ABSTRACT
Background: Fractional excretion of urinary sodium (FENa) is a widely utilized clinical test to evaluate acute kidney injury (AKI). A low FENa (<1%) is deemed consistent with prerenal azotemia and inconsistent with acute tubular injury (ATI). Muddy brown granular casts (MBGC) on microscopic examination of urinary sediment (MicrExUrSed) are highly suggestive of ATI. We hypothesized that there is poor concordance between the presence of MBGC and FENa in ATI. Methods: We conducted a prospective observational study in patients with AKI seen during inpatient consultation. We extracted patients who underwent assessment of percentage of low power fields (LPFs) with MBGC by MicrExUrSed and concomitant measurement of FENa. Diagnostic concordance between MBGC and FENa and their individual prognostic value were examined. Results: Our cohort included 270 patients, 111 (41%) of whom were women. Median age was 61 years (range 27-92 years), and median serum creatinine was 3.7 mg/dl ( range1.2-22.0 mg/dl). MBGC were found in 49% (133/270). FENa <1% (inconsistent with ATI) was found in 50/133 (38%), 38/115 (33%), and 16/45 (36%) of those with >0%, ≥10%, and ≥50% LPFs with MBGC, respectively. Concordance between FENa and MBGC for ATI diagnosis was deemed fair (estimated κ-coefficient=0.2), and poor (κ=-0.11) within a subgroup of patients with preexisting chronic kidney disease (n=139). In patients with biopsy-proven ATI (n=49), MBGC had 100% specificity and 100% positive predictive value for ATI. MBGC were associated with greater risk for ≥50% increase in creatinine from baseline at discharge (acute kidney disease [AKD]). Conclusions: About two of five patients with MBGC identified by MicrExUrSed presented with FENa <1%. Presence of MBGC was consistent with ATI, as verified by biopsy, and were predictive of AKD. These data suggest that the sole reliance in low FENa to exclude ATI should be abandoned, and MicrExUrSed should be pursued for AKI diagnosis.
Subject(s)
Acute Kidney Injury , Sodium , Acute Kidney Injury/diagnosis , Adult , Aged , Aged, 80 and over , Creatinine , Female , Humans , Kidney Function Tests , Male , Middle Aged , UrinalysisABSTRACT
OBJECTIVE: To critically analyze the existing randomized controlled trials (RCTs) on the clinical, economic, and psychological implications of maggot debridement therapy (MDT). DATA SOURCES: An exhaustive literature search for English-language publications was conducted using MEDLINE, EMBASE, and PubMed. STUDY SELECTION: Keywords used for the search were based on the PICO (Population, Intervention, Comparison, Outcome) framework. The titles, abstracts, and relevant full-text articles were screened. Seven RCTs were selected after applying the inclusion and exclusion criteria. DATA EXTRACTION: Data pertaining to the primary and secondary outcomes of each study were extracted. DATA SYNTHESIS: The data extracted were evaluated and categorized into clinical, economic, and psychological outcomes pertaining to MDT. A judicious evaluation of these outcomes was made, and the following conclusions were drawn. CONCLUSIONS: There exists heterogeneity in the extant RCTs, but MDT appears to be effective for a quick early debridement. For diabetic foot ulcers, MDT improves debridement, controls infection, and enhances wound healing. In chronic peripheral vascular disease ulcers, it aids in early debridement, but the final outcome is equivocal. Further robust integrated health economic and parallel qualitative assessment studies are recommended to understand the cost-effectiveness and patient acceptability and experience.
