@article {Ramasamy396, author = {Vijaya BP Ramasamy and Rhiannon Trefor and Kaushik Rajamani and Divya Santosh and David Griffiths and Kieron Donovan}, title = {Lesson of the month 2: IgG4-related renal mass with spontaneous resolution}, volume = {15}, number = {4}, pages = {396--398}, year = {2015}, doi = {10.7861/clinmedicine.15-4-396}, publisher = {Royal College of Physicians}, abstract = {Immunoglobulin G4-related disease (IgG4-RD) is a systemic inflammatory condition that may involve any organ in the body, including the kidneys. However, renal parenchymal lesions are not seen frequently and the treatment strategy remains unclear. We describe a case of IgG4-related renal mass, which resolved spontaneously. The patient presented with right loin pain, constitutional symptoms and raised inflammatory markers. Magnetic resonance imaging (MRI) showed a large infiltrative mass centered on the right renal hilum and biopsy demonstrated histological changes in keeping with IgG4-RD. A careful {\textquoteleft}watch-and-wait{\textquoteright} approach was taken and at six months following initial presentation, the patient{\textquoteright}s symptoms had fully resolved and inflammatory markers had normalised. Repeat MRI showed almost complete resolution of the mass. We propose that a careful {\textquoteleft}watch-and-wait{\textquoteright} approach could be considered as an alternative to immune suppression for IgG4-related renal masses, especially if they are not causing symptoms or organ compromise.}, issn = {1470-2118}, URL = {https://www.rcpjournals.org/content/15/4/396}, eprint = {https://www.rcpjournals.org/content/15/4/396.full.pdf}, journal = {Clinical Medicine} }