Introduction: Since the breakout of COVID-19 in December 2019, the virus has already affected and taken millions of lives over the past year. There is still much to learn about this disease. It has been postulated that the human kidney is a potential pathway for COVID-19 due to the presence of the ACE2 receptors found in the surfaces of kidney cells. Some studies that demonstrated acute tubular necrosis and lymphocyte infiltration among post mortem COVID-19 patients, concluding that the virus could directly damage the kidney, increasing the risk of the development of Acute Kidney Injury (AKI) among patients with COVID-19. This study investigated the incidence and severity of AKI among hospitalized COVID-19 patients and the association of the degree of AKI with regards to the severity and outcomes of COVID-19 patients. Methods: This was a single-center cross-sectional study retrospective chart review of COVID-19 patients who developed AKI. Descriptive statistics were used to summarize the general and clinical characteristics of the patients. Frequency and proportion were used for categorical variables. Shapiro-Wilk test was used to determine the normality distribution of continuous variables. Continuous quantitative data that met the normality assumption was described using mean and standard deviation, while those that did not were described using median and range. Continuous variables which are normally distributed were compared using the One-way ANOVA, while those variables that are not normally distributed were compared using the Kruskal-Wallis H test. For categorical variables, the Chi-square test was used to compare the outcomes. If the expected percentages in the cells are less than 5%, Fisher's Exact Test was used instead. Results: A total of 1441 COVID-19 in-patients from March 1, 2020 to March 1, 2021 were reviewed, 59 of whom were excluded. Among the adults with COVID-19 who developed AKI, 60% were in stage I, 10% in stage II, and 30% in stage III. The incidence of AKI among COVID-19 in-patients at Makati Medical Center was 13.10% (95% CI 11.36% - 14.99%). Among the 181 patients, 79 (43.65%, 95% CI 36.30 - 51.20) had died. The mortality rate is 22.02% for Stage I, 50% for Stage II, and 85.19% for Stage III. The median length of hospital stay was 12 days, ranging from 1 day up to 181 days. Full renal recovery on discharge was observed only in one-third of the patients. It was observed in 44.95% of those in Stage I, 27.78% of those in Stage II, and 5.56% of those in Stage III. Conclusion The study demonstrated that the incidence of AKI in hospitalized COVID-19 patients was 13.1% (95% CI 11.36% - 14.99%), which was lower than previously reported. This could be attributed to the longer study period wherein, to date, we have a better understanding of the disease and had already established a standard of care for treatment for the disease attributing to the decreased incidence of AKI among COVID-19 patients than what was initially reported. The development of AKI has a direct correlation with the degree of infection. Among patients who developed AKI, 20% required renal replacement therapy. Overall development of AKI increases the risk of mortality among hospitalized COVID-19 patients. The stage of AKI has a direct correlation with regards to mortality and has an indirect relationship with regards to renal recovery.
Acute Kidney Injury ; COVID-19 ; Renal Replacement Therapy ; Mortality