MINIMAL CHANGE DISEASE SECONDARY TO SARS-COV-2 (COVID-19) INFECTION: A REPORT OF 2 CASES AND REVIEW OF RELATED LITERATURE

ABSTRACT

BACKGROUND AND AIMS: The COVID-19 pandemic has brought to the forefront a wide spectrum of renal injuries that included glomerulopathies, some of which were recently highlighted in various case reports. These consist of focal and segmental glomerulosclerosis (FSGS) and minimal change disease (MCD).1 These changes were found among seemingly vulnerable populations such as the African American and Caucasian ethnicities with paucity of reports among other races. We present two cases of biopsy-confirmed MCD secondary to COVID-19 infection among adult Filipino patients. METHODS: Case Report RESULTS: Case 1 A 40-year-old Filipino female with a history of right total mastectomy 2 years prior for a low-grade phyllodes tumor and no other medical comorbidities was admitted due to stillbirth. She was noted to have bipedal edema with a positive COVID-19 RT-PCR swab. Further workup revealed a serum creatinine 1.04 mg/dL, urine RBC 1/HPF and a 24-h urine protein of 9.22 g with hypoalbuminemia and dyslipidemia. Serologic workup was noted to be negative. She was started on Losartan, Atorvastatin, and Furosemide. A kidney biopsy was performed which demonstrated unremarkable light microscopy and immunofluorescence and widespread podocyte-foot process effacement. These biopsy findings were interpreted to be consistent with minimal change disease. She was started on Prednisone at 1 mg/kg/day with continuation of both Losartan and Atorvastatin. Six weeks after, the patient achieved complete remission with resolution of both hypoalbuminemia and dyslipidemia. She also reports no further recurrence of edema. Case 2 A 61-year-old Filipino male with a history of type 2 diabetes mellitus, hypertension, dyslipidemia and mild COVID-19 infection 4 months prior now presented with diarrhea. A routine COVID-19 RT-PCR swab revealed a re-infection. Physical examination noted bipedal edema. Further workup demonstrated a serum creatinine 3.39 mg/dL, urine RBC 2/HPF and urine ACR 2.6 g/g. Serologic tests were negative. He was diagnosed with Nephrotic Syndrome and underwent kidney biopsy. Findings showed an unremarkable light microscopy and immunofluorescence with widespread podocyte-foot process effacement. These findings were found to be consistent with minimal change disease and acute tubular injury. He was started on Prednisone (1 mg/kg/day), Losartan, Furosemide and Atorvastatin. Eight weeks later, the patient achieved complete remission with resolution of edema. CONCLUSION: It is currently suspected that APOL1 risk variants found in reported cases of COVID-19-associated glomerulopathies are underlying toxic gain-of-function mutations that drive kidney disease.2 It is interesting to note that APOL1 renal risk variants are found exclusively in African-derived chromosomes and are rarely found among European or Asian chromosomes.3 Even though an APOL1 genotyping was not performed, our case reports provide the first examples of MCD among individuals without a high-risk genotype (APOL1) by epidemiology and enlarge the literature on MCD in COVID-19. We posit that there may be other underlying predispositions or mechanisms that may be driving glomerulopathy formation among COVID-19 patients aside from their inherent APOL 1 risk. Both of our patients were started on steroid therapy with a tapering regimen and achieved complete remission on subsequent follow-up. Existing reports suggest that most cases of COVID-19-associated MCD will often achieve resolution of AKI and proteinuria with steroid therapy, even in those with high-risk APOL1 genotype, emphasizing the need for an accurate histologic classification.4 (Figure Presented).