RESUMEN
Acute rhabdomyolysis (AR) leading to acute kidney injury has many underlying etiologies, however, when the primary trigger is exercise, the most usual underlying cause is either a genetic muscle disorder or unaccustomed intense exercise in a healthy individual. Three adult men presented with a history of exercise intolerance and episodes of acute renal impairment following intense exercise, thought to be due to AR in the case of two, and dehydration in one. The baseline serum CK was mildly raised between attacks in all three patients and acutely raised during attacks in two of the three patients. Following referral to a specialized neuromuscular centre, further investigation identified very low serum urate (<12 umol/L). In all three men, genetic studies confirmed homozygous mutations in SLC2A9, which encodes for facilitated glucose transporter member 9 (GLUT9), a major regulator of urate homeostasis. Hereditary hypouricaemia should be considered in people presenting with acute kidney injury related to intense exercise. Serum urate evaluation is a useful screening test best undertaken after recovery.
Asunto(s)
Lesión Renal Aguda , Defectos Congénitos del Transporte Tubular Renal , Rabdomiólisis , Cálculos Urinarios , Masculino , Adulto , Humanos , Ácido Úrico , Cálculos Urinarios/genética , Cálculos Urinarios/complicaciones , Cálculos Urinarios/diagnóstico , Defectos Congénitos del Transporte Tubular Renal/genética , Defectos Congénitos del Transporte Tubular Renal/complicaciones , Defectos Congénitos del Transporte Tubular Renal/diagnóstico , Proteínas Facilitadoras del Transporte de la Glucosa/genética , Lesión Renal Aguda/genética , Mutación , Rabdomiólisis/genética , Rabdomiólisis/complicacionesRESUMEN
We aimed to describe temporal trends in the prevalence and characteristics of hypouricaemia. We analysed medical check-up and administrative claims data to calculate hypouricaemia prevalence from 2009 to 2019. Then, using data from 2018 to 2019, we compared the characteristics of individuals with and without hypouricaemia. We also compared the characteristics of those with lower (serum uric acid [sUA] ≤ 1.0 mg/dL) and higher (1.0 mg/dL < sUA ≤ 2.0 mg/dL) hypouricaemia. In total, 1,600,290 subjects underwent medical check-ups. The age-adjusted prevalence of hypouricaemia remained stable at 0.2% overall (men, 0.1%; women, 0.4%). We identified 1704 subjects with hypouricaemia (598 men and 1106 women) among 796,508 subjects and studied their characteristics. The proportion of most pre-existing diseases, including urinary stones, was lower in those with hypouricaemia than in those without hypouricaemia. Cardio-metabolic diseases and Parkinson's disease were more frequent in men with hypouricaemia than those without hypouricaemia. Women with hypouricaemia tended to have healthier characteristics. Hypertension and dyslipidaemia were more common in the lower hypouricaemia group than in the higher hypouricaemia group. The age-adjusted prevalence of hypouricaemia remained stable over 10 years. The characteristics of hypouricaemia subjects appear to differ between the sexes and between lower and higher hypouricaemia groups. Key Points ⢠The prevalence of hypouricaemia remained almost unchanged over 10 years. ⢠Cardio-metabolic diseases and Parkinson's disease were more frequent in men with hypouricaemia than in those without hypouricaemia. ⢠Subjects with extremely low serum urate (sUA ≤ 1.0 mg/dL) appeared to have higher cardio-metabolic disease risks. ⢠Routine checks of sUA could be useful in screening or predicting these conditions.
Asunto(s)
Hipertensión , Enfermedad de Parkinson , Errores Innatos del Metabolismo de la Purina-Pirimidina , Cálculos Urinarios , Niño , Femenino , Humanos , Hipertensión/epidemiología , Masculino , Prevalencia , Ácido ÚricoRESUMEN
OBJECTIVES: Hyperuricaemia is recognized as an independent risk marker for cardiovascular and renal diseases. However, uric acid is a powerful free-radical scavenger, and the optimal level of serum uric acid (SUA) determining outcomes is unknown. This study explored whether interventional treatments for excessive SUA reduction were harmful and what constituted the optimal lowering of SUA levels for the prevention of events in patients with asymptomatic hyperuricaemia. METHODS: This was a post hoc analysis of a randomized trial (Febuxostat for Cerebral and CaRdiorenovascular Events PrEvEntion StuDy [FREED]) in which 1070 older patients with asymptomatic hyperuricaemia were enrolled and allocated to febuxostat (n = 537) or non-febuxostat treatment group (n = 533). We assessed the relationship between the endpoint (withdrawal or study completion) SUA levels and clinical outcomes. Primary endpoint was defined as a composite of all-cause mortality, cerebral and cardiorenovascular events. RESULTS: In the febuxostat group, patients achieving SUA levels ≤4 mg/dl (hazard ratio: 2.01 [95% CI: 1.05, 3.87]), >4 to ≤5 mg/dl (2.12 [1.07, 4.20], >6 to ≤7 mg/dl (2.42 [1.05, 5.60]), and >7 mg/dl (4.73 [2.13, 10.5]) had significantly higher risks for a primary composite event than those achieving SUA levels >5 to ≤6 mg/dl (P = 0.003 [log-rank test]). This J-shaped relationship applied to patients with renal impairment (P = 0.007 [Gray's test]) and was not significant in the non-febuxostat treatment group (P = 0.212 [log-rank test]). CONCLUSION: Optimal SUA level by febuxostat treatment is 5-6 mg/dl for reducing all-cause mortality, cerebral, cardiovascular and renal events. Excessive SUA reduction may be harmful in older hyperuricaemic populations. TRIAL REGISTRATION: ClinicalTrial.gov, https://clinicaltrials.gov, NCT01984749.
Asunto(s)
Gota , Hiperuricemia , Anciano , Febuxostat/uso terapéutico , Gota/tratamiento farmacológico , Supresores de la Gota/uso terapéutico , Humanos , Hiperuricemia/complicaciones , Hiperuricemia/tratamiento farmacológico , Resultado del Tratamiento , Ácido ÚricoRESUMEN
OBJECTIVES: Up to 0.3% of Japanese have hypouricaemia. Most cases appear to result from a hereditary disease, renal hypouricaemia (RHUC), which causes exercise-induced acute kidney injury and urolithiasis. However, to what extent RHUC accounts for hypouricaemia is not known. We therefore investigated its frequency and evaluated its risks by genotyping a general Japanese population. METHODS: A cohort of 4993 Japanese was examined by genotyping the non-functional variants R90H (rs121907896) and W258X (rs121907892) of URAT1/SLC22A12, the two most common causative variants of RHUC in Japanese. RESULTS: Participants' fractional excretion of uric acid and risk allele frequencies markedly increased at lower serum uric acid (SUA) levels. Ten participants (0.200%) had an SUA level ≤2.0 mg/dl and nine had R90H or W258X and were likely to have RHUC. Logistic regression analysis revealed these URAT1 variants to be significantly and independently associated with the risk of hypouricaemia and mild hypouricaemia (SUA ≤3.0 mg/dl) as well as sex, age and BMI, but these URAT1 variants were the only risks in the hypouricaemia population (SUA ≤2.0 mg/dl). W258X was only a risk in males with SUA ≤3.0 mg/dl. CONCLUSION: Our study accurately reveals the prevalence of RHUC and provides genetic evidence for its definition (SUA ≤2.0 mg/dl). We also show that individuals with SUA ≤3.0 mg/dl, especially males, are prone to RHUC. Our findings will help to promote a better epidemiological understanding of RHUC as well as more accurate diagnosis, especially in males with mild hypouricaemia.
Asunto(s)
Transportadores de Anión Orgánico/genética , Proteínas de Transporte de Catión Orgánico/genética , Defectos Congénitos del Transporte Tubular Renal/genética , Cálculos Urinarios/genética , Femenino , Variación Genética , Genotipo , Humanos , Japón/epidemiología , Masculino , Defectos Congénitos del Transporte Tubular Renal/epidemiología , Cálculos Urinarios/epidemiologíaRESUMEN
Acute kidney injury with severe loin pain and patchy renal ischaemia after anaerobic exercise (ALPE) is a rare clinical syndrome. ALPE has predominantly been described in Japanese and Korean populations to date. Many cases and most recurrent examples are associated with renal hypouricaemia. We describe a 28-year-old New Zealand European male without renal hypouricaemia who developed recurrent ALPE whilst performing elite-level sport. Avoiding elite-level anaerobic exercise was successful at preventing further episodes. This report confirms the first known case of ALPE in a New Zealand European male and raises the possibility that ALPE is an under-recognized condition. Long-term outcomes of recurrent ALPE remain unclear, and preventative strategies should be implemented to preserve renal function. Avoiding intense anaerobic exercise is an effective preventative strategy.
RESUMEN
We report a rare case of nephrocalcinosis caused by hereditary renal hypouricaemia 3 months after kidney transplantation. A 41-year-old man who underwent living-related kidney transplantation from his father was admitted to our hospital for a protocol biopsy; he had a serum creatinine (S-Cr) of 1.37 mg/dL and no proteinuria. Histologically, there was no evidence of rejection or calcineurin inhibitor toxicity, although scattered nephrocalcinosis was observed in the distal tubules. Perioperatively, the patient had a serum uric acid (S-UA) of 1.9 mg/dL with a fractional excretion of uric acid (FEUA) of 29% (normal, <10%) and UA clearance of 26.8 mL/min (normal, 7.3-14.7 mL/min) 3 days after kidney transplantation. The donor also had a relatively low S-UA of 2.4 mg/dL and high FEUA of 10.3%. Subsequent DNA direct sequencing followed by restriction fragment length polymorphism revealed that both the recipient's and donor's urate transporter 1 (URAT1) gene had a heterozygous nonsense mutation in exon 5 (C889T). Further, the immunoreactivity of antibodies for the C terminus of URAT1 revealed a partial deletion. De Galantha and von Kossa staining revealed that the nephrocalcinosis was due to urate crystals and calcium stones. Therefore, we diagnosed hereditary renal hypouricaemia. We directed the patient to avoid hard exercise, drink plenty of water, and alkalize the urine. The 1-year follow-up allograft biopsy showed no evidence of nephrocalcinosis in the distal tubules. This is the first report of nephrocalcinosis in the distal tubules as a diagnostic clue to hereditary renal hypouricaemia. We also review the related literature.