Renal biopsy in diabetic patients: clinical indicators and pathological findings / Biopsia renal en pacientes diabéticos: indicadores clínicos y hallazgos patológicos

ABSTRACT Background: In addition to diabetic nephropathies (DNP), prevalence of nondiabetic nephropathies (NDNP) is also known to be frequent in patients diagnosed with type 2 Diabetes mellitus (DM). Early diagnosis of these conditions is important for the treatment and prognosis of these patients. Aim: This study aimed to investigate the relationships between clinical and laboratory findings of type 2 diabetic patients' renal biopsies. Material and Methods: We retrospectively reviewed the medical records of 140 patients who had diagnosis of type 2 DM and underwent renal biopsy from July 2020- August 2022 at nephrology clinics of Hospital Umraniye. Renal biopsy results, presence of hypertension, diabetic retinopathy, hematuria, proteinuria; duration of the disease, biopsy indications, glycated hemoglobin (HbA1c), serum creatinine, blood urea nitrogen, albumin, and proteinuria levels in 24h urine were measured. The statistical significance level was determined as p<0,05. Results: NDNP were detected in 43,7% of the patients. Among these the most common diagnosis was interstitial nephritis (20%). The most common biopsy indication was found to be nephrotic range proteinuria (30,7%). The difference between the DNP and NDNP patients' renal biopsy indications was statistically significant (p<0,001). DNP patients had a higher retinopathy incidence (60%,11%, p<0,001). A statistically significant difference was detected between the disease duration of DNP and NDNP groups (11,23 +5,74 years, p:0,002). According to multivariate regression analysis DR and HbA1c value, more than 7% have 4, 482 and 4,591-fold increased the risk of DNP incidence (p=0,021, p:0,024). Conclusion: Early diagnosis of DNP and NDNP of diabetic patients by performing renal biopsies affects the treatment and prognosis of the patients. Therefore, when evaluating diabetic patients, its necessary not to overlook the findings suggestive of NDNP.

RESUMEN Antecedentes: Además de las nefropatías diabéticas (DNP), también se conoce la prevalencia frecuente de nefropatías no diabéticas (NDNP) en pacientes diagnosticados con Diabetes mellitus tipo 2 (DM). El diagnóstico precoz de estas condiciones es importante para el tratamiento y pronóstico de estos pacientes. Objetivo: Este estudio tuvo como objetivo investigar las relaciones entre los hallazgos clínicos y de laboratorio de las biopsias renales de pacientes diabéticos tipo 2. Material y Métodos: Revisamos retrospectivamente las historias clínicas de 140 pacientes que tenían diagnóstico de DM tipo 2, desde julio de 2020 hasta agosto de 2022, y se les realizó biopsia renal en las clínicas de nefrología del Hospital Umraniye. Se revisaron los resultados de biopsia renal, presencia de hipertensión arterial, retinopatía diabética, hematuria y proteinuria así como también la duración de la enfermedad, las indicaciones de la biopsia, la hemoglobina glucosilada (HbA1c), la creatinina sérica, el nitrógeno ureico en sangre, la albúmina y los niveles de proteinuria en orina de 24 h. El nivel de significación estadística se determinó como p<0,05. Resultados: se detectaron NDNP en el 43,7% de los pacientes. Entre estos, el diagnóstico más común fue la nefritis intersticial (20%). La indicación de biopsia más frecuente resultó ser la proteinuria en rango nefrótico (30,7%). La diferencia entre las indicaciones de biopsia renal de los pacientes DNP y NDNP fue estadísticamente significativa (p<0,001). Los pacientes con DNP tuvieron una mayor incidencia de retinopatía (60%, 11%, p<0,001). Se detectó una diferencia estadísticamente significativa entre la duración de la enfermedad de los grupos DNP y NDNP (11,23 +5,74 años, p:0,002). De acuerdo con el análisis de regresión multivariado, la presencia de DR y el valor de HbA1c en más del 7% tienen 4,482 y 4,591 veces mayor riesgo de incidencia de DNP (p = 0,021, p: 0,024). Conclusión: El diagnóstico precoz de DNP y NDNP de pacientes diabéticos mediante la realización de biopsias renales afecta el tratamiento y pronóstico de los pacientes. Por lo tanto, al evaluar pacientes diabéticos, es necesario no pasar por alto los hallazgos sugestivos de NDNP.

Crescentic IgA nephropathy following SARS-CoV-2 vaccination. Report of a case / Nefropatía por IgA extracapilar luego de la vacunación contra el SARS-CoV-2. Reporte de un caso

ABSTRACT Introduction: Studies have shown that the frequency of acute kidney injury (AKI) increases in patients with COVID-19. Acute tubular necrosis has been reported to be the most common damage in these patients, probably due to impaired renal perfusion. On the other hand, different complex pathophysiological processes may be involved due to viral infection's direct effects on the renin-angiotensin-aldosterone system, the activation of coagulopathy, the cytokine storm, and the activation of the immune system. Many glomerular diseases may be seen in these patients, like anca-associated vasculitis, membranous glomerulonephritis, and IgA nephropathy. Clinical case: We present a newly diagnosed crescentic IgA nephropathy (IgAN) case after a SARS-CoV-2 infection and vaccination. A 31-year-old man with no medical history presented with gross hematuria 24 hours after SARS-CoV-2 infection. Hematuria regressed spontaneously within three days. He was vaccinated with two doses of CoronaVac (Sinovac) three months after he had been infected by SARS-CoV-2. Then he was vaccinated with the Pfizer-BioNTech COVID-19 vaccine one month after the second dose of CoronaVac (Sinovac) vaccine. He presented with gross hematuria and subnephrotic proteinuria 24 hours after the first dose of the Pfizer-BioNTech COVID-19 vaccine. A kidney biopsy was performed and showed crescentic IgA nephropathy (IgAN). He was started on methylprednisolone and angiotensin receptor blocker. Patients who receive mRNA-based vaccines demonstrate robust antibody production against the receptor-binding domain (RBD) of the S1 protein. Similar to natural infection, due to the intense stimulation of immune response from mRNA-based vaccines compared to other vaccines, the patients may produce de novo antibodies, leading to IgA-containing immune-complex deposits. Conclusions: This case highlights the immunological effects of the novel mRNA-based SARS-CoV-2 vaccines. Nephrologists should be aware of new-onset hematuria or proteinuria after SARS-CoV-2 infection or mRNA-based SARS-CoV-2 vaccine.

RESUMEN Introducción: Los estudios han demostrado que la frecuencia de insuficiencia renal aguda (IRA) aumenta en pacientes con COVID-19. Se ha informado que la necrosis tubular aguda es el daño más común en estos pacientes, probablemente debido a la alteración de la perfusión renal. Por otro lado, pueden estar involucrados diferentes procesos fisiopatológicos complejos, debido a los efectos directos de la infección viral sobre el sistema renina-angiotensina-aldosterona, la activación de la coagulopatía, la tormenta de citoquinas y la activación del sistema inmunológico. En estos pacientes se pueden observar muchas enfermedades glomerulares, como vasculitis asociada a anca, glomerulonefritis membranosa y nefropatía por IgA. Caso clínico: Presentamos un caso de nefropatía IgA extracapilar (NIgA) de nuevo diagnóstico tras una infección por SARS-CoV-2 y vacunación. Un hombre de 31 años sin antecedentes médicos presentó hematuria macroscópica 24 horas después de la infección por SARS-CoV-2. La hematuria remitió espontáneamente en 3 días. Fue vacunado con dos dosis de CoronaVac (Sinovac) tres meses después de haber sido infectado por el SARS-CoV-2. Luego fue vacunado con la vacuna Pfizer-BioNTech COVID-19, un mes después de la segunda dosis de la vacuna CoronaVac (Sinovac). Presentó hematuria macroscópica y proteinuria no nefrótica 24 horas después de la primera dosis de la vacuna Pfizer-BioNTech COVID-19. Se realizó una biopsia renal que mostró NIgA extracapilar. Comenzó con metilprednisolona y bloqueador del receptor de angiotensina. Los pacientes que reciben vacunas basadas en ARNm demuestran anticuerpos contra el dominio de unión al receptor (RBD) de la proteína S1. De manera similar a la infección natural, debido a la fuerte estimulación de la respuesta inmunitaria de las vacunas basadas en ARNm en comparación con otras vacunas, los pacientes pueden producir anticuerpos de novo, lo que lleva a depósitos de complejos inmunitarios que contienen IgA. Conclusiones: Este caso destaca los efectos inmunológicos de las nuevas vacunas contra el SARS-CoV-2 basadas en ARNm. Los nefrólogos deben estar al tanto de la aparición de hematuria o proteinuria luego de la infección por SARS-CoV-2 o la vacuna contra el SARS CoV-2 basada en ARNm.

Relationships among oncostatin M, insulin resistance, and chronic inflammation: a pilot study

ABSTRACT Objective Activated macrophages (M1-type macrophages) in adipose tissue secrete many proinflammatory cytokines that induce insulin resistance (IR). Oncostatin M (OSM), a member of the interleukin-6 (IL-6) family of Gp130 cytokines, plays an important role in a variety of biological functions, including the regulation of inflammatory responses. Proinflammatory cytokines released in patients with IR trigger a chronic, low-grade inflammatory reaction in blood vessel walls. This inflammator response leads to endothelial damage, which is the main mechanism for atherosclerosis and many cardiovascular diseases. Animal studies have reported a relationship between OSM and IR. To the best of our knowledge, however, few clinical studies have examined this topic. Therefore, we studied the relationship between serum levels of OSM and IR. Subjects and methods This prospective cross-sectional case-control study enrolled 50 people with IR (according to the HOMA-IR and QUICKI indices) and 34 healthy controls. The fasting blood concentrations of insulin, glucose, blood urea nitrogen (BUN), creatinine, aspartate aminotransferase (AST), alanine aminotransferase (ALT), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride, total cholesterol, C-reactive protein (CRP), and OSM were determined. Results There were no significant differences between the two groups in age, sex, and HbA1c levels. Univariate analyses showed that waist circumference (WC) and levels of fasting glucose, insulin, CRP, HDL-C, OSM, HOMA-IR, and QUICKI differed between the two study groups. In multivariate analyses, both IR indices (QUICKI and HOMA) and OSM differed between the two groups. Conclusion OSM was correlated with the IR indices (QUICKI and HOMA). For simplicity, it might replace the other IR indices in the future. Further detailed studies are needed to confirm this.

Relationships among oncostatin M, insulin resistance, and chronic inflammation: a pilot study.

Objective Activated macrophages (M1-type macrophages) in adipose tissue secrete many proinflammatory cytokines that induce insulin resistance (IR). Oncostatin M (OSM), a member of the interleukin-6 (IL-6) family of Gp130 cytokines, plays an important role in a variety of biological functions, including the regulation of inflammatory responses. Proinflammatory cytokines released in patients with IR trigger a chronic, low-grade inflammatory reaction in blood vessel walls. This inflammator response leads to endothelial damage, which is the main mechanism for atherosclerosis and many cardiovascular diseases. Animal studies have reported a relationship between OSM and IR. To the best of our knowledge, however, few clinical studies have examined this topic. Therefore, we studied the relationship between serum levels of OSM and IR. Subjects and methods This prospective cross-sectional case-control study enrolled 50 people with IR (according to the HOMA-IR and QUICKI indices) and 34 healthy controls. The fasting blood concentrations of insulin, glucose, blood urea nitrogen (BUN), creatinine, aspartate aminotransferase (AST), alanine aminotransferase (ALT), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride, total cholesterol, C-reactive protein (CRP), and OSM were determined. Results There were no significant differences between the two groups in age, sex, and HbA1c levels. Univariate analyses showed that waist circumference (WC) and levels of fasting glucose, insulin, CRP, HDL-C, OSM, HOMA-IR, and QUICKI differed between the two study groups. In multivariate analyses, both IR indices (QUICKI and HOMA) and OSM differed between the two groups. Conclusion OSM was correlated with the IR indices (QUICKI and HOMA). For simplicity, it might replace the other IR indices in the future. Further detailed studies are needed to confirm this.

Serum Adropin Levels Are Reduced in Adult Patients with Nonalcoholic Fatty Liver Disease.

OBJECTIVES: Adropin is a novel marker of metabolic syndrome and insulin resistance. The aim of this study was to explore the association of serum adropin levels with hepatosteatosis among adult patients. MATERIALS AND METHODS: Serum biochemical parameters including liver and renal function tests, insulin levels, and serum adropin levels were compared between adult patients with nonalcoholic fatty liver disease (NAFLD) and healthy control cases. RESULTS: A total of 51 patients with a mean age of 37.9 ± 9.96 years diagnosed with grade 2-3 hepatosteatosis and 30 healthy control cases with a mean age of 34.8 ± 9.5 years were included in the study. Serum adropin levels in the NAFLD group were statistically significantly lower than in the control cases (588.4 ± 261.0 vs. 894.2 ± 301.2, respectively; p < 0.001). The study participants were further subdivided into 2 groups as patients with (n = 35) or without (n = 46) insulin resistance using the serum homeostatic model of assessment-insulin resistance (HOMA-IR). Serum adropin levels were statistically significantly lower in patients with insulin resistance (p < 0.01). There was a negative correlation between adropin levels and serum insulin, HOMA-IR, urea, gamma-glutamyl transferase, total cholesterol, and triglyceride levels. CONCLUSION: We observed a decrease in serum adropin levels among adult patients with NAFLD. We also found lower levels of serum adropin in patients with insulin resistance, supporting previous data in the literature. Studies investigating the association of adropin levels with other inflammatory parameters are warranted to define its exact role in the pathogenesis of hepatosteatosis.

Choice of treatment based on Turkish hypertension consensus report: Do we follow the recommendations?

OBJECTIVE: The aim of this study was to determine how often the recommendations of the Turkish Hypertension Consensus Report are followed, and to draw attention to the report. METHODS: The demographic information of 1000 patients diagnosed with hypertension and the details of the antihypertensive medications prescribed at the outpatient service of a tertiary care hospital were recorded, and the data were compared with the recommendations of the report. RESULTS: The mean age of the patients was 62±11 years. In all, 623 (62.3%) of the 1000 patients were women, and 377 (37.7%) were men. A combination of an angiotensin II receptor blocker (ARB) and a diuretic was the most frequently observed prescription. A diuretic was the most used antihypertensive drug (58.7%), followed by an ARB (48.8%). However, as a monotherapy, a calcium channel blocker (CCB) was the most commonly used antihypertensive drug (19.2%). The most frequently used antihypertensive drug group in older patients was diuretics (63.6%), as proposed in the report. Beta blockers (49.1%) were used more often than expected. For the diabetic group also, a diuretic (60.7%) was the most frequently used antihypertensive drug, followed by an ARB (51.1%) and a CCB (45.2%). Angiotensin-converting enzyme (ACE) inhibitors (34.6%) were the fifth most preferred antihypertensive drug class. However, when ACE inhibitors and ARBs were considered as a single group, known as renin-angiotensin system (RAS) blockers, these RAS blockers were the most prescribed antihypertensive drug class, followed by diuretics. In the group of patients with coronary artery disease, treatment was found to be generally consistent with the report, but the use of diuretics was greater than expected. Lastly, 124 of 160 patients who had chronic kidney disease were given RAS blocker therapy, which was in line with the consensus report recommendations. CONCLUSION: Antihypertensive therapies were individualized, as suggested by the consensus report. However, there are proposals still to be considered in special patient groups.

Cisplatin nephrotoxicity is not detected by urinary cell-cycle arrest biomarkers in lung cancer patients.

PURPOSE: Cisplatin is a chemotherapeutic agent with potential nephrotoxicity. Delayed increase in serum creatinine after cisplatin administration shows that serum creatinine may not be a sufficient marker for early detection of nephrotoxicity. Urinary insulin-like growth factor binding protein-7 (IGFBP7) and tissue inhibitor of metalloproteinases-2 (TIMP-2) which are cell-cycle arrest biomarkers have been proposed recently for early detection of acute kidney injury (AKI). Herein, we evaluated urinary TIMP-2/IGFBP7 levels before and after cisplatin administration to patients with lung cancer and their role was examined in the early diagnosis of AKI. METHODS: Patients with glomerular filtration rate above 60 mL/min who had cisplatin treatment were enrolled. Urinary TIMP-2/IGFBP7 and serum creatinine levels were measured before and at 24th hour after cisplatin administration. Serum creatinine level was also measured at 48th hour after treatment. RESULTS: Cisplatin-associated AKI was detected in 13 patients (28%) among the 45 patients enrolled. There was no difference between creatinine, IGFBP7 and (IGFBP7 × TIMP-2)/1000 levels before and after treatment; urinary TIMP-2 level at 24th hour was significantly higher than the level before the treatment (p = 0.02). (IGFBP7 × TIMP-2)/1000 values were not different between patients with or without AKI. The area under the curve of (IGFBP7 × TIMP-2)/1000 at 24th hour of the treatment was 0.46 (CI 0.26-0.67). CONCLUSION: Although urinary IGFBP7 and TIMP-2 levels are used as biomarkers for early detection of AKI for patients in intensive care units and after surgery, they seem not to be useful for early detection of AKI due to cisplatin.