Tubulointerstitial nephritis and uveitis syndrome and SARS-CoV-2 infection in an adolescent: just a coincidence in time?

BACKGROUND: Despite recent well-established kidney tropism of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), usually presenting as acute kidney injury (AKI), there are few published cases with SARS-CoV-2-related tubulointerstitial nephritis (TIN). We report an adolescent with TIN and delayed association with uveitis (TINU syndrome), where SARS-CoV-2 spike protein was identified in kidney biopsy. CASE-DIAGNOSIS/TREATMENT: A 12-year-old girl was assessed for a mild elevation of serum creatinine detected during the evaluation of systemic manifestations including asthenia, anorexia, abdominal pain, vomiting, and weight loss. Data of incomplete proximal tubular dysfunction (hypophosphatemia and hypouricemia with inappropriate urinary losses, low molecular weight proteinuria, and glucosuria) were also associated. Symptoms had initiated after a febrile respiratory infection with no known infectious cause. After 8 weeks, the patient tested positive in PCR for SARS-CoV-2 (Omicron variant). A subsequent percutaneous kidney biopsy revealed TIN and immunofluorescence staining with confocal microscopy detected the presence of SARS-CoV-2 protein S within the kidney interstitium. Steroid therapy was started with gradual tapering. Ten months after onset of clinical manifestations, as serum creatinine remained slightly elevated and kidney ultrasound showed mild bilateral parenchymal cortical thinning, a second percutaneous kidney biopsy was performed, without demonstrating acute inflammation or chronic changes, but SARS-CoV-2 protein S within the kidney tissue was again detected. At that moment, simultaneous routine ophthalmological examination revealed an asymptomatic bilateral anterior uveitis. CONCLUSIONS: We present a patient who was found to have SARS-CoV-2 in kidney tissue several weeks following onset of TINU syndrome. Although simultaneous infection by SARS-CoV-2 could not be demonstrated at onset of symptoms, since no other etiological cause was identified, we hypothesize that SARS-CoV-2 might have been involved in triggering the patient's illness.

[Experience with Denosumab in central giant-cell granuloma]. / Experiencia con Denosumab en granuloma central de células gigantes.

INTRODUCTION: Central Giant Cell Granuloma is an infrequent bone lesion located mainly in the maxillary bone. The main treatment is surgery with wide margins, so it sometimes causes great morbidity and esthetic al terations. Denosumab, a RANK-ligand inhibitor monoclonal antibody, has been presented as a valid therapeutic alternative in the treatment of these lesions. OBJECTIVE: to describe the clinical and radio logical response after treatment with Denosumab in a patient with unresected giant cell granuloma. CLINICAL CASE: 12-year-old boy who consulted due to a 24-hour maxillary swelling, without other associated symptoms. Examination revealed a tumor in the upper left maxilla with bulging of the ip- silateral gingiva. A CT scan was performed which showed a large expansive intraosseous lesion in the maxillary alveolar ridge. The biopsy of the lesion was compatible with Central Giant Cell Granuloma. Due to the size and location of the lesion, initial treatment with Denosumab, a human monoclonal antibody with action on RANK-ligand, was indicated. After 10 months of treatment, the patient showed a favorable clinical and radiological response, with a size decrease of the lesion and metabolic activity. As an adverse effect, the boy presented mild hypocalcemia, resolved after supplementation with calcium. CONCLUSION: the use of Denosumab as the first line of treatment in Giant Cell Granu loma may be an adequate therapeutic option in adolescents with lesions that are difficult to resect.