peri - renal sepsis in the setting of chronic renal failure requiring an emergency nephrectomy is rare . there is a single case report of overwhelming mrsa urosepsis in a patient with stag horn calculus who required an emergency nephrectomy . pyelonephritis accounts for 34 hospital admissions per 10 000 females , with normal renal function , and the incidence in patients with chronic pyelonephritis is not known . in patients with chronic kidney disease who are anuric , it is difficult to establish the diagnosis of renal or peri - renal sepsis . cross - sectional imaging may remain inconclusive early in the illness and at times take 23 weeks to become apparent . worsening abdominal pain with severe lactic acidosis and without peritonitis usually heralds a major intra - abdominal vascular event . while a similar presentation has been described in the setting of stone disease and mrsa sepsis , to our knowledge , this is an index case where severe peri - renal sepsis presented with life - threatening metabolic acidosis in the absence of any obvious predisposing case and possibly secondary to a fully sensitive s. 
 aureus infection . metastatic sepsis from infective endocarditis   is a well - recognized complication , and we postulate that despite adequate antibiotic therapy , this may have been the source of sepsis in this case . the interesting features that this case illustrates are that the absence of common conditions causing an acute abdomen , obscure renal or peri - renal sepsis should be considered as a possible source in anuric patients with chronic kidney disease , and that surgical management with a nephrectomy may prove necessary after failure of conservative management .
severe worsening lactic acidosis in an elderly patient following an episode of atrial fibrillation , who is not haemodynamically compromised , usually indicates an intra - abdominal vascular catastrophe . 
 we describe a unique case of severe peri - renal sepsis in a patient with long - standing dialysis - dependent chronic kidney disease unrelated to urolithiasis that masqueraded as an acute abdominal condition requiring emergency laparotomy and nephrectomy .