Metabolites related to eGFR: Evaluation of candidate molecules for GFR estimation using untargeted metabolomics.

BACKGROUND: Metabolomics can be used to identify novel metabolites related to renal function and that could therefore be used for estimating GFR. We evaluated metabolites replicated and related to eGFR in 3 studies (CKD and general population). METHODS: Metabolomics was performed by GC-MS. The Progredir Cohort (n = 454, class 3 and 4 CKD) was used as the derivation study and adjusted linear regression models on eGFR-CKDEPI were built. Bonferroni correction was applied for selecting metabolites to be independently validated in the Diabetic Nephropathy Study (n = 56, macroalbuminuric DN) and in the Baependi Heart Study (BHS, n = 1145, general population). RESULTS: In the Progredir Cohort, 72 metabolites where associated with eGFR. Of those, 11 were also significantly associated to eGFR in the DN Study and 8 in the BHS. Four metabolites were replicated and significantly associated to eGFR in all 3 studies: d-threitol, myo-inositol, 4-deoxierythronic acid and galacturonic acid. In addition, pseudouridine was strongly correlated to eGFR only in the 2 CKD populations. CONCLUSIONS: Our results demonstrate metabolites that are potential biomarkers of renal function: d-threitol, myo-inositol, 4-deoxierythronic acid, galacturonic acid and pseudouridine. Further investigation is needed to determine their performance against otherwise gold-standard methods, most notably among those with normal eGFR.

Hypovitaminosis D in medical inpatients.

BACKGROUND: Vitamin D deficiency is a major risk factor for bone loss and fracture. Although hypovitaminosis D has been detected frequently in elderly and housebound people, the prevalence of vitamin D deficiency among patients hospitalized on a general medical service is unknown. METHODS: We assessed vitamin D intake, ultraviolet-light exposure, and risk factors for hypovitaminosis D and measured serum 25-hydroxyvitamin D, parathyroid hormone, and ionized calcium in 290 consecutive patients on a general medical ward. RESULTS: A total of 164 patients (57 percent) were considered vitamin D-deficient (serum concentration of 25-hydroxyvitamin D, < or = 15 ng per milliliter), of whom 65 (22 percent) were considered severely vitamin D-deficient (serum concentration of 25-hydroxyvitamin D, <8 ng per milliliter). Serum 25-hydroxyvitamin D concentrations were related inversely to parathyroid hormone concentrations. Lower vitamin D intake, less exposure to ultraviolet light, anticonvulsant-drug therapy, renal dialysis, nephrotic syndrome, hypertension, diabetes mellitus, winter season, higher serum concentrations of parathyroid hormone and alkaline phosphatase, and lower serum concentrations of ionized calcium and albumin were significant univariate predictors of hypovitaminosis D. Sixty-nine percent of the patients who consumed less than the recommended daily allowance of vitamin D and 43 percent of the patients with vitamin D intakes above the recommended daily allowance were vitamin D-deficient. Inadequate vitamin D intake, winter season, and housebound status were independent predictors of hypovitaminosis D in a multivariate model. In a subgroup of 77 patients less than 65 years of age without known risk factors for hypovitaminosis D, the prevalence of vitamin D deficiency was 42 percent. CONCLUSIONS: Hypovitaminosis D is common in general medical inpatients, including those with vitamin D intakes exceeding the recommended daily allowance and those without apparent risk factors for vitamin D deficiency.

Atheroembolic renal failure after invasive procedures. Natural history based on 52 histologically proven cases.

Atheromatous plaque material containing cholesterol crystals may dislodge and cause distal ischemia. To characterize atheroembolic renal failure, we retrospectively evaluated all patients at the Massachusetts General Hospital from 1981 to 1990 with both renal failure and histologically proven atheroembolism after angiography or cardiovascular surgery. Over the 10-year period, 52 patients were identified. They tended to be elderly men with a history of hypertension (81%), coronary artery disease (73%), peripheral vascular disease (69%), and current smoking (50%). Within 30 days of their procedure, only 50% of patients had cutaneous signs of atheroembolism, and 14% had documented blood eosinophilia. Urinalysis was often abnormal. Hemodynamically unstable patients died shortly after their procedure, yet renal function in the remainder continued to decline over 3 to 8 weeks. Patients who received dialysis had a higher baseline serum creatinine than those who did not (168 +/- 44 mumol/L versus 133 +/- 18 mumol/L, p = 0.02), with dialysis starting a median of 29 days after the procedure. Patients with renal failure due to atheroembolism alone, as opposed to multiple renal insults, were more likely to recover renal function (24% versus 3%, p = 0.03) and had a lower risk of death during the 6 months after their procedure (log-rank p = 0.002). Renal failure due to procedure-induced AE is characterized by a decline in renal function over 3 to 8 weeks. This time course is not consistent with most other iatrogenic causes of renal failure, such as radiocontrast or nephrotoxic medications, which present earlier and often resolve within 2 to 3 weeks after appropriate intervention.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute compartment syndrome in a hypothyroid patient.

Acute compartment syndrome (ACS) is caused by conditions that either decrease the size of the compartment of increase the content of the compartment. Intracompartmental pressures are raised, thereby initiating a sequence of events that results in myoneural injury. Although limb trauma is the most common and well-organized etiology of ACS, the cause is frequently not readily apparent. Thyroid disease is not a commonly recognized cause of ACS; only one case of ACS associated with hypothyroidism has been previously reported. We now describe a second case of ACS in a patient with severe hypothyroidism and discuss the possible pathogenesis of this association.

Gonococcal septic arthritis of the hip.

We describe a patient with a Neisseria gonorrhoeae monoarthritis of the hip. Treatment with intravenous ceftriaxone, oral doxycycline, and repeated fluoroscopic needle aspirations resulted in a complete recovery of function without residual deficit. Gonococcal monoarthritis of the hip is rare. Gonococcal hip infections appear to respond well to antibiotics and drainage by arthrocentesis. This differs from hip infections caused by other bacteria where joint damage is common and where the recommended initial treatment is open surgical drainage.