COVID-19 and kidney: role of SARS-CoV-2 infection in the induction of renal damage.

OBJECTIVE

SARS-CoV-2 causes acute respiratory disease, interstitial and alveolar pneumonia, and involves numerous organs and systems such as the kidney, heart, digestive tract, blood, and nervous system. We aimed to evaluate the incidence of renal manifestations in patients diagnosed with COVID-19 infection.

PATIENTS AND METHODS

We performed a monocentric, cross-sectional, observational study, conducted on 114 patients with SARS-CoV-2. Clinical and laboratory parameters [renal function, serum electrolytes, inflammatory state, blood gas analysis, Interleukin 6 (IL-6) and urinalysis] were evaluated. The same values were checked out after two months (T1), however after negativization.

RESULTS

We enrolled 114 patients (59 males) with a mean age of 63.8 ± 13.9 years. We found hematuria in 48 patients (55.8%), proteinuria in 33 patients (38.4%), leukocyturia in 61 patients (70.9%), acute kidney injury (AKI) in 28 patients (24.6%), AKI in chronic kidney disease (CKD) in 24 patients (21.1%). Moreover, we found a significant increase of inflammatory indexes as C Reactive Protein (CRP), lactic dehydrogenase (LDH), alpha 1 and alpha 2 globulins with a subsequent reduction at T1 (p = 0.016, p < 0.001, p = 0.005, p = 0.007; respectively). Hemoglobin and erythrocyte values significantly decreased (p < 0.001, p = 0.003, respectively), and we found lymphopenia (p < 0.001). Also, we found elevated levels of the D-Dimer (p < 0.001) and a significant increase in the International Normalized Ratio (INR) (p = 0.038). We also showed a significant improvement after negativization in oxygen partial pressure (p = 0.001) and oxygen saturation (p < 0.001) and a significant increase in pH (p = 0.018) and bicarbonate concentration (p = 0.042). Moreover, we found a significant increase in IL-6 (p = 0.004). Also, we reported mild hyponatremia and hypokalemia with subsequent significant recovery (p < 0.001, p < 0.001, respectively) and mild hypochloremia with a recovery to the limits of statistical significance (p = 0.053). At the entrance, we found an increase in serum glucose with a significant reduction during recovery (p < 0.001).

CONCLUSIONS

The prevalence of AKI and/or CKD and/or abnormal urinalysis in patients diagnosed with COVID-19 on admission seems to be high and appears as a negative prognostic factor. Urinalysis appears to be very useful in unveiling the potential kidney impairment of COVID-19 patients; therefore, urinalysis could be used to reflect and predict the disease severity. We also recommend a careful evaluation of metabolic alterations, inflammatory states, and electrolytic disorders in COVID-19 patients.