Evaluation of the relationship between lung involvement and kidney damage in patients presenting with COVID-19 pneumonia

Coronavirus (2019-nCoV), which was detected in Wuhan,China, as the cause of severe pneumonia cases that could cause acute respiratory failure, spread all over the world within months, causing morbidity and mortality in millions of people at the end of 2019. In addition to causing pneumonic infiltrations, COVID- 19 affects many organs systemically. After the lungs, one of the most frequently involved organs are the kidneys. Since the development of acute renal damage in COVID-19 patients is directly related to the risk of morbidity and mortality, the detection of kidney involvement and risk factors gain importance. Although the etiology of kidney involvement is still not clear, it is thought to be multifactorial. The virus has a direct cytopathic effect on renal tubular epithelium and podocytes through the ACE-2 receptor, resulting in collapsing glomerulopathy and protein leakage from Bowman's capsule. Another cause of acute kidney injury is glomerulopathies that develop after viral infection. In the foreground are focal segmental glomerulosclerosis and membranous glomerulopathy. Another factor thought to have a role in the etiology is direct damage to the kidney due to virus-derived specific immunological mechanisms and immunocomplex accumulations. It was established that a relationship between the degree of COVID-19 pneumonia and the development of acute kidney injury in several studies. Therefore, in this study, we aimed to evaluate the relationship between lung involvement and kidney damage in patients presenting with COVID-19 pneumonia. The study included 341 patients who met the appropriate criteria and applied to our hospital with the diagnosis of COVID-19 pneumonia, whose diagnosis was confirmed by PCR Assay, between April 2020 and November 2020 at Gazi University Medical Faculty Hospital. Based on our outcomes; it was determined that AKI developed according to the KDIGO criteria in 152 (44.6%) patients, hematuria was present in 149 (43.7%) patients, and proteinuria was present in 201 (58.9%) patients. In 256 (75.1%) patients, at least one of these three (hematuria, proteinuria, and elevated creatinine) findings was found to be present. It was determined that 38 (11.1%) patients died during hospitalization. When we divide the patients into groups according to the severity of pneumonia; according to lung CT, the rate of development of AKI is higher in patients with extensive pneumonia, serum creatinine and BUN levels are higher, GFR is lower, and the incidence of proteinuria and death is higher. In addition, a correlation was found between the severity of pneumonia involvement in the lung and AKI, serum creatinine, BUN, GFR and proteinuria. In the multivariate analysis, it was determined that a high percentage of lung involvement was associated with the development of AKI. It was stated that the severity and prevalence of pulmonary tomography findings, which are widely used during hospitalization in patients followed up in the hospital due to COVID-19, may be a prediction for the development of AKI and the severity of AKI, supportive treatment and additional nephrotoxic factors in patients in the risk group in terms of possible renal involvement or development of AKI. It must be taken into attention. It is thought that controlled fluid support to avoid hypovolemia, avoidance of nephrotoxic drugs, regular monitoring of serum creatinine and urine output, and hemodynamic monitoring can prevent the clinical worsening of the patients.