Saudi Journal of Kidney Diseases and Transplantation

: 2013  |  Volume : 24  |  Issue : 4  |  Page : 813--815

Clinical characteristics and outcomes of patients with acute kidney injury: A single-center study

Nadeeka Rathnamalala 
 430, Danny Hettiarachchi Mawatha, Kaduwela Road, Battaramulla, Sri Lanka

Correspondence Address:
Nadeeka Rathnamalala
430, Danny Hettiarachchi Mawatha, Kaduwela Road, Battaramulla
Sri Lanka

How to cite this article:
Rathnamalala N. Clinical characteristics and outcomes of patients with acute kidney injury: A single-center study.Saudi J Kidney Dis Transpl 2013;24:813-815

How to cite this URL:
Rathnamalala N. Clinical characteristics and outcomes of patients with acute kidney injury: A single-center study. Saudi J Kidney Dis Transpl [serial online] 2013 [cited 2022 Jan 21 ];24:813-815
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Full Text

To the Editor,

Acute kidney injury (AKI) is a cause of considerable morbidity and mortality among hospitalized patients. [1],[2],[3] It presents with a spectrum of severity and is an important cause of persistent renal dysfunction. [4],[5] The spectrum of the disease has now been defined with the use of two classification systems: Risk Injury Failure Loss End-Stage Renal Failure (RIFLE) criteria and Acute Kidney Injury Network (AKIN) criteria. [6],[7]

The use of these classification systems has made a uniform diagnosis possible. The incidence and demographic patterns of AKI in Sri Lanka are largely unknown due to the lack of published data. Studies elsewhere have shown a dominance of advanced age and co-morbid disease among patients with AKI, with more than 50% requiring renal replacement therapy (RRT). [3],[8],[9]

We conducted a cross-sectional study on patients referred for nephrology care over a period of four months. Data from the enrolled patients were extracted from their medical records using a data sheet. We defined AKI according to the RIFLE classification using both the urine output and the serum creatinine criteria. [6] Baseline renal function was defined as the lowest serum creatinine (SCr) value within the past three months as seen in the medical records. For patients whose previous value was not available, the baseline SCr was estimated by solving the Modification of Diet in Renal Disease (MDRD) equation, assuming a glomerular filtration rate of 75 mL/min/1.73 m 2 as recommended by the Acute Dialysis Quality Initiative (ADQI) Working Group. [6] Sepsis was defined according to the definitions of the American College of Chest Physicians/ Society of Critical Care Medicine. [10]

Outcomes were measured as complete recovery when the patients' SCr level dropped within 120% of baseline on discharge; partial recovery if SCr at discharge was 121-150% of baseline; and non-recovery if SCr at discharge was greater than 150% of baseline or if the patient was still receiving RRT. [11]

We enrolled 68 patients over a period of four months. The patient characteristics are shown in [Table 1]. The mean age was 49 years (±17.6), 73.5% were males, the mean body mass index (BMI) was 20.26 and 50% of the study population had pre-existing co-morbid disease. The etiologies identified among the participants are shown in [Table 2].{Table 1}{Table 2}

Sepsis (41.2%) was the most common cause for AKI and leptospirosis (29.4%) was the second most common cause for the same. The various sources of sepsis are shown in [Figure 1]. The source was largely unidentified, but urinary tract infection was the leading cause among those that were identified.{Figure 1}

Fifty-eight patients (85.3%) required RRT, with 46 patients (79.32%) receiving hemodialysis and 12 patients (20.68%) receiving acute peritoneal dialysis. Twenty patients (29.4%) made complete recovery while 28 patients (41.2%) made partial recovery; the mortality rate was 24%. Of the patients who made complete recovery, 70% were below the age of 55 years compared with 30% who were over 55 years (P = 0.13). The presence of co-morbidities was associated with a worse outcome, with only 5.9% patients achieving complete recovery (P < 0.01). None of the patients with pre-morbid diabetes mellitus made a complete recovery (P <0.01).

The finding of sepsis being the most common cause of AKI in our study is in keeping with many other studies. [3],[12],[13] Additionally, many studies have also shown a linear relationship between the severity of sepsis and the outcome of AKI. [14] In our study, the presence of co-morbidities such as diabetes mellitus and hypertension was associated with a poor outcome. Among our study population, 50% had preexisting co-morbid diseases while higher rates have been reported elsewhere. These studies also observed a poorer outcome in those with associated co-morbidity. [3],[13],[15]

Chances of complete recovery were less in patients with advanced age. Epidemiological studies show that the incidence of AKI is higher among the elderly and that these patients carry a higher incidence of occurrence of ESRD as well as higher mortality following AKI. [16] Aging kidneys undergo structural and functional changes that decrease their auto-regulatory capacity, which may explain the higher incidence in the elderly. [17] They may have undetected underlying chronic kidney disease, which may make them more susceptible to further damage and may explain why SCr, which is used as the marker to assess recovery, may not fall within the expected limits.

Our study suggests that sepsis remains the most common cause of AKI and leptospirosis remains an important cause of AKI in Sri Lanka. Older age and the presence of co-morbidities predicted a poorer outcome.


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