Methicillin-resistant Staphylococcus aureus-related glomerulonephritis in a child

We report the case of a 6-year-old girl with MRSA-GN. She presented multiple malformations, including tracheal stenosis necessitating tracheotomy. She was admitted to our hospital because of acute pneumonia caused by a MRSA infection and was found to have proteinuria and abnormal renal function. MRSA was detected in her sputum, and this MRSA isolate produced toxic shock syndrome toxin-1, which acts as a superantigen and stimulates Vβ2⁺ T cells. A blood test revealed that the number of circulating Vβ2⁺ T cells expressing CD45RO, a marker of activation, was increased along with a concomitant elevation in the levels of serum immunoglobulins. Both are hallmarks of MRSA-GN. The eradication of MRSA using appropriate antibiotics resulted in the disappearance of the proteinuria; in contrast, corticosteroid treatment failed. To the best of our knowledge, this is the youngest patient to be diagnosed with MRSA-GN.

In summary, there should be a high index of suspicion for MRSA-GN, even in the very young, in order to avoid the unnecessary use of immune suppressants in this context.