Abscessing Infection by Streptococcus mitis Mimicking Metastatic Lesions in a 5-Year-Old Girl With Nephroblastoma: A Case Report.

Streptococcus mitis is a common pathogen causing infections in oncological patients. However, cases of abscesses caused by Streptococcus mitis in oncological patients have not been reported so far. We report on 5-year-old child with nephroblastoma and pulmonary and hepatic metastases at diagnosis who went into complete remission undergoing chemotherapy and nephrectomy, and who developed new round lesions in liver and lungs under continuous chemotherapy suggestive of new metastases.