Massive kidney infarct, due to total occlusion of the main artery, is not a frequent process in clinical urology. The most frequent causes are endocarditis, arteritis, atheromatosis and traumatisms. The complete blockage of the renal artery means that the tissue irrigated by the same is bloodless and prone to necrosis and it must be taken into account that although the renal parenchyma cannot withstand for more than 1 to 2 hours the lack of a blood supply, the obstructions or ischemias of shorter duration cause tissue disorders of greater or lesser importance, affecting more quickly and more intensely the cells of the tubules, than those of the glomerules and later the connecting tissue. Clinically, kidney infarcts may sometimes go unobserved and on many other occasions their symptoms are by no means typical although the most characteristic feature is a more intense, sharp, acute pain with macroscopic hematuria, proteinuria and cylindruria and, in the radiological exploration, kidney "silence" but with the excretory duct intact shown by means of retrograde uretero-pyelography. The kidney angiography will reveal the existence of the arterial obstruction, with the resulting avascular image. Extrapremature surgical treatment would be ideal in the cases of massive infarct but this would also require an extrapremature diagnosis, which would enable the embolectomy (where necessary to be carried out, thereby saving the kidney. However, under normal working conditions, taking into account the period of time which inevitably elapses between the patient feeling pain in the kidney and his reaching the Emergency Department and the necessary examinations being carried out which enable the correct diagnosis to be made, the number of hours which have passed make attempts at conservative surgery completely useless. The authors present the case of a 37-year old patient who, 15 days after presenting a picture of right kidney colic, went to the Emergency Department in our Centre where the doctor on duty merely performed a symptomatic treatment and the patient was not admitted to our Department until several days later. In the different radiourographic examinations carried out, right kidney mutism was observed, as well as the permeability of the excretory duct. The aortography revealed the total occlusion of the right renal artery. As more than 20 days had elapsed since the patient first presented the colic pain and before we examined him, there was no other therapeutic solution but the performing of a nephrectomy. The examination of the organ removed confirmed the diagnosis but the origin of the arterial obstruction could not be clarified for sure.