Transient Proteinuria Research Articles

Transient albuminuria in the setting of short-term severe hyperglycemia in type 1 diabetes

In a cohort of 1817 children with type 1 diabetes (T1D), short-term hyperglycemia was associated with transient albuminuria (11 % during new-onset T1D without diabetic ketoacidosis (DKA), 12 % during/after DKA, 6 % during routine screening). Our findings have implications regarding future risk of diabetic kidney disease and further investigation is needed.

ALBUMINURIA IS ASSOCIATED WITH LESS EFFORT TOLERANCE IN HYPERTENSION AND DIABETES

Introduction: The presence of albuminuria is an adverse marker of renal dysfunction progression. Hypertension and diabetes mellitus predispose to albuminuria. However, not all hypertensive and diabetic patients have albuminuria, so it is relevant to identify risk factors associated to this abnormality. The acute effect of intense physical activity may lead to transient albuminuria. On the other hand, physical inactivity is associated with risk factors for albuminuria Objective: To analyze the association between activity levels or physical performance and albuminuria in hypertensive and/or diabetic patients treated at basic health services. Methodology: A prospective cross-sectional study with hypertensives and/or diabetics subjects. The patients were evaluated in regard of albuminuria, clinical, laboratory and physical test performance variables. Results: There was no association between the degree of albuminuria and demographic, anthropometric, laboratory variables, functional capacity and level of physical activity. The degree of albuminuria was associated with systolic blood pressure, as well as the perception of effort, obtained by Borg Scale during the test in univariate analysis (odds ratio 4.11 with 95% confidence interval from 1.18 to 14.37, p = 0.027) and adjusted for systolic blood pressure and diabetes (odds ratio 3.02 with 95% confidence interval from 1.35 to 6.75; p = 0.007). Conclusion: there was association between albuminuria and perceived effort, as well with systolic blood pressure. There was not with association physical performance or level of activity. Further studies are needed to elucidate the association of albuminuria with Borg Scale.

Albuminuria Is Affected by Urinary Tract Infection: A Comparison between Biochemical Quantitative Method and Automatic Urine Chemistry Analyzer UC-3500.

The automated urine reagent strip test is a cost-effective tool for detecting albuminuria in patients. However, prior research has not investigated how urinary tract infections (UTIs) affect the test's accuracy. Therefore, this study aims to assess the impact of UTIs on albuminuria diagnosis using both the biochemical quantitative method and the test strip method of the Fully Automatic Urine Chemistry Analyzer, UC-3500 (Sysmex, Kobe, Japan). From March to December 2019, we prospectively collected midstream urine from adult female UTI patients before and after one week of cephalexin treatment. The urine samples were subjected to culture, routine urinalysis, and albuminuria diagnosis using the biochemical quantitative method and UC-3500. Albuminuria was defined as a urine albumin to creatinine ratio (UACR) ≥ 30 mg/g in the biochemical quantitative method. The results were compared between the two methods. Among fifty-four female patients (average age: 50.5 ± 4.4 years) with UTIs, 24 (44.44%) had transient albuminuria. The quantitative UACR significantly decreased after one week of antibiotic treatment (median: 53 mg/g to 9 mg/g; median difference: -0.54, p < 0.0001). UC-3500 exhibited a higher false positive rate for diagnosing albuminuria during UTIs (42%) compared to after treatment (19%). Its agreement with the biochemical quantitative method was moderate during UTI (κ = 0.49, 95% confidence interval [CI]: 0.24-0.73) and good after treatment (κ = 0.65, 95% CI: 0.45-0.86). UC-3500's accuracy in diagnosing albuminuria is influenced by UTIs, leading to either transient albuminuria or a false positive reaction of the test strip. UTI should be excluded or treated before its application in albuminuria screening.

#4875 MANAGEMENT OF TUBULOINTERSTITIAL DISEASE IN PREGNANCY: TEN-YEARS EXPERIENCE OF A NEPHRO-OBSTETRIC CLINIC

Abstract Background and Aims Tubular renal acidosis and salt losing nephropathies are rare conditions but their management during pregnancy that can be challenging due to the physiological adaptation of kidney function. Herein, the authors report the management and outcomes of 7 gestations in patients with Gitelman disease (GS) and renal tubular acidosis (RTA). Method Retrospective analysis of maternal, obstetric and perinatal outcomes of pregnant women with tubulointerstitial diseases surveilled at our Nephro-Obstetric clinic from 2011 to 2021. Results We evaluated 7 pregnancies in 5 women. Mean age was 29 years [21-36]. They were all caucasian. Genetic diagnosis was performed during pregnancy in only one patient. Tubular disorder was caused by Gitelman disease in 3 patients and by renal tubular acidosis in 2 patients (ATP6VA4 and REN genes mutations). There were 4/1 patients in CKD G1/G3a, respectively, and none developed renal function deterioration. Only one patient developed transient proteinuria during both gestations and all patients had a low blood pressure profile. Management during the first trimester was especially challenging in GS patients, due to nausea, vomiting and hyperemesis gravidarum, which required hospital admission for intravenous potassium chloride therapy in all GS patients during the first trimester. Potassium levels in GS patients were generally below normal levels throughout pregnancy (mean 3 meq/L; 2,2-3,4 meq/L), even with progressive increase in therapy. Pre-pregnancy potassium chloride replacement increased from 4–10 tablets of 600 mg/day to a maximum of 9–21 tablets/day. One patient was also treated with spironolactone. The need for oral magnesium slightly increased from 2–3 ampoules of 1500mg/day to 2–4 ampoules/day. GS patients frequently complained of astenia and cramps. Regarding RTA patients, there was also a need to increase sodium bicarbonate dosage from 3–4.5g/day to a maximum of 2–8g /day. Regarding obstetric and perinatal outcomes, none of the patients developed preclampsia, mean gestational age at delivery was 40 weeks (38-41), mean birth weight was 3233g (2775-3825) and mean Apgar score was 10/10/10 at 1st, 5th and 10th minutes respectively. Conclusion In GS patients, management in the first trimester of pregnancy can be challenging due to nausea and vomiting, generally requiring admission for therapy with iv potassium. In spite of increasing doses in oral supplementation, ionic and acid base homeostasis during pregnancy is difficult to achieve. In our small series, maternal, obstetric and perinatal outcomes do not seem to be affected by this unbalance.

The dynamics of hypertension and renal function in CKD and non-CKD patients affected with COVID-19 – final results of BIRCOV trial

Introduction and aim. There is evidence in the literature about a change in the effectiveness of inhibitors of the renin-angiotensin system (iRAS) in people with COVID-19. Considering different mechanisms of pressure reduction by different iRAS groups, one can expect differences in people with COVID-19 receiving these drugs. The aim of angiotensin-converting enzyme inhibitors (ACEi), angiotensin II receptor blockers (ARB) and direct renin inhibitors (DRi) usage in COVID-19 (BIRCOV study) was to pinpoint clinical and laboratory differences in people with hypertension who received iRAS and suffered coronavirus infection. Material and methods. An open prospective trial of 108 patients was performed in subjects suffering from COVID-19 who have been receiving iRAS: ACEi, ARB or DRi as basic antihypertensive therapy. The disease follow-up was 12 and 24 weeks. A blood pressure (BP) measurement was performed the week before COVID-19 and up to 24 weeks from the disease onset. Subanalysis in patients with chronic kidney disease (CKD) was performed. Results. In patients with COVID-19, a change in the effectiveness of antihypertensive therapy depending on the type of drug in the iRAS group has been documented in the first 4 weeks from the onset of the disease. The use of ACEi had significantly increased the risk of severe hypotension, unlike ARBs that do not cause hypotension. The synchronous decline of estimated glomerular filtration rate (eGFR) and systolic BP was more pronounced in CKD patients followed by albuminuria incidence. The greatest decrease in eGFR was in people taking ACEi. Conclusion. People with grade 1-2 hypertension who are constantly receiving RAS inhibitors suffering from COVID-19 may develop hypotension with ACEi. COVID-19 leads to transient albuminuria and decreased glomerular filtration rate, which is especially dangerous for people with CKD 4-5.

Measurement of urinary protein in children

Proteinuria is an early hallmark of kidney disease and a major risk factor for systemic cardiovascular diseases. There are several methods to measure proteinuria, such as the urine dipstick test, 24-hour urinary protein excretion method, and spot urine for the protein-to-creatinine ratio. The urine dipstick test is simple but inaccurate. The 24-hour urinary protein excretion method is the gold standard; however, it is cumbersome, especially in children. Spot urine for the protein-to-creatinine ratio is simple and accurate, but has limitations. Specific urinary protein such as albumin can be measured instead of the total protein content. Tests should be avoided in situations that cause transient proteinuria or false-positive results. It should be performed correctly, and its limitations should be recognized and interpreted accurately.

Treatment of flurbiprofen overdose with therapeutic plasma exchange in a dog

AbstractA 2‐year‐old, spayed, female boxer was referred after ingestion of 30 mg/kg flurbiprofen. Treatment included therapeutic plasma exchange in addition to conventional medical management. Therapeutic plasma exchange was efficient in removing flurbiprofen from the dog's plasma, with one complication being a transient face swelling. Despite three‐times lethal dose (LD50) intoxication, the patient fully recovered after transient azotaemia and proteinuria. This case presentation confirms that extracorporeal blood purification may be effective in treating a lethal consumption of flurbiprofen and may provide important resources for human and veterinary patient intoxication care, as flurbiprofen is widely used.

Comparison of renal histopathology in three patients with gross hematuria after SARS-CoV-2 vaccination.

We present three cases of IgA nephropathy with gross hematuria following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) messenger RNA (mRNA) vaccination. Case 1 was a 60-year-old woman who has previously experienced transient proteinuria. Case 2 was a 22-year-old woman with no history of urinary abnormality. Finally, case 3 was a 66-year-old woman who has had microscopic hematuria since she was in her 50s. They were all diagnosed as IgA nephropathy with little histological active lesion. Their renal function and proteinuria improved without the use of corticosteroids. There were differences in the findings of vascular endothelial damage based on the time between the appearance of gross hematuria and renal biopsy. Glomerular endocapillary damage could be a part of the mechanism triggered by mRNA vaccination. When a patient presents with gross hematuria following vaccination, a comprehensive approach including renal biopsy should be considered.

Epidemiology, severity, and risk of SARS-CoV-2-related relapse in children and young adults affected by idiopathic nephrotic syndrome: a retrospective observational cohort study.

BackgroundChildren with underlying kidney diseases display a mild course of SARS-CoV-2 infection, but they only accounted for a minority of cases until the spread of the Omicron variant. Nonetheless, idiopathic nephrotic syndrome (INS) has been advocated as a predictor of worse outcome.MethodsWe investigated the spread, severity, and risk of relapse related to SARS-CoV-2 infection among children with INS. The incidence and characteristics of SARS-CoV-2 infections, immunosuppression, and vaccination status were retrospectively collected from the beginning of the pandemic to May 31, 2022.ResultsWe enrolled 176 patients (73 females, median age 10.22 years); 28 had a steroid-resistant disease, and 108 (61.4%) were on immunosuppressive therapy. Sixty-one (34.7%) patients reported a SARS-CoV-2 infection, with incidence peaking between December 2021 and January 2022. No hospitalization or deaths were reported, and symptoms were absent or mild. The rate of SARS-CoV-2 infection was similar in children with and without immunosuppression (33.8% vs 35.2%; p = 0.85). None of the 38 immunosuppressed patients discontinued the therapy, but they had a longer time to negativization (13.31 vs. 10.04 days; p = 0.03). Proteinuria was detected in 7 patients, but only one had a relapse requiring steroid therapy, with prompt remission and a mild course.ConclusionsAfter the spread of the Omicron variant, the rate of SARS-CoV-2 infection in children with INS was much higher than previously reported. In this large cohort, symptoms were mild, even in immunosuppressed patients and those with proteinuria. During the infection, transient proteinuria was common with a low rate of relapses.Graphical abstract A higher resolution version of the Graphical abstract is available as Supplementary informationSupplementary InformationThe online version contains supplementary material available at 10.1007/s00467-022-05736-6.

Transiently Observed Trace Albuminuria on Urine Dipstick Test Is Associated With All-Cause Death, Cardiovascular Death, and Incident Chronic Kidney Disease: A National Health Insurance Service-National Sample Cohort in Korea.

IntroductionAlbuminuria is a well-known risk factor for end-stage kidney disease, all-cause mortality, and cardiovascular mortality, even when the albumin-to-creatinine ratio is <30 mg/g. However, the association between transiently observed trace albuminuria and these major adverse outcomes has not yet been reported. This study aimed to examine the effect of transient albuminuria on these major adverse outcomes using the National Health Insurance Service data in Korea.Methods and ResultsThe National Health Insurance Service-National Sample Cohort from Korea, followed from 2002 to 2015, consisted of 1,025,340 individuals, accounting for 2.2% of the total Korean population. We analyzed the effect of transient albuminuria on all-cause death, cardiovascular death, and incident chronic kidney disease (CKD) and compared it with the group without albuminuria. Among 1,025,340 individuals, 121,876 and 2,815 had transient albuminuria and no albuminuria, respectively. Adjusted hazard ratios of the transient albuminuria group for cardiovascular death and incident CKD were 1.76 (1.01–3.08) and 1.28 (1.15–1.43), respectively. There were significant differences in all-cause death, cardiovascular death, and incident CKD between the two groups after propensity score matching (p = 0.0037, p = 0.015, and p < 0.0001, respectively). Propensity score matching with bootstrapping showed that the hazard ratios of the transient albuminuria group for all-cause death and cardiovascular death were 1.39 (1.01–1.92) and 2.18 (1.08–5.98), respectively.ConclusionsIn this nationwide, large-scale, retrospective cohort study, transient albuminuria was associated with all-cause death, cardiovascular death, and incident CKD, suggesting that transient albuminuria could be a risk marker for adverse outcomes in the future, and that its own subclinical phenotype could play an important role during the course of CKD.

Renal outcomes of transient proteinuria in patients with systemic lupus erythematosus treated with corticosteroid therapy alone

To examine the long-term renal outcomes of systemic lupus erythematosus (SLE) patients with transient proteinuria. The medical records of SLE patients who showed improvement in proteinuria (urine protein/creatinine ratio < 500mg/g) after receiving corticosteroid therapy without immunosuppressants were reviewed. A total of 38 patients (mean creatinine: 0.74 ± 0.33mg/dl) showed an improvement of proteinuria (1361 ± 1053mg/g to 289 ± 125mg/g) after receiving corticosteroid therapy alone for a median of 25days (IQR, 10-55). After follow-up (median, 23months [IQR, 15-121]), 25 (65%) patients maintained the resolution of proteinuria without renal dysfunction. The remaining 13 (34%) patients experienced a relapse of proteinuria during a median follow-up of 13.9months from baseline (IQR, 1.6-25). There was no significant difference in the baseline laboratory data according to the occurrence of proteinuria relapse, but longer SLE disease duration at baseline was associated with the risk of proteinuria relapse (HR, 1.007; p = 0.033). Of the patients who underwent renal biopsy with proteinuria relapse, class II (53%) lupus nephritis was the most common pathology. None progressed to end-stage renal disease during an additional long-term further follow-up of median 33 months (IQR, 22-49) after proteinuria relapse. Two-thirds of SLE patients who showed improvement in proteinuria after corticosteroid alone maintained the non-proteinuric state without renal dysfunction. Thus, performing a kidney biopsy at the first onset of proteinuria could be delayed in patients who show an improvement in proteinuria after treatment with corticosteroids.

Increased Heparanase Levels in Urine during Acute Puumala Orthohantavirus Infection Are Associated with Disease Severity.

Old–world orthohantaviruses cause hemorrhagic fever with renal syndrome (HFRS), characterized by acute kidney injury (AKI) with transient proteinuria. It seems plausible that proteinuria during acute HFRS is mediated by the disruption of the glomerular filtration barrier (GFB) due to vascular leakage, a hallmark of orthohantavirus–caused diseases. However, direct infection of endothelial cells by orthohantaviruses does not result in increased endothelial permeability, and alternative explanations for vascular leakage and diminished GFB function are necessary. Vascular integrity is partly dependent on an intact endothelial glycocalyx, which is susceptible to cleavage by heparanase (HPSE). To understand the role of glycocalyx degradation in HFRS–associated proteinuria, we investigated the levels of HPSE in urine and plasma during acute, convalescent and recovery stages of HFRS caused by Puumala orthohantavirus. HPSE levels in urine during acute HFRS were significantly increased and strongly associated with the severity of AKI and other markers of disease severity. Furthermore, increased expression of HPSE was detected in vitro in orthohantavirus–infected podocytes, which line the outer surfaces of glomerular capillaries. Taken together, these findings suggest the local activation of HPSE in the kidneys of orthohantavirus–infected patients with the potential to disrupt the endothelial glycocalyx, leading to increased protein leakage through the GFB, resulting in high amounts of proteinuria.

Body Mass Index and the Risk of Persistent Proteinuria in Middle-Aged Men: The Kansai Healthcare Study

Introduction: Proteinuria is a risk factor for end-stage renal failure. However, it is not known whether body mass index (BMI) is prospectively associated with the risk of future developing proteinuria, taking into account transient proteinuria. Methods: We enrolled 9,320 nondiabetic Japanese middle-aged men who had no proteinuria, an estimated glomerular filtration rate ≥60 mL/min/1.73 m², no history of cancer, and no use of antihypertensive medications at baseline. “Any proteinuria” was defined as proteinuria detected for the first time during the follow-up period regardless of its frequency. “Persistent proteinuria” was defined as proteinuria that was detected at least twice consecutively at annual examinations and did not return to negative until the end of the follow-up. Results: During the 11-year follow-up period, 1,972 cases of any proteinuria and 151 cases of persistent proteinuria were confirmed. Both lower and higher BMI were associated with the risk of any proteinuria. As for persistent proteinuria, in those with a BMI ≥20 kg/m², higher BMI was associated with a higher risk of future persistent proteinuria. The association between BMI and the risk of persistent proteinuria was stronger than that between BMI and any proteinuria. In multiple-adjusted model, hazard ratios of persistent proteinuria for BMI <18.0, 18.0–19.9, 20.0–21.9, 22.0–23.9, 24.0–25.9, 26.0–27.9, and ≥28.0 kg/m² were 1.52 (95% confidence interval 0.51–4.49), 1.07 (0.49–2.29), 1.00 (reference), 1.14 (0.64–2.01), 1.89 (1.09–3.27), 2.12 (1.15–3.93), and 3.85 (2.03–7.30), respectively. Discussion/Conclusion: In those with a BMI ≥20 kg/m², higher BMI was associated with a higher risk of future persistent proteinuria and any proteinuria. This relationship was stronger for persistent proteinuria than for any proteinuria.

Final results of BIRCOV trial (ARB, ACEI, DRi in COVID-19)

Background. The question of the possible effect of the inhibitors of the renin-angiotensin system (iRAS) on hypertensive subjects who fell ill with COVID-19 has been discussed in the literature. SARS-CoV-2 is well-known to use an angiotensin-converting enzyme 2 receptors facilitating virus entry into host cells. There are three possible mechanisms of angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB) effect in COVID-19 in clinical practice: with worsening, neutral, or helpful function. Considering the different mechanisms of blood pressure reduction by iRAS, one can expect differences in people with COVID-19 receiving these drugs. The purpose of the BIRCOV study is to pinpoint possible clinical and laboratory differences in hypertensive people who received iRAS and suffered from coronavirus infection. Materials and methods. Patient-Oriented Evidence that Matters (POEM) intervention was designed as an open prospective randomized two medical centers trial in subjects suffering from COVID-19 who have been receiving iRAS, either ACEi, ARB, or direct renin inhibitor (DRi) as basic antihypertensive therapy. One hundred and twenty people with stage 1–2 hypertension have been screened, 108 subjects were enrolled in the BIRCOV study. COVID-19 was confirmed by a PCR test; the disease follow-up was divided into 2 periods: up to 12 weeks and up to 24 weeks. The primary outcome measure was as follows: blood pressure (BP) was known one week before COVID-19 onset and was measured during the disease on weeks 2, 4, 12, 24. The secondary outcome measures were clinical features. Subanalysis in patients with chronic kidney disease (CKD) was performed. Results. All patients were randomized into 3 groups who received: ACEi — 42 (39%), ARB — 35 (32%), or DRi — 31 (29%). The BIRCOV trial documented the trend of BP lowering in the first two weeks of the COVID-19 disease with its gradual return to baseline values up to the 12th week. Twenty-three (21%) patients have withdrawn medicine for up to 2 weeks due to severe hypotension. However, the BP values after COVID-19 in most subjects remained lower than the baseline ones for 4 weeks. The use of ACE inhibitors significantly increased the risk of withdrawal compared to DRi (RR 1.648; 95% CI 0.772–3.519; NNT 7.0) and ARB (RR 13.023; 95% CI 1.815–93.426; NNT 2.9) due to COVID-19. The synchronous decline of estimated glomerular filtration rate (eGFR) and systolic BP was more pronounced in CKD patients. The greatest decrease in eGFR was noted in people who have been taking ACEi. The drop in eGFR ranged from 23% in CKD stage 1 to 45% in CKD stage 4. Two people required short-term dialysis. The analysis of secondary outcome points demonstrated that in 23% of people without preceding albuminuria it developed in the A2 range. During 12 weeks of observation, 81% of patients had spontaneous albuminuria reduction. Post-COVID-19 (above 12 weeks) albuminuria remained in 19% of patients, 90% of them had a history of CKD. Patients with preceding CKD had an increase in albuminuria in 78% of cases, and its return to the baseline was observed only in 24% of patients by the 12th week and in 49% of individuals in 24 weeks. Conclusions. People with stage 1–2 hypertension who are receiving chronic iRAS and suffer from COVID-19 may develop hypotension with ACE inhibitors. COVID-19 leads to transient albuminuria and decreased glomerular filtration rate, which is especially dangerous for people with CKD.

Does intravenous contrast medium administration result in altered renal biomarkers? A study in clinically stable cats with and without azotemia.

The aim of this study was to determine the prevalence of post-contrast acute kidney injury or comparable side effects on kidney function in cats receiving the non-ionic, iodinated agent ioversol and/or paramagnetic agent gadoteric acid. Fifty-two animals were divided into four groups on the basis of contrast medium administration for imaging: ioversol (n = 27), gadoteric acid (n = 12), dual contrast media (n = 4) or control, which received an infusion of isotone intravenous fluids only during anaesthesia (n = 9). Blood and urine samples were obtained three times after contrast administration and compared with values obtained prior to administration of the contrast medium. Creatinine (<1.60 mg/dl), symmetric dimethylarginine (SDMA; ⩽14 μg/dl), urine protein:creatinine ratio (UPC; <0.2) and critical differences for creatinine (<0.3 mg/dl) and SDMA (<5.98 μg/dl) were measured. No significant short-term effects on mean creatinine, SDMA and UPC measurements were seen. Borderline proteinuria (UPC, 0.2-0.4) was detected in 11.4% of cases after contrast media administration. A UPC of more than 0.2 in five cases indicated that contrast media may affect kidney function, leading to (transient) proteinuria. This study found no side effect on renal function following the administration of ioversol or gadoteric acid, provided patients were adequately hydrated. However, the clinical relevance of proteinuria in some cats needs to be evaluated in future studies.

Laboratory monitoring of nusinersen safety.

This retrospective study reports our tertiary care center's experience with intrathecal nusinersen administration in children and adults with spinal muscular atrophy (SMA). We reviewed safety monitoring laboratory results and need for procedural sedation and fluoroscopy-guidance in all SMA patients receiving nusinersen between February 2017 and March 2020. Fifty-eight patients ages 1 mo- 56 y received 494 nusinersen doses. There were 166 laboratory abnormalities in 45 patients. Most were either mild (145 [87.3%]) or were transient proteinuria (18 [10.8%]). None altered nusinersen treatment. Twenty-eight patients required either general anesthesia (75 doses) or anxiolysis with oral midazolam (133 doses, including 6 patients [23 doses] with SMA type I). Eight patients with complicated spines (45 doses) required fluoroscopic guidance. One treatment-related serious adverse event (emesis leading to intubation) occurred during general anesthesia. Two children had asymptomatic increased intracranial pressure. No patients discontinued treatment due to adverse events. Intrathecal nusinersen is generally safe and well-tolerated, including in patients requiring oral anxiolysis, general sedation, and fluoroscopic guidance. Frequent serial laboratory monitoring did not identify any persistent significantly abnormal findings or alter treatment.

Proteinuria

Key Points Proteinuria on routine screening of children without symptoms most often is either orthostatic or transient, not pathological. Orthostatic (postural) proteinuria is most common. Transient proteinuria can result from stressors such as fever or vigorous exercise. Persistent (fixed) proteinuria can be asymptomatic, signaling underlying glomerular or tubular renal disease.

Clinical characteristics of hospitalized patients with 2019 novel coronavirus disease indicate potential proximal tubular dysfunction.

Clinical characteristics of hospitalized patients with 2019 novel coronavirus disease indicate potential proximal tubular dysfunction.

37-Year-Old Woman With Bilateral Lower Extremity Edema, Proteinuria, and Microscopic Hematuria

37-Year-Old Woman With Bilateral Lower Extremity Edema, Proteinuria, and Microscopic Hematuria

Flash-Like Albuminuria in Acute Kidney Injury Caused by Puumala Hantavirus Infection.

Transient proteinuria and acute kidney injury (AKI) are characteristics of Puumala virus (PUUV) infection. Albuminuria peaks around the fifth day and associates with AKI severity. To evaluate albuminuria disappearance rate, we quantified albumin excretion at different time points after the fever onset. The study included 141 consecutive patients hospitalized due to acute PUUV infection in Tampere University Hospital, Finland. Timed overnight albumin excretion (cU-Alb) was measured during the acute phase in 133 patients, once or twice during the convalescent phase within three months in 94 patients, and at six months in 36 patients. During hospitalization, 30% of the patients had moderately increased albuminuria (cU-Alb 20–200 μg/min), while 57% presented with severely increased albuminuria (cU-Alb >200 μg/min). Median cU-Alb was 311 μg/min (range 2.2–6460) ≤7 days after fever onset, 235 μg/min (range 6.8–5479) at 8–13 days and 2.8 μg/min (range 0.5–18.2) at 14–20 days. After that, only one of the measurements showed albuminuria (35.4 μg/min at day 44). At six months, the median cU-Alb was 2.0 μg/min (range 0.6–14.5). Albuminuria makes a flash-like appearance in PUUV infection and returns rapidly to normal levels within 2–3 weeks after fever onset. In the case of AKI, this is a unique phenomenon.