Adult ; Aged ; Aged, 80 and over ; Betacoronavirus ; Coronavirus Infections ; complications ; Female ; Glomerular Filtration Rate ; Glycosuria ; epidemiology ; Hospitalization ; Humans ; Hyponatremia ; epidemiology ; Kidney Tubules, Proximal ; physiopathology ; Male ; Middle Aged ; Pandemics ; Pneumonia, Viral ; complications ; Retrospective Studies

We aimed to identify the clinical variables associated with a better glucose-lowering response to the sodium glucose cotransporter 2 inhibitor ipragliflozin in people with type 2 diabetes mellitus (T2DM). We especially focused on urinary glucose excretion (UGE). This was a single-arm multicenter prospective study. A total of 92 people with T2DM aged 20 to 70 years with glycosylated hemoglobin (HbA1c) levels ≥7.0% and ≤9.5% were enrolled. Ipragliflozin (50 mg) was added to the background therapy for these people for 12 weeks. After 3 months treatment with ipragliflozin, the mean HbA1c levels were decreased from 7.6% to 6.9% and 62.0% of the people reached the HbA1c target of less than 7.0% (P<0.001). In addition, body weight, blood pressure, and lipid parameters were improved after ipragliflozin treatment (all P<0.001). The baseline HbA1c (r=0.66, P<0.001) and morning spot urine glucose to creatinine ratio (r=−0.30, P=0.001) were independently associated with the HbA1c reduction. Ipragliflozin treatment for 12 weeks improves glycemic control and other metabolic parameters. A higher HbA1c and lower UGE at baseline predicts a better glucose-lowering efficacy of ipragliflozin.
Blood Pressure ; Body Weight ; Creatinine ; Diabetes Mellitus, Type 2 ; Glucose ; Glycosuria ; Hemoglobin A, Glycosylated ; Prospective Studies ; Sodium ; Sodium-Glucose Transporter 2

BACKGROUND: Yersinia pseudotuberculosis is known to cause fever, gastroenteritis, or acute kidney injury (AKI). There have been several Y. pseudotuberculosis infection outbreaks to date associated with ingestion of contaminated food or unsterile water. While this disease was considered to have practically been eradicated with the improvement in public health, we encountered several cases of AKI associated with Yersinia infection. METHODS: We retrospectively collected data from medical records of patients with suspected Y. pseudotuberculosis infection who visited Seoul National University Children’s Hospital in 2017. RESULTS: There were nine suspected cases of Yersinia infection (six males and three females; age range 2.99–12.18 years). Among them, five cases occurred in May, and seven patients were residing in the metropolitan Seoul area. Three patients had history of drinking mountain water. Every patient first presented with fever for a median of 13 days, followed by gastrointestinal symptoms and oliguria. Imaging studies revealed mesenteric lymphadenitis, terminal ileum wall thickening, and increased renal parenchymal echogenicity. Creatinine levels increased to 5.72 ± 2.18 mg/dL. Urinalysis revealed sterile pyuria, proteinuria, and glycosuria. Oliguria continued for 4 to 17 days, and two patients required dialysis; however, all of them recovered from AKI. Mucocutaneous manifestations developed later. In the diagnostic work-up, Yersinia was isolated from the stool culture in one patient. Anti-Yersinia immunoglobulin (Ig) A and IgG were positive in 6 patients. CONCLUSION: Y. pseudotuberculosis infection is an infrequent cause of interstitial nephritis presenting with AKI. When a patient presents with fever, gastroenteritis, and AKI not resolving despite hydration, the clinician should suspect Y. pseudotuberculosis infection.
Acute Kidney Injury ; Creatinine ; Dialysis ; Disease Outbreaks ; Drinking ; Eating ; Female ; Fever ; Gastroenteritis ; Glycosuria ; Humans ; Ileum ; Immunoglobulin G ; Immunoglobulins ; Male ; Medical Records ; Mesenteric Lymphadenitis ; Nephritis, Interstitial ; Oliguria ; Proteinuria ; Public Health ; Pyuria ; Retrospective Studies ; Seoul ; Urinalysis ; Water ; Yersinia Infections ; Yersinia pseudotuberculosis ; Yersinia

BACKGROUND/AIMS: This study was designed to investigate the roles of aristolochic acid I (AA-I) and hypokalemia in acute aristolochic acid nephropathy (AAN). METHODS: After an adaptation period (1 week), a total of 40 C57BL/6 mice (male, 8 weeks old) were divided into four groups: I (control group), II (low potassium [K] diet), III (normal K diet with administration of AA-I [10 mg/kg weight]), and IV (low K diet with AA-I). After collecting 24 hours of urine at 2 weeks, the mice were sacrificed, and their blood and kidneys were obtained to perform immunochemical staining and/or Western blot analysis. RESULTS: Proteinuria, glycosuria, and increased fractional excretion of sodium and K were prominent in groups III and IV (p < 0.05). Diffuse swelling and poor staining of collecting duct epithelial cells were evident in the medullas of group II. Typical lesions of toxic acute tubular injury were prominent in the cortices of groups III and IV. Α-Smooth muscle actin (α-SMA) was higher in the cortices of the mice in groups III and IV versus group II (p < 0.05), and higher in the medullas of group IV than groups I and III (p < 0.05). E-cadherin was higher in the cortices of groups III and IV compared to group I (p < 0.05). The F4/80 value was higher in the cortices and medullas of groups II, III, and IV compared to group I (p < 0.05), particularly in the case of group II. CONCLUSIONS: AA-I can induce acquired Fanconi syndrome in the acute stage of AAN. Macrophages appear to play a key role in the pathogenesis of AAN and hypokalemic nephropathy. It remains uncertain whether hypokalemia plays any role in AAN and hypokalemia.
Actins ; Animals ; Balkan Nephropathy ; Blotting, Western ; Cadherins ; Diet ; Epithelial Cells ; Fanconi Syndrome ; Glycosuria ; Hypokalemia* ; Kidney ; Macrophages ; Mice ; Potassium ; Proteinuria ; Rats* ; Sodium

Fanconi syndrome is a dysfunction of the proximal renal tubules that results in impaired reabsorption and increased urinary loss of phosphate and other solutes. The pathophysiology of drug-induced Fanconi syndrome is unclear. Here we report the case of a 36-year-old woman who presented with pain in multiple bones and proteinuria. She had a 7-year history of taking adefovir at 10 mg/day for chronic hepatitis B. Three years previously she had received surgery for a nontraumatic right femur neck fracture, after which she continued to complain of pain in multiple bones, and proteinuria, glycosuria, and phosphaturia were noted. The findings of a light-microscope examination of a renal biopsy sample were normal, but mitochondrial damage of the proximal tubules was evident in electron microscopy. Western blot analysis revealed that the level of serum fibroblast growth factor 23 (FGF23) was lower than in normal controls. After 2 months of treatment, hypophosphatemia and proximal tubular dysfunction were reversed, and serum FGF23 had normalized. This case suggests that direct mitochondrial damage in proximal tubules can cause drug-induced Fanconi syndrome associated with osteomalacia.
Adult ; Biopsy ; Blotting, Western ; Fanconi Syndrome* ; Female ; Femoral Neck Fractures ; Fibroblast Growth Factors ; Glycosuria ; Hepatitis B, Chronic ; Humans ; Hypophosphatemia ; Hypophosphatemia, Familial ; Kidney Tubules, Proximal ; Microscopy, Electron ; Mitochondria ; Osteomalacia* ; Proteinuria

BACKGROUND: Tenofovir disoproxil fumarate (TDF) is relatively safe, although renal toxicity has been reported. In Nigeria, there is insufficient data on renal toxicity among patients on TDF. This study assesses TDF-associated tubular dysfunction among human immunodeficiency virus (HIV) patients at a hospital in Nigeria. METHODS: In this cohort study, 104 adult HIV patients were recruited with a simple random technique from the outpatient clinic. Biochemical indices of renal function were estimated from serum and urine at the 16th and 24th week after an initial assessment at baseline. RESULTS: There were no significant differences in baseline proteinuria or glycosuria between TDF and non-TDF groups. Mean baseline urine and serum parameters did not differ significantly between the two groups (P > 0.05). In the TDF group, all urine parameters differed significantly between baseline and 24th week values (P < 0.001). After 16 weeks, mean urine phosphate and urine uric acid increased significantly (P < 0.05) by 2.97 mg/dL and 50.9 mg/dL, respectively, in the TDF group. The rise in mean urine glucose from baseline to the 24th week was more marked in the TDF than the non-TDF group (0.25 vs. 0.07 mmol/L). Higher mean differences in urine albumin were also recorded in the TDF group from baseline to the 24th week. CONCLUSION: Indicators of tubular dysfunction were markedly higher among patients on the TDF-based treatment regimen. Biomarkers of tubular dysfunction could be useful for detecting pre-symptomatic nephrotoxicity before marked reduction of glomerular filtration rate in HIV patients on TDF.
Adult ; Ambulatory Care Facilities ; Biomarkers ; Cohort Studies ; Fanconi Syndrome ; Glomerular Filtration Rate ; Glucose ; Glycosuria ; HIV* ; Humans* ; Nigeria* ; Proteinuria ; Renal Insufficiency, Chronic ; Tenofovir ; Uric Acid

Renal Fanconi syndrome (RFS) is caused by generalized proximal tubular dysfunction and can be divided into hereditary and acquired form. Adult-onset RFS is usually associated with drug toxicity or systemic disorders, and modern molecular genetics may explain the etiology of previous idiopathic cases of RFS. Here, we report the case of a 52-year-old woman with RFS whose etiology could not be identified. She presented with features of phosphaturia, renal glucosuria, aminoaciduria, tubular proteinuria, and proximal renal tubular acidosis. Her family history was unremarkable, and previous medications were nonspecific. Her bone mineral density was compatible with osteoporosis, serum intact parathyroid hormone level was mildly elevated, and 25(OH) vitamin D level was insufficient. Her blood urea nitrogen and serum creatinine levels were 8.4 and 1.19 mg/dL, respectively (estimated glomerular filtration rate, 53 mL/min/1.73 m²). Percutaneous renal biopsy was performed but revealed no specific renal pathology, including mitochondrial morphology. No mutation was detected in EHHADH gene. We propose the possibility of involvement of other genes or molecules in this case of adult RFS.
Acidosis, Renal Tubular ; Adult ; Biopsy ; Blood Urea Nitrogen ; Bone Density ; Creatinine ; Drug-Related Side Effects and Adverse Reactions ; Fanconi Syndrome ; Female ; Glomerular Filtration Rate ; Glycosuria, Renal ; Humans ; Hypophosphatemia, Familial ; Middle Aged ; Molecular Biology ; Osteoporosis ; Parathyroid Hormone ; Pathology ; Proteinuria ; Vitamin D

Adefovir dipivoxil (ADV) and tenofovir disoproxil fumarate (TDF) are nucleotide analogues used to treat chronic hepatitis B (CHB) infection. Nephrotoxicity associated with the use of these medications causes Fanconi syndrome, a rare condition involving generalized dysfunction of the proximal renal tubule causing impaired reabsorption of glucose, uric acid, and phosphate. Fanconi syndrome has been previously reported in patients with human immunodeficiency virus (HIV) or HIV-CHB coinfection treated with other antiretroviral therapies. However, it is rarely reported in patients with CHB monoinfection. We observed a case of Fanconi syndrome in a 61-year-old woman with CHB monoinfection and a history of long-term ADV therapy (42 months), followed by TDF treatment for 9 months. She presented with ankle pain and a tingling sensation in both lower extremities. Laboratory tests revealed hypokalemia, hypocalcemia, hypophosphatemia, hypouricemia, proteinuria, and glycosuria. This case illustrates the importance of recognizing Fanconi syndrome associated with nucleotide analogue treatment and the need to carefully observe symptoms and monitor renal function in these patients.
Ankle ; Coinfection ; Fanconi Syndrome* ; Female ; Glucose ; Glycosuria ; Hepatitis B, Chronic* ; Hepatitis, Chronic* ; HIV ; Humans ; Hypocalcemia ; Hypokalemia ; Hypophosphatemia ; Kidney Tubules, Proximal ; Lower Extremity ; Middle Aged ; Proteinuria ; Sensation ; Uric Acid

Familial renal glycosuria (FRG) is an inherited disorder characterized by persistent glycosuria in the absence of hyperglycemia. It is caused by mutations in the sodium-glucose co-transporter, leading to increase in the renal excretion of glucose and sodium. However, there have been no studies on the role of fasting and postprandial changes in the urinary sodium excretion in patients with FRG. We report a case of renal glycosuria, which was confirmed by a SLC5A2 mutation via gene sequencing, and compared the postprandial urinary glucose and sodium excretion. A 26-year-old man sometimes experienced glycosuria on routine screening; however, other laboratory findings were normal. His fasting and postprandial urinary glucose excretion levels were 295mg/dL and 2,170mg/dL, respectively. The fasting and postprandial urinary sodium excretion levels were 200mEq/L and 89mEq/L, respectively. In patients with FRG, excessive diuresis might be prevented by a compensatory mechanism that reduces postprandial sodium excretion.
Adult ; Diuresis ; Fasting ; Glucose ; Glycosuria* ; Glycosuria, Renal ; Humans ; Hyperglycemia ; Mass Screening ; Renal Elimination ; Sodium ; Sodium-Glucose Transport Proteins

Tubulointerstitial nephritis and uveitis (TINU) syndrome is a rare disease that comprises 4.7% of acute interstitial nephritis. With reno-ocular manifestations, TINU syndrome is accompanied by symptoms such as fever, fatigue, malaise, anorexia, vomiting, and arthralgia. TINU syndrome is reported mainly in children or adolescent girls, and it is rare in adults. Although TINU syndrome can present with multiple renal tubular defects, Fanconi syndrome characterized by generalized impairment of proximal tubular function, leading to renal glucosuria, hyperuricosuria, hyperphosphaturia, proximal renal tubular acidosis, and kaliuresis leading to hypokalemia, has rarely been described. We report a case of TINU syndrome with Fanconi syndrome in a 46-year-old HLA B27-positive Korean woman.
Acidosis, Renal Tubular ; Adolescent ; Adult ; Anorexia ; Arthralgia ; Child ; Fanconi Syndrome* ; Fatigue ; Female ; Fever ; Glycosuria, Renal ; Humans ; Hypokalemia ; Hypophosphatemia, Familial ; Middle Aged ; Nephritis, Interstitial* ; Rare Diseases ; Uveitis* ; Vomiting