Ricardo Heguilen

Folic acid 5 or 15 mg/d similarly reduces plasma homocysteine in patients with moderate-advanced chronic renal failure.

Background:  Hyperhomocysteinaemia is an independent risk factor for cardiovascular disease with a remarkable prevalence in patients with chronic renal failure (CRF). Low doses of folic acid (FA) with or without vitamin B6 and B12 has been shown to effectively reduce plasma homocysteine (Hcy). The aim of this study was to compare the short‐term effects of two different oral doses of FA (5 vs 15 mg/d) on plasma Hcy levels in subjects suffering from moderate–severe CRF.

Renal response to an acute protein challenge in pregnant women with borderline hypertension

Background:  The renal reserve (RR), assessed after an oral protein challenge or the intravenous administration of amino acids, is still present in healthy pregnant women (NP), although resting glomerular filtration rate (GFR) and renal plasma flow (RPF) increase progressively throughout normal gestation. No studies have addressed this issue in hypertensive gravidas; the aim of this trial was to evaluate renal response to an acute protein load (PL) in NP and pregnant women with borderline hypertension (HP).

Ca2+Mg3+-ATPase activity in erythrocyte membranes in hypercalciuric nephrolithiasic patients

SUMMARY: Ca2+Mg2+ATPase is an enzyme involved in calcium transport across biological membranes. In order to determine its possible role in the pathogenesis of calcium nephrolithiasis, we assessed Ca2+Mg2+‐ATPase activity in erythrocyte membranes from 18 hypercalciuric (HC) nephrolithiasic patients (nine with absorptive hypercalciuria (AHC), nine with renal hypercalciuria (RHC)) and eight normocalciuric healthy controls (C). Participants took no medication for at least 3 months before the study and remained on a diet containing approximately 25 mmol of calcium per day for 14 days. Pump activity was measured in calmodulin‐free red blood cell membranes and expressed in umol of phosphate released per mg of membrane protein per h. There were statistically significant differences in pump activity between groups (1.43±0.07; 1.93±0.1; 1.65±0.06; C, AHC, RHC, respectively, P < 0.005 (three groups) and P < 0.02 AHC versus RHC. Enzyme activity was positively correlated with 24‐h urinary calcium excretion (r = 0.64, P < 0.01) in HC patients; no such relationship was found in C. In conclusion, erythrocyte membrane Ca2+Mg2+ATPase activity is increased in HC. Differences in enzyme activity between AHC and RHC may reflect different degrees of a single generalized epithelial calcium transport disturbance.

When arthralgia is not arthritis

The presence of distal extremity pain in children and adolescents usually triggers the search of rheumatologic diseases without considering non-rheumatologic causes of joint pain. Approaching distal extremity pain with a complete differential diagnosis, including non-rheumatologic entities, may hasten diagnosis, thus decreasing cost and aiding in earlier initiation of appropriate therapy. To present a case of a patient who after years of work up of arthralgia, which was actually attributed to rheumatologic causes, had an inherited metabolic disease. A 32-year-old male presented to the clinic with complaints of distal pain in his four limbs, predominantly in the hands, since he was 8 years. After 6 years of consultation in various pediatric centers, he was diagnosed with growing pains. At the age of 15 years, laboratory investigations began targeting rheumatologic causes of his symptomatology, and after 9 years, the diagnosis of chronic kidney disease of unknown etiology was made. Because of the constellation of signs and symptoms and his family history, an analysis of α-galactosidase A enzyme activity was conducted and Fabry disease was confirmed. Rheumatologists and immunologists may be the first encounter patients with Fabry disease. Thus, if Fabry disease is not considered at the differential diagnosis, an opportunity is missed for early initiation of a therapy.