfactorily treated with glucocorticoids and colchicine. Hence, this clinical vignette shows the coexistence of autoimmune polyglandular syndrome with retroperitoneal fibrosis and lymphoplasmacytic hypophysitis. Tissue analysis showed the presence of IgG4 producing plasma cells in the pituitary and retroperitoneum, which constitute a basis for the diagnosis of IgG4 related disease.

[Renal involvement in antineutrophil cytoplasmic antibodies (ANCA) associated vasculitides. Recommendations of the Chilean Societies of Nephrology and Rheumatology]. / Compromiso renal en vasculitis asociadas a anticuerpos anticitoplasma de neutrófilos. Recomendaciones de consenso de las Sociedades Chilenas de Nefrología y Reumatología.

Renal involvement is a frequent complication in antineutrophil cytoplasmic antibodies (ANCA)associated vasculitides, adding morbidity and mortality, such as chronic kidney disease and the need for renal replacement therapy. With the aim of reaching a consensus on relevant issues regarding the diagnosis, treatment and follow-up of patients with these diseases, the Chilean Societies of Nephrology and Rheumatology formed a working group that, based on a critical review of the available literature and their experience, raised and answered consensually a set of questions relevant to the subject. This document includes aspects related to the clinical diagnosis, the histological characteristics, the therapeutic alternatives to induce and maintain the remission of the disease, relapse surveillance strategies and complementary therapies.

[IgG4 associated nephritis and recurrent hemoptysis: Case report]. / Hemoptisis recurrente asociada a falla renal y hematuria: otra de las mil caras de la enfermedad relacionada a IgG4.

IgG4 disease is a multi-systemic condition involving pancreas, salivary glands and lymph nodes. Less frequently, it causes interstitial nephritis and involves the lungs. We report a 58 years old male with a four years history of hemoptysis and renal dysfunction characterized by hematuria and proteinuria, responsive to steroidal therapy. The renal biopsy established the diagnosis of IgG4 associated interstitial nephritis. Lung involvement was considered secondary to the same systemic disease.

Human metapneumovirus infection activates the TSLP pathway that drives excessive pulmonary inflammation and viral replication in mice.

Human metapneumovirus (hMPV) is a leading cause of acute respiratory tract infections in children and the elderly. The mechanism by which this virus triggers an inflammatory response still remains unknown. Here, we evaluated whether the thymic stromal lymphopoietin (TSLP) pathway contributes to lung inflammation upon hMPV infection. We found that hMPV infection promotes TSLP expression both in human airway epithelial cells and in the mouse lung. hMPV infection induced lung infiltration of OX40L(+) CD11b(+) DCs. Mice lacking the TSLP receptor deficient mice (tslpr(-/-) ) showed reduced lung inflammation and hMPV replication. These mice displayed a decreased number of neutrophils as well a reduction in levels of thymus and activation-regulated chemokine/CCL17, IL-5, IL-13, and TNF-α in the airways upon hMPV infection. Furthermore, a higher frequency of CD4(+) and CD8(+) T cells was found in tslpr(-/-) mice compared to WT mice, which could contribute to controlling viral spread. Depletion of neutrophils in WT and tslpr(-/-) mice decreased inflammation and hMPV replication. Remarkably, blockage of TSLP or OX40L with specific Abs reduced lung inflammation and viral replication following hMPV challenge in mice. Altogether, these results suggest that activation of the TSLP pathway is pivotal in the development of pulmonary pathology and pulmonary hMPV replication.

[Antineutrophil cytoplasmic antibody (ANCA) associated renal vasculitis and pregnancy: Report of one case]. / Evolución de una vasculitis renal asociada a anticuerpos anti-citoplasma de neutrófilos (ANCA) durante un embarazo: Caso clínico.

ANCA mediated vasculitis mainly occur between the fourth and fifth decade of life; therefore, it is very uncommon to see pregnant patients with the disease. Vasculitis may affect significantly the course of pregnancy; in turn pregnancy can change the course of vasculitis. We report a 20 years old woman with ANCA-mediated renal vasculitis lasting 10 years who consulted with a pregnancy of 15 weeks. She was in remission and had amenorrhea attributed to ovarian toxicity due to cyclophosphamide. Pregnancy had an uneventful course with spontaneous delivery at the 37th week, giving birth to a healthy newborn. Proteinuria increased during the course of pregnancy with a mild deterioration of kidney function. During the year after delivery, she had nephrotic proteinuria and a worsening of renal function.

[Ultrastructural alterations in renal biopsy leading to the diagnosis of HIV infection]. / Diagnóstico de infección por VIH por el hallazgo incidental de alteraciones ultraestructurales en una biopsia renal: Report of one case.

HIV infection has different clinical presentations. We report a 21-year-old male with longstanding isolated microscopic hematuria attributed to thin glomerular basement membrane disease, who after 15 years of follow-up presented with significant proteinuria. A kidney biopsy was performed, revealing the presence of tubulo-reticular inclusions in the glomerular endothelial cells. This finding led to suspect an HIV infection, which was verified. Antiretroviral therapy, angiotensin-converting enzyme and angiotensin II receptor blockers were prescribed. At 6 years of diagnosis the patient is asymptomatic and has normal kidney function. Microscopic hematuria and low level proteinuria persists.

Relapsing nephrotic syndrome with acute renal failure following a unique episode of multiple bee stings: A case report.

The commonest renal involvement after bee stings is acute kidney injury due to rhabdomyolysis. Nephrotic syndrome combined with AKI is unusual complication of Hymenoptera stings. We diagnosed a minimal change disease and six-year follow up relapses.

Galectin-8 counteracts folic acid-induced acute kidney injury and prevents its transition to fibrosis.

Acute kidney injury (AKI), characterized by a sudden decline in kidney function involving tubular damage and epithelial cell death, can lead to progressive tissue fibrosis and chronic kidney disease due to interstitial fibroblast activation and tissue repair failures that lack direct treatments. After an AKI episode, surviving renal tubular cells undergo cycles of dedifferentiation, proliferation and redifferentiation while fibroblast activity increases and then declines to avoid an exaggerated extracellular matrix deposition. Appropriate tissue recovery versus pathogenic fibrotic progression depends on fine-tuning all these processes. Identifying endogenous factors able to affect any of them may offer new therapeutic opportunities to improve AKI outcomes. Galectin-8 (Gal-8) is an endogenous carbohydrate-binding protein that is secreted through an unconventional mechanism, binds to glycosylated proteins at the cell surface and modifies various cellular activities, including cell proliferation and survival against stress conditions. Here, using a mouse model of AKI induced by folic acid, we show that pre-treatment with Gal-8 protects against cell death, promotes epithelial cell redifferentiation and improves renal function. In addition, Gal-8 decreases fibroblast activation, resulting in less expression of fibrotic genes. Gal-8 added after AKI induction is also effective in maintaining renal function against damage, improving epithelial cell survival. The ability to protect kidneys from injury during both pre- and post-treatments, coupled with its anti-fibrotic effect, highlights Gal-8 as an endogenous factor to be considered in therapeutic strategies aimed at improving renal function and mitigating chronic pathogenic progression.

[Hemolytic-uremic syndrome associated with gemcitabine use: report of one case]. / Síndrome hemolítico-urémico asociado al uso de gemcitabina: Caso clínico.

Gemcitabine is a widely used drug in the treatment of advanced pancreatic cancer and other malignancies. It is generally well tolerated and exceptionally its use has been associated with hemolytic-uremic syndrome, causing acute kidney injury, hypertension, chronic renal failure requiring dialysis, and death. We report a 60-year-old man with pancreatic carcinoma and regional lymph node invasion, whom after four months of therapy with gemcitabine and after dose number 11, suddenly developed an acute nephritic syndrome with moderate renal impairment, associated with severe anemia (hemoglobin 6.0 g/dL) and thrombocytopenia (20,000 mm³). Renal biopsy showed the classic findings of thrombotic microangiopathy Gemcitabine was discontinued and renal function and hematological parameters gradually improved.