The relationship between serum creatinine and estimated glomerular filtration rate: implications for clinical practice

Plasma levels of asymmetric dimethylarginine in patients with biopsy-proven nonalcoholic fatty liver disease

Asymmetric (ADMA) and symmetric dimethylarginine (SDMA) are produced by breakdown of proteins that have been methylated posttranslationally at an arginine residue. Plasma levels of ADMA are elevated in insulin resistance states. Nonalcoholic fatty liver disease (NAFLD) is associated with insulin resistance and varying degrees of hepatic dysfunction. Because ADMA is metabolized in the liver, we hypothesized that ADMA levels will be high in patients with NAFLD as a consequence of hepatic dysfunction and insulin resistance. Plasma levels of ADMA, SDMA, total homocysteine, glucose, and insulin were measured in nondiabetic patients with biopsy-proven NAFLD (11 steatosis and 24 nonalcoholic steatohepatitis) and 25 healthy subjects. Plasma ADMA levels were significantly higher (P = .029) in patients with biopsy-proven NAFLD (0.43 ± 0.21 μmol/L) compared with controls (0.34 ± 0.10 μmol/L). However, when adjusted for insulin resistance (homeostasis model assessment), the difference between 2 groups was not evident. Plasma SDMA levels were similar in all 3 groups. Plasma levels of ADMA were positively correlated with plasma total homocysteine levels (P = .003). Plasma levels of SDMA were negatively correlated with estimated glomerular filtration rate (P = .016) and positively correlated with plasma total homocysteine levels (P = .003). The ratio of ADMA/SDMA was positively correlated with body mass index (P = .027). Elevated plasma concentrations of ADMA in biopsy-proven NAFLD were primarily related to insulin resistance. Hepatic dysfunction in NAFLD does not appear to make significant contribution to changes in plasma methylarginine levels.

Referral of patients with kidney impairment for specialist care in a developing country of sub-Saharan Africa

AIM

The aim of this study was to assess the referral pattern of patients with kidney impairment in Cameroon.

METHODS

Medical files of patients received at the out-patients department of nephrology from January 2001 to December 2003 at the Yaounde General Hospital were reviewed. Individual information recorded included age, sex, and referral sources. Data on etiologic and co-morbidity factors, clinical signs of CRF, anthropometric measurements, blood pressure, and biological variables were recorded. Patients were staged for kidney damage in three groups following an adaptation of the Kidney Disease Outcome Quality Initiative (KDOQI) guide recommendations, using the creatinine clearance derived from the Cockroft-Gault equation.

RESULTS

Of the 183 patients received during the study period, 140 (77.8%) fulfilled the entry criteria. Men (70%) were more represented, and mean age was 50.19 +/- 1.07 years. Hypertension (62.1%) and diabetes mellitus (26.4%) were the most frequent risk factors. There was no major difference between men and women for most clinical and biological variables. Patients were referred mostly by cardiologist (31.4%) and general practitioners (29.3%). Late referral (GFR <30 mL/min) encompassed 82.8% of participants. Regardless of the referral source, the overall trend was toward late referral. Clinical and biological profiles worsen with advanced stage of kidney impairment. In general, management of patients prior to referral was poor.

CONCLUSIONS

This study has revealed the disconcerting high rate of late referral to nephrologists in this context. Many potential factors can account for this observed pattern, and it is worth investigating to improve referral and outcomes of patients with kidney diseases in Cameroon.