Xanthogranulomatous pyelonephritis presenting as palmoplantar keratoderma.

To cite: Caetano J, Fernandes das Neves M, Oliveira S, et al. BMJ Case Rep Published online: [please include Day Month Year] doi:10.1136/bcr-2014208511 DESCRIPTION A 60-year-old woman with type 1 diabetes mellitus and a history of repeated urinary tract infections due to Proteus mirabillis presented with diffuse palmoplantar hyperkeratosis of 4 months duration (figure 1) and acute retrosternal pain. An ECG showed a diffuse concave ST segmental elevation and the echocardiogram showed a mild pericardial effusion, suggestive of pericarditis. Laboratory analysis showed negative troponin, leucocytosis, elevated erythrocyte sedimentation rate (110 mm/h) and C reactive protein (10 mg/dL). A CT scan revealed a hydronephrotic, non-functioning left kidney with an inflammatory infiltrate in the perinephric fat and a bilateral coraliform calculus. A left radical nephrectomy was performed and the histological diagnosis of xantogranulomatous pyelonephritis was confirmed (figure 2A, B). Complete clinical remission of the cutaneous lesions and pericarditis was observed 1 month after surgery. Palmoplantar keratoderma is characterised by abnormal thickening of the skin on the palms and soles. It can be hereditary or acquired; when acquired it is associated with malignancy, drugs, infections and chronic systemic diseases, but it can also be idiopathic. Xanthogranulomatous pyelonephritis is an uncommon chronic destructive inflammatory disease of the renal parenchyma. Most cases occur in the setting of obstruction due to infected renal stones, mostly by Escherichia coli and P. mirabillis. To the best of our knowledge, this is the first case reported of acquired palmoplantar keratoderma associated with xanthogranulomatous pyelonephritis.