A 58-year-old male patient, known case of diabetes mellitus, presented to the outpatient department with complaints of edema in the hands, feet, and around the eyes for about one month and a decrease in the frequency of urination. The patient had no history of using herbal products, smoking, or alcohol. The abdomen was soft, and no defensive rebound was found in the physical examination. Edema was present in the pretibial, periorbital, and sacral regions. He had rales at the bases of both lungs on auscultation. There was no palpable lymphadenopathy. The patient's laboratory tests are summarized in Table 1. He was admitted to our ward with a prediagnosis of acute renal injury and nephrotic syndrome.
According to the detailed history taken after the patient was admitted to the ward, he received the 1st dose of the Pfizer-BioNTech COVID-19 vaccine about 50 days ago and began to develop edema after the vaccination. He had the 2nd dose of Pfizer-BioNTech COVID-19 vaccine a week ago. Therefore, he presented to the outpatient clinic due to the progressive increase in his complaints after 2nd dose of vaccination. The patient was hypertensive in the ward follow-ups. Ultrafiltration treatment was carried out 7 times intermittently to the patient who had an allergic course with resistant hypertension and diuretic-resistant hypervolemia. As the patient had hypoalbuminemia in the laboratory tests and diffuse edema in the whole body in the physical examination, a 24-hour urine collection was planned for the patient. Proteinuria of 15,935 milligrams/day was detected in 24-hour urine. Thus, the nephrotic syndrome was considered, and tests were performed to exclude rheumatological diseases in the etiology of nephrotic syndrome. In the examinations performed, c3 and c4 levels were normal. ANA, c-ANCA, p-ANCA, anti-Scl-70, anti-Jo-1, anti-SS-A, anti-SS-B, anti-dsDNA, and anti-GBM results were negative. In the hepatitis serology of the patient, HbsAg, anti-HAV IgM, anti-Hbc IgM, anti-HCV, and anti-HIV were negative. The COVID-PCR test, performed twice with a 48-hour interval, was negative. No drug could cause nephrotic syndrome among the drugs he used, and there was no drug that he had just started. There was bilateral pleural effusion in the chest X-ray. No erythrocyte casts were detected in the urine sediment from the patient.
On the other hand, leukocyte and hyaline casts were noticed in the patient's urine. As a result, tuberculosis PCR and AFB were planned for sterile pyuria, but these tests were negative. The patient was examined for microvascular complications to exclude nephrotic syndrome due to diabetes mellitus and retinopathy was not detected in the examination. Peripheral smear, immunofixation electrophoresis, and protein electrophoresis were implemented to exclude multiple myeloma and other plasma cell dyscrasias because of the high sedimentation level, anemia, and nephrotic level proteinuria (while spot urine protein was negative by the dipstick method, 16 g/day proteinuria was found in 24-hour urine). No atypical cell and roll formation was detected in the peripheral smear. IgM kappa monoclonal gammopathy was detected in immunofixation electrophoresis. Abdominal ultrasound demonstrated no pathology, and superficial ultrasound did not detect lymphadenopathy. Bone marrow biopsy was performed, and the biopsy reported a hypercellular bone marrow and aspiration smear with increased myeloid and erythroid series. Flow cytometry sent from the bone marrow sample was not compatible with myeloma. As a result of the examinations, multiple myeloma and other plasma cell dyscrasias were excluded from the case. Considering the current clinical situation of the patient and the fact that monoclonal gammopathy detected in the bone marrow may also be observed in renal lymphoma, positron emission tomography (PET-CT) was carried out on the patient. No malignancy or additional pathology was suggested after the PET-CT findings. Cryoglobulins were tested to exclude the causes of secondary nephrotic syndrome, and it was negative. Rectal biopsy was performed to exclude amyloidosis in the patient with diffuse edema at the nephrotic level and biopsy was negative for amyloidosis. Lower extremity Doppler ultrasonography was performed because of edema in both lower extremities, and deep vein thrombosis was not found in the ultrasonography. A renal biopsy was planned for the patient to determine the cause of the newly developed nephrotic syndrome. Renal biopsy demonstrated that findings were consistent with minimal change disease (Figures 1-3).
We started 80 mg of methylprednisolone intravenously. Afterward, urea and creatinine values decreased, and urine output returned to normal. The dose was gradually reduced, and the patient continued methylprednisolone treatment. The clinical picture of hypervolemia improved on the 10th day after the treatment. The proteinuria decreased to 67 milligrams in the 24-hour urine collected as control samples. The patient is followed up with 16 mg methylprednisolone treatment. The history taken from the patient showed that his symptoms developed after the Pfizer-BioNTech COVID-19 vaccine. Hence, secondary causes of nephrotic syndrome were excluded with the examinations. The case was evaluated as a minimal change disease developed after the Pfizer-BioNTech COVID-19 vaccine, since the complaints in the history and the current clinic developed after the vaccine.